drivers/nfc/trf7970a.c

   1 /*
   2  * TI TRF7970a RFID/NFC Transceiver Driver
   3  *
   4  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
   5  *
   6  * Author: Erick Macias <emacias@ti.com>
   7  * Author: Felipe Balbi <balbi@ti.com>
   8  * Author: Mark A. Greer <mgreer@animalcreek.com>
   9  *
  10  * This program is free software: you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2  of
  12  * the License as published by the Free Software Foundation.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/device.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/pm_runtime.h>
  20 #include <linux/nfc.h>
  21 #include <linux/skbuff.h>
  22 #include <linux/delay.h>
  23 #include <linux/gpio.h>
  24 #include <linux/of.h>
  25 #include <linux/of_gpio.h>
  26 #include <linux/spi/spi.h>
  27 #include <linux/regulator/consumer.h>
  28
  29 #include <net/nfc/nfc.h>
  30 #include <net/nfc/digital.h>
  31
  32 /* There are 3 ways the host can communicate with the trf7970a:
  33  * parallel mode, SPI with Slave Select (SS) mode, and SPI without
  34  * SS mode.  The driver only supports the two SPI modes.
  35  *
  36  * The trf7970a is very timing sensitive and the VIN, EN2, and EN
  37  * pins must asserted in that order and with specific delays in between.
  38  * The delays used in the driver were provided by TI and have been
  39  * confirmed to work with this driver.  There is a bug with the current
  40  * version of the trf7970a that requires that EN2 remain low no matter
  41  * what.  If it goes high, it will generate an RF field even when in
  42  * passive target mode.  TI has indicated that the chip will work okay
  43  * when EN2 is left low.  The 'en2-rf-quirk' device tree property
  44  * indicates that trf7970a currently being used has the erratum and
  45  * that EN2 must be kept low.
  46  *
  47  * Timeouts are implemented using the delayed workqueue kernel facility.
  48  * Timeouts are required so things don't hang when there is no response
  49  * from the trf7970a (or tag).  Using this mechanism creates a race with
  50  * interrupts, however.  That is, an interrupt and a timeout could occur
  51  * closely enough together that one is blocked by the mutex while the other
  52  * executes.  When the timeout handler executes first and blocks the
  53  * interrupt handler, it will eventually set the state to IDLE so the
  54  * interrupt handler will check the state and exit with no harm done.
  55  * When the interrupt handler executes first and blocks the timeout handler,
  56  * the cancel_delayed_work() call will know that it didn't cancel the
  57  * work item (i.e., timeout) and will return zero.  That return code is
  58  * used by the timer handler to indicate that it should ignore the timeout
  59  * once its unblocked.
  60  *
  61  * Aborting an active command isn't as simple as it seems because the only
  62  * way to abort a command that's already been sent to the tag is so turn
  63  * off power to the tag.  If we do that, though, we'd have to go through
  64  * the entire anticollision procedure again but the digital layer doesn't
  65  * support that.  So, if an abort is received before trf7970a_send_cmd()
  66  * has sent the command to the tag, it simply returns -ECANCELED.  If the
  67  * command has already been sent to the tag, then the driver continues
  68  * normally and recieves the response data (or error) but just before
  69  * sending the data upstream, it frees the rx_skb and sends -ECANCELED
  70  * upstream instead.  If the command failed, that error will be sent
  71  * upstream.
  72  *
  73  * When recieving data from a tag and the interrupt status register has
  74  * only the SRX bit set, it means that all of the data has been received
  75  * (once what's in the fifo has been read).  However, depending on timing
  76  * an interrupt status with only the SRX bit set may not be recived.  In
  77  * those cases, the timeout mechanism is used to wait 20 ms in case more
  78  * data arrives.  After 20 ms, it is assumed that all of the data has been
  79  * received and the accumulated rx data is sent upstream.  The
  80  * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
  81  * (i.e., it indicates that some data has been received but we're not sure
  82  * if there is more coming so a timeout in this state means all data has
  83  * been received and there isn't an error).  The delay is 20 ms since delays
  84  * of ~16 ms have been observed during testing.
  85  *
  86  * When transmitting a frame larger than the FIFO size (127 bytes), the
  87  * driver will wait 20 ms for the FIFO to drain past the low-watermark
  88  * and generate an interrupt.  The low-watermark set to 32 bytes so the
  89  * interrupt should fire after 127 - 32 = 95 bytes have been sent.  At
  90  * the lowest possible bit rate (6.62 kbps for 15693), it will take up
  91  * to ~14.35 ms so 20 ms is used for the timeout.
  92  *
  93  * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
  94  * Having only 4 bits in the FIFO won't normally generate an interrupt so
  95  * driver enables the '4_bit_RX' bit of the Special Functions register 1
  96  * to cause an interrupt in that case.  Leaving that bit for a read command
  97  * messes up the data returned so it is only enabled when the framing is
  98  * 'NFC_DIGITAL_FRAMING_NFCA_T2T' and the command is not a read command.
  99  * Unfortunately, that means that the driver has to peek into tx frames
 100  * when the framing is 'NFC_DIGITAL_FRAMING_NFCA_T2T'.  This is done by
 101  * the trf7970a_per_cmd_config() routine.
 102  *
 103  * ISO/IEC 15693 frames specify whether to use single or double sub-carrier
 104  * frequencies and whether to use low or high data rates in the flags byte
 105  * of the frame.  This means that the driver has to peek at all 15693 frames
 106  * to determine what speed to set the communication to.  In addition, write
 107  * and lock commands use the OPTION flag to indicate that an EOF must be
 108  * sent to the tag before it will send its response.  So the driver has to
 109  * examine all frames for that reason too.
 110  *
 111  * It is unclear how long to wait before sending the EOF.  According to the
 112  * Note under Table 1-1 in section 1.6 of
 113  * http://www.ti.com/lit/ug/scbu011/scbu011.pdf, that wait should be at least
 114  * 10 ms for TI Tag-it HF-I tags; however testing has shown that is not long
 115  * enough so 20 ms is used.  So the timer is set to 40 ms - 20 ms to drain
 116  * up to 127 bytes in the FIFO at the lowest bit rate plus another 20 ms to
 117  * ensure the wait is long enough before sending the EOF.  This seems to work
 118  * reliably.
 119  */
 120
 121 #define TRF7970A_SUPPORTED_PROTOCOLS \
 122                 (NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |      \
 123                  NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
 124                  NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
 125
 126 #define TRF7970A_AUTOSUSPEND_DELAY              30000 /* 30 seconds */
 127
 128 #define TRF7970A_RX_SKB_ALLOC_SIZE              256
 129
 130 #define TRF7970A_FIFO_SIZE                      127
 131
 132 /* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
 133 #define TRF7970A_TX_MAX                         (4096 - 1)
 134
 135 #define TRF7970A_WAIT_FOR_TX_IRQ                20
 136 #define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT       20
 137 #define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT    20
 138 #define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF     40
 139
 140 /* Guard times for various RF technologies (in us) */
 141 #define TRF7970A_GUARD_TIME_NFCA                5000
 142 #define TRF7970A_GUARD_TIME_NFCB                5000
 143 #define TRF7970A_GUARD_TIME_NFCF                20000
 144 #define TRF7970A_GUARD_TIME_15693               1000
 145
 146 /* Quirks */
 147 /* Erratum: When reading IRQ Status register on trf7970a, we must issue a
 148  * read continuous command for IRQ Status and Collision Position registers.
 149  */
 150 #define TRF7970A_QUIRK_IRQ_STATUS_READ          BIT(0)
 151 #define TRF7970A_QUIRK_EN2_MUST_STAY_LOW        BIT(1)
 152
 153 /* Direct commands */
 154 #define TRF7970A_CMD_IDLE                       0x00
 155 #define TRF7970A_CMD_SOFT_INIT                  0x03
 156 #define TRF7970A_CMD_RF_COLLISION               0x04
 157 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_N    0x05
 158 #define TRF7970A_CMD_RF_COLLISION_RESPONSE_0    0x06
 159 #define TRF7970A_CMD_FIFO_RESET                 0x0f
 160 #define TRF7970A_CMD_TRANSMIT_NO_CRC            0x10
 161 #define TRF7970A_CMD_TRANSMIT                   0x11
 162 #define TRF7970A_CMD_DELAY_TRANSMIT_NO_CRC      0x12
 163 #define TRF7970A_CMD_DELAY_TRANSMIT             0x13
 164 #define TRF7970A_CMD_EOF                        0x14
 165 #define TRF7970A_CMD_CLOSE_SLOT                 0x15
 166 #define TRF7970A_CMD_BLOCK_RX                   0x16
 167 #define TRF7970A_CMD_ENABLE_RX                  0x17
 168 #define TRF7970A_CMD_TEST_INT_RF                0x18
 169 #define TRF7970A_CMD_TEST_EXT_RF                0x19
 170 #define TRF7970A_CMD_RX_GAIN_ADJUST             0x1a
 171
 172 /* Bits determining whether its a direct command or register R/W,
 173  * whether to use a continuous SPI transaction or not, and the actual
 174  * direct cmd opcode or regster address.
 175  */
 176 #define TRF7970A_CMD_BIT_CTRL                   BIT(7)
 177 #define TRF7970A_CMD_BIT_RW                     BIT(6)
 178 #define TRF7970A_CMD_BIT_CONTINUOUS             BIT(5)
 179 #define TRF7970A_CMD_BIT_OPCODE(opcode)         ((opcode) & 0x1f)
 180
 181 /* Registers addresses */
 182 #define TRF7970A_CHIP_STATUS_CTRL               0x00
 183 #define TRF7970A_ISO_CTRL                       0x01
 184 #define TRF7970A_ISO14443B_TX_OPTIONS           0x02
 185 #define TRF7970A_ISO14443A_HIGH_BITRATE_OPTIONS 0x03
 186 #define TRF7970A_TX_TIMER_SETTING_H_BYTE        0x04
 187 #define TRF7970A_TX_TIMER_SETTING_L_BYTE        0x05
 188 #define TRF7970A_TX_PULSE_LENGTH_CTRL           0x06
 189 #define TRF7970A_RX_NO_RESPONSE_WAIT            0x07
 190 #define TRF7970A_RX_WAIT_TIME                   0x08
 191 #define TRF7970A_MODULATOR_SYS_CLK_CTRL         0x09
 192 #define TRF7970A_RX_SPECIAL_SETTINGS            0x0a
 193 #define TRF7970A_REG_IO_CTRL                    0x0b
 194 #define TRF7970A_IRQ_STATUS                     0x0c
 195 #define TRF7970A_COLLISION_IRQ_MASK             0x0d
 196 #define TRF7970A_COLLISION_POSITION             0x0e
 197 #define TRF7970A_RSSI_OSC_STATUS                0x0f
 198 #define TRF7970A_SPECIAL_FCN_REG1               0x10
 199 #define TRF7970A_SPECIAL_FCN_REG2               0x11
 200 #define TRF7970A_RAM1                           0x12
 201 #define TRF7970A_RAM2                           0x13
 202 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS      0x14
 203 #define TRF7970A_NFC_LOW_FIELD_LEVEL            0x16
 204 #define TRF7970A_NFCID1                         0x17
 205 #define TRF7970A_NFC_TARGET_LEVEL               0x18
 206 #define TRF79070A_NFC_TARGET_PROTOCOL           0x19
 207 #define TRF7970A_TEST_REGISTER1                 0x1a
 208 #define TRF7970A_TEST_REGISTER2                 0x1b
 209 #define TRF7970A_FIFO_STATUS                    0x1c
 210 #define TRF7970A_TX_LENGTH_BYTE1                0x1d
 211 #define TRF7970A_TX_LENGTH_BYTE2                0x1e
 212 #define TRF7970A_FIFO_IO_REGISTER               0x1f
 213
 214 /* Chip Status Control Register Bits */
 215 #define TRF7970A_CHIP_STATUS_VRS5_3             BIT(0)
 216 #define TRF7970A_CHIP_STATUS_REC_ON             BIT(1)
 217 #define TRF7970A_CHIP_STATUS_AGC_ON             BIT(2)
 218 #define TRF7970A_CHIP_STATUS_PM_ON              BIT(3)
 219 #define TRF7970A_CHIP_STATUS_RF_PWR             BIT(4)
 220 #define TRF7970A_CHIP_STATUS_RF_ON              BIT(5)
 221 #define TRF7970A_CHIP_STATUS_DIRECT             BIT(6)
 222 #define TRF7970A_CHIP_STATUS_STBY               BIT(7)
 223
 224 /* ISO Control Register Bits */
 225 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_662    0x00
 226 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_662  0x01
 227 #define TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648   0x02
 228 #define TRF7970A_ISO_CTRL_15693_SGL_1OF256_2648 0x03
 229 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a   0x04
 230 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_667  0x05
 231 #define TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669   0x06
 232 #define TRF7970A_ISO_CTRL_15693_DBL_1OF256_2669 0x07
 233 #define TRF7970A_ISO_CTRL_14443A_106            0x08
 234 #define TRF7970A_ISO_CTRL_14443A_212            0x09
 235 #define TRF7970A_ISO_CTRL_14443A_424            0x0a
 236 #define TRF7970A_ISO_CTRL_14443A_848            0x0b
 237 #define TRF7970A_ISO_CTRL_14443B_106            0x0c
 238 #define TRF7970A_ISO_CTRL_14443B_212            0x0d
 239 #define TRF7970A_ISO_CTRL_14443B_424            0x0e
 240 #define TRF7970A_ISO_CTRL_14443B_848            0x0f
 241 #define TRF7970A_ISO_CTRL_FELICA_212            0x1a
 242 #define TRF7970A_ISO_CTRL_FELICA_424            0x1b
 243 #define TRF7970A_ISO_CTRL_NFC_NFCA_106          0x01
 244 #define TRF7970A_ISO_CTRL_NFC_NFCF_212          0x02
 245 #define TRF7970A_ISO_CTRL_NFC_NFCF_424          0x03
 246 #define TRF7970A_ISO_CTRL_NFC_CE_14443A         0x00
 247 #define TRF7970A_ISO_CTRL_NFC_CE_14443B         0x01
 248 #define TRF7970A_ISO_CTRL_NFC_CE                BIT(2)
 249 #define TRF7970A_ISO_CTRL_NFC_ACTIVE            BIT(3)
 250 #define TRF7970A_ISO_CTRL_NFC_INITIATOR         BIT(4)
 251 #define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE       BIT(5)
 252 #define TRF7970A_ISO_CTRL_RFID                  BIT(5)
 253 #define TRF7970A_ISO_CTRL_DIR_MODE              BIT(6)
 254 #define TRF7970A_ISO_CTRL_RX_CRC_N              BIT(7)  /* true == No CRC */
 255
 256 #define TRF7970A_ISO_CTRL_RFID_SPEED_MASK       0x1f
 257
 258 /* Modulator and SYS_CLK Control Register Bits */
 259 #define TRF7970A_MODULATOR_DEPTH(n)             ((n) & 0x7)
 260 #define TRF7970A_MODULATOR_DEPTH_ASK10          (TRF7970A_MODULATOR_DEPTH(0))
 261 #define TRF7970A_MODULATOR_DEPTH_OOK            (TRF7970A_MODULATOR_DEPTH(1))
 262 #define TRF7970A_MODULATOR_DEPTH_ASK7           (TRF7970A_MODULATOR_DEPTH(2))
 263 #define TRF7970A_MODULATOR_DEPTH_ASK8_5         (TRF7970A_MODULATOR_DEPTH(3))
 264 #define TRF7970A_MODULATOR_DEPTH_ASK13          (TRF7970A_MODULATOR_DEPTH(4))
 265 #define TRF7970A_MODULATOR_DEPTH_ASK16          (TRF7970A_MODULATOR_DEPTH(5))
 266 #define TRF7970A_MODULATOR_DEPTH_ASK22          (TRF7970A_MODULATOR_DEPTH(6))
 267 #define TRF7970A_MODULATOR_DEPTH_ASK30          (TRF7970A_MODULATOR_DEPTH(7))
 268 #define TRF7970A_MODULATOR_EN_ANA               BIT(3)
 269 #define TRF7970A_MODULATOR_CLK(n)               (((n) & 0x3) << 4)
 270 #define TRF7970A_MODULATOR_CLK_DISABLED         (TRF7970A_MODULATOR_CLK(0))
 271 #define TRF7970A_MODULATOR_CLK_3_6              (TRF7970A_MODULATOR_CLK(1))
 272 #define TRF7970A_MODULATOR_CLK_6_13             (TRF7970A_MODULATOR_CLK(2))
 273 #define TRF7970A_MODULATOR_CLK_13_27            (TRF7970A_MODULATOR_CLK(3))
 274 #define TRF7970A_MODULATOR_EN_OOK               BIT(6)
 275 #define TRF7970A_MODULATOR_27MHZ                BIT(7)
 276
 277 #define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM     BIT(0)
 278 #define TRF7970A_RX_SPECIAL_SETTINGS_AGCR       BIT(1)
 279 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB     (0x0 << 2)
 280 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB     (0x1 << 2)
 281 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB    (0x2 << 2)
 282 #define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB    (0x3 << 2)
 283 #define TRF7970A_RX_SPECIAL_SETTINGS_HBT        BIT(4)
 284 #define TRF7970A_RX_SPECIAL_SETTINGS_M848       BIT(5)
 285 #define TRF7970A_RX_SPECIAL_SETTINGS_C424       BIT(6)
 286 #define TRF7970A_RX_SPECIAL_SETTINGS_C212       BIT(7)
 287
 288 #define TRF7970A_REG_IO_CTRL_VRS(v)             ((v) & 0x07)
 289 #define TRF7970A_REG_IO_CTRL_IO_LOW             BIT(5)
 290 #define TRF7970A_REG_IO_CTRL_EN_EXT_PA          BIT(6)
 291 #define TRF7970A_REG_IO_CTRL_AUTO_REG           BIT(7)
 292
 293 /* IRQ Status Register Bits */
 294 #define TRF7970A_IRQ_STATUS_NORESP              BIT(0) /* ISO15693 only */
 295 #define TRF7970A_IRQ_STATUS_NFC_COL_ERROR       BIT(0)
 296 #define TRF7970A_IRQ_STATUS_COL                 BIT(1)
 297 #define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR   BIT(2)
 298 #define TRF7970A_IRQ_STATUS_NFC_RF              BIT(2)
 299 #define TRF7970A_IRQ_STATUS_PARITY_ERROR        BIT(3)
 300 #define TRF7970A_IRQ_STATUS_NFC_SDD             BIT(3)
 301 #define TRF7970A_IRQ_STATUS_CRC_ERROR           BIT(4)
 302 #define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR     BIT(4)
 303 #define TRF7970A_IRQ_STATUS_FIFO                BIT(5)
 304 #define TRF7970A_IRQ_STATUS_SRX                 BIT(6)
 305 #define TRF7970A_IRQ_STATUS_TX                  BIT(7)
 306
 307 #define TRF7970A_IRQ_STATUS_ERROR                               \
 308                 (TRF7970A_IRQ_STATUS_COL |                      \
 309                  TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR |        \
 310                  TRF7970A_IRQ_STATUS_PARITY_ERROR |             \
 311                  TRF7970A_IRQ_STATUS_CRC_ERROR)
 312
 313 #define TRF7970A_RSSI_OSC_STATUS_RSSI_MASK      (BIT(2) | BIT(1) | BIT(0))
 314 #define TRF7970A_RSSI_OSC_STATUS_RSSI_X_MASK    (BIT(5) | BIT(4) | BIT(3))
 315 #define TRF7970A_RSSI_OSC_STATUS_RSSI_OSC_OK    BIT(6)
 316
 317 #define TRF7970A_SPECIAL_FCN_REG1_COL_7_6               BIT(0)
 318 #define TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL           BIT(1)
 319 #define TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX              BIT(2)
 320 #define TRF7970A_SPECIAL_FCN_REG1_SP_DIR_MODE           BIT(3)
 321 #define TRF7970A_SPECIAL_FCN_REG1_NEXT_SLOT_37US        BIT(4)
 322 #define TRF7970A_SPECIAL_FCN_REG1_PAR43                 BIT(5)
 323
 324 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_124      (0x0 << 2)
 325 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_120      (0x1 << 2)
 326 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_112      (0x2 << 2)
 327 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96       (0x3 << 2)
 328 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_4        0x0
 329 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_8        0x1
 330 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16       0x2
 331 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32       0x3
 332
 333 #define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)   ((v) & 0x07)
 334 #define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS   BIT(7)
 335
 336 #define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)      ((v) & 0x07)
 337 #define TRF7970A_NFC_TARGET_LEVEL_HI_RF         BIT(3)
 338 #define TRF7970A_NFC_TARGET_LEVEL_SDD_EN        BIT(3)
 339 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES   (0x0 << 6)
 340 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES   (0x1 << 6)
 341 #define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES  (0x2 << 6)
 342
 343 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106         BIT(0)
 344 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212         BIT(1)
 345 #define TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424         (BIT(0) | BIT(1))
 346 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B        BIT(2)
 347 #define TRF79070A_NFC_TARGET_PROTOCOL_PAS_106           BIT(3)
 348 #define TRF79070A_NFC_TARGET_PROTOCOL_FELICA            BIT(4)
 349 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_L              BIT(6)
 350 #define TRF79070A_NFC_TARGET_PROTOCOL_RF_H              BIT(7)
 351
 352 #define TRF79070A_NFC_TARGET_PROTOCOL_106A              \
 353          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 354           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 355           TRF79070A_NFC_TARGET_PROTOCOL_PAS_106 |       \
 356           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 357
 358 #define TRF79070A_NFC_TARGET_PROTOCOL_106B              \
 359          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 360           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 361           TRF79070A_NFC_TARGET_PROTOCOL_PAS_14443B |    \
 362           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_106)
 363
 364 #define TRF79070A_NFC_TARGET_PROTOCOL_212F              \
 365          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 366           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 367           TRF79070A_NFC_TARGET_PROTOCOL_FELICA |        \
 368           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_212)
 369
 370 #define TRF79070A_NFC_TARGET_PROTOCOL_424F              \
 371          (TRF79070A_NFC_TARGET_PROTOCOL_RF_H |          \
 372           TRF79070A_NFC_TARGET_PROTOCOL_RF_L |          \
 373           TRF79070A_NFC_TARGET_PROTOCOL_FELICA |        \
 374           TRF79070A_NFC_TARGET_PROTOCOL_NFCBR_424)
 375
 376 #define TRF7970A_FIFO_STATUS_OVERFLOW           BIT(7)
 377
 378 /* NFC (ISO/IEC 14443A) Type 2 Tag commands */
 379 #define NFC_T2T_CMD_READ                        0x30
 380
 381 /* ISO 15693 commands codes */
 382 #define ISO15693_CMD_INVENTORY                  0x01
 383 #define ISO15693_CMD_READ_SINGLE_BLOCK          0x20
 384 #define ISO15693_CMD_WRITE_SINGLE_BLOCK         0x21
 385 #define ISO15693_CMD_LOCK_BLOCK                 0x22
 386 #define ISO15693_CMD_READ_MULTIPLE_BLOCK        0x23
 387 #define ISO15693_CMD_WRITE_MULTIPLE_BLOCK       0x24
 388 #define ISO15693_CMD_SELECT                     0x25
 389 #define ISO15693_CMD_RESET_TO_READY             0x26
 390 #define ISO15693_CMD_WRITE_AFI                  0x27
 391 #define ISO15693_CMD_LOCK_AFI                   0x28
 392 #define ISO15693_CMD_WRITE_DSFID                0x29
 393 #define ISO15693_CMD_LOCK_DSFID                 0x2a
 394 #define ISO15693_CMD_GET_SYSTEM_INFO            0x2b
 395 #define ISO15693_CMD_GET_MULTIPLE_BLOCK_SECURITY_STATUS 0x2c
 396
 397 /* ISO 15693 request and response flags */
 398 #define ISO15693_REQ_FLAG_SUB_CARRIER           BIT(0)
 399 #define ISO15693_REQ_FLAG_DATA_RATE             BIT(1)
 400 #define ISO15693_REQ_FLAG_INVENTORY             BIT(2)
 401 #define ISO15693_REQ_FLAG_PROTOCOL_EXT          BIT(3)
 402 #define ISO15693_REQ_FLAG_SELECT                BIT(4)
 403 #define ISO15693_REQ_FLAG_AFI                   BIT(4)
 404 #define ISO15693_REQ_FLAG_ADDRESS               BIT(5)
 405 #define ISO15693_REQ_FLAG_NB_SLOTS              BIT(5)
 406 #define ISO15693_REQ_FLAG_OPTION                BIT(6)
 407
 408 #define ISO15693_REQ_FLAG_SPEED_MASK \
 409                 (ISO15693_REQ_FLAG_SUB_CARRIER | ISO15693_REQ_FLAG_DATA_RATE)
 410
 411 enum trf7970a_state {
 412         TRF7970A_ST_PWR_OFF,
 413         TRF7970A_ST_RF_OFF,
 414         TRF7970A_ST_IDLE,
 415         TRF7970A_ST_IDLE_RX_BLOCKED,
 416         TRF7970A_ST_WAIT_FOR_TX_FIFO,
 417         TRF7970A_ST_WAIT_FOR_RX_DATA,
 418         TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
 419         TRF7970A_ST_WAIT_TO_ISSUE_EOF,
 420         TRF7970A_ST_LISTENING,
 421         TRF7970A_ST_LISTENING_MD,
 422         TRF7970A_ST_MAX
 423 };
 424
 425 struct trf7970a {
 426         enum trf7970a_state             state;
 427         struct device                   *dev;
 428         struct spi_device               *spi;
 429         struct regulator                *regulator;
 430         struct nfc_digital_dev          *ddev;
 431         u32                             quirks;
 432         bool                            is_initiator;
 433         bool                            aborting;
 434         struct sk_buff                  *tx_skb;
 435         struct sk_buff                  *rx_skb;
 436         nfc_digital_cmd_complete_t      cb;
 437         void                            *cb_arg;
 438         u8                              chip_status_ctrl;
 439         u8                              iso_ctrl;
 440         u8                              iso_ctrl_tech;
 441         u8                              modulator_sys_clk_ctrl;
 442         u8                              special_fcn_reg1;
 443         unsigned int                    guard_time;
 444         int                             technology;
 445         int                             framing;
 446         u8                              md_rf_tech;
 447         u8                              tx_cmd;
 448         bool                            issue_eof;
 449         int                             en2_gpio;
 450         int                             en_gpio;
 451         struct mutex                    lock;
 452         unsigned int                    timeout;
 453         bool                            ignore_timeout;
 454         struct delayed_work             timeout_work;
 455 };
 456
 457
 458 static int trf7970a_cmd(struct trf7970a *trf, u8 opcode)
 459 {
 460         u8 cmd = TRF7970A_CMD_BIT_CTRL | TRF7970A_CMD_BIT_OPCODE(opcode);
 461         int ret;
 462
 463         dev_dbg(trf->dev, "cmd: 0x%x\n", cmd);
 464
 465         ret = spi_write(trf->spi, &cmd, 1);
 466         if (ret)
 467                 dev_err(trf->dev, "%s - cmd: 0x%x, ret: %d\n", __func__, cmd,
 468                                 ret);
 469         return ret;
 470 }
 471
 472 static int trf7970a_read(struct trf7970a *trf, u8 reg, u8 *val)
 473 {
 474         u8 addr = TRF7970A_CMD_BIT_RW | reg;
 475         int ret;
 476
 477         ret = spi_write_then_read(trf->spi, &addr, 1, val, 1);
 478         if (ret)
 479                 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 480                                 ret);
 481
 482         dev_dbg(trf->dev, "read(0x%x): 0x%x\n", addr, *val);
 483
 484         return ret;
 485 }
 486
 487 static int trf7970a_read_cont(struct trf7970a *trf, u8 reg, u8 *buf, size_t len)
 488 {
 489         u8 addr = reg | TRF7970A_CMD_BIT_RW | TRF7970A_CMD_BIT_CONTINUOUS;
 490         struct spi_transfer t[2];
 491         struct spi_message m;
 492         int ret;
 493
 494         dev_dbg(trf->dev, "read_cont(0x%x, %zd)\n", addr, len);
 495
 496         spi_message_init(&m);
 497
 498         memset(&t, 0, sizeof(t));
 499
 500         t[0].tx_buf = &addr;
 501         t[0].len = sizeof(addr);
 502         spi_message_add_tail(&t[0], &m);
 503
 504         t[1].rx_buf = buf;
 505         t[1].len = len;
 506         spi_message_add_tail(&t[1], &m);
 507
 508         ret = spi_sync(trf->spi, &m);
 509         if (ret)
 510                 dev_err(trf->dev, "%s - addr: 0x%x, ret: %d\n", __func__, addr,
 511                                 ret);
 512         return ret;
 513 }
 514
 515 static int trf7970a_write(struct trf7970a *trf, u8 reg, u8 val)
 516 {
 517         u8 buf[2] = { reg, val };
 518         int ret;
 519
 520         dev_dbg(trf->dev, "write(0x%x): 0x%x\n", reg, val);
 521
 522         ret = spi_write(trf->spi, buf, 2);
 523         if (ret)
 524                 dev_err(trf->dev, "%s - write: 0x%x 0x%x, ret: %d\n", __func__,
 525                                 buf[0], buf[1], ret);
 526
 527         return ret;
 528 }
 529
 530 static int trf7970a_read_irqstatus(struct trf7970a *trf, u8 *status)
 531 {
 532         int ret;
 533         u8 buf[2];
 534         u8 addr;
 535
 536         addr = TRF7970A_IRQ_STATUS | TRF7970A_CMD_BIT_RW;
 537
 538         if (trf->quirks & TRF7970A_QUIRK_IRQ_STATUS_READ) {
 539                 addr |= TRF7970A_CMD_BIT_CONTINUOUS;
 540                 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 541         } else {
 542                 ret = spi_write_then_read(trf->spi, &addr, 1, buf, 1);
 543         }
 544
 545         if (ret)
 546                 dev_err(trf->dev, "%s - irqstatus: Status read failed: %d\n",
 547                                 __func__, ret);
 548         else
 549                 *status = buf[0];
 550
 551         return ret;
 552 }
 553
 554 static int trf7970a_read_target_proto(struct trf7970a *trf, u8 *target_proto)
 555 {
 556         int ret;
 557         u8 buf[2];
 558         u8 addr;
 559
 560         addr = TRF79070A_NFC_TARGET_PROTOCOL | TRF7970A_CMD_BIT_RW |
 561                 TRF7970A_CMD_BIT_CONTINUOUS;
 562
 563         ret = spi_write_then_read(trf->spi, &addr, 1, buf, 2);
 564         if (ret)
 565                 dev_err(trf->dev, "%s - target_proto: Read failed: %d\n",
 566                                 __func__, ret);
 567         else
 568                 *target_proto = buf[0];
 569
 570         return ret;
 571 }
 572
 573 static int trf7970a_mode_detect(struct trf7970a *trf, u8 *rf_tech)
 574 {
 575         int ret;
 576         u8 target_proto, tech;
 577
 578         ret = trf7970a_read_target_proto(trf, &target_proto);
 579         if (ret)
 580                 return ret;
 581
 582         switch (target_proto) {
 583         case TRF79070A_NFC_TARGET_PROTOCOL_106A:
 584                 tech = NFC_DIGITAL_RF_TECH_106A;
 585                 break;
 586         case TRF79070A_NFC_TARGET_PROTOCOL_106B:
 587                 tech = NFC_DIGITAL_RF_TECH_106B;
 588                 break;
 589         case TRF79070A_NFC_TARGET_PROTOCOL_212F:
 590                 tech = NFC_DIGITAL_RF_TECH_212F;
 591                 break;
 592         case TRF79070A_NFC_TARGET_PROTOCOL_424F:
 593                 tech = NFC_DIGITAL_RF_TECH_424F;
 594                 break;
 595         default:
 596                 dev_dbg(trf->dev, "%s - mode_detect: target_proto: 0x%x\n",
 597                                 __func__, target_proto);
 598                 return -EIO;
 599         }
 600
 601         *rf_tech = tech;
 602
 603         return ret;
 604 }
 605
 606 static void trf7970a_send_upstream(struct trf7970a *trf)
 607 {
 608         dev_kfree_skb_any(trf->tx_skb);
 609         trf->tx_skb = NULL;
 610
 611         if (trf->rx_skb && !IS_ERR(trf->rx_skb) && !trf->aborting)
 612                 print_hex_dump_debug("trf7970a rx data: ", DUMP_PREFIX_NONE,
 613                                 16, 1, trf->rx_skb->data, trf->rx_skb->len,
 614                                 false);
 615
 616         trf->state = TRF7970A_ST_IDLE;
 617
 618         if (trf->aborting) {
 619                 dev_dbg(trf->dev, "Abort process complete\n");
 620
 621                 if (!IS_ERR(trf->rx_skb)) {
 622                         kfree_skb(trf->rx_skb);
 623                         trf->rx_skb = ERR_PTR(-ECANCELED);
 624                 }
 625
 626                 trf->aborting = false;
 627         }
 628
 629         trf->cb(trf->ddev, trf->cb_arg, trf->rx_skb);
 630
 631         trf->rx_skb = NULL;
 632 }
 633
 634 static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
 635 {
 636         dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
 637
 638         cancel_delayed_work(&trf->timeout_work);
 639
 640         kfree_skb(trf->rx_skb);
 641         trf->rx_skb = ERR_PTR(errno);
 642
 643         trf7970a_send_upstream(trf);
 644 }
 645
 646 static int trf7970a_transmit(struct trf7970a *trf, struct sk_buff *skb,
 647                 unsigned int len, u8 *prefix, unsigned int prefix_len)
 648 {
 649         struct spi_transfer t[2];
 650         struct spi_message m;
 651         unsigned int timeout;
 652         int ret;
 653
 654         print_hex_dump_debug("trf7970a tx data: ", DUMP_PREFIX_NONE,
 655                         16, 1, skb->data, len, false);
 656
 657         spi_message_init(&m);
 658
 659         memset(&t, 0, sizeof(t));
 660
 661         t[0].tx_buf = prefix;
 662         t[0].len = prefix_len;
 663         spi_message_add_tail(&t[0], &m);
 664
 665         t[1].tx_buf = skb->data;
 666         t[1].len = len;
 667         spi_message_add_tail(&t[1], &m);
 668
 669         ret = spi_sync(trf->spi, &m);
 670         if (ret) {
 671                 dev_err(trf->dev, "%s - Can't send tx data: %d\n", __func__,
 672                                 ret);
 673                 return ret;
 674         }
 675
 676         skb_pull(skb, len);
 677
 678         if (skb->len > 0) {
 679                 trf->state = TRF7970A_ST_WAIT_FOR_TX_FIFO;
 680                 timeout = TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT;
 681         } else {
 682                 if (trf->issue_eof) {
 683                         trf->state = TRF7970A_ST_WAIT_TO_ISSUE_EOF;
 684                         timeout = TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF;
 685                 } else {
 686                         trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
 687
 688                         if (!trf->timeout)
 689                                 timeout = TRF7970A_WAIT_FOR_TX_IRQ;
 690                         else
 691                                 timeout = trf->timeout;
 692                 }
 693         }
 694
 695         dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n", timeout,
 696                         trf->state);
 697
 698         schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
 699
 700         return 0;
 701 }
 702
 703 static void trf7970a_fill_fifo(struct trf7970a *trf)
 704 {
 705         struct sk_buff *skb = trf->tx_skb;
 706         unsigned int len;
 707         int ret;
 708         u8 fifo_bytes;
 709         u8 prefix;
 710
 711         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 712         if (ret) {
 713                 trf7970a_send_err_upstream(trf, ret);
 714                 return;
 715         }
 716
 717         dev_dbg(trf->dev, "Filling FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 718
 719         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 720
 721         /* Calculate how much more data can be written to the fifo */
 722         len = TRF7970A_FIFO_SIZE - fifo_bytes;
 723         if (!len) {
 724                 schedule_delayed_work(&trf->timeout_work,
 725                         msecs_to_jiffies(TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT));
 726                 return;
 727         }
 728
 729         len = min(skb->len, len);
 730
 731         prefix = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_FIFO_IO_REGISTER;
 732
 733         ret = trf7970a_transmit(trf, skb, len, &prefix, sizeof(prefix));
 734         if (ret)
 735                 trf7970a_send_err_upstream(trf, ret);
 736 }
 737
 738 static void trf7970a_drain_fifo(struct trf7970a *trf, u8 status)
 739 {
 740         struct sk_buff *skb = trf->rx_skb;
 741         int ret;
 742         u8 fifo_bytes;
 743
 744         if (status & TRF7970A_IRQ_STATUS_ERROR) {
 745                 trf7970a_send_err_upstream(trf, -EIO);
 746                 return;
 747         }
 748
 749         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 750         if (ret) {
 751                 trf7970a_send_err_upstream(trf, ret);
 752                 return;
 753         }
 754
 755         dev_dbg(trf->dev, "Draining FIFO - fifo_bytes: 0x%x\n", fifo_bytes);
 756
 757         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 758
 759         if (!fifo_bytes)
 760                 goto no_rx_data;
 761
 762         if (fifo_bytes > skb_tailroom(skb)) {
 763                 skb = skb_copy_expand(skb, skb_headroom(skb),
 764                                 max_t(int, fifo_bytes,
 765                                         TRF7970A_RX_SKB_ALLOC_SIZE),
 766                                 GFP_KERNEL);
 767                 if (!skb) {
 768                         trf7970a_send_err_upstream(trf, -ENOMEM);
 769                         return;
 770                 }
 771
 772                 kfree_skb(trf->rx_skb);
 773                 trf->rx_skb = skb;
 774         }
 775
 776         ret = trf7970a_read_cont(trf, TRF7970A_FIFO_IO_REGISTER,
 777                         skb_put(skb, fifo_bytes), fifo_bytes);
 778         if (ret) {
 779                 trf7970a_send_err_upstream(trf, ret);
 780                 return;
 781         }
 782
 783         /* If received Type 2 ACK/NACK, shift right 4 bits and pass up */
 784         if ((trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T) && (skb->len == 1) &&
 785                         (trf->special_fcn_reg1 ==
 786                                  TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX)) {
 787                 skb->data[0] >>= 4;
 788                 status = TRF7970A_IRQ_STATUS_SRX;
 789         } else {
 790                 trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA_CONT;
 791
 792                 ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS, &fifo_bytes);
 793                 if (ret) {
 794                         trf7970a_send_err_upstream(trf, ret);
 795                         return;
 796                 }
 797
 798                 fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 799
 800                 /* If there are bytes in the FIFO, set status to '0' so
 801                  * the if stmt below doesn't fire and the driver will wait
 802                  * for the trf7970a to generate another RX interrupt.
 803                  */
 804                 if (fifo_bytes)
 805                         status = 0;
 806         }
 807
 808 no_rx_data:
 809         if (status == TRF7970A_IRQ_STATUS_SRX) { /* Receive complete */
 810                 trf7970a_send_upstream(trf);
 811                 return;
 812         }
 813
 814         dev_dbg(trf->dev, "Setting timeout for %d ms\n",
 815                         TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT);
 816
 817         schedule_delayed_work(&trf->timeout_work,
 818                         msecs_to_jiffies(TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT));
 819 }
 820
 821 static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 822 {
 823         struct trf7970a *trf = dev_id;
 824         int ret;
 825         u8 status, fifo_bytes, iso_ctrl;
 826
 827         mutex_lock(&trf->lock);
 828
 829         if (trf->state == TRF7970A_ST_RF_OFF) {
 830                 mutex_unlock(&trf->lock);
 831                 return IRQ_NONE;
 832         }
 833
 834         ret = trf7970a_read_irqstatus(trf, &status);
 835         if (ret) {
 836                 mutex_unlock(&trf->lock);
 837                 return IRQ_NONE;
 838         }
 839
 840         dev_dbg(trf->dev, "IRQ - state: %d, status: 0x%x\n", trf->state,
 841                         status);
 842
 843         if (!status) {
 844                 mutex_unlock(&trf->lock);
 845                 return IRQ_NONE;
 846         }
 847
 848         switch (trf->state) {
 849         case TRF7970A_ST_IDLE:
 850         case TRF7970A_ST_IDLE_RX_BLOCKED:
 851                 /* If initiator and getting interrupts caused by RF noise,
 852                  * turn off the receiver to avoid unnecessary interrupts.
 853                  * It will be turned back on in trf7970a_send_cmd() when
 854                  * the next command is issued.
 855                  */
 856                 if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
 857                         trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
 858                         trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
 859                 }
 860
 861                 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 862                 break;
 863         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
 864                 if (status & TRF7970A_IRQ_STATUS_TX) {
 865                         trf->ignore_timeout =
 866                                 !cancel_delayed_work(&trf->timeout_work);
 867                         trf7970a_fill_fifo(trf);
 868                 } else {
 869                         trf7970a_send_err_upstream(trf, -EIO);
 870                 }
 871                 break;
 872         case TRF7970A_ST_WAIT_FOR_RX_DATA:
 873         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
 874                 if (status & TRF7970A_IRQ_STATUS_SRX) {
 875                         trf->ignore_timeout =
 876                                 !cancel_delayed_work(&trf->timeout_work);
 877                         trf7970a_drain_fifo(trf, status);
 878                 } else if (status & TRF7970A_IRQ_STATUS_FIFO) {
 879                         ret = trf7970a_read(trf, TRF7970A_FIFO_STATUS,
 880                                         &fifo_bytes);
 881
 882                         fifo_bytes &= ~TRF7970A_FIFO_STATUS_OVERFLOW;
 883
 884                         if (ret)
 885                                 trf7970a_send_err_upstream(trf, ret);
 886                         else if (!fifo_bytes)
 887                                 trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 888                 } else if ((status == TRF7970A_IRQ_STATUS_TX) ||
 889                                 (!trf->is_initiator &&
 890                                  (status == (TRF7970A_IRQ_STATUS_TX |
 891                                              TRF7970A_IRQ_STATUS_NFC_RF)))) {
 892                         trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 893
 894                         if (!trf->timeout) {
 895                                 trf->ignore_timeout = !cancel_delayed_work(
 896                                                 &trf->timeout_work);
 897                                 trf->rx_skb = ERR_PTR(0);
 898                                 trf7970a_send_upstream(trf);
 899                                 break;
 900                         }
 901
 902                         if (trf->is_initiator)
 903                                 break;
 904
 905                         iso_ctrl = trf->iso_ctrl;
 906
 907                         switch (trf->framing) {
 908                         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
 909                                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
 910                                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
 911                                 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 912                                 break;
 913                         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
 914                                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
 915                                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
 916                                 trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
 917                                 break;
 918                         case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
 919                                 ret = trf7970a_write(trf,
 920                                         TRF7970A_SPECIAL_FCN_REG1,
 921                                         TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
 922                                 if (ret)
 923                                         goto err_unlock_exit;
 924
 925                                 trf->special_fcn_reg1 =
 926                                         TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
 927                                 break;
 928                         default:
 929                                 break;
 930                         }
 931
 932                         if (iso_ctrl != trf->iso_ctrl) {
 933                                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
 934                                                 iso_ctrl);
 935                                 if (ret)
 936                                         goto err_unlock_exit;
 937
 938                                 trf->iso_ctrl = iso_ctrl;
 939                         }
 940                 } else {
 941                         trf7970a_send_err_upstream(trf, -EIO);
 942                 }
 943                 break;
 944         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
 945                 if (status != TRF7970A_IRQ_STATUS_TX)
 946                         trf7970a_send_err_upstream(trf, -EIO);
 947                 break;
 948         case TRF7970A_ST_LISTENING:
 949                 if (status & TRF7970A_IRQ_STATUS_SRX) {
 950                         trf->ignore_timeout =
 951                                 !cancel_delayed_work(&trf->timeout_work);
 952                         trf7970a_drain_fifo(trf, status);
 953                 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 954                         trf7970a_send_err_upstream(trf, -EIO);
 955                 }
 956                 break;
 957         case TRF7970A_ST_LISTENING_MD:
 958                 if (status & TRF7970A_IRQ_STATUS_SRX) {
 959                         trf->ignore_timeout =
 960                                 !cancel_delayed_work(&trf->timeout_work);
 961
 962                         ret = trf7970a_mode_detect(trf, &trf->md_rf_tech);
 963                         if (ret) {
 964                                 trf7970a_send_err_upstream(trf, ret);
 965                         } else {
 966                                 trf->state = TRF7970A_ST_LISTENING;
 967                                 trf7970a_drain_fifo(trf, status);
 968                         }
 969                 } else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
 970                         trf7970a_send_err_upstream(trf, -EIO);
 971                 }
 972                 break;
 973         default:
 974                 dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
 975                                 __func__, trf->state);
 976         }
 977
 978 err_unlock_exit:
 979         mutex_unlock(&trf->lock);
 980         return IRQ_HANDLED;
 981 }
 982
 983 static void trf7970a_issue_eof(struct trf7970a *trf)
 984 {
 985         int ret;
 986
 987         dev_dbg(trf->dev, "Issuing EOF\n");
 988
 989         ret = trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 990         if (ret)
 991                 trf7970a_send_err_upstream(trf, ret);
 992
 993         ret = trf7970a_cmd(trf, TRF7970A_CMD_EOF);
 994         if (ret)
 995                 trf7970a_send_err_upstream(trf, ret);
 996
 997         trf->state = TRF7970A_ST_WAIT_FOR_RX_DATA;
 998
 999         dev_dbg(trf->dev, "Setting timeout for %d ms, state: %d\n",
1000                         trf->timeout, trf->state);
1001
1002         schedule_delayed_work(&trf->timeout_work,
1003                         msecs_to_jiffies(trf->timeout));
1004 }
1005
1006 static void trf7970a_timeout_work_handler(struct work_struct *work)
1007 {
1008         struct trf7970a *trf = container_of(work, struct trf7970a,
1009                         timeout_work.work);
1010
1011         dev_dbg(trf->dev, "Timeout - state: %d, ignore_timeout: %d\n",
1012                         trf->state, trf->ignore_timeout);
1013
1014         mutex_lock(&trf->lock);
1015
1016         if (trf->ignore_timeout)
1017                 trf->ignore_timeout = false;
1018         else if (trf->state == TRF7970A_ST_WAIT_FOR_RX_DATA_CONT)
1019                 trf7970a_drain_fifo(trf, TRF7970A_IRQ_STATUS_SRX);
1020         else if (trf->state == TRF7970A_ST_WAIT_TO_ISSUE_EOF)
1021                 trf7970a_issue_eof(trf);
1022         else
1023                 trf7970a_send_err_upstream(trf, -ETIMEDOUT);
1024
1025         mutex_unlock(&trf->lock);
1026 }
1027
1028 static int trf7970a_init(struct trf7970a *trf)
1029 {
1030         int ret;
1031
1032         dev_dbg(trf->dev, "Initializing device - state: %d\n", trf->state);
1033
1034         ret = trf7970a_cmd(trf, TRF7970A_CMD_SOFT_INIT);
1035         if (ret)
1036                 goto err_out;
1037
1038         ret = trf7970a_cmd(trf, TRF7970A_CMD_IDLE);
1039         if (ret)
1040                 goto err_out;
1041
1042         usleep_range(1000, 2000);
1043
1044         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1045
1046         ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL, 0);
1047         if (ret)
1048                 goto err_out;
1049
1050         trf->modulator_sys_clk_ctrl = 0;
1051
1052         ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
1053                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
1054                         TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
1055         if (ret)
1056                 goto err_out;
1057
1058         ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1, 0);
1059         if (ret)
1060                 goto err_out;
1061
1062         trf->special_fcn_reg1 = 0;
1063
1064         trf->iso_ctrl = 0xff;
1065         return 0;
1066
1067 err_out:
1068         dev_dbg(trf->dev, "Couldn't init device: %d\n", ret);
1069         return ret;
1070 }
1071
1072 static void trf7970a_switch_rf_off(struct trf7970a *trf)
1073 {
1074         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1075                         (trf->state == TRF7970A_ST_RF_OFF))
1076                 return;
1077
1078         dev_dbg(trf->dev, "Switching rf off\n");
1079
1080         trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
1081
1082         trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
1083
1084         trf->aborting = false;
1085         trf->state = TRF7970A_ST_RF_OFF;
1086
1087         pm_runtime_mark_last_busy(trf->dev);
1088         pm_runtime_put_autosuspend(trf->dev);
1089 }
1090
1091 static int trf7970a_switch_rf_on(struct trf7970a *trf)
1092 {
1093         int ret;
1094
1095         dev_dbg(trf->dev, "Switching rf on\n");
1096
1097         pm_runtime_get_sync(trf->dev);
1098
1099         if (trf->state != TRF7970A_ST_RF_OFF) { /* Power on, RF off */
1100                 dev_err(trf->dev, "%s - Incorrect state: %d\n", __func__,
1101                                 trf->state);
1102                 return -EINVAL;
1103         }
1104
1105         ret = trf7970a_init(trf);
1106         if (ret) {
1107                 dev_err(trf->dev, "%s - Can't initialize: %d\n", __func__, ret);
1108                 return ret;
1109         }
1110
1111         trf->state = TRF7970A_ST_IDLE;
1112
1113         return 0;
1114 }
1115
1116 static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
1117 {
1118         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1119         int ret = 0;
1120
1121         dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
1122
1123         mutex_lock(&trf->lock);
1124
1125         if (on) {
1126                 switch (trf->state) {
1127                 case TRF7970A_ST_PWR_OFF:
1128                 case TRF7970A_ST_RF_OFF:
1129                         ret = trf7970a_switch_rf_on(trf);
1130                         break;
1131                 case TRF7970A_ST_IDLE:
1132                 case TRF7970A_ST_IDLE_RX_BLOCKED:
1133                         break;
1134                 default:
1135                         dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1136                                         __func__, trf->state, on);
1137                         trf7970a_switch_rf_off(trf);
1138                         ret = -EINVAL;
1139                 }
1140         } else {
1141                 switch (trf->state) {
1142                 case TRF7970A_ST_PWR_OFF:
1143                 case TRF7970A_ST_RF_OFF:
1144                         break;
1145                 default:
1146                         dev_err(trf->dev, "%s - Invalid request: %d %d\n",
1147                                         __func__, trf->state, on);
1148                         ret = -EINVAL;
1149                         /* FALLTHROUGH */
1150                 case TRF7970A_ST_IDLE:
1151                 case TRF7970A_ST_IDLE_RX_BLOCKED:
1152                 case TRF7970A_ST_WAIT_FOR_RX_DATA:
1153                 case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1154                         trf7970a_switch_rf_off(trf);
1155                 }
1156         }
1157
1158         mutex_unlock(&trf->lock);
1159         return ret;
1160 }
1161
1162 static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
1163 {
1164         int ret = 0;
1165
1166         dev_dbg(trf->dev, "rf technology: %d\n", tech);
1167
1168         switch (tech) {
1169         case NFC_DIGITAL_RF_TECH_106A:
1170                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
1171                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1172                 trf->guard_time = TRF7970A_GUARD_TIME_NFCA;
1173                 break;
1174         case NFC_DIGITAL_RF_TECH_106B:
1175                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
1176                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1177                 trf->guard_time = TRF7970A_GUARD_TIME_NFCB;
1178                 break;
1179         case NFC_DIGITAL_RF_TECH_212F:
1180                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
1181                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1182                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1183                 break;
1184         case NFC_DIGITAL_RF_TECH_424F:
1185                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
1186                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1187                 trf->guard_time = TRF7970A_GUARD_TIME_NFCF;
1188                 break;
1189         case NFC_DIGITAL_RF_TECH_ISO15693:
1190                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1191                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1192                 trf->guard_time = TRF7970A_GUARD_TIME_15693;
1193                 break;
1194         default:
1195                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1196                 return -EINVAL;
1197         }
1198
1199         trf->technology = tech;
1200
1201         /* If in initiator mode and not changing the RF tech due to a
1202          * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
1203          * trf7970a_init()), clear the NFC Target Detection Level register
1204          * due to erratum.
1205          */
1206         if (trf->iso_ctrl == 0xff)
1207                 ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
1208
1209         return ret;
1210 }
1211
1212 static int trf7970a_is_rf_field(struct trf7970a *trf, bool *is_rf_field)
1213 {
1214         int ret;
1215         u8 rssi;
1216
1217         ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1218                         trf->chip_status_ctrl | TRF7970A_CHIP_STATUS_REC_ON);
1219         if (ret)
1220                 return ret;
1221
1222         ret = trf7970a_cmd(trf, TRF7970A_CMD_TEST_EXT_RF);
1223         if (ret)
1224                 return ret;
1225
1226         usleep_range(50, 60);
1227
1228         ret = trf7970a_read(trf, TRF7970A_RSSI_OSC_STATUS, &rssi);
1229         if (ret)
1230                 return ret;
1231
1232         ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1233                         trf->chip_status_ctrl);
1234         if (ret)
1235                 return ret;
1236
1237         if (rssi & TRF7970A_RSSI_OSC_STATUS_RSSI_MASK)
1238                 *is_rf_field = true;
1239         else
1240                 *is_rf_field = false;
1241
1242         return 0;
1243 }
1244
1245 static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
1246 {
1247         u8 iso_ctrl = trf->iso_ctrl_tech;
1248         bool is_rf_field = false;
1249         int ret;
1250
1251         dev_dbg(trf->dev, "framing: %d\n", framing);
1252
1253         switch (framing) {
1254         case NFC_DIGITAL_FRAMING_NFCA_SHORT:
1255         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1256                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1257                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1258                 break;
1259         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1260         case NFC_DIGITAL_FRAMING_NFCA_T4T:
1261         case NFC_DIGITAL_FRAMING_NFCB:
1262         case NFC_DIGITAL_FRAMING_NFCB_T4T:
1263         case NFC_DIGITAL_FRAMING_NFCF:
1264         case NFC_DIGITAL_FRAMING_NFCF_T3T:
1265         case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
1266         case NFC_DIGITAL_FRAMING_ISO15693_T5T:
1267         case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1268         case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1269                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1270                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1271                 break;
1272         case NFC_DIGITAL_FRAMING_NFCA_T2T:
1273                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1274                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1275                 break;
1276         default:
1277                 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1278                 return -EINVAL;
1279         }
1280
1281         trf->framing = framing;
1282
1283         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1284                 ret = trf7970a_is_rf_field(trf, &is_rf_field);
1285                 if (ret)
1286                         return ret;
1287
1288                 if (is_rf_field)
1289                         return -EBUSY;
1290         }
1291
1292         if (iso_ctrl != trf->iso_ctrl) {
1293                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1294                 if (ret)
1295                         return ret;
1296
1297                 trf->iso_ctrl = iso_ctrl;
1298
1299                 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1300                                 trf->modulator_sys_clk_ctrl);
1301                 if (ret)
1302                         return ret;
1303         }
1304
1305         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1306                 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1307                                 trf->chip_status_ctrl |
1308                                         TRF7970A_CHIP_STATUS_RF_ON);
1309                 if (ret)
1310                         return ret;
1311
1312                 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1313
1314                 usleep_range(trf->guard_time, trf->guard_time + 1000);
1315         }
1316
1317         return 0;
1318 }
1319
1320 static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
1321                 int param)
1322 {
1323         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1324         int ret;
1325
1326         dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1327
1328         mutex_lock(&trf->lock);
1329
1330         trf->is_initiator = true;
1331
1332         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1333                         (trf->state == TRF7970A_ST_RF_OFF)) {
1334                 ret = trf7970a_switch_rf_on(trf);
1335                 if (ret)
1336                         goto err_unlock;
1337         }
1338
1339         switch (type) {
1340         case NFC_DIGITAL_CONFIG_RF_TECH:
1341                 ret = trf7970a_in_config_rf_tech(trf, param);
1342                 break;
1343         case NFC_DIGITAL_CONFIG_FRAMING:
1344                 ret = trf7970a_in_config_framing(trf, param);
1345                 break;
1346         default:
1347                 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1348                 ret = -EINVAL;
1349         }
1350
1351 err_unlock:
1352         mutex_unlock(&trf->lock);
1353         return ret;
1354 }
1355
1356 static int trf7970a_is_iso15693_write_or_lock(u8 cmd)
1357 {
1358         switch (cmd) {
1359         case ISO15693_CMD_WRITE_SINGLE_BLOCK:
1360         case ISO15693_CMD_LOCK_BLOCK:
1361         case ISO15693_CMD_WRITE_MULTIPLE_BLOCK:
1362         case ISO15693_CMD_WRITE_AFI:
1363         case ISO15693_CMD_LOCK_AFI:
1364         case ISO15693_CMD_WRITE_DSFID:
1365         case ISO15693_CMD_LOCK_DSFID:
1366                 return 1;
1367                 break;
1368         default:
1369                 return 0;
1370         }
1371 }
1372
1373 static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
1374 {
1375         u8 *req = skb->data;
1376         u8 special_fcn_reg1, iso_ctrl;
1377         int ret;
1378
1379         trf->issue_eof = false;
1380
1381         /* When issuing Type 2 read command, make sure the '4_bit_RX' bit in
1382          * special functions register 1 is cleared; otherwise, its a write or
1383          * sector select command and '4_bit_RX' must be set.
1384          *
1385          * When issuing an ISO 15693 command, inspect the flags byte to see
1386          * what speed to use.  Also, remember if the OPTION flag is set on
1387          * a Type 5 write or lock command so the driver will know that it
1388          * has to send an EOF in order to get a response.
1389          */
1390         if ((trf->technology == NFC_DIGITAL_RF_TECH_106A) &&
1391                         (trf->framing == NFC_DIGITAL_FRAMING_NFCA_T2T)) {
1392                 if (req[0] == NFC_T2T_CMD_READ)
1393                         special_fcn_reg1 = 0;
1394                 else
1395                         special_fcn_reg1 = TRF7970A_SPECIAL_FCN_REG1_4_BIT_RX;
1396
1397                 if (special_fcn_reg1 != trf->special_fcn_reg1) {
1398                         ret = trf7970a_write(trf, TRF7970A_SPECIAL_FCN_REG1,
1399                                         special_fcn_reg1);
1400                         if (ret)
1401                                 return ret;
1402
1403                         trf->special_fcn_reg1 = special_fcn_reg1;
1404                 }
1405         } else if (trf->technology == NFC_DIGITAL_RF_TECH_ISO15693) {
1406                 iso_ctrl = trf->iso_ctrl & ~TRF7970A_ISO_CTRL_RFID_SPEED_MASK;
1407
1408                 switch (req[0] & ISO15693_REQ_FLAG_SPEED_MASK) {
1409                 case 0x00:
1410                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_662;
1411                         break;
1412                 case ISO15693_REQ_FLAG_SUB_CARRIER:
1413                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_667a;
1414                         break;
1415                 case ISO15693_REQ_FLAG_DATA_RATE:
1416                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
1417                         break;
1418                 case (ISO15693_REQ_FLAG_SUB_CARRIER |
1419                                 ISO15693_REQ_FLAG_DATA_RATE):
1420                         iso_ctrl |= TRF7970A_ISO_CTRL_15693_DBL_1OF4_2669;
1421                         break;
1422                 }
1423
1424                 if (iso_ctrl != trf->iso_ctrl) {
1425                         ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1426                         if (ret)
1427                                 return ret;
1428
1429                         trf->iso_ctrl = iso_ctrl;
1430                 }
1431
1432                 if ((trf->framing == NFC_DIGITAL_FRAMING_ISO15693_T5T) &&
1433                                 trf7970a_is_iso15693_write_or_lock(req[1]) &&
1434                                 (req[0] & ISO15693_REQ_FLAG_OPTION))
1435                         trf->issue_eof = true;
1436         }
1437
1438         return 0;
1439 }
1440
1441 static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
1442                 struct sk_buff *skb, u16 timeout,
1443                 nfc_digital_cmd_complete_t cb, void *arg)
1444 {
1445         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1446         u8 prefix[5];
1447         unsigned int len;
1448         int ret;
1449         u8 status;
1450
1451         dev_dbg(trf->dev, "New request - state: %d, timeout: %d ms, len: %d\n",
1452                         trf->state, timeout, skb->len);
1453
1454         if (skb->len > TRF7970A_TX_MAX)
1455                 return -EINVAL;
1456
1457         mutex_lock(&trf->lock);
1458
1459         if ((trf->state != TRF7970A_ST_IDLE) &&
1460                         (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1461                 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1462                                 trf->state);
1463                 ret = -EIO;
1464                 goto out_err;
1465         }
1466
1467         if (trf->aborting) {
1468                 dev_dbg(trf->dev, "Abort process complete\n");
1469                 trf->aborting = false;
1470                 ret = -ECANCELED;
1471                 goto out_err;
1472         }
1473
1474         if (timeout) {
1475                 trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1476                                 GFP_KERNEL);
1477                 if (!trf->rx_skb) {
1478                         dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1479                         ret = -ENOMEM;
1480                         goto out_err;
1481                 }
1482         }
1483
1484         if (trf->state == TRF7970A_ST_IDLE_RX_BLOCKED) {
1485                 ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1486                 if (ret)
1487                         goto out_err;
1488
1489                 trf->state = TRF7970A_ST_IDLE;
1490         }
1491
1492         if (trf->is_initiator) {
1493                 ret = trf7970a_per_cmd_config(trf, skb);
1494                 if (ret)
1495                         goto out_err;
1496         }
1497
1498         trf->ddev = ddev;
1499         trf->tx_skb = skb;
1500         trf->cb = cb;
1501         trf->cb_arg = arg;
1502         trf->timeout = timeout;
1503         trf->ignore_timeout = false;
1504
1505         len = skb->len;
1506
1507         /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
1508          * on what the current framing is, the address of the TX length byte 1
1509          * register (0x1d), and the 2 byte length of the data to be transmitted.
1510          * That totals 5 bytes.
1511          */
1512         prefix[0] = TRF7970A_CMD_BIT_CTRL |
1513                         TRF7970A_CMD_BIT_OPCODE(TRF7970A_CMD_FIFO_RESET);
1514         prefix[1] = TRF7970A_CMD_BIT_CTRL |
1515                         TRF7970A_CMD_BIT_OPCODE(trf->tx_cmd);
1516         prefix[2] = TRF7970A_CMD_BIT_CONTINUOUS | TRF7970A_TX_LENGTH_BYTE1;
1517
1518         if (trf->framing == NFC_DIGITAL_FRAMING_NFCA_SHORT) {
1519                 prefix[3] = 0x00;
1520                 prefix[4] = 0x0f; /* 7 bits */
1521         } else {
1522                 prefix[3] = (len & 0xf00) >> 4;
1523                 prefix[3] |= ((len & 0xf0) >> 4);
1524                 prefix[4] = ((len & 0x0f) << 4);
1525         }
1526
1527         len = min_t(int, skb->len, TRF7970A_FIFO_SIZE);
1528
1529         /* Clear possible spurious interrupt */
1530         ret = trf7970a_read_irqstatus(trf, &status);
1531         if (ret)
1532                 goto out_err;
1533
1534         ret = trf7970a_transmit(trf, skb, len, prefix, sizeof(prefix));
1535         if (ret) {
1536                 kfree_skb(trf->rx_skb);
1537                 trf->rx_skb = NULL;
1538         }
1539
1540 out_err:
1541         mutex_unlock(&trf->lock);
1542         return ret;
1543 }
1544
1545 static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
1546 {
1547         int ret = 0;
1548
1549         dev_dbg(trf->dev, "rf technology: %d\n", tech);
1550
1551         switch (tech) {
1552         case NFC_DIGITAL_RF_TECH_106A:
1553                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1554                         TRF7970A_ISO_CTRL_NFC_CE |
1555                         TRF7970A_ISO_CTRL_NFC_CE_14443A;
1556                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
1557                 break;
1558         case NFC_DIGITAL_RF_TECH_212F:
1559                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1560                         TRF7970A_ISO_CTRL_NFC_NFCF_212;
1561                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1562                 break;
1563         case NFC_DIGITAL_RF_TECH_424F:
1564                 trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
1565                         TRF7970A_ISO_CTRL_NFC_NFCF_424;
1566                 trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
1567                 break;
1568         default:
1569                 dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
1570                 return -EINVAL;
1571         }
1572
1573         trf->technology = tech;
1574
1575         /* Normally we write the ISO_CTRL register in
1576          * trf7970a_tg_config_framing() because the framing can change
1577          * the value written.  However, when sending a PSL RES,
1578          * digital_tg_send_psl_res_complete() doesn't call
1579          * trf7970a_tg_config_framing() so we must write the register
1580          * here.
1581          */
1582         if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
1583                         (trf->iso_ctrl_tech != trf->iso_ctrl)) {
1584                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
1585                                 trf->iso_ctrl_tech);
1586
1587                 trf->iso_ctrl = trf->iso_ctrl_tech;
1588         }
1589
1590         return ret;
1591 }
1592
1593 /* Since this is a target routine, several of the framing calls are
1594  * made between receiving the request and sending the response so they
1595  * should take effect until after the response is sent.  This is accomplished
1596  * by skipping the ISO_CTRL register write here and doing it in the interrupt
1597  * handler.
1598  */
1599 static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
1600 {
1601         u8 iso_ctrl = trf->iso_ctrl_tech;
1602         int ret;
1603
1604         dev_dbg(trf->dev, "framing: %d\n", framing);
1605
1606         switch (framing) {
1607         case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
1608                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
1609                 iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
1610                 break;
1611         case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
1612         case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
1613         case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
1614                 /* These ones are applied in the interrupt handler */
1615                 iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
1616                 break;
1617         case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
1618                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1619                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1620                 break;
1621         case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
1622                 trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
1623                 iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
1624                 break;
1625         default:
1626                 dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
1627                 return -EINVAL;
1628         }
1629
1630         trf->framing = framing;
1631
1632         if (iso_ctrl != trf->iso_ctrl) {
1633                 ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
1634                 if (ret)
1635                         return ret;
1636
1637                 trf->iso_ctrl = iso_ctrl;
1638
1639                 ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
1640                                 trf->modulator_sys_clk_ctrl);
1641                 if (ret)
1642                         return ret;
1643         }
1644
1645         if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
1646                 ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
1647                                 trf->chip_status_ctrl |
1648                                         TRF7970A_CHIP_STATUS_RF_ON);
1649                 if (ret)
1650                         return ret;
1651
1652                 trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
1653         }
1654
1655         return 0;
1656 }
1657
1658 static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
1659                 int param)
1660 {
1661         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1662         int ret;
1663
1664         dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
1665
1666         mutex_lock(&trf->lock);
1667
1668         trf->is_initiator = false;
1669
1670         if ((trf->state == TRF7970A_ST_PWR_OFF) ||
1671                         (trf->state == TRF7970A_ST_RF_OFF)) {
1672                 ret = trf7970a_switch_rf_on(trf);
1673                 if (ret)
1674                         goto err_unlock;
1675         }
1676
1677         switch (type) {
1678         case NFC_DIGITAL_CONFIG_RF_TECH:
1679                 ret = trf7970a_tg_config_rf_tech(trf, param);
1680                 break;
1681         case NFC_DIGITAL_CONFIG_FRAMING:
1682                 ret = trf7970a_tg_config_framing(trf, param);
1683                 break;
1684         default:
1685                 dev_dbg(trf->dev, "Unknown type: %d\n", type);
1686                 ret = -EINVAL;
1687         }
1688
1689 err_unlock:
1690         mutex_unlock(&trf->lock);
1691         return ret;
1692 }
1693
1694 static int _trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1695                 nfc_digital_cmd_complete_t cb, void *arg, bool mode_detect)
1696 {
1697         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1698         int ret;
1699
1700         mutex_lock(&trf->lock);
1701
1702         if ((trf->state != TRF7970A_ST_IDLE) &&
1703                         (trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
1704                 dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
1705                                 trf->state);
1706                 ret = -EIO;
1707                 goto out_err;
1708         }
1709
1710         if (trf->aborting) {
1711                 dev_dbg(trf->dev, "Abort process complete\n");
1712                 trf->aborting = false;
1713                 ret = -ECANCELED;
1714                 goto out_err;
1715         }
1716
1717         trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
1718                         GFP_KERNEL);
1719         if (!trf->rx_skb) {
1720                 dev_dbg(trf->dev, "Can't alloc rx_skb\n");
1721                 ret = -ENOMEM;
1722                 goto out_err;
1723         }
1724
1725         ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
1726                         TRF7970A_RX_SPECIAL_SETTINGS_HBT |
1727                         TRF7970A_RX_SPECIAL_SETTINGS_M848 |
1728                         TRF7970A_RX_SPECIAL_SETTINGS_C424 |
1729                         TRF7970A_RX_SPECIAL_SETTINGS_C212);
1730         if (ret)
1731                 goto out_err;
1732
1733         ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
1734                         TRF7970A_REG_IO_CTRL_VRS(0x1));
1735         if (ret)
1736                 goto out_err;
1737
1738         ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
1739                         TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
1740         if (ret)
1741                 goto out_err;
1742
1743         ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
1744                         TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
1745         if (ret)
1746                 goto out_err;
1747
1748         trf->ddev = ddev;
1749         trf->cb = cb;
1750         trf->cb_arg = arg;
1751         trf->timeout = timeout;
1752         trf->ignore_timeout = false;
1753
1754         ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
1755         if (ret)
1756                 goto out_err;
1757
1758         trf->state = mode_detect ? TRF7970A_ST_LISTENING_MD :
1759                                    TRF7970A_ST_LISTENING;
1760
1761         schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
1762
1763 out_err:
1764         mutex_unlock(&trf->lock);
1765         return ret;
1766 }
1767
1768 static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
1769                 nfc_digital_cmd_complete_t cb, void *arg)
1770 {
1771         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1772
1773         dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
1774                         trf->state, timeout);
1775
1776         return _trf7970a_tg_listen(ddev, timeout, cb, arg, false);
1777 }
1778
1779 static int trf7970a_tg_listen_md(struct nfc_digital_dev *ddev,
1780                 u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
1781 {
1782         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1783         int ret;
1784
1785         dev_dbg(trf->dev, "Listen MD - state: %d, timeout: %d ms\n",
1786                         trf->state, timeout);
1787
1788         ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
1789                         NFC_DIGITAL_RF_TECH_106A);
1790         if (ret)
1791                 return ret;
1792
1793         ret = trf7970a_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1794                         NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
1795         if (ret)
1796                 return ret;
1797
1798         return _trf7970a_tg_listen(ddev, timeout, cb, arg, true);
1799 }
1800
1801 static int trf7970a_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
1802 {
1803         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1804
1805         dev_dbg(trf->dev, "Get RF Tech - state: %d, rf_tech: %d\n",
1806                         trf->state, trf->md_rf_tech);
1807
1808         *rf_tech = trf->md_rf_tech;
1809
1810         return 0;
1811 }
1812
1813 static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
1814 {
1815         struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
1816
1817         dev_dbg(trf->dev, "Abort process initiated\n");
1818
1819         mutex_lock(&trf->lock);
1820
1821         switch (trf->state) {
1822         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1823         case TRF7970A_ST_WAIT_FOR_RX_DATA:
1824         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1825         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1826                 trf->aborting = true;
1827                 break;
1828         case TRF7970A_ST_LISTENING:
1829                 trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
1830                 trf7970a_send_err_upstream(trf, -ECANCELED);
1831                 dev_dbg(trf->dev, "Abort process complete\n");
1832                 break;
1833         default:
1834                 break;
1835         }
1836
1837         mutex_unlock(&trf->lock);
1838 }
1839
1840 static struct nfc_digital_ops trf7970a_nfc_ops = {
1841         .in_configure_hw        = trf7970a_in_configure_hw,
1842         .in_send_cmd            = trf7970a_send_cmd,
1843         .tg_configure_hw        = trf7970a_tg_configure_hw,
1844         .tg_send_cmd            = trf7970a_send_cmd,
1845         .tg_listen              = trf7970a_tg_listen,
1846         .tg_listen_md           = trf7970a_tg_listen_md,
1847         .tg_get_rf_tech         = trf7970a_tg_get_rf_tech,
1848         .switch_rf              = trf7970a_switch_rf,
1849         .abort_cmd              = trf7970a_abort_cmd,
1850 };
1851
1852 static int trf7970a_power_up(struct trf7970a *trf)
1853 {
1854         int ret;
1855
1856         dev_dbg(trf->dev, "Powering up - state: %d\n", trf->state);
1857
1858         if (trf->state != TRF7970A_ST_PWR_OFF)
1859                 return 0;
1860
1861         ret = regulator_enable(trf->regulator);
1862         if (ret) {
1863                 dev_err(trf->dev, "%s - Can't enable VIN: %d\n", __func__, ret);
1864                 return ret;
1865         }
1866
1867         usleep_range(5000, 6000);
1868
1869         if (!(trf->quirks & TRF7970A_QUIRK_EN2_MUST_STAY_LOW)) {
1870                 gpio_set_value(trf->en2_gpio, 1);
1871                 usleep_range(1000, 2000);
1872         }
1873
1874         gpio_set_value(trf->en_gpio, 1);
1875
1876         usleep_range(20000, 21000);
1877
1878         trf->state = TRF7970A_ST_RF_OFF;
1879
1880         return 0;
1881 }
1882
1883 static int trf7970a_power_down(struct trf7970a *trf)
1884 {
1885         int ret;
1886
1887         dev_dbg(trf->dev, "Powering down - state: %d\n", trf->state);
1888
1889         if (trf->state == TRF7970A_ST_PWR_OFF)
1890                 return 0;
1891
1892         if (trf->state != TRF7970A_ST_RF_OFF) {
1893                 dev_dbg(trf->dev, "Can't power down - not RF_OFF state (%d)\n",
1894                                 trf->state);
1895                 return -EBUSY;
1896         }
1897
1898         gpio_set_value(trf->en_gpio, 0);
1899         gpio_set_value(trf->en2_gpio, 0);
1900
1901         ret = regulator_disable(trf->regulator);
1902         if (ret)
1903                 dev_err(trf->dev, "%s - Can't disable VIN: %d\n", __func__,
1904                                 ret);
1905
1906         trf->state = TRF7970A_ST_PWR_OFF;
1907
1908         return ret;
1909 }
1910
1911 static int trf7970a_startup(struct trf7970a *trf)
1912 {
1913         int ret;
1914
1915         ret = trf7970a_power_up(trf);
1916         if (ret)
1917                 return ret;
1918
1919         pm_runtime_set_active(trf->dev);
1920         pm_runtime_enable(trf->dev);
1921         pm_runtime_mark_last_busy(trf->dev);
1922
1923         return 0;
1924 }
1925
1926 static void trf7970a_shutdown(struct trf7970a *trf)
1927 {
1928         switch (trf->state) {
1929         case TRF7970A_ST_WAIT_FOR_TX_FIFO:
1930         case TRF7970A_ST_WAIT_FOR_RX_DATA:
1931         case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
1932         case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
1933         case TRF7970A_ST_LISTENING:
1934                 trf7970a_send_err_upstream(trf, -ECANCELED);
1935                 /* FALLTHROUGH */
1936         case TRF7970A_ST_IDLE:
1937         case TRF7970A_ST_IDLE_RX_BLOCKED:
1938                 trf7970a_switch_rf_off(trf);
1939                 break;
1940         default:
1941                 break;
1942         }
1943
1944         pm_runtime_disable(trf->dev);
1945         pm_runtime_set_suspended(trf->dev);
1946
1947         trf7970a_power_down(trf);
1948 }
1949
1950 static int trf7970a_get_autosuspend_delay(struct device_node *np)
1951 {
1952         int autosuspend_delay, ret;
1953
1954         ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
1955         if (ret)
1956                 autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
1957
1958         return autosuspend_delay;
1959 }
1960
1961 static int trf7970a_get_vin_voltage_override(struct device_node *np,
1962                 u32 *vin_uvolts)
1963 {
1964         return of_property_read_u32(np, "vin-voltage-override", vin_uvolts);
1965 }
1966
1967 static int trf7970a_probe(struct spi_device *spi)
1968 {
1969         struct device_node *np = spi->dev.of_node;
1970         struct trf7970a *trf;
1971         int uvolts, autosuspend_delay, ret;
1972
1973         if (!np) {
1974                 dev_err(&spi->dev, "No Device Tree entry\n");
1975                 return -EINVAL;
1976         }
1977
1978         trf = devm_kzalloc(&spi->dev, sizeof(*trf), GFP_KERNEL);
1979         if (!trf)
1980                 return -ENOMEM;
1981
1982         trf->state = TRF7970A_ST_PWR_OFF;
1983         trf->dev = &spi->dev;
1984         trf->spi = spi;
1985
1986         spi->mode = SPI_MODE_1;
1987         spi->bits_per_word = 8;
1988
1989         ret = spi_setup(spi);
1990         if (ret < 0) {
1991                 dev_err(trf->dev, "Can't set up SPI Communication\n");
1992                 return ret;
1993         }
1994
1995         if (of_property_read_bool(np, "irq-status-read-quirk"))
1996                 trf->quirks |= TRF7970A_QUIRK_IRQ_STATUS_READ;
1997
1998         /* There are two enable pins - both must be present */
1999         trf->en_gpio = of_get_named_gpio(np, "ti,enable-gpios", 0);
2000         if (!gpio_is_valid(trf->en_gpio)) {
2001                 dev_err(trf->dev, "No EN GPIO property\n");
2002                 return trf->en_gpio;
2003         }
2004
2005         ret = devm_gpio_request_one(trf->dev, trf->en_gpio,
2006                         GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN");
2007         if (ret) {
2008                 dev_err(trf->dev, "Can't request EN GPIO: %d\n", ret);
2009                 return ret;
2010         }
2011
2012         trf->en2_gpio = of_get_named_gpio(np, "ti,enable-gpios", 1);
2013         if (!gpio_is_valid(trf->en2_gpio)) {
2014                 dev_err(trf->dev, "No EN2 GPIO property\n");
2015                 return trf->en2_gpio;
2016         }
2017
2018         ret = devm_gpio_request_one(trf->dev, trf->en2_gpio,
2019                         GPIOF_DIR_OUT | GPIOF_INIT_LOW, "trf7970a EN2");
2020         if (ret) {
2021                 dev_err(trf->dev, "Can't request EN2 GPIO: %d\n", ret);
2022                 return ret;
2023         }
2024
2025         if (of_property_read_bool(np, "en2-rf-quirk"))
2026                 trf->quirks |= TRF7970A_QUIRK_EN2_MUST_STAY_LOW;
2027
2028         ret = devm_request_threaded_irq(trf->dev, spi->irq, NULL,
2029                         trf7970a_irq, IRQF_TRIGGER_RISING | IRQF_ONESHOT,
2030                         "trf7970a", trf);
2031         if (ret) {
2032                 dev_err(trf->dev, "Can't request IRQ#%d: %d\n", spi->irq, ret);
2033                 return ret;
2034         }
2035
2036         mutex_init(&trf->lock);
2037         INIT_DELAYED_WORK(&trf->timeout_work, trf7970a_timeout_work_handler);
2038
2039         trf->regulator = devm_regulator_get(&spi->dev, "vin");
2040         if (IS_ERR(trf->regulator)) {
2041                 ret = PTR_ERR(trf->regulator);
2042                 dev_err(trf->dev, "Can't get VIN regulator: %d\n", ret);
2043                 goto err_destroy_lock;
2044         }
2045
2046         ret = regulator_enable(trf->regulator);
2047         if (ret) {
2048                 dev_err(trf->dev, "Can't enable VIN: %d\n", ret);
2049                 goto err_destroy_lock;
2050         }
2051
2052         ret = trf7970a_get_vin_voltage_override(np, &uvolts);
2053         if (ret)
2054                 uvolts = regulator_get_voltage(trf->regulator);
2055
2056         if (uvolts > 4000000)
2057                 trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
2058
2059         trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
2060                         TRF7970A_SUPPORTED_PROTOCOLS,
2061                         NFC_DIGITAL_DRV_CAPS_IN_CRC |
2062                                 NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
2063         if (!trf->ddev) {
2064                 dev_err(trf->dev, "Can't allocate NFC digital device\n");
2065                 ret = -ENOMEM;
2066                 goto err_disable_regulator;
2067         }
2068
2069         nfc_digital_set_parent_dev(trf->ddev, trf->dev);
2070         nfc_digital_set_drvdata(trf->ddev, trf);
2071         spi_set_drvdata(spi, trf);
2072
2073         autosuspend_delay = trf7970a_get_autosuspend_delay(np);
2074
2075         pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
2076         pm_runtime_use_autosuspend(trf->dev);
2077
2078         ret = trf7970a_startup(trf);
2079         if (ret)
2080                 goto err_free_ddev;
2081
2082         ret = nfc_digital_register_device(trf->ddev);
2083         if (ret) {
2084                 dev_err(trf->dev, "Can't register NFC digital device: %d\n",
2085                                 ret);
2086                 goto err_shutdown;
2087         }
2088
2089         return 0;
2090
2091 err_shutdown:
2092         trf7970a_shutdown(trf);
2093 err_free_ddev:
2094         nfc_digital_free_device(trf->ddev);
2095 err_disable_regulator:
2096         regulator_disable(trf->regulator);
2097 err_destroy_lock:
2098         mutex_destroy(&trf->lock);
2099         return ret;
2100 }
2101
2102 static int trf7970a_remove(struct spi_device *spi)
2103 {
2104         struct trf7970a *trf = spi_get_drvdata(spi);
2105
2106         mutex_lock(&trf->lock);
2107
2108         trf7970a_shutdown(trf);
2109
2110         mutex_unlock(&trf->lock);
2111
2112         nfc_digital_unregister_device(trf->ddev);
2113         nfc_digital_free_device(trf->ddev);
2114
2115         regulator_disable(trf->regulator);
2116
2117         mutex_destroy(&trf->lock);
2118
2119         return 0;
2120 }
2121
2122 #ifdef CONFIG_PM_SLEEP
2123 static int trf7970a_suspend(struct device *dev)
2124 {
2125         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2126         struct trf7970a *trf = spi_get_drvdata(spi);
2127
2128         dev_dbg(dev, "Suspend\n");
2129
2130         mutex_lock(&trf->lock);
2131
2132         trf7970a_shutdown(trf);
2133
2134         mutex_unlock(&trf->lock);
2135
2136         return 0;
2137 }
2138
2139 static int trf7970a_resume(struct device *dev)
2140 {
2141         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2142         struct trf7970a *trf = spi_get_drvdata(spi);
2143         int ret;
2144
2145         dev_dbg(dev, "Resume\n");
2146
2147         mutex_lock(&trf->lock);
2148
2149         ret = trf7970a_startup(trf);
2150
2151         mutex_unlock(&trf->lock);
2152
2153         return ret;
2154 }
2155 #endif
2156
2157 #ifdef CONFIG_PM
2158 static int trf7970a_pm_runtime_suspend(struct device *dev)
2159 {
2160         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2161         struct trf7970a *trf = spi_get_drvdata(spi);
2162         int ret;
2163
2164         dev_dbg(dev, "Runtime suspend\n");
2165
2166         mutex_lock(&trf->lock);
2167
2168         ret = trf7970a_power_down(trf);
2169
2170         mutex_unlock(&trf->lock);
2171
2172         return ret;
2173 }
2174
2175 static int trf7970a_pm_runtime_resume(struct device *dev)
2176 {
2177         struct spi_device *spi = container_of(dev, struct spi_device, dev);
2178         struct trf7970a *trf = spi_get_drvdata(spi);
2179         int ret;
2180
2181         dev_dbg(dev, "Runtime resume\n");
2182
2183         ret = trf7970a_power_up(trf);
2184         if (!ret)
2185                 pm_runtime_mark_last_busy(dev);
2186
2187         return ret;
2188 }
2189 #endif
2190
2191 static const struct dev_pm_ops trf7970a_pm_ops = {
2192         SET_SYSTEM_SLEEP_PM_OPS(trf7970a_suspend, trf7970a_resume)
2193         SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
2194                         trf7970a_pm_runtime_resume, NULL)
2195 };
2196
2197 static const struct spi_device_id trf7970a_id_table[] = {
2198         { "trf7970a", 0 },
2199         { }
2200 };
2201 MODULE_DEVICE_TABLE(spi, trf7970a_id_table);
2202
2203 static struct spi_driver trf7970a_spi_driver = {
2204         .probe          = trf7970a_probe,
2205         .remove         = trf7970a_remove,
2206         .id_table       = trf7970a_id_table,
2207         .driver         = {
2208                 .name   = "trf7970a",
2209                 .owner  = THIS_MODULE,
2210                 .pm     = &trf7970a_pm_ops,
2211         },
2212 };
2213
2214 module_spi_driver(trf7970a_spi_driver);
2215
2216 MODULE_AUTHOR("Mark A. Greer <mgreer@animalcreek.com>");
2217 MODULE_LICENSE("GPL v2");
2218 MODULE_DESCRIPTION("TI trf7970a RFID/NFC Transceiver Driver");