Merge branch 'tda998x-devel' of git://ftp.arm.linux.org.uk/~rmk/linux-cubox into...
[cascardo/linux.git] / drivers / nfc / trf7970a.c
index d9babe9..3b78b03 100644 (file)
@@ -16,6 +16,7 @@
 #include <linux/device.h>
 #include <linux/netdevice.h>
 #include <linux/interrupt.h>
+#include <linux/pm_runtime.h>
 #include <linux/nfc.h>
 #include <linux/skbuff.h>
 #include <linux/delay.h>
  * only the SRX bit set, it means that all of the data has been received
  * (once what's in the fifo has been read).  However, depending on timing
  * an interrupt status with only the SRX bit set may not be recived.  In
- * those cases, the timeout mechanism is used to wait 5 ms in case more
- * data arrives.  After 5 ms, it is assumed that all of the data has been
+ * those cases, the timeout mechanism is used to wait 20 ms in case more
+ * data arrives.  After 20 ms, it is assumed that all of the data has been
  * received and the accumulated rx data is sent upstream.  The
  * 'TRF7970A_ST_WAIT_FOR_RX_DATA_CONT' state is used for this purpose
  * (i.e., it indicates that some data has been received but we're not sure
  * if there is more coming so a timeout in this state means all data has
- * been received and there isn't an error).  The delay is 5 ms since delays
- * over 2 ms have been observed during testing (a little extra just in case).
+ * been received and there isn't an error).  The delay is 20 ms since delays
+ * of ~16 ms have been observed during testing.
  *
  * Type 2 write and sector select commands respond with a 4-bit ACK or NACK.
  * Having only 4 bits in the FIFO won't normally generate an interrupt so
 
 #define TRF7970A_SUPPORTED_PROTOCOLS \
                (NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |      \
+                NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
                 NFC_PROTO_ISO15693_MASK)
 
+#define TRF7970A_AUTOSUSPEND_DELAY             30000 /* 30 seconds */
+
 /* TX data must be prefixed with a FIFO reset cmd, a cmd that depends
  * on what the current framing is, the address of the TX length byte 1
  * register (0x1d), and the 2 byte length of the data to be transmitted.
 /* TX length is 3 nibbles long ==> 4KB - 1 bytes max */
 #define TRF7970A_TX_MAX                                (4096 - 1)
 
-#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT      5
+#define TRF7970A_WAIT_FOR_RX_DATA_TIMEOUT      20
 #define TRF7970A_WAIT_FOR_FIFO_DRAIN_TIMEOUT   3
 #define TRF7970A_WAIT_TO_ISSUE_ISO15693_EOF    20
 
@@ -330,13 +334,15 @@ struct trf7970a {
        struct regulator                *regulator;
        struct nfc_digital_dev          *ddev;
        u32                             quirks;
-       bool                            powering_up;
        bool                            aborting;
        struct sk_buff                  *tx_skb;
        struct sk_buff                  *rx_skb;
        nfc_digital_cmd_complete_t      cb;
        void                            *cb_arg;
+       u8                              chip_status_ctrl;
        u8                              iso_ctrl;
+       u8                              iso_ctrl_tech;
+       u8                              modulator_sys_clk_ctrl;
        u8                              special_fcn_reg1;
        int                             technology;
        int                             framing;
@@ -681,7 +687,9 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
                        trf->ignore_timeout =
                                !cancel_delayed_work(&trf->timeout_work);
                        trf7970a_drain_fifo(trf, status);
-               } else if (!(status & TRF7970A_IRQ_STATUS_TX)) {
+               } else if (status == TRF7970A_IRQ_STATUS_TX) {
+                       trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
+               } else {
                        trf7970a_send_err_upstream(trf, -EIO);
                }
                break;
@@ -757,8 +765,8 @@ static int trf7970a_init(struct trf7970a *trf)
        if (ret)
                goto err_out;
 
-       ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
-                       TRF7970A_MODULATOR_DEPTH_OOK);
+       /* Must clear NFC Target Detection Level reg due to erratum */
+       ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
        if (ret)
                goto err_out;
 
@@ -774,12 +782,7 @@ static int trf7970a_init(struct trf7970a *trf)
 
        trf->special_fcn_reg1 = 0;
 
-       ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
-                       TRF7970A_CHIP_STATUS_RF_ON |
-                               TRF7970A_CHIP_STATUS_VRS5_3);
-       if (ret)
-               goto err_out;
-
+       trf->iso_ctrl = 0xff;
        return 0;
 
 err_out:
@@ -791,53 +794,29 @@ static void trf7970a_switch_rf_off(struct trf7970a *trf)
 {
        dev_dbg(trf->dev, "Switching rf off\n");
 
-       gpio_set_value(trf->en_gpio, 0);
-       gpio_set_value(trf->en2_gpio, 0);
+       trf->chip_status_ctrl &= ~TRF7970A_CHIP_STATUS_RF_ON;
+
+       trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL, trf->chip_status_ctrl);
 
        trf->aborting = false;
        trf->state = TRF7970A_ST_OFF;
+
+       pm_runtime_mark_last_busy(trf->dev);
+       pm_runtime_put_autosuspend(trf->dev);
 }
 
-static int trf7970a_switch_rf_on(struct trf7970a *trf)
+static void trf7970a_switch_rf_on(struct trf7970a *trf)
 {
-       unsigned long delay;
-       int ret;
-
        dev_dbg(trf->dev, "Switching rf on\n");
 
-       if (trf->powering_up)
-               usleep_range(5000, 6000);
-
-       gpio_set_value(trf->en2_gpio, 1);
-       usleep_range(1000, 2000);
-       gpio_set_value(trf->en_gpio, 1);
+       pm_runtime_get_sync(trf->dev);
 
-       /* The delay between enabling the trf7970a and issuing the first
-        * command is significantly longer the very first time after powering
-        * up.  Make sure the longer delay is only done the first time.
-        */
-       if (trf->powering_up) {
-               delay = 20000;
-               trf->powering_up = false;
-       } else {
-               delay = 5000;
-       }
-
-       usleep_range(delay, delay + 1000);
-
-       ret = trf7970a_init(trf);
-       if (ret)
-               trf7970a_switch_rf_off(trf);
-       else
-               trf->state = TRF7970A_ST_IDLE;
-
-       return ret;
+       trf->state = TRF7970A_ST_IDLE;
 }
 
 static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
 {
        struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
-       int ret = 0;
 
        dev_dbg(trf->dev, "Switching RF - state: %d, on: %d\n", trf->state, on);
 
@@ -846,7 +825,7 @@ static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
        if (on) {
                switch (trf->state) {
                case TRF7970A_ST_OFF:
-                       ret = trf7970a_switch_rf_on(trf);
+                       trf7970a_switch_rf_on(trf);
                        break;
                case TRF7970A_ST_IDLE:
                case TRF7970A_ST_IDLE_RX_BLOCKED:
@@ -871,7 +850,7 @@ static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
        }
 
        mutex_unlock(&trf->lock);
-       return ret;
+       return 0;
 }
 
 static int trf7970a_config_rf_tech(struct trf7970a *trf, int tech)
@@ -882,10 +861,24 @@ static int trf7970a_config_rf_tech(struct trf7970a *trf, int tech)
 
        switch (tech) {
        case NFC_DIGITAL_RF_TECH_106A:
-               trf->iso_ctrl = TRF7970A_ISO_CTRL_14443A_106;
+               trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443A_106;
+               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+               break;
+       case NFC_DIGITAL_RF_TECH_106B:
+               trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_14443B_106;
+               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+               break;
+       case NFC_DIGITAL_RF_TECH_212F:
+               trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_212;
+               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+               break;
+       case NFC_DIGITAL_RF_TECH_424F:
+               trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_FELICA_424;
+               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
                break;
        case NFC_DIGITAL_RF_TECH_ISO15693:
-               trf->iso_ctrl = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
+               trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_15693_SGL_1OF4_2648;
+               trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
                break;
        default:
                dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
@@ -899,24 +892,31 @@ static int trf7970a_config_rf_tech(struct trf7970a *trf, int tech)
 
 static int trf7970a_config_framing(struct trf7970a *trf, int framing)
 {
+       u8 iso_ctrl = trf->iso_ctrl_tech;
+       int ret;
+
        dev_dbg(trf->dev, "framing: %d\n", framing);
 
        switch (framing) {
        case NFC_DIGITAL_FRAMING_NFCA_SHORT:
        case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
                trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
-               trf->iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
+               iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
                break;
        case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
        case NFC_DIGITAL_FRAMING_NFCA_T4T:
+       case NFC_DIGITAL_FRAMING_NFCB:
+       case NFC_DIGITAL_FRAMING_NFCB_T4T:
+       case NFC_DIGITAL_FRAMING_NFCF:
+       case NFC_DIGITAL_FRAMING_NFCF_T3T:
        case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
        case NFC_DIGITAL_FRAMING_ISO15693_T5T:
                trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
-               trf->iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
+               iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
                break;
        case NFC_DIGITAL_FRAMING_NFCA_T2T:
                trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
-               trf->iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
+               iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
                break;
        default:
                dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
@@ -925,24 +925,46 @@ static int trf7970a_config_framing(struct trf7970a *trf, int framing)
 
        trf->framing = framing;
 
-       return trf7970a_write(trf, TRF7970A_ISO_CTRL, trf->iso_ctrl);
+       if (iso_ctrl != trf->iso_ctrl) {
+               ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
+               if (ret)
+                       return ret;
+
+               trf->iso_ctrl = iso_ctrl;
+
+               ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
+                               trf->modulator_sys_clk_ctrl);
+               if (ret)
+                       return ret;
+       }
+
+       if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
+               ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
+                               trf->chip_status_ctrl |
+                                       TRF7970A_CHIP_STATUS_RF_ON);
+               if (ret)
+                       return ret;
+
+               trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
+
+               usleep_range(5000, 6000);
+       }
+
+       return 0;
 }
 
 static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
                int param)
 {
        struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
-       int ret = 0;
+       int ret;
 
        dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
 
        mutex_lock(&trf->lock);
 
-       if (trf->state == TRF7970A_ST_OFF) {
-               ret = trf7970a_switch_rf_on(trf);
-               if (ret)
-                       goto err_out;
-       }
+       if (trf->state == TRF7970A_ST_OFF)
+               trf7970a_switch_rf_on(trf);
 
        switch (type) {
        case NFC_DIGITAL_CONFIG_RF_TECH:
@@ -956,7 +978,6 @@ static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
                ret = -EINVAL;
        }
 
-err_out:
        mutex_unlock(&trf->lock);
        return ret;
 }
@@ -1191,7 +1212,18 @@ static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
        dev_dbg(trf->dev, "Abort process initiated\n");
 
        mutex_lock(&trf->lock);
-       trf->aborting = true;
+
+       switch (trf->state) {
+       case TRF7970A_ST_WAIT_FOR_TX_FIFO:
+       case TRF7970A_ST_WAIT_FOR_RX_DATA:
+       case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
+       case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
+               trf->aborting = true;
+               break;
+       default:
+               break;
+       }
+
        mutex_unlock(&trf->lock);
 }
 
@@ -1206,12 +1238,25 @@ static struct nfc_digital_ops trf7970a_nfc_ops = {
        .abort_cmd              = trf7970a_abort_cmd,
 };
 
+static int trf7970a_get_autosuspend_delay(struct device_node *np)
+{
+       int autosuspend_delay, ret;
+
+       ret = of_property_read_u32(np, "autosuspend-delay", &autosuspend_delay);
+       if (ret)
+               autosuspend_delay = TRF7970A_AUTOSUSPEND_DELAY;
+
+       of_node_put(np);
+
+       return autosuspend_delay;
+}
+
 static int trf7970a_probe(struct spi_device *spi)
 {
        struct device_node *np = spi->dev.of_node;
        const struct spi_device_id *id = spi_get_device_id(spi);
        struct trf7970a *trf;
-       int ret;
+       int uvolts, autosuspend_delay, ret;
 
        if (!np) {
                dev_err(&spi->dev, "No Device Tree entry\n");
@@ -1281,7 +1326,10 @@ static int trf7970a_probe(struct spi_device *spi)
                goto err_destroy_lock;
        }
 
-       trf->powering_up = true;
+       uvolts = regulator_get_voltage(trf->regulator);
+
+       if (uvolts > 4000000)
+               trf->chip_status_ctrl = TRF7970A_CHIP_STATUS_VRS5_3;
 
        trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
                        TRF7970A_SUPPORTED_PROTOCOLS,
@@ -1297,6 +1345,12 @@ static int trf7970a_probe(struct spi_device *spi)
        nfc_digital_set_drvdata(trf->ddev, trf);
        spi_set_drvdata(spi, trf);
 
+       autosuspend_delay = trf7970a_get_autosuspend_delay(np);
+
+       pm_runtime_set_autosuspend_delay(trf->dev, autosuspend_delay);
+       pm_runtime_use_autosuspend(trf->dev);
+       pm_runtime_enable(trf->dev);
+
        ret = nfc_digital_register_device(trf->ddev);
        if (ret) {
                dev_err(trf->dev, "Can't register NFC digital device: %d\n",
@@ -1307,6 +1361,7 @@ static int trf7970a_probe(struct spi_device *spi)
        return 0;
 
 err_free_ddev:
+       pm_runtime_disable(trf->dev);
        nfc_digital_free_device(trf->ddev);
 err_disable_regulator:
        regulator_disable(trf->regulator);
@@ -1321,15 +1376,16 @@ static int trf7970a_remove(struct spi_device *spi)
 
        mutex_lock(&trf->lock);
 
-       trf7970a_switch_rf_off(trf);
-       trf7970a_init(trf);
-
        switch (trf->state) {
        case TRF7970A_ST_WAIT_FOR_TX_FIFO:
        case TRF7970A_ST_WAIT_FOR_RX_DATA:
        case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
        case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
                trf7970a_send_err_upstream(trf, -ECANCELED);
+               /* FALLTHROUGH */
+       case TRF7970A_ST_IDLE:
+       case TRF7970A_ST_IDLE_RX_BLOCKED:
+               pm_runtime_put_sync(trf->dev);
                break;
        default:
                break;
@@ -1337,6 +1393,8 @@ static int trf7970a_remove(struct spi_device *spi)
 
        mutex_unlock(&trf->lock);
 
+       pm_runtime_disable(trf->dev);
+
        nfc_digital_unregister_device(trf->ddev);
        nfc_digital_free_device(trf->ddev);
 
@@ -1347,6 +1405,70 @@ static int trf7970a_remove(struct spi_device *spi)
        return 0;
 }
 
+#ifdef CONFIG_PM_RUNTIME
+static int trf7970a_pm_runtime_suspend(struct device *dev)
+{
+       struct spi_device *spi = container_of(dev, struct spi_device, dev);
+       struct trf7970a *trf = spi_get_drvdata(spi);
+       int ret;
+
+       dev_dbg(dev, "Runtime suspend\n");
+
+       if (trf->state != TRF7970A_ST_OFF) {
+               dev_dbg(dev, "Can't suspend - not in OFF state (%d)\n",
+                               trf->state);
+               return -EBUSY;
+       }
+
+       gpio_set_value(trf->en_gpio, 0);
+       gpio_set_value(trf->en2_gpio, 0);
+
+       ret = regulator_disable(trf->regulator);
+       if (ret)
+               dev_err(dev, "%s - Can't disable VIN: %d\n", __func__, ret);
+
+       return ret;
+}
+
+static int trf7970a_pm_runtime_resume(struct device *dev)
+{
+       struct spi_device *spi = container_of(dev, struct spi_device, dev);
+       struct trf7970a *trf = spi_get_drvdata(spi);
+       int ret;
+
+       dev_dbg(dev, "Runtime resume\n");
+
+       ret = regulator_enable(trf->regulator);
+       if (ret) {
+               dev_err(dev, "%s - Can't enable VIN: %d\n", __func__, ret);
+               return ret;
+       }
+
+       usleep_range(5000, 6000);
+
+       gpio_set_value(trf->en2_gpio, 1);
+       usleep_range(1000, 2000);
+       gpio_set_value(trf->en_gpio, 1);
+
+       usleep_range(20000, 21000);
+
+       ret = trf7970a_init(trf);
+       if (ret) {
+               dev_err(dev, "%s - Can't initialize: %d\n", __func__, ret);
+               return ret;
+       }
+
+       pm_runtime_mark_last_busy(dev);
+
+       return 0;
+}
+#endif
+
+static const struct dev_pm_ops trf7970a_pm_ops = {
+       SET_RUNTIME_PM_OPS(trf7970a_pm_runtime_suspend,
+                       trf7970a_pm_runtime_resume, NULL)
+};
+
 static const struct spi_device_id trf7970a_id_table[] = {
        { "trf7970a", TRF7970A_QUIRK_IRQ_STATUS_READ_ERRATA },
        { }
@@ -1360,6 +1482,7 @@ static struct spi_driver trf7970a_spi_driver = {
        .driver         = {
                .name   = "trf7970a",
                .owner  = THIS_MODULE,
+               .pm     = &trf7970a_pm_ops,
        },
 };