Merge branch 'x86-tsc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[cascardo/linux.git] / drivers / net / wireless / libertas / if_spi.c
1 /*
2  *      linux/drivers/net/wireless/libertas/if_spi.c
3  *
4  *      Driver for Marvell SPI WLAN cards.
5  *
6  *      Copyright 2008 Analog Devices Inc.
7  *
8  *      Authors:
9  *      Andrey Yurovsky <andrey@cozybit.com>
10  *      Colin McCabe <colin@cozybit.com>
11  *
12  *      Inspired by if_sdio.c, Copyright 2007-2008 Pierre Ossman
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  */
19
20 #include <linux/moduleparam.h>
21 #include <linux/firmware.h>
22 #include <linux/jiffies.h>
23 #include <linux/kthread.h>
24 #include <linux/list.h>
25 #include <linux/netdevice.h>
26 #include <linux/semaphore.h>
27 #include <linux/slab.h>
28 #include <linux/spi/libertas_spi.h>
29 #include <linux/spi/spi.h>
30
31 #include "host.h"
32 #include "decl.h"
33 #include "defs.h"
34 #include "dev.h"
35 #include "if_spi.h"
36
37 struct if_spi_card {
38         struct spi_device               *spi;
39         struct lbs_private              *priv;
40         struct libertas_spi_platform_data *pdata;
41
42         /* The card ID and card revision, as reported by the hardware. */
43         u16                             card_id;
44         u8                              card_rev;
45
46         /* The last time that we initiated an SPU operation */
47         unsigned long                   prev_xfer_time;
48
49         int                             use_dummy_writes;
50         unsigned long                   spu_port_delay;
51         unsigned long                   spu_reg_delay;
52
53         /* Handles all SPI communication (except for FW load) */
54         struct task_struct              *spi_thread;
55         int                             run_thread;
56
57         /* Used to wake up the spi_thread */
58         struct semaphore                spi_ready;
59         struct semaphore                spi_thread_terminated;
60
61         u8                              cmd_buffer[IF_SPI_CMD_BUF_SIZE];
62 };
63
64 static void free_if_spi_card(struct if_spi_card *card)
65 {
66         spi_set_drvdata(card->spi, NULL);
67         kfree(card);
68 }
69
70 #define MODEL_8385      0x04
71 #define MODEL_8686      0x0b
72 #define MODEL_8688      0x10
73
74 static const struct lbs_fw_table fw_table[] = {
75         { MODEL_8385, "libertas/gspi8385_helper.bin", "libertas/gspi8385.bin" },
76         { MODEL_8385, "libertas/gspi8385_hlp.bin", "libertas/gspi8385.bin" },
77         { MODEL_8686, "libertas/gspi8686_v9_helper.bin", "libertas/gspi8686_v9.bin" },
78         { MODEL_8686, "libertas/gspi8686_hlp.bin", "libertas/gspi8686.bin" },
79         { MODEL_8688, "libertas/gspi8688_helper.bin", "libertas/gspi8688.bin" },
80         { 0, NULL, NULL }
81 };
82 MODULE_FIRMWARE("libertas/gspi8385_helper.bin");
83 MODULE_FIRMWARE("libertas/gspi8385_hlp.bin");
84 MODULE_FIRMWARE("libertas/gspi8385.bin");
85 MODULE_FIRMWARE("libertas/gspi8686_v9_helper.bin");
86 MODULE_FIRMWARE("libertas/gspi8686_v9.bin");
87 MODULE_FIRMWARE("libertas/gspi8686_hlp.bin");
88 MODULE_FIRMWARE("libertas/gspi8686.bin");
89 MODULE_FIRMWARE("libertas/gspi8688_helper.bin");
90 MODULE_FIRMWARE("libertas/gspi8688.bin");
91
92
93 /*
94  * SPI Interface Unit Routines
95  *
96  * The SPU sits between the host and the WLAN module.
97  * All communication with the firmware is through SPU transactions.
98  *
99  * First we have to put a SPU register name on the bus. Then we can
100  * either read from or write to that register.
101  *
102  */
103
104 static void spu_transaction_init(struct if_spi_card *card)
105 {
106         if (!time_after(jiffies, card->prev_xfer_time + 1)) {
107                 /* Unfortunately, the SPU requires a delay between successive
108                  * transactions. If our last transaction was more than a jiffy
109                  * ago, we have obviously already delayed enough.
110                  * If not, we have to busy-wait to be on the safe side. */
111                 ndelay(400);
112         }
113 }
114
115 static void spu_transaction_finish(struct if_spi_card *card)
116 {
117         card->prev_xfer_time = jiffies;
118 }
119
120 /* Write out a byte buffer to an SPI register,
121  * using a series of 16-bit transfers. */
122 static int spu_write(struct if_spi_card *card, u16 reg, const u8 *buf, int len)
123 {
124         int err = 0;
125         __le16 reg_out = cpu_to_le16(reg | IF_SPI_WRITE_OPERATION_MASK);
126         struct spi_message m;
127         struct spi_transfer reg_trans;
128         struct spi_transfer data_trans;
129
130         spi_message_init(&m);
131         memset(&reg_trans, 0, sizeof(reg_trans));
132         memset(&data_trans, 0, sizeof(data_trans));
133
134         /* You must give an even number of bytes to the SPU, even if it
135          * doesn't care about the last one.  */
136         BUG_ON(len & 0x1);
137
138         spu_transaction_init(card);
139
140         /* write SPU register index */
141         reg_trans.tx_buf = &reg_out;
142         reg_trans.len = sizeof(reg_out);
143
144         data_trans.tx_buf = buf;
145         data_trans.len = len;
146
147         spi_message_add_tail(&reg_trans, &m);
148         spi_message_add_tail(&data_trans, &m);
149
150         err = spi_sync(card->spi, &m);
151         spu_transaction_finish(card);
152         return err;
153 }
154
155 static inline int spu_write_u16(struct if_spi_card *card, u16 reg, u16 val)
156 {
157         __le16 buff;
158
159         buff = cpu_to_le16(val);
160         return spu_write(card, reg, (u8 *)&buff, sizeof(u16));
161 }
162
163 static inline int spu_reg_is_port_reg(u16 reg)
164 {
165         switch (reg) {
166         case IF_SPI_IO_RDWRPORT_REG:
167         case IF_SPI_CMD_RDWRPORT_REG:
168         case IF_SPI_DATA_RDWRPORT_REG:
169                 return 1;
170         default:
171                 return 0;
172         }
173 }
174
175 static int spu_read(struct if_spi_card *card, u16 reg, u8 *buf, int len)
176 {
177         unsigned int delay;
178         int err = 0;
179         __le16 reg_out = cpu_to_le16(reg | IF_SPI_READ_OPERATION_MASK);
180         struct spi_message m;
181         struct spi_transfer reg_trans;
182         struct spi_transfer dummy_trans;
183         struct spi_transfer data_trans;
184
185         /* You must take an even number of bytes from the SPU, even if you
186          * don't care about the last one.  */
187         BUG_ON(len & 0x1);
188
189         spu_transaction_init(card);
190
191         spi_message_init(&m);
192         memset(&reg_trans, 0, sizeof(reg_trans));
193         memset(&dummy_trans, 0, sizeof(dummy_trans));
194         memset(&data_trans, 0, sizeof(data_trans));
195
196         /* write SPU register index */
197         reg_trans.tx_buf = &reg_out;
198         reg_trans.len = sizeof(reg_out);
199         spi_message_add_tail(&reg_trans, &m);
200
201         delay = spu_reg_is_port_reg(reg) ? card->spu_port_delay :
202                                                 card->spu_reg_delay;
203         if (card->use_dummy_writes) {
204                 /* Clock in dummy cycles while the SPU fills the FIFO */
205                 dummy_trans.len = delay / 8;
206                 spi_message_add_tail(&dummy_trans, &m);
207         } else {
208                 /* Busy-wait while the SPU fills the FIFO */
209                 reg_trans.delay_usecs =
210                         DIV_ROUND_UP((100 + (delay * 10)), 1000);
211         }
212
213         /* read in data */
214         data_trans.rx_buf = buf;
215         data_trans.len = len;
216         spi_message_add_tail(&data_trans, &m);
217
218         err = spi_sync(card->spi, &m);
219         spu_transaction_finish(card);
220         return err;
221 }
222
223 /* Read 16 bits from an SPI register */
224 static inline int spu_read_u16(struct if_spi_card *card, u16 reg, u16 *val)
225 {
226         __le16 buf;
227         int ret;
228
229         ret = spu_read(card, reg, (u8 *)&buf, sizeof(buf));
230         if (ret == 0)
231                 *val = le16_to_cpup(&buf);
232         return ret;
233 }
234
235 /* Read 32 bits from an SPI register.
236  * The low 16 bits are read first. */
237 static int spu_read_u32(struct if_spi_card *card, u16 reg, u32 *val)
238 {
239         __le32 buf;
240         int err;
241
242         err = spu_read(card, reg, (u8 *)&buf, sizeof(buf));
243         if (!err)
244                 *val = le32_to_cpup(&buf);
245         return err;
246 }
247
248 /* Keep reading 16 bits from an SPI register until you get the correct result.
249  *
250  * If mask = 0, the correct result is any non-zero number.
251  * If mask != 0, the correct result is any number where
252  * number & target_mask == target
253  *
254  * Returns -ETIMEDOUT if a second passes without the correct result. */
255 static int spu_wait_for_u16(struct if_spi_card *card, u16 reg,
256                         u16 target_mask, u16 target)
257 {
258         int err;
259         unsigned long timeout = jiffies + 5*HZ;
260         while (1) {
261                 u16 val;
262                 err = spu_read_u16(card, reg, &val);
263                 if (err)
264                         return err;
265                 if (target_mask) {
266                         if ((val & target_mask) == target)
267                                 return 0;
268                 } else {
269                         if (val)
270                                 return 0;
271                 }
272                 udelay(100);
273                 if (time_after(jiffies, timeout)) {
274                         lbs_pr_err("%s: timeout with val=%02x, "
275                                "target_mask=%02x, target=%02x\n",
276                                __func__, val, target_mask, target);
277                         return -ETIMEDOUT;
278                 }
279         }
280 }
281
282 /* Read 16 bits from an SPI register until you receive a specific value.
283  * Returns -ETIMEDOUT if a 4 tries pass without success. */
284 static int spu_wait_for_u32(struct if_spi_card *card, u32 reg, u32 target)
285 {
286         int err, try;
287         for (try = 0; try < 4; ++try) {
288                 u32 val = 0;
289                 err = spu_read_u32(card, reg, &val);
290                 if (err)
291                         return err;
292                 if (val == target)
293                         return 0;
294                 mdelay(100);
295         }
296         return -ETIMEDOUT;
297 }
298
299 static int spu_set_interrupt_mode(struct if_spi_card *card,
300                            int suppress_host_int,
301                            int auto_int)
302 {
303         int err = 0;
304
305         /* We can suppress a host interrupt by clearing the appropriate
306          * bit in the "host interrupt status mask" register */
307         if (suppress_host_int) {
308                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, 0);
309                 if (err)
310                         return err;
311         } else {
312                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG,
313                               IF_SPI_HISM_TX_DOWNLOAD_RDY |
314                               IF_SPI_HISM_RX_UPLOAD_RDY |
315                               IF_SPI_HISM_CMD_DOWNLOAD_RDY |
316                               IF_SPI_HISM_CARDEVENT |
317                               IF_SPI_HISM_CMD_UPLOAD_RDY);
318                 if (err)
319                         return err;
320         }
321
322         /* If auto-interrupts are on, the completion of certain transactions
323          * will trigger an interrupt automatically. If auto-interrupts
324          * are off, we need to set the "Card Interrupt Cause" register to
325          * trigger a card interrupt. */
326         if (auto_int) {
327                 err = spu_write_u16(card, IF_SPI_HOST_INT_CTRL_REG,
328                                 IF_SPI_HICT_TX_DOWNLOAD_OVER_AUTO |
329                                 IF_SPI_HICT_RX_UPLOAD_OVER_AUTO |
330                                 IF_SPI_HICT_CMD_DOWNLOAD_OVER_AUTO |
331                                 IF_SPI_HICT_CMD_UPLOAD_OVER_AUTO);
332                 if (err)
333                         return err;
334         } else {
335                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, 0);
336                 if (err)
337                         return err;
338         }
339         return err;
340 }
341
342 static int spu_get_chip_revision(struct if_spi_card *card,
343                                   u16 *card_id, u8 *card_rev)
344 {
345         int err = 0;
346         u32 dev_ctrl;
347         err = spu_read_u32(card, IF_SPI_DEVICEID_CTRL_REG, &dev_ctrl);
348         if (err)
349                 return err;
350         *card_id = IF_SPI_DEVICEID_CTRL_REG_TO_CARD_ID(dev_ctrl);
351         *card_rev = IF_SPI_DEVICEID_CTRL_REG_TO_CARD_REV(dev_ctrl);
352         return err;
353 }
354
355 static int spu_set_bus_mode(struct if_spi_card *card, u16 mode)
356 {
357         int err = 0;
358         u16 rval;
359         /* set bus mode */
360         err = spu_write_u16(card, IF_SPI_SPU_BUS_MODE_REG, mode);
361         if (err)
362                 return err;
363         /* Check that we were able to read back what we just wrote. */
364         err = spu_read_u16(card, IF_SPI_SPU_BUS_MODE_REG, &rval);
365         if (err)
366                 return err;
367         if ((rval & 0xF) != mode) {
368                 lbs_pr_err("Can't read bus mode register.\n");
369                 return -EIO;
370         }
371         return 0;
372 }
373
374 static int spu_init(struct if_spi_card *card, int use_dummy_writes)
375 {
376         int err = 0;
377         u32 delay;
378
379         /* We have to start up in timed delay mode so that we can safely
380          * read the Delay Read Register. */
381         card->use_dummy_writes = 0;
382         err = spu_set_bus_mode(card,
383                                 IF_SPI_BUS_MODE_SPI_CLOCK_PHASE_RISING |
384                                 IF_SPI_BUS_MODE_DELAY_METHOD_TIMED |
385                                 IF_SPI_BUS_MODE_16_BIT_ADDRESS_16_BIT_DATA);
386         if (err)
387                 return err;
388         card->spu_port_delay = 1000;
389         card->spu_reg_delay = 1000;
390         err = spu_read_u32(card, IF_SPI_DELAY_READ_REG, &delay);
391         if (err)
392                 return err;
393         card->spu_port_delay = delay & 0x0000ffff;
394         card->spu_reg_delay = (delay & 0xffff0000) >> 16;
395
396         /* If dummy clock delay mode has been requested, switch to it now */
397         if (use_dummy_writes) {
398                 card->use_dummy_writes = 1;
399                 err = spu_set_bus_mode(card,
400                                 IF_SPI_BUS_MODE_SPI_CLOCK_PHASE_RISING |
401                                 IF_SPI_BUS_MODE_DELAY_METHOD_DUMMY_CLOCK |
402                                 IF_SPI_BUS_MODE_16_BIT_ADDRESS_16_BIT_DATA);
403                 if (err)
404                         return err;
405         }
406
407         lbs_deb_spi("Initialized SPU unit. "
408                     "spu_port_delay=0x%04lx, spu_reg_delay=0x%04lx\n",
409                     card->spu_port_delay, card->spu_reg_delay);
410         return err;
411 }
412
413 /*
414  * Firmware Loading
415  */
416
417 static int if_spi_prog_helper_firmware(struct if_spi_card *card,
418                                         const struct firmware *firmware)
419 {
420         int err = 0;
421         int bytes_remaining;
422         const u8 *fw;
423         u8 temp[HELPER_FW_LOAD_CHUNK_SZ];
424
425         lbs_deb_enter(LBS_DEB_SPI);
426
427         err = spu_set_interrupt_mode(card, 1, 0);
428         if (err)
429                 goto out;
430
431         bytes_remaining = firmware->size;
432         fw = firmware->data;
433
434         /* Load helper firmware image */
435         while (bytes_remaining > 0) {
436                 /* Scratch pad 1 should contain the number of bytes we
437                  * want to download to the firmware */
438                 err = spu_write_u16(card, IF_SPI_SCRATCH_1_REG,
439                                         HELPER_FW_LOAD_CHUNK_SZ);
440                 if (err)
441                         goto out;
442
443                 err = spu_wait_for_u16(card, IF_SPI_HOST_INT_STATUS_REG,
444                                         IF_SPI_HIST_CMD_DOWNLOAD_RDY,
445                                         IF_SPI_HIST_CMD_DOWNLOAD_RDY);
446                 if (err)
447                         goto out;
448
449                 /* Feed the data into the command read/write port reg
450                  * in chunks of 64 bytes */
451                 memset(temp, 0, sizeof(temp));
452                 memcpy(temp, fw,
453                        min(bytes_remaining, HELPER_FW_LOAD_CHUNK_SZ));
454                 mdelay(10);
455                 err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG,
456                                         temp, HELPER_FW_LOAD_CHUNK_SZ);
457                 if (err)
458                         goto out;
459
460                 /* Interrupt the boot code */
461                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0);
462                 if (err)
463                         goto out;
464                 err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG,
465                                        IF_SPI_CIC_CMD_DOWNLOAD_OVER);
466                 if (err)
467                         goto out;
468                 bytes_remaining -= HELPER_FW_LOAD_CHUNK_SZ;
469                 fw += HELPER_FW_LOAD_CHUNK_SZ;
470         }
471
472         /* Once the helper / single stage firmware download is complete,
473          * write 0 to scratch pad 1 and interrupt the
474          * bootloader. This completes the helper download. */
475         err = spu_write_u16(card, IF_SPI_SCRATCH_1_REG, FIRMWARE_DNLD_OK);
476         if (err)
477                 goto out;
478         err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0);
479         if (err)
480                 goto out;
481         err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG,
482                                 IF_SPI_CIC_CMD_DOWNLOAD_OVER);
483                 goto out;
484
485         lbs_deb_spi("waiting for helper to boot...\n");
486
487 out:
488         if (err)
489                 lbs_pr_err("failed to load helper firmware (err=%d)\n", err);
490         lbs_deb_leave_args(LBS_DEB_SPI, "err %d", err);
491         return err;
492 }
493
494 /* Returns the length of the next packet the firmware expects us to send
495  * Sets crc_err if the previous transfer had a CRC error. */
496 static int if_spi_prog_main_firmware_check_len(struct if_spi_card *card,
497                                                 int *crc_err)
498 {
499         u16 len;
500         int err = 0;
501
502         /* wait until the host interrupt status register indicates
503          * that we are ready to download */
504         err = spu_wait_for_u16(card, IF_SPI_HOST_INT_STATUS_REG,
505                                 IF_SPI_HIST_CMD_DOWNLOAD_RDY,
506                                 IF_SPI_HIST_CMD_DOWNLOAD_RDY);
507         if (err) {
508                 lbs_pr_err("timed out waiting for host_int_status\n");
509                 return err;
510         }
511
512         /* Ask the device how many bytes of firmware it wants. */
513         err = spu_read_u16(card, IF_SPI_SCRATCH_1_REG, &len);
514         if (err)
515                 return err;
516
517         if (len > IF_SPI_CMD_BUF_SIZE) {
518                 lbs_pr_err("firmware load device requested a larger "
519                            "tranfer than we are prepared to "
520                            "handle. (len = %d)\n", len);
521                 return -EIO;
522         }
523         if (len & 0x1) {
524                 lbs_deb_spi("%s: crc error\n", __func__);
525                 len &= ~0x1;
526                 *crc_err = 1;
527         } else
528                 *crc_err = 0;
529
530         return len;
531 }
532
533 static int if_spi_prog_main_firmware(struct if_spi_card *card,
534                                         const struct firmware *firmware)
535 {
536         int len, prev_len;
537         int bytes, crc_err = 0, err = 0;
538         const u8 *fw;
539         u16 num_crc_errs;
540
541         lbs_deb_enter(LBS_DEB_SPI);
542
543         err = spu_set_interrupt_mode(card, 1, 0);
544         if (err)
545                 goto out;
546
547         err = spu_wait_for_u16(card, IF_SPI_SCRATCH_1_REG, 0, 0);
548         if (err) {
549                 lbs_pr_err("%s: timed out waiting for initial "
550                            "scratch reg = 0\n", __func__);
551                 goto out;
552         }
553
554         num_crc_errs = 0;
555         prev_len = 0;
556         bytes = firmware->size;
557         fw = firmware->data;
558         while ((len = if_spi_prog_main_firmware_check_len(card, &crc_err))) {
559                 if (len < 0) {
560                         err = len;
561                         goto out;
562                 }
563                 if (bytes < 0) {
564                         /* If there are no more bytes left, we would normally
565                          * expect to have terminated with len = 0 */
566                         lbs_pr_err("Firmware load wants more bytes "
567                                    "than we have to offer.\n");
568                         break;
569                 }
570                 if (crc_err) {
571                         /* Previous transfer failed. */
572                         if (++num_crc_errs > MAX_MAIN_FW_LOAD_CRC_ERR) {
573                                 lbs_pr_err("Too many CRC errors encountered "
574                                            "in firmware load.\n");
575                                 err = -EIO;
576                                 goto out;
577                         }
578                 } else {
579                         /* Previous transfer succeeded. Advance counters. */
580                         bytes -= prev_len;
581                         fw += prev_len;
582                 }
583                 if (bytes < len) {
584                         memset(card->cmd_buffer, 0, len);
585                         memcpy(card->cmd_buffer, fw, bytes);
586                 } else
587                         memcpy(card->cmd_buffer, fw, len);
588
589                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0);
590                 if (err)
591                         goto out;
592                 err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG,
593                                 card->cmd_buffer, len);
594                 if (err)
595                         goto out;
596                 err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG ,
597                                         IF_SPI_CIC_CMD_DOWNLOAD_OVER);
598                 if (err)
599                         goto out;
600                 prev_len = len;
601         }
602         if (bytes > prev_len) {
603                 lbs_pr_err("firmware load wants fewer bytes than "
604                            "we have to offer.\n");
605         }
606
607         /* Confirm firmware download */
608         err = spu_wait_for_u32(card, IF_SPI_SCRATCH_4_REG,
609                                         SUCCESSFUL_FW_DOWNLOAD_MAGIC);
610         if (err) {
611                 lbs_pr_err("failed to confirm the firmware download\n");
612                 goto out;
613         }
614
615 out:
616         if (err)
617                 lbs_pr_err("failed to load firmware (err=%d)\n", err);
618         lbs_deb_leave_args(LBS_DEB_SPI, "err %d", err);
619         return err;
620 }
621
622 /*
623  * SPI Transfer Thread
624  *
625  * The SPI thread handles all SPI transfers, so there is no need for a lock.
626  */
627
628 /* Move a command from the card to the host */
629 static int if_spi_c2h_cmd(struct if_spi_card *card)
630 {
631         struct lbs_private *priv = card->priv;
632         unsigned long flags;
633         int err = 0;
634         u16 len;
635         u8 i;
636
637         /* We need a buffer big enough to handle whatever people send to
638          * hw_host_to_card */
639         BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE < LBS_CMD_BUFFER_SIZE);
640         BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE < LBS_UPLD_SIZE);
641
642         /* It's just annoying if the buffer size isn't a multiple of 4, because
643          * then we might have len <  IF_SPI_CMD_BUF_SIZE but
644          * ALIGN(len, 4) > IF_SPI_CMD_BUF_SIZE */
645         BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE % 4 != 0);
646
647         lbs_deb_enter(LBS_DEB_SPI);
648
649         /* How many bytes are there to read? */
650         err = spu_read_u16(card, IF_SPI_SCRATCH_2_REG, &len);
651         if (err)
652                 goto out;
653         if (!len) {
654                 lbs_pr_err("%s: error: card has no data for host\n",
655                            __func__);
656                 err = -EINVAL;
657                 goto out;
658         } else if (len > IF_SPI_CMD_BUF_SIZE) {
659                 lbs_pr_err("%s: error: response packet too large: "
660                            "%d bytes, but maximum is %d\n",
661                            __func__, len, IF_SPI_CMD_BUF_SIZE);
662                 err = -EINVAL;
663                 goto out;
664         }
665
666         /* Read the data from the WLAN module into our command buffer */
667         err = spu_read(card, IF_SPI_CMD_RDWRPORT_REG,
668                                 card->cmd_buffer, ALIGN(len, 4));
669         if (err)
670                 goto out;
671
672         spin_lock_irqsave(&priv->driver_lock, flags);
673         i = (priv->resp_idx == 0) ? 1 : 0;
674         BUG_ON(priv->resp_len[i]);
675         priv->resp_len[i] = len;
676         memcpy(priv->resp_buf[i], card->cmd_buffer, len);
677         lbs_notify_command_response(priv, i);
678         spin_unlock_irqrestore(&priv->driver_lock, flags);
679
680 out:
681         if (err)
682                 lbs_pr_err("%s: err=%d\n", __func__, err);
683         lbs_deb_leave(LBS_DEB_SPI);
684         return err;
685 }
686
687 /* Move data from the card to the host */
688 static int if_spi_c2h_data(struct if_spi_card *card)
689 {
690         struct sk_buff *skb;
691         char *data;
692         u16 len;
693         int err = 0;
694
695         lbs_deb_enter(LBS_DEB_SPI);
696
697         /* How many bytes are there to read? */
698         err = spu_read_u16(card, IF_SPI_SCRATCH_1_REG, &len);
699         if (err)
700                 goto out;
701         if (!len) {
702                 lbs_pr_err("%s: error: card has no data for host\n",
703                            __func__);
704                 err = -EINVAL;
705                 goto out;
706         } else if (len > MRVDRV_ETH_RX_PACKET_BUFFER_SIZE) {
707                 lbs_pr_err("%s: error: card has %d bytes of data, but "
708                            "our maximum skb size is %zu\n",
709                            __func__, len, MRVDRV_ETH_RX_PACKET_BUFFER_SIZE);
710                 err = -EINVAL;
711                 goto out;
712         }
713
714         /* TODO: should we allocate a smaller skb if we have less data? */
715         skb = dev_alloc_skb(MRVDRV_ETH_RX_PACKET_BUFFER_SIZE);
716         if (!skb) {
717                 err = -ENOBUFS;
718                 goto out;
719         }
720         skb_reserve(skb, IPFIELD_ALIGN_OFFSET);
721         data = skb_put(skb, len);
722
723         /* Read the data from the WLAN module into our skb... */
724         err = spu_read(card, IF_SPI_DATA_RDWRPORT_REG, data, ALIGN(len, 4));
725         if (err)
726                 goto free_skb;
727
728         /* pass the SKB to libertas */
729         err = lbs_process_rxed_packet(card->priv, skb);
730         if (err)
731                 goto free_skb;
732
733         /* success */
734         goto out;
735
736 free_skb:
737         dev_kfree_skb(skb);
738 out:
739         if (err)
740                 lbs_pr_err("%s: err=%d\n", __func__, err);
741         lbs_deb_leave(LBS_DEB_SPI);
742         return err;
743 }
744
745 /* Inform the host about a card event */
746 static void if_spi_e2h(struct if_spi_card *card)
747 {
748         int err = 0;
749         u32 cause;
750         struct lbs_private *priv = card->priv;
751
752         err = spu_read_u32(card, IF_SPI_SCRATCH_3_REG, &cause);
753         if (err)
754                 goto out;
755
756         /* re-enable the card event interrupt */
757         spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG,
758                         ~IF_SPI_HICU_CARD_EVENT);
759
760         /* generate a card interrupt */
761         spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG, IF_SPI_CIC_HOST_EVENT);
762
763         lbs_queue_event(priv, cause & 0xff);
764 out:
765         if (err)
766                 lbs_pr_err("%s: error %d\n", __func__, err);
767 }
768
769 static int lbs_spi_thread(void *data)
770 {
771         int err;
772         struct if_spi_card *card = data;
773         u16 hiStatus;
774
775         while (1) {
776                 /* Wait to be woken up by one of two things.  First, our ISR
777                  * could tell us that something happened on the WLAN.
778                  * Secondly, libertas could call hw_host_to_card with more
779                  * data, which we might be able to send.
780                  */
781                 do {
782                         err = down_interruptible(&card->spi_ready);
783                         if (!card->run_thread) {
784                                 up(&card->spi_thread_terminated);
785                                 do_exit(0);
786                         }
787                 } while (err == EINTR);
788
789                 /* Read the host interrupt status register to see what we
790                  * can do. */
791                 err = spu_read_u16(card, IF_SPI_HOST_INT_STATUS_REG,
792                                         &hiStatus);
793                 if (err) {
794                         lbs_pr_err("I/O error\n");
795                         goto err;
796                 }
797
798                 if (hiStatus & IF_SPI_HIST_CMD_UPLOAD_RDY) {
799                         err = if_spi_c2h_cmd(card);
800                         if (err)
801                                 goto err;
802                 }
803                 if (hiStatus & IF_SPI_HIST_RX_UPLOAD_RDY) {
804                         err = if_spi_c2h_data(card);
805                         if (err)
806                                 goto err;
807                 }
808
809                 /* workaround: in PS mode, the card does not set the Command
810                  * Download Ready bit, but it sets TX Download Ready. */
811                 if (hiStatus & IF_SPI_HIST_CMD_DOWNLOAD_RDY ||
812                    (card->priv->psstate != PS_STATE_FULL_POWER &&
813                     (hiStatus & IF_SPI_HIST_TX_DOWNLOAD_RDY))) {
814                         lbs_host_to_card_done(card->priv);
815                 }
816
817                 if (hiStatus & IF_SPI_HIST_CARD_EVENT)
818                         if_spi_e2h(card);
819
820 err:
821                 if (err)
822                         lbs_pr_err("%s: got error %d\n", __func__, err);
823         }
824 }
825
826 /* Block until lbs_spi_thread thread has terminated */
827 static void if_spi_terminate_spi_thread(struct if_spi_card *card)
828 {
829         /* It would be nice to use kthread_stop here, but that function
830          * can't wake threads waiting for a semaphore. */
831         card->run_thread = 0;
832         up(&card->spi_ready);
833         down(&card->spi_thread_terminated);
834 }
835
836 /*
837  * Host to Card
838  *
839  * Called from Libertas to transfer some data to the WLAN device
840  * We can't sleep here. */
841 static int if_spi_host_to_card(struct lbs_private *priv,
842                                 u8 type, u8 *buf, u16 nb)
843 {
844         int err = 0;
845         struct if_spi_card *card = priv->card;
846
847         lbs_deb_enter_args(LBS_DEB_SPI, "type %d, bytes %d", type, nb);
848
849         nb = ALIGN(nb, 4);
850
851         switch (type) {
852         case MVMS_CMD:
853                 err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG, buf, nb);
854                 break;
855         case MVMS_DAT:
856                 err = spu_write(card, IF_SPI_DATA_RDWRPORT_REG, buf, nb);
857                 break;
858         default:
859                 lbs_pr_err("can't transfer buffer of type %d", type);
860                 err = -EINVAL;
861                 break;
862         }
863
864         lbs_deb_leave_args(LBS_DEB_SPI, "err=%d", err);
865         return err;
866 }
867
868 /*
869  * Host Interrupts
870  *
871  * Service incoming interrupts from the WLAN device. We can't sleep here, so
872  * don't try to talk on the SPI bus, just wake up the SPI thread.
873  */
874 static irqreturn_t if_spi_host_interrupt(int irq, void *dev_id)
875 {
876         struct if_spi_card *card = dev_id;
877
878         up(&card->spi_ready);
879         return IRQ_HANDLED;
880 }
881
882 /*
883  * SPI callbacks
884  */
885
886 static int __devinit if_spi_probe(struct spi_device *spi)
887 {
888         struct if_spi_card *card;
889         struct lbs_private *priv = NULL;
890         struct libertas_spi_platform_data *pdata = spi->dev.platform_data;
891         int err = 0, i;
892         u32 scratch;
893         struct sched_param param = { .sched_priority = 1 };
894         const struct firmware *helper = NULL;
895         const struct firmware *mainfw = NULL;
896
897         lbs_deb_enter(LBS_DEB_SPI);
898
899         if (!pdata) {
900                 err = -EINVAL;
901                 goto out;
902         }
903
904         if (pdata->setup) {
905                 err = pdata->setup(spi);
906                 if (err)
907                         goto out;
908         }
909
910         /* Allocate card structure to represent this specific device */
911         card = kzalloc(sizeof(struct if_spi_card), GFP_KERNEL);
912         if (!card) {
913                 err = -ENOMEM;
914                 goto out;
915         }
916         spi_set_drvdata(spi, card);
917         card->pdata = pdata;
918         card->spi = spi;
919         card->prev_xfer_time = jiffies;
920
921         sema_init(&card->spi_ready, 0);
922         sema_init(&card->spi_thread_terminated, 0);
923
924         /* Initialize the SPI Interface Unit */
925         err = spu_init(card, pdata->use_dummy_writes);
926         if (err)
927                 goto free_card;
928         err = spu_get_chip_revision(card, &card->card_id, &card->card_rev);
929         if (err)
930                 goto free_card;
931
932         /* Firmware load */
933         err = spu_read_u32(card, IF_SPI_SCRATCH_4_REG, &scratch);
934         if (err)
935                 goto free_card;
936         if (scratch == SUCCESSFUL_FW_DOWNLOAD_MAGIC)
937                 lbs_deb_spi("Firmware is already loaded for "
938                             "Marvell WLAN 802.11 adapter\n");
939         else {
940                 /* Check if we support this card */
941                 for (i = 0; i < ARRAY_SIZE(fw_table); i++) {
942                         if (card->card_id == fw_table[i].model)
943                                 break;
944                 }
945                 if (i == ARRAY_SIZE(fw_table)) {
946                         lbs_pr_err("Unsupported chip_id: 0x%02x\n",
947                                         card->card_id);
948                         err = -ENODEV;
949                         goto free_card;
950                 }
951
952                 err = lbs_get_firmware(&card->spi->dev, NULL, NULL,
953                                         card->card_id, &fw_table[0], &helper,
954                                         &mainfw);
955                 if (err) {
956                         lbs_pr_err("failed to find firmware (%d)\n", err);
957                         goto free_card;
958                 }
959
960                 lbs_deb_spi("Initializing FW for Marvell WLAN 802.11 adapter "
961                                 "(chip_id = 0x%04x, chip_rev = 0x%02x) "
962                                 "attached to SPI bus_num %d, chip_select %d. "
963                                 "spi->max_speed_hz=%d\n",
964                                 card->card_id, card->card_rev,
965                                 spi->master->bus_num, spi->chip_select,
966                                 spi->max_speed_hz);
967                 err = if_spi_prog_helper_firmware(card, helper);
968                 if (err)
969                         goto free_card;
970                 err = if_spi_prog_main_firmware(card, mainfw);
971                 if (err)
972                         goto free_card;
973                 lbs_deb_spi("loaded FW for Marvell WLAN 802.11 adapter\n");
974         }
975
976         err = spu_set_interrupt_mode(card, 0, 1);
977         if (err)
978                 goto free_card;
979
980         /* Register our card with libertas.
981          * This will call alloc_etherdev */
982         priv = lbs_add_card(card, &spi->dev);
983         if (!priv) {
984                 err = -ENOMEM;
985                 goto free_card;
986         }
987         card->priv = priv;
988         priv->card = card;
989         priv->hw_host_to_card = if_spi_host_to_card;
990         priv->enter_deep_sleep = NULL;
991         priv->exit_deep_sleep = NULL;
992         priv->reset_deep_sleep_wakeup = NULL;
993         priv->fw_ready = 1;
994
995         /* Initialize interrupt handling stuff. */
996         card->run_thread = 1;
997         card->spi_thread = kthread_run(lbs_spi_thread, card, "lbs_spi_thread");
998         if (IS_ERR(card->spi_thread)) {
999                 card->run_thread = 0;
1000                 err = PTR_ERR(card->spi_thread);
1001                 lbs_pr_err("error creating SPI thread: err=%d\n", err);
1002                 goto remove_card;
1003         }
1004         if (sched_setscheduler(card->spi_thread, SCHED_FIFO, &param))
1005                 lbs_pr_err("Error setting scheduler, using default.\n");
1006
1007         err = request_irq(spi->irq, if_spi_host_interrupt,
1008                         IRQF_TRIGGER_FALLING, "libertas_spi", card);
1009         if (err) {
1010                 lbs_pr_err("can't get host irq line-- request_irq failed\n");
1011                 goto terminate_thread;
1012         }
1013
1014         /* poke the IRQ handler so that we don't miss the first interrupt */
1015         up(&card->spi_ready);
1016
1017         /* Start the card.
1018          * This will call register_netdev, and we'll start
1019          * getting interrupts... */
1020         err = lbs_start_card(priv);
1021         if (err)
1022                 goto release_irq;
1023
1024         lbs_deb_spi("Finished initializing WLAN module.\n");
1025
1026         /* successful exit */
1027         goto out;
1028
1029 release_irq:
1030         free_irq(spi->irq, card);
1031 terminate_thread:
1032         if_spi_terminate_spi_thread(card);
1033 remove_card:
1034         lbs_remove_card(priv); /* will call free_netdev */
1035 free_card:
1036         free_if_spi_card(card);
1037 out:
1038         if (helper)
1039                 release_firmware(helper);
1040         if (mainfw)
1041                 release_firmware(mainfw);
1042
1043         lbs_deb_leave_args(LBS_DEB_SPI, "err %d\n", err);
1044         return err;
1045 }
1046
1047 static int __devexit libertas_spi_remove(struct spi_device *spi)
1048 {
1049         struct if_spi_card *card = spi_get_drvdata(spi);
1050         struct lbs_private *priv = card->priv;
1051
1052         lbs_deb_spi("libertas_spi_remove\n");
1053         lbs_deb_enter(LBS_DEB_SPI);
1054
1055         lbs_stop_card(priv);
1056         lbs_remove_card(priv); /* will call free_netdev */
1057
1058         free_irq(spi->irq, card);
1059         if_spi_terminate_spi_thread(card);
1060         if (card->pdata->teardown)
1061                 card->pdata->teardown(spi);
1062         free_if_spi_card(card);
1063         lbs_deb_leave(LBS_DEB_SPI);
1064         return 0;
1065 }
1066
1067 static struct spi_driver libertas_spi_driver = {
1068         .probe  = if_spi_probe,
1069         .remove = __devexit_p(libertas_spi_remove),
1070         .driver = {
1071                 .name   = "libertas_spi",
1072                 .bus    = &spi_bus_type,
1073                 .owner  = THIS_MODULE,
1074         },
1075 };
1076
1077 /*
1078  * Module functions
1079  */
1080
1081 static int __init if_spi_init_module(void)
1082 {
1083         int ret = 0;
1084         lbs_deb_enter(LBS_DEB_SPI);
1085         printk(KERN_INFO "libertas_spi: Libertas SPI driver\n");
1086         ret = spi_register_driver(&libertas_spi_driver);
1087         lbs_deb_leave(LBS_DEB_SPI);
1088         return ret;
1089 }
1090
1091 static void __exit if_spi_exit_module(void)
1092 {
1093         lbs_deb_enter(LBS_DEB_SPI);
1094         spi_unregister_driver(&libertas_spi_driver);
1095         lbs_deb_leave(LBS_DEB_SPI);
1096 }
1097
1098 module_init(if_spi_init_module);
1099 module_exit(if_spi_exit_module);
1100
1101 MODULE_DESCRIPTION("Libertas SPI WLAN Driver");
1102 MODULE_AUTHOR("Andrey Yurovsky <andrey@cozybit.com>, "
1103               "Colin McCabe <colin@cozybit.com>");
1104 MODULE_LICENSE("GPL");
1105 MODULE_ALIAS("spi:libertas_spi");