Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[linux-2.6.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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22 #include <linux/moduleparam.h>
23 #include <linux/firmware.h>
24 #include <linux/jiffies.h>
25 #include <linux/list.h>
26 #include <linux/netdevice.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_packet {
38         struct list_head                list;
39         u16                             blen;
40         u8                              buffer[0] __attribute__((aligned(4)));
41 };
42
43 struct if_spi_card {
44         struct spi_device               *spi;
45         struct lbs_private              *priv;
46         struct libertas_spi_platform_data *pdata;
47
48         /* The card ID and card revision, as reported by the hardware. */
49         u16                             card_id;
50         u8                              card_rev;
51
52         /* The last time that we initiated an SPU operation */
53         unsigned long                   prev_xfer_time;
54
55         int                             use_dummy_writes;
56         unsigned long                   spu_port_delay;
57         unsigned long                   spu_reg_delay;
58
59         /* Handles all SPI communication (except for FW load) */
60         struct workqueue_struct         *workqueue;
61         struct work_struct              packet_work;
62         struct work_struct              resume_work;
63
64         u8                              cmd_buffer[IF_SPI_CMD_BUF_SIZE];
65
66         /* A buffer of incoming packets from libertas core.
67          * Since we can't sleep in hw_host_to_card, we have to buffer
68          * them. */
69         struct list_head                cmd_packet_list;
70         struct list_head                data_packet_list;
71
72         /* Protects cmd_packet_list and data_packet_list */
73         spinlock_t                      buffer_lock;
74
75         /* True is card suspended */
76         u8                              suspended;
77 };
78
79 static void free_if_spi_card(struct if_spi_card *card)
80 {
81         struct list_head *cursor, *next;
82         struct if_spi_packet *packet;
83
84         list_for_each_safe(cursor, next, &card->cmd_packet_list) {
85                 packet = container_of(cursor, struct if_spi_packet, list);
86                 list_del(&packet->list);
87                 kfree(packet);
88         }
89         list_for_each_safe(cursor, next, &card->data_packet_list) {
90                 packet = container_of(cursor, struct if_spi_packet, list);
91                 list_del(&packet->list);
92                 kfree(packet);
93         }
94         spi_set_drvdata(card->spi, NULL);
95         kfree(card);
96 }
97
98 #define MODEL_8385      0x04
99 #define MODEL_8686      0x0b
100 #define MODEL_8688      0x10
101
102 static const struct lbs_fw_table fw_table[] = {
103         { MODEL_8385, "libertas/gspi8385_helper.bin", "libertas/gspi8385.bin" },
104         { MODEL_8385, "libertas/gspi8385_hlp.bin", "libertas/gspi8385.bin" },
105         { MODEL_8686, "libertas/gspi8686_v9_helper.bin", "libertas/gspi8686_v9.bin" },
106         { MODEL_8686, "libertas/gspi8686_hlp.bin", "libertas/gspi8686.bin" },
107         { MODEL_8688, "libertas/gspi8688_helper.bin", "libertas/gspi8688.bin" },
108         { 0, NULL, NULL }
109 };
110 MODULE_FIRMWARE("libertas/gspi8385_helper.bin");
111 MODULE_FIRMWARE("libertas/gspi8385_hlp.bin");
112 MODULE_FIRMWARE("libertas/gspi8385.bin");
113 MODULE_FIRMWARE("libertas/gspi8686_v9_helper.bin");
114 MODULE_FIRMWARE("libertas/gspi8686_v9.bin");
115 MODULE_FIRMWARE("libertas/gspi8686_hlp.bin");
116 MODULE_FIRMWARE("libertas/gspi8686.bin");
117 MODULE_FIRMWARE("libertas/gspi8688_helper.bin");
118 MODULE_FIRMWARE("libertas/gspi8688.bin");
119
120
121 /*
122  * SPI Interface Unit Routines
123  *
124  * The SPU sits between the host and the WLAN module.
125  * All communication with the firmware is through SPU transactions.
126  *
127  * First we have to put a SPU register name on the bus. Then we can
128  * either read from or write to that register.
129  *
130  */
131
132 static void spu_transaction_init(struct if_spi_card *card)
133 {
134         if (!time_after(jiffies, card->prev_xfer_time + 1)) {
135                 /* Unfortunately, the SPU requires a delay between successive
136                  * transactions. If our last transaction was more than a jiffy
137                  * ago, we have obviously already delayed enough.
138                  * If not, we have to busy-wait to be on the safe side. */
139                 ndelay(400);
140         }
141 }
142
143 static void spu_transaction_finish(struct if_spi_card *card)
144 {
145         card->prev_xfer_time = jiffies;
146 }
147
148 /*
149  * Write out a byte buffer to an SPI register,
150  * using a series of 16-bit transfers.
151  */
152 static int spu_write(struct if_spi_card *card, u16 reg, const u8 *buf, int len)
153 {
154         int err = 0;
155         __le16 reg_out = cpu_to_le16(reg | IF_SPI_WRITE_OPERATION_MASK);
156         struct spi_message m;
157         struct spi_transfer reg_trans;
158         struct spi_transfer data_trans;
159
160         spi_message_init(&m);
161         memset(&reg_trans, 0, sizeof(reg_trans));
162         memset(&data_trans, 0, sizeof(data_trans));
163
164         /* You must give an even number of bytes to the SPU, even if it
165          * doesn't care about the last one.  */
166         BUG_ON(len & 0x1);
167
168         spu_transaction_init(card);
169
170         /* write SPU register index */
171         reg_trans.tx_buf = &reg_out;
172         reg_trans.len = sizeof(reg_out);
173
174         data_trans.tx_buf = buf;
175         data_trans.len = len;
176
177         spi_message_add_tail(&reg_trans, &m);
178         spi_message_add_tail(&data_trans, &m);
179
180         err = spi_sync(card->spi, &m);
181         spu_transaction_finish(card);
182         return err;
183 }
184
185 static inline int spu_write_u16(struct if_spi_card *card, u16 reg, u16 val)
186 {
187         __le16 buff;
188
189         buff = cpu_to_le16(val);
190         return spu_write(card, reg, (u8 *)&buff, sizeof(u16));
191 }
192
193 static inline int spu_reg_is_port_reg(u16 reg)
194 {
195         switch (reg) {
196         case IF_SPI_IO_RDWRPORT_REG:
197         case IF_SPI_CMD_RDWRPORT_REG:
198         case IF_SPI_DATA_RDWRPORT_REG:
199                 return 1;
200         default:
201                 return 0;
202         }
203 }
204
205 static int spu_read(struct if_spi_card *card, u16 reg, u8 *buf, int len)
206 {
207         unsigned int delay;
208         int err = 0;
209         __le16 reg_out = cpu_to_le16(reg | IF_SPI_READ_OPERATION_MASK);
210         struct spi_message m;
211         struct spi_transfer reg_trans;
212         struct spi_transfer dummy_trans;
213         struct spi_transfer data_trans;
214
215         /*
216          * You must take an even number of bytes from the SPU, even if you
217          * don't care about the last one.
218          */
219         BUG_ON(len & 0x1);
220
221         spu_transaction_init(card);
222
223         spi_message_init(&m);
224         memset(&reg_trans, 0, sizeof(reg_trans));
225         memset(&dummy_trans, 0, sizeof(dummy_trans));
226         memset(&data_trans, 0, sizeof(data_trans));
227
228         /* write SPU register index */
229         reg_trans.tx_buf = &reg_out;
230         reg_trans.len = sizeof(reg_out);
231         spi_message_add_tail(&reg_trans, &m);
232
233         delay = spu_reg_is_port_reg(reg) ? card->spu_port_delay :
234                                                 card->spu_reg_delay;
235         if (card->use_dummy_writes) {
236                 /* Clock in dummy cycles while the SPU fills the FIFO */
237                 dummy_trans.len = delay / 8;
238                 spi_message_add_tail(&dummy_trans, &m);
239         } else {
240                 /* Busy-wait while the SPU fills the FIFO */
241                 reg_trans.delay_usecs =
242                         DIV_ROUND_UP((100 + (delay * 10)), 1000);
243         }
244
245         /* read in data */
246         data_trans.rx_buf = buf;
247         data_trans.len = len;
248         spi_message_add_tail(&data_trans, &m);
249
250         err = spi_sync(card->spi, &m);
251         spu_transaction_finish(card);
252         return err;
253 }
254
255 /* Read 16 bits from an SPI register */
256 static inline int spu_read_u16(struct if_spi_card *card, u16 reg, u16 *val)
257 {
258         __le16 buf;
259         int ret;
260
261         ret = spu_read(card, reg, (u8 *)&buf, sizeof(buf));
262         if (ret == 0)
263                 *val = le16_to_cpup(&buf);
264         return ret;
265 }
266
267 /*
268  * Read 32 bits from an SPI register.
269  * The low 16 bits are read first.
270  */
271 static int spu_read_u32(struct if_spi_card *card, u16 reg, u32 *val)
272 {
273         __le32 buf;
274         int err;
275
276         err = spu_read(card, reg, (u8 *)&buf, sizeof(buf));
277         if (!err)
278                 *val = le32_to_cpup(&buf);
279         return err;
280 }
281
282 /*
283  * Keep reading 16 bits from an SPI register until you get the correct result.
284  *
285  * If mask = 0, the correct result is any non-zero number.
286  * If mask != 0, the correct result is any number where
287  * number & target_mask == target
288  *
289  * Returns -ETIMEDOUT if a second passes without the correct result.
290  */
291 static int spu_wait_for_u16(struct if_spi_card *card, u16 reg,
292                         u16 target_mask, u16 target)
293 {
294         int err;
295         unsigned long timeout = jiffies + 5*HZ;
296         while (1) {
297                 u16 val;
298                 err = spu_read_u16(card, reg, &val);
299                 if (err)
300                         return err;
301                 if (target_mask) {
302                         if ((val & target_mask) == target)
303                                 return 0;
304                 } else {
305                         if (val)
306                                 return 0;
307                 }
308                 udelay(100);
309                 if (time_after(jiffies, timeout)) {
310                         pr_err("%s: timeout with val=%02x, target_mask=%02x, target=%02x\n",
311                                __func__, val, target_mask, target);
312                         return -ETIMEDOUT;
313                 }
314         }
315 }
316
317 /*
318  * Read 16 bits from an SPI register until you receive a specific value.
319  * Returns -ETIMEDOUT if a 4 tries pass without success.
320  */
321 static int spu_wait_for_u32(struct if_spi_card *card, u32 reg, u32 target)
322 {
323         int err, try;
324         for (try = 0; try < 4; ++try) {
325                 u32 val = 0;
326                 err = spu_read_u32(card, reg, &val);
327                 if (err)
328                         return err;
329                 if (val == target)
330                         return 0;
331                 mdelay(100);
332         }
333         return -ETIMEDOUT;
334 }
335
336 static int spu_set_interrupt_mode(struct if_spi_card *card,
337                            int suppress_host_int,
338                            int auto_int)
339 {
340         int err = 0;
341
342         /*
343          * We can suppress a host interrupt by clearing the appropriate
344          * bit in the "host interrupt status mask" register
345          */
346         if (suppress_host_int) {
347                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, 0);
348                 if (err)
349                         return err;
350         } else {
351                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG,
352                               IF_SPI_HISM_TX_DOWNLOAD_RDY |
353                               IF_SPI_HISM_RX_UPLOAD_RDY |
354                               IF_SPI_HISM_CMD_DOWNLOAD_RDY |
355                               IF_SPI_HISM_CARDEVENT |
356                               IF_SPI_HISM_CMD_UPLOAD_RDY);
357                 if (err)
358                         return err;
359         }
360
361         /*
362          * If auto-interrupts are on, the completion of certain transactions
363          * will trigger an interrupt automatically. If auto-interrupts
364          * are off, we need to set the "Card Interrupt Cause" register to
365          * trigger a card interrupt.
366          */
367         if (auto_int) {
368                 err = spu_write_u16(card, IF_SPI_HOST_INT_CTRL_REG,
369                                 IF_SPI_HICT_TX_DOWNLOAD_OVER_AUTO |
370                                 IF_SPI_HICT_RX_UPLOAD_OVER_AUTO |
371                                 IF_SPI_HICT_CMD_DOWNLOAD_OVER_AUTO |
372                                 IF_SPI_HICT_CMD_UPLOAD_OVER_AUTO);
373                 if (err)
374                         return err;
375         } else {
376                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_MASK_REG, 0);
377                 if (err)
378                         return err;
379         }
380         return err;
381 }
382
383 static int spu_get_chip_revision(struct if_spi_card *card,
384                                   u16 *card_id, u8 *card_rev)
385 {
386         int err = 0;
387         u32 dev_ctrl;
388         err = spu_read_u32(card, IF_SPI_DEVICEID_CTRL_REG, &dev_ctrl);
389         if (err)
390                 return err;
391         *card_id = IF_SPI_DEVICEID_CTRL_REG_TO_CARD_ID(dev_ctrl);
392         *card_rev = IF_SPI_DEVICEID_CTRL_REG_TO_CARD_REV(dev_ctrl);
393         return err;
394 }
395
396 static int spu_set_bus_mode(struct if_spi_card *card, u16 mode)
397 {
398         int err = 0;
399         u16 rval;
400         /* set bus mode */
401         err = spu_write_u16(card, IF_SPI_SPU_BUS_MODE_REG, mode);
402         if (err)
403                 return err;
404         /* Check that we were able to read back what we just wrote. */
405         err = spu_read_u16(card, IF_SPI_SPU_BUS_MODE_REG, &rval);
406         if (err)
407                 return err;
408         if ((rval & 0xF) != mode) {
409                 pr_err("Can't read bus mode register\n");
410                 return -EIO;
411         }
412         return 0;
413 }
414
415 static int spu_init(struct if_spi_card *card, int use_dummy_writes)
416 {
417         int err = 0;
418         u32 delay;
419
420         /*
421          * We have to start up in timed delay mode so that we can safely
422          * read the Delay Read Register.
423          */
424         card->use_dummy_writes = 0;
425         err = spu_set_bus_mode(card,
426                                 IF_SPI_BUS_MODE_SPI_CLOCK_PHASE_RISING |
427                                 IF_SPI_BUS_MODE_DELAY_METHOD_TIMED |
428                                 IF_SPI_BUS_MODE_16_BIT_ADDRESS_16_BIT_DATA);
429         if (err)
430                 return err;
431         card->spu_port_delay = 1000;
432         card->spu_reg_delay = 1000;
433         err = spu_read_u32(card, IF_SPI_DELAY_READ_REG, &delay);
434         if (err)
435                 return err;
436         card->spu_port_delay = delay & 0x0000ffff;
437         card->spu_reg_delay = (delay & 0xffff0000) >> 16;
438
439         /* If dummy clock delay mode has been requested, switch to it now */
440         if (use_dummy_writes) {
441                 card->use_dummy_writes = 1;
442                 err = spu_set_bus_mode(card,
443                                 IF_SPI_BUS_MODE_SPI_CLOCK_PHASE_RISING |
444                                 IF_SPI_BUS_MODE_DELAY_METHOD_DUMMY_CLOCK |
445                                 IF_SPI_BUS_MODE_16_BIT_ADDRESS_16_BIT_DATA);
446                 if (err)
447                         return err;
448         }
449
450         lbs_deb_spi("Initialized SPU unit. "
451                     "spu_port_delay=0x%04lx, spu_reg_delay=0x%04lx\n",
452                     card->spu_port_delay, card->spu_reg_delay);
453         return err;
454 }
455
456 /*
457  * Firmware Loading
458  */
459
460 static int if_spi_prog_helper_firmware(struct if_spi_card *card,
461                                         const struct firmware *firmware)
462 {
463         int err = 0;
464         int bytes_remaining;
465         const u8 *fw;
466         u8 temp[HELPER_FW_LOAD_CHUNK_SZ];
467
468         lbs_deb_enter(LBS_DEB_SPI);
469
470         err = spu_set_interrupt_mode(card, 1, 0);
471         if (err)
472                 goto out;
473
474         bytes_remaining = firmware->size;
475         fw = firmware->data;
476
477         /* Load helper firmware image */
478         while (bytes_remaining > 0) {
479                 /*
480                  * Scratch pad 1 should contain the number of bytes we
481                  * want to download to the firmware
482                  */
483                 err = spu_write_u16(card, IF_SPI_SCRATCH_1_REG,
484                                         HELPER_FW_LOAD_CHUNK_SZ);
485                 if (err)
486                         goto out;
487
488                 err = spu_wait_for_u16(card, IF_SPI_HOST_INT_STATUS_REG,
489                                         IF_SPI_HIST_CMD_DOWNLOAD_RDY,
490                                         IF_SPI_HIST_CMD_DOWNLOAD_RDY);
491                 if (err)
492                         goto out;
493
494                 /*
495                  * Feed the data into the command read/write port reg
496                  * in chunks of 64 bytes
497                  */
498                 memset(temp, 0, sizeof(temp));
499                 memcpy(temp, fw,
500                        min(bytes_remaining, HELPER_FW_LOAD_CHUNK_SZ));
501                 mdelay(10);
502                 err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG,
503                                         temp, HELPER_FW_LOAD_CHUNK_SZ);
504                 if (err)
505                         goto out;
506
507                 /* Interrupt the boot code */
508                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0);
509                 if (err)
510                         goto out;
511                 err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG,
512                                        IF_SPI_CIC_CMD_DOWNLOAD_OVER);
513                 if (err)
514                         goto out;
515                 bytes_remaining -= HELPER_FW_LOAD_CHUNK_SZ;
516                 fw += HELPER_FW_LOAD_CHUNK_SZ;
517         }
518
519         /*
520          * Once the helper / single stage firmware download is complete,
521          * write 0 to scratch pad 1 and interrupt the
522          * bootloader. This completes the helper download.
523          */
524         err = spu_write_u16(card, IF_SPI_SCRATCH_1_REG, FIRMWARE_DNLD_OK);
525         if (err)
526                 goto out;
527         err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0);
528         if (err)
529                 goto out;
530         err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG,
531                                 IF_SPI_CIC_CMD_DOWNLOAD_OVER);
532                 goto out;
533
534         lbs_deb_spi("waiting for helper to boot...\n");
535
536 out:
537         if (err)
538                 pr_err("failed to load helper firmware (err=%d)\n", err);
539         lbs_deb_leave_args(LBS_DEB_SPI, "err %d", err);
540         return err;
541 }
542
543 /*
544  * Returns the length of the next packet the firmware expects us to send.
545  * Sets crc_err if the previous transfer had a CRC error.
546  */
547 static int if_spi_prog_main_firmware_check_len(struct if_spi_card *card,
548                                                 int *crc_err)
549 {
550         u16 len;
551         int err = 0;
552
553         /*
554          * wait until the host interrupt status register indicates
555          * that we are ready to download
556          */
557         err = spu_wait_for_u16(card, IF_SPI_HOST_INT_STATUS_REG,
558                                 IF_SPI_HIST_CMD_DOWNLOAD_RDY,
559                                 IF_SPI_HIST_CMD_DOWNLOAD_RDY);
560         if (err) {
561                 pr_err("timed out waiting for host_int_status\n");
562                 return err;
563         }
564
565         /* Ask the device how many bytes of firmware it wants. */
566         err = spu_read_u16(card, IF_SPI_SCRATCH_1_REG, &len);
567         if (err)
568                 return err;
569
570         if (len > IF_SPI_CMD_BUF_SIZE) {
571                 pr_err("firmware load device requested a larger transfer than we are prepared to handle (len = %d)\n",
572                        len);
573                 return -EIO;
574         }
575         if (len & 0x1) {
576                 lbs_deb_spi("%s: crc error\n", __func__);
577                 len &= ~0x1;
578                 *crc_err = 1;
579         } else
580                 *crc_err = 0;
581
582         return len;
583 }
584
585 static int if_spi_prog_main_firmware(struct if_spi_card *card,
586                                         const struct firmware *firmware)
587 {
588         struct lbs_private *priv = card->priv;
589         int len, prev_len;
590         int bytes, crc_err = 0, err = 0;
591         const u8 *fw;
592         u16 num_crc_errs;
593
594         lbs_deb_enter(LBS_DEB_SPI);
595
596         err = spu_set_interrupt_mode(card, 1, 0);
597         if (err)
598                 goto out;
599
600         err = spu_wait_for_u16(card, IF_SPI_SCRATCH_1_REG, 0, 0);
601         if (err) {
602                 netdev_err(priv->dev,
603                            "%s: timed out waiting for initial scratch reg = 0\n",
604                            __func__);
605                 goto out;
606         }
607
608         num_crc_errs = 0;
609         prev_len = 0;
610         bytes = firmware->size;
611         fw = firmware->data;
612         while ((len = if_spi_prog_main_firmware_check_len(card, &crc_err))) {
613                 if (len < 0) {
614                         err = len;
615                         goto out;
616                 }
617                 if (bytes < 0) {
618                         /*
619                          * If there are no more bytes left, we would normally
620                          * expect to have terminated with len = 0
621                          */
622                         netdev_err(priv->dev,
623                                    "Firmware load wants more bytes than we have to offer.\n");
624                         break;
625                 }
626                 if (crc_err) {
627                         /* Previous transfer failed. */
628                         if (++num_crc_errs > MAX_MAIN_FW_LOAD_CRC_ERR) {
629                                 pr_err("Too many CRC errors encountered in firmware load.\n");
630                                 err = -EIO;
631                                 goto out;
632                         }
633                 } else {
634                         /* Previous transfer succeeded. Advance counters. */
635                         bytes -= prev_len;
636                         fw += prev_len;
637                 }
638                 if (bytes < len) {
639                         memset(card->cmd_buffer, 0, len);
640                         memcpy(card->cmd_buffer, fw, bytes);
641                 } else
642                         memcpy(card->cmd_buffer, fw, len);
643
644                 err = spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG, 0);
645                 if (err)
646                         goto out;
647                 err = spu_write(card, IF_SPI_CMD_RDWRPORT_REG,
648                                 card->cmd_buffer, len);
649                 if (err)
650                         goto out;
651                 err = spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG ,
652                                         IF_SPI_CIC_CMD_DOWNLOAD_OVER);
653                 if (err)
654                         goto out;
655                 prev_len = len;
656         }
657         if (bytes > prev_len) {
658                 pr_err("firmware load wants fewer bytes than we have to offer\n");
659         }
660
661         /* Confirm firmware download */
662         err = spu_wait_for_u32(card, IF_SPI_SCRATCH_4_REG,
663                                         SUCCESSFUL_FW_DOWNLOAD_MAGIC);
664         if (err) {
665                 pr_err("failed to confirm the firmware download\n");
666                 goto out;
667         }
668
669 out:
670         if (err)
671                 pr_err("failed to load firmware (err=%d)\n", err);
672         lbs_deb_leave_args(LBS_DEB_SPI, "err %d", err);
673         return err;
674 }
675
676 /*
677  * SPI Transfer Thread
678  *
679  * The SPI worker handles all SPI transfers, so there is no need for a lock.
680  */
681
682 /* Move a command from the card to the host */
683 static int if_spi_c2h_cmd(struct if_spi_card *card)
684 {
685         struct lbs_private *priv = card->priv;
686         unsigned long flags;
687         int err = 0;
688         u16 len;
689         u8 i;
690
691         /*
692          * We need a buffer big enough to handle whatever people send to
693          * hw_host_to_card
694          */
695         BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE < LBS_CMD_BUFFER_SIZE);
696         BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE < LBS_UPLD_SIZE);
697
698         /*
699          * It's just annoying if the buffer size isn't a multiple of 4, because
700          * then we might have len < IF_SPI_CMD_BUF_SIZE but
701          * ALIGN(len, 4) > IF_SPI_CMD_BUF_SIZE
702          */
703         BUILD_BUG_ON(IF_SPI_CMD_BUF_SIZE % 4 != 0);
704
705         lbs_deb_enter(LBS_DEB_SPI);
706
707         /* How many bytes are there to read? */
708         err = spu_read_u16(card, IF_SPI_SCRATCH_2_REG, &len);
709         if (err)
710                 goto out;
711         if (!len) {
712                 netdev_err(priv->dev, "%s: error: card has no data for host\n",
713                            __func__);
714                 err = -EINVAL;
715                 goto out;
716         } else if (len > IF_SPI_CMD_BUF_SIZE) {
717                 netdev_err(priv->dev,
718                            "%s: error: response packet too large: %d bytes, but maximum is %d\n",
719                            __func__, len, IF_SPI_CMD_BUF_SIZE);
720                 err = -EINVAL;
721                 goto out;
722         }
723
724         /* Read the data from the WLAN module into our command buffer */
725         err = spu_read(card, IF_SPI_CMD_RDWRPORT_REG,
726                                 card->cmd_buffer, ALIGN(len, 4));
727         if (err)
728                 goto out;
729
730         spin_lock_irqsave(&priv->driver_lock, flags);
731         i = (priv->resp_idx == 0) ? 1 : 0;
732         BUG_ON(priv->resp_len[i]);
733         priv->resp_len[i] = len;
734         memcpy(priv->resp_buf[i], card->cmd_buffer, len);
735         lbs_notify_command_response(priv, i);
736         spin_unlock_irqrestore(&priv->driver_lock, flags);
737
738 out:
739         if (err)
740                 netdev_err(priv->dev, "%s: err=%d\n", __func__, err);
741         lbs_deb_leave(LBS_DEB_SPI);
742         return err;
743 }
744
745 /* Move data from the card to the host */
746 static int if_spi_c2h_data(struct if_spi_card *card)
747 {
748         struct lbs_private *priv = card->priv;
749         struct sk_buff *skb;
750         char *data;
751         u16 len;
752         int err = 0;
753
754         lbs_deb_enter(LBS_DEB_SPI);
755
756         /* How many bytes are there to read? */
757         err = spu_read_u16(card, IF_SPI_SCRATCH_1_REG, &len);
758         if (err)
759                 goto out;
760         if (!len) {
761                 netdev_err(priv->dev, "%s: error: card has no data for host\n",
762                            __func__);
763                 err = -EINVAL;
764                 goto out;
765         } else if (len > MRVDRV_ETH_RX_PACKET_BUFFER_SIZE) {
766                 netdev_err(priv->dev,
767                            "%s: error: card has %d bytes of data, but our maximum skb size is %zu\n",
768                            __func__, len, MRVDRV_ETH_RX_PACKET_BUFFER_SIZE);
769                 err = -EINVAL;
770                 goto out;
771         }
772
773         /* TODO: should we allocate a smaller skb if we have less data? */
774         skb = dev_alloc_skb(MRVDRV_ETH_RX_PACKET_BUFFER_SIZE);
775         if (!skb) {
776                 err = -ENOBUFS;
777                 goto out;
778         }
779         skb_reserve(skb, IPFIELD_ALIGN_OFFSET);
780         data = skb_put(skb, len);
781
782         /* Read the data from the WLAN module into our skb... */
783         err = spu_read(card, IF_SPI_DATA_RDWRPORT_REG, data, ALIGN(len, 4));
784         if (err)
785                 goto free_skb;
786
787         /* pass the SKB to libertas */
788         err = lbs_process_rxed_packet(card->priv, skb);
789         if (err)
790                 goto free_skb;
791
792         /* success */
793         goto out;
794
795 free_skb:
796         dev_kfree_skb(skb);
797 out:
798         if (err)
799                 netdev_err(priv->dev, "%s: err=%d\n", __func__, err);
800         lbs_deb_leave(LBS_DEB_SPI);
801         return err;
802 }
803
804 /* Move data or a command from the host to the card. */
805 static void if_spi_h2c(struct if_spi_card *card,
806                         struct if_spi_packet *packet, int type)
807 {
808         struct lbs_private *priv = card->priv;
809         int err = 0;
810         u16 int_type, port_reg;
811
812         switch (type) {
813         case MVMS_DAT:
814                 int_type = IF_SPI_CIC_TX_DOWNLOAD_OVER;
815                 port_reg = IF_SPI_DATA_RDWRPORT_REG;
816                 break;
817         case MVMS_CMD:
818                 int_type = IF_SPI_CIC_CMD_DOWNLOAD_OVER;
819                 port_reg = IF_SPI_CMD_RDWRPORT_REG;
820                 break;
821         default:
822                 netdev_err(priv->dev, "can't transfer buffer of type %d\n",
823                            type);
824                 err = -EINVAL;
825                 goto out;
826         }
827
828         /* Write the data to the card */
829         err = spu_write(card, port_reg, packet->buffer, packet->blen);
830         if (err)
831                 goto out;
832
833 out:
834         kfree(packet);
835
836         if (err)
837                 netdev_err(priv->dev, "%s: error %d\n", __func__, err);
838 }
839
840 /* Inform the host about a card event */
841 static void if_spi_e2h(struct if_spi_card *card)
842 {
843         int err = 0;
844         u32 cause;
845         struct lbs_private *priv = card->priv;
846
847         err = spu_read_u32(card, IF_SPI_SCRATCH_3_REG, &cause);
848         if (err)
849                 goto out;
850
851         /* re-enable the card event interrupt */
852         spu_write_u16(card, IF_SPI_HOST_INT_STATUS_REG,
853                         ~IF_SPI_HICU_CARD_EVENT);
854
855         /* generate a card interrupt */
856         spu_write_u16(card, IF_SPI_CARD_INT_CAUSE_REG, IF_SPI_CIC_HOST_EVENT);
857
858         lbs_queue_event(priv, cause & 0xff);
859 out:
860         if (err)
861                 netdev_err(priv->dev, "%s: error %d\n", __func__, err);
862 }
863
864 static void if_spi_host_to_card_worker(struct work_struct *work)
865 {
866         int err;
867         struct if_spi_card *card;
868         u16 hiStatus;
869         unsigned long flags;
870         struct if_spi_packet *packet;
871         struct lbs_private *priv;
872
873         card = container_of(work, struct if_spi_card, packet_work);
874         priv = card->priv;
875
876         lbs_deb_enter(LBS_DEB_SPI);
877
878         /*
879          * Read the host interrupt status register to see what we
880          * can do.
881          */
882         err = spu_read_u16(card, IF_SPI_HOST_INT_STATUS_REG,
883                                 &hiStatus);
884         if (err) {
885                 netdev_err(priv->dev, "I/O error\n");
886                 goto err;
887         }
888
889         if (hiStatus & IF_SPI_HIST_CMD_UPLOAD_RDY) {
890                 err = if_spi_c2h_cmd(card);
891                 if (err)
892                         goto err;
893         }
894         if (hiStatus & IF_SPI_HIST_RX_UPLOAD_RDY) {
895                 err = if_spi_c2h_data(card);
896                 if (err)
897                         goto err;
898         }
899
900         /*
901          * workaround: in PS mode, the card does not set the Command
902          * Download Ready bit, but it sets TX Download Ready.
903          */
904         if (hiStatus & IF_SPI_HIST_CMD_DOWNLOAD_RDY ||
905            (card->priv->psstate != PS_STATE_FULL_POWER &&
906             (hiStatus & IF_SPI_HIST_TX_DOWNLOAD_RDY))) {
907                 /*
908                  * This means two things. First of all,
909                  * if there was a previous command sent, the card has
910                  * successfully received it.
911                  * Secondly, it is now ready to download another
912                  * command.
913                  */
914                 lbs_host_to_card_done(card->priv);
915
916                 /* Do we have any command packets from the host to send? */
917                 packet = NULL;
918                 spin_lock_irqsave(&card->buffer_lock, flags);
919                 if (!list_empty(&card->cmd_packet_list)) {
920                         packet = (struct if_spi_packet *)(card->
921                                         cmd_packet_list.next);
922                         list_del(&packet->list);
923                 }
924                 spin_unlock_irqrestore(&card->buffer_lock, flags);
925
926                 if (packet)
927                         if_spi_h2c(card, packet, MVMS_CMD);
928         }
929         if (hiStatus & IF_SPI_HIST_TX_DOWNLOAD_RDY) {
930                 /* Do we have any data packets from the host to send? */
931                 packet = NULL;
932                 spin_lock_irqsave(&card->buffer_lock, flags);
933                 if (!list_empty(&card->data_packet_list)) {
934                         packet = (struct if_spi_packet *)(card->
935                                         data_packet_list.next);
936                         list_del(&packet->list);
937                 }
938                 spin_unlock_irqrestore(&card->buffer_lock, flags);
939
940                 if (packet)
941                         if_spi_h2c(card, packet, MVMS_DAT);
942         }
943         if (hiStatus & IF_SPI_HIST_CARD_EVENT)
944                 if_spi_e2h(card);
945
946 err:
947         if (err)
948                 netdev_err(priv->dev, "%s: got error %d\n", __func__, err);
949
950         lbs_deb_leave(LBS_DEB_SPI);
951 }
952
953 /*
954  * Host to Card
955  *
956  * Called from Libertas to transfer some data to the WLAN device
957  * We can't sleep here.
958  */
959 static int if_spi_host_to_card(struct lbs_private *priv,
960                                 u8 type, u8 *buf, u16 nb)
961 {
962         int err = 0;
963         unsigned long flags;
964         struct if_spi_card *card = priv->card;
965         struct if_spi_packet *packet;
966         u16 blen;
967
968         lbs_deb_enter_args(LBS_DEB_SPI, "type %d, bytes %d", type, nb);
969
970         if (nb == 0) {
971                 netdev_err(priv->dev, "%s: invalid size requested: %d\n",
972                            __func__, nb);
973                 err = -EINVAL;
974                 goto out;
975         }
976         blen = ALIGN(nb, 4);
977         packet = kzalloc(sizeof(struct if_spi_packet) + blen, GFP_ATOMIC);
978         if (!packet) {
979                 err = -ENOMEM;
980                 goto out;
981         }
982         packet->blen = blen;
983         memcpy(packet->buffer, buf, nb);
984         memset(packet->buffer + nb, 0, blen - nb);
985
986         switch (type) {
987         case MVMS_CMD:
988                 priv->dnld_sent = DNLD_CMD_SENT;
989                 spin_lock_irqsave(&card->buffer_lock, flags);
990                 list_add_tail(&packet->list, &card->cmd_packet_list);
991                 spin_unlock_irqrestore(&card->buffer_lock, flags);
992                 break;
993         case MVMS_DAT:
994                 priv->dnld_sent = DNLD_DATA_SENT;
995                 spin_lock_irqsave(&card->buffer_lock, flags);
996                 list_add_tail(&packet->list, &card->data_packet_list);
997                 spin_unlock_irqrestore(&card->buffer_lock, flags);
998                 break;
999         default:
1000                 netdev_err(priv->dev, "can't transfer buffer of type %d\n",
1001                            type);
1002                 err = -EINVAL;
1003                 break;
1004         }
1005
1006         /* Queue spi xfer work */
1007         queue_work(card->workqueue, &card->packet_work);
1008 out:
1009         lbs_deb_leave_args(LBS_DEB_SPI, "err=%d", err);
1010         return err;
1011 }
1012
1013 /*
1014  * Host Interrupts
1015  *
1016  * Service incoming interrupts from the WLAN device. We can't sleep here, so
1017  * don't try to talk on the SPI bus, just queue the SPI xfer work.
1018  */
1019 static irqreturn_t if_spi_host_interrupt(int irq, void *dev_id)
1020 {
1021         struct if_spi_card *card = dev_id;
1022
1023         queue_work(card->workqueue, &card->packet_work);
1024
1025         return IRQ_HANDLED;
1026 }
1027
1028 /*
1029  * SPI callbacks
1030  */
1031
1032 static int if_spi_init_card(struct if_spi_card *card)
1033 {
1034         struct lbs_private *priv = card->priv;
1035         int err, i;
1036         u32 scratch;
1037         const struct firmware *helper = NULL;
1038         const struct firmware *mainfw = NULL;
1039
1040         lbs_deb_enter(LBS_DEB_SPI);
1041
1042         err = spu_init(card, card->pdata->use_dummy_writes);
1043         if (err)
1044                 goto out;
1045         err = spu_get_chip_revision(card, &card->card_id, &card->card_rev);
1046         if (err)
1047                 goto out;
1048
1049         err = spu_read_u32(card, IF_SPI_SCRATCH_4_REG, &scratch);
1050         if (err)
1051                 goto out;
1052         if (scratch == SUCCESSFUL_FW_DOWNLOAD_MAGIC)
1053                 lbs_deb_spi("Firmware is already loaded for "
1054                             "Marvell WLAN 802.11 adapter\n");
1055         else {
1056                 /* Check if we support this card */
1057                 for (i = 0; i < ARRAY_SIZE(fw_table); i++) {
1058                         if (card->card_id == fw_table[i].model)
1059                                 break;
1060                 }
1061                 if (i == ARRAY_SIZE(fw_table)) {
1062                         netdev_err(priv->dev, "Unsupported chip_id: 0x%02x\n",
1063                                    card->card_id);
1064                         err = -ENODEV;
1065                         goto out;
1066                 }
1067
1068                 err = lbs_get_firmware(&card->spi->dev, NULL, NULL,
1069                                         card->card_id, &fw_table[0], &helper,
1070                                         &mainfw);
1071                 if (err) {
1072                         netdev_err(priv->dev, "failed to find firmware (%d)\n",
1073                                    err);
1074                         goto out;
1075                 }
1076
1077                 lbs_deb_spi("Initializing FW for Marvell WLAN 802.11 adapter "
1078                                 "(chip_id = 0x%04x, chip_rev = 0x%02x) "
1079                                 "attached to SPI bus_num %d, chip_select %d. "
1080                                 "spi->max_speed_hz=%d\n",
1081                                 card->card_id, card->card_rev,
1082                                 card->spi->master->bus_num,
1083                                 card->spi->chip_select,
1084                                 card->spi->max_speed_hz);
1085                 err = if_spi_prog_helper_firmware(card, helper);
1086                 if (err)
1087                         goto out;
1088                 err = if_spi_prog_main_firmware(card, mainfw);
1089                 if (err)
1090                         goto out;
1091                 lbs_deb_spi("loaded FW for Marvell WLAN 802.11 adapter\n");
1092         }
1093
1094         err = spu_set_interrupt_mode(card, 0, 1);
1095         if (err)
1096                 goto out;
1097
1098 out:
1099         if (helper)
1100                 release_firmware(helper);
1101         if (mainfw)
1102                 release_firmware(mainfw);
1103
1104         lbs_deb_leave_args(LBS_DEB_SPI, "err %d\n", err);
1105
1106         return err;
1107 }
1108
1109 static void if_spi_resume_worker(struct work_struct *work)
1110 {
1111         struct if_spi_card *card;
1112
1113         card = container_of(work, struct if_spi_card, resume_work);
1114
1115         if (card->suspended) {
1116                 if (card->pdata->setup)
1117                         card->pdata->setup(card->spi);
1118
1119                 /* Init card ... */
1120                 if_spi_init_card(card);
1121
1122                 enable_irq(card->spi->irq);
1123
1124                 /* And resume it ... */
1125                 lbs_resume(card->priv);
1126
1127                 card->suspended = 0;
1128         }
1129 }
1130
1131 static int __devinit if_spi_probe(struct spi_device *spi)
1132 {
1133         struct if_spi_card *card;
1134         struct lbs_private *priv = NULL;
1135         struct libertas_spi_platform_data *pdata = spi->dev.platform_data;
1136         int err = 0;
1137
1138         lbs_deb_enter(LBS_DEB_SPI);
1139
1140         if (!pdata) {
1141                 err = -EINVAL;
1142                 goto out;
1143         }
1144
1145         if (pdata->setup) {
1146                 err = pdata->setup(spi);
1147                 if (err)
1148                         goto out;
1149         }
1150
1151         /* Allocate card structure to represent this specific device */
1152         card = kzalloc(sizeof(struct if_spi_card), GFP_KERNEL);
1153         if (!card) {
1154                 err = -ENOMEM;
1155                 goto teardown;
1156         }
1157         spi_set_drvdata(spi, card);
1158         card->pdata = pdata;
1159         card->spi = spi;
1160         card->prev_xfer_time = jiffies;
1161
1162         INIT_LIST_HEAD(&card->cmd_packet_list);
1163         INIT_LIST_HEAD(&card->data_packet_list);
1164         spin_lock_init(&card->buffer_lock);
1165
1166         /* Initialize the SPI Interface Unit */
1167
1168         /* Firmware load */
1169         err = if_spi_init_card(card);
1170         if (err)
1171                 goto free_card;
1172
1173         /*
1174          * Register our card with libertas.
1175          * This will call alloc_etherdev.
1176          */
1177         priv = lbs_add_card(card, &spi->dev);
1178         if (!priv) {
1179                 err = -ENOMEM;
1180                 goto free_card;
1181         }
1182         card->priv = priv;
1183         priv->setup_fw_on_resume = 1;
1184         priv->card = card;
1185         priv->hw_host_to_card = if_spi_host_to_card;
1186         priv->enter_deep_sleep = NULL;
1187         priv->exit_deep_sleep = NULL;
1188         priv->reset_deep_sleep_wakeup = NULL;
1189         priv->fw_ready = 1;
1190
1191         /* Initialize interrupt handling stuff. */
1192         card->workqueue = create_workqueue("libertas_spi");
1193         INIT_WORK(&card->packet_work, if_spi_host_to_card_worker);
1194         INIT_WORK(&card->resume_work, if_spi_resume_worker);
1195
1196         err = request_irq(spi->irq, if_spi_host_interrupt,
1197                         IRQF_TRIGGER_FALLING, "libertas_spi", card);
1198         if (err) {
1199                 pr_err("can't get host irq line-- request_irq failed\n");
1200                 goto terminate_workqueue;
1201         }
1202
1203         /*
1204          * Start the card.
1205          * This will call register_netdev, and we'll start
1206          * getting interrupts...
1207          */
1208         err = lbs_start_card(priv);
1209         if (err)
1210                 goto release_irq;
1211
1212         lbs_deb_spi("Finished initializing WLAN module.\n");
1213
1214         /* successful exit */
1215         goto out;
1216
1217 release_irq:
1218         free_irq(spi->irq, card);
1219 terminate_workqueue:
1220         flush_workqueue(card->workqueue);
1221         destroy_workqueue(card->workqueue);
1222         lbs_remove_card(priv); /* will call free_netdev */
1223 free_card:
1224         free_if_spi_card(card);
1225 teardown:
1226         if (pdata->teardown)
1227                 pdata->teardown(spi);
1228 out:
1229         lbs_deb_leave_args(LBS_DEB_SPI, "err %d\n", err);
1230         return err;
1231 }
1232
1233 static int __devexit libertas_spi_remove(struct spi_device *spi)
1234 {
1235         struct if_spi_card *card = spi_get_drvdata(spi);
1236         struct lbs_private *priv = card->priv;
1237
1238         lbs_deb_spi("libertas_spi_remove\n");
1239         lbs_deb_enter(LBS_DEB_SPI);
1240
1241         cancel_work_sync(&card->resume_work);
1242
1243         lbs_stop_card(priv);
1244         lbs_remove_card(priv); /* will call free_netdev */
1245
1246         free_irq(spi->irq, card);
1247         flush_workqueue(card->workqueue);
1248         destroy_workqueue(card->workqueue);
1249         if (card->pdata->teardown)
1250                 card->pdata->teardown(spi);
1251         free_if_spi_card(card);
1252         lbs_deb_leave(LBS_DEB_SPI);
1253         return 0;
1254 }
1255
1256 static int if_spi_suspend(struct device *dev)
1257 {
1258         struct spi_device *spi = to_spi_device(dev);
1259         struct if_spi_card *card = spi_get_drvdata(spi);
1260
1261         if (!card->suspended) {
1262                 lbs_suspend(card->priv);
1263                 flush_workqueue(card->workqueue);
1264                 disable_irq(spi->irq);
1265
1266                 if (card->pdata->teardown)
1267                         card->pdata->teardown(spi);
1268                 card->suspended = 1;
1269         }
1270
1271         return 0;
1272 }
1273
1274 static int if_spi_resume(struct device *dev)
1275 {
1276         struct spi_device *spi = to_spi_device(dev);
1277         struct if_spi_card *card = spi_get_drvdata(spi);
1278
1279         /* Schedule delayed work */
1280         schedule_work(&card->resume_work);
1281
1282         return 0;
1283 }
1284
1285 static const struct dev_pm_ops if_spi_pm_ops = {
1286         .suspend        = if_spi_suspend,
1287         .resume         = if_spi_resume,
1288 };
1289
1290 static struct spi_driver libertas_spi_driver = {
1291         .probe  = if_spi_probe,
1292         .remove = __devexit_p(libertas_spi_remove),
1293         .driver = {
1294                 .name   = "libertas_spi",
1295                 .bus    = &spi_bus_type,
1296                 .owner  = THIS_MODULE,
1297                 .pm     = &if_spi_pm_ops,
1298         },
1299 };
1300
1301 /*
1302  * Module functions
1303  */
1304
1305 static int __init if_spi_init_module(void)
1306 {
1307         int ret = 0;
1308         lbs_deb_enter(LBS_DEB_SPI);
1309         printk(KERN_INFO "libertas_spi: Libertas SPI driver\n");
1310         ret = spi_register_driver(&libertas_spi_driver);
1311         lbs_deb_leave(LBS_DEB_SPI);
1312         return ret;
1313 }
1314
1315 static void __exit if_spi_exit_module(void)
1316 {
1317         lbs_deb_enter(LBS_DEB_SPI);
1318         spi_unregister_driver(&libertas_spi_driver);
1319         lbs_deb_leave(LBS_DEB_SPI);
1320 }
1321
1322 module_init(if_spi_init_module);
1323 module_exit(if_spi_exit_module);
1324
1325 MODULE_DESCRIPTION("Libertas SPI WLAN Driver");
1326 MODULE_AUTHOR("Andrey Yurovsky <andrey@cozybit.com>, "
1327               "Colin McCabe <colin@cozybit.com>");
1328 MODULE_LICENSE("GPL");
1329 MODULE_ALIAS("spi:libertas_spi");