?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
thp: clear_copy_huge_page
[linux/fpc-iii.git] / drivers / spi / spi_bfin5xx.c
blob3f223511127b56c9a6800743991aea342e5e2e92
1 /*
2 * Blackfin On-Chip SPI Driver
3 *
4 * Copyright 2004-2010 Analog Devices Inc.
5 *
6 * Enter bugs at http://blackfin.uclinux.org/
7 *
8 * Licensed under the GPL-2 or later.
9 */
10
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/slab.h>
16 #include <linux/io.h>
17 #include <linux/ioport.h>
18 #include <linux/irq.h>
19 #include <linux/errno.h>
20 #include <linux/interrupt.h>
21 #include <linux/platform_device.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/spi/spi.h>
24 #include <linux/workqueue.h>
25
26 #include <asm/dma.h>
27 #include <asm/portmux.h>
28 #include <asm/bfin5xx_spi.h>
29 #include <asm/cacheflush.h>
30
31 #define DRV_NAME "bfin-spi"
32 #define DRV_AUTHOR "Bryan Wu, Luke Yang"
33 #define DRV_DESC "Blackfin on-chip SPI Controller Driver"
34 #define DRV_VERSION "1.0"
35
36 MODULE_AUTHOR(DRV_AUTHOR);
37 MODULE_DESCRIPTION(DRV_DESC);
38 MODULE_LICENSE("GPL");
39
40 #define START_STATE ((void *)0)
41 #define RUNNING_STATE ((void *)1)
42 #define DONE_STATE ((void *)2)
43 #define ERROR_STATE ((void *)-1)
44
45 struct bfin_spi_master_data;
46
47 struct bfin_spi_transfer_ops {
48 void (*write) (struct bfin_spi_master_data *);
49 void (*read) (struct bfin_spi_master_data *);
50 void (*duplex) (struct bfin_spi_master_data *);
51 };
52
53 struct bfin_spi_master_data {
54 /* Driver model hookup */
55 struct platform_device *pdev;
56
57 /* SPI framework hookup */
58 struct spi_master *master;
59
60 /* Regs base of SPI controller */
61 void __iomem *regs_base;
62
63 /* Pin request list */
64 u16 *pin_req;
65
66 /* BFIN hookup */
67 struct bfin5xx_spi_master *master_info;
68
69 /* Driver message queue */
70 struct workqueue_struct *workqueue;
71 struct work_struct pump_messages;
72 spinlock_t lock;
73 struct list_head queue;
74 int busy;
75 bool running;
76
77 /* Message Transfer pump */
78 struct tasklet_struct pump_transfers;
79
80 /* Current message transfer state info */
81 struct spi_message *cur_msg;
82 struct spi_transfer *cur_transfer;
83 struct bfin_spi_slave_data *cur_chip;
84 size_t len_in_bytes;
85 size_t len;
86 void *tx;
87 void *tx_end;
88 void *rx;
89 void *rx_end;
90
91 /* DMA stuffs */
92 int dma_channel;
93 int dma_mapped;
94 int dma_requested;
95 dma_addr_t rx_dma;
96 dma_addr_t tx_dma;
97
98 int irq_requested;
99 int spi_irq;
100
101 size_t rx_map_len;
102 size_t tx_map_len;
103 u8 n_bytes;
104 u16 ctrl_reg;
105 u16 flag_reg;
106
107 int cs_change;
108 const struct bfin_spi_transfer_ops *ops;
109 };
110
111 struct bfin_spi_slave_data {
112 u16 ctl_reg;
113 u16 baud;
114 u16 flag;
115
116 u8 chip_select_num;
117 u8 enable_dma;
118 u16 cs_chg_udelay; /* Some devices require > 255usec delay */
119 u32 cs_gpio;
120 u16 idle_tx_val;
121 u8 pio_interrupt; /* use spi data irq */
122 const struct bfin_spi_transfer_ops *ops;
123 };
124
125 #define DEFINE_SPI_REG(reg, off) \
126 static inline u16 read_##reg(struct bfin_spi_master_data *drv_data) \
127 { return bfin_read16(drv_data->regs_base + off); } \
128 static inline void write_##reg(struct bfin_spi_master_data *drv_data, u16 v) \
129 { bfin_write16(drv_data->regs_base + off, v); }
130
131 DEFINE_SPI_REG(CTRL, 0x00)
132 DEFINE_SPI_REG(FLAG, 0x04)
133 DEFINE_SPI_REG(STAT, 0x08)
134 DEFINE_SPI_REG(TDBR, 0x0C)
135 DEFINE_SPI_REG(RDBR, 0x10)
136 DEFINE_SPI_REG(BAUD, 0x14)
137 DEFINE_SPI_REG(SHAW, 0x18)
138
139 static void bfin_spi_enable(struct bfin_spi_master_data *drv_data)
140 {
141 u16 cr;
142
143 cr = read_CTRL(drv_data);
144 write_CTRL(drv_data, (cr | BIT_CTL_ENABLE));
145 }
146
147 static void bfin_spi_disable(struct bfin_spi_master_data *drv_data)
148 {
149 u16 cr;
150
151 cr = read_CTRL(drv_data);
152 write_CTRL(drv_data, (cr & (~BIT_CTL_ENABLE)));
153 }
154
155 /* Caculate the SPI_BAUD register value based on input HZ */
156 static u16 hz_to_spi_baud(u32 speed_hz)
157 {
158 u_long sclk = get_sclk();
159 u16 spi_baud = (sclk / (2 * speed_hz));
160
161 if ((sclk % (2 * speed_hz)) > 0)
162 spi_baud++;
163
164 if (spi_baud < MIN_SPI_BAUD_VAL)
165 spi_baud = MIN_SPI_BAUD_VAL;
166
167 return spi_baud;
168 }
169
170 static int bfin_spi_flush(struct bfin_spi_master_data *drv_data)
171 {
172 unsigned long limit = loops_per_jiffy << 1;
173
174 /* wait for stop and clear stat */
175 while (!(read_STAT(drv_data) & BIT_STAT_SPIF) && --limit)
176 cpu_relax();
177
178 write_STAT(drv_data, BIT_STAT_CLR);
179
180 return limit;
181 }
182
183 /* Chip select operation functions for cs_change flag */
184 static void bfin_spi_cs_active(struct bfin_spi_master_data *drv_data, struct bfin_spi_slave_data *chip)
185 {
186 if (likely(chip->chip_select_num < MAX_CTRL_CS)) {
187 u16 flag = read_FLAG(drv_data);
188
189 flag &= ~chip->flag;
190
191 write_FLAG(drv_data, flag);
192 } else {
193 gpio_set_value(chip->cs_gpio, 0);
194 }
195 }
196
197 static void bfin_spi_cs_deactive(struct bfin_spi_master_data *drv_data,
198 struct bfin_spi_slave_data *chip)
199 {
200 if (likely(chip->chip_select_num < MAX_CTRL_CS)) {
201 u16 flag = read_FLAG(drv_data);
202
203 flag |= chip->flag;
204
205 write_FLAG(drv_data, flag);
206 } else {
207 gpio_set_value(chip->cs_gpio, 1);
208 }
209
210 /* Move delay here for consistency */
211 if (chip->cs_chg_udelay)
212 udelay(chip->cs_chg_udelay);
213 }
214
215 /* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
216 static inline void bfin_spi_cs_enable(struct bfin_spi_master_data *drv_data,
217 struct bfin_spi_slave_data *chip)
218 {
219 if (chip->chip_select_num < MAX_CTRL_CS) {
220 u16 flag = read_FLAG(drv_data);
221
222 flag |= (chip->flag >> 8);
223
224 write_FLAG(drv_data, flag);
225 }
226 }
227
228 static inline void bfin_spi_cs_disable(struct bfin_spi_master_data *drv_data,
229 struct bfin_spi_slave_data *chip)
230 {
231 if (chip->chip_select_num < MAX_CTRL_CS) {
232 u16 flag = read_FLAG(drv_data);
233
234 flag &= ~(chip->flag >> 8);
235
236 write_FLAG(drv_data, flag);
237 }
238 }
239
240 /* stop controller and re-config current chip*/
241 static void bfin_spi_restore_state(struct bfin_spi_master_data *drv_data)
242 {
243 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
244
245 /* Clear status and disable clock */
246 write_STAT(drv_data, BIT_STAT_CLR);
247 bfin_spi_disable(drv_data);
248 dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n");
249
250 SSYNC();
251
252 /* Load the registers */
253 write_CTRL(drv_data, chip->ctl_reg);
254 write_BAUD(drv_data, chip->baud);
255
256 bfin_spi_enable(drv_data);
257 bfin_spi_cs_active(drv_data, chip);
258 }
259
260 /* used to kick off transfer in rx mode and read unwanted RX data */
261 static inline void bfin_spi_dummy_read(struct bfin_spi_master_data *drv_data)
262 {
263 (void) read_RDBR(drv_data);
264 }
265
266 static void bfin_spi_u8_writer(struct bfin_spi_master_data *drv_data)
267 {
268 /* clear RXS (we check for RXS inside the loop) */
269 bfin_spi_dummy_read(drv_data);
270
271 while (drv_data->tx < drv_data->tx_end) {
272 write_TDBR(drv_data, (*(u8 *) (drv_data->tx++)));
273 /* wait until transfer finished.
274 checking SPIF or TXS may not guarantee transfer completion */
275 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
276 cpu_relax();
277 /* discard RX data and clear RXS */
278 bfin_spi_dummy_read(drv_data);
279 }
280 }
281
282 static void bfin_spi_u8_reader(struct bfin_spi_master_data *drv_data)
283 {
284 u16 tx_val = drv_data->cur_chip->idle_tx_val;
285
286 /* discard old RX data and clear RXS */
287 bfin_spi_dummy_read(drv_data);
288
289 while (drv_data->rx < drv_data->rx_end) {
290 write_TDBR(drv_data, tx_val);
291 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
292 cpu_relax();
293 *(u8 *) (drv_data->rx++) = read_RDBR(drv_data);
294 }
295 }
296
297 static void bfin_spi_u8_duplex(struct bfin_spi_master_data *drv_data)
298 {
299 /* discard old RX data and clear RXS */
300 bfin_spi_dummy_read(drv_data);
301
302 while (drv_data->rx < drv_data->rx_end) {
303 write_TDBR(drv_data, (*(u8 *) (drv_data->tx++)));
304 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
305 cpu_relax();
306 *(u8 *) (drv_data->rx++) = read_RDBR(drv_data);
307 }
308 }
309
310 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = {
311 .write = bfin_spi_u8_writer,
312 .read = bfin_spi_u8_reader,
313 .duplex = bfin_spi_u8_duplex,
314 };
315
316 static void bfin_spi_u16_writer(struct bfin_spi_master_data *drv_data)
317 {
318 /* clear RXS (we check for RXS inside the loop) */
319 bfin_spi_dummy_read(drv_data);
320
321 while (drv_data->tx < drv_data->tx_end) {
322 write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
323 drv_data->tx += 2;
324 /* wait until transfer finished.
325 checking SPIF or TXS may not guarantee transfer completion */
326 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
327 cpu_relax();
328 /* discard RX data and clear RXS */
329 bfin_spi_dummy_read(drv_data);
330 }
331 }
332
333 static void bfin_spi_u16_reader(struct bfin_spi_master_data *drv_data)
334 {
335 u16 tx_val = drv_data->cur_chip->idle_tx_val;
336
337 /* discard old RX data and clear RXS */
338 bfin_spi_dummy_read(drv_data);
339
340 while (drv_data->rx < drv_data->rx_end) {
341 write_TDBR(drv_data, tx_val);
342 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
343 cpu_relax();
344 *(u16 *) (drv_data->rx) = read_RDBR(drv_data);
345 drv_data->rx += 2;
346 }
347 }
348
349 static void bfin_spi_u16_duplex(struct bfin_spi_master_data *drv_data)
350 {
351 /* discard old RX data and clear RXS */
352 bfin_spi_dummy_read(drv_data);
353
354 while (drv_data->rx < drv_data->rx_end) {
355 write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
356 drv_data->tx += 2;
357 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
358 cpu_relax();
359 *(u16 *) (drv_data->rx) = read_RDBR(drv_data);
360 drv_data->rx += 2;
361 }
362 }
363
364 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = {
365 .write = bfin_spi_u16_writer,
366 .read = bfin_spi_u16_reader,
367 .duplex = bfin_spi_u16_duplex,
368 };
369
370 /* test if there is more transfer to be done */
371 static void *bfin_spi_next_transfer(struct bfin_spi_master_data *drv_data)
372 {
373 struct spi_message *msg = drv_data->cur_msg;
374 struct spi_transfer *trans = drv_data->cur_transfer;
375
376 /* Move to next transfer */
377 if (trans->transfer_list.next != &msg->transfers) {
378 drv_data->cur_transfer =
379 list_entry(trans->transfer_list.next,
380 struct spi_transfer, transfer_list);
381 return RUNNING_STATE;
382 } else
383 return DONE_STATE;
384 }
385
386 /*
387 * caller already set message->status;
388 * dma and pio irqs are blocked give finished message back
389 */
390 static void bfin_spi_giveback(struct bfin_spi_master_data *drv_data)
391 {
392 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
393 struct spi_transfer *last_transfer;
394 unsigned long flags;
395 struct spi_message *msg;
396
397 spin_lock_irqsave(&drv_data->lock, flags);
398 msg = drv_data->cur_msg;
399 drv_data->cur_msg = NULL;
400 drv_data->cur_transfer = NULL;
401 drv_data->cur_chip = NULL;
402 queue_work(drv_data->workqueue, &drv_data->pump_messages);
403 spin_unlock_irqrestore(&drv_data->lock, flags);
404
405 last_transfer = list_entry(msg->transfers.prev,
406 struct spi_transfer, transfer_list);
407
408 msg->state = NULL;
409
410 if (!drv_data->cs_change)
411 bfin_spi_cs_deactive(drv_data, chip);
412
413 /* Not stop spi in autobuffer mode */
414 if (drv_data->tx_dma != 0xFFFF)
415 bfin_spi_disable(drv_data);
416
417 if (msg->complete)
418 msg->complete(msg->context);
419 }
420
421 /* spi data irq handler */
422 static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id)
423 {
424 struct bfin_spi_master_data *drv_data = dev_id;
425 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
426 struct spi_message *msg = drv_data->cur_msg;
427 int n_bytes = drv_data->n_bytes;
428
429 /* wait until transfer finished. */
430 while (!(read_STAT(drv_data) & BIT_STAT_RXS))
431 cpu_relax();
432
433 if ((drv_data->tx && drv_data->tx >= drv_data->tx_end) ||
434 (drv_data->rx && drv_data->rx >= (drv_data->rx_end - n_bytes))) {
435 /* last read */
436 if (drv_data->rx) {
437 dev_dbg(&drv_data->pdev->dev, "last read\n");
438 if (n_bytes == 2)
439 *(u16 *) (drv_data->rx) = read_RDBR(drv_data);
440 else if (n_bytes == 1)
441 *(u8 *) (drv_data->rx) = read_RDBR(drv_data);
442 drv_data->rx += n_bytes;
443 }
444
445 msg->actual_length += drv_data->len_in_bytes;
446 if (drv_data->cs_change)
447 bfin_spi_cs_deactive(drv_data, chip);
448 /* Move to next transfer */
449 msg->state = bfin_spi_next_transfer(drv_data);
450
451 disable_irq_nosync(drv_data->spi_irq);
452
453 /* Schedule transfer tasklet */
454 tasklet_schedule(&drv_data->pump_transfers);
455 return IRQ_HANDLED;
456 }
457
458 if (drv_data->rx && drv_data->tx) {
459 /* duplex */
460 dev_dbg(&drv_data->pdev->dev, "duplex: write_TDBR\n");
461 if (drv_data->n_bytes == 2) {
462 *(u16 *) (drv_data->rx) = read_RDBR(drv_data);
463 write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
464 } else if (drv_data->n_bytes == 1) {
465 *(u8 *) (drv_data->rx) = read_RDBR(drv_data);
466 write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));
467 }
468 } else if (drv_data->rx) {
469 /* read */
470 dev_dbg(&drv_data->pdev->dev, "read: write_TDBR\n");
471 if (drv_data->n_bytes == 2)
472 *(u16 *) (drv_data->rx) = read_RDBR(drv_data);
473 else if (drv_data->n_bytes == 1)
474 *(u8 *) (drv_data->rx) = read_RDBR(drv_data);
475 write_TDBR(drv_data, chip->idle_tx_val);
476 } else if (drv_data->tx) {
477 /* write */
478 dev_dbg(&drv_data->pdev->dev, "write: write_TDBR\n");
479 bfin_spi_dummy_read(drv_data);
480 if (drv_data->n_bytes == 2)
481 write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
482 else if (drv_data->n_bytes == 1)
483 write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));
484 }
485
486 if (drv_data->tx)
487 drv_data->tx += n_bytes;
488 if (drv_data->rx)
489 drv_data->rx += n_bytes;
490
491 return IRQ_HANDLED;
492 }
493
494 static irqreturn_t bfin_spi_dma_irq_handler(int irq, void *dev_id)
495 {
496 struct bfin_spi_master_data *drv_data = dev_id;
497 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
498 struct spi_message *msg = drv_data->cur_msg;
499 unsigned long timeout;
500 unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel);
501 u16 spistat = read_STAT(drv_data);
502
503 dev_dbg(&drv_data->pdev->dev,
504 "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
505 dmastat, spistat);
506
507 if (drv_data->rx != NULL) {
508 u16 cr = read_CTRL(drv_data);
509 /* discard old RX data and clear RXS */
510 bfin_spi_dummy_read(drv_data);
511 write_CTRL(drv_data, cr & ~BIT_CTL_ENABLE); /* Disable SPI */
512 write_CTRL(drv_data, cr & ~BIT_CTL_TIMOD); /* Restore State */
513 write_STAT(drv_data, BIT_STAT_CLR); /* Clear Status */
514 }
515
516 clear_dma_irqstat(drv_data->dma_channel);
517
518 /*
519 * wait for the last transaction shifted out. HRM states:
520 * at this point there may still be data in the SPI DMA FIFO waiting
521 * to be transmitted ... software needs to poll TXS in the SPI_STAT
522 * register until it goes low for 2 successive reads
523 */
524 if (drv_data->tx != NULL) {
525 while ((read_STAT(drv_data) & BIT_STAT_TXS) ||
526 (read_STAT(drv_data) & BIT_STAT_TXS))
527 cpu_relax();
528 }
529
530 dev_dbg(&drv_data->pdev->dev,
531 "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
532 dmastat, read_STAT(drv_data));
533
534 timeout = jiffies + HZ;
535 while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
536 if (!time_before(jiffies, timeout)) {
537 dev_warn(&drv_data->pdev->dev, "timeout waiting for SPIF");
538 break;
539 } else
540 cpu_relax();
541
542 if ((dmastat & DMA_ERR) && (spistat & BIT_STAT_RBSY)) {
543 msg->state = ERROR_STATE;
544 dev_err(&drv_data->pdev->dev, "dma receive: fifo/buffer overflow\n");
545 } else {
546 msg->actual_length += drv_data->len_in_bytes;
547
548 if (drv_data->cs_change)
549 bfin_spi_cs_deactive(drv_data, chip);
550
551 /* Move to next transfer */
552 msg->state = bfin_spi_next_transfer(drv_data);
553 }
554
555 /* Schedule transfer tasklet */
556 tasklet_schedule(&drv_data->pump_transfers);
557
558 /* free the irq handler before next transfer */
559 dev_dbg(&drv_data->pdev->dev,
560 "disable dma channel irq%d\n",
561 drv_data->dma_channel);
562 dma_disable_irq_nosync(drv_data->dma_channel);
563
564 return IRQ_HANDLED;
565 }
566
567 static void bfin_spi_pump_transfers(unsigned long data)
568 {
569 struct bfin_spi_master_data *drv_data = (struct bfin_spi_master_data *)data;
570 struct spi_message *message = NULL;
571 struct spi_transfer *transfer = NULL;
572 struct spi_transfer *previous = NULL;
573 struct bfin_spi_slave_data *chip = NULL;
574 unsigned int bits_per_word;
575 u16 cr, cr_width, dma_width, dma_config;
576 u32 tranf_success = 1;
577 u8 full_duplex = 0;
578
579 /* Get current state information */
580 message = drv_data->cur_msg;
581 transfer = drv_data->cur_transfer;
582 chip = drv_data->cur_chip;
583
584 /*
585 * if msg is error or done, report it back using complete() callback
586 */
587
588 /* Handle for abort */
589 if (message->state == ERROR_STATE) {
590 dev_dbg(&drv_data->pdev->dev, "transfer: we've hit an error\n");
591 message->status = -EIO;
592 bfin_spi_giveback(drv_data);
593 return;
594 }
595
596 /* Handle end of message */
597 if (message->state == DONE_STATE) {
598 dev_dbg(&drv_data->pdev->dev, "transfer: all done!\n");
599 message->status = 0;
600 bfin_spi_giveback(drv_data);
601 return;
602 }
603
604 /* Delay if requested at end of transfer */
605 if (message->state == RUNNING_STATE) {
606 dev_dbg(&drv_data->pdev->dev, "transfer: still running ...\n");
607 previous = list_entry(transfer->transfer_list.prev,
608 struct spi_transfer, transfer_list);
609 if (previous->delay_usecs)
610 udelay(previous->delay_usecs);
611 }
612
613 /* Flush any existing transfers that may be sitting in the hardware */
614 if (bfin_spi_flush(drv_data) == 0) {
615 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
616 message->status = -EIO;
617 bfin_spi_giveback(drv_data);
618 return;
619 }
620
621 if (transfer->len == 0) {
622 /* Move to next transfer of this msg */
623 message->state = bfin_spi_next_transfer(drv_data);
624 /* Schedule next transfer tasklet */
625 tasklet_schedule(&drv_data->pump_transfers);
626 }
627
628 if (transfer->tx_buf != NULL) {
629 drv_data->tx = (void *)transfer->tx_buf;
630 drv_data->tx_end = drv_data->tx + transfer->len;
631 dev_dbg(&drv_data->pdev->dev, "tx_buf is %p, tx_end is %p\n",
632 transfer->tx_buf, drv_data->tx_end);
633 } else {
634 drv_data->tx = NULL;
635 }
636
637 if (transfer->rx_buf != NULL) {
638 full_duplex = transfer->tx_buf != NULL;
639 drv_data->rx = transfer->rx_buf;
640 drv_data->rx_end = drv_data->rx + transfer->len;
641 dev_dbg(&drv_data->pdev->dev, "rx_buf is %p, rx_end is %p\n",
642 transfer->rx_buf, drv_data->rx_end);
643 } else {
644 drv_data->rx = NULL;
645 }
646
647 drv_data->rx_dma = transfer->rx_dma;
648 drv_data->tx_dma = transfer->tx_dma;
649 drv_data->len_in_bytes = transfer->len;
650 drv_data->cs_change = transfer->cs_change;
651
652 /* Bits per word setup */
653 bits_per_word = transfer->bits_per_word ? : message->spi->bits_per_word;
654 if (bits_per_word == 8) {
655 drv_data->n_bytes = 1;
656 drv_data->len = transfer->len;
657 cr_width = 0;
658 drv_data->ops = &bfin_bfin_spi_transfer_ops_u8;
659 } else if (bits_per_word == 16) {
660 drv_data->n_bytes = 2;
661 drv_data->len = (transfer->len) >> 1;
662 cr_width = BIT_CTL_WORDSIZE;
663 drv_data->ops = &bfin_bfin_spi_transfer_ops_u16;
664 } else {
665 dev_err(&drv_data->pdev->dev, "transfer: unsupported bits_per_word\n");
666 message->status = -EINVAL;
667 bfin_spi_giveback(drv_data);
668 return;
669 }
670 cr = read_CTRL(drv_data) & ~(BIT_CTL_TIMOD | BIT_CTL_WORDSIZE);
671 cr |= cr_width;
672 write_CTRL(drv_data, cr);
673
674 dev_dbg(&drv_data->pdev->dev,
675 "transfer: drv_data->ops is %p, chip->ops is %p, u8_ops is %p\n",
676 drv_data->ops, chip->ops, &bfin_bfin_spi_transfer_ops_u8);
677
678 message->state = RUNNING_STATE;
679 dma_config = 0;
680
681 /* Speed setup (surely valid because already checked) */
682 if (transfer->speed_hz)
683 write_BAUD(drv_data, hz_to_spi_baud(transfer->speed_hz));
684 else
685 write_BAUD(drv_data, chip->baud);
686
687 write_STAT(drv_data, BIT_STAT_CLR);
688 bfin_spi_cs_active(drv_data, chip);
689
690 dev_dbg(&drv_data->pdev->dev,
691 "now pumping a transfer: width is %d, len is %d\n",
692 cr_width, transfer->len);
693
694 /*
695 * Try to map dma buffer and do a dma transfer. If successful use,
696 * different way to r/w according to the enable_dma settings and if
697 * we are not doing a full duplex transfer (since the hardware does
698 * not support full duplex DMA transfers).
699 */
700 if (!full_duplex && drv_data->cur_chip->enable_dma
701 && drv_data->len > 6) {
702
703 unsigned long dma_start_addr, flags;
704
705 disable_dma(drv_data->dma_channel);
706 clear_dma_irqstat(drv_data->dma_channel);
707
708 /* config dma channel */
709 dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n");
710 set_dma_x_count(drv_data->dma_channel, drv_data->len);
711 if (cr_width == BIT_CTL_WORDSIZE) {
712 set_dma_x_modify(drv_data->dma_channel, 2);
713 dma_width = WDSIZE_16;
714 } else {
715 set_dma_x_modify(drv_data->dma_channel, 1);
716 dma_width = WDSIZE_8;
717 }
718
719 /* poll for SPI completion before start */
720 while (!(read_STAT(drv_data) & BIT_STAT_SPIF))
721 cpu_relax();
722
723 /* dirty hack for autobuffer DMA mode */
724 if (drv_data->tx_dma == 0xFFFF) {
725 dev_dbg(&drv_data->pdev->dev,
726 "doing autobuffer DMA out.\n");
727
728 /* no irq in autobuffer mode */
729 dma_config =
730 (DMAFLOW_AUTO | RESTART | dma_width | DI_EN);
731 set_dma_config(drv_data->dma_channel, dma_config);
732 set_dma_start_addr(drv_data->dma_channel,
733 (unsigned long)drv_data->tx);
734 enable_dma(drv_data->dma_channel);
735
736 /* start SPI transfer */
737 write_CTRL(drv_data, cr | BIT_CTL_TIMOD_DMA_TX);
738
739 /* just return here, there can only be one transfer
740 * in this mode
741 */
742 message->status = 0;
743 bfin_spi_giveback(drv_data);
744 return;
745 }
746
747 /* In dma mode, rx or tx must be NULL in one transfer */
748 dma_config = (RESTART | dma_width | DI_EN);
749 if (drv_data->rx != NULL) {
750 /* set transfer mode, and enable SPI */
751 dev_dbg(&drv_data->pdev->dev, "doing DMA in to %p (size %zx)\n",
752 drv_data->rx, drv_data->len_in_bytes);
753
754 /* invalidate caches, if needed */
755 if (bfin_addr_dcacheable((unsigned long) drv_data->rx))
756 invalidate_dcache_range((unsigned long) drv_data->rx,
757 (unsigned long) (drv_data->rx +
758 drv_data->len_in_bytes));
759
760 dma_config |= WNR;
761 dma_start_addr = (unsigned long)drv_data->rx;
762 cr |= BIT_CTL_TIMOD_DMA_RX | BIT_CTL_SENDOPT;
763
764 } else if (drv_data->tx != NULL) {
765 dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n");
766
767 /* flush caches, if needed */
768 if (bfin_addr_dcacheable((unsigned long) drv_data->tx))
769 flush_dcache_range((unsigned long) drv_data->tx,
770 (unsigned long) (drv_data->tx +
771 drv_data->len_in_bytes));
772
773 dma_start_addr = (unsigned long)drv_data->tx;
774 cr |= BIT_CTL_TIMOD_DMA_TX;
775
776 } else
777 BUG();
778
779 /* oh man, here there be monsters ... and i dont mean the
780 * fluffy cute ones from pixar, i mean the kind that'll eat
781 * your data, kick your dog, and love it all. do *not* try
782 * and change these lines unless you (1) heavily test DMA
783 * with SPI flashes on a loaded system (e.g. ping floods),
784 * (2) know just how broken the DMA engine interaction with
785 * the SPI peripheral is, and (3) have someone else to blame
786 * when you screw it all up anyways.
787 */
788 set_dma_start_addr(drv_data->dma_channel, dma_start_addr);
789 set_dma_config(drv_data->dma_channel, dma_config);
790 local_irq_save(flags);
791 SSYNC();
792 write_CTRL(drv_data, cr);
793 enable_dma(drv_data->dma_channel);
794 dma_enable_irq(drv_data->dma_channel);
795 local_irq_restore(flags);
796
797 return;
798 }
799
800 /*
801 * We always use SPI_WRITE mode (transfer starts with TDBR write).
802 * SPI_READ mode (transfer starts with RDBR read) seems to have
803 * problems with setting up the output value in TDBR prior to the
804 * start of the transfer.
805 */
806 write_CTRL(drv_data, cr | BIT_CTL_TXMOD);
807
808 if (chip->pio_interrupt) {
809 /* SPI irq should have been disabled by now */
810
811 /* discard old RX data and clear RXS */
812 bfin_spi_dummy_read(drv_data);
813
814 /* start transfer */
815 if (drv_data->tx == NULL)
816 write_TDBR(drv_data, chip->idle_tx_val);
817 else {
818 if (bits_per_word == 8)
819 write_TDBR(drv_data, (*(u8 *) (drv_data->tx)));
820 else
821 write_TDBR(drv_data, (*(u16 *) (drv_data->tx)));
822 drv_data->tx += drv_data->n_bytes;
823 }
824
825 /* once TDBR is empty, interrupt is triggered */
826 enable_irq(drv_data->spi_irq);
827 return;
828 }
829
830 /* IO mode */
831 dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n");
832
833 if (full_duplex) {
834 /* full duplex mode */
835 BUG_ON((drv_data->tx_end - drv_data->tx) !=
836 (drv_data->rx_end - drv_data->rx));
837 dev_dbg(&drv_data->pdev->dev,
838 "IO duplex: cr is 0x%x\n", cr);
839
840 drv_data->ops->duplex(drv_data);
841
842 if (drv_data->tx != drv_data->tx_end)
843 tranf_success = 0;
844 } else if (drv_data->tx != NULL) {
845 /* write only half duplex */
846 dev_dbg(&drv_data->pdev->dev,
847 "IO write: cr is 0x%x\n", cr);
848
849 drv_data->ops->write(drv_data);
850
851 if (drv_data->tx != drv_data->tx_end)
852 tranf_success = 0;
853 } else if (drv_data->rx != NULL) {
854 /* read only half duplex */
855 dev_dbg(&drv_data->pdev->dev,
856 "IO read: cr is 0x%x\n", cr);
857
858 drv_data->ops->read(drv_data);
859 if (drv_data->rx != drv_data->rx_end)
860 tranf_success = 0;
861 }
862
863 if (!tranf_success) {
864 dev_dbg(&drv_data->pdev->dev,
865 "IO write error!\n");
866 message->state = ERROR_STATE;
867 } else {
868 /* Update total byte transfered */
869 message->actual_length += drv_data->len_in_bytes;
870 /* Move to next transfer of this msg */
871 message->state = bfin_spi_next_transfer(drv_data);
872 if (drv_data->cs_change)
873 bfin_spi_cs_deactive(drv_data, chip);
874 }
875
876 /* Schedule next transfer tasklet */
877 tasklet_schedule(&drv_data->pump_transfers);
878 }
879
880 /* pop a msg from queue and kick off real transfer */
881 static void bfin_spi_pump_messages(struct work_struct *work)
882 {
883 struct bfin_spi_master_data *drv_data;
884 unsigned long flags;
885
886 drv_data = container_of(work, struct bfin_spi_master_data, pump_messages);
887
888 /* Lock queue and check for queue work */
889 spin_lock_irqsave(&drv_data->lock, flags);
890 if (list_empty(&drv_data->queue) || !drv_data->running) {
891 /* pumper kicked off but no work to do */
892 drv_data->busy = 0;
893 spin_unlock_irqrestore(&drv_data->lock, flags);
894 return;
895 }
896
897 /* Make sure we are not already running a message */
898 if (drv_data->cur_msg) {
899 spin_unlock_irqrestore(&drv_data->lock, flags);
900 return;
901 }
902
903 /* Extract head of queue */
904 drv_data->cur_msg = list_entry(drv_data->queue.next,
905 struct spi_message, queue);
906
907 /* Setup the SSP using the per chip configuration */
908 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
909 bfin_spi_restore_state(drv_data);
910
911 list_del_init(&drv_data->cur_msg->queue);
912
913 /* Initial message state */
914 drv_data->cur_msg->state = START_STATE;
915 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
916 struct spi_transfer, transfer_list);
917
918 dev_dbg(&drv_data->pdev->dev, "got a message to pump, "
919 "state is set to: baud %d, flag 0x%x, ctl 0x%x\n",
920 drv_data->cur_chip->baud, drv_data->cur_chip->flag,
921 drv_data->cur_chip->ctl_reg);
922
923 dev_dbg(&drv_data->pdev->dev,
924 "the first transfer len is %d\n",
925 drv_data->cur_transfer->len);
926
927 /* Mark as busy and launch transfers */
928 tasklet_schedule(&drv_data->pump_transfers);
929
930 drv_data->busy = 1;
931 spin_unlock_irqrestore(&drv_data->lock, flags);
932 }
933
934 /*
935 * got a msg to transfer, queue it in drv_data->queue.
936 * And kick off message pumper
937 */
938 static int bfin_spi_transfer(struct spi_device *spi, struct spi_message *msg)
939 {
940 struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
941 unsigned long flags;
942
943 spin_lock_irqsave(&drv_data->lock, flags);
944
945 if (!drv_data->running) {
946 spin_unlock_irqrestore(&drv_data->lock, flags);
947 return -ESHUTDOWN;
948 }
949
950 msg->actual_length = 0;
951 msg->status = -EINPROGRESS;
952 msg->state = START_STATE;
953
954 dev_dbg(&spi->dev, "adding an msg in transfer() \n");
955 list_add_tail(&msg->queue, &drv_data->queue);
956
957 if (drv_data->running && !drv_data->busy)
958 queue_work(drv_data->workqueue, &drv_data->pump_messages);
959
960 spin_unlock_irqrestore(&drv_data->lock, flags);
961
962 return 0;
963 }
964
965 #define MAX_SPI_SSEL 7
966
967 static u16 ssel[][MAX_SPI_SSEL] = {
968 {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
969 P_SPI0_SSEL4, P_SPI0_SSEL5,
970 P_SPI0_SSEL6, P_SPI0_SSEL7},
971
972 {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
973 P_SPI1_SSEL4, P_SPI1_SSEL5,
974 P_SPI1_SSEL6, P_SPI1_SSEL7},
975
976 {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
977 P_SPI2_SSEL4, P_SPI2_SSEL5,
978 P_SPI2_SSEL6, P_SPI2_SSEL7},
979 };
980
981 /* setup for devices (may be called multiple times -- not just first setup) */
982 static int bfin_spi_setup(struct spi_device *spi)
983 {
984 struct bfin5xx_spi_chip *chip_info;
985 struct bfin_spi_slave_data *chip = NULL;
986 struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
987 u16 bfin_ctl_reg;
988 int ret = -EINVAL;
989
990 /* Only alloc (or use chip_info) on first setup */
991 chip_info = NULL;
992 chip = spi_get_ctldata(spi);
993 if (chip == NULL) {
994 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
995 if (!chip) {
996 dev_err(&spi->dev, "cannot allocate chip data\n");
997 ret = -ENOMEM;
998 goto error;
999 }
1000
1001 chip->enable_dma = 0;
1002 chip_info = spi->controller_data;
1003 }
1004
1005 /* Let people set non-standard bits directly */
1006 bfin_ctl_reg = BIT_CTL_OPENDRAIN | BIT_CTL_EMISO |
1007 BIT_CTL_PSSE | BIT_CTL_GM | BIT_CTL_SZ;
1008
1009 /* chip_info isn't always needed */
1010 if (chip_info) {
1011 /* Make sure people stop trying to set fields via ctl_reg
1012 * when they should actually be using common SPI framework.
1013 * Currently we let through: WOM EMISO PSSE GM SZ.
1014 * Not sure if a user actually needs/uses any of these,
1015 * but let's assume (for now) they do.
1016 */
1017 if (chip_info->ctl_reg & ~bfin_ctl_reg) {
1018 dev_err(&spi->dev, "do not set bits in ctl_reg "
1019 "that the SPI framework manages\n");
1020 goto error;
1021 }
1022 chip->enable_dma = chip_info->enable_dma != 0
1023 && drv_data->master_info->enable_dma;
1024 chip->ctl_reg = chip_info->ctl_reg;
1025 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
1026 chip->idle_tx_val = chip_info->idle_tx_val;
1027 chip->pio_interrupt = chip_info->pio_interrupt;
1028 spi->bits_per_word = chip_info->bits_per_word;
1029 } else {
1030 /* force a default base state */
1031 chip->ctl_reg &= bfin_ctl_reg;
1032 }
1033
1034 if (spi->bits_per_word != 8 && spi->bits_per_word != 16) {
1035 dev_err(&spi->dev, "%d bits_per_word is not supported\n",
1036 spi->bits_per_word);
1037 goto error;
1038 }
1039
1040 /* translate common spi framework into our register */
1041 if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) {
1042 dev_err(&spi->dev, "unsupported spi modes detected\n");
1043 goto error;
1044 }
1045 if (spi->mode & SPI_CPOL)
1046 chip->ctl_reg |= BIT_CTL_CPOL;
1047 if (spi->mode & SPI_CPHA)
1048 chip->ctl_reg |= BIT_CTL_CPHA;
1049 if (spi->mode & SPI_LSB_FIRST)
1050 chip->ctl_reg |= BIT_CTL_LSBF;
1051 /* we dont support running in slave mode (yet?) */
1052 chip->ctl_reg |= BIT_CTL_MASTER;
1053
1054 /*
1055 * Notice: for blackfin, the speed_hz is the value of register
1056 * SPI_BAUD, not the real baudrate
1057 */
1058 chip->baud = hz_to_spi_baud(spi->max_speed_hz);
1059 chip->chip_select_num = spi->chip_select;
1060 if (chip->chip_select_num < MAX_CTRL_CS) {
1061 if (!(spi->mode & SPI_CPHA))
1062 dev_warn(&spi->dev, "Warning: SPI CPHA not set:"
1063 " Slave Select not under software control!\n"
1064 " See Documentation/blackfin/bfin-spi-notes.txt");
1065
1066 chip->flag = (1 << spi->chip_select) << 8;
1067 } else
1068 chip->cs_gpio = chip->chip_select_num - MAX_CTRL_CS;
1069
1070 if (chip->enable_dma && chip->pio_interrupt) {
1071 dev_err(&spi->dev, "enable_dma is set, "
1072 "do not set pio_interrupt\n");
1073 goto error;
1074 }
1075 /*
1076 * if any one SPI chip is registered and wants DMA, request the
1077 * DMA channel for it
1078 */
1079 if (chip->enable_dma && !drv_data->dma_requested) {
1080 /* register dma irq handler */
1081 ret = request_dma(drv_data->dma_channel, "BFIN_SPI_DMA");
1082 if (ret) {
1083 dev_err(&spi->dev,
1084 "Unable to request BlackFin SPI DMA channel\n");
1085 goto error;
1086 }
1087 drv_data->dma_requested = 1;
1088
1089 ret = set_dma_callback(drv_data->dma_channel,
1090 bfin_spi_dma_irq_handler, drv_data);
1091 if (ret) {
1092 dev_err(&spi->dev, "Unable to set dma callback\n");
1093 goto error;
1094 }
1095 dma_disable_irq(drv_data->dma_channel);
1096 }
1097
1098 if (chip->pio_interrupt && !drv_data->irq_requested) {
1099 ret = request_irq(drv_data->spi_irq, bfin_spi_pio_irq_handler,
1100 IRQF_DISABLED, "BFIN_SPI", drv_data);
1101 if (ret) {
1102 dev_err(&spi->dev, "Unable to register spi IRQ\n");
1103 goto error;
1104 }
1105 drv_data->irq_requested = 1;
1106 /* we use write mode, spi irq has to be disabled here */
1107 disable_irq(drv_data->spi_irq);
1108 }
1109
1110 if (chip->chip_select_num >= MAX_CTRL_CS) {
1111 /* Only request on first setup */
1112 if (spi_get_ctldata(spi) == NULL) {
1113 ret = gpio_request(chip->cs_gpio, spi->modalias);
1114 if (ret) {
1115 dev_err(&spi->dev, "gpio_request() error\n");
1116 goto pin_error;
1117 }
1118 gpio_direction_output(chip->cs_gpio, 1);
1119 }
1120 }
1121
1122 dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d\n",
1123 spi->modalias, spi->bits_per_word, chip->enable_dma);
1124 dev_dbg(&spi->dev, "ctl_reg is 0x%x, flag_reg is 0x%x\n",
1125 chip->ctl_reg, chip->flag);
1126
1127 spi_set_ctldata(spi, chip);
1128
1129 dev_dbg(&spi->dev, "chip select number is %d\n", chip->chip_select_num);
1130 if (chip->chip_select_num < MAX_CTRL_CS) {
1131 ret = peripheral_request(ssel[spi->master->bus_num]
1132 [chip->chip_select_num-1], spi->modalias);
1133 if (ret) {
1134 dev_err(&spi->dev, "peripheral_request() error\n");
1135 goto pin_error;
1136 }
1137 }
1138
1139 bfin_spi_cs_enable(drv_data, chip);
1140 bfin_spi_cs_deactive(drv_data, chip);
1141
1142 return 0;
1143
1144 pin_error:
1145 if (chip->chip_select_num >= MAX_CTRL_CS)
1146 gpio_free(chip->cs_gpio);
1147 else
1148 peripheral_free(ssel[spi->master->bus_num]
1149 [chip->chip_select_num - 1]);
1150 error:
1151 if (chip) {
1152 if (drv_data->dma_requested)
1153 free_dma(drv_data->dma_channel);
1154 drv_data->dma_requested = 0;
1155
1156 kfree(chip);
1157 /* prevent free 'chip' twice */
1158 spi_set_ctldata(spi, NULL);
1159 }
1160
1161 return ret;
1162 }
1163
1164 /*
1165 * callback for spi framework.
1166 * clean driver specific data
1167 */
1168 static void bfin_spi_cleanup(struct spi_device *spi)
1169 {
1170 struct bfin_spi_slave_data *chip = spi_get_ctldata(spi);
1171 struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
1172
1173 if (!chip)
1174 return;
1175
1176 if (chip->chip_select_num < MAX_CTRL_CS) {
1177 peripheral_free(ssel[spi->master->bus_num]
1178 [chip->chip_select_num-1]);
1179 bfin_spi_cs_disable(drv_data, chip);
1180 } else
1181 gpio_free(chip->cs_gpio);
1182
1183 kfree(chip);
1184 /* prevent free 'chip' twice */
1185 spi_set_ctldata(spi, NULL);
1186 }
1187
1188 static inline int bfin_spi_init_queue(struct bfin_spi_master_data *drv_data)
1189 {
1190 INIT_LIST_HEAD(&drv_data->queue);
1191 spin_lock_init(&drv_data->lock);
1192
1193 drv_data->running = false;
1194 drv_data->busy = 0;
1195
1196 /* init transfer tasklet */
1197 tasklet_init(&drv_data->pump_transfers,
1198 bfin_spi_pump_transfers, (unsigned long)drv_data);
1199
1200 /* init messages workqueue */
1201 INIT_WORK(&drv_data->pump_messages, bfin_spi_pump_messages);
1202 drv_data->workqueue = create_singlethread_workqueue(
1203 dev_name(drv_data->master->dev.parent));
1204 if (drv_data->workqueue == NULL)
1205 return -EBUSY;
1206
1207 return 0;
1208 }
1209
1210 static inline int bfin_spi_start_queue(struct bfin_spi_master_data *drv_data)
1211 {
1212 unsigned long flags;
1213
1214 spin_lock_irqsave(&drv_data->lock, flags);
1215
1216 if (drv_data->running || drv_data->busy) {
1217 spin_unlock_irqrestore(&drv_data->lock, flags);
1218 return -EBUSY;
1219 }
1220
1221 drv_data->running = true;
1222 drv_data->cur_msg = NULL;
1223 drv_data->cur_transfer = NULL;
1224 drv_data->cur_chip = NULL;
1225 spin_unlock_irqrestore(&drv_data->lock, flags);
1226
1227 queue_work(drv_data->workqueue, &drv_data->pump_messages);
1228
1229 return 0;
1230 }
1231
1232 static inline int bfin_spi_stop_queue(struct bfin_spi_master_data *drv_data)
1233 {
1234 unsigned long flags;
1235 unsigned limit = 500;
1236 int status = 0;
1237
1238 spin_lock_irqsave(&drv_data->lock, flags);
1239
1240 /*
1241 * This is a bit lame, but is optimized for the common execution path.
1242 * A wait_queue on the drv_data->busy could be used, but then the common
1243 * execution path (pump_messages) would be required to call wake_up or
1244 * friends on every SPI message. Do this instead
1245 */
1246 drv_data->running = false;
1247 while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {
1248 spin_unlock_irqrestore(&drv_data->lock, flags);
1249 msleep(10);
1250 spin_lock_irqsave(&drv_data->lock, flags);
1251 }
1252
1253 if (!list_empty(&drv_data->queue) || drv_data->busy)
1254 status = -EBUSY;
1255
1256 spin_unlock_irqrestore(&drv_data->lock, flags);
1257
1258 return status;
1259 }
1260
1261 static inline int bfin_spi_destroy_queue(struct bfin_spi_master_data *drv_data)
1262 {
1263 int status;
1264
1265 status = bfin_spi_stop_queue(drv_data);
1266 if (status != 0)
1267 return status;
1268
1269 destroy_workqueue(drv_data->workqueue);
1270
1271 return 0;
1272 }
1273
1274 static int __init bfin_spi_probe(struct platform_device *pdev)
1275 {
1276 struct device *dev = &pdev->dev;
1277 struct bfin5xx_spi_master *platform_info;
1278 struct spi_master *master;
1279 struct bfin_spi_master_data *drv_data;
1280 struct resource *res;
1281 int status = 0;
1282
1283 platform_info = dev->platform_data;
1284
1285 /* Allocate master with space for drv_data */
1286 master = spi_alloc_master(dev, sizeof(*drv_data));
1287 if (!master) {
1288 dev_err(&pdev->dev, "can not alloc spi_master\n");
1289 return -ENOMEM;
1290 }
1291
1292 drv_data = spi_master_get_devdata(master);
1293 drv_data->master = master;
1294 drv_data->master_info = platform_info;
1295 drv_data->pdev = pdev;
1296 drv_data->pin_req = platform_info->pin_req;
1297
1298 /* the spi->mode bits supported by this driver: */
1299 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1300
1301 master->bus_num = pdev->id;
1302 master->num_chipselect = platform_info->num_chipselect;
1303 master->cleanup = bfin_spi_cleanup;
1304 master->setup = bfin_spi_setup;
1305 master->transfer = bfin_spi_transfer;
1306
1307 /* Find and map our resources */
1308 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1309 if (res == NULL) {
1310 dev_err(dev, "Cannot get IORESOURCE_MEM\n");
1311 status = -ENOENT;
1312 goto out_error_get_res;
1313 }
1314
1315 drv_data->regs_base = ioremap(res->start, resource_size(res));
1316 if (drv_data->regs_base == NULL) {
1317 dev_err(dev, "Cannot map IO\n");
1318 status = -ENXIO;
1319 goto out_error_ioremap;
1320 }
1321
1322 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1323 if (res == NULL) {
1324 dev_err(dev, "No DMA channel specified\n");
1325 status = -ENOENT;
1326 goto out_error_free_io;
1327 }
1328 drv_data->dma_channel = res->start;
1329
1330 drv_data->spi_irq = platform_get_irq(pdev, 0);
1331 if (drv_data->spi_irq < 0) {
1332 dev_err(dev, "No spi pio irq specified\n");
1333 status = -ENOENT;
1334 goto out_error_free_io;
1335 }
1336
1337 /* Initial and start queue */
1338 status = bfin_spi_init_queue(drv_data);
1339 if (status != 0) {
1340 dev_err(dev, "problem initializing queue\n");
1341 goto out_error_queue_alloc;
1342 }
1343
1344 status = bfin_spi_start_queue(drv_data);
1345 if (status != 0) {
1346 dev_err(dev, "problem starting queue\n");
1347 goto out_error_queue_alloc;
1348 }
1349
1350 status = peripheral_request_list(drv_data->pin_req, DRV_NAME);
1351 if (status != 0) {
1352 dev_err(&pdev->dev, ": Requesting Peripherals failed\n");
1353 goto out_error_queue_alloc;
1354 }
1355
1356 /* Reset SPI registers. If these registers were used by the boot loader,
1357 * the sky may fall on your head if you enable the dma controller.
1358 */
1359 write_CTRL(drv_data, BIT_CTL_CPHA | BIT_CTL_MASTER);
1360 write_FLAG(drv_data, 0xFF00);
1361
1362 /* Register with the SPI framework */
1363 platform_set_drvdata(pdev, drv_data);
1364 status = spi_register_master(master);
1365 if (status != 0) {
1366 dev_err(dev, "problem registering spi master\n");
1367 goto out_error_queue_alloc;
1368 }
1369
1370 dev_info(dev, "%s, Version %s, regs_base@%p, dma channel@%d\n",
1371 DRV_DESC, DRV_VERSION, drv_data->regs_base,
1372 drv_data->dma_channel);
1373 return status;
1374
1375 out_error_queue_alloc:
1376 bfin_spi_destroy_queue(drv_data);
1377 out_error_free_io:
1378 iounmap((void *) drv_data->regs_base);
1379 out_error_ioremap:
1380 out_error_get_res:
1381 spi_master_put(master);
1382
1383 return status;
1384 }
1385
1386 /* stop hardware and remove the driver */
1387 static int __devexit bfin_spi_remove(struct platform_device *pdev)
1388 {
1389 struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev);
1390 int status = 0;
1391
1392 if (!drv_data)
1393 return 0;
1394
1395 /* Remove the queue */
1396 status = bfin_spi_destroy_queue(drv_data);
1397 if (status != 0)
1398 return status;
1399
1400 /* Disable the SSP at the peripheral and SOC level */
1401 bfin_spi_disable(drv_data);
1402
1403 /* Release DMA */
1404 if (drv_data->master_info->enable_dma) {
1405 if (dma_channel_active(drv_data->dma_channel))
1406 free_dma(drv_data->dma_channel);
1407 }
1408
1409 if (drv_data->irq_requested) {
1410 free_irq(drv_data->spi_irq, drv_data);
1411 drv_data->irq_requested = 0;
1412 }
1413
1414 /* Disconnect from the SPI framework */
1415 spi_unregister_master(drv_data->master);
1416
1417 peripheral_free_list(drv_data->pin_req);
1418
1419 /* Prevent double remove */
1420 platform_set_drvdata(pdev, NULL);
1421
1422 return 0;
1423 }
1424
1425 #ifdef CONFIG_PM
1426 static int bfin_spi_suspend(struct platform_device *pdev, pm_message_t state)
1427 {
1428 struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev);
1429 int status = 0;
1430
1431 status = bfin_spi_stop_queue(drv_data);
1432 if (status != 0)
1433 return status;
1434
1435 drv_data->ctrl_reg = read_CTRL(drv_data);
1436 drv_data->flag_reg = read_FLAG(drv_data);
1437
1438 /*
1439 * reset SPI_CTL and SPI_FLG registers
1440 */
1441 write_CTRL(drv_data, BIT_CTL_CPHA | BIT_CTL_MASTER);
1442 write_FLAG(drv_data, 0xFF00);
1443
1444 return 0;
1445 }
1446
1447 static int bfin_spi_resume(struct platform_device *pdev)
1448 {
1449 struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev);
1450 int status = 0;
1451
1452 write_CTRL(drv_data, drv_data->ctrl_reg);
1453 write_FLAG(drv_data, drv_data->flag_reg);
1454
1455 /* Start the queue running */
1456 status = bfin_spi_start_queue(drv_data);
1457 if (status != 0) {
1458 dev_err(&pdev->dev, "problem starting queue (%d)\n", status);
1459 return status;
1460 }
1461
1462 return 0;
1463 }
1464 #else
1465 #define bfin_spi_suspend NULL
1466 #define bfin_spi_resume NULL
1467 #endif /* CONFIG_PM */
1468
1469 MODULE_ALIAS("platform:bfin-spi");
1470 static struct platform_driver bfin_spi_driver = {
1471 .driver = {
1472 .name = DRV_NAME,
1473 .owner = THIS_MODULE,
1474 },
1475 .suspend = bfin_spi_suspend,
1476 .resume = bfin_spi_resume,
1477 .remove = __devexit_p(bfin_spi_remove),
1478 };
1479
1480 static int __init bfin_spi_init(void)
1481 {
1482 return platform_driver_probe(&bfin_spi_driver, bfin_spi_probe);
1483 }
1484 subsys_initcall(bfin_spi_init);
1485
1486 static void __exit bfin_spi_exit(void)
1487 {
1488 platform_driver_unregister(&bfin_spi_driver);
1489 }
1490 module_exit(bfin_spi_exit);
Linux with added FPC-III support