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Linux 4.2.1
[linux/fpc-iii.git] / drivers / spi / spi-bfin5xx.c
bloba3d65b4f49445d144fcba077ce3413630300e8c8
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/gpio.h>
16 #include <linux/slab.h>
17 #include <linux/io.h>
18 #include <linux/ioport.h>
19 #include <linux/irq.h>
20 #include <linux/errno.h>
21 #include <linux/interrupt.h>
22 #include <linux/platform_device.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/spi/spi.h>
25 #include <linux/workqueue.h>
26
27 #include <asm/dma.h>
28 #include <asm/portmux.h>
29 #include <asm/bfin5xx_spi.h>
30 #include <asm/cacheflush.h>
31
32 #define DRV_NAME "bfin-spi"
33 #define DRV_AUTHOR "Bryan Wu, Luke Yang"
34 #define DRV_DESC "Blackfin on-chip SPI Controller Driver"
35 #define DRV_VERSION "1.0"
36
37 MODULE_AUTHOR(DRV_AUTHOR);
38 MODULE_DESCRIPTION(DRV_DESC);
39 MODULE_LICENSE("GPL");
40
41 #define START_STATE ((void *)0)
42 #define RUNNING_STATE ((void *)1)
43 #define DONE_STATE ((void *)2)
44 #define ERROR_STATE ((void *)-1)
45
46 struct bfin_spi_master_data;
47
48 struct bfin_spi_transfer_ops {
49 void (*write) (struct bfin_spi_master_data *);
50 void (*read) (struct bfin_spi_master_data *);
51 void (*duplex) (struct bfin_spi_master_data *);
52 };
53
54 struct bfin_spi_master_data {
55 /* Driver model hookup */
56 struct platform_device *pdev;
57
58 /* SPI framework hookup */
59 struct spi_master *master;
60
61 /* Regs base of SPI controller */
62 struct bfin_spi_regs __iomem *regs;
63
64 /* Pin request list */
65 u16 *pin_req;
66
67 /* BFIN hookup */
68 struct bfin5xx_spi_master *master_info;
69
70 /* Driver message queue */
71 struct workqueue_struct *workqueue;
72 struct work_struct pump_messages;
73 spinlock_t lock;
74 struct list_head queue;
75 int busy;
76 bool running;
77
78 /* Message Transfer pump */
79 struct tasklet_struct pump_transfers;
80
81 /* Current message transfer state info */
82 struct spi_message *cur_msg;
83 struct spi_transfer *cur_transfer;
84 struct bfin_spi_slave_data *cur_chip;
85 size_t len_in_bytes;
86 size_t len;
87 void *tx;
88 void *tx_end;
89 void *rx;
90 void *rx_end;
91
92 /* DMA stuffs */
93 int dma_channel;
94 int dma_mapped;
95 int dma_requested;
96 dma_addr_t rx_dma;
97 dma_addr_t tx_dma;
98
99 int irq_requested;
100 int spi_irq;
101
102 size_t rx_map_len;
103 size_t tx_map_len;
104 u8 n_bytes;
105 u16 ctrl_reg;
106 u16 flag_reg;
107
108 int cs_change;
109 const struct bfin_spi_transfer_ops *ops;
110 };
111
112 struct bfin_spi_slave_data {
113 u16 ctl_reg;
114 u16 baud;
115 u16 flag;
116
117 u8 chip_select_num;
118 u8 enable_dma;
119 u16 cs_chg_udelay; /* Some devices require > 255usec delay */
120 u32 cs_gpio;
121 u16 idle_tx_val;
122 u8 pio_interrupt; /* use spi data irq */
123 const struct bfin_spi_transfer_ops *ops;
124 };
125
126 static void bfin_spi_enable(struct bfin_spi_master_data *drv_data)
127 {
128 bfin_write_or(&drv_data->regs->ctl, BIT_CTL_ENABLE);
129 }
130
131 static void bfin_spi_disable(struct bfin_spi_master_data *drv_data)
132 {
133 bfin_write_and(&drv_data->regs->ctl, ~BIT_CTL_ENABLE);
134 }
135
136 /* Caculate the SPI_BAUD register value based on input HZ */
137 static u16 hz_to_spi_baud(u32 speed_hz)
138 {
139 u_long sclk = get_sclk();
140 u16 spi_baud = (sclk / (2 * speed_hz));
141
142 if ((sclk % (2 * speed_hz)) > 0)
143 spi_baud++;
144
145 if (spi_baud < MIN_SPI_BAUD_VAL)
146 spi_baud = MIN_SPI_BAUD_VAL;
147
148 return spi_baud;
149 }
150
151 static int bfin_spi_flush(struct bfin_spi_master_data *drv_data)
152 {
153 unsigned long limit = loops_per_jiffy << 1;
154
155 /* wait for stop and clear stat */
156 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_SPIF) && --limit)
157 cpu_relax();
158
159 bfin_write(&drv_data->regs->stat, BIT_STAT_CLR);
160
161 return limit;
162 }
163
164 /* Chip select operation functions for cs_change flag */
165 static void bfin_spi_cs_active(struct bfin_spi_master_data *drv_data, struct bfin_spi_slave_data *chip)
166 {
167 if (likely(chip->chip_select_num < MAX_CTRL_CS))
168 bfin_write_and(&drv_data->regs->flg, ~chip->flag);
169 else
170 gpio_set_value(chip->cs_gpio, 0);
171 }
172
173 static void bfin_spi_cs_deactive(struct bfin_spi_master_data *drv_data,
174 struct bfin_spi_slave_data *chip)
175 {
176 if (likely(chip->chip_select_num < MAX_CTRL_CS))
177 bfin_write_or(&drv_data->regs->flg, chip->flag);
178 else
179 gpio_set_value(chip->cs_gpio, 1);
180
181 /* Move delay here for consistency */
182 if (chip->cs_chg_udelay)
183 udelay(chip->cs_chg_udelay);
184 }
185
186 /* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
187 static inline void bfin_spi_cs_enable(struct bfin_spi_master_data *drv_data,
188 struct bfin_spi_slave_data *chip)
189 {
190 if (chip->chip_select_num < MAX_CTRL_CS)
191 bfin_write_or(&drv_data->regs->flg, chip->flag >> 8);
192 }
193
194 static inline void bfin_spi_cs_disable(struct bfin_spi_master_data *drv_data,
195 struct bfin_spi_slave_data *chip)
196 {
197 if (chip->chip_select_num < MAX_CTRL_CS)
198 bfin_write_and(&drv_data->regs->flg, ~(chip->flag >> 8));
199 }
200
201 /* stop controller and re-config current chip*/
202 static void bfin_spi_restore_state(struct bfin_spi_master_data *drv_data)
203 {
204 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
205
206 /* Clear status and disable clock */
207 bfin_write(&drv_data->regs->stat, BIT_STAT_CLR);
208 bfin_spi_disable(drv_data);
209 dev_dbg(&drv_data->pdev->dev, "restoring spi ctl state\n");
210
211 SSYNC();
212
213 /* Load the registers */
214 bfin_write(&drv_data->regs->ctl, chip->ctl_reg);
215 bfin_write(&drv_data->regs->baud, chip->baud);
216
217 bfin_spi_enable(drv_data);
218 bfin_spi_cs_active(drv_data, chip);
219 }
220
221 /* used to kick off transfer in rx mode and read unwanted RX data */
222 static inline void bfin_spi_dummy_read(struct bfin_spi_master_data *drv_data)
223 {
224 (void) bfin_read(&drv_data->regs->rdbr);
225 }
226
227 static void bfin_spi_u8_writer(struct bfin_spi_master_data *drv_data)
228 {
229 /* clear RXS (we check for RXS inside the loop) */
230 bfin_spi_dummy_read(drv_data);
231
232 while (drv_data->tx < drv_data->tx_end) {
233 bfin_write(&drv_data->regs->tdbr, (*(u8 *) (drv_data->tx++)));
234 /* wait until transfer finished.
235 checking SPIF or TXS may not guarantee transfer completion */
236 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
237 cpu_relax();
238 /* discard RX data and clear RXS */
239 bfin_spi_dummy_read(drv_data);
240 }
241 }
242
243 static void bfin_spi_u8_reader(struct bfin_spi_master_data *drv_data)
244 {
245 u16 tx_val = drv_data->cur_chip->idle_tx_val;
246
247 /* discard old RX data and clear RXS */
248 bfin_spi_dummy_read(drv_data);
249
250 while (drv_data->rx < drv_data->rx_end) {
251 bfin_write(&drv_data->regs->tdbr, tx_val);
252 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
253 cpu_relax();
254 *(u8 *) (drv_data->rx++) = bfin_read(&drv_data->regs->rdbr);
255 }
256 }
257
258 static void bfin_spi_u8_duplex(struct bfin_spi_master_data *drv_data)
259 {
260 /* discard old RX data and clear RXS */
261 bfin_spi_dummy_read(drv_data);
262
263 while (drv_data->rx < drv_data->rx_end) {
264 bfin_write(&drv_data->regs->tdbr, (*(u8 *) (drv_data->tx++)));
265 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
266 cpu_relax();
267 *(u8 *) (drv_data->rx++) = bfin_read(&drv_data->regs->rdbr);
268 }
269 }
270
271 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = {
272 .write = bfin_spi_u8_writer,
273 .read = bfin_spi_u8_reader,
274 .duplex = bfin_spi_u8_duplex,
275 };
276
277 static void bfin_spi_u16_writer(struct bfin_spi_master_data *drv_data)
278 {
279 /* clear RXS (we check for RXS inside the loop) */
280 bfin_spi_dummy_read(drv_data);
281
282 while (drv_data->tx < drv_data->tx_end) {
283 bfin_write(&drv_data->regs->tdbr, (*(u16 *) (drv_data->tx)));
284 drv_data->tx += 2;
285 /* wait until transfer finished.
286 checking SPIF or TXS may not guarantee transfer completion */
287 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
288 cpu_relax();
289 /* discard RX data and clear RXS */
290 bfin_spi_dummy_read(drv_data);
291 }
292 }
293
294 static void bfin_spi_u16_reader(struct bfin_spi_master_data *drv_data)
295 {
296 u16 tx_val = drv_data->cur_chip->idle_tx_val;
297
298 /* discard old RX data and clear RXS */
299 bfin_spi_dummy_read(drv_data);
300
301 while (drv_data->rx < drv_data->rx_end) {
302 bfin_write(&drv_data->regs->tdbr, tx_val);
303 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
304 cpu_relax();
305 *(u16 *) (drv_data->rx) = bfin_read(&drv_data->regs->rdbr);
306 drv_data->rx += 2;
307 }
308 }
309
310 static void bfin_spi_u16_duplex(struct bfin_spi_master_data *drv_data)
311 {
312 /* discard old RX data and clear RXS */
313 bfin_spi_dummy_read(drv_data);
314
315 while (drv_data->rx < drv_data->rx_end) {
316 bfin_write(&drv_data->regs->tdbr, (*(u16 *) (drv_data->tx)));
317 drv_data->tx += 2;
318 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
319 cpu_relax();
320 *(u16 *) (drv_data->rx) = bfin_read(&drv_data->regs->rdbr);
321 drv_data->rx += 2;
322 }
323 }
324
325 static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = {
326 .write = bfin_spi_u16_writer,
327 .read = bfin_spi_u16_reader,
328 .duplex = bfin_spi_u16_duplex,
329 };
330
331 /* test if there is more transfer to be done */
332 static void *bfin_spi_next_transfer(struct bfin_spi_master_data *drv_data)
333 {
334 struct spi_message *msg = drv_data->cur_msg;
335 struct spi_transfer *trans = drv_data->cur_transfer;
336
337 /* Move to next transfer */
338 if (trans->transfer_list.next != &msg->transfers) {
339 drv_data->cur_transfer =
340 list_entry(trans->transfer_list.next,
341 struct spi_transfer, transfer_list);
342 return RUNNING_STATE;
343 } else
344 return DONE_STATE;
345 }
346
347 /*
348 * caller already set message->status;
349 * dma and pio irqs are blocked give finished message back
350 */
351 static void bfin_spi_giveback(struct bfin_spi_master_data *drv_data)
352 {
353 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
354 unsigned long flags;
355 struct spi_message *msg;
356
357 spin_lock_irqsave(&drv_data->lock, flags);
358 msg = drv_data->cur_msg;
359 drv_data->cur_msg = NULL;
360 drv_data->cur_transfer = NULL;
361 drv_data->cur_chip = NULL;
362 queue_work(drv_data->workqueue, &drv_data->pump_messages);
363 spin_unlock_irqrestore(&drv_data->lock, flags);
364
365 msg->state = NULL;
366
367 if (!drv_data->cs_change)
368 bfin_spi_cs_deactive(drv_data, chip);
369
370 /* Not stop spi in autobuffer mode */
371 if (drv_data->tx_dma != 0xFFFF)
372 bfin_spi_disable(drv_data);
373
374 if (msg->complete)
375 msg->complete(msg->context);
376 }
377
378 /* spi data irq handler */
379 static irqreturn_t bfin_spi_pio_irq_handler(int irq, void *dev_id)
380 {
381 struct bfin_spi_master_data *drv_data = dev_id;
382 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
383 struct spi_message *msg = drv_data->cur_msg;
384 int n_bytes = drv_data->n_bytes;
385 int loop = 0;
386
387 /* wait until transfer finished. */
388 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_RXS))
389 cpu_relax();
390
391 if ((drv_data->tx && drv_data->tx >= drv_data->tx_end) ||
392 (drv_data->rx && drv_data->rx >= (drv_data->rx_end - n_bytes))) {
393 /* last read */
394 if (drv_data->rx) {
395 dev_dbg(&drv_data->pdev->dev, "last read\n");
396 if (!(n_bytes % 2)) {
397 u16 *buf = (u16 *)drv_data->rx;
398 for (loop = 0; loop < n_bytes / 2; loop++)
399 *buf++ = bfin_read(&drv_data->regs->rdbr);
400 } else {
401 u8 *buf = (u8 *)drv_data->rx;
402 for (loop = 0; loop < n_bytes; loop++)
403 *buf++ = bfin_read(&drv_data->regs->rdbr);
404 }
405 drv_data->rx += n_bytes;
406 }
407
408 msg->actual_length += drv_data->len_in_bytes;
409 if (drv_data->cs_change)
410 bfin_spi_cs_deactive(drv_data, chip);
411 /* Move to next transfer */
412 msg->state = bfin_spi_next_transfer(drv_data);
413
414 disable_irq_nosync(drv_data->spi_irq);
415
416 /* Schedule transfer tasklet */
417 tasklet_schedule(&drv_data->pump_transfers);
418 return IRQ_HANDLED;
419 }
420
421 if (drv_data->rx && drv_data->tx) {
422 /* duplex */
423 dev_dbg(&drv_data->pdev->dev, "duplex: write_TDBR\n");
424 if (!(n_bytes % 2)) {
425 u16 *buf = (u16 *)drv_data->rx;
426 u16 *buf2 = (u16 *)drv_data->tx;
427 for (loop = 0; loop < n_bytes / 2; loop++) {
428 *buf++ = bfin_read(&drv_data->regs->rdbr);
429 bfin_write(&drv_data->regs->tdbr, *buf2++);
430 }
431 } else {
432 u8 *buf = (u8 *)drv_data->rx;
433 u8 *buf2 = (u8 *)drv_data->tx;
434 for (loop = 0; loop < n_bytes; loop++) {
435 *buf++ = bfin_read(&drv_data->regs->rdbr);
436 bfin_write(&drv_data->regs->tdbr, *buf2++);
437 }
438 }
439 } else if (drv_data->rx) {
440 /* read */
441 dev_dbg(&drv_data->pdev->dev, "read: write_TDBR\n");
442 if (!(n_bytes % 2)) {
443 u16 *buf = (u16 *)drv_data->rx;
444 for (loop = 0; loop < n_bytes / 2; loop++) {
445 *buf++ = bfin_read(&drv_data->regs->rdbr);
446 bfin_write(&drv_data->regs->tdbr, chip->idle_tx_val);
447 }
448 } else {
449 u8 *buf = (u8 *)drv_data->rx;
450 for (loop = 0; loop < n_bytes; loop++) {
451 *buf++ = bfin_read(&drv_data->regs->rdbr);
452 bfin_write(&drv_data->regs->tdbr, chip->idle_tx_val);
453 }
454 }
455 } else if (drv_data->tx) {
456 /* write */
457 dev_dbg(&drv_data->pdev->dev, "write: write_TDBR\n");
458 if (!(n_bytes % 2)) {
459 u16 *buf = (u16 *)drv_data->tx;
460 for (loop = 0; loop < n_bytes / 2; loop++) {
461 bfin_read(&drv_data->regs->rdbr);
462 bfin_write(&drv_data->regs->tdbr, *buf++);
463 }
464 } else {
465 u8 *buf = (u8 *)drv_data->tx;
466 for (loop = 0; loop < n_bytes; loop++) {
467 bfin_read(&drv_data->regs->rdbr);
468 bfin_write(&drv_data->regs->tdbr, *buf++);
469 }
470 }
471 }
472
473 if (drv_data->tx)
474 drv_data->tx += n_bytes;
475 if (drv_data->rx)
476 drv_data->rx += n_bytes;
477
478 return IRQ_HANDLED;
479 }
480
481 static irqreturn_t bfin_spi_dma_irq_handler(int irq, void *dev_id)
482 {
483 struct bfin_spi_master_data *drv_data = dev_id;
484 struct bfin_spi_slave_data *chip = drv_data->cur_chip;
485 struct spi_message *msg = drv_data->cur_msg;
486 unsigned long timeout;
487 unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel);
488 u16 spistat = bfin_read(&drv_data->regs->stat);
489
490 dev_dbg(&drv_data->pdev->dev,
491 "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
492 dmastat, spistat);
493
494 if (drv_data->rx != NULL) {
495 u16 cr = bfin_read(&drv_data->regs->ctl);
496 /* discard old RX data and clear RXS */
497 bfin_spi_dummy_read(drv_data);
498 bfin_write(&drv_data->regs->ctl, cr & ~BIT_CTL_ENABLE); /* Disable SPI */
499 bfin_write(&drv_data->regs->ctl, cr & ~BIT_CTL_TIMOD); /* Restore State */
500 bfin_write(&drv_data->regs->stat, BIT_STAT_CLR); /* Clear Status */
501 }
502
503 clear_dma_irqstat(drv_data->dma_channel);
504
505 /*
506 * wait for the last transaction shifted out. HRM states:
507 * at this point there may still be data in the SPI DMA FIFO waiting
508 * to be transmitted ... software needs to poll TXS in the SPI_STAT
509 * register until it goes low for 2 successive reads
510 */
511 if (drv_data->tx != NULL) {
512 while ((bfin_read(&drv_data->regs->stat) & BIT_STAT_TXS) ||
513 (bfin_read(&drv_data->regs->stat) & BIT_STAT_TXS))
514 cpu_relax();
515 }
516
517 dev_dbg(&drv_data->pdev->dev,
518 "in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
519 dmastat, bfin_read(&drv_data->regs->stat));
520
521 timeout = jiffies + HZ;
522 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_SPIF))
523 if (!time_before(jiffies, timeout)) {
524 dev_warn(&drv_data->pdev->dev, "timeout waiting for SPIF\n");
525 break;
526 } else
527 cpu_relax();
528
529 if ((dmastat & DMA_ERR) && (spistat & BIT_STAT_RBSY)) {
530 msg->state = ERROR_STATE;
531 dev_err(&drv_data->pdev->dev, "dma receive: fifo/buffer overflow\n");
532 } else {
533 msg->actual_length += drv_data->len_in_bytes;
534
535 if (drv_data->cs_change)
536 bfin_spi_cs_deactive(drv_data, chip);
537
538 /* Move to next transfer */
539 msg->state = bfin_spi_next_transfer(drv_data);
540 }
541
542 /* Schedule transfer tasklet */
543 tasklet_schedule(&drv_data->pump_transfers);
544
545 /* free the irq handler before next transfer */
546 dev_dbg(&drv_data->pdev->dev,
547 "disable dma channel irq%d\n",
548 drv_data->dma_channel);
549 dma_disable_irq_nosync(drv_data->dma_channel);
550
551 return IRQ_HANDLED;
552 }
553
554 static void bfin_spi_pump_transfers(unsigned long data)
555 {
556 struct bfin_spi_master_data *drv_data = (struct bfin_spi_master_data *)data;
557 struct spi_message *message = NULL;
558 struct spi_transfer *transfer = NULL;
559 struct spi_transfer *previous = NULL;
560 struct bfin_spi_slave_data *chip = NULL;
561 unsigned int bits_per_word;
562 u16 cr, cr_width = 0, dma_width, dma_config;
563 u32 tranf_success = 1;
564 u8 full_duplex = 0;
565
566 /* Get current state information */
567 message = drv_data->cur_msg;
568 transfer = drv_data->cur_transfer;
569 chip = drv_data->cur_chip;
570
571 /*
572 * if msg is error or done, report it back using complete() callback
573 */
574
575 /* Handle for abort */
576 if (message->state == ERROR_STATE) {
577 dev_dbg(&drv_data->pdev->dev, "transfer: we've hit an error\n");
578 message->status = -EIO;
579 bfin_spi_giveback(drv_data);
580 return;
581 }
582
583 /* Handle end of message */
584 if (message->state == DONE_STATE) {
585 dev_dbg(&drv_data->pdev->dev, "transfer: all done!\n");
586 message->status = 0;
587 bfin_spi_flush(drv_data);
588 bfin_spi_giveback(drv_data);
589 return;
590 }
591
592 /* Delay if requested at end of transfer */
593 if (message->state == RUNNING_STATE) {
594 dev_dbg(&drv_data->pdev->dev, "transfer: still running ...\n");
595 previous = list_entry(transfer->transfer_list.prev,
596 struct spi_transfer, transfer_list);
597 if (previous->delay_usecs)
598 udelay(previous->delay_usecs);
599 }
600
601 /* Flush any existing transfers that may be sitting in the hardware */
602 if (bfin_spi_flush(drv_data) == 0) {
603 dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
604 message->status = -EIO;
605 bfin_spi_giveback(drv_data);
606 return;
607 }
608
609 if (transfer->len == 0) {
610 /* Move to next transfer of this msg */
611 message->state = bfin_spi_next_transfer(drv_data);
612 /* Schedule next transfer tasklet */
613 tasklet_schedule(&drv_data->pump_transfers);
614 return;
615 }
616
617 if (transfer->tx_buf != NULL) {
618 drv_data->tx = (void *)transfer->tx_buf;
619 drv_data->tx_end = drv_data->tx + transfer->len;
620 dev_dbg(&drv_data->pdev->dev, "tx_buf is %p, tx_end is %p\n",
621 transfer->tx_buf, drv_data->tx_end);
622 } else {
623 drv_data->tx = NULL;
624 }
625
626 if (transfer->rx_buf != NULL) {
627 full_duplex = transfer->tx_buf != NULL;
628 drv_data->rx = transfer->rx_buf;
629 drv_data->rx_end = drv_data->rx + transfer->len;
630 dev_dbg(&drv_data->pdev->dev, "rx_buf is %p, rx_end is %p\n",
631 transfer->rx_buf, drv_data->rx_end);
632 } else {
633 drv_data->rx = NULL;
634 }
635
636 drv_data->rx_dma = transfer->rx_dma;
637 drv_data->tx_dma = transfer->tx_dma;
638 drv_data->len_in_bytes = transfer->len;
639 drv_data->cs_change = transfer->cs_change;
640
641 /* Bits per word setup */
642 bits_per_word = transfer->bits_per_word;
643 if (bits_per_word == 16) {
644 drv_data->n_bytes = bits_per_word/8;
645 drv_data->len = (transfer->len) >> 1;
646 cr_width = BIT_CTL_WORDSIZE;
647 drv_data->ops = &bfin_bfin_spi_transfer_ops_u16;
648 } else if (bits_per_word == 8) {
649 drv_data->n_bytes = bits_per_word/8;
650 drv_data->len = transfer->len;
651 drv_data->ops = &bfin_bfin_spi_transfer_ops_u8;
652 }
653 cr = bfin_read(&drv_data->regs->ctl) & ~(BIT_CTL_TIMOD | BIT_CTL_WORDSIZE);
654 cr |= cr_width;
655 bfin_write(&drv_data->regs->ctl, cr);
656
657 dev_dbg(&drv_data->pdev->dev,
658 "transfer: drv_data->ops is %p, chip->ops is %p, u8_ops is %p\n",
659 drv_data->ops, chip->ops, &bfin_bfin_spi_transfer_ops_u8);
660
661 message->state = RUNNING_STATE;
662 dma_config = 0;
663
664 /* Speed setup (surely valid because already checked) */
665 if (transfer->speed_hz)
666 bfin_write(&drv_data->regs->baud, hz_to_spi_baud(transfer->speed_hz));
667 else
668 bfin_write(&drv_data->regs->baud, chip->baud);
669
670 bfin_write(&drv_data->regs->stat, BIT_STAT_CLR);
671 bfin_spi_cs_active(drv_data, chip);
672
673 dev_dbg(&drv_data->pdev->dev,
674 "now pumping a transfer: width is %d, len is %d\n",
675 cr_width, transfer->len);
676
677 /*
678 * Try to map dma buffer and do a dma transfer. If successful use,
679 * different way to r/w according to the enable_dma settings and if
680 * we are not doing a full duplex transfer (since the hardware does
681 * not support full duplex DMA transfers).
682 */
683 if (!full_duplex && drv_data->cur_chip->enable_dma
684 && drv_data->len > 6) {
685
686 unsigned long dma_start_addr, flags;
687
688 disable_dma(drv_data->dma_channel);
689 clear_dma_irqstat(drv_data->dma_channel);
690
691 /* config dma channel */
692 dev_dbg(&drv_data->pdev->dev, "doing dma transfer\n");
693 set_dma_x_count(drv_data->dma_channel, drv_data->len);
694 if (cr_width == BIT_CTL_WORDSIZE) {
695 set_dma_x_modify(drv_data->dma_channel, 2);
696 dma_width = WDSIZE_16;
697 } else {
698 set_dma_x_modify(drv_data->dma_channel, 1);
699 dma_width = WDSIZE_8;
700 }
701
702 /* poll for SPI completion before start */
703 while (!(bfin_read(&drv_data->regs->stat) & BIT_STAT_SPIF))
704 cpu_relax();
705
706 /* dirty hack for autobuffer DMA mode */
707 if (drv_data->tx_dma == 0xFFFF) {
708 dev_dbg(&drv_data->pdev->dev,
709 "doing autobuffer DMA out.\n");
710
711 /* no irq in autobuffer mode */
712 dma_config =
713 (DMAFLOW_AUTO | RESTART | dma_width | DI_EN);
714 set_dma_config(drv_data->dma_channel, dma_config);
715 set_dma_start_addr(drv_data->dma_channel,
716 (unsigned long)drv_data->tx);
717 enable_dma(drv_data->dma_channel);
718
719 /* start SPI transfer */
720 bfin_write(&drv_data->regs->ctl, cr | BIT_CTL_TIMOD_DMA_TX);
721
722 /* just return here, there can only be one transfer
723 * in this mode
724 */
725 message->status = 0;
726 bfin_spi_giveback(drv_data);
727 return;
728 }
729
730 /* In dma mode, rx or tx must be NULL in one transfer */
731 dma_config = (RESTART | dma_width | DI_EN);
732 if (drv_data->rx != NULL) {
733 /* set transfer mode, and enable SPI */
734 dev_dbg(&drv_data->pdev->dev, "doing DMA in to %p (size %zx)\n",
735 drv_data->rx, drv_data->len_in_bytes);
736
737 /* invalidate caches, if needed */
738 if (bfin_addr_dcacheable((unsigned long) drv_data->rx))
739 invalidate_dcache_range((unsigned long) drv_data->rx,
740 (unsigned long) (drv_data->rx +
741 drv_data->len_in_bytes));
742
743 dma_config |= WNR;
744 dma_start_addr = (unsigned long)drv_data->rx;
745 cr |= BIT_CTL_TIMOD_DMA_RX | BIT_CTL_SENDOPT;
746
747 } else if (drv_data->tx != NULL) {
748 dev_dbg(&drv_data->pdev->dev, "doing DMA out.\n");
749
750 /* flush caches, if needed */
751 if (bfin_addr_dcacheable((unsigned long) drv_data->tx))
752 flush_dcache_range((unsigned long) drv_data->tx,
753 (unsigned long) (drv_data->tx +
754 drv_data->len_in_bytes));
755
756 dma_start_addr = (unsigned long)drv_data->tx;
757 cr |= BIT_CTL_TIMOD_DMA_TX;
758
759 } else
760 BUG();
761
762 /* oh man, here there be monsters ... and i dont mean the
763 * fluffy cute ones from pixar, i mean the kind that'll eat
764 * your data, kick your dog, and love it all. do *not* try
765 * and change these lines unless you (1) heavily test DMA
766 * with SPI flashes on a loaded system (e.g. ping floods),
767 * (2) know just how broken the DMA engine interaction with
768 * the SPI peripheral is, and (3) have someone else to blame
769 * when you screw it all up anyways.
770 */
771 set_dma_start_addr(drv_data->dma_channel, dma_start_addr);
772 set_dma_config(drv_data->dma_channel, dma_config);
773 local_irq_save(flags);
774 SSYNC();
775 bfin_write(&drv_data->regs->ctl, cr);
776 enable_dma(drv_data->dma_channel);
777 dma_enable_irq(drv_data->dma_channel);
778 local_irq_restore(flags);
779
780 return;
781 }
782
783 /*
784 * We always use SPI_WRITE mode (transfer starts with TDBR write).
785 * SPI_READ mode (transfer starts with RDBR read) seems to have
786 * problems with setting up the output value in TDBR prior to the
787 * start of the transfer.
788 */
789 bfin_write(&drv_data->regs->ctl, cr | BIT_CTL_TXMOD);
790
791 if (chip->pio_interrupt) {
792 /* SPI irq should have been disabled by now */
793
794 /* discard old RX data and clear RXS */
795 bfin_spi_dummy_read(drv_data);
796
797 /* start transfer */
798 if (drv_data->tx == NULL)
799 bfin_write(&drv_data->regs->tdbr, chip->idle_tx_val);
800 else {
801 int loop;
802 if (bits_per_word == 16) {
803 u16 *buf = (u16 *)drv_data->tx;
804 for (loop = 0; loop < bits_per_word / 16;
805 loop++) {
806 bfin_write(&drv_data->regs->tdbr, *buf++);
807 }
808 } else if (bits_per_word == 8) {
809 u8 *buf = (u8 *)drv_data->tx;
810 for (loop = 0; loop < bits_per_word / 8; loop++)
811 bfin_write(&drv_data->regs->tdbr, *buf++);
812 }
813
814 drv_data->tx += drv_data->n_bytes;
815 }
816
817 /* once TDBR is empty, interrupt is triggered */
818 enable_irq(drv_data->spi_irq);
819 return;
820 }
821
822 /* IO mode */
823 dev_dbg(&drv_data->pdev->dev, "doing IO transfer\n");
824
825 if (full_duplex) {
826 /* full duplex mode */
827 BUG_ON((drv_data->tx_end - drv_data->tx) !=
828 (drv_data->rx_end - drv_data->rx));
829 dev_dbg(&drv_data->pdev->dev,
830 "IO duplex: cr is 0x%x\n", cr);
831
832 drv_data->ops->duplex(drv_data);
833
834 if (drv_data->tx != drv_data->tx_end)
835 tranf_success = 0;
836 } else if (drv_data->tx != NULL) {
837 /* write only half duplex */
838 dev_dbg(&drv_data->pdev->dev,
839 "IO write: cr is 0x%x\n", cr);
840
841 drv_data->ops->write(drv_data);
842
843 if (drv_data->tx != drv_data->tx_end)
844 tranf_success = 0;
845 } else if (drv_data->rx != NULL) {
846 /* read only half duplex */
847 dev_dbg(&drv_data->pdev->dev,
848 "IO read: cr is 0x%x\n", cr);
849
850 drv_data->ops->read(drv_data);
851 if (drv_data->rx != drv_data->rx_end)
852 tranf_success = 0;
853 }
854
855 if (!tranf_success) {
856 dev_dbg(&drv_data->pdev->dev,
857 "IO write error!\n");
858 message->state = ERROR_STATE;
859 } else {
860 /* Update total byte transferred */
861 message->actual_length += drv_data->len_in_bytes;
862 /* Move to next transfer of this msg */
863 message->state = bfin_spi_next_transfer(drv_data);
864 if (drv_data->cs_change && message->state != DONE_STATE) {
865 bfin_spi_flush(drv_data);
866 bfin_spi_cs_deactive(drv_data, chip);
867 }
868 }
869
870 /* Schedule next transfer tasklet */
871 tasklet_schedule(&drv_data->pump_transfers);
872 }
873
874 /* pop a msg from queue and kick off real transfer */
875 static void bfin_spi_pump_messages(struct work_struct *work)
876 {
877 struct bfin_spi_master_data *drv_data;
878 unsigned long flags;
879
880 drv_data = container_of(work, struct bfin_spi_master_data, pump_messages);
881
882 /* Lock queue and check for queue work */
883 spin_lock_irqsave(&drv_data->lock, flags);
884 if (list_empty(&drv_data->queue) || !drv_data->running) {
885 /* pumper kicked off but no work to do */
886 drv_data->busy = 0;
887 spin_unlock_irqrestore(&drv_data->lock, flags);
888 return;
889 }
890
891 /* Make sure we are not already running a message */
892 if (drv_data->cur_msg) {
893 spin_unlock_irqrestore(&drv_data->lock, flags);
894 return;
895 }
896
897 /* Extract head of queue */
898 drv_data->cur_msg = list_entry(drv_data->queue.next,
899 struct spi_message, queue);
900
901 /* Setup the SSP using the per chip configuration */
902 drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
903 bfin_spi_restore_state(drv_data);
904
905 list_del_init(&drv_data->cur_msg->queue);
906
907 /* Initial message state */
908 drv_data->cur_msg->state = START_STATE;
909 drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
910 struct spi_transfer, transfer_list);
911
912 dev_dbg(&drv_data->pdev->dev,
913 "got a message to pump, state is set to: baud "
914 "%d, flag 0x%x, ctl 0x%x\n",
915 drv_data->cur_chip->baud, drv_data->cur_chip->flag,
916 drv_data->cur_chip->ctl_reg);
917
918 dev_dbg(&drv_data->pdev->dev,
919 "the first transfer len is %d\n",
920 drv_data->cur_transfer->len);
921
922 /* Mark as busy and launch transfers */
923 tasklet_schedule(&drv_data->pump_transfers);
924
925 drv_data->busy = 1;
926 spin_unlock_irqrestore(&drv_data->lock, flags);
927 }
928
929 /*
930 * got a msg to transfer, queue it in drv_data->queue.
931 * And kick off message pumper
932 */
933 static int bfin_spi_transfer(struct spi_device *spi, struct spi_message *msg)
934 {
935 struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
936 unsigned long flags;
937
938 spin_lock_irqsave(&drv_data->lock, flags);
939
940 if (!drv_data->running) {
941 spin_unlock_irqrestore(&drv_data->lock, flags);
942 return -ESHUTDOWN;
943 }
944
945 msg->actual_length = 0;
946 msg->status = -EINPROGRESS;
947 msg->state = START_STATE;
948
949 dev_dbg(&spi->dev, "adding an msg in transfer() \n");
950 list_add_tail(&msg->queue, &drv_data->queue);
951
952 if (drv_data->running && !drv_data->busy)
953 queue_work(drv_data->workqueue, &drv_data->pump_messages);
954
955 spin_unlock_irqrestore(&drv_data->lock, flags);
956
957 return 0;
958 }
959
960 #define MAX_SPI_SSEL 7
961
962 static const u16 ssel[][MAX_SPI_SSEL] = {
963 {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
964 P_SPI0_SSEL4, P_SPI0_SSEL5,
965 P_SPI0_SSEL6, P_SPI0_SSEL7},
966
967 {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
968 P_SPI1_SSEL4, P_SPI1_SSEL5,
969 P_SPI1_SSEL6, P_SPI1_SSEL7},
970
971 {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
972 P_SPI2_SSEL4, P_SPI2_SSEL5,
973 P_SPI2_SSEL6, P_SPI2_SSEL7},
974 };
975
976 /* setup for devices (may be called multiple times -- not just first setup) */
977 static int bfin_spi_setup(struct spi_device *spi)
978 {
979 struct bfin5xx_spi_chip *chip_info;
980 struct bfin_spi_slave_data *chip = NULL;
981 struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
982 u16 bfin_ctl_reg;
983 int ret = -EINVAL;
984
985 /* Only alloc (or use chip_info) on first setup */
986 chip_info = NULL;
987 chip = spi_get_ctldata(spi);
988 if (chip == NULL) {
989 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
990 if (!chip) {
991 dev_err(&spi->dev, "cannot allocate chip data\n");
992 ret = -ENOMEM;
993 goto error;
994 }
995
996 chip->enable_dma = 0;
997 chip_info = spi->controller_data;
998 }
999
1000 /* Let people set non-standard bits directly */
1001 bfin_ctl_reg = BIT_CTL_OPENDRAIN | BIT_CTL_EMISO |
1002 BIT_CTL_PSSE | BIT_CTL_GM | BIT_CTL_SZ;
1003
1004 /* chip_info isn't always needed */
1005 if (chip_info) {
1006 /* Make sure people stop trying to set fields via ctl_reg
1007 * when they should actually be using common SPI framework.
1008 * Currently we let through: WOM EMISO PSSE GM SZ.
1009 * Not sure if a user actually needs/uses any of these,
1010 * but let's assume (for now) they do.
1011 */
1012 if (chip_info->ctl_reg & ~bfin_ctl_reg) {
1013 dev_err(&spi->dev,
1014 "do not set bits in ctl_reg that the SPI framework manages\n");
1015 goto error;
1016 }
1017 chip->enable_dma = chip_info->enable_dma != 0
1018 && drv_data->master_info->enable_dma;
1019 chip->ctl_reg = chip_info->ctl_reg;
1020 chip->cs_chg_udelay = chip_info->cs_chg_udelay;
1021 chip->idle_tx_val = chip_info->idle_tx_val;
1022 chip->pio_interrupt = chip_info->pio_interrupt;
1023 } else {
1024 /* force a default base state */
1025 chip->ctl_reg &= bfin_ctl_reg;
1026 }
1027
1028 /* translate common spi framework into our register */
1029 if (spi->mode & SPI_CPOL)
1030 chip->ctl_reg |= BIT_CTL_CPOL;
1031 if (spi->mode & SPI_CPHA)
1032 chip->ctl_reg |= BIT_CTL_CPHA;
1033 if (spi->mode & SPI_LSB_FIRST)
1034 chip->ctl_reg |= BIT_CTL_LSBF;
1035 /* we dont support running in slave mode (yet?) */
1036 chip->ctl_reg |= BIT_CTL_MASTER;
1037
1038 /*
1039 * Notice: for blackfin, the speed_hz is the value of register
1040 * SPI_BAUD, not the real baudrate
1041 */
1042 chip->baud = hz_to_spi_baud(spi->max_speed_hz);
1043 chip->chip_select_num = spi->chip_select;
1044 if (chip->chip_select_num < MAX_CTRL_CS) {
1045 if (!(spi->mode & SPI_CPHA))
1046 dev_warn(&spi->dev,
1047 "Warning: SPI CPHA not set: Slave Select not under software control!\n"
1048 "See Documentation/blackfin/bfin-spi-notes.txt\n");
1049
1050 chip->flag = (1 << spi->chip_select) << 8;
1051 } else
1052 chip->cs_gpio = chip->chip_select_num - MAX_CTRL_CS;
1053
1054 if (chip->enable_dma && chip->pio_interrupt) {
1055 dev_err(&spi->dev,
1056 "enable_dma is set, do not set pio_interrupt\n");
1057 goto error;
1058 }
1059 /*
1060 * if any one SPI chip is registered and wants DMA, request the
1061 * DMA channel for it
1062 */
1063 if (chip->enable_dma && !drv_data->dma_requested) {
1064 /* register dma irq handler */
1065 ret = request_dma(drv_data->dma_channel, "BFIN_SPI_DMA");
1066 if (ret) {
1067 dev_err(&spi->dev,
1068 "Unable to request BlackFin SPI DMA channel\n");
1069 goto error;
1070 }
1071 drv_data->dma_requested = 1;
1072
1073 ret = set_dma_callback(drv_data->dma_channel,
1074 bfin_spi_dma_irq_handler, drv_data);
1075 if (ret) {
1076 dev_err(&spi->dev, "Unable to set dma callback\n");
1077 goto error;
1078 }
1079 dma_disable_irq(drv_data->dma_channel);
1080 }
1081
1082 if (chip->pio_interrupt && !drv_data->irq_requested) {
1083 ret = request_irq(drv_data->spi_irq, bfin_spi_pio_irq_handler,
1084 0, "BFIN_SPI", drv_data);
1085 if (ret) {
1086 dev_err(&spi->dev, "Unable to register spi IRQ\n");
1087 goto error;
1088 }
1089 drv_data->irq_requested = 1;
1090 /* we use write mode, spi irq has to be disabled here */
1091 disable_irq(drv_data->spi_irq);
1092 }
1093
1094 if (chip->chip_select_num >= MAX_CTRL_CS) {
1095 /* Only request on first setup */
1096 if (spi_get_ctldata(spi) == NULL) {
1097 ret = gpio_request(chip->cs_gpio, spi->modalias);
1098 if (ret) {
1099 dev_err(&spi->dev, "gpio_request() error\n");
1100 goto pin_error;
1101 }
1102 gpio_direction_output(chip->cs_gpio, 1);
1103 }
1104 }
1105
1106 dev_dbg(&spi->dev, "setup spi chip %s, width is %d, dma is %d\n",
1107 spi->modalias, spi->bits_per_word, chip->enable_dma);
1108 dev_dbg(&spi->dev, "ctl_reg is 0x%x, flag_reg is 0x%x\n",
1109 chip->ctl_reg, chip->flag);
1110
1111 spi_set_ctldata(spi, chip);
1112
1113 dev_dbg(&spi->dev, "chip select number is %d\n", chip->chip_select_num);
1114 if (chip->chip_select_num < MAX_CTRL_CS) {
1115 ret = peripheral_request(ssel[spi->master->bus_num]
1116 [chip->chip_select_num-1], spi->modalias);
1117 if (ret) {
1118 dev_err(&spi->dev, "peripheral_request() error\n");
1119 goto pin_error;
1120 }
1121 }
1122
1123 bfin_spi_cs_enable(drv_data, chip);
1124 bfin_spi_cs_deactive(drv_data, chip);
1125
1126 return 0;
1127
1128 pin_error:
1129 if (chip->chip_select_num >= MAX_CTRL_CS)
1130 gpio_free(chip->cs_gpio);
1131 else
1132 peripheral_free(ssel[spi->master->bus_num]
1133 [chip->chip_select_num - 1]);
1134 error:
1135 if (chip) {
1136 if (drv_data->dma_requested)
1137 free_dma(drv_data->dma_channel);
1138 drv_data->dma_requested = 0;
1139
1140 kfree(chip);
1141 /* prevent free 'chip' twice */
1142 spi_set_ctldata(spi, NULL);
1143 }
1144
1145 return ret;
1146 }
1147
1148 /*
1149 * callback for spi framework.
1150 * clean driver specific data
1151 */
1152 static void bfin_spi_cleanup(struct spi_device *spi)
1153 {
1154 struct bfin_spi_slave_data *chip = spi_get_ctldata(spi);
1155 struct bfin_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
1156
1157 if (!chip)
1158 return;
1159
1160 if (chip->chip_select_num < MAX_CTRL_CS) {
1161 peripheral_free(ssel[spi->master->bus_num]
1162 [chip->chip_select_num-1]);
1163 bfin_spi_cs_disable(drv_data, chip);
1164 } else
1165 gpio_free(chip->cs_gpio);
1166
1167 kfree(chip);
1168 /* prevent free 'chip' twice */
1169 spi_set_ctldata(spi, NULL);
1170 }
1171
1172 static int bfin_spi_init_queue(struct bfin_spi_master_data *drv_data)
1173 {
1174 INIT_LIST_HEAD(&drv_data->queue);
1175 spin_lock_init(&drv_data->lock);
1176
1177 drv_data->running = false;
1178 drv_data->busy = 0;
1179
1180 /* init transfer tasklet */
1181 tasklet_init(&drv_data->pump_transfers,
1182 bfin_spi_pump_transfers, (unsigned long)drv_data);
1183
1184 /* init messages workqueue */
1185 INIT_WORK(&drv_data->pump_messages, bfin_spi_pump_messages);
1186 drv_data->workqueue = create_singlethread_workqueue(
1187 dev_name(drv_data->master->dev.parent));
1188 if (drv_data->workqueue == NULL)
1189 return -EBUSY;
1190
1191 return 0;
1192 }
1193
1194 static int bfin_spi_start_queue(struct bfin_spi_master_data *drv_data)
1195 {
1196 unsigned long flags;
1197
1198 spin_lock_irqsave(&drv_data->lock, flags);
1199
1200 if (drv_data->running || drv_data->busy) {
1201 spin_unlock_irqrestore(&drv_data->lock, flags);
1202 return -EBUSY;
1203 }
1204
1205 drv_data->running = true;
1206 drv_data->cur_msg = NULL;
1207 drv_data->cur_transfer = NULL;
1208 drv_data->cur_chip = NULL;
1209 spin_unlock_irqrestore(&drv_data->lock, flags);
1210
1211 queue_work(drv_data->workqueue, &drv_data->pump_messages);
1212
1213 return 0;
1214 }
1215
1216 static int bfin_spi_stop_queue(struct bfin_spi_master_data *drv_data)
1217 {
1218 unsigned long flags;
1219 unsigned limit = 500;
1220 int status = 0;
1221
1222 spin_lock_irqsave(&drv_data->lock, flags);
1223
1224 /*
1225 * This is a bit lame, but is optimized for the common execution path.
1226 * A wait_queue on the drv_data->busy could be used, but then the common
1227 * execution path (pump_messages) would be required to call wake_up or
1228 * friends on every SPI message. Do this instead
1229 */
1230 drv_data->running = false;
1231 while ((!list_empty(&drv_data->queue) || drv_data->busy) && limit--) {
1232 spin_unlock_irqrestore(&drv_data->lock, flags);
1233 msleep(10);
1234 spin_lock_irqsave(&drv_data->lock, flags);
1235 }
1236
1237 if (!list_empty(&drv_data->queue) || drv_data->busy)
1238 status = -EBUSY;
1239
1240 spin_unlock_irqrestore(&drv_data->lock, flags);
1241
1242 return status;
1243 }
1244
1245 static int bfin_spi_destroy_queue(struct bfin_spi_master_data *drv_data)
1246 {
1247 int status;
1248
1249 status = bfin_spi_stop_queue(drv_data);
1250 if (status != 0)
1251 return status;
1252
1253 destroy_workqueue(drv_data->workqueue);
1254
1255 return 0;
1256 }
1257
1258 static int bfin_spi_probe(struct platform_device *pdev)
1259 {
1260 struct device *dev = &pdev->dev;
1261 struct bfin5xx_spi_master *platform_info;
1262 struct spi_master *master;
1263 struct bfin_spi_master_data *drv_data;
1264 struct resource *res;
1265 int status = 0;
1266
1267 platform_info = dev_get_platdata(dev);
1268
1269 /* Allocate master with space for drv_data */
1270 master = spi_alloc_master(dev, sizeof(*drv_data));
1271 if (!master) {
1272 dev_err(&pdev->dev, "can not alloc spi_master\n");
1273 return -ENOMEM;
1274 }
1275
1276 drv_data = spi_master_get_devdata(master);
1277 drv_data->master = master;
1278 drv_data->master_info = platform_info;
1279 drv_data->pdev = pdev;
1280 drv_data->pin_req = platform_info->pin_req;
1281
1282 /* the spi->mode bits supported by this driver: */
1283 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1284 master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
1285 master->bus_num = pdev->id;
1286 master->num_chipselect = platform_info->num_chipselect;
1287 master->cleanup = bfin_spi_cleanup;
1288 master->setup = bfin_spi_setup;
1289 master->transfer = bfin_spi_transfer;
1290
1291 /* Find and map our resources */
1292 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1293 if (res == NULL) {
1294 dev_err(dev, "Cannot get IORESOURCE_MEM\n");
1295 status = -ENOENT;
1296 goto out_error_get_res;
1297 }
1298
1299 drv_data->regs = ioremap(res->start, resource_size(res));
1300 if (drv_data->regs == NULL) {
1301 dev_err(dev, "Cannot map IO\n");
1302 status = -ENXIO;
1303 goto out_error_ioremap;
1304 }
1305
1306 res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1307 if (res == NULL) {
1308 dev_err(dev, "No DMA channel specified\n");
1309 status = -ENOENT;
1310 goto out_error_free_io;
1311 }
1312 drv_data->dma_channel = res->start;
1313
1314 drv_data->spi_irq = platform_get_irq(pdev, 0);
1315 if (drv_data->spi_irq < 0) {
1316 dev_err(dev, "No spi pio irq specified\n");
1317 status = -ENOENT;
1318 goto out_error_free_io;
1319 }
1320
1321 /* Initial and start queue */
1322 status = bfin_spi_init_queue(drv_data);
1323 if (status != 0) {
1324 dev_err(dev, "problem initializing queue\n");
1325 goto out_error_queue_alloc;
1326 }
1327
1328 status = bfin_spi_start_queue(drv_data);
1329 if (status != 0) {
1330 dev_err(dev, "problem starting queue\n");
1331 goto out_error_queue_alloc;
1332 }
1333
1334 status = peripheral_request_list(drv_data->pin_req, DRV_NAME);
1335 if (status != 0) {
1336 dev_err(&pdev->dev, ": Requesting Peripherals failed\n");
1337 goto out_error_queue_alloc;
1338 }
1339
1340 /* Reset SPI registers. If these registers were used by the boot loader,
1341 * the sky may fall on your head if you enable the dma controller.
1342 */
1343 bfin_write(&drv_data->regs->ctl, BIT_CTL_CPHA | BIT_CTL_MASTER);
1344 bfin_write(&drv_data->regs->flg, 0xFF00);
1345
1346 /* Register with the SPI framework */
1347 platform_set_drvdata(pdev, drv_data);
1348 status = spi_register_master(master);
1349 if (status != 0) {
1350 dev_err(dev, "problem registering spi master\n");
1351 goto out_error_queue_alloc;
1352 }
1353
1354 dev_info(dev, "%s, Version %s, regs@%p, dma channel@%d\n",
1355 DRV_DESC, DRV_VERSION, drv_data->regs,
1356 drv_data->dma_channel);
1357 return status;
1358
1359 out_error_queue_alloc:
1360 bfin_spi_destroy_queue(drv_data);
1361 out_error_free_io:
1362 iounmap(drv_data->regs);
1363 out_error_ioremap:
1364 out_error_get_res:
1365 spi_master_put(master);
1366
1367 return status;
1368 }
1369
1370 /* stop hardware and remove the driver */
1371 static int bfin_spi_remove(struct platform_device *pdev)
1372 {
1373 struct bfin_spi_master_data *drv_data = platform_get_drvdata(pdev);
1374 int status = 0;
1375
1376 if (!drv_data)
1377 return 0;
1378
1379 /* Remove the queue */
1380 status = bfin_spi_destroy_queue(drv_data);
1381 if (status != 0)
1382 return status;
1383
1384 /* Disable the SSP at the peripheral and SOC level */
1385 bfin_spi_disable(drv_data);
1386
1387 /* Release DMA */
1388 if (drv_data->master_info->enable_dma) {
1389 if (dma_channel_active(drv_data->dma_channel))
1390 free_dma(drv_data->dma_channel);
1391 }
1392
1393 if (drv_data->irq_requested) {
1394 free_irq(drv_data->spi_irq, drv_data);
1395 drv_data->irq_requested = 0;
1396 }
1397
1398 /* Disconnect from the SPI framework */
1399 spi_unregister_master(drv_data->master);
1400
1401 peripheral_free_list(drv_data->pin_req);
1402
1403 return 0;
1404 }
1405
1406 #ifdef CONFIG_PM_SLEEP
1407 static int bfin_spi_suspend(struct device *dev)
1408 {
1409 struct bfin_spi_master_data *drv_data = dev_get_drvdata(dev);
1410 int status = 0;
1411
1412 status = bfin_spi_stop_queue(drv_data);
1413 if (status != 0)
1414 return status;
1415
1416 drv_data->ctrl_reg = bfin_read(&drv_data->regs->ctl);
1417 drv_data->flag_reg = bfin_read(&drv_data->regs->flg);
1418
1419 /*
1420 * reset SPI_CTL and SPI_FLG registers
1421 */
1422 bfin_write(&drv_data->regs->ctl, BIT_CTL_CPHA | BIT_CTL_MASTER);
1423 bfin_write(&drv_data->regs->flg, 0xFF00);
1424
1425 return 0;
1426 }
1427
1428 static int bfin_spi_resume(struct device *dev)
1429 {
1430 struct bfin_spi_master_data *drv_data = dev_get_drvdata(dev);
1431 int status = 0;
1432
1433 bfin_write(&drv_data->regs->ctl, drv_data->ctrl_reg);
1434 bfin_write(&drv_data->regs->flg, drv_data->flag_reg);
1435
1436 /* Start the queue running */
1437 status = bfin_spi_start_queue(drv_data);
1438 if (status != 0) {
1439 dev_err(dev, "problem starting queue (%d)\n", status);
1440 return status;
1441 }
1442
1443 return 0;
1444 }
1445
1446 static SIMPLE_DEV_PM_OPS(bfin_spi_pm_ops, bfin_spi_suspend, bfin_spi_resume);
1447
1448 #define BFIN_SPI_PM_OPS (&bfin_spi_pm_ops)
1449 #else
1450 #define BFIN_SPI_PM_OPS NULL
1451 #endif
1452
1453 MODULE_ALIAS("platform:bfin-spi");
1454 static struct platform_driver bfin_spi_driver = {
1455 .driver = {
1456 .name = DRV_NAME,
1457 .pm = BFIN_SPI_PM_OPS,
1458 },
1459 .probe = bfin_spi_probe,
1460 .remove = bfin_spi_remove,
1461 };
1462
1463 static int __init bfin_spi_init(void)
1464 {
1465 return platform_driver_register(&bfin_spi_driver);
1466 }
1467 subsys_initcall(bfin_spi_init);
1468
1469 static void __exit bfin_spi_exit(void)
1470 {
1471 platform_driver_unregister(&bfin_spi_driver);
1472 }
1473 module_exit(bfin_spi_exit);
Linux with added FPC-III support