blob: 902f2fb902db8c94ee238b456480a18432c644ee [file] [log] [blame]
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +09001/*
2 * SH RSPI driver
3 *
4 * Copyright (C) 2012 Renesas Solutions Corp.
5 *
6 * Based on spi-sh.c:
7 * Copyright (C) 2011 Renesas Solutions Corp.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23
24#include <linux/module.h>
25#include <linux/kernel.h>
26#include <linux/sched.h>
27#include <linux/errno.h>
28#include <linux/list.h>
29#include <linux/workqueue.h>
30#include <linux/interrupt.h>
31#include <linux/platform_device.h>
32#include <linux/io.h>
33#include <linux/clk.h>
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +090034#include <linux/dmaengine.h>
35#include <linux/dma-mapping.h>
36#include <linux/sh_dma.h>
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +090037#include <linux/spi/spi.h>
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +090038#include <linux/spi/rspi.h>
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +090039
40#define RSPI_SPCR 0x00
41#define RSPI_SSLP 0x01
42#define RSPI_SPPCR 0x02
43#define RSPI_SPSR 0x03
44#define RSPI_SPDR 0x04
45#define RSPI_SPSCR 0x08
46#define RSPI_SPSSR 0x09
47#define RSPI_SPBR 0x0a
48#define RSPI_SPDCR 0x0b
49#define RSPI_SPCKD 0x0c
50#define RSPI_SSLND 0x0d
51#define RSPI_SPND 0x0e
52#define RSPI_SPCR2 0x0f
53#define RSPI_SPCMD0 0x10
54#define RSPI_SPCMD1 0x12
55#define RSPI_SPCMD2 0x14
56#define RSPI_SPCMD3 0x16
57#define RSPI_SPCMD4 0x18
58#define RSPI_SPCMD5 0x1a
59#define RSPI_SPCMD6 0x1c
60#define RSPI_SPCMD7 0x1e
61
62/* SPCR */
63#define SPCR_SPRIE 0x80
64#define SPCR_SPE 0x40
65#define SPCR_SPTIE 0x20
66#define SPCR_SPEIE 0x10
67#define SPCR_MSTR 0x08
68#define SPCR_MODFEN 0x04
69#define SPCR_TXMD 0x02
70#define SPCR_SPMS 0x01
71
72/* SSLP */
73#define SSLP_SSL1P 0x02
74#define SSLP_SSL0P 0x01
75
76/* SPPCR */
77#define SPPCR_MOIFE 0x20
78#define SPPCR_MOIFV 0x10
79#define SPPCR_SPOM 0x04
80#define SPPCR_SPLP2 0x02
81#define SPPCR_SPLP 0x01
82
83/* SPSR */
84#define SPSR_SPRF 0x80
85#define SPSR_SPTEF 0x20
86#define SPSR_PERF 0x08
87#define SPSR_MODF 0x04
88#define SPSR_IDLNF 0x02
89#define SPSR_OVRF 0x01
90
91/* SPSCR */
92#define SPSCR_SPSLN_MASK 0x07
93
94/* SPSSR */
95#define SPSSR_SPECM_MASK 0x70
96#define SPSSR_SPCP_MASK 0x07
97
98/* SPDCR */
99#define SPDCR_SPLW 0x20
100#define SPDCR_SPRDTD 0x10
101#define SPDCR_SLSEL1 0x08
102#define SPDCR_SLSEL0 0x04
103#define SPDCR_SLSEL_MASK 0x0c
104#define SPDCR_SPFC1 0x02
105#define SPDCR_SPFC0 0x01
106
107/* SPCKD */
108#define SPCKD_SCKDL_MASK 0x07
109
110/* SSLND */
111#define SSLND_SLNDL_MASK 0x07
112
113/* SPND */
114#define SPND_SPNDL_MASK 0x07
115
116/* SPCR2 */
117#define SPCR2_PTE 0x08
118#define SPCR2_SPIE 0x04
119#define SPCR2_SPOE 0x02
120#define SPCR2_SPPE 0x01
121
122/* SPCMDn */
123#define SPCMD_SCKDEN 0x8000
124#define SPCMD_SLNDEN 0x4000
125#define SPCMD_SPNDEN 0x2000
126#define SPCMD_LSBF 0x1000
127#define SPCMD_SPB_MASK 0x0f00
128#define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK)
129#define SPCMD_SPB_20BIT 0x0000
130#define SPCMD_SPB_24BIT 0x0100
131#define SPCMD_SPB_32BIT 0x0200
132#define SPCMD_SSLKP 0x0080
133#define SPCMD_SSLA_MASK 0x0030
134#define SPCMD_BRDV_MASK 0x000c
135#define SPCMD_CPOL 0x0002
136#define SPCMD_CPHA 0x0001
137
138struct rspi_data {
139 void __iomem *addr;
140 u32 max_speed_hz;
141 struct spi_master *master;
142 struct list_head queue;
143 struct work_struct ws;
144 wait_queue_head_t wait;
145 spinlock_t lock;
146 struct clk *clk;
147 unsigned char spsr;
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900148
149 /* for dmaengine */
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900150 struct dma_chan *chan_tx;
151 struct dma_chan *chan_rx;
152 int irq;
153
154 unsigned dma_width_16bit:1;
155 unsigned dma_callbacked:1;
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900156};
157
158static void rspi_write8(struct rspi_data *rspi, u8 data, u16 offset)
159{
160 iowrite8(data, rspi->addr + offset);
161}
162
163static void rspi_write16(struct rspi_data *rspi, u16 data, u16 offset)
164{
165 iowrite16(data, rspi->addr + offset);
166}
167
168static u8 rspi_read8(struct rspi_data *rspi, u16 offset)
169{
170 return ioread8(rspi->addr + offset);
171}
172
173static u16 rspi_read16(struct rspi_data *rspi, u16 offset)
174{
175 return ioread16(rspi->addr + offset);
176}
177
178static unsigned char rspi_calc_spbr(struct rspi_data *rspi)
179{
180 int tmp;
181 unsigned char spbr;
182
183 tmp = clk_get_rate(rspi->clk) / (2 * rspi->max_speed_hz) - 1;
184 spbr = clamp(tmp, 0, 255);
185
186 return spbr;
187}
188
189static void rspi_enable_irq(struct rspi_data *rspi, u8 enable)
190{
191 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR);
192}
193
194static void rspi_disable_irq(struct rspi_data *rspi, u8 disable)
195{
196 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR);
197}
198
199static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask,
200 u8 enable_bit)
201{
202 int ret;
203
204 rspi->spsr = rspi_read8(rspi, RSPI_SPSR);
205 rspi_enable_irq(rspi, enable_bit);
206 ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ);
207 if (ret == 0 && !(rspi->spsr & wait_mask))
208 return -ETIMEDOUT;
209
210 return 0;
211}
212
213static void rspi_assert_ssl(struct rspi_data *rspi)
214{
215 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR);
216}
217
218static void rspi_negate_ssl(struct rspi_data *rspi)
219{
220 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR);
221}
222
223static int rspi_set_config_register(struct rspi_data *rspi, int access_size)
224{
225 /* Sets output mode(CMOS) and MOSI signal(from previous transfer) */
226 rspi_write8(rspi, 0x00, RSPI_SPPCR);
227
228 /* Sets transfer bit rate */
229 rspi_write8(rspi, rspi_calc_spbr(rspi), RSPI_SPBR);
230
231 /* Sets number of frames to be used: 1 frame */
232 rspi_write8(rspi, 0x00, RSPI_SPDCR);
233
234 /* Sets RSPCK, SSL, next-access delay value */
235 rspi_write8(rspi, 0x00, RSPI_SPCKD);
236 rspi_write8(rspi, 0x00, RSPI_SSLND);
237 rspi_write8(rspi, 0x00, RSPI_SPND);
238
239 /* Sets parity, interrupt mask */
240 rspi_write8(rspi, 0x00, RSPI_SPCR2);
241
242 /* Sets SPCMD */
243 rspi_write16(rspi, SPCMD_SPB_8_TO_16(access_size) | SPCMD_SSLKP,
244 RSPI_SPCMD0);
245
246 /* Sets RSPI mode */
247 rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR);
248
249 return 0;
250}
251
252static int rspi_send_pio(struct rspi_data *rspi, struct spi_message *mesg,
253 struct spi_transfer *t)
254{
255 int remain = t->len;
256 u8 *data;
257
258 data = (u8 *)t->tx_buf;
259 while (remain > 0) {
260 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD,
261 RSPI_SPCR);
262
263 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
264 dev_err(&rspi->master->dev,
265 "%s: tx empty timeout\n", __func__);
266 return -ETIMEDOUT;
267 }
268
269 rspi_write16(rspi, *data, RSPI_SPDR);
270 data++;
271 remain--;
272 }
273
274 /* Waiting for the last transmition */
275 rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE);
276
277 return 0;
278}
279
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900280static void rspi_dma_complete(void *arg)
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900281{
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900282 struct rspi_data *rspi = arg;
283
284 rspi->dma_callbacked = 1;
285 wake_up_interruptible(&rspi->wait);
286}
287
288static int rspi_dma_map_sg(struct scatterlist *sg, void *buf, unsigned len,
289 struct dma_chan *chan,
290 enum dma_transfer_direction dir)
291{
292 sg_init_table(sg, 1);
293 sg_set_buf(sg, buf, len);
294 sg_dma_len(sg) = len;
295 return dma_map_sg(chan->device->dev, sg, 1, dir);
296}
297
298static void rspi_dma_unmap_sg(struct scatterlist *sg, struct dma_chan *chan,
299 enum dma_transfer_direction dir)
300{
301 dma_unmap_sg(chan->device->dev, sg, 1, dir);
302}
303
304static void rspi_memory_to_8bit(void *buf, const void *data, unsigned len)
305{
306 u16 *dst = buf;
307 const u8 *src = data;
308
309 while (len) {
310 *dst++ = (u16)(*src++);
311 len--;
312 }
313}
314
315static void rspi_memory_from_8bit(void *buf, const void *data, unsigned len)
316{
317 u8 *dst = buf;
318 const u16 *src = data;
319
320 while (len) {
321 *dst++ = (u8)*src++;
322 len--;
323 }
324}
325
326static int rspi_send_dma(struct rspi_data *rspi, struct spi_transfer *t)
327{
328 struct scatterlist sg;
329 void *buf = NULL;
330 struct dma_async_tx_descriptor *desc;
331 unsigned len;
332 int ret = 0;
333
334 if (rspi->dma_width_16bit) {
335 /*
336 * If DMAC bus width is 16-bit, the driver allocates a dummy
337 * buffer. And, the driver converts original data into the
338 * DMAC data as the following format:
339 * original data: 1st byte, 2nd byte ...
340 * DMAC data: 1st byte, dummy, 2nd byte, dummy ...
341 */
342 len = t->len * 2;
343 buf = kmalloc(len, GFP_KERNEL);
344 if (!buf)
345 return -ENOMEM;
346 rspi_memory_to_8bit(buf, t->tx_buf, t->len);
347 } else {
348 len = t->len;
349 buf = (void *)t->tx_buf;
350 }
351
352 if (!rspi_dma_map_sg(&sg, buf, len, rspi->chan_tx, DMA_TO_DEVICE)) {
353 ret = -EFAULT;
354 goto end_nomap;
355 }
356 desc = dmaengine_prep_slave_sg(rspi->chan_tx, &sg, 1, DMA_TO_DEVICE,
357 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
358 if (!desc) {
359 ret = -EIO;
360 goto end;
361 }
362
363 /*
364 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
365 * called. So, this driver disables the IRQ while DMA transfer.
366 */
367 disable_irq(rspi->irq);
368
369 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_TXMD, RSPI_SPCR);
370 rspi_enable_irq(rspi, SPCR_SPTIE);
371 rspi->dma_callbacked = 0;
372
373 desc->callback = rspi_dma_complete;
374 desc->callback_param = rspi;
375 dmaengine_submit(desc);
376 dma_async_issue_pending(rspi->chan_tx);
377
378 ret = wait_event_interruptible_timeout(rspi->wait,
379 rspi->dma_callbacked, HZ);
380 if (ret > 0 && rspi->dma_callbacked)
381 ret = 0;
382 else if (!ret)
383 ret = -ETIMEDOUT;
384 rspi_disable_irq(rspi, SPCR_SPTIE);
385
386 enable_irq(rspi->irq);
387
388end:
389 rspi_dma_unmap_sg(&sg, rspi->chan_tx, DMA_TO_DEVICE);
390end_nomap:
391 if (rspi->dma_width_16bit)
392 kfree(buf);
393
394 return ret;
395}
396
397static void rspi_receive_init(struct rspi_data *rspi)
398{
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900399 unsigned char spsr;
400
401 spsr = rspi_read8(rspi, RSPI_SPSR);
402 if (spsr & SPSR_SPRF)
403 rspi_read16(rspi, RSPI_SPDR); /* dummy read */
404 if (spsr & SPSR_OVRF)
405 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF,
406 RSPI_SPCR);
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900407}
408
409static int rspi_receive_pio(struct rspi_data *rspi, struct spi_message *mesg,
410 struct spi_transfer *t)
411{
412 int remain = t->len;
413 u8 *data;
414
415 rspi_receive_init(rspi);
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900416
417 data = (u8 *)t->rx_buf;
418 while (remain > 0) {
419 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD,
420 RSPI_SPCR);
421
422 if (rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE) < 0) {
423 dev_err(&rspi->master->dev,
424 "%s: tx empty timeout\n", __func__);
425 return -ETIMEDOUT;
426 }
427 /* dummy write for generate clock */
428 rspi_write16(rspi, 0x00, RSPI_SPDR);
429
430 if (rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE) < 0) {
431 dev_err(&rspi->master->dev,
432 "%s: receive timeout\n", __func__);
433 return -ETIMEDOUT;
434 }
435 /* SPDR allows 16 or 32-bit access only */
436 *data = (u8)rspi_read16(rspi, RSPI_SPDR);
437
438 data++;
439 remain--;
440 }
441
442 return 0;
443}
444
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900445static int rspi_receive_dma(struct rspi_data *rspi, struct spi_transfer *t)
446{
447 struct scatterlist sg, sg_dummy;
448 void *dummy = NULL, *rx_buf = NULL;
449 struct dma_async_tx_descriptor *desc, *desc_dummy;
450 unsigned len;
451 int ret = 0;
452
453 if (rspi->dma_width_16bit) {
454 /*
455 * If DMAC bus width is 16-bit, the driver allocates a dummy
456 * buffer. And, finally the driver converts the DMAC data into
457 * actual data as the following format:
458 * DMAC data: 1st byte, dummy, 2nd byte, dummy ...
459 * actual data: 1st byte, 2nd byte ...
460 */
461 len = t->len * 2;
462 rx_buf = kmalloc(len, GFP_KERNEL);
463 if (!rx_buf)
464 return -ENOMEM;
465 } else {
466 len = t->len;
467 rx_buf = t->rx_buf;
468 }
469
470 /* prepare dummy transfer to generate SPI clocks */
471 dummy = kzalloc(len, GFP_KERNEL);
472 if (!dummy) {
473 ret = -ENOMEM;
474 goto end_nomap;
475 }
476 if (!rspi_dma_map_sg(&sg_dummy, dummy, len, rspi->chan_tx,
477 DMA_TO_DEVICE)) {
478 ret = -EFAULT;
479 goto end_nomap;
480 }
481 desc_dummy = dmaengine_prep_slave_sg(rspi->chan_tx, &sg_dummy, 1,
482 DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
483 if (!desc_dummy) {
484 ret = -EIO;
485 goto end_dummy_mapped;
486 }
487
488 /* prepare receive transfer */
489 if (!rspi_dma_map_sg(&sg, rx_buf, len, rspi->chan_rx,
490 DMA_FROM_DEVICE)) {
491 ret = -EFAULT;
492 goto end_dummy_mapped;
493
494 }
495 desc = dmaengine_prep_slave_sg(rspi->chan_rx, &sg, 1, DMA_FROM_DEVICE,
496 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
497 if (!desc) {
498 ret = -EIO;
499 goto end;
500 }
501
502 rspi_receive_init(rspi);
503
504 /*
505 * DMAC needs SPTIE, but if SPTIE is set, this IRQ routine will be
506 * called. So, this driver disables the IRQ while DMA transfer.
507 */
508 disable_irq(rspi->irq);
509
510 rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_TXMD, RSPI_SPCR);
511 rspi_enable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
512 rspi->dma_callbacked = 0;
513
514 desc->callback = rspi_dma_complete;
515 desc->callback_param = rspi;
516 dmaengine_submit(desc);
517 dma_async_issue_pending(rspi->chan_rx);
518
519 desc_dummy->callback = NULL; /* No callback */
520 dmaengine_submit(desc_dummy);
521 dma_async_issue_pending(rspi->chan_tx);
522
523 ret = wait_event_interruptible_timeout(rspi->wait,
524 rspi->dma_callbacked, HZ);
525 if (ret > 0 && rspi->dma_callbacked)
526 ret = 0;
527 else if (!ret)
528 ret = -ETIMEDOUT;
529 rspi_disable_irq(rspi, SPCR_SPTIE | SPCR_SPRIE);
530
531 enable_irq(rspi->irq);
532
533end:
534 rspi_dma_unmap_sg(&sg, rspi->chan_rx, DMA_FROM_DEVICE);
535end_dummy_mapped:
536 rspi_dma_unmap_sg(&sg_dummy, rspi->chan_tx, DMA_TO_DEVICE);
537end_nomap:
538 if (rspi->dma_width_16bit) {
539 if (!ret)
540 rspi_memory_from_8bit(t->rx_buf, rx_buf, t->len);
541 kfree(rx_buf);
542 }
543 kfree(dummy);
544
545 return ret;
546}
547
548static int rspi_is_dma(struct rspi_data *rspi, struct spi_transfer *t)
549{
550 if (t->tx_buf && rspi->chan_tx)
551 return 1;
552 /* If the module receives data by DMAC, it also needs TX DMAC */
553 if (t->rx_buf && rspi->chan_tx && rspi->chan_rx)
554 return 1;
555
556 return 0;
557}
558
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900559static void rspi_work(struct work_struct *work)
560{
561 struct rspi_data *rspi = container_of(work, struct rspi_data, ws);
562 struct spi_message *mesg;
563 struct spi_transfer *t;
564 unsigned long flags;
565 int ret;
566
567 spin_lock_irqsave(&rspi->lock, flags);
568 while (!list_empty(&rspi->queue)) {
569 mesg = list_entry(rspi->queue.next, struct spi_message, queue);
570 list_del_init(&mesg->queue);
571 spin_unlock_irqrestore(&rspi->lock, flags);
572
573 rspi_assert_ssl(rspi);
574
575 list_for_each_entry(t, &mesg->transfers, transfer_list) {
576 if (t->tx_buf) {
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900577 if (rspi_is_dma(rspi, t))
578 ret = rspi_send_dma(rspi, t);
579 else
580 ret = rspi_send_pio(rspi, mesg, t);
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900581 if (ret < 0)
582 goto error;
583 }
584 if (t->rx_buf) {
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900585 if (rspi_is_dma(rspi, t))
586 ret = rspi_receive_dma(rspi, t);
587 else
588 ret = rspi_receive_pio(rspi, mesg, t);
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900589 if (ret < 0)
590 goto error;
591 }
592 mesg->actual_length += t->len;
593 }
594 rspi_negate_ssl(rspi);
595
596 mesg->status = 0;
597 mesg->complete(mesg->context);
598
599 spin_lock_irqsave(&rspi->lock, flags);
600 }
601
602 return;
603
604error:
605 mesg->status = ret;
606 mesg->complete(mesg->context);
607}
608
609static int rspi_setup(struct spi_device *spi)
610{
611 struct rspi_data *rspi = spi_master_get_devdata(spi->master);
612
613 if (!spi->bits_per_word)
614 spi->bits_per_word = 8;
615 rspi->max_speed_hz = spi->max_speed_hz;
616
617 rspi_set_config_register(rspi, 8);
618
619 return 0;
620}
621
622static int rspi_transfer(struct spi_device *spi, struct spi_message *mesg)
623{
624 struct rspi_data *rspi = spi_master_get_devdata(spi->master);
625 unsigned long flags;
626
627 mesg->actual_length = 0;
628 mesg->status = -EINPROGRESS;
629
630 spin_lock_irqsave(&rspi->lock, flags);
631 list_add_tail(&mesg->queue, &rspi->queue);
632 schedule_work(&rspi->ws);
633 spin_unlock_irqrestore(&rspi->lock, flags);
634
635 return 0;
636}
637
638static void rspi_cleanup(struct spi_device *spi)
639{
640}
641
642static irqreturn_t rspi_irq(int irq, void *_sr)
643{
644 struct rspi_data *rspi = (struct rspi_data *)_sr;
645 unsigned long spsr;
646 irqreturn_t ret = IRQ_NONE;
647 unsigned char disable_irq = 0;
648
649 rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR);
650 if (spsr & SPSR_SPRF)
651 disable_irq |= SPCR_SPRIE;
652 if (spsr & SPSR_SPTEF)
653 disable_irq |= SPCR_SPTIE;
654
655 if (disable_irq) {
656 ret = IRQ_HANDLED;
657 rspi_disable_irq(rspi, disable_irq);
658 wake_up(&rspi->wait);
659 }
660
661 return ret;
662}
663
Grant Likelyfd4a3192012-12-07 16:57:14 +0000664static int rspi_request_dma(struct rspi_data *rspi,
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900665 struct platform_device *pdev)
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900666{
667 struct rspi_plat_data *rspi_pd = pdev->dev.platform_data;
668 dma_cap_mask_t mask;
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900669 struct dma_slave_config cfg;
670 int ret;
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900671
672 if (!rspi_pd)
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900673 return 0; /* The driver assumes no error. */
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900674
675 rspi->dma_width_16bit = rspi_pd->dma_width_16bit;
676
677 /* If the module receives data by DMAC, it also needs TX DMAC */
678 if (rspi_pd->dma_rx_id && rspi_pd->dma_tx_id) {
679 dma_cap_zero(mask);
680 dma_cap_set(DMA_SLAVE, mask);
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900681 rspi->chan_rx = dma_request_channel(mask, shdma_chan_filter,
682 (void *)rspi_pd->dma_rx_id);
683 if (rspi->chan_rx) {
684 cfg.slave_id = rspi_pd->dma_rx_id;
685 cfg.direction = DMA_DEV_TO_MEM;
686 ret = dmaengine_slave_config(rspi->chan_rx, &cfg);
687 if (!ret)
688 dev_info(&pdev->dev, "Use DMA when rx.\n");
689 else
690 return ret;
691 }
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900692 }
693 if (rspi_pd->dma_tx_id) {
694 dma_cap_zero(mask);
695 dma_cap_set(DMA_SLAVE, mask);
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900696 rspi->chan_tx = dma_request_channel(mask, shdma_chan_filter,
697 (void *)rspi_pd->dma_tx_id);
698 if (rspi->chan_tx) {
699 cfg.slave_id = rspi_pd->dma_tx_id;
700 cfg.direction = DMA_MEM_TO_DEV;
701 ret = dmaengine_slave_config(rspi->chan_tx, &cfg);
702 if (!ret)
703 dev_info(&pdev->dev, "Use DMA when tx\n");
704 else
705 return ret;
706 }
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900707 }
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900708
709 return 0;
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900710}
711
Grant Likelyfd4a3192012-12-07 16:57:14 +0000712static void rspi_release_dma(struct rspi_data *rspi)
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900713{
714 if (rspi->chan_tx)
715 dma_release_channel(rspi->chan_tx);
716 if (rspi->chan_rx)
717 dma_release_channel(rspi->chan_rx);
718}
719
Grant Likelyfd4a3192012-12-07 16:57:14 +0000720static int rspi_remove(struct platform_device *pdev)
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900721{
722 struct rspi_data *rspi = dev_get_drvdata(&pdev->dev);
723
724 spi_unregister_master(rspi->master);
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900725 rspi_release_dma(rspi);
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900726 free_irq(platform_get_irq(pdev, 0), rspi);
727 clk_put(rspi->clk);
728 iounmap(rspi->addr);
729 spi_master_put(rspi->master);
730
731 return 0;
732}
733
Grant Likelyfd4a3192012-12-07 16:57:14 +0000734static int rspi_probe(struct platform_device *pdev)
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900735{
736 struct resource *res;
737 struct spi_master *master;
738 struct rspi_data *rspi;
739 int ret, irq;
740 char clk_name[16];
741
742 /* get base addr */
743 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
744 if (unlikely(res == NULL)) {
745 dev_err(&pdev->dev, "invalid resource\n");
746 return -EINVAL;
747 }
748
749 irq = platform_get_irq(pdev, 0);
750 if (irq < 0) {
751 dev_err(&pdev->dev, "platform_get_irq error\n");
752 return -ENODEV;
753 }
754
755 master = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data));
756 if (master == NULL) {
757 dev_err(&pdev->dev, "spi_alloc_master error.\n");
758 return -ENOMEM;
759 }
760
761 rspi = spi_master_get_devdata(master);
762 dev_set_drvdata(&pdev->dev, rspi);
763
764 rspi->master = master;
765 rspi->addr = ioremap(res->start, resource_size(res));
766 if (rspi->addr == NULL) {
767 dev_err(&pdev->dev, "ioremap error.\n");
768 ret = -ENOMEM;
769 goto error1;
770 }
771
772 snprintf(clk_name, sizeof(clk_name), "rspi%d", pdev->id);
773 rspi->clk = clk_get(&pdev->dev, clk_name);
774 if (IS_ERR(rspi->clk)) {
775 dev_err(&pdev->dev, "cannot get clock\n");
776 ret = PTR_ERR(rspi->clk);
777 goto error2;
778 }
779 clk_enable(rspi->clk);
780
781 INIT_LIST_HEAD(&rspi->queue);
782 spin_lock_init(&rspi->lock);
783 INIT_WORK(&rspi->ws, rspi_work);
784 init_waitqueue_head(&rspi->wait);
785
786 master->num_chipselect = 2;
787 master->bus_num = pdev->id;
788 master->setup = rspi_setup;
789 master->transfer = rspi_transfer;
790 master->cleanup = rspi_cleanup;
791
792 ret = request_irq(irq, rspi_irq, 0, dev_name(&pdev->dev), rspi);
793 if (ret < 0) {
794 dev_err(&pdev->dev, "request_irq error\n");
795 goto error3;
796 }
797
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900798 rspi->irq = irq;
Shimoda, Yoshihiro0243c532012-08-02 17:17:33 +0900799 ret = rspi_request_dma(rspi, pdev);
800 if (ret < 0) {
801 dev_err(&pdev->dev, "rspi_request_dma failed.\n");
802 goto error4;
803 }
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900804
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900805 ret = spi_register_master(master);
806 if (ret < 0) {
807 dev_err(&pdev->dev, "spi_register_master error.\n");
808 goto error4;
809 }
810
811 dev_info(&pdev->dev, "probed\n");
812
813 return 0;
814
815error4:
Shimoda, Yoshihiroa3633fe2012-04-20 14:50:36 +0900816 rspi_release_dma(rspi);
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900817 free_irq(irq, rspi);
818error3:
819 clk_put(rspi->clk);
820error2:
821 iounmap(rspi->addr);
822error1:
823 spi_master_put(master);
824
825 return ret;
826}
827
828static struct platform_driver rspi_driver = {
829 .probe = rspi_probe,
Grant Likelyfd4a3192012-12-07 16:57:14 +0000830 .remove = rspi_remove,
Shimoda, Yoshihiro0b2182d2012-03-07 14:46:25 +0900831 .driver = {
832 .name = "rspi",
833 .owner = THIS_MODULE,
834 },
835};
836module_platform_driver(rspi_driver);
837
838MODULE_DESCRIPTION("Renesas RSPI bus driver");
839MODULE_LICENSE("GPL v2");
840MODULE_AUTHOR("Yoshihiro Shimoda");
841MODULE_ALIAS("platform:rspi");