Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * OMAP2 McSPI controller driver
4 *
5 * Copyright (C) 2005, 2006 Nokia Corporation
6 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
7 * Juha Yrj�l� <juha.yrjola@nokia.com>
8 */
9
10#include <linux/kernel.h>
11#include <linux/interrupt.h>
12#include <linux/module.h>
13#include <linux/device.h>
14#include <linux/delay.h>
15#include <linux/dma-mapping.h>
16#include <linux/dmaengine.h>
17#include <linux/pinctrl/consumer.h>
18#include <linux/platform_device.h>
19#include <linux/err.h>
20#include <linux/clk.h>
21#include <linux/io.h>
22#include <linux/slab.h>
23#include <linux/pm_runtime.h>
24#include <linux/of.h>
25#include <linux/of_device.h>
26#include <linux/gcd.h>
27#include <linux/iopoll.h>
28
29#include <linux/spi/spi.h>
30#include <linux/gpio.h>
31
32#include <linux/platform_data/spi-omap2-mcspi.h>
33
34#define OMAP2_MCSPI_MAX_FREQ 48000000
35#define OMAP2_MCSPI_MAX_DIVIDER 4096
36#define OMAP2_MCSPI_MAX_FIFODEPTH 64
37#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
38#define SPI_AUTOSUSPEND_TIMEOUT 2000
39
40#define OMAP2_MCSPI_REVISION 0x00
41#define OMAP2_MCSPI_SYSSTATUS 0x14
42#define OMAP2_MCSPI_IRQSTATUS 0x18
43#define OMAP2_MCSPI_IRQENABLE 0x1c
44#define OMAP2_MCSPI_WAKEUPENABLE 0x20
45#define OMAP2_MCSPI_SYST 0x24
46#define OMAP2_MCSPI_MODULCTRL 0x28
47#define OMAP2_MCSPI_XFERLEVEL 0x7c
48
49/* per-channel banks, 0x14 bytes each, first is: */
50#define OMAP2_MCSPI_CHCONF0 0x2c
51#define OMAP2_MCSPI_CHSTAT0 0x30
52#define OMAP2_MCSPI_CHCTRL0 0x34
53#define OMAP2_MCSPI_TX0 0x38
54#define OMAP2_MCSPI_RX0 0x3c
55
56/* per-register bitmasks: */
57#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
58
59#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
60#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
61#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
62
63#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
64#define OMAP2_MCSPI_CHCONF_POL BIT(1)
65#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
66#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
67#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
68#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
69#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
70#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
71#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
72#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
73#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
74#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
75#define OMAP2_MCSPI_CHCONF_IS BIT(18)
76#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
77#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
78#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
79#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
80#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
81
82#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
83#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
84#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
85#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
86
87#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
88#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
89
90#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
91
92/* We have 2 DMA channels per CS, one for RX and one for TX */
93struct omap2_mcspi_dma {
94 struct dma_chan *dma_tx;
95 struct dma_chan *dma_rx;
96
97 struct completion dma_tx_completion;
98 struct completion dma_rx_completion;
99
100 char dma_rx_ch_name[14];
101 char dma_tx_ch_name[14];
102};
103
104/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
105 * cache operations; better heuristics consider wordsize and bitrate.
106 */
107#define DMA_MIN_BYTES 160
108
109
110/*
111 * Used for context save and restore, structure members to be updated whenever
112 * corresponding registers are modified.
113 */
114struct omap2_mcspi_regs {
115 u32 modulctrl;
116 u32 wakeupenable;
117 struct list_head cs;
118};
119
120struct omap2_mcspi {
121 struct completion txdone;
122 struct spi_master *master;
123 /* Virtual base address of the controller */
124 void __iomem *base;
125 unsigned long phys;
126 /* SPI1 has 4 channels, while SPI2 has 2 */
127 struct omap2_mcspi_dma *dma_channels;
128 struct device *dev;
129 struct omap2_mcspi_regs ctx;
130 int fifo_depth;
131 bool slave_aborted;
132 unsigned int pin_dir:1;
133};
134
135struct omap2_mcspi_cs {
136 void __iomem *base;
137 unsigned long phys;
138 int word_len;
139 u16 mode;
140 struct list_head node;
141 /* Context save and restore shadow register */
142 u32 chconf0, chctrl0;
143};
144
145static inline void mcspi_write_reg(struct spi_master *master,
146 int idx, u32 val)
147{
148 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
149
150 writel_relaxed(val, mcspi->base + idx);
151}
152
153static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
154{
155 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
156
157 return readl_relaxed(mcspi->base + idx);
158}
159
160static inline void mcspi_write_cs_reg(const struct spi_device *spi,
161 int idx, u32 val)
162{
163 struct omap2_mcspi_cs *cs = spi->controller_state;
164
165 writel_relaxed(val, cs->base + idx);
166}
167
168static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
169{
170 struct omap2_mcspi_cs *cs = spi->controller_state;
171
172 return readl_relaxed(cs->base + idx);
173}
174
175static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
176{
177 struct omap2_mcspi_cs *cs = spi->controller_state;
178
179 return cs->chconf0;
180}
181
182static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
183{
184 struct omap2_mcspi_cs *cs = spi->controller_state;
185
186 cs->chconf0 = val;
187 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
188 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
189}
190
191static inline int mcspi_bytes_per_word(int word_len)
192{
193 if (word_len <= 8)
194 return 1;
195 else if (word_len <= 16)
196 return 2;
197 else /* word_len <= 32 */
198 return 4;
199}
200
201static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
202 int is_read, int enable)
203{
204 u32 l, rw;
205
206 l = mcspi_cached_chconf0(spi);
207
208 if (is_read) /* 1 is read, 0 write */
209 rw = OMAP2_MCSPI_CHCONF_DMAR;
210 else
211 rw = OMAP2_MCSPI_CHCONF_DMAW;
212
213 if (enable)
214 l |= rw;
215 else
216 l &= ~rw;
217
218 mcspi_write_chconf0(spi, l);
219}
220
221static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
222{
223 struct omap2_mcspi_cs *cs = spi->controller_state;
224 u32 l;
225
226 l = cs->chctrl0;
227 if (enable)
228 l |= OMAP2_MCSPI_CHCTRL_EN;
229 else
230 l &= ~OMAP2_MCSPI_CHCTRL_EN;
231 cs->chctrl0 = l;
232 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
233 /* Flash post-writes */
234 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
235}
236
237static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
238{
239 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
240 u32 l;
241
242 /* The controller handles the inverted chip selects
243 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
244 * the inversion from the core spi_set_cs function.
245 */
246 if (spi->mode & SPI_CS_HIGH)
247 enable = !enable;
248
249 if (spi->controller_state) {
250 int err = pm_runtime_get_sync(mcspi->dev);
251 if (err < 0) {
252 pm_runtime_put_noidle(mcspi->dev);
253 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
254 return;
255 }
256
257 l = mcspi_cached_chconf0(spi);
258
259 if (enable)
260 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
261 else
262 l |= OMAP2_MCSPI_CHCONF_FORCE;
263
264 mcspi_write_chconf0(spi, l);
265
266 pm_runtime_mark_last_busy(mcspi->dev);
267 pm_runtime_put_autosuspend(mcspi->dev);
268 }
269}
270
271static void omap2_mcspi_set_mode(struct spi_master *master)
272{
273 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
274 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
275 u32 l;
276
277 /*
278 * Choose master or slave mode
279 */
280 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
281 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
282 if (spi_controller_is_slave(master)) {
283 l |= (OMAP2_MCSPI_MODULCTRL_MS);
284 } else {
285 l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
286 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
287 }
288 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
289
290 ctx->modulctrl = l;
291}
292
293static void omap2_mcspi_set_fifo(const struct spi_device *spi,
294 struct spi_transfer *t, int enable)
295{
296 struct spi_master *master = spi->master;
297 struct omap2_mcspi_cs *cs = spi->controller_state;
298 struct omap2_mcspi *mcspi;
299 unsigned int wcnt;
300 int max_fifo_depth, bytes_per_word;
301 u32 chconf, xferlevel;
302
303 mcspi = spi_master_get_devdata(master);
304
305 chconf = mcspi_cached_chconf0(spi);
306 if (enable) {
307 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
308 if (t->len % bytes_per_word != 0)
309 goto disable_fifo;
310
311 if (t->rx_buf != NULL && t->tx_buf != NULL)
312 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
313 else
314 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
315
316 wcnt = t->len / bytes_per_word;
317 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
318 goto disable_fifo;
319
320 xferlevel = wcnt << 16;
321 if (t->rx_buf != NULL) {
322 chconf |= OMAP2_MCSPI_CHCONF_FFER;
323 xferlevel |= (bytes_per_word - 1) << 8;
324 }
325
326 if (t->tx_buf != NULL) {
327 chconf |= OMAP2_MCSPI_CHCONF_FFET;
328 xferlevel |= bytes_per_word - 1;
329 }
330
331 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
332 mcspi_write_chconf0(spi, chconf);
333 mcspi->fifo_depth = max_fifo_depth;
334
335 return;
336 }
337
338disable_fifo:
339 if (t->rx_buf != NULL)
340 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
341
342 if (t->tx_buf != NULL)
343 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
344
345 mcspi_write_chconf0(spi, chconf);
346 mcspi->fifo_depth = 0;
347}
348
349static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
350{
351 u32 val;
352
353 return readl_poll_timeout(reg, val, val & bit, 1, MSEC_PER_SEC);
354}
355
356static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi,
357 struct completion *x)
358{
359 if (spi_controller_is_slave(mcspi->master)) {
360 if (wait_for_completion_interruptible(x) ||
361 mcspi->slave_aborted)
362 return -EINTR;
363 } else {
364 wait_for_completion(x);
365 }
366
367 return 0;
368}
369
370static void omap2_mcspi_rx_callback(void *data)
371{
372 struct spi_device *spi = data;
373 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
374 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
375
376 /* We must disable the DMA RX request */
377 omap2_mcspi_set_dma_req(spi, 1, 0);
378
379 complete(&mcspi_dma->dma_rx_completion);
380}
381
382static void omap2_mcspi_tx_callback(void *data)
383{
384 struct spi_device *spi = data;
385 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
386 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
387
388 /* We must disable the DMA TX request */
389 omap2_mcspi_set_dma_req(spi, 0, 0);
390
391 complete(&mcspi_dma->dma_tx_completion);
392}
393
394static void omap2_mcspi_tx_dma(struct spi_device *spi,
395 struct spi_transfer *xfer,
396 struct dma_slave_config cfg)
397{
398 struct omap2_mcspi *mcspi;
399 struct omap2_mcspi_dma *mcspi_dma;
400
401 mcspi = spi_master_get_devdata(spi->master);
402 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
403
404 if (mcspi_dma->dma_tx) {
405 struct dma_async_tx_descriptor *tx;
406
407 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
408
409 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
410 xfer->tx_sg.nents,
411 DMA_MEM_TO_DEV,
412 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
413 if (tx) {
414 tx->callback = omap2_mcspi_tx_callback;
415 tx->callback_param = spi;
416 dmaengine_submit(tx);
417 } else {
418 /* FIXME: fall back to PIO? */
419 }
420 }
421 dma_async_issue_pending(mcspi_dma->dma_tx);
422 omap2_mcspi_set_dma_req(spi, 0, 1);
423
424}
425
426static unsigned
427omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
428 struct dma_slave_config cfg,
429 unsigned es)
430{
431 struct omap2_mcspi *mcspi;
432 struct omap2_mcspi_dma *mcspi_dma;
433 unsigned int count, transfer_reduction = 0;
434 struct scatterlist *sg_out[2];
435 int nb_sizes = 0, out_mapped_nents[2], ret, x;
436 size_t sizes[2];
437 u32 l;
438 int elements = 0;
439 int word_len, element_count;
440 struct omap2_mcspi_cs *cs = spi->controller_state;
441 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
442
443 mcspi = spi_master_get_devdata(spi->master);
444 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
445 count = xfer->len;
446
447 /*
448 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
449 * it mentions reducing DMA transfer length by one element in master
450 * normal mode.
451 */
452 if (mcspi->fifo_depth == 0)
453 transfer_reduction = es;
454
455 word_len = cs->word_len;
456 l = mcspi_cached_chconf0(spi);
457
458 if (word_len <= 8)
459 element_count = count;
460 else if (word_len <= 16)
461 element_count = count >> 1;
462 else /* word_len <= 32 */
463 element_count = count >> 2;
464
465 if (mcspi_dma->dma_rx) {
466 struct dma_async_tx_descriptor *tx;
467
468 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
469
470 /*
471 * Reduce DMA transfer length by one more if McSPI is
472 * configured in turbo mode.
473 */
474 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
475 transfer_reduction += es;
476
477 if (transfer_reduction) {
478 /* Split sgl into two. The second sgl won't be used. */
479 sizes[0] = count - transfer_reduction;
480 sizes[1] = transfer_reduction;
481 nb_sizes = 2;
482 } else {
483 /*
484 * Don't bother splitting the sgl. This essentially
485 * clones the original sgl.
486 */
487 sizes[0] = count;
488 nb_sizes = 1;
489 }
490
491 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
492 0, nb_sizes,
493 sizes,
494 sg_out, out_mapped_nents,
495 GFP_KERNEL);
496
497 if (ret < 0) {
498 dev_err(&spi->dev, "sg_split failed\n");
499 return 0;
500 }
501
502 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
503 sg_out[0],
504 out_mapped_nents[0],
505 DMA_DEV_TO_MEM,
506 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
507 if (tx) {
508 tx->callback = omap2_mcspi_rx_callback;
509 tx->callback_param = spi;
510 dmaengine_submit(tx);
511 } else {
512 /* FIXME: fall back to PIO? */
513 }
514 }
515
516 dma_async_issue_pending(mcspi_dma->dma_rx);
517 omap2_mcspi_set_dma_req(spi, 1, 1);
518
519 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
520 if (ret || mcspi->slave_aborted) {
521 dmaengine_terminate_sync(mcspi_dma->dma_rx);
522 omap2_mcspi_set_dma_req(spi, 1, 0);
523 return 0;
524 }
525
526 for (x = 0; x < nb_sizes; x++)
527 kfree(sg_out[x]);
528
529 if (mcspi->fifo_depth > 0)
530 return count;
531
532 /*
533 * Due to the DMA transfer length reduction the missing bytes must
534 * be read manually to receive all of the expected data.
535 */
536 omap2_mcspi_set_enable(spi, 0);
537
538 elements = element_count - 1;
539
540 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
541 elements--;
542
543 if (!mcspi_wait_for_reg_bit(chstat_reg,
544 OMAP2_MCSPI_CHSTAT_RXS)) {
545 u32 w;
546
547 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
548 if (word_len <= 8)
549 ((u8 *)xfer->rx_buf)[elements++] = w;
550 else if (word_len <= 16)
551 ((u16 *)xfer->rx_buf)[elements++] = w;
552 else /* word_len <= 32 */
553 ((u32 *)xfer->rx_buf)[elements++] = w;
554 } else {
555 int bytes_per_word = mcspi_bytes_per_word(word_len);
556 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
557 count -= (bytes_per_word << 1);
558 omap2_mcspi_set_enable(spi, 1);
559 return count;
560 }
561 }
562 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
563 u32 w;
564
565 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
566 if (word_len <= 8)
567 ((u8 *)xfer->rx_buf)[elements] = w;
568 else if (word_len <= 16)
569 ((u16 *)xfer->rx_buf)[elements] = w;
570 else /* word_len <= 32 */
571 ((u32 *)xfer->rx_buf)[elements] = w;
572 } else {
573 dev_err(&spi->dev, "DMA RX last word empty\n");
574 count -= mcspi_bytes_per_word(word_len);
575 }
576 omap2_mcspi_set_enable(spi, 1);
577 return count;
578}
579
580static unsigned
581omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
582{
583 struct omap2_mcspi *mcspi;
584 struct omap2_mcspi_cs *cs = spi->controller_state;
585 struct omap2_mcspi_dma *mcspi_dma;
586 unsigned int count;
587 u8 *rx;
588 const u8 *tx;
589 struct dma_slave_config cfg;
590 enum dma_slave_buswidth width;
591 unsigned es;
592 void __iomem *chstat_reg;
593 void __iomem *irqstat_reg;
594 int wait_res;
595
596 mcspi = spi_master_get_devdata(spi->master);
597 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
598
599 if (cs->word_len <= 8) {
600 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
601 es = 1;
602 } else if (cs->word_len <= 16) {
603 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
604 es = 2;
605 } else {
606 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
607 es = 4;
608 }
609
610 count = xfer->len;
611
612 memset(&cfg, 0, sizeof(cfg));
613 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
614 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
615 cfg.src_addr_width = width;
616 cfg.dst_addr_width = width;
617 cfg.src_maxburst = 1;
618 cfg.dst_maxburst = 1;
619
620 rx = xfer->rx_buf;
621 tx = xfer->tx_buf;
622
623 mcspi->slave_aborted = false;
624 reinit_completion(&mcspi_dma->dma_tx_completion);
625 reinit_completion(&mcspi_dma->dma_rx_completion);
626 reinit_completion(&mcspi->txdone);
627 if (tx) {
628 /* Enable EOW IRQ to know end of tx in slave mode */
629 if (spi_controller_is_slave(spi->master))
630 mcspi_write_reg(spi->master,
631 OMAP2_MCSPI_IRQENABLE,
632 OMAP2_MCSPI_IRQSTATUS_EOW);
633 omap2_mcspi_tx_dma(spi, xfer, cfg);
634 }
635
636 if (rx != NULL)
637 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
638
639 if (tx != NULL) {
640 int ret;
641
642 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
643 if (ret || mcspi->slave_aborted) {
644 dmaengine_terminate_sync(mcspi_dma->dma_tx);
645 omap2_mcspi_set_dma_req(spi, 0, 0);
646 return 0;
647 }
648
649 if (spi_controller_is_slave(mcspi->master)) {
650 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
651 if (ret || mcspi->slave_aborted)
652 return 0;
653 }
654
655 if (mcspi->fifo_depth > 0) {
656 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
657
658 if (mcspi_wait_for_reg_bit(irqstat_reg,
659 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
660 dev_err(&spi->dev, "EOW timed out\n");
661
662 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
663 OMAP2_MCSPI_IRQSTATUS_EOW);
664 }
665
666 /* for TX_ONLY mode, be sure all words have shifted out */
667 if (rx == NULL) {
668 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
669 if (mcspi->fifo_depth > 0) {
670 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
671 OMAP2_MCSPI_CHSTAT_TXFFE);
672 if (wait_res < 0)
673 dev_err(&spi->dev, "TXFFE timed out\n");
674 } else {
675 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
676 OMAP2_MCSPI_CHSTAT_TXS);
677 if (wait_res < 0)
678 dev_err(&spi->dev, "TXS timed out\n");
679 }
680 if (wait_res >= 0 &&
681 (mcspi_wait_for_reg_bit(chstat_reg,
682 OMAP2_MCSPI_CHSTAT_EOT) < 0))
683 dev_err(&spi->dev, "EOT timed out\n");
684 }
685 }
686 return count;
687}
688
689static unsigned
690omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
691{
692 struct omap2_mcspi_cs *cs = spi->controller_state;
693 unsigned int count, c;
694 u32 l;
695 void __iomem *base = cs->base;
696 void __iomem *tx_reg;
697 void __iomem *rx_reg;
698 void __iomem *chstat_reg;
699 int word_len;
700
701 count = xfer->len;
702 c = count;
703 word_len = cs->word_len;
704
705 l = mcspi_cached_chconf0(spi);
706
707 /* We store the pre-calculated register addresses on stack to speed
708 * up the transfer loop. */
709 tx_reg = base + OMAP2_MCSPI_TX0;
710 rx_reg = base + OMAP2_MCSPI_RX0;
711 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
712
713 if (c < (word_len>>3))
714 return 0;
715
716 if (word_len <= 8) {
717 u8 *rx;
718 const u8 *tx;
719
720 rx = xfer->rx_buf;
721 tx = xfer->tx_buf;
722
723 do {
724 c -= 1;
725 if (tx != NULL) {
726 if (mcspi_wait_for_reg_bit(chstat_reg,
727 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
728 dev_err(&spi->dev, "TXS timed out\n");
729 goto out;
730 }
731 dev_vdbg(&spi->dev, "write-%d %02x\n",
732 word_len, *tx);
733 writel_relaxed(*tx++, tx_reg);
734 }
735 if (rx != NULL) {
736 if (mcspi_wait_for_reg_bit(chstat_reg,
737 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
738 dev_err(&spi->dev, "RXS timed out\n");
739 goto out;
740 }
741
742 if (c == 1 && tx == NULL &&
743 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
744 omap2_mcspi_set_enable(spi, 0);
745 *rx++ = readl_relaxed(rx_reg);
746 dev_vdbg(&spi->dev, "read-%d %02x\n",
747 word_len, *(rx - 1));
748 if (mcspi_wait_for_reg_bit(chstat_reg,
749 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
750 dev_err(&spi->dev,
751 "RXS timed out\n");
752 goto out;
753 }
754 c = 0;
755 } else if (c == 0 && tx == NULL) {
756 omap2_mcspi_set_enable(spi, 0);
757 }
758
759 *rx++ = readl_relaxed(rx_reg);
760 dev_vdbg(&spi->dev, "read-%d %02x\n",
761 word_len, *(rx - 1));
762 }
763 } while (c);
764 } else if (word_len <= 16) {
765 u16 *rx;
766 const u16 *tx;
767
768 rx = xfer->rx_buf;
769 tx = xfer->tx_buf;
770 do {
771 c -= 2;
772 if (tx != NULL) {
773 if (mcspi_wait_for_reg_bit(chstat_reg,
774 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
775 dev_err(&spi->dev, "TXS timed out\n");
776 goto out;
777 }
778 dev_vdbg(&spi->dev, "write-%d %04x\n",
779 word_len, *tx);
780 writel_relaxed(*tx++, tx_reg);
781 }
782 if (rx != NULL) {
783 if (mcspi_wait_for_reg_bit(chstat_reg,
784 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
785 dev_err(&spi->dev, "RXS timed out\n");
786 goto out;
787 }
788
789 if (c == 2 && tx == NULL &&
790 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
791 omap2_mcspi_set_enable(spi, 0);
792 *rx++ = readl_relaxed(rx_reg);
793 dev_vdbg(&spi->dev, "read-%d %04x\n",
794 word_len, *(rx - 1));
795 if (mcspi_wait_for_reg_bit(chstat_reg,
796 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
797 dev_err(&spi->dev,
798 "RXS timed out\n");
799 goto out;
800 }
801 c = 0;
802 } else if (c == 0 && tx == NULL) {
803 omap2_mcspi_set_enable(spi, 0);
804 }
805
806 *rx++ = readl_relaxed(rx_reg);
807 dev_vdbg(&spi->dev, "read-%d %04x\n",
808 word_len, *(rx - 1));
809 }
810 } while (c >= 2);
811 } else if (word_len <= 32) {
812 u32 *rx;
813 const u32 *tx;
814
815 rx = xfer->rx_buf;
816 tx = xfer->tx_buf;
817 do {
818 c -= 4;
819 if (tx != NULL) {
820 if (mcspi_wait_for_reg_bit(chstat_reg,
821 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
822 dev_err(&spi->dev, "TXS timed out\n");
823 goto out;
824 }
825 dev_vdbg(&spi->dev, "write-%d %08x\n",
826 word_len, *tx);
827 writel_relaxed(*tx++, tx_reg);
828 }
829 if (rx != NULL) {
830 if (mcspi_wait_for_reg_bit(chstat_reg,
831 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
832 dev_err(&spi->dev, "RXS timed out\n");
833 goto out;
834 }
835
836 if (c == 4 && tx == NULL &&
837 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
838 omap2_mcspi_set_enable(spi, 0);
839 *rx++ = readl_relaxed(rx_reg);
840 dev_vdbg(&spi->dev, "read-%d %08x\n",
841 word_len, *(rx - 1));
842 if (mcspi_wait_for_reg_bit(chstat_reg,
843 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
844 dev_err(&spi->dev,
845 "RXS timed out\n");
846 goto out;
847 }
848 c = 0;
849 } else if (c == 0 && tx == NULL) {
850 omap2_mcspi_set_enable(spi, 0);
851 }
852
853 *rx++ = readl_relaxed(rx_reg);
854 dev_vdbg(&spi->dev, "read-%d %08x\n",
855 word_len, *(rx - 1));
856 }
857 } while (c >= 4);
858 }
859
860 /* for TX_ONLY mode, be sure all words have shifted out */
861 if (xfer->rx_buf == NULL) {
862 if (mcspi_wait_for_reg_bit(chstat_reg,
863 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
864 dev_err(&spi->dev, "TXS timed out\n");
865 } else if (mcspi_wait_for_reg_bit(chstat_reg,
866 OMAP2_MCSPI_CHSTAT_EOT) < 0)
867 dev_err(&spi->dev, "EOT timed out\n");
868
869 /* disable chan to purge rx datas received in TX_ONLY transfer,
870 * otherwise these rx datas will affect the direct following
871 * RX_ONLY transfer.
872 */
873 omap2_mcspi_set_enable(spi, 0);
874 }
875out:
876 omap2_mcspi_set_enable(spi, 1);
877 return count - c;
878}
879
880static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
881{
882 u32 div;
883
884 for (div = 0; div < 15; div++)
885 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
886 return div;
887
888 return 15;
889}
890
891/* called only when no transfer is active to this device */
892static int omap2_mcspi_setup_transfer(struct spi_device *spi,
893 struct spi_transfer *t)
894{
895 struct omap2_mcspi_cs *cs = spi->controller_state;
896 struct omap2_mcspi *mcspi;
897 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
898 u8 word_len = spi->bits_per_word;
899 u32 speed_hz = spi->max_speed_hz;
900
901 mcspi = spi_master_get_devdata(spi->master);
902
903 if (t != NULL && t->bits_per_word)
904 word_len = t->bits_per_word;
905
906 cs->word_len = word_len;
907
908 if (t && t->speed_hz)
909 speed_hz = t->speed_hz;
910
911 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
912 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
913 clkd = omap2_mcspi_calc_divisor(speed_hz);
914 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
915 clkg = 0;
916 } else {
917 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
918 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
919 clkd = (div - 1) & 0xf;
920 extclk = (div - 1) >> 4;
921 clkg = OMAP2_MCSPI_CHCONF_CLKG;
922 }
923
924 l = mcspi_cached_chconf0(spi);
925
926 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
927 * REVISIT: this controller could support SPI_3WIRE mode.
928 */
929 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
930 l &= ~OMAP2_MCSPI_CHCONF_IS;
931 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
932 l |= OMAP2_MCSPI_CHCONF_DPE0;
933 } else {
934 l |= OMAP2_MCSPI_CHCONF_IS;
935 l |= OMAP2_MCSPI_CHCONF_DPE1;
936 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
937 }
938
939 /* wordlength */
940 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
941 l |= (word_len - 1) << 7;
942
943 /* set chipselect polarity; manage with FORCE */
944 if (!(spi->mode & SPI_CS_HIGH))
945 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
946 else
947 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
948
949 /* set clock divisor */
950 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
951 l |= clkd << 2;
952
953 /* set clock granularity */
954 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
955 l |= clkg;
956 if (clkg) {
957 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
958 cs->chctrl0 |= extclk << 8;
959 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
960 }
961
962 /* set SPI mode 0..3 */
963 if (spi->mode & SPI_CPOL)
964 l |= OMAP2_MCSPI_CHCONF_POL;
965 else
966 l &= ~OMAP2_MCSPI_CHCONF_POL;
967 if (spi->mode & SPI_CPHA)
968 l |= OMAP2_MCSPI_CHCONF_PHA;
969 else
970 l &= ~OMAP2_MCSPI_CHCONF_PHA;
971
972 mcspi_write_chconf0(spi, l);
973
974 cs->mode = spi->mode;
975
976 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
977 speed_hz,
978 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
979 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
980
981 return 0;
982}
983
984/*
985 * Note that we currently allow DMA only if we get a channel
986 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
987 */
988static int omap2_mcspi_request_dma(struct spi_device *spi)
989{
990 struct spi_master *master = spi->master;
991 struct omap2_mcspi *mcspi;
992 struct omap2_mcspi_dma *mcspi_dma;
993 int ret = 0;
994
995 mcspi = spi_master_get_devdata(master);
996 mcspi_dma = mcspi->dma_channels + spi->chip_select;
997
998 init_completion(&mcspi_dma->dma_rx_completion);
999 init_completion(&mcspi_dma->dma_tx_completion);
1000
1001 mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1002 mcspi_dma->dma_rx_ch_name);
1003 if (IS_ERR(mcspi_dma->dma_rx)) {
1004 ret = PTR_ERR(mcspi_dma->dma_rx);
1005 mcspi_dma->dma_rx = NULL;
1006 goto no_dma;
1007 }
1008
1009 mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1010 mcspi_dma->dma_tx_ch_name);
1011 if (IS_ERR(mcspi_dma->dma_tx)) {
1012 ret = PTR_ERR(mcspi_dma->dma_tx);
1013 mcspi_dma->dma_tx = NULL;
1014 dma_release_channel(mcspi_dma->dma_rx);
1015 mcspi_dma->dma_rx = NULL;
1016 }
1017
1018no_dma:
1019 return ret;
1020}
1021
1022static int omap2_mcspi_setup(struct spi_device *spi)
1023{
1024 int ret;
1025 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1026 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1027 struct omap2_mcspi_dma *mcspi_dma;
1028 struct omap2_mcspi_cs *cs = spi->controller_state;
1029
1030 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1031
1032 if (!cs) {
1033 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1034 if (!cs)
1035 return -ENOMEM;
1036 cs->base = mcspi->base + spi->chip_select * 0x14;
1037 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1038 cs->mode = 0;
1039 cs->chconf0 = 0;
1040 cs->chctrl0 = 0;
1041 spi->controller_state = cs;
1042 /* Link this to context save list */
1043 list_add_tail(&cs->node, &ctx->cs);
1044
1045 if (gpio_is_valid(spi->cs_gpio)) {
1046 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1047 if (ret) {
1048 dev_err(&spi->dev, "failed to request gpio\n");
1049 return ret;
1050 }
1051 gpio_direction_output(spi->cs_gpio,
1052 !(spi->mode & SPI_CS_HIGH));
1053 }
1054 }
1055
1056 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1057 ret = omap2_mcspi_request_dma(spi);
1058 if (ret)
1059 dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1060 ret);
1061 }
1062
1063 ret = pm_runtime_get_sync(mcspi->dev);
1064 if (ret < 0) {
1065 pm_runtime_put_noidle(mcspi->dev);
1066
1067 return ret;
1068 }
1069
1070 ret = omap2_mcspi_setup_transfer(spi, NULL);
1071 pm_runtime_mark_last_busy(mcspi->dev);
1072 pm_runtime_put_autosuspend(mcspi->dev);
1073
1074 return ret;
1075}
1076
1077static void omap2_mcspi_cleanup(struct spi_device *spi)
1078{
1079 struct omap2_mcspi *mcspi;
1080 struct omap2_mcspi_dma *mcspi_dma;
1081 struct omap2_mcspi_cs *cs;
1082
1083 mcspi = spi_master_get_devdata(spi->master);
1084
1085 if (spi->controller_state) {
1086 /* Unlink controller state from context save list */
1087 cs = spi->controller_state;
1088 list_del(&cs->node);
1089
1090 kfree(cs);
1091 }
1092
1093 if (spi->chip_select < spi->master->num_chipselect) {
1094 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1095
1096 if (mcspi_dma->dma_rx) {
1097 dma_release_channel(mcspi_dma->dma_rx);
1098 mcspi_dma->dma_rx = NULL;
1099 }
1100 if (mcspi_dma->dma_tx) {
1101 dma_release_channel(mcspi_dma->dma_tx);
1102 mcspi_dma->dma_tx = NULL;
1103 }
1104 }
1105
1106 if (gpio_is_valid(spi->cs_gpio))
1107 gpio_free(spi->cs_gpio);
1108}
1109
1110static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1111{
1112 struct omap2_mcspi *mcspi = data;
1113 u32 irqstat;
1114
1115 irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1116 if (!irqstat)
1117 return IRQ_NONE;
1118
1119 /* Disable IRQ and wakeup slave xfer task */
1120 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1121 if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1122 complete(&mcspi->txdone);
1123
1124 return IRQ_HANDLED;
1125}
1126
1127static int omap2_mcspi_slave_abort(struct spi_master *master)
1128{
1129 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1130 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1131
1132 mcspi->slave_aborted = true;
1133 complete(&mcspi_dma->dma_rx_completion);
1134 complete(&mcspi_dma->dma_tx_completion);
1135 complete(&mcspi->txdone);
1136
1137 return 0;
1138}
1139
1140static int omap2_mcspi_transfer_one(struct spi_master *master,
1141 struct spi_device *spi,
1142 struct spi_transfer *t)
1143{
1144
1145 /* We only enable one channel at a time -- the one whose message is
1146 * -- although this controller would gladly
1147 * arbitrate among multiple channels. This corresponds to "single
1148 * channel" master mode. As a side effect, we need to manage the
1149 * chipselect with the FORCE bit ... CS != channel enable.
1150 */
1151
1152 struct omap2_mcspi *mcspi;
1153 struct omap2_mcspi_dma *mcspi_dma;
1154 struct omap2_mcspi_cs *cs;
1155 struct omap2_mcspi_device_config *cd;
1156 int par_override = 0;
1157 int status = 0;
1158 u32 chconf;
1159
1160 mcspi = spi_master_get_devdata(master);
1161 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1162 cs = spi->controller_state;
1163 cd = spi->controller_data;
1164
1165 /*
1166 * The slave driver could have changed spi->mode in which case
1167 * it will be different from cs->mode (the current hardware setup).
1168 * If so, set par_override (even though its not a parity issue) so
1169 * omap2_mcspi_setup_transfer will be called to configure the hardware
1170 * with the correct mode on the first iteration of the loop below.
1171 */
1172 if (spi->mode != cs->mode)
1173 par_override = 1;
1174
1175 omap2_mcspi_set_enable(spi, 0);
1176
1177 if (gpio_is_valid(spi->cs_gpio))
1178 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1179
1180 if (par_override ||
1181 (t->speed_hz != spi->max_speed_hz) ||
1182 (t->bits_per_word != spi->bits_per_word)) {
1183 par_override = 1;
1184 status = omap2_mcspi_setup_transfer(spi, t);
1185 if (status < 0)
1186 goto out;
1187 if (t->speed_hz == spi->max_speed_hz &&
1188 t->bits_per_word == spi->bits_per_word)
1189 par_override = 0;
1190 }
1191 if (cd && cd->cs_per_word) {
1192 chconf = mcspi->ctx.modulctrl;
1193 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1194 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1195 mcspi->ctx.modulctrl =
1196 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1197 }
1198
1199 chconf = mcspi_cached_chconf0(spi);
1200 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1201 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1202
1203 if (t->tx_buf == NULL)
1204 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1205 else if (t->rx_buf == NULL)
1206 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1207
1208 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1209 /* Turbo mode is for more than one word */
1210 if (t->len > ((cs->word_len + 7) >> 3))
1211 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1212 }
1213
1214 mcspi_write_chconf0(spi, chconf);
1215
1216 if (t->len) {
1217 unsigned count;
1218
1219 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1220 master->cur_msg_mapped &&
1221 master->can_dma(master, spi, t))
1222 omap2_mcspi_set_fifo(spi, t, 1);
1223
1224 omap2_mcspi_set_enable(spi, 1);
1225
1226 /* RX_ONLY mode needs dummy data in TX reg */
1227 if (t->tx_buf == NULL)
1228 writel_relaxed(0, cs->base
1229 + OMAP2_MCSPI_TX0);
1230
1231 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1232 master->cur_msg_mapped &&
1233 master->can_dma(master, spi, t))
1234 count = omap2_mcspi_txrx_dma(spi, t);
1235 else
1236 count = omap2_mcspi_txrx_pio(spi, t);
1237
1238 if (count != t->len) {
1239 status = -EIO;
1240 goto out;
1241 }
1242 }
1243
1244 omap2_mcspi_set_enable(spi, 0);
1245
1246 if (mcspi->fifo_depth > 0)
1247 omap2_mcspi_set_fifo(spi, t, 0);
1248
1249out:
1250 /* Restore defaults if they were overriden */
1251 if (par_override) {
1252 par_override = 0;
1253 status = omap2_mcspi_setup_transfer(spi, NULL);
1254 }
1255
1256 if (cd && cd->cs_per_word) {
1257 chconf = mcspi->ctx.modulctrl;
1258 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1259 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1260 mcspi->ctx.modulctrl =
1261 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1262 }
1263
1264 omap2_mcspi_set_enable(spi, 0);
1265
1266 if (gpio_is_valid(spi->cs_gpio))
1267 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1268
1269 if (mcspi->fifo_depth > 0 && t)
1270 omap2_mcspi_set_fifo(spi, t, 0);
1271
1272 return status;
1273}
1274
1275static int omap2_mcspi_prepare_message(struct spi_master *master,
1276 struct spi_message *msg)
1277{
1278 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1279 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1280 struct omap2_mcspi_cs *cs;
1281
1282 /* Only a single channel can have the FORCE bit enabled
1283 * in its chconf0 register.
1284 * Scan all channels and disable them except the current one.
1285 * A FORCE can remain from a last transfer having cs_change enabled
1286 */
1287 list_for_each_entry(cs, &ctx->cs, node) {
1288 if (msg->spi->controller_state == cs)
1289 continue;
1290
1291 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1292 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1293 writel_relaxed(cs->chconf0,
1294 cs->base + OMAP2_MCSPI_CHCONF0);
1295 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1296 }
1297 }
1298
1299 return 0;
1300}
1301
1302static bool omap2_mcspi_can_dma(struct spi_master *master,
1303 struct spi_device *spi,
1304 struct spi_transfer *xfer)
1305{
1306 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1307 struct omap2_mcspi_dma *mcspi_dma =
1308 &mcspi->dma_channels[spi->chip_select];
1309
1310 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1311 return false;
1312
1313 if (spi_controller_is_slave(master))
1314 return true;
1315
1316 return (xfer->len >= DMA_MIN_BYTES);
1317}
1318
1319static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1320{
1321 struct spi_master *master = mcspi->master;
1322 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1323 int ret = 0;
1324
1325 ret = pm_runtime_get_sync(mcspi->dev);
1326 if (ret < 0) {
1327 pm_runtime_put_noidle(mcspi->dev);
1328
1329 return ret;
1330 }
1331
1332 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1333 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1334 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1335
1336 omap2_mcspi_set_mode(master);
1337 pm_runtime_mark_last_busy(mcspi->dev);
1338 pm_runtime_put_autosuspend(mcspi->dev);
1339 return 0;
1340}
1341
1342/*
1343 * When SPI wake up from off-mode, CS is in activate state. If it was in
1344 * inactive state when driver was suspend, then force it to inactive state at
1345 * wake up.
1346 */
1347static int omap_mcspi_runtime_resume(struct device *dev)
1348{
1349 struct spi_master *master = dev_get_drvdata(dev);
1350 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1351 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1352 struct omap2_mcspi_cs *cs;
1353
1354 /* McSPI: context restore */
1355 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1356 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1357
1358 list_for_each_entry(cs, &ctx->cs, node) {
1359 /*
1360 * We need to toggle CS state for OMAP take this
1361 * change in account.
1362 */
1363 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1364 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1365 writel_relaxed(cs->chconf0,
1366 cs->base + OMAP2_MCSPI_CHCONF0);
1367 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1368 writel_relaxed(cs->chconf0,
1369 cs->base + OMAP2_MCSPI_CHCONF0);
1370 } else {
1371 writel_relaxed(cs->chconf0,
1372 cs->base + OMAP2_MCSPI_CHCONF0);
1373 }
1374 }
1375
1376 return 0;
1377}
1378
1379static struct omap2_mcspi_platform_config omap2_pdata = {
1380 .regs_offset = 0,
1381};
1382
1383static struct omap2_mcspi_platform_config omap4_pdata = {
1384 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1385};
1386
1387static const struct of_device_id omap_mcspi_of_match[] = {
1388 {
1389 .compatible = "ti,omap2-mcspi",
1390 .data = &omap2_pdata,
1391 },
1392 {
1393 .compatible = "ti,omap4-mcspi",
1394 .data = &omap4_pdata,
1395 },
1396 { },
1397};
1398MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1399
1400static int omap2_mcspi_probe(struct platform_device *pdev)
1401{
1402 struct spi_master *master;
1403 const struct omap2_mcspi_platform_config *pdata;
1404 struct omap2_mcspi *mcspi;
1405 struct resource *r;
1406 int status = 0, i;
1407 u32 regs_offset = 0;
1408 struct device_node *node = pdev->dev.of_node;
1409 const struct of_device_id *match;
1410
1411 if (of_property_read_bool(node, "spi-slave"))
1412 master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1413 else
1414 master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1415 if (!master)
1416 return -ENOMEM;
1417
1418 /* the spi->mode bits understood by this driver: */
1419 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1420 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1421 master->setup = omap2_mcspi_setup;
1422 master->auto_runtime_pm = true;
1423 master->prepare_message = omap2_mcspi_prepare_message;
1424 master->can_dma = omap2_mcspi_can_dma;
1425 master->transfer_one = omap2_mcspi_transfer_one;
1426 master->set_cs = omap2_mcspi_set_cs;
1427 master->cleanup = omap2_mcspi_cleanup;
1428 master->slave_abort = omap2_mcspi_slave_abort;
1429 master->dev.of_node = node;
1430 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1431 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1432
1433 platform_set_drvdata(pdev, master);
1434
1435 mcspi = spi_master_get_devdata(master);
1436 mcspi->master = master;
1437
1438 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1439 if (match) {
1440 u32 num_cs = 1; /* default number of chipselect */
1441 pdata = match->data;
1442
1443 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1444 master->num_chipselect = num_cs;
1445 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1446 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1447 } else {
1448 pdata = dev_get_platdata(&pdev->dev);
1449 master->num_chipselect = pdata->num_cs;
1450 mcspi->pin_dir = pdata->pin_dir;
1451 }
1452 regs_offset = pdata->regs_offset;
1453
1454 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1455 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1456 if (IS_ERR(mcspi->base)) {
1457 status = PTR_ERR(mcspi->base);
1458 goto free_master;
1459 }
1460 mcspi->phys = r->start + regs_offset;
1461 mcspi->base += regs_offset;
1462
1463 mcspi->dev = &pdev->dev;
1464
1465 INIT_LIST_HEAD(&mcspi->ctx.cs);
1466
1467 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1468 sizeof(struct omap2_mcspi_dma),
1469 GFP_KERNEL);
1470 if (mcspi->dma_channels == NULL) {
1471 status = -ENOMEM;
1472 goto free_master;
1473 }
1474
1475 for (i = 0; i < master->num_chipselect; i++) {
1476 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1477 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1478 }
1479
1480 status = platform_get_irq(pdev, 0);
1481 if (status == -EPROBE_DEFER)
1482 goto free_master;
1483 if (status < 0) {
1484 dev_err(&pdev->dev, "no irq resource found\n");
1485 goto free_master;
1486 }
1487 init_completion(&mcspi->txdone);
1488 status = devm_request_irq(&pdev->dev, status,
1489 omap2_mcspi_irq_handler, 0, pdev->name,
1490 mcspi);
1491 if (status) {
1492 dev_err(&pdev->dev, "Cannot request IRQ");
1493 goto free_master;
1494 }
1495
1496 pm_runtime_use_autosuspend(&pdev->dev);
1497 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1498 pm_runtime_enable(&pdev->dev);
1499
1500 status = omap2_mcspi_controller_setup(mcspi);
1501 if (status < 0)
1502 goto disable_pm;
1503
1504 status = devm_spi_register_controller(&pdev->dev, master);
1505 if (status < 0)
1506 goto disable_pm;
1507
1508 return status;
1509
1510disable_pm:
1511 pm_runtime_dont_use_autosuspend(&pdev->dev);
1512 pm_runtime_put_sync(&pdev->dev);
1513 pm_runtime_disable(&pdev->dev);
1514free_master:
1515 spi_master_put(master);
1516 return status;
1517}
1518
1519static int omap2_mcspi_remove(struct platform_device *pdev)
1520{
1521 struct spi_master *master = platform_get_drvdata(pdev);
1522 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1523
1524 pm_runtime_dont_use_autosuspend(mcspi->dev);
1525 pm_runtime_put_sync(mcspi->dev);
1526 pm_runtime_disable(&pdev->dev);
1527
1528 return 0;
1529}
1530
1531/* work with hotplug and coldplug */
1532MODULE_ALIAS("platform:omap2_mcspi");
1533
1534static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1535{
1536 struct spi_master *master = dev_get_drvdata(dev);
1537 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1538 int error;
1539
1540 error = pinctrl_pm_select_sleep_state(dev);
1541 if (error)
1542 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1543 __func__, error);
1544
1545 error = spi_master_suspend(master);
1546 if (error)
1547 dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1548 __func__, error);
1549
1550 return pm_runtime_force_suspend(dev);
1551}
1552
1553static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1554{
1555 struct spi_master *master = dev_get_drvdata(dev);
1556 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1557 int error;
1558
1559 error = pinctrl_pm_select_default_state(dev);
1560 if (error)
1561 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1562 __func__, error);
1563
1564 error = spi_master_resume(master);
1565 if (error)
1566 dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1567 __func__, error);
1568
1569 return pm_runtime_force_resume(dev);
1570}
1571
1572static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1573 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1574 omap2_mcspi_resume)
1575 .runtime_resume = omap_mcspi_runtime_resume,
1576};
1577
1578static struct platform_driver omap2_mcspi_driver = {
1579 .driver = {
1580 .name = "omap2_mcspi",
1581 .pm = &omap2_mcspi_pm_ops,
1582 .of_match_table = omap_mcspi_of_match,
1583 },
1584 .probe = omap2_mcspi_probe,
1585 .remove = omap2_mcspi_remove,
1586};
1587
1588module_platform_driver(omap2_mcspi_driver);
1589MODULE_LICENSE("GPL");
1/*
2 * OMAP2 McSPI controller driver
3 *
4 * Copyright (C) 2005, 2006 Nokia Corporation
5 * Author: Samuel Ortiz <samuel.ortiz@nokia.com> and
6 * Juha Yrj�l� <juha.yrjola@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
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
19#include <linux/kernel.h>
20#include <linux/interrupt.h>
21#include <linux/module.h>
22#include <linux/device.h>
23#include <linux/delay.h>
24#include <linux/dma-mapping.h>
25#include <linux/dmaengine.h>
26#include <linux/pinctrl/consumer.h>
27#include <linux/platform_device.h>
28#include <linux/err.h>
29#include <linux/clk.h>
30#include <linux/io.h>
31#include <linux/slab.h>
32#include <linux/pm_runtime.h>
33#include <linux/of.h>
34#include <linux/of_device.h>
35#include <linux/gcd.h>
36
37#include <linux/spi/spi.h>
38#include <linux/gpio.h>
39
40#include <linux/platform_data/spi-omap2-mcspi.h>
41
42#define OMAP2_MCSPI_MAX_FREQ 48000000
43#define OMAP2_MCSPI_MAX_DIVIDER 4096
44#define OMAP2_MCSPI_MAX_FIFODEPTH 64
45#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
46#define SPI_AUTOSUSPEND_TIMEOUT 2000
47
48#define OMAP2_MCSPI_REVISION 0x00
49#define OMAP2_MCSPI_SYSSTATUS 0x14
50#define OMAP2_MCSPI_IRQSTATUS 0x18
51#define OMAP2_MCSPI_IRQENABLE 0x1c
52#define OMAP2_MCSPI_WAKEUPENABLE 0x20
53#define OMAP2_MCSPI_SYST 0x24
54#define OMAP2_MCSPI_MODULCTRL 0x28
55#define OMAP2_MCSPI_XFERLEVEL 0x7c
56
57/* per-channel banks, 0x14 bytes each, first is: */
58#define OMAP2_MCSPI_CHCONF0 0x2c
59#define OMAP2_MCSPI_CHSTAT0 0x30
60#define OMAP2_MCSPI_CHCTRL0 0x34
61#define OMAP2_MCSPI_TX0 0x38
62#define OMAP2_MCSPI_RX0 0x3c
63
64/* per-register bitmasks: */
65#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
66
67#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
68#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
69#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
70
71#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
72#define OMAP2_MCSPI_CHCONF_POL BIT(1)
73#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
74#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
75#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
76#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
77#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
78#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
79#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
80#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
81#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
82#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
83#define OMAP2_MCSPI_CHCONF_IS BIT(18)
84#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
85#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
86#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
87#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
88#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
89
90#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
91#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
92#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
93#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
94
95#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
96#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
97
98#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
99
100/* We have 2 DMA channels per CS, one for RX and one for TX */
101struct omap2_mcspi_dma {
102 struct dma_chan *dma_tx;
103 struct dma_chan *dma_rx;
104
105 struct completion dma_tx_completion;
106 struct completion dma_rx_completion;
107
108 char dma_rx_ch_name[14];
109 char dma_tx_ch_name[14];
110};
111
112/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
113 * cache operations; better heuristics consider wordsize and bitrate.
114 */
115#define DMA_MIN_BYTES 160
116
117
118/*
119 * Used for context save and restore, structure members to be updated whenever
120 * corresponding registers are modified.
121 */
122struct omap2_mcspi_regs {
123 u32 modulctrl;
124 u32 wakeupenable;
125 struct list_head cs;
126};
127
128struct omap2_mcspi {
129 struct spi_master *master;
130 /* Virtual base address of the controller */
131 void __iomem *base;
132 unsigned long phys;
133 /* SPI1 has 4 channels, while SPI2 has 2 */
134 struct omap2_mcspi_dma *dma_channels;
135 struct device *dev;
136 struct omap2_mcspi_regs ctx;
137 int fifo_depth;
138 unsigned int pin_dir:1;
139};
140
141struct omap2_mcspi_cs {
142 void __iomem *base;
143 unsigned long phys;
144 int word_len;
145 u16 mode;
146 struct list_head node;
147 /* Context save and restore shadow register */
148 u32 chconf0, chctrl0;
149};
150
151static inline void mcspi_write_reg(struct spi_master *master,
152 int idx, u32 val)
153{
154 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
155
156 writel_relaxed(val, mcspi->base + idx);
157}
158
159static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
160{
161 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
162
163 return readl_relaxed(mcspi->base + idx);
164}
165
166static inline void mcspi_write_cs_reg(const struct spi_device *spi,
167 int idx, u32 val)
168{
169 struct omap2_mcspi_cs *cs = spi->controller_state;
170
171 writel_relaxed(val, cs->base + idx);
172}
173
174static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
175{
176 struct omap2_mcspi_cs *cs = spi->controller_state;
177
178 return readl_relaxed(cs->base + idx);
179}
180
181static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
182{
183 struct omap2_mcspi_cs *cs = spi->controller_state;
184
185 return cs->chconf0;
186}
187
188static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
189{
190 struct omap2_mcspi_cs *cs = spi->controller_state;
191
192 cs->chconf0 = val;
193 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
194 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
195}
196
197static inline int mcspi_bytes_per_word(int word_len)
198{
199 if (word_len <= 8)
200 return 1;
201 else if (word_len <= 16)
202 return 2;
203 else /* word_len <= 32 */
204 return 4;
205}
206
207static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
208 int is_read, int enable)
209{
210 u32 l, rw;
211
212 l = mcspi_cached_chconf0(spi);
213
214 if (is_read) /* 1 is read, 0 write */
215 rw = OMAP2_MCSPI_CHCONF_DMAR;
216 else
217 rw = OMAP2_MCSPI_CHCONF_DMAW;
218
219 if (enable)
220 l |= rw;
221 else
222 l &= ~rw;
223
224 mcspi_write_chconf0(spi, l);
225}
226
227static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
228{
229 struct omap2_mcspi_cs *cs = spi->controller_state;
230 u32 l;
231
232 l = cs->chctrl0;
233 if (enable)
234 l |= OMAP2_MCSPI_CHCTRL_EN;
235 else
236 l &= ~OMAP2_MCSPI_CHCTRL_EN;
237 cs->chctrl0 = l;
238 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
239 /* Flash post-writes */
240 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
241}
242
243static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
244{
245 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
246 u32 l;
247
248 /* The controller handles the inverted chip selects
249 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
250 * the inversion from the core spi_set_cs function.
251 */
252 if (spi->mode & SPI_CS_HIGH)
253 enable = !enable;
254
255 if (spi->controller_state) {
256 int err = pm_runtime_get_sync(mcspi->dev);
257 if (err < 0) {
258 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
259 return;
260 }
261
262 l = mcspi_cached_chconf0(spi);
263
264 if (enable)
265 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
266 else
267 l |= OMAP2_MCSPI_CHCONF_FORCE;
268
269 mcspi_write_chconf0(spi, l);
270
271 pm_runtime_mark_last_busy(mcspi->dev);
272 pm_runtime_put_autosuspend(mcspi->dev);
273 }
274}
275
276static void omap2_mcspi_set_master_mode(struct spi_master *master)
277{
278 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
279 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
280 u32 l;
281
282 /*
283 * Setup when switching from (reset default) slave mode
284 * to single-channel master mode
285 */
286 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
287 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS);
288 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
289 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
290
291 ctx->modulctrl = l;
292}
293
294static void omap2_mcspi_set_fifo(const struct spi_device *spi,
295 struct spi_transfer *t, int enable)
296{
297 struct spi_master *master = spi->master;
298 struct omap2_mcspi_cs *cs = spi->controller_state;
299 struct omap2_mcspi *mcspi;
300 unsigned int wcnt;
301 int max_fifo_depth, fifo_depth, bytes_per_word;
302 u32 chconf, xferlevel;
303
304 mcspi = spi_master_get_devdata(master);
305
306 chconf = mcspi_cached_chconf0(spi);
307 if (enable) {
308 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
309 if (t->len % bytes_per_word != 0)
310 goto disable_fifo;
311
312 if (t->rx_buf != NULL && t->tx_buf != NULL)
313 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
314 else
315 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
316
317 fifo_depth = gcd(t->len, max_fifo_depth);
318 if (fifo_depth < 2 || fifo_depth % bytes_per_word != 0)
319 goto disable_fifo;
320
321 wcnt = t->len / bytes_per_word;
322 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
323 goto disable_fifo;
324
325 xferlevel = wcnt << 16;
326 if (t->rx_buf != NULL) {
327 chconf |= OMAP2_MCSPI_CHCONF_FFER;
328 xferlevel |= (fifo_depth - 1) << 8;
329 }
330 if (t->tx_buf != NULL) {
331 chconf |= OMAP2_MCSPI_CHCONF_FFET;
332 xferlevel |= fifo_depth - 1;
333 }
334
335 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
336 mcspi_write_chconf0(spi, chconf);
337 mcspi->fifo_depth = fifo_depth;
338
339 return;
340 }
341
342disable_fifo:
343 if (t->rx_buf != NULL)
344 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
345
346 if (t->tx_buf != NULL)
347 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
348
349 mcspi_write_chconf0(spi, chconf);
350 mcspi->fifo_depth = 0;
351}
352
353static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
354{
355 struct spi_master *spi_cntrl = mcspi->master;
356 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
357 struct omap2_mcspi_cs *cs;
358
359 /* McSPI: context restore */
360 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
361 mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
362
363 list_for_each_entry(cs, &ctx->cs, node)
364 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
365}
366
367static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
368{
369 unsigned long timeout;
370
371 timeout = jiffies + msecs_to_jiffies(1000);
372 while (!(readl_relaxed(reg) & bit)) {
373 if (time_after(jiffies, timeout)) {
374 if (!(readl_relaxed(reg) & bit))
375 return -ETIMEDOUT;
376 else
377 return 0;
378 }
379 cpu_relax();
380 }
381 return 0;
382}
383
384static void omap2_mcspi_rx_callback(void *data)
385{
386 struct spi_device *spi = data;
387 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
388 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
389
390 /* We must disable the DMA RX request */
391 omap2_mcspi_set_dma_req(spi, 1, 0);
392
393 complete(&mcspi_dma->dma_rx_completion);
394}
395
396static void omap2_mcspi_tx_callback(void *data)
397{
398 struct spi_device *spi = data;
399 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
400 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
401
402 /* We must disable the DMA TX request */
403 omap2_mcspi_set_dma_req(spi, 0, 0);
404
405 complete(&mcspi_dma->dma_tx_completion);
406}
407
408static void omap2_mcspi_tx_dma(struct spi_device *spi,
409 struct spi_transfer *xfer,
410 struct dma_slave_config cfg)
411{
412 struct omap2_mcspi *mcspi;
413 struct omap2_mcspi_dma *mcspi_dma;
414 unsigned int count;
415
416 mcspi = spi_master_get_devdata(spi->master);
417 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
418 count = xfer->len;
419
420 if (mcspi_dma->dma_tx) {
421 struct dma_async_tx_descriptor *tx;
422
423 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
424
425 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
426 xfer->tx_sg.nents,
427 DMA_MEM_TO_DEV,
428 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
429 if (tx) {
430 tx->callback = omap2_mcspi_tx_callback;
431 tx->callback_param = spi;
432 dmaengine_submit(tx);
433 } else {
434 /* FIXME: fall back to PIO? */
435 }
436 }
437 dma_async_issue_pending(mcspi_dma->dma_tx);
438 omap2_mcspi_set_dma_req(spi, 0, 1);
439
440}
441
442static unsigned
443omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
444 struct dma_slave_config cfg,
445 unsigned es)
446{
447 struct omap2_mcspi *mcspi;
448 struct omap2_mcspi_dma *mcspi_dma;
449 unsigned int count, transfer_reduction = 0;
450 struct scatterlist *sg_out[2];
451 int nb_sizes = 0, out_mapped_nents[2], ret, x;
452 size_t sizes[2];
453 u32 l;
454 int elements = 0;
455 int word_len, element_count;
456 struct omap2_mcspi_cs *cs = spi->controller_state;
457 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
458
459 mcspi = spi_master_get_devdata(spi->master);
460 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
461 count = xfer->len;
462
463 /*
464 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
465 * it mentions reducing DMA transfer length by one element in master
466 * normal mode.
467 */
468 if (mcspi->fifo_depth == 0)
469 transfer_reduction = es;
470
471 word_len = cs->word_len;
472 l = mcspi_cached_chconf0(spi);
473
474 if (word_len <= 8)
475 element_count = count;
476 else if (word_len <= 16)
477 element_count = count >> 1;
478 else /* word_len <= 32 */
479 element_count = count >> 2;
480
481 if (mcspi_dma->dma_rx) {
482 struct dma_async_tx_descriptor *tx;
483
484 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
485
486 /*
487 * Reduce DMA transfer length by one more if McSPI is
488 * configured in turbo mode.
489 */
490 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
491 transfer_reduction += es;
492
493 if (transfer_reduction) {
494 /* Split sgl into two. The second sgl won't be used. */
495 sizes[0] = count - transfer_reduction;
496 sizes[1] = transfer_reduction;
497 nb_sizes = 2;
498 } else {
499 /*
500 * Don't bother splitting the sgl. This essentially
501 * clones the original sgl.
502 */
503 sizes[0] = count;
504 nb_sizes = 1;
505 }
506
507 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents,
508 0, nb_sizes,
509 sizes,
510 sg_out, out_mapped_nents,
511 GFP_KERNEL);
512
513 if (ret < 0) {
514 dev_err(&spi->dev, "sg_split failed\n");
515 return 0;
516 }
517
518 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx,
519 sg_out[0],
520 out_mapped_nents[0],
521 DMA_DEV_TO_MEM,
522 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
523 if (tx) {
524 tx->callback = omap2_mcspi_rx_callback;
525 tx->callback_param = spi;
526 dmaengine_submit(tx);
527 } else {
528 /* FIXME: fall back to PIO? */
529 }
530 }
531
532 dma_async_issue_pending(mcspi_dma->dma_rx);
533 omap2_mcspi_set_dma_req(spi, 1, 1);
534
535 wait_for_completion(&mcspi_dma->dma_rx_completion);
536
537 for (x = 0; x < nb_sizes; x++)
538 kfree(sg_out[x]);
539
540 if (mcspi->fifo_depth > 0)
541 return count;
542
543 /*
544 * Due to the DMA transfer length reduction the missing bytes must
545 * be read manually to receive all of the expected data.
546 */
547 omap2_mcspi_set_enable(spi, 0);
548
549 elements = element_count - 1;
550
551 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
552 elements--;
553
554 if (!mcspi_wait_for_reg_bit(chstat_reg,
555 OMAP2_MCSPI_CHSTAT_RXS)) {
556 u32 w;
557
558 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
559 if (word_len <= 8)
560 ((u8 *)xfer->rx_buf)[elements++] = w;
561 else if (word_len <= 16)
562 ((u16 *)xfer->rx_buf)[elements++] = w;
563 else /* word_len <= 32 */
564 ((u32 *)xfer->rx_buf)[elements++] = w;
565 } else {
566 int bytes_per_word = mcspi_bytes_per_word(word_len);
567 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
568 count -= (bytes_per_word << 1);
569 omap2_mcspi_set_enable(spi, 1);
570 return count;
571 }
572 }
573 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
574 u32 w;
575
576 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
577 if (word_len <= 8)
578 ((u8 *)xfer->rx_buf)[elements] = w;
579 else if (word_len <= 16)
580 ((u16 *)xfer->rx_buf)[elements] = w;
581 else /* word_len <= 32 */
582 ((u32 *)xfer->rx_buf)[elements] = w;
583 } else {
584 dev_err(&spi->dev, "DMA RX last word empty\n");
585 count -= mcspi_bytes_per_word(word_len);
586 }
587 omap2_mcspi_set_enable(spi, 1);
588 return count;
589}
590
591static unsigned
592omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
593{
594 struct omap2_mcspi *mcspi;
595 struct omap2_mcspi_cs *cs = spi->controller_state;
596 struct omap2_mcspi_dma *mcspi_dma;
597 unsigned int count;
598 u32 l;
599 u8 *rx;
600 const u8 *tx;
601 struct dma_slave_config cfg;
602 enum dma_slave_buswidth width;
603 unsigned es;
604 u32 burst;
605 void __iomem *chstat_reg;
606 void __iomem *irqstat_reg;
607 int wait_res;
608
609 mcspi = spi_master_get_devdata(spi->master);
610 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
611 l = mcspi_cached_chconf0(spi);
612
613
614 if (cs->word_len <= 8) {
615 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
616 es = 1;
617 } else if (cs->word_len <= 16) {
618 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
619 es = 2;
620 } else {
621 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
622 es = 4;
623 }
624
625 count = xfer->len;
626 burst = 1;
627
628 if (mcspi->fifo_depth > 0) {
629 if (count > mcspi->fifo_depth)
630 burst = mcspi->fifo_depth / es;
631 else
632 burst = count / es;
633 }
634
635 memset(&cfg, 0, sizeof(cfg));
636 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
637 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
638 cfg.src_addr_width = width;
639 cfg.dst_addr_width = width;
640 cfg.src_maxburst = burst;
641 cfg.dst_maxburst = burst;
642
643 rx = xfer->rx_buf;
644 tx = xfer->tx_buf;
645
646 if (tx != NULL)
647 omap2_mcspi_tx_dma(spi, xfer, cfg);
648
649 if (rx != NULL)
650 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
651
652 if (tx != NULL) {
653 wait_for_completion(&mcspi_dma->dma_tx_completion);
654
655 if (mcspi->fifo_depth > 0) {
656 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
657
658 if (mcspi_wait_for_reg_bit(irqstat_reg,
659 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
660 dev_err(&spi->dev, "EOW timed out\n");
661
662 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
663 OMAP2_MCSPI_IRQSTATUS_EOW);
664 }
665
666 /* for TX_ONLY mode, be sure all words have shifted out */
667 if (rx == NULL) {
668 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
669 if (mcspi->fifo_depth > 0) {
670 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
671 OMAP2_MCSPI_CHSTAT_TXFFE);
672 if (wait_res < 0)
673 dev_err(&spi->dev, "TXFFE timed out\n");
674 } else {
675 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
676 OMAP2_MCSPI_CHSTAT_TXS);
677 if (wait_res < 0)
678 dev_err(&spi->dev, "TXS timed out\n");
679 }
680 if (wait_res >= 0 &&
681 (mcspi_wait_for_reg_bit(chstat_reg,
682 OMAP2_MCSPI_CHSTAT_EOT) < 0))
683 dev_err(&spi->dev, "EOT timed out\n");
684 }
685 }
686 return count;
687}
688
689static unsigned
690omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
691{
692 struct omap2_mcspi *mcspi;
693 struct omap2_mcspi_cs *cs = spi->controller_state;
694 unsigned int count, c;
695 u32 l;
696 void __iomem *base = cs->base;
697 void __iomem *tx_reg;
698 void __iomem *rx_reg;
699 void __iomem *chstat_reg;
700 int word_len;
701
702 mcspi = spi_master_get_devdata(spi->master);
703 count = xfer->len;
704 c = count;
705 word_len = cs->word_len;
706
707 l = mcspi_cached_chconf0(spi);
708
709 /* We store the pre-calculated register addresses on stack to speed
710 * up the transfer loop. */
711 tx_reg = base + OMAP2_MCSPI_TX0;
712 rx_reg = base + OMAP2_MCSPI_RX0;
713 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
714
715 if (c < (word_len>>3))
716 return 0;
717
718 if (word_len <= 8) {
719 u8 *rx;
720 const u8 *tx;
721
722 rx = xfer->rx_buf;
723 tx = xfer->tx_buf;
724
725 do {
726 c -= 1;
727 if (tx != NULL) {
728 if (mcspi_wait_for_reg_bit(chstat_reg,
729 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
730 dev_err(&spi->dev, "TXS timed out\n");
731 goto out;
732 }
733 dev_vdbg(&spi->dev, "write-%d %02x\n",
734 word_len, *tx);
735 writel_relaxed(*tx++, tx_reg);
736 }
737 if (rx != NULL) {
738 if (mcspi_wait_for_reg_bit(chstat_reg,
739 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
740 dev_err(&spi->dev, "RXS timed out\n");
741 goto out;
742 }
743
744 if (c == 1 && tx == NULL &&
745 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
746 omap2_mcspi_set_enable(spi, 0);
747 *rx++ = readl_relaxed(rx_reg);
748 dev_vdbg(&spi->dev, "read-%d %02x\n",
749 word_len, *(rx - 1));
750 if (mcspi_wait_for_reg_bit(chstat_reg,
751 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
752 dev_err(&spi->dev,
753 "RXS timed out\n");
754 goto out;
755 }
756 c = 0;
757 } else if (c == 0 && tx == NULL) {
758 omap2_mcspi_set_enable(spi, 0);
759 }
760
761 *rx++ = readl_relaxed(rx_reg);
762 dev_vdbg(&spi->dev, "read-%d %02x\n",
763 word_len, *(rx - 1));
764 }
765 } while (c);
766 } else if (word_len <= 16) {
767 u16 *rx;
768 const u16 *tx;
769
770 rx = xfer->rx_buf;
771 tx = xfer->tx_buf;
772 do {
773 c -= 2;
774 if (tx != NULL) {
775 if (mcspi_wait_for_reg_bit(chstat_reg,
776 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
777 dev_err(&spi->dev, "TXS timed out\n");
778 goto out;
779 }
780 dev_vdbg(&spi->dev, "write-%d %04x\n",
781 word_len, *tx);
782 writel_relaxed(*tx++, tx_reg);
783 }
784 if (rx != NULL) {
785 if (mcspi_wait_for_reg_bit(chstat_reg,
786 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
787 dev_err(&spi->dev, "RXS timed out\n");
788 goto out;
789 }
790
791 if (c == 2 && tx == NULL &&
792 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
793 omap2_mcspi_set_enable(spi, 0);
794 *rx++ = readl_relaxed(rx_reg);
795 dev_vdbg(&spi->dev, "read-%d %04x\n",
796 word_len, *(rx - 1));
797 if (mcspi_wait_for_reg_bit(chstat_reg,
798 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
799 dev_err(&spi->dev,
800 "RXS timed out\n");
801 goto out;
802 }
803 c = 0;
804 } else if (c == 0 && tx == NULL) {
805 omap2_mcspi_set_enable(spi, 0);
806 }
807
808 *rx++ = readl_relaxed(rx_reg);
809 dev_vdbg(&spi->dev, "read-%d %04x\n",
810 word_len, *(rx - 1));
811 }
812 } while (c >= 2);
813 } else if (word_len <= 32) {
814 u32 *rx;
815 const u32 *tx;
816
817 rx = xfer->rx_buf;
818 tx = xfer->tx_buf;
819 do {
820 c -= 4;
821 if (tx != NULL) {
822 if (mcspi_wait_for_reg_bit(chstat_reg,
823 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
824 dev_err(&spi->dev, "TXS timed out\n");
825 goto out;
826 }
827 dev_vdbg(&spi->dev, "write-%d %08x\n",
828 word_len, *tx);
829 writel_relaxed(*tx++, tx_reg);
830 }
831 if (rx != NULL) {
832 if (mcspi_wait_for_reg_bit(chstat_reg,
833 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
834 dev_err(&spi->dev, "RXS timed out\n");
835 goto out;
836 }
837
838 if (c == 4 && tx == NULL &&
839 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
840 omap2_mcspi_set_enable(spi, 0);
841 *rx++ = readl_relaxed(rx_reg);
842 dev_vdbg(&spi->dev, "read-%d %08x\n",
843 word_len, *(rx - 1));
844 if (mcspi_wait_for_reg_bit(chstat_reg,
845 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
846 dev_err(&spi->dev,
847 "RXS timed out\n");
848 goto out;
849 }
850 c = 0;
851 } else if (c == 0 && tx == NULL) {
852 omap2_mcspi_set_enable(spi, 0);
853 }
854
855 *rx++ = readl_relaxed(rx_reg);
856 dev_vdbg(&spi->dev, "read-%d %08x\n",
857 word_len, *(rx - 1));
858 }
859 } while (c >= 4);
860 }
861
862 /* for TX_ONLY mode, be sure all words have shifted out */
863 if (xfer->rx_buf == NULL) {
864 if (mcspi_wait_for_reg_bit(chstat_reg,
865 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
866 dev_err(&spi->dev, "TXS timed out\n");
867 } else if (mcspi_wait_for_reg_bit(chstat_reg,
868 OMAP2_MCSPI_CHSTAT_EOT) < 0)
869 dev_err(&spi->dev, "EOT timed out\n");
870
871 /* disable chan to purge rx datas received in TX_ONLY transfer,
872 * otherwise these rx datas will affect the direct following
873 * RX_ONLY transfer.
874 */
875 omap2_mcspi_set_enable(spi, 0);
876 }
877out:
878 omap2_mcspi_set_enable(spi, 1);
879 return count - c;
880}
881
882static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
883{
884 u32 div;
885
886 for (div = 0; div < 15; div++)
887 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
888 return div;
889
890 return 15;
891}
892
893/* called only when no transfer is active to this device */
894static int omap2_mcspi_setup_transfer(struct spi_device *spi,
895 struct spi_transfer *t)
896{
897 struct omap2_mcspi_cs *cs = spi->controller_state;
898 struct omap2_mcspi *mcspi;
899 struct spi_master *spi_cntrl;
900 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
901 u8 word_len = spi->bits_per_word;
902 u32 speed_hz = spi->max_speed_hz;
903
904 mcspi = spi_master_get_devdata(spi->master);
905 spi_cntrl = mcspi->master;
906
907 if (t != NULL && t->bits_per_word)
908 word_len = t->bits_per_word;
909
910 cs->word_len = word_len;
911
912 if (t && t->speed_hz)
913 speed_hz = t->speed_hz;
914
915 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
916 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
917 clkd = omap2_mcspi_calc_divisor(speed_hz);
918 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
919 clkg = 0;
920 } else {
921 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
922 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
923 clkd = (div - 1) & 0xf;
924 extclk = (div - 1) >> 4;
925 clkg = OMAP2_MCSPI_CHCONF_CLKG;
926 }
927
928 l = mcspi_cached_chconf0(spi);
929
930 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
931 * REVISIT: this controller could support SPI_3WIRE mode.
932 */
933 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
934 l &= ~OMAP2_MCSPI_CHCONF_IS;
935 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
936 l |= OMAP2_MCSPI_CHCONF_DPE0;
937 } else {
938 l |= OMAP2_MCSPI_CHCONF_IS;
939 l |= OMAP2_MCSPI_CHCONF_DPE1;
940 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
941 }
942
943 /* wordlength */
944 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
945 l |= (word_len - 1) << 7;
946
947 /* set chipselect polarity; manage with FORCE */
948 if (!(spi->mode & SPI_CS_HIGH))
949 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
950 else
951 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
952
953 /* set clock divisor */
954 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
955 l |= clkd << 2;
956
957 /* set clock granularity */
958 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
959 l |= clkg;
960 if (clkg) {
961 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
962 cs->chctrl0 |= extclk << 8;
963 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
964 }
965
966 /* set SPI mode 0..3 */
967 if (spi->mode & SPI_CPOL)
968 l |= OMAP2_MCSPI_CHCONF_POL;
969 else
970 l &= ~OMAP2_MCSPI_CHCONF_POL;
971 if (spi->mode & SPI_CPHA)
972 l |= OMAP2_MCSPI_CHCONF_PHA;
973 else
974 l &= ~OMAP2_MCSPI_CHCONF_PHA;
975
976 mcspi_write_chconf0(spi, l);
977
978 cs->mode = spi->mode;
979
980 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
981 speed_hz,
982 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
983 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
984
985 return 0;
986}
987
988/*
989 * Note that we currently allow DMA only if we get a channel
990 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
991 */
992static int omap2_mcspi_request_dma(struct spi_device *spi)
993{
994 struct spi_master *master = spi->master;
995 struct omap2_mcspi *mcspi;
996 struct omap2_mcspi_dma *mcspi_dma;
997 int ret = 0;
998
999 mcspi = spi_master_get_devdata(master);
1000 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1001
1002 init_completion(&mcspi_dma->dma_rx_completion);
1003 init_completion(&mcspi_dma->dma_tx_completion);
1004
1005 mcspi_dma->dma_rx = dma_request_chan(&master->dev,
1006 mcspi_dma->dma_rx_ch_name);
1007 if (IS_ERR(mcspi_dma->dma_rx)) {
1008 ret = PTR_ERR(mcspi_dma->dma_rx);
1009 mcspi_dma->dma_rx = NULL;
1010 goto no_dma;
1011 }
1012
1013 mcspi_dma->dma_tx = dma_request_chan(&master->dev,
1014 mcspi_dma->dma_tx_ch_name);
1015 if (IS_ERR(mcspi_dma->dma_tx)) {
1016 ret = PTR_ERR(mcspi_dma->dma_tx);
1017 mcspi_dma->dma_tx = NULL;
1018 dma_release_channel(mcspi_dma->dma_rx);
1019 mcspi_dma->dma_rx = NULL;
1020 }
1021
1022no_dma:
1023 return ret;
1024}
1025
1026static int omap2_mcspi_setup(struct spi_device *spi)
1027{
1028 int ret;
1029 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1030 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1031 struct omap2_mcspi_dma *mcspi_dma;
1032 struct omap2_mcspi_cs *cs = spi->controller_state;
1033
1034 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1035
1036 if (!cs) {
1037 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1038 if (!cs)
1039 return -ENOMEM;
1040 cs->base = mcspi->base + spi->chip_select * 0x14;
1041 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1042 cs->mode = 0;
1043 cs->chconf0 = 0;
1044 cs->chctrl0 = 0;
1045 spi->controller_state = cs;
1046 /* Link this to context save list */
1047 list_add_tail(&cs->node, &ctx->cs);
1048
1049 if (gpio_is_valid(spi->cs_gpio)) {
1050 ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
1051 if (ret) {
1052 dev_err(&spi->dev, "failed to request gpio\n");
1053 return ret;
1054 }
1055 gpio_direction_output(spi->cs_gpio,
1056 !(spi->mode & SPI_CS_HIGH));
1057 }
1058 }
1059
1060 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) {
1061 ret = omap2_mcspi_request_dma(spi);
1062 if (ret)
1063 dev_warn(&spi->dev, "not using DMA for McSPI (%d)\n",
1064 ret);
1065 }
1066
1067 ret = pm_runtime_get_sync(mcspi->dev);
1068 if (ret < 0)
1069 return ret;
1070
1071 ret = omap2_mcspi_setup_transfer(spi, NULL);
1072 pm_runtime_mark_last_busy(mcspi->dev);
1073 pm_runtime_put_autosuspend(mcspi->dev);
1074
1075 return ret;
1076}
1077
1078static void omap2_mcspi_cleanup(struct spi_device *spi)
1079{
1080 struct omap2_mcspi *mcspi;
1081 struct omap2_mcspi_dma *mcspi_dma;
1082 struct omap2_mcspi_cs *cs;
1083
1084 mcspi = spi_master_get_devdata(spi->master);
1085
1086 if (spi->controller_state) {
1087 /* Unlink controller state from context save list */
1088 cs = spi->controller_state;
1089 list_del(&cs->node);
1090
1091 kfree(cs);
1092 }
1093
1094 if (spi->chip_select < spi->master->num_chipselect) {
1095 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
1096
1097 if (mcspi_dma->dma_rx) {
1098 dma_release_channel(mcspi_dma->dma_rx);
1099 mcspi_dma->dma_rx = NULL;
1100 }
1101 if (mcspi_dma->dma_tx) {
1102 dma_release_channel(mcspi_dma->dma_tx);
1103 mcspi_dma->dma_tx = NULL;
1104 }
1105 }
1106
1107 if (gpio_is_valid(spi->cs_gpio))
1108 gpio_free(spi->cs_gpio);
1109}
1110
1111static int omap2_mcspi_transfer_one(struct spi_master *master,
1112 struct spi_device *spi,
1113 struct spi_transfer *t)
1114{
1115
1116 /* We only enable one channel at a time -- the one whose message is
1117 * -- although this controller would gladly
1118 * arbitrate among multiple channels. This corresponds to "single
1119 * channel" master mode. As a side effect, we need to manage the
1120 * chipselect with the FORCE bit ... CS != channel enable.
1121 */
1122
1123 struct omap2_mcspi *mcspi;
1124 struct omap2_mcspi_dma *mcspi_dma;
1125 struct omap2_mcspi_cs *cs;
1126 struct omap2_mcspi_device_config *cd;
1127 int par_override = 0;
1128 int status = 0;
1129 u32 chconf;
1130
1131 mcspi = spi_master_get_devdata(master);
1132 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1133 cs = spi->controller_state;
1134 cd = spi->controller_data;
1135
1136 /*
1137 * The slave driver could have changed spi->mode in which case
1138 * it will be different from cs->mode (the current hardware setup).
1139 * If so, set par_override (even though its not a parity issue) so
1140 * omap2_mcspi_setup_transfer will be called to configure the hardware
1141 * with the correct mode on the first iteration of the loop below.
1142 */
1143 if (spi->mode != cs->mode)
1144 par_override = 1;
1145
1146 omap2_mcspi_set_enable(spi, 0);
1147
1148 if (gpio_is_valid(spi->cs_gpio))
1149 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1150
1151 if (par_override ||
1152 (t->speed_hz != spi->max_speed_hz) ||
1153 (t->bits_per_word != spi->bits_per_word)) {
1154 par_override = 1;
1155 status = omap2_mcspi_setup_transfer(spi, t);
1156 if (status < 0)
1157 goto out;
1158 if (t->speed_hz == spi->max_speed_hz &&
1159 t->bits_per_word == spi->bits_per_word)
1160 par_override = 0;
1161 }
1162 if (cd && cd->cs_per_word) {
1163 chconf = mcspi->ctx.modulctrl;
1164 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1165 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1166 mcspi->ctx.modulctrl =
1167 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1168 }
1169
1170 chconf = mcspi_cached_chconf0(spi);
1171 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1172 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1173
1174 if (t->tx_buf == NULL)
1175 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1176 else if (t->rx_buf == NULL)
1177 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1178
1179 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1180 /* Turbo mode is for more than one word */
1181 if (t->len > ((cs->word_len + 7) >> 3))
1182 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1183 }
1184
1185 mcspi_write_chconf0(spi, chconf);
1186
1187 if (t->len) {
1188 unsigned count;
1189
1190 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1191 master->cur_msg_mapped &&
1192 master->can_dma(master, spi, t))
1193 omap2_mcspi_set_fifo(spi, t, 1);
1194
1195 omap2_mcspi_set_enable(spi, 1);
1196
1197 /* RX_ONLY mode needs dummy data in TX reg */
1198 if (t->tx_buf == NULL)
1199 writel_relaxed(0, cs->base
1200 + OMAP2_MCSPI_TX0);
1201
1202 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1203 master->cur_msg_mapped &&
1204 master->can_dma(master, spi, t))
1205 count = omap2_mcspi_txrx_dma(spi, t);
1206 else
1207 count = omap2_mcspi_txrx_pio(spi, t);
1208
1209 if (count != t->len) {
1210 status = -EIO;
1211 goto out;
1212 }
1213 }
1214
1215 omap2_mcspi_set_enable(spi, 0);
1216
1217 if (mcspi->fifo_depth > 0)
1218 omap2_mcspi_set_fifo(spi, t, 0);
1219
1220out:
1221 /* Restore defaults if they were overriden */
1222 if (par_override) {
1223 par_override = 0;
1224 status = omap2_mcspi_setup_transfer(spi, NULL);
1225 }
1226
1227 if (cd && cd->cs_per_word) {
1228 chconf = mcspi->ctx.modulctrl;
1229 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1230 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1231 mcspi->ctx.modulctrl =
1232 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1233 }
1234
1235 omap2_mcspi_set_enable(spi, 0);
1236
1237 if (gpio_is_valid(spi->cs_gpio))
1238 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1239
1240 if (mcspi->fifo_depth > 0 && t)
1241 omap2_mcspi_set_fifo(spi, t, 0);
1242
1243 return status;
1244}
1245
1246static int omap2_mcspi_prepare_message(struct spi_master *master,
1247 struct spi_message *msg)
1248{
1249 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1250 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1251 struct omap2_mcspi_cs *cs;
1252
1253 /* Only a single channel can have the FORCE bit enabled
1254 * in its chconf0 register.
1255 * Scan all channels and disable them except the current one.
1256 * A FORCE can remain from a last transfer having cs_change enabled
1257 */
1258 list_for_each_entry(cs, &ctx->cs, node) {
1259 if (msg->spi->controller_state == cs)
1260 continue;
1261
1262 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1263 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1264 writel_relaxed(cs->chconf0,
1265 cs->base + OMAP2_MCSPI_CHCONF0);
1266 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1267 }
1268 }
1269
1270 return 0;
1271}
1272
1273static bool omap2_mcspi_can_dma(struct spi_master *master,
1274 struct spi_device *spi,
1275 struct spi_transfer *xfer)
1276{
1277 return (xfer->len >= DMA_MIN_BYTES);
1278}
1279
1280static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi)
1281{
1282 struct spi_master *master = mcspi->master;
1283 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1284 int ret = 0;
1285
1286 ret = pm_runtime_get_sync(mcspi->dev);
1287 if (ret < 0)
1288 return ret;
1289
1290 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1291 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1292 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1293
1294 omap2_mcspi_set_master_mode(master);
1295 pm_runtime_mark_last_busy(mcspi->dev);
1296 pm_runtime_put_autosuspend(mcspi->dev);
1297 return 0;
1298}
1299
1300static int omap_mcspi_runtime_resume(struct device *dev)
1301{
1302 struct omap2_mcspi *mcspi;
1303 struct spi_master *master;
1304
1305 master = dev_get_drvdata(dev);
1306 mcspi = spi_master_get_devdata(master);
1307 omap2_mcspi_restore_ctx(mcspi);
1308
1309 return 0;
1310}
1311
1312static struct omap2_mcspi_platform_config omap2_pdata = {
1313 .regs_offset = 0,
1314};
1315
1316static struct omap2_mcspi_platform_config omap4_pdata = {
1317 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1318};
1319
1320static const struct of_device_id omap_mcspi_of_match[] = {
1321 {
1322 .compatible = "ti,omap2-mcspi",
1323 .data = &omap2_pdata,
1324 },
1325 {
1326 .compatible = "ti,omap4-mcspi",
1327 .data = &omap4_pdata,
1328 },
1329 { },
1330};
1331MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1332
1333static int omap2_mcspi_probe(struct platform_device *pdev)
1334{
1335 struct spi_master *master;
1336 const struct omap2_mcspi_platform_config *pdata;
1337 struct omap2_mcspi *mcspi;
1338 struct resource *r;
1339 int status = 0, i;
1340 u32 regs_offset = 0;
1341 struct device_node *node = pdev->dev.of_node;
1342 const struct of_device_id *match;
1343
1344 master = spi_alloc_master(&pdev->dev, sizeof *mcspi);
1345 if (master == NULL) {
1346 dev_dbg(&pdev->dev, "master allocation failed\n");
1347 return -ENOMEM;
1348 }
1349
1350 /* the spi->mode bits understood by this driver: */
1351 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1352 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1353 master->setup = omap2_mcspi_setup;
1354 master->auto_runtime_pm = true;
1355 master->prepare_message = omap2_mcspi_prepare_message;
1356 master->can_dma = omap2_mcspi_can_dma;
1357 master->transfer_one = omap2_mcspi_transfer_one;
1358 master->set_cs = omap2_mcspi_set_cs;
1359 master->cleanup = omap2_mcspi_cleanup;
1360 master->dev.of_node = node;
1361 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1362 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1363
1364 platform_set_drvdata(pdev, master);
1365
1366 mcspi = spi_master_get_devdata(master);
1367 mcspi->master = master;
1368
1369 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1370 if (match) {
1371 u32 num_cs = 1; /* default number of chipselect */
1372 pdata = match->data;
1373
1374 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1375 master->num_chipselect = num_cs;
1376 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1377 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1378 } else {
1379 pdata = dev_get_platdata(&pdev->dev);
1380 master->num_chipselect = pdata->num_cs;
1381 mcspi->pin_dir = pdata->pin_dir;
1382 }
1383 regs_offset = pdata->regs_offset;
1384
1385 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1386 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1387 if (IS_ERR(mcspi->base)) {
1388 status = PTR_ERR(mcspi->base);
1389 goto free_master;
1390 }
1391 mcspi->phys = r->start + regs_offset;
1392 mcspi->base += regs_offset;
1393
1394 mcspi->dev = &pdev->dev;
1395
1396 INIT_LIST_HEAD(&mcspi->ctx.cs);
1397
1398 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1399 sizeof(struct omap2_mcspi_dma),
1400 GFP_KERNEL);
1401 if (mcspi->dma_channels == NULL) {
1402 status = -ENOMEM;
1403 goto free_master;
1404 }
1405
1406 for (i = 0; i < master->num_chipselect; i++) {
1407 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1408 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1409 }
1410
1411 pm_runtime_use_autosuspend(&pdev->dev);
1412 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1413 pm_runtime_enable(&pdev->dev);
1414
1415 status = omap2_mcspi_master_setup(mcspi);
1416 if (status < 0)
1417 goto disable_pm;
1418
1419 status = devm_spi_register_master(&pdev->dev, master);
1420 if (status < 0)
1421 goto disable_pm;
1422
1423 return status;
1424
1425disable_pm:
1426 pm_runtime_dont_use_autosuspend(&pdev->dev);
1427 pm_runtime_put_sync(&pdev->dev);
1428 pm_runtime_disable(&pdev->dev);
1429free_master:
1430 spi_master_put(master);
1431 return status;
1432}
1433
1434static int omap2_mcspi_remove(struct platform_device *pdev)
1435{
1436 struct spi_master *master = platform_get_drvdata(pdev);
1437 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1438
1439 pm_runtime_dont_use_autosuspend(mcspi->dev);
1440 pm_runtime_put_sync(mcspi->dev);
1441 pm_runtime_disable(&pdev->dev);
1442
1443 return 0;
1444}
1445
1446/* work with hotplug and coldplug */
1447MODULE_ALIAS("platform:omap2_mcspi");
1448
1449#ifdef CONFIG_SUSPEND
1450/*
1451 * When SPI wake up from off-mode, CS is in activate state. If it was in
1452 * unactive state when driver was suspend, then force it to unactive state at
1453 * wake up.
1454 */
1455static int omap2_mcspi_resume(struct device *dev)
1456{
1457 struct spi_master *master = dev_get_drvdata(dev);
1458 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1459 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1460 struct omap2_mcspi_cs *cs;
1461
1462 pm_runtime_get_sync(mcspi->dev);
1463 list_for_each_entry(cs, &ctx->cs, node) {
1464 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1465 /*
1466 * We need to toggle CS state for OMAP take this
1467 * change in account.
1468 */
1469 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1470 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1471 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1472 writel_relaxed(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
1473 }
1474 }
1475 pm_runtime_mark_last_busy(mcspi->dev);
1476 pm_runtime_put_autosuspend(mcspi->dev);
1477
1478 return pinctrl_pm_select_default_state(dev);
1479}
1480
1481static int omap2_mcspi_suspend(struct device *dev)
1482{
1483 return pinctrl_pm_select_sleep_state(dev);
1484}
1485
1486#else
1487#define omap2_mcspi_suspend NULL
1488#define omap2_mcspi_resume NULL
1489#endif
1490
1491static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1492 .resume = omap2_mcspi_resume,
1493 .suspend = omap2_mcspi_suspend,
1494 .runtime_resume = omap_mcspi_runtime_resume,
1495};
1496
1497static struct platform_driver omap2_mcspi_driver = {
1498 .driver = {
1499 .name = "omap2_mcspi",
1500 .pm = &omap2_mcspi_pm_ops,
1501 .of_match_table = omap_mcspi_of_match,
1502 },
1503 .probe = omap2_mcspi_probe,
1504 .remove = omap2_mcspi_remove,
1505};
1506
1507module_platform_driver(omap2_mcspi_driver);
1508MODULE_LICENSE("GPL");