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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
31#include <linux/platform_data/spi-omap2-mcspi.h>
32
33#define OMAP2_MCSPI_MAX_FREQ 48000000
34#define OMAP2_MCSPI_MAX_DIVIDER 4096
35#define OMAP2_MCSPI_MAX_FIFODEPTH 64
36#define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
37#define SPI_AUTOSUSPEND_TIMEOUT 2000
38
39#define OMAP2_MCSPI_REVISION 0x00
40#define OMAP2_MCSPI_SYSSTATUS 0x14
41#define OMAP2_MCSPI_IRQSTATUS 0x18
42#define OMAP2_MCSPI_IRQENABLE 0x1c
43#define OMAP2_MCSPI_WAKEUPENABLE 0x20
44#define OMAP2_MCSPI_SYST 0x24
45#define OMAP2_MCSPI_MODULCTRL 0x28
46#define OMAP2_MCSPI_XFERLEVEL 0x7c
47
48/* per-channel banks, 0x14 bytes each, first is: */
49#define OMAP2_MCSPI_CHCONF0 0x2c
50#define OMAP2_MCSPI_CHSTAT0 0x30
51#define OMAP2_MCSPI_CHCTRL0 0x34
52#define OMAP2_MCSPI_TX0 0x38
53#define OMAP2_MCSPI_RX0 0x3c
54
55/* per-register bitmasks: */
56#define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
57
58#define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
59#define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
60#define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
61
62#define OMAP2_MCSPI_CHCONF_PHA BIT(0)
63#define OMAP2_MCSPI_CHCONF_POL BIT(1)
64#define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
65#define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
66#define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
67#define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
68#define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
69#define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
70#define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
71#define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
72#define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
73#define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
74#define OMAP2_MCSPI_CHCONF_IS BIT(18)
75#define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
76#define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
77#define OMAP2_MCSPI_CHCONF_FFET BIT(27)
78#define OMAP2_MCSPI_CHCONF_FFER BIT(28)
79#define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
80
81#define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
82#define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
83#define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
84#define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
85
86#define OMAP2_MCSPI_CHCTRL_EN BIT(0)
87#define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
88
89#define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
90
91/* We have 2 DMA channels per CS, one for RX and one for TX */
92struct omap2_mcspi_dma {
93 struct dma_chan *dma_tx;
94 struct dma_chan *dma_rx;
95
96 struct completion dma_tx_completion;
97 struct completion dma_rx_completion;
98
99 char dma_rx_ch_name[14];
100 char dma_tx_ch_name[14];
101};
102
103/* use PIO for small transfers, avoiding DMA setup/teardown overhead and
104 * cache operations; better heuristics consider wordsize and bitrate.
105 */
106#define DMA_MIN_BYTES 160
107
108
109/*
110 * Used for context save and restore, structure members to be updated whenever
111 * corresponding registers are modified.
112 */
113struct omap2_mcspi_regs {
114 u32 modulctrl;
115 u32 wakeupenable;
116 struct list_head cs;
117};
118
119struct omap2_mcspi {
120 struct completion txdone;
121 struct spi_master *master;
122 /* Virtual base address of the controller */
123 void __iomem *base;
124 unsigned long phys;
125 /* SPI1 has 4 channels, while SPI2 has 2 */
126 struct omap2_mcspi_dma *dma_channels;
127 struct device *dev;
128 struct omap2_mcspi_regs ctx;
129 int fifo_depth;
130 bool slave_aborted;
131 unsigned int pin_dir:1;
132 size_t max_xfer_len;
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 struct dma_async_tx_descriptor *tx;
401
402 mcspi = spi_master_get_devdata(spi->master);
403 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
404
405 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
406
407 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
408 xfer->tx_sg.nents,
409 DMA_MEM_TO_DEV,
410 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
411 if (tx) {
412 tx->callback = omap2_mcspi_tx_callback;
413 tx->callback_param = spi;
414 dmaengine_submit(tx);
415 } else {
416 /* FIXME: fall back to PIO? */
417 }
418 dma_async_issue_pending(mcspi_dma->dma_tx);
419 omap2_mcspi_set_dma_req(spi, 0, 1);
420}
421
422static unsigned
423omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
424 struct dma_slave_config cfg,
425 unsigned es)
426{
427 struct omap2_mcspi *mcspi;
428 struct omap2_mcspi_dma *mcspi_dma;
429 unsigned int count, transfer_reduction = 0;
430 struct scatterlist *sg_out[2];
431 int nb_sizes = 0, out_mapped_nents[2], ret, x;
432 size_t sizes[2];
433 u32 l;
434 int elements = 0;
435 int word_len, element_count;
436 struct omap2_mcspi_cs *cs = spi->controller_state;
437 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
438 struct dma_async_tx_descriptor *tx;
439
440 mcspi = spi_master_get_devdata(spi->master);
441 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
442 count = xfer->len;
443
444 /*
445 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
446 * it mentions reducing DMA transfer length by one element in master
447 * normal mode.
448 */
449 if (mcspi->fifo_depth == 0)
450 transfer_reduction = es;
451
452 word_len = cs->word_len;
453 l = mcspi_cached_chconf0(spi);
454
455 if (word_len <= 8)
456 element_count = count;
457 else if (word_len <= 16)
458 element_count = count >> 1;
459 else /* word_len <= 32 */
460 element_count = count >> 2;
461
462
463 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
464
465 /*
466 * Reduce DMA transfer length by one more if McSPI is
467 * configured in turbo mode.
468 */
469 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
470 transfer_reduction += es;
471
472 if (transfer_reduction) {
473 /* Split sgl into two. The second sgl won't be used. */
474 sizes[0] = count - transfer_reduction;
475 sizes[1] = transfer_reduction;
476 nb_sizes = 2;
477 } else {
478 /*
479 * Don't bother splitting the sgl. This essentially
480 * clones the original sgl.
481 */
482 sizes[0] = count;
483 nb_sizes = 1;
484 }
485
486 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
487 sizes, sg_out, out_mapped_nents, GFP_KERNEL);
488
489 if (ret < 0) {
490 dev_err(&spi->dev, "sg_split failed\n");
491 return 0;
492 }
493
494 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
495 out_mapped_nents[0], DMA_DEV_TO_MEM,
496 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
497 if (tx) {
498 tx->callback = omap2_mcspi_rx_callback;
499 tx->callback_param = spi;
500 dmaengine_submit(tx);
501 } else {
502 /* FIXME: fall back to PIO? */
503 }
504
505 dma_async_issue_pending(mcspi_dma->dma_rx);
506 omap2_mcspi_set_dma_req(spi, 1, 1);
507
508 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
509 if (ret || mcspi->slave_aborted) {
510 dmaengine_terminate_sync(mcspi_dma->dma_rx);
511 omap2_mcspi_set_dma_req(spi, 1, 0);
512 return 0;
513 }
514
515 for (x = 0; x < nb_sizes; x++)
516 kfree(sg_out[x]);
517
518 if (mcspi->fifo_depth > 0)
519 return count;
520
521 /*
522 * Due to the DMA transfer length reduction the missing bytes must
523 * be read manually to receive all of the expected data.
524 */
525 omap2_mcspi_set_enable(spi, 0);
526
527 elements = element_count - 1;
528
529 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
530 elements--;
531
532 if (!mcspi_wait_for_reg_bit(chstat_reg,
533 OMAP2_MCSPI_CHSTAT_RXS)) {
534 u32 w;
535
536 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
537 if (word_len <= 8)
538 ((u8 *)xfer->rx_buf)[elements++] = w;
539 else if (word_len <= 16)
540 ((u16 *)xfer->rx_buf)[elements++] = w;
541 else /* word_len <= 32 */
542 ((u32 *)xfer->rx_buf)[elements++] = w;
543 } else {
544 int bytes_per_word = mcspi_bytes_per_word(word_len);
545 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
546 count -= (bytes_per_word << 1);
547 omap2_mcspi_set_enable(spi, 1);
548 return count;
549 }
550 }
551 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
552 u32 w;
553
554 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
555 if (word_len <= 8)
556 ((u8 *)xfer->rx_buf)[elements] = w;
557 else if (word_len <= 16)
558 ((u16 *)xfer->rx_buf)[elements] = w;
559 else /* word_len <= 32 */
560 ((u32 *)xfer->rx_buf)[elements] = w;
561 } else {
562 dev_err(&spi->dev, "DMA RX last word empty\n");
563 count -= mcspi_bytes_per_word(word_len);
564 }
565 omap2_mcspi_set_enable(spi, 1);
566 return count;
567}
568
569static unsigned
570omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
571{
572 struct omap2_mcspi *mcspi;
573 struct omap2_mcspi_cs *cs = spi->controller_state;
574 struct omap2_mcspi_dma *mcspi_dma;
575 unsigned int count;
576 u8 *rx;
577 const u8 *tx;
578 struct dma_slave_config cfg;
579 enum dma_slave_buswidth width;
580 unsigned es;
581 void __iomem *chstat_reg;
582 void __iomem *irqstat_reg;
583 int wait_res;
584
585 mcspi = spi_master_get_devdata(spi->master);
586 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
587
588 if (cs->word_len <= 8) {
589 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
590 es = 1;
591 } else if (cs->word_len <= 16) {
592 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
593 es = 2;
594 } else {
595 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
596 es = 4;
597 }
598
599 count = xfer->len;
600
601 memset(&cfg, 0, sizeof(cfg));
602 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
603 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
604 cfg.src_addr_width = width;
605 cfg.dst_addr_width = width;
606 cfg.src_maxburst = 1;
607 cfg.dst_maxburst = 1;
608
609 rx = xfer->rx_buf;
610 tx = xfer->tx_buf;
611
612 mcspi->slave_aborted = false;
613 reinit_completion(&mcspi_dma->dma_tx_completion);
614 reinit_completion(&mcspi_dma->dma_rx_completion);
615 reinit_completion(&mcspi->txdone);
616 if (tx) {
617 /* Enable EOW IRQ to know end of tx in slave mode */
618 if (spi_controller_is_slave(spi->master))
619 mcspi_write_reg(spi->master,
620 OMAP2_MCSPI_IRQENABLE,
621 OMAP2_MCSPI_IRQSTATUS_EOW);
622 omap2_mcspi_tx_dma(spi, xfer, cfg);
623 }
624
625 if (rx != NULL)
626 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
627
628 if (tx != NULL) {
629 int ret;
630
631 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
632 if (ret || mcspi->slave_aborted) {
633 dmaengine_terminate_sync(mcspi_dma->dma_tx);
634 omap2_mcspi_set_dma_req(spi, 0, 0);
635 return 0;
636 }
637
638 if (spi_controller_is_slave(mcspi->master)) {
639 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
640 if (ret || mcspi->slave_aborted)
641 return 0;
642 }
643
644 if (mcspi->fifo_depth > 0) {
645 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
646
647 if (mcspi_wait_for_reg_bit(irqstat_reg,
648 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
649 dev_err(&spi->dev, "EOW timed out\n");
650
651 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
652 OMAP2_MCSPI_IRQSTATUS_EOW);
653 }
654
655 /* for TX_ONLY mode, be sure all words have shifted out */
656 if (rx == NULL) {
657 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
658 if (mcspi->fifo_depth > 0) {
659 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
660 OMAP2_MCSPI_CHSTAT_TXFFE);
661 if (wait_res < 0)
662 dev_err(&spi->dev, "TXFFE timed out\n");
663 } else {
664 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
665 OMAP2_MCSPI_CHSTAT_TXS);
666 if (wait_res < 0)
667 dev_err(&spi->dev, "TXS timed out\n");
668 }
669 if (wait_res >= 0 &&
670 (mcspi_wait_for_reg_bit(chstat_reg,
671 OMAP2_MCSPI_CHSTAT_EOT) < 0))
672 dev_err(&spi->dev, "EOT timed out\n");
673 }
674 }
675 return count;
676}
677
678static unsigned
679omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
680{
681 struct omap2_mcspi_cs *cs = spi->controller_state;
682 unsigned int count, c;
683 u32 l;
684 void __iomem *base = cs->base;
685 void __iomem *tx_reg;
686 void __iomem *rx_reg;
687 void __iomem *chstat_reg;
688 int word_len;
689
690 count = xfer->len;
691 c = count;
692 word_len = cs->word_len;
693
694 l = mcspi_cached_chconf0(spi);
695
696 /* We store the pre-calculated register addresses on stack to speed
697 * up the transfer loop. */
698 tx_reg = base + OMAP2_MCSPI_TX0;
699 rx_reg = base + OMAP2_MCSPI_RX0;
700 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
701
702 if (c < (word_len>>3))
703 return 0;
704
705 if (word_len <= 8) {
706 u8 *rx;
707 const u8 *tx;
708
709 rx = xfer->rx_buf;
710 tx = xfer->tx_buf;
711
712 do {
713 c -= 1;
714 if (tx != NULL) {
715 if (mcspi_wait_for_reg_bit(chstat_reg,
716 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
717 dev_err(&spi->dev, "TXS timed out\n");
718 goto out;
719 }
720 dev_vdbg(&spi->dev, "write-%d %02x\n",
721 word_len, *tx);
722 writel_relaxed(*tx++, tx_reg);
723 }
724 if (rx != NULL) {
725 if (mcspi_wait_for_reg_bit(chstat_reg,
726 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
727 dev_err(&spi->dev, "RXS timed out\n");
728 goto out;
729 }
730
731 if (c == 1 && tx == NULL &&
732 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
733 omap2_mcspi_set_enable(spi, 0);
734 *rx++ = readl_relaxed(rx_reg);
735 dev_vdbg(&spi->dev, "read-%d %02x\n",
736 word_len, *(rx - 1));
737 if (mcspi_wait_for_reg_bit(chstat_reg,
738 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
739 dev_err(&spi->dev,
740 "RXS timed out\n");
741 goto out;
742 }
743 c = 0;
744 } else if (c == 0 && tx == NULL) {
745 omap2_mcspi_set_enable(spi, 0);
746 }
747
748 *rx++ = readl_relaxed(rx_reg);
749 dev_vdbg(&spi->dev, "read-%d %02x\n",
750 word_len, *(rx - 1));
751 }
752 } while (c);
753 } else if (word_len <= 16) {
754 u16 *rx;
755 const u16 *tx;
756
757 rx = xfer->rx_buf;
758 tx = xfer->tx_buf;
759 do {
760 c -= 2;
761 if (tx != NULL) {
762 if (mcspi_wait_for_reg_bit(chstat_reg,
763 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
764 dev_err(&spi->dev, "TXS timed out\n");
765 goto out;
766 }
767 dev_vdbg(&spi->dev, "write-%d %04x\n",
768 word_len, *tx);
769 writel_relaxed(*tx++, tx_reg);
770 }
771 if (rx != NULL) {
772 if (mcspi_wait_for_reg_bit(chstat_reg,
773 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
774 dev_err(&spi->dev, "RXS timed out\n");
775 goto out;
776 }
777
778 if (c == 2 && tx == NULL &&
779 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
780 omap2_mcspi_set_enable(spi, 0);
781 *rx++ = readl_relaxed(rx_reg);
782 dev_vdbg(&spi->dev, "read-%d %04x\n",
783 word_len, *(rx - 1));
784 if (mcspi_wait_for_reg_bit(chstat_reg,
785 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
786 dev_err(&spi->dev,
787 "RXS timed out\n");
788 goto out;
789 }
790 c = 0;
791 } else if (c == 0 && tx == NULL) {
792 omap2_mcspi_set_enable(spi, 0);
793 }
794
795 *rx++ = readl_relaxed(rx_reg);
796 dev_vdbg(&spi->dev, "read-%d %04x\n",
797 word_len, *(rx - 1));
798 }
799 } while (c >= 2);
800 } else if (word_len <= 32) {
801 u32 *rx;
802 const u32 *tx;
803
804 rx = xfer->rx_buf;
805 tx = xfer->tx_buf;
806 do {
807 c -= 4;
808 if (tx != NULL) {
809 if (mcspi_wait_for_reg_bit(chstat_reg,
810 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
811 dev_err(&spi->dev, "TXS timed out\n");
812 goto out;
813 }
814 dev_vdbg(&spi->dev, "write-%d %08x\n",
815 word_len, *tx);
816 writel_relaxed(*tx++, tx_reg);
817 }
818 if (rx != NULL) {
819 if (mcspi_wait_for_reg_bit(chstat_reg,
820 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
821 dev_err(&spi->dev, "RXS timed out\n");
822 goto out;
823 }
824
825 if (c == 4 && tx == NULL &&
826 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
827 omap2_mcspi_set_enable(spi, 0);
828 *rx++ = readl_relaxed(rx_reg);
829 dev_vdbg(&spi->dev, "read-%d %08x\n",
830 word_len, *(rx - 1));
831 if (mcspi_wait_for_reg_bit(chstat_reg,
832 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
833 dev_err(&spi->dev,
834 "RXS timed out\n");
835 goto out;
836 }
837 c = 0;
838 } else if (c == 0 && tx == NULL) {
839 omap2_mcspi_set_enable(spi, 0);
840 }
841
842 *rx++ = readl_relaxed(rx_reg);
843 dev_vdbg(&spi->dev, "read-%d %08x\n",
844 word_len, *(rx - 1));
845 }
846 } while (c >= 4);
847 }
848
849 /* for TX_ONLY mode, be sure all words have shifted out */
850 if (xfer->rx_buf == NULL) {
851 if (mcspi_wait_for_reg_bit(chstat_reg,
852 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
853 dev_err(&spi->dev, "TXS timed out\n");
854 } else if (mcspi_wait_for_reg_bit(chstat_reg,
855 OMAP2_MCSPI_CHSTAT_EOT) < 0)
856 dev_err(&spi->dev, "EOT timed out\n");
857
858 /* disable chan to purge rx datas received in TX_ONLY transfer,
859 * otherwise these rx datas will affect the direct following
860 * RX_ONLY transfer.
861 */
862 omap2_mcspi_set_enable(spi, 0);
863 }
864out:
865 omap2_mcspi_set_enable(spi, 1);
866 return count - c;
867}
868
869static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
870{
871 u32 div;
872
873 for (div = 0; div < 15; div++)
874 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
875 return div;
876
877 return 15;
878}
879
880/* called only when no transfer is active to this device */
881static int omap2_mcspi_setup_transfer(struct spi_device *spi,
882 struct spi_transfer *t)
883{
884 struct omap2_mcspi_cs *cs = spi->controller_state;
885 struct omap2_mcspi *mcspi;
886 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
887 u8 word_len = spi->bits_per_word;
888 u32 speed_hz = spi->max_speed_hz;
889
890 mcspi = spi_master_get_devdata(spi->master);
891
892 if (t != NULL && t->bits_per_word)
893 word_len = t->bits_per_word;
894
895 cs->word_len = word_len;
896
897 if (t && t->speed_hz)
898 speed_hz = t->speed_hz;
899
900 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
901 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
902 clkd = omap2_mcspi_calc_divisor(speed_hz);
903 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
904 clkg = 0;
905 } else {
906 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
907 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
908 clkd = (div - 1) & 0xf;
909 extclk = (div - 1) >> 4;
910 clkg = OMAP2_MCSPI_CHCONF_CLKG;
911 }
912
913 l = mcspi_cached_chconf0(spi);
914
915 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
916 * REVISIT: this controller could support SPI_3WIRE mode.
917 */
918 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
919 l &= ~OMAP2_MCSPI_CHCONF_IS;
920 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
921 l |= OMAP2_MCSPI_CHCONF_DPE0;
922 } else {
923 l |= OMAP2_MCSPI_CHCONF_IS;
924 l |= OMAP2_MCSPI_CHCONF_DPE1;
925 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
926 }
927
928 /* wordlength */
929 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
930 l |= (word_len - 1) << 7;
931
932 /* set chipselect polarity; manage with FORCE */
933 if (!(spi->mode & SPI_CS_HIGH))
934 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
935 else
936 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
937
938 /* set clock divisor */
939 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
940 l |= clkd << 2;
941
942 /* set clock granularity */
943 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
944 l |= clkg;
945 if (clkg) {
946 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
947 cs->chctrl0 |= extclk << 8;
948 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
949 }
950
951 /* set SPI mode 0..3 */
952 if (spi->mode & SPI_CPOL)
953 l |= OMAP2_MCSPI_CHCONF_POL;
954 else
955 l &= ~OMAP2_MCSPI_CHCONF_POL;
956 if (spi->mode & SPI_CPHA)
957 l |= OMAP2_MCSPI_CHCONF_PHA;
958 else
959 l &= ~OMAP2_MCSPI_CHCONF_PHA;
960
961 mcspi_write_chconf0(spi, l);
962
963 cs->mode = spi->mode;
964
965 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
966 speed_hz,
967 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
968 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
969
970 return 0;
971}
972
973/*
974 * Note that we currently allow DMA only if we get a channel
975 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
976 */
977static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
978 struct omap2_mcspi_dma *mcspi_dma)
979{
980 int ret = 0;
981
982 mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
983 mcspi_dma->dma_rx_ch_name);
984 if (IS_ERR(mcspi_dma->dma_rx)) {
985 ret = PTR_ERR(mcspi_dma->dma_rx);
986 mcspi_dma->dma_rx = NULL;
987 goto no_dma;
988 }
989
990 mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
991 mcspi_dma->dma_tx_ch_name);
992 if (IS_ERR(mcspi_dma->dma_tx)) {
993 ret = PTR_ERR(mcspi_dma->dma_tx);
994 mcspi_dma->dma_tx = NULL;
995 dma_release_channel(mcspi_dma->dma_rx);
996 mcspi_dma->dma_rx = NULL;
997 }
998
999 init_completion(&mcspi_dma->dma_rx_completion);
1000 init_completion(&mcspi_dma->dma_tx_completion);
1001
1002no_dma:
1003 return ret;
1004}
1005
1006static void omap2_mcspi_release_dma(struct spi_master *master)
1007{
1008 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1009 struct omap2_mcspi_dma *mcspi_dma;
1010 int i;
1011
1012 for (i = 0; i < master->num_chipselect; i++) {
1013 mcspi_dma = &mcspi->dma_channels[i];
1014
1015 if (mcspi_dma->dma_rx) {
1016 dma_release_channel(mcspi_dma->dma_rx);
1017 mcspi_dma->dma_rx = NULL;
1018 }
1019 if (mcspi_dma->dma_tx) {
1020 dma_release_channel(mcspi_dma->dma_tx);
1021 mcspi_dma->dma_tx = NULL;
1022 }
1023 }
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_cs *cs = spi->controller_state;
1032
1033 if (!cs) {
1034 cs = kzalloc(sizeof *cs, GFP_KERNEL);
1035 if (!cs)
1036 return -ENOMEM;
1037 cs->base = mcspi->base + spi->chip_select * 0x14;
1038 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1039 cs->mode = 0;
1040 cs->chconf0 = 0;
1041 cs->chctrl0 = 0;
1042 spi->controller_state = cs;
1043 /* Link this to context save list */
1044 list_add_tail(&cs->node, &ctx->cs);
1045 }
1046
1047 ret = pm_runtime_get_sync(mcspi->dev);
1048 if (ret < 0) {
1049 pm_runtime_put_noidle(mcspi->dev);
1050
1051 return ret;
1052 }
1053
1054 ret = omap2_mcspi_setup_transfer(spi, NULL);
1055 pm_runtime_mark_last_busy(mcspi->dev);
1056 pm_runtime_put_autosuspend(mcspi->dev);
1057
1058 return ret;
1059}
1060
1061static void omap2_mcspi_cleanup(struct spi_device *spi)
1062{
1063 struct omap2_mcspi_cs *cs;
1064
1065 if (spi->controller_state) {
1066 /* Unlink controller state from context save list */
1067 cs = spi->controller_state;
1068 list_del(&cs->node);
1069
1070 kfree(cs);
1071 }
1072}
1073
1074static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1075{
1076 struct omap2_mcspi *mcspi = data;
1077 u32 irqstat;
1078
1079 irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1080 if (!irqstat)
1081 return IRQ_NONE;
1082
1083 /* Disable IRQ and wakeup slave xfer task */
1084 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1085 if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1086 complete(&mcspi->txdone);
1087
1088 return IRQ_HANDLED;
1089}
1090
1091static int omap2_mcspi_slave_abort(struct spi_master *master)
1092{
1093 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1094 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1095
1096 mcspi->slave_aborted = true;
1097 complete(&mcspi_dma->dma_rx_completion);
1098 complete(&mcspi_dma->dma_tx_completion);
1099 complete(&mcspi->txdone);
1100
1101 return 0;
1102}
1103
1104static int omap2_mcspi_transfer_one(struct spi_master *master,
1105 struct spi_device *spi,
1106 struct spi_transfer *t)
1107{
1108
1109 /* We only enable one channel at a time -- the one whose message is
1110 * -- although this controller would gladly
1111 * arbitrate among multiple channels. This corresponds to "single
1112 * channel" master mode. As a side effect, we need to manage the
1113 * chipselect with the FORCE bit ... CS != channel enable.
1114 */
1115
1116 struct omap2_mcspi *mcspi;
1117 struct omap2_mcspi_dma *mcspi_dma;
1118 struct omap2_mcspi_cs *cs;
1119 struct omap2_mcspi_device_config *cd;
1120 int par_override = 0;
1121 int status = 0;
1122 u32 chconf;
1123
1124 mcspi = spi_master_get_devdata(master);
1125 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1126 cs = spi->controller_state;
1127 cd = spi->controller_data;
1128
1129 /*
1130 * The slave driver could have changed spi->mode in which case
1131 * it will be different from cs->mode (the current hardware setup).
1132 * If so, set par_override (even though its not a parity issue) so
1133 * omap2_mcspi_setup_transfer will be called to configure the hardware
1134 * with the correct mode on the first iteration of the loop below.
1135 */
1136 if (spi->mode != cs->mode)
1137 par_override = 1;
1138
1139 omap2_mcspi_set_enable(spi, 0);
1140
1141 if (spi->cs_gpiod)
1142 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1143
1144 if (par_override ||
1145 (t->speed_hz != spi->max_speed_hz) ||
1146 (t->bits_per_word != spi->bits_per_word)) {
1147 par_override = 1;
1148 status = omap2_mcspi_setup_transfer(spi, t);
1149 if (status < 0)
1150 goto out;
1151 if (t->speed_hz == spi->max_speed_hz &&
1152 t->bits_per_word == spi->bits_per_word)
1153 par_override = 0;
1154 }
1155 if (cd && cd->cs_per_word) {
1156 chconf = mcspi->ctx.modulctrl;
1157 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1158 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1159 mcspi->ctx.modulctrl =
1160 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1161 }
1162
1163 chconf = mcspi_cached_chconf0(spi);
1164 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1165 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1166
1167 if (t->tx_buf == NULL)
1168 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1169 else if (t->rx_buf == NULL)
1170 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1171
1172 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1173 /* Turbo mode is for more than one word */
1174 if (t->len > ((cs->word_len + 7) >> 3))
1175 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1176 }
1177
1178 mcspi_write_chconf0(spi, chconf);
1179
1180 if (t->len) {
1181 unsigned count;
1182
1183 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1184 master->cur_msg_mapped &&
1185 master->can_dma(master, spi, t))
1186 omap2_mcspi_set_fifo(spi, t, 1);
1187
1188 omap2_mcspi_set_enable(spi, 1);
1189
1190 /* RX_ONLY mode needs dummy data in TX reg */
1191 if (t->tx_buf == NULL)
1192 writel_relaxed(0, cs->base
1193 + OMAP2_MCSPI_TX0);
1194
1195 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1196 master->cur_msg_mapped &&
1197 master->can_dma(master, spi, t))
1198 count = omap2_mcspi_txrx_dma(spi, t);
1199 else
1200 count = omap2_mcspi_txrx_pio(spi, t);
1201
1202 if (count != t->len) {
1203 status = -EIO;
1204 goto out;
1205 }
1206 }
1207
1208 omap2_mcspi_set_enable(spi, 0);
1209
1210 if (mcspi->fifo_depth > 0)
1211 omap2_mcspi_set_fifo(spi, t, 0);
1212
1213out:
1214 /* Restore defaults if they were overriden */
1215 if (par_override) {
1216 par_override = 0;
1217 status = omap2_mcspi_setup_transfer(spi, NULL);
1218 }
1219
1220 if (cd && cd->cs_per_word) {
1221 chconf = mcspi->ctx.modulctrl;
1222 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1223 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1224 mcspi->ctx.modulctrl =
1225 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1226 }
1227
1228 omap2_mcspi_set_enable(spi, 0);
1229
1230 if (spi->cs_gpiod)
1231 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1232
1233 if (mcspi->fifo_depth > 0 && t)
1234 omap2_mcspi_set_fifo(spi, t, 0);
1235
1236 return status;
1237}
1238
1239static int omap2_mcspi_prepare_message(struct spi_master *master,
1240 struct spi_message *msg)
1241{
1242 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1243 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1244 struct omap2_mcspi_cs *cs;
1245
1246 /* Only a single channel can have the FORCE bit enabled
1247 * in its chconf0 register.
1248 * Scan all channels and disable them except the current one.
1249 * A FORCE can remain from a last transfer having cs_change enabled
1250 */
1251 list_for_each_entry(cs, &ctx->cs, node) {
1252 if (msg->spi->controller_state == cs)
1253 continue;
1254
1255 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1256 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1257 writel_relaxed(cs->chconf0,
1258 cs->base + OMAP2_MCSPI_CHCONF0);
1259 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1260 }
1261 }
1262
1263 return 0;
1264}
1265
1266static bool omap2_mcspi_can_dma(struct spi_master *master,
1267 struct spi_device *spi,
1268 struct spi_transfer *xfer)
1269{
1270 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1271 struct omap2_mcspi_dma *mcspi_dma =
1272 &mcspi->dma_channels[spi->chip_select];
1273
1274 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1275 return false;
1276
1277 if (spi_controller_is_slave(master))
1278 return true;
1279
1280 master->dma_rx = mcspi_dma->dma_rx;
1281 master->dma_tx = mcspi_dma->dma_tx;
1282
1283 return (xfer->len >= DMA_MIN_BYTES);
1284}
1285
1286static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1287{
1288 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1289 struct omap2_mcspi_dma *mcspi_dma =
1290 &mcspi->dma_channels[spi->chip_select];
1291
1292 if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1293 return mcspi->max_xfer_len;
1294
1295 return SIZE_MAX;
1296}
1297
1298static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1299{
1300 struct spi_master *master = mcspi->master;
1301 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1302 int ret = 0;
1303
1304 ret = pm_runtime_get_sync(mcspi->dev);
1305 if (ret < 0) {
1306 pm_runtime_put_noidle(mcspi->dev);
1307
1308 return ret;
1309 }
1310
1311 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1312 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1313 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1314
1315 omap2_mcspi_set_mode(master);
1316 pm_runtime_mark_last_busy(mcspi->dev);
1317 pm_runtime_put_autosuspend(mcspi->dev);
1318 return 0;
1319}
1320
1321/*
1322 * When SPI wake up from off-mode, CS is in activate state. If it was in
1323 * inactive state when driver was suspend, then force it to inactive state at
1324 * wake up.
1325 */
1326static int omap_mcspi_runtime_resume(struct device *dev)
1327{
1328 struct spi_master *master = dev_get_drvdata(dev);
1329 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1330 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1331 struct omap2_mcspi_cs *cs;
1332
1333 /* McSPI: context restore */
1334 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1335 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1336
1337 list_for_each_entry(cs, &ctx->cs, node) {
1338 /*
1339 * We need to toggle CS state for OMAP take this
1340 * change in account.
1341 */
1342 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1343 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1344 writel_relaxed(cs->chconf0,
1345 cs->base + OMAP2_MCSPI_CHCONF0);
1346 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1347 writel_relaxed(cs->chconf0,
1348 cs->base + OMAP2_MCSPI_CHCONF0);
1349 } else {
1350 writel_relaxed(cs->chconf0,
1351 cs->base + OMAP2_MCSPI_CHCONF0);
1352 }
1353 }
1354
1355 return 0;
1356}
1357
1358static struct omap2_mcspi_platform_config omap2_pdata = {
1359 .regs_offset = 0,
1360};
1361
1362static struct omap2_mcspi_platform_config omap4_pdata = {
1363 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1364};
1365
1366static struct omap2_mcspi_platform_config am654_pdata = {
1367 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1368 .max_xfer_len = SZ_4K - 1,
1369};
1370
1371static const struct of_device_id omap_mcspi_of_match[] = {
1372 {
1373 .compatible = "ti,omap2-mcspi",
1374 .data = &omap2_pdata,
1375 },
1376 {
1377 .compatible = "ti,omap4-mcspi",
1378 .data = &omap4_pdata,
1379 },
1380 {
1381 .compatible = "ti,am654-mcspi",
1382 .data = &am654_pdata,
1383 },
1384 { },
1385};
1386MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1387
1388static int omap2_mcspi_probe(struct platform_device *pdev)
1389{
1390 struct spi_master *master;
1391 const struct omap2_mcspi_platform_config *pdata;
1392 struct omap2_mcspi *mcspi;
1393 struct resource *r;
1394 int status = 0, i;
1395 u32 regs_offset = 0;
1396 struct device_node *node = pdev->dev.of_node;
1397 const struct of_device_id *match;
1398
1399 if (of_property_read_bool(node, "spi-slave"))
1400 master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1401 else
1402 master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1403 if (!master)
1404 return -ENOMEM;
1405
1406 /* the spi->mode bits understood by this driver: */
1407 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1408 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1409 master->setup = omap2_mcspi_setup;
1410 master->auto_runtime_pm = true;
1411 master->prepare_message = omap2_mcspi_prepare_message;
1412 master->can_dma = omap2_mcspi_can_dma;
1413 master->transfer_one = omap2_mcspi_transfer_one;
1414 master->set_cs = omap2_mcspi_set_cs;
1415 master->cleanup = omap2_mcspi_cleanup;
1416 master->slave_abort = omap2_mcspi_slave_abort;
1417 master->dev.of_node = node;
1418 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1419 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1420 master->use_gpio_descriptors = true;
1421
1422 platform_set_drvdata(pdev, master);
1423
1424 mcspi = spi_master_get_devdata(master);
1425 mcspi->master = master;
1426
1427 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1428 if (match) {
1429 u32 num_cs = 1; /* default number of chipselect */
1430 pdata = match->data;
1431
1432 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1433 master->num_chipselect = num_cs;
1434 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1435 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1436 } else {
1437 pdata = dev_get_platdata(&pdev->dev);
1438 master->num_chipselect = pdata->num_cs;
1439 mcspi->pin_dir = pdata->pin_dir;
1440 }
1441 regs_offset = pdata->regs_offset;
1442 if (pdata->max_xfer_len) {
1443 mcspi->max_xfer_len = pdata->max_xfer_len;
1444 master->max_transfer_size = omap2_mcspi_max_xfer_size;
1445 }
1446
1447 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1448 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1449 if (IS_ERR(mcspi->base)) {
1450 status = PTR_ERR(mcspi->base);
1451 goto free_master;
1452 }
1453 mcspi->phys = r->start + regs_offset;
1454 mcspi->base += regs_offset;
1455
1456 mcspi->dev = &pdev->dev;
1457
1458 INIT_LIST_HEAD(&mcspi->ctx.cs);
1459
1460 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1461 sizeof(struct omap2_mcspi_dma),
1462 GFP_KERNEL);
1463 if (mcspi->dma_channels == NULL) {
1464 status = -ENOMEM;
1465 goto free_master;
1466 }
1467
1468 for (i = 0; i < master->num_chipselect; i++) {
1469 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1470 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1471
1472 status = omap2_mcspi_request_dma(mcspi,
1473 &mcspi->dma_channels[i]);
1474 if (status == -EPROBE_DEFER)
1475 goto free_master;
1476 }
1477
1478 status = platform_get_irq(pdev, 0);
1479 if (status == -EPROBE_DEFER)
1480 goto free_master;
1481 if (status < 0) {
1482 dev_err(&pdev->dev, "no irq resource found\n");
1483 goto free_master;
1484 }
1485 init_completion(&mcspi->txdone);
1486 status = devm_request_irq(&pdev->dev, status,
1487 omap2_mcspi_irq_handler, 0, pdev->name,
1488 mcspi);
1489 if (status) {
1490 dev_err(&pdev->dev, "Cannot request IRQ");
1491 goto free_master;
1492 }
1493
1494 pm_runtime_use_autosuspend(&pdev->dev);
1495 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1496 pm_runtime_enable(&pdev->dev);
1497
1498 status = omap2_mcspi_controller_setup(mcspi);
1499 if (status < 0)
1500 goto disable_pm;
1501
1502 status = devm_spi_register_controller(&pdev->dev, master);
1503 if (status < 0)
1504 goto disable_pm;
1505
1506 return status;
1507
1508disable_pm:
1509 pm_runtime_dont_use_autosuspend(&pdev->dev);
1510 pm_runtime_put_sync(&pdev->dev);
1511 pm_runtime_disable(&pdev->dev);
1512free_master:
1513 omap2_mcspi_release_dma(master);
1514 spi_master_put(master);
1515 return status;
1516}
1517
1518static int omap2_mcspi_remove(struct platform_device *pdev)
1519{
1520 struct spi_master *master = platform_get_drvdata(pdev);
1521 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1522
1523 omap2_mcspi_release_dma(master);
1524
1525 pm_runtime_dont_use_autosuspend(mcspi->dev);
1526 pm_runtime_put_sync(mcspi->dev);
1527 pm_runtime_disable(&pdev->dev);
1528
1529 return 0;
1530}
1531
1532/* work with hotplug and coldplug */
1533MODULE_ALIAS("platform:omap2_mcspi");
1534
1535static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1536{
1537 struct spi_master *master = dev_get_drvdata(dev);
1538 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1539 int error;
1540
1541 error = pinctrl_pm_select_sleep_state(dev);
1542 if (error)
1543 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1544 __func__, error);
1545
1546 error = spi_master_suspend(master);
1547 if (error)
1548 dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1549 __func__, error);
1550
1551 return pm_runtime_force_suspend(dev);
1552}
1553
1554static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1555{
1556 struct spi_master *master = dev_get_drvdata(dev);
1557 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1558 int error;
1559
1560 error = pinctrl_pm_select_default_state(dev);
1561 if (error)
1562 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1563 __func__, error);
1564
1565 error = spi_master_resume(master);
1566 if (error)
1567 dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1568 __func__, error);
1569
1570 return pm_runtime_force_resume(dev);
1571}
1572
1573static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1574 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1575 omap2_mcspi_resume)
1576 .runtime_resume = omap_mcspi_runtime_resume,
1577};
1578
1579static struct platform_driver omap2_mcspi_driver = {
1580 .driver = {
1581 .name = "omap2_mcspi",
1582 .pm = &omap2_mcspi_pm_ops,
1583 .of_match_table = omap_mcspi_of_match,
1584 },
1585 .probe = omap2_mcspi_probe,
1586 .remove = omap2_mcspi_remove,
1587};
1588
1589module_platform_driver(omap2_mcspi_driver);
1590MODULE_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");