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 Yrjola <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
28 #include <linux/spi/spi.h>
29
30 #include <linux/platform_data/spi-omap2-mcspi.h>
31
32 #define OMAP2_MCSPI_MAX_FREQ 48000000
33 #define OMAP2_MCSPI_MAX_DIVIDER 4096
34 #define OMAP2_MCSPI_MAX_FIFODEPTH 64
35 #define OMAP2_MCSPI_MAX_FIFOWCNT 0xFFFF
36 #define SPI_AUTOSUSPEND_TIMEOUT 2000
37
38 #define OMAP2_MCSPI_REVISION 0x00
39 #define OMAP2_MCSPI_SYSSTATUS 0x14
40 #define OMAP2_MCSPI_IRQSTATUS 0x18
41 #define OMAP2_MCSPI_IRQENABLE 0x1c
42 #define OMAP2_MCSPI_WAKEUPENABLE 0x20
43 #define OMAP2_MCSPI_SYST 0x24
44 #define OMAP2_MCSPI_MODULCTRL 0x28
45 #define OMAP2_MCSPI_XFERLEVEL 0x7c
46
47 /* per-channel banks, 0x14 bytes each, first is: */
48 #define OMAP2_MCSPI_CHCONF0 0x2c
49 #define OMAP2_MCSPI_CHSTAT0 0x30
50 #define OMAP2_MCSPI_CHCTRL0 0x34
51 #define OMAP2_MCSPI_TX0 0x38
52 #define OMAP2_MCSPI_RX0 0x3c
53
54 /* per-register bitmasks: */
55 #define OMAP2_MCSPI_IRQSTATUS_EOW BIT(17)
56
57 #define OMAP2_MCSPI_MODULCTRL_SINGLE BIT(0)
58 #define OMAP2_MCSPI_MODULCTRL_MS BIT(2)
59 #define OMAP2_MCSPI_MODULCTRL_STEST BIT(3)
60
61 #define OMAP2_MCSPI_CHCONF_PHA BIT(0)
62 #define OMAP2_MCSPI_CHCONF_POL BIT(1)
63 #define OMAP2_MCSPI_CHCONF_CLKD_MASK (0x0f << 2)
64 #define OMAP2_MCSPI_CHCONF_EPOL BIT(6)
65 #define OMAP2_MCSPI_CHCONF_WL_MASK (0x1f << 7)
66 #define OMAP2_MCSPI_CHCONF_TRM_RX_ONLY BIT(12)
67 #define OMAP2_MCSPI_CHCONF_TRM_TX_ONLY BIT(13)
68 #define OMAP2_MCSPI_CHCONF_TRM_MASK (0x03 << 12)
69 #define OMAP2_MCSPI_CHCONF_DMAW BIT(14)
70 #define OMAP2_MCSPI_CHCONF_DMAR BIT(15)
71 #define OMAP2_MCSPI_CHCONF_DPE0 BIT(16)
72 #define OMAP2_MCSPI_CHCONF_DPE1 BIT(17)
73 #define OMAP2_MCSPI_CHCONF_IS BIT(18)
74 #define OMAP2_MCSPI_CHCONF_TURBO BIT(19)
75 #define OMAP2_MCSPI_CHCONF_FORCE BIT(20)
76 #define OMAP2_MCSPI_CHCONF_FFET BIT(27)
77 #define OMAP2_MCSPI_CHCONF_FFER BIT(28)
78 #define OMAP2_MCSPI_CHCONF_CLKG BIT(29)
79
80 #define OMAP2_MCSPI_CHSTAT_RXS BIT(0)
81 #define OMAP2_MCSPI_CHSTAT_TXS BIT(1)
82 #define OMAP2_MCSPI_CHSTAT_EOT BIT(2)
83 #define OMAP2_MCSPI_CHSTAT_TXFFE BIT(3)
84
85 #define OMAP2_MCSPI_CHCTRL_EN BIT(0)
86 #define OMAP2_MCSPI_CHCTRL_EXTCLK_MASK (0xff << 8)
87
88 #define OMAP2_MCSPI_WAKEUPENABLE_WKEN BIT(0)
89
90 /* We have 2 DMA channels per CS, one for RX and one for TX */
91 struct omap2_mcspi_dma {
92 struct dma_chan *dma_tx;
93 struct dma_chan *dma_rx;
94
95 struct completion dma_tx_completion;
96 struct completion dma_rx_completion;
97
98 char dma_rx_ch_name[14];
99 char dma_tx_ch_name[14];
100 };
101
102 /* use PIO for small transfers, avoiding DMA setup/teardown overhead and
103 * cache operations; better heuristics consider wordsize and bitrate.
104 */
105 #define DMA_MIN_BYTES 160
106
107
108 /*
109 * Used for context save and restore, structure members to be updated whenever
110 * corresponding registers are modified.
111 */
112 struct omap2_mcspi_regs {
113 u32 modulctrl;
114 u32 wakeupenable;
115 struct list_head cs;
116 };
117
118 struct omap2_mcspi {
119 struct completion txdone;
120 struct spi_master *master;
121 /* Virtual base address of the controller */
122 void __iomem *base;
123 unsigned long phys;
124 /* SPI1 has 4 channels, while SPI2 has 2 */
125 struct omap2_mcspi_dma *dma_channels;
126 struct device *dev;
127 struct omap2_mcspi_regs ctx;
128 int fifo_depth;
129 bool slave_aborted;
130 unsigned int pin_dir:1;
131 size_t max_xfer_len;
132 };
133
134 struct omap2_mcspi_cs {
135 void __iomem *base;
136 unsigned long phys;
137 int word_len;
138 u16 mode;
139 struct list_head node;
140 /* Context save and restore shadow register */
141 u32 chconf0, chctrl0;
142 };
143
mcspi_write_reg(struct spi_master * master,int idx,u32 val)144 static inline void mcspi_write_reg(struct spi_master *master,
145 int idx, u32 val)
146 {
147 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
148
149 writel_relaxed(val, mcspi->base + idx);
150 }
151
mcspi_read_reg(struct spi_master * master,int idx)152 static inline u32 mcspi_read_reg(struct spi_master *master, int idx)
153 {
154 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
155
156 return readl_relaxed(mcspi->base + idx);
157 }
158
mcspi_write_cs_reg(const struct spi_device * spi,int idx,u32 val)159 static inline void mcspi_write_cs_reg(const struct spi_device *spi,
160 int idx, u32 val)
161 {
162 struct omap2_mcspi_cs *cs = spi->controller_state;
163
164 writel_relaxed(val, cs->base + idx);
165 }
166
mcspi_read_cs_reg(const struct spi_device * spi,int idx)167 static inline u32 mcspi_read_cs_reg(const struct spi_device *spi, int idx)
168 {
169 struct omap2_mcspi_cs *cs = spi->controller_state;
170
171 return readl_relaxed(cs->base + idx);
172 }
173
mcspi_cached_chconf0(const struct spi_device * spi)174 static inline u32 mcspi_cached_chconf0(const struct spi_device *spi)
175 {
176 struct omap2_mcspi_cs *cs = spi->controller_state;
177
178 return cs->chconf0;
179 }
180
mcspi_write_chconf0(const struct spi_device * spi,u32 val)181 static inline void mcspi_write_chconf0(const struct spi_device *spi, u32 val)
182 {
183 struct omap2_mcspi_cs *cs = spi->controller_state;
184
185 cs->chconf0 = val;
186 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, val);
187 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCONF0);
188 }
189
mcspi_bytes_per_word(int word_len)190 static inline int mcspi_bytes_per_word(int word_len)
191 {
192 if (word_len <= 8)
193 return 1;
194 else if (word_len <= 16)
195 return 2;
196 else /* word_len <= 32 */
197 return 4;
198 }
199
omap2_mcspi_set_dma_req(const struct spi_device * spi,int is_read,int enable)200 static void omap2_mcspi_set_dma_req(const struct spi_device *spi,
201 int is_read, int enable)
202 {
203 u32 l, rw;
204
205 l = mcspi_cached_chconf0(spi);
206
207 if (is_read) /* 1 is read, 0 write */
208 rw = OMAP2_MCSPI_CHCONF_DMAR;
209 else
210 rw = OMAP2_MCSPI_CHCONF_DMAW;
211
212 if (enable)
213 l |= rw;
214 else
215 l &= ~rw;
216
217 mcspi_write_chconf0(spi, l);
218 }
219
omap2_mcspi_set_enable(const struct spi_device * spi,int enable)220 static void omap2_mcspi_set_enable(const struct spi_device *spi, int enable)
221 {
222 struct omap2_mcspi_cs *cs = spi->controller_state;
223 u32 l;
224
225 l = cs->chctrl0;
226 if (enable)
227 l |= OMAP2_MCSPI_CHCTRL_EN;
228 else
229 l &= ~OMAP2_MCSPI_CHCTRL_EN;
230 cs->chctrl0 = l;
231 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
232 /* Flash post-writes */
233 mcspi_read_cs_reg(spi, OMAP2_MCSPI_CHCTRL0);
234 }
235
omap2_mcspi_set_cs(struct spi_device * spi,bool enable)236 static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable)
237 {
238 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
239 u32 l;
240
241 /* The controller handles the inverted chip selects
242 * using the OMAP2_MCSPI_CHCONF_EPOL bit so revert
243 * the inversion from the core spi_set_cs function.
244 */
245 if (spi->mode & SPI_CS_HIGH)
246 enable = !enable;
247
248 if (spi->controller_state) {
249 int err = pm_runtime_get_sync(mcspi->dev);
250 if (err < 0) {
251 pm_runtime_put_noidle(mcspi->dev);
252 dev_err(mcspi->dev, "failed to get sync: %d\n", err);
253 return;
254 }
255
256 l = mcspi_cached_chconf0(spi);
257
258 if (enable)
259 l &= ~OMAP2_MCSPI_CHCONF_FORCE;
260 else
261 l |= OMAP2_MCSPI_CHCONF_FORCE;
262
263 mcspi_write_chconf0(spi, l);
264
265 pm_runtime_mark_last_busy(mcspi->dev);
266 pm_runtime_put_autosuspend(mcspi->dev);
267 }
268 }
269
omap2_mcspi_set_mode(struct spi_master * master)270 static void omap2_mcspi_set_mode(struct spi_master *master)
271 {
272 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
273 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
274 u32 l;
275
276 /*
277 * Choose master or slave mode
278 */
279 l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL);
280 l &= ~(OMAP2_MCSPI_MODULCTRL_STEST);
281 if (spi_controller_is_slave(master)) {
282 l |= (OMAP2_MCSPI_MODULCTRL_MS);
283 } else {
284 l &= ~(OMAP2_MCSPI_MODULCTRL_MS);
285 l |= OMAP2_MCSPI_MODULCTRL_SINGLE;
286 }
287 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l);
288
289 ctx->modulctrl = l;
290 }
291
omap2_mcspi_set_fifo(const struct spi_device * spi,struct spi_transfer * t,int enable)292 static void omap2_mcspi_set_fifo(const struct spi_device *spi,
293 struct spi_transfer *t, int enable)
294 {
295 struct spi_master *master = spi->master;
296 struct omap2_mcspi_cs *cs = spi->controller_state;
297 struct omap2_mcspi *mcspi;
298 unsigned int wcnt;
299 int max_fifo_depth, bytes_per_word;
300 u32 chconf, xferlevel;
301
302 mcspi = spi_master_get_devdata(master);
303
304 chconf = mcspi_cached_chconf0(spi);
305 if (enable) {
306 bytes_per_word = mcspi_bytes_per_word(cs->word_len);
307 if (t->len % bytes_per_word != 0)
308 goto disable_fifo;
309
310 if (t->rx_buf != NULL && t->tx_buf != NULL)
311 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH / 2;
312 else
313 max_fifo_depth = OMAP2_MCSPI_MAX_FIFODEPTH;
314
315 wcnt = t->len / bytes_per_word;
316 if (wcnt > OMAP2_MCSPI_MAX_FIFOWCNT)
317 goto disable_fifo;
318
319 xferlevel = wcnt << 16;
320 if (t->rx_buf != NULL) {
321 chconf |= OMAP2_MCSPI_CHCONF_FFER;
322 xferlevel |= (bytes_per_word - 1) << 8;
323 }
324
325 if (t->tx_buf != NULL) {
326 chconf |= OMAP2_MCSPI_CHCONF_FFET;
327 xferlevel |= bytes_per_word - 1;
328 }
329
330 mcspi_write_reg(master, OMAP2_MCSPI_XFERLEVEL, xferlevel);
331 mcspi_write_chconf0(spi, chconf);
332 mcspi->fifo_depth = max_fifo_depth;
333
334 return;
335 }
336
337 disable_fifo:
338 if (t->rx_buf != NULL)
339 chconf &= ~OMAP2_MCSPI_CHCONF_FFER;
340
341 if (t->tx_buf != NULL)
342 chconf &= ~OMAP2_MCSPI_CHCONF_FFET;
343
344 mcspi_write_chconf0(spi, chconf);
345 mcspi->fifo_depth = 0;
346 }
347
mcspi_wait_for_reg_bit(void __iomem * reg,unsigned long bit)348 static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit)
349 {
350 unsigned long timeout;
351
352 timeout = jiffies + msecs_to_jiffies(1000);
353 while (!(readl_relaxed(reg) & bit)) {
354 if (time_after(jiffies, timeout)) {
355 if (!(readl_relaxed(reg) & bit))
356 return -ETIMEDOUT;
357 else
358 return 0;
359 }
360 cpu_relax();
361 }
362 return 0;
363 }
364
mcspi_wait_for_completion(struct omap2_mcspi * mcspi,struct completion * x)365 static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi,
366 struct completion *x)
367 {
368 if (spi_controller_is_slave(mcspi->master)) {
369 if (wait_for_completion_interruptible(x) ||
370 mcspi->slave_aborted)
371 return -EINTR;
372 } else {
373 wait_for_completion(x);
374 }
375
376 return 0;
377 }
378
omap2_mcspi_rx_callback(void * data)379 static void omap2_mcspi_rx_callback(void *data)
380 {
381 struct spi_device *spi = data;
382 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
383 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
384
385 /* We must disable the DMA RX request */
386 omap2_mcspi_set_dma_req(spi, 1, 0);
387
388 complete(&mcspi_dma->dma_rx_completion);
389 }
390
omap2_mcspi_tx_callback(void * data)391 static void omap2_mcspi_tx_callback(void *data)
392 {
393 struct spi_device *spi = data;
394 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
395 struct omap2_mcspi_dma *mcspi_dma = &mcspi->dma_channels[spi->chip_select];
396
397 /* We must disable the DMA TX request */
398 omap2_mcspi_set_dma_req(spi, 0, 0);
399
400 complete(&mcspi_dma->dma_tx_completion);
401 }
402
omap2_mcspi_tx_dma(struct spi_device * spi,struct spi_transfer * xfer,struct dma_slave_config cfg)403 static void omap2_mcspi_tx_dma(struct spi_device *spi,
404 struct spi_transfer *xfer,
405 struct dma_slave_config cfg)
406 {
407 struct omap2_mcspi *mcspi;
408 struct omap2_mcspi_dma *mcspi_dma;
409 struct dma_async_tx_descriptor *tx;
410
411 mcspi = spi_master_get_devdata(spi->master);
412 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
413
414 dmaengine_slave_config(mcspi_dma->dma_tx, &cfg);
415
416 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_tx, xfer->tx_sg.sgl,
417 xfer->tx_sg.nents,
418 DMA_MEM_TO_DEV,
419 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
420 if (tx) {
421 tx->callback = omap2_mcspi_tx_callback;
422 tx->callback_param = spi;
423 dmaengine_submit(tx);
424 } else {
425 /* FIXME: fall back to PIO? */
426 }
427 dma_async_issue_pending(mcspi_dma->dma_tx);
428 omap2_mcspi_set_dma_req(spi, 0, 1);
429 }
430
431 static unsigned
omap2_mcspi_rx_dma(struct spi_device * spi,struct spi_transfer * xfer,struct dma_slave_config cfg,unsigned es)432 omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer,
433 struct dma_slave_config cfg,
434 unsigned es)
435 {
436 struct omap2_mcspi *mcspi;
437 struct omap2_mcspi_dma *mcspi_dma;
438 unsigned int count, transfer_reduction = 0;
439 struct scatterlist *sg_out[2];
440 int nb_sizes = 0, out_mapped_nents[2], ret, x;
441 size_t sizes[2];
442 u32 l;
443 int elements = 0;
444 int word_len, element_count;
445 struct omap2_mcspi_cs *cs = spi->controller_state;
446 void __iomem *chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
447 struct dma_async_tx_descriptor *tx;
448
449 mcspi = spi_master_get_devdata(spi->master);
450 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
451 count = xfer->len;
452
453 /*
454 * In the "End-of-Transfer Procedure" section for DMA RX in OMAP35x TRM
455 * it mentions reducing DMA transfer length by one element in master
456 * normal mode.
457 */
458 if (mcspi->fifo_depth == 0)
459 transfer_reduction = es;
460
461 word_len = cs->word_len;
462 l = mcspi_cached_chconf0(spi);
463
464 if (word_len <= 8)
465 element_count = count;
466 else if (word_len <= 16)
467 element_count = count >> 1;
468 else /* word_len <= 32 */
469 element_count = count >> 2;
470
471
472 dmaengine_slave_config(mcspi_dma->dma_rx, &cfg);
473
474 /*
475 * Reduce DMA transfer length by one more if McSPI is
476 * configured in turbo mode.
477 */
478 if ((l & OMAP2_MCSPI_CHCONF_TURBO) && mcspi->fifo_depth == 0)
479 transfer_reduction += es;
480
481 if (transfer_reduction) {
482 /* Split sgl into two. The second sgl won't be used. */
483 sizes[0] = count - transfer_reduction;
484 sizes[1] = transfer_reduction;
485 nb_sizes = 2;
486 } else {
487 /*
488 * Don't bother splitting the sgl. This essentially
489 * clones the original sgl.
490 */
491 sizes[0] = count;
492 nb_sizes = 1;
493 }
494
495 ret = sg_split(xfer->rx_sg.sgl, xfer->rx_sg.nents, 0, nb_sizes,
496 sizes, sg_out, out_mapped_nents, GFP_KERNEL);
497
498 if (ret < 0) {
499 dev_err(&spi->dev, "sg_split failed\n");
500 return 0;
501 }
502
503 tx = dmaengine_prep_slave_sg(mcspi_dma->dma_rx, sg_out[0],
504 out_mapped_nents[0], DMA_DEV_TO_MEM,
505 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
506 if (tx) {
507 tx->callback = omap2_mcspi_rx_callback;
508 tx->callback_param = spi;
509 dmaengine_submit(tx);
510 } else {
511 /* FIXME: fall back to PIO? */
512 }
513
514 dma_async_issue_pending(mcspi_dma->dma_rx);
515 omap2_mcspi_set_dma_req(spi, 1, 1);
516
517 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion);
518 if (ret || mcspi->slave_aborted) {
519 dmaengine_terminate_sync(mcspi_dma->dma_rx);
520 omap2_mcspi_set_dma_req(spi, 1, 0);
521 return 0;
522 }
523
524 for (x = 0; x < nb_sizes; x++)
525 kfree(sg_out[x]);
526
527 if (mcspi->fifo_depth > 0)
528 return count;
529
530 /*
531 * Due to the DMA transfer length reduction the missing bytes must
532 * be read manually to receive all of the expected data.
533 */
534 omap2_mcspi_set_enable(spi, 0);
535
536 elements = element_count - 1;
537
538 if (l & OMAP2_MCSPI_CHCONF_TURBO) {
539 elements--;
540
541 if (!mcspi_wait_for_reg_bit(chstat_reg,
542 OMAP2_MCSPI_CHSTAT_RXS)) {
543 u32 w;
544
545 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
546 if (word_len <= 8)
547 ((u8 *)xfer->rx_buf)[elements++] = w;
548 else if (word_len <= 16)
549 ((u16 *)xfer->rx_buf)[elements++] = w;
550 else /* word_len <= 32 */
551 ((u32 *)xfer->rx_buf)[elements++] = w;
552 } else {
553 int bytes_per_word = mcspi_bytes_per_word(word_len);
554 dev_err(&spi->dev, "DMA RX penultimate word empty\n");
555 count -= (bytes_per_word << 1);
556 omap2_mcspi_set_enable(spi, 1);
557 return count;
558 }
559 }
560 if (!mcspi_wait_for_reg_bit(chstat_reg, OMAP2_MCSPI_CHSTAT_RXS)) {
561 u32 w;
562
563 w = mcspi_read_cs_reg(spi, OMAP2_MCSPI_RX0);
564 if (word_len <= 8)
565 ((u8 *)xfer->rx_buf)[elements] = w;
566 else if (word_len <= 16)
567 ((u16 *)xfer->rx_buf)[elements] = w;
568 else /* word_len <= 32 */
569 ((u32 *)xfer->rx_buf)[elements] = w;
570 } else {
571 dev_err(&spi->dev, "DMA RX last word empty\n");
572 count -= mcspi_bytes_per_word(word_len);
573 }
574 omap2_mcspi_set_enable(spi, 1);
575 return count;
576 }
577
578 static unsigned
omap2_mcspi_txrx_dma(struct spi_device * spi,struct spi_transfer * xfer)579 omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer)
580 {
581 struct omap2_mcspi *mcspi;
582 struct omap2_mcspi_cs *cs = spi->controller_state;
583 struct omap2_mcspi_dma *mcspi_dma;
584 unsigned int count;
585 u8 *rx;
586 const u8 *tx;
587 struct dma_slave_config cfg;
588 enum dma_slave_buswidth width;
589 unsigned es;
590 void __iomem *chstat_reg;
591 void __iomem *irqstat_reg;
592 int wait_res;
593
594 mcspi = spi_master_get_devdata(spi->master);
595 mcspi_dma = &mcspi->dma_channels[spi->chip_select];
596
597 if (cs->word_len <= 8) {
598 width = DMA_SLAVE_BUSWIDTH_1_BYTE;
599 es = 1;
600 } else if (cs->word_len <= 16) {
601 width = DMA_SLAVE_BUSWIDTH_2_BYTES;
602 es = 2;
603 } else {
604 width = DMA_SLAVE_BUSWIDTH_4_BYTES;
605 es = 4;
606 }
607
608 count = xfer->len;
609
610 memset(&cfg, 0, sizeof(cfg));
611 cfg.src_addr = cs->phys + OMAP2_MCSPI_RX0;
612 cfg.dst_addr = cs->phys + OMAP2_MCSPI_TX0;
613 cfg.src_addr_width = width;
614 cfg.dst_addr_width = width;
615 cfg.src_maxburst = 1;
616 cfg.dst_maxburst = 1;
617
618 rx = xfer->rx_buf;
619 tx = xfer->tx_buf;
620
621 mcspi->slave_aborted = false;
622 reinit_completion(&mcspi_dma->dma_tx_completion);
623 reinit_completion(&mcspi_dma->dma_rx_completion);
624 reinit_completion(&mcspi->txdone);
625 if (tx) {
626 /* Enable EOW IRQ to know end of tx in slave mode */
627 if (spi_controller_is_slave(spi->master))
628 mcspi_write_reg(spi->master,
629 OMAP2_MCSPI_IRQENABLE,
630 OMAP2_MCSPI_IRQSTATUS_EOW);
631 omap2_mcspi_tx_dma(spi, xfer, cfg);
632 }
633
634 if (rx != NULL)
635 count = omap2_mcspi_rx_dma(spi, xfer, cfg, es);
636
637 if (tx != NULL) {
638 int ret;
639
640 ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion);
641 if (ret || mcspi->slave_aborted) {
642 dmaengine_terminate_sync(mcspi_dma->dma_tx);
643 omap2_mcspi_set_dma_req(spi, 0, 0);
644 return 0;
645 }
646
647 if (spi_controller_is_slave(mcspi->master)) {
648 ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone);
649 if (ret || mcspi->slave_aborted)
650 return 0;
651 }
652
653 if (mcspi->fifo_depth > 0) {
654 irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS;
655
656 if (mcspi_wait_for_reg_bit(irqstat_reg,
657 OMAP2_MCSPI_IRQSTATUS_EOW) < 0)
658 dev_err(&spi->dev, "EOW timed out\n");
659
660 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS,
661 OMAP2_MCSPI_IRQSTATUS_EOW);
662 }
663
664 /* for TX_ONLY mode, be sure all words have shifted out */
665 if (rx == NULL) {
666 chstat_reg = cs->base + OMAP2_MCSPI_CHSTAT0;
667 if (mcspi->fifo_depth > 0) {
668 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
669 OMAP2_MCSPI_CHSTAT_TXFFE);
670 if (wait_res < 0)
671 dev_err(&spi->dev, "TXFFE timed out\n");
672 } else {
673 wait_res = mcspi_wait_for_reg_bit(chstat_reg,
674 OMAP2_MCSPI_CHSTAT_TXS);
675 if (wait_res < 0)
676 dev_err(&spi->dev, "TXS timed out\n");
677 }
678 if (wait_res >= 0 &&
679 (mcspi_wait_for_reg_bit(chstat_reg,
680 OMAP2_MCSPI_CHSTAT_EOT) < 0))
681 dev_err(&spi->dev, "EOT timed out\n");
682 }
683 }
684 return count;
685 }
686
687 static unsigned
omap2_mcspi_txrx_pio(struct spi_device * spi,struct spi_transfer * xfer)688 omap2_mcspi_txrx_pio(struct spi_device *spi, struct spi_transfer *xfer)
689 {
690 struct omap2_mcspi_cs *cs = spi->controller_state;
691 unsigned int count, c;
692 u32 l;
693 void __iomem *base = cs->base;
694 void __iomem *tx_reg;
695 void __iomem *rx_reg;
696 void __iomem *chstat_reg;
697 int word_len;
698
699 count = xfer->len;
700 c = count;
701 word_len = cs->word_len;
702
703 l = mcspi_cached_chconf0(spi);
704
705 /* We store the pre-calculated register addresses on stack to speed
706 * up the transfer loop. */
707 tx_reg = base + OMAP2_MCSPI_TX0;
708 rx_reg = base + OMAP2_MCSPI_RX0;
709 chstat_reg = base + OMAP2_MCSPI_CHSTAT0;
710
711 if (c < (word_len>>3))
712 return 0;
713
714 if (word_len <= 8) {
715 u8 *rx;
716 const u8 *tx;
717
718 rx = xfer->rx_buf;
719 tx = xfer->tx_buf;
720
721 do {
722 c -= 1;
723 if (tx != NULL) {
724 if (mcspi_wait_for_reg_bit(chstat_reg,
725 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
726 dev_err(&spi->dev, "TXS timed out\n");
727 goto out;
728 }
729 dev_vdbg(&spi->dev, "write-%d %02x\n",
730 word_len, *tx);
731 writel_relaxed(*tx++, tx_reg);
732 }
733 if (rx != NULL) {
734 if (mcspi_wait_for_reg_bit(chstat_reg,
735 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
736 dev_err(&spi->dev, "RXS timed out\n");
737 goto out;
738 }
739
740 if (c == 1 && tx == NULL &&
741 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
742 omap2_mcspi_set_enable(spi, 0);
743 *rx++ = readl_relaxed(rx_reg);
744 dev_vdbg(&spi->dev, "read-%d %02x\n",
745 word_len, *(rx - 1));
746 if (mcspi_wait_for_reg_bit(chstat_reg,
747 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
748 dev_err(&spi->dev,
749 "RXS timed out\n");
750 goto out;
751 }
752 c = 0;
753 } else if (c == 0 && tx == NULL) {
754 omap2_mcspi_set_enable(spi, 0);
755 }
756
757 *rx++ = readl_relaxed(rx_reg);
758 dev_vdbg(&spi->dev, "read-%d %02x\n",
759 word_len, *(rx - 1));
760 }
761 } while (c);
762 } else if (word_len <= 16) {
763 u16 *rx;
764 const u16 *tx;
765
766 rx = xfer->rx_buf;
767 tx = xfer->tx_buf;
768 do {
769 c -= 2;
770 if (tx != NULL) {
771 if (mcspi_wait_for_reg_bit(chstat_reg,
772 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
773 dev_err(&spi->dev, "TXS timed out\n");
774 goto out;
775 }
776 dev_vdbg(&spi->dev, "write-%d %04x\n",
777 word_len, *tx);
778 writel_relaxed(*tx++, tx_reg);
779 }
780 if (rx != NULL) {
781 if (mcspi_wait_for_reg_bit(chstat_reg,
782 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
783 dev_err(&spi->dev, "RXS timed out\n");
784 goto out;
785 }
786
787 if (c == 2 && tx == NULL &&
788 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
789 omap2_mcspi_set_enable(spi, 0);
790 *rx++ = readl_relaxed(rx_reg);
791 dev_vdbg(&spi->dev, "read-%d %04x\n",
792 word_len, *(rx - 1));
793 if (mcspi_wait_for_reg_bit(chstat_reg,
794 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
795 dev_err(&spi->dev,
796 "RXS timed out\n");
797 goto out;
798 }
799 c = 0;
800 } else if (c == 0 && tx == NULL) {
801 omap2_mcspi_set_enable(spi, 0);
802 }
803
804 *rx++ = readl_relaxed(rx_reg);
805 dev_vdbg(&spi->dev, "read-%d %04x\n",
806 word_len, *(rx - 1));
807 }
808 } while (c >= 2);
809 } else if (word_len <= 32) {
810 u32 *rx;
811 const u32 *tx;
812
813 rx = xfer->rx_buf;
814 tx = xfer->tx_buf;
815 do {
816 c -= 4;
817 if (tx != NULL) {
818 if (mcspi_wait_for_reg_bit(chstat_reg,
819 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
820 dev_err(&spi->dev, "TXS timed out\n");
821 goto out;
822 }
823 dev_vdbg(&spi->dev, "write-%d %08x\n",
824 word_len, *tx);
825 writel_relaxed(*tx++, tx_reg);
826 }
827 if (rx != NULL) {
828 if (mcspi_wait_for_reg_bit(chstat_reg,
829 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
830 dev_err(&spi->dev, "RXS timed out\n");
831 goto out;
832 }
833
834 if (c == 4 && tx == NULL &&
835 (l & OMAP2_MCSPI_CHCONF_TURBO)) {
836 omap2_mcspi_set_enable(spi, 0);
837 *rx++ = readl_relaxed(rx_reg);
838 dev_vdbg(&spi->dev, "read-%d %08x\n",
839 word_len, *(rx - 1));
840 if (mcspi_wait_for_reg_bit(chstat_reg,
841 OMAP2_MCSPI_CHSTAT_RXS) < 0) {
842 dev_err(&spi->dev,
843 "RXS timed out\n");
844 goto out;
845 }
846 c = 0;
847 } else if (c == 0 && tx == NULL) {
848 omap2_mcspi_set_enable(spi, 0);
849 }
850
851 *rx++ = readl_relaxed(rx_reg);
852 dev_vdbg(&spi->dev, "read-%d %08x\n",
853 word_len, *(rx - 1));
854 }
855 } while (c >= 4);
856 }
857
858 /* for TX_ONLY mode, be sure all words have shifted out */
859 if (xfer->rx_buf == NULL) {
860 if (mcspi_wait_for_reg_bit(chstat_reg,
861 OMAP2_MCSPI_CHSTAT_TXS) < 0) {
862 dev_err(&spi->dev, "TXS timed out\n");
863 } else if (mcspi_wait_for_reg_bit(chstat_reg,
864 OMAP2_MCSPI_CHSTAT_EOT) < 0)
865 dev_err(&spi->dev, "EOT timed out\n");
866
867 /* disable chan to purge rx datas received in TX_ONLY transfer,
868 * otherwise these rx datas will affect the direct following
869 * RX_ONLY transfer.
870 */
871 omap2_mcspi_set_enable(spi, 0);
872 }
873 out:
874 omap2_mcspi_set_enable(spi, 1);
875 return count - c;
876 }
877
omap2_mcspi_calc_divisor(u32 speed_hz)878 static u32 omap2_mcspi_calc_divisor(u32 speed_hz)
879 {
880 u32 div;
881
882 for (div = 0; div < 15; div++)
883 if (speed_hz >= (OMAP2_MCSPI_MAX_FREQ >> div))
884 return div;
885
886 return 15;
887 }
888
889 /* called only when no transfer is active to this device */
omap2_mcspi_setup_transfer(struct spi_device * spi,struct spi_transfer * t)890 static int omap2_mcspi_setup_transfer(struct spi_device *spi,
891 struct spi_transfer *t)
892 {
893 struct omap2_mcspi_cs *cs = spi->controller_state;
894 struct omap2_mcspi *mcspi;
895 u32 l = 0, clkd = 0, div, extclk = 0, clkg = 0;
896 u8 word_len = spi->bits_per_word;
897 u32 speed_hz = spi->max_speed_hz;
898
899 mcspi = spi_master_get_devdata(spi->master);
900
901 if (t != NULL && t->bits_per_word)
902 word_len = t->bits_per_word;
903
904 cs->word_len = word_len;
905
906 if (t && t->speed_hz)
907 speed_hz = t->speed_hz;
908
909 speed_hz = min_t(u32, speed_hz, OMAP2_MCSPI_MAX_FREQ);
910 if (speed_hz < (OMAP2_MCSPI_MAX_FREQ / OMAP2_MCSPI_MAX_DIVIDER)) {
911 clkd = omap2_mcspi_calc_divisor(speed_hz);
912 speed_hz = OMAP2_MCSPI_MAX_FREQ >> clkd;
913 clkg = 0;
914 } else {
915 div = (OMAP2_MCSPI_MAX_FREQ + speed_hz - 1) / speed_hz;
916 speed_hz = OMAP2_MCSPI_MAX_FREQ / div;
917 clkd = (div - 1) & 0xf;
918 extclk = (div - 1) >> 4;
919 clkg = OMAP2_MCSPI_CHCONF_CLKG;
920 }
921
922 l = mcspi_cached_chconf0(spi);
923
924 /* standard 4-wire master mode: SCK, MOSI/out, MISO/in, nCS
925 * REVISIT: this controller could support SPI_3WIRE mode.
926 */
927 if (mcspi->pin_dir == MCSPI_PINDIR_D0_IN_D1_OUT) {
928 l &= ~OMAP2_MCSPI_CHCONF_IS;
929 l &= ~OMAP2_MCSPI_CHCONF_DPE1;
930 l |= OMAP2_MCSPI_CHCONF_DPE0;
931 } else {
932 l |= OMAP2_MCSPI_CHCONF_IS;
933 l |= OMAP2_MCSPI_CHCONF_DPE1;
934 l &= ~OMAP2_MCSPI_CHCONF_DPE0;
935 }
936
937 /* wordlength */
938 l &= ~OMAP2_MCSPI_CHCONF_WL_MASK;
939 l |= (word_len - 1) << 7;
940
941 /* set chipselect polarity; manage with FORCE */
942 if (!(spi->mode & SPI_CS_HIGH))
943 l |= OMAP2_MCSPI_CHCONF_EPOL; /* active-low; normal */
944 else
945 l &= ~OMAP2_MCSPI_CHCONF_EPOL;
946
947 /* set clock divisor */
948 l &= ~OMAP2_MCSPI_CHCONF_CLKD_MASK;
949 l |= clkd << 2;
950
951 /* set clock granularity */
952 l &= ~OMAP2_MCSPI_CHCONF_CLKG;
953 l |= clkg;
954 if (clkg) {
955 cs->chctrl0 &= ~OMAP2_MCSPI_CHCTRL_EXTCLK_MASK;
956 cs->chctrl0 |= extclk << 8;
957 mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCTRL0, cs->chctrl0);
958 }
959
960 /* set SPI mode 0..3 */
961 if (spi->mode & SPI_CPOL)
962 l |= OMAP2_MCSPI_CHCONF_POL;
963 else
964 l &= ~OMAP2_MCSPI_CHCONF_POL;
965 if (spi->mode & SPI_CPHA)
966 l |= OMAP2_MCSPI_CHCONF_PHA;
967 else
968 l &= ~OMAP2_MCSPI_CHCONF_PHA;
969
970 mcspi_write_chconf0(spi, l);
971
972 cs->mode = spi->mode;
973
974 dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",
975 speed_hz,
976 (spi->mode & SPI_CPHA) ? "trailing" : "leading",
977 (spi->mode & SPI_CPOL) ? "inverted" : "normal");
978
979 return 0;
980 }
981
982 /*
983 * Note that we currently allow DMA only if we get a channel
984 * for both rx and tx. Otherwise we'll do PIO for both rx and tx.
985 */
omap2_mcspi_request_dma(struct omap2_mcspi * mcspi,struct omap2_mcspi_dma * mcspi_dma)986 static int omap2_mcspi_request_dma(struct omap2_mcspi *mcspi,
987 struct omap2_mcspi_dma *mcspi_dma)
988 {
989 int ret = 0;
990
991 mcspi_dma->dma_rx = dma_request_chan(mcspi->dev,
992 mcspi_dma->dma_rx_ch_name);
993 if (IS_ERR(mcspi_dma->dma_rx)) {
994 ret = PTR_ERR(mcspi_dma->dma_rx);
995 mcspi_dma->dma_rx = NULL;
996 goto no_dma;
997 }
998
999 mcspi_dma->dma_tx = dma_request_chan(mcspi->dev,
1000 mcspi_dma->dma_tx_ch_name);
1001 if (IS_ERR(mcspi_dma->dma_tx)) {
1002 ret = PTR_ERR(mcspi_dma->dma_tx);
1003 mcspi_dma->dma_tx = NULL;
1004 dma_release_channel(mcspi_dma->dma_rx);
1005 mcspi_dma->dma_rx = NULL;
1006 }
1007
1008 init_completion(&mcspi_dma->dma_rx_completion);
1009 init_completion(&mcspi_dma->dma_tx_completion);
1010
1011 no_dma:
1012 return ret;
1013 }
1014
omap2_mcspi_release_dma(struct spi_master * master)1015 static void omap2_mcspi_release_dma(struct spi_master *master)
1016 {
1017 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1018 struct omap2_mcspi_dma *mcspi_dma;
1019 int i;
1020
1021 for (i = 0; i < master->num_chipselect; i++) {
1022 mcspi_dma = &mcspi->dma_channels[i];
1023
1024 if (mcspi_dma->dma_rx) {
1025 dma_release_channel(mcspi_dma->dma_rx);
1026 mcspi_dma->dma_rx = NULL;
1027 }
1028 if (mcspi_dma->dma_tx) {
1029 dma_release_channel(mcspi_dma->dma_tx);
1030 mcspi_dma->dma_tx = NULL;
1031 }
1032 }
1033 }
1034
omap2_mcspi_cleanup(struct spi_device * spi)1035 static void omap2_mcspi_cleanup(struct spi_device *spi)
1036 {
1037 struct omap2_mcspi_cs *cs;
1038
1039 if (spi->controller_state) {
1040 /* Unlink controller state from context save list */
1041 cs = spi->controller_state;
1042 list_del(&cs->node);
1043
1044 kfree(cs);
1045 }
1046 }
1047
omap2_mcspi_setup(struct spi_device * spi)1048 static int omap2_mcspi_setup(struct spi_device *spi)
1049 {
1050 bool initial_setup = false;
1051 int ret;
1052 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1053 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1054 struct omap2_mcspi_cs *cs = spi->controller_state;
1055
1056 if (!cs) {
1057 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
1058 if (!cs)
1059 return -ENOMEM;
1060 cs->base = mcspi->base + spi->chip_select * 0x14;
1061 cs->phys = mcspi->phys + spi->chip_select * 0x14;
1062 cs->mode = 0;
1063 cs->chconf0 = 0;
1064 cs->chctrl0 = 0;
1065 spi->controller_state = cs;
1066 /* Link this to context save list */
1067 list_add_tail(&cs->node, &ctx->cs);
1068 initial_setup = true;
1069 }
1070
1071 ret = pm_runtime_get_sync(mcspi->dev);
1072 if (ret < 0) {
1073 pm_runtime_put_noidle(mcspi->dev);
1074 if (initial_setup)
1075 omap2_mcspi_cleanup(spi);
1076
1077 return ret;
1078 }
1079
1080 ret = omap2_mcspi_setup_transfer(spi, NULL);
1081 if (ret && initial_setup)
1082 omap2_mcspi_cleanup(spi);
1083
1084 pm_runtime_mark_last_busy(mcspi->dev);
1085 pm_runtime_put_autosuspend(mcspi->dev);
1086
1087 return ret;
1088 }
1089
omap2_mcspi_irq_handler(int irq,void * data)1090 static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data)
1091 {
1092 struct omap2_mcspi *mcspi = data;
1093 u32 irqstat;
1094
1095 irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS);
1096 if (!irqstat)
1097 return IRQ_NONE;
1098
1099 /* Disable IRQ and wakeup slave xfer task */
1100 mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0);
1101 if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW)
1102 complete(&mcspi->txdone);
1103
1104 return IRQ_HANDLED;
1105 }
1106
omap2_mcspi_slave_abort(struct spi_master * master)1107 static int omap2_mcspi_slave_abort(struct spi_master *master)
1108 {
1109 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1110 struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels;
1111
1112 mcspi->slave_aborted = true;
1113 complete(&mcspi_dma->dma_rx_completion);
1114 complete(&mcspi_dma->dma_tx_completion);
1115 complete(&mcspi->txdone);
1116
1117 return 0;
1118 }
1119
omap2_mcspi_transfer_one(struct spi_master * master,struct spi_device * spi,struct spi_transfer * t)1120 static int omap2_mcspi_transfer_one(struct spi_master *master,
1121 struct spi_device *spi,
1122 struct spi_transfer *t)
1123 {
1124
1125 /* We only enable one channel at a time -- the one whose message is
1126 * -- although this controller would gladly
1127 * arbitrate among multiple channels. This corresponds to "single
1128 * channel" master mode. As a side effect, we need to manage the
1129 * chipselect with the FORCE bit ... CS != channel enable.
1130 */
1131
1132 struct omap2_mcspi *mcspi;
1133 struct omap2_mcspi_dma *mcspi_dma;
1134 struct omap2_mcspi_cs *cs;
1135 struct omap2_mcspi_device_config *cd;
1136 int par_override = 0;
1137 int status = 0;
1138 u32 chconf;
1139
1140 mcspi = spi_master_get_devdata(master);
1141 mcspi_dma = mcspi->dma_channels + spi->chip_select;
1142 cs = spi->controller_state;
1143 cd = spi->controller_data;
1144
1145 /*
1146 * The slave driver could have changed spi->mode in which case
1147 * it will be different from cs->mode (the current hardware setup).
1148 * If so, set par_override (even though its not a parity issue) so
1149 * omap2_mcspi_setup_transfer will be called to configure the hardware
1150 * with the correct mode on the first iteration of the loop below.
1151 */
1152 if (spi->mode != cs->mode)
1153 par_override = 1;
1154
1155 omap2_mcspi_set_enable(spi, 0);
1156
1157 if (spi->cs_gpiod)
1158 omap2_mcspi_set_cs(spi, spi->mode & SPI_CS_HIGH);
1159
1160 if (par_override ||
1161 (t->speed_hz != spi->max_speed_hz) ||
1162 (t->bits_per_word != spi->bits_per_word)) {
1163 par_override = 1;
1164 status = omap2_mcspi_setup_transfer(spi, t);
1165 if (status < 0)
1166 goto out;
1167 if (t->speed_hz == spi->max_speed_hz &&
1168 t->bits_per_word == spi->bits_per_word)
1169 par_override = 0;
1170 }
1171 if (cd && cd->cs_per_word) {
1172 chconf = mcspi->ctx.modulctrl;
1173 chconf &= ~OMAP2_MCSPI_MODULCTRL_SINGLE;
1174 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1175 mcspi->ctx.modulctrl =
1176 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1177 }
1178
1179 chconf = mcspi_cached_chconf0(spi);
1180 chconf &= ~OMAP2_MCSPI_CHCONF_TRM_MASK;
1181 chconf &= ~OMAP2_MCSPI_CHCONF_TURBO;
1182
1183 if (t->tx_buf == NULL)
1184 chconf |= OMAP2_MCSPI_CHCONF_TRM_RX_ONLY;
1185 else if (t->rx_buf == NULL)
1186 chconf |= OMAP2_MCSPI_CHCONF_TRM_TX_ONLY;
1187
1188 if (cd && cd->turbo_mode && t->tx_buf == NULL) {
1189 /* Turbo mode is for more than one word */
1190 if (t->len > ((cs->word_len + 7) >> 3))
1191 chconf |= OMAP2_MCSPI_CHCONF_TURBO;
1192 }
1193
1194 mcspi_write_chconf0(spi, chconf);
1195
1196 if (t->len) {
1197 unsigned count;
1198
1199 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1200 master->cur_msg_mapped &&
1201 master->can_dma(master, spi, t))
1202 omap2_mcspi_set_fifo(spi, t, 1);
1203
1204 omap2_mcspi_set_enable(spi, 1);
1205
1206 /* RX_ONLY mode needs dummy data in TX reg */
1207 if (t->tx_buf == NULL)
1208 writel_relaxed(0, cs->base
1209 + OMAP2_MCSPI_TX0);
1210
1211 if ((mcspi_dma->dma_rx && mcspi_dma->dma_tx) &&
1212 master->cur_msg_mapped &&
1213 master->can_dma(master, spi, t))
1214 count = omap2_mcspi_txrx_dma(spi, t);
1215 else
1216 count = omap2_mcspi_txrx_pio(spi, t);
1217
1218 if (count != t->len) {
1219 status = -EIO;
1220 goto out;
1221 }
1222 }
1223
1224 omap2_mcspi_set_enable(spi, 0);
1225
1226 if (mcspi->fifo_depth > 0)
1227 omap2_mcspi_set_fifo(spi, t, 0);
1228
1229 out:
1230 /* Restore defaults if they were overriden */
1231 if (par_override) {
1232 par_override = 0;
1233 status = omap2_mcspi_setup_transfer(spi, NULL);
1234 }
1235
1236 if (cd && cd->cs_per_word) {
1237 chconf = mcspi->ctx.modulctrl;
1238 chconf |= OMAP2_MCSPI_MODULCTRL_SINGLE;
1239 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, chconf);
1240 mcspi->ctx.modulctrl =
1241 mcspi_read_cs_reg(spi, OMAP2_MCSPI_MODULCTRL);
1242 }
1243
1244 omap2_mcspi_set_enable(spi, 0);
1245
1246 if (spi->cs_gpiod)
1247 omap2_mcspi_set_cs(spi, !(spi->mode & SPI_CS_HIGH));
1248
1249 if (mcspi->fifo_depth > 0 && t)
1250 omap2_mcspi_set_fifo(spi, t, 0);
1251
1252 return status;
1253 }
1254
omap2_mcspi_prepare_message(struct spi_master * master,struct spi_message * msg)1255 static int omap2_mcspi_prepare_message(struct spi_master *master,
1256 struct spi_message *msg)
1257 {
1258 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1259 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1260 struct omap2_mcspi_cs *cs;
1261
1262 /* Only a single channel can have the FORCE bit enabled
1263 * in its chconf0 register.
1264 * Scan all channels and disable them except the current one.
1265 * A FORCE can remain from a last transfer having cs_change enabled
1266 */
1267 list_for_each_entry(cs, &ctx->cs, node) {
1268 if (msg->spi->controller_state == cs)
1269 continue;
1270
1271 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) {
1272 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1273 writel_relaxed(cs->chconf0,
1274 cs->base + OMAP2_MCSPI_CHCONF0);
1275 readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0);
1276 }
1277 }
1278
1279 return 0;
1280 }
1281
omap2_mcspi_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)1282 static bool omap2_mcspi_can_dma(struct spi_master *master,
1283 struct spi_device *spi,
1284 struct spi_transfer *xfer)
1285 {
1286 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1287 struct omap2_mcspi_dma *mcspi_dma =
1288 &mcspi->dma_channels[spi->chip_select];
1289
1290 if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx)
1291 return false;
1292
1293 if (spi_controller_is_slave(master))
1294 return true;
1295
1296 master->dma_rx = mcspi_dma->dma_rx;
1297 master->dma_tx = mcspi_dma->dma_tx;
1298
1299 return (xfer->len >= DMA_MIN_BYTES);
1300 }
1301
omap2_mcspi_max_xfer_size(struct spi_device * spi)1302 static size_t omap2_mcspi_max_xfer_size(struct spi_device *spi)
1303 {
1304 struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master);
1305 struct omap2_mcspi_dma *mcspi_dma =
1306 &mcspi->dma_channels[spi->chip_select];
1307
1308 if (mcspi->max_xfer_len && mcspi_dma->dma_rx)
1309 return mcspi->max_xfer_len;
1310
1311 return SIZE_MAX;
1312 }
1313
omap2_mcspi_controller_setup(struct omap2_mcspi * mcspi)1314 static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi)
1315 {
1316 struct spi_master *master = mcspi->master;
1317 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1318 int ret = 0;
1319
1320 ret = pm_runtime_get_sync(mcspi->dev);
1321 if (ret < 0) {
1322 pm_runtime_put_noidle(mcspi->dev);
1323
1324 return ret;
1325 }
1326
1327 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE,
1328 OMAP2_MCSPI_WAKEUPENABLE_WKEN);
1329 ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN;
1330
1331 omap2_mcspi_set_mode(master);
1332 pm_runtime_mark_last_busy(mcspi->dev);
1333 pm_runtime_put_autosuspend(mcspi->dev);
1334 return 0;
1335 }
1336
omap_mcspi_runtime_suspend(struct device * dev)1337 static int omap_mcspi_runtime_suspend(struct device *dev)
1338 {
1339 int error;
1340
1341 error = pinctrl_pm_select_idle_state(dev);
1342 if (error)
1343 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1344
1345 return 0;
1346 }
1347
1348 /*
1349 * When SPI wake up from off-mode, CS is in activate state. If it was in
1350 * inactive state when driver was suspend, then force it to inactive state at
1351 * wake up.
1352 */
omap_mcspi_runtime_resume(struct device * dev)1353 static int omap_mcspi_runtime_resume(struct device *dev)
1354 {
1355 struct spi_master *master = dev_get_drvdata(dev);
1356 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1357 struct omap2_mcspi_regs *ctx = &mcspi->ctx;
1358 struct omap2_mcspi_cs *cs;
1359 int error;
1360
1361 error = pinctrl_pm_select_default_state(dev);
1362 if (error)
1363 dev_warn(dev, "%s: failed to set pins: %i\n", __func__, error);
1364
1365 /* McSPI: context restore */
1366 mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, ctx->modulctrl);
1367 mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, ctx->wakeupenable);
1368
1369 list_for_each_entry(cs, &ctx->cs, node) {
1370 /*
1371 * We need to toggle CS state for OMAP take this
1372 * change in account.
1373 */
1374 if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE) == 0) {
1375 cs->chconf0 |= OMAP2_MCSPI_CHCONF_FORCE;
1376 writel_relaxed(cs->chconf0,
1377 cs->base + OMAP2_MCSPI_CHCONF0);
1378 cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE;
1379 writel_relaxed(cs->chconf0,
1380 cs->base + OMAP2_MCSPI_CHCONF0);
1381 } else {
1382 writel_relaxed(cs->chconf0,
1383 cs->base + OMAP2_MCSPI_CHCONF0);
1384 }
1385 }
1386
1387 return 0;
1388 }
1389
1390 static struct omap2_mcspi_platform_config omap2_pdata = {
1391 .regs_offset = 0,
1392 };
1393
1394 static struct omap2_mcspi_platform_config omap4_pdata = {
1395 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1396 };
1397
1398 static struct omap2_mcspi_platform_config am654_pdata = {
1399 .regs_offset = OMAP4_MCSPI_REG_OFFSET,
1400 .max_xfer_len = SZ_4K - 1,
1401 };
1402
1403 static const struct of_device_id omap_mcspi_of_match[] = {
1404 {
1405 .compatible = "ti,omap2-mcspi",
1406 .data = &omap2_pdata,
1407 },
1408 {
1409 .compatible = "ti,omap4-mcspi",
1410 .data = &omap4_pdata,
1411 },
1412 {
1413 .compatible = "ti,am654-mcspi",
1414 .data = &am654_pdata,
1415 },
1416 { },
1417 };
1418 MODULE_DEVICE_TABLE(of, omap_mcspi_of_match);
1419
omap2_mcspi_probe(struct platform_device * pdev)1420 static int omap2_mcspi_probe(struct platform_device *pdev)
1421 {
1422 struct spi_master *master;
1423 const struct omap2_mcspi_platform_config *pdata;
1424 struct omap2_mcspi *mcspi;
1425 struct resource *r;
1426 int status = 0, i;
1427 u32 regs_offset = 0;
1428 struct device_node *node = pdev->dev.of_node;
1429 const struct of_device_id *match;
1430
1431 if (of_property_read_bool(node, "spi-slave"))
1432 master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi));
1433 else
1434 master = spi_alloc_master(&pdev->dev, sizeof(*mcspi));
1435 if (!master)
1436 return -ENOMEM;
1437
1438 /* the spi->mode bits understood by this driver: */
1439 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1440 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1441 master->setup = omap2_mcspi_setup;
1442 master->auto_runtime_pm = true;
1443 master->prepare_message = omap2_mcspi_prepare_message;
1444 master->can_dma = omap2_mcspi_can_dma;
1445 master->transfer_one = omap2_mcspi_transfer_one;
1446 master->set_cs = omap2_mcspi_set_cs;
1447 master->cleanup = omap2_mcspi_cleanup;
1448 master->slave_abort = omap2_mcspi_slave_abort;
1449 master->dev.of_node = node;
1450 master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ;
1451 master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15;
1452 master->use_gpio_descriptors = true;
1453
1454 platform_set_drvdata(pdev, master);
1455
1456 mcspi = spi_master_get_devdata(master);
1457 mcspi->master = master;
1458
1459 match = of_match_device(omap_mcspi_of_match, &pdev->dev);
1460 if (match) {
1461 u32 num_cs = 1; /* default number of chipselect */
1462 pdata = match->data;
1463
1464 of_property_read_u32(node, "ti,spi-num-cs", &num_cs);
1465 master->num_chipselect = num_cs;
1466 if (of_get_property(node, "ti,pindir-d0-out-d1-in", NULL))
1467 mcspi->pin_dir = MCSPI_PINDIR_D0_OUT_D1_IN;
1468 } else {
1469 pdata = dev_get_platdata(&pdev->dev);
1470 master->num_chipselect = pdata->num_cs;
1471 mcspi->pin_dir = pdata->pin_dir;
1472 }
1473 regs_offset = pdata->regs_offset;
1474 if (pdata->max_xfer_len) {
1475 mcspi->max_xfer_len = pdata->max_xfer_len;
1476 master->max_transfer_size = omap2_mcspi_max_xfer_size;
1477 }
1478
1479 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1480 mcspi->base = devm_ioremap_resource(&pdev->dev, r);
1481 if (IS_ERR(mcspi->base)) {
1482 status = PTR_ERR(mcspi->base);
1483 goto free_master;
1484 }
1485 mcspi->phys = r->start + regs_offset;
1486 mcspi->base += regs_offset;
1487
1488 mcspi->dev = &pdev->dev;
1489
1490 INIT_LIST_HEAD(&mcspi->ctx.cs);
1491
1492 mcspi->dma_channels = devm_kcalloc(&pdev->dev, master->num_chipselect,
1493 sizeof(struct omap2_mcspi_dma),
1494 GFP_KERNEL);
1495 if (mcspi->dma_channels == NULL) {
1496 status = -ENOMEM;
1497 goto free_master;
1498 }
1499
1500 for (i = 0; i < master->num_chipselect; i++) {
1501 sprintf(mcspi->dma_channels[i].dma_rx_ch_name, "rx%d", i);
1502 sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i);
1503
1504 status = omap2_mcspi_request_dma(mcspi,
1505 &mcspi->dma_channels[i]);
1506 if (status == -EPROBE_DEFER)
1507 goto free_master;
1508 }
1509
1510 status = platform_get_irq(pdev, 0);
1511 if (status == -EPROBE_DEFER)
1512 goto free_master;
1513 if (status < 0) {
1514 dev_err(&pdev->dev, "no irq resource found\n");
1515 goto free_master;
1516 }
1517 init_completion(&mcspi->txdone);
1518 status = devm_request_irq(&pdev->dev, status,
1519 omap2_mcspi_irq_handler, 0, pdev->name,
1520 mcspi);
1521 if (status) {
1522 dev_err(&pdev->dev, "Cannot request IRQ");
1523 goto free_master;
1524 }
1525
1526 pm_runtime_use_autosuspend(&pdev->dev);
1527 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
1528 pm_runtime_enable(&pdev->dev);
1529
1530 status = omap2_mcspi_controller_setup(mcspi);
1531 if (status < 0)
1532 goto disable_pm;
1533
1534 status = devm_spi_register_controller(&pdev->dev, master);
1535 if (status < 0)
1536 goto disable_pm;
1537
1538 return status;
1539
1540 disable_pm:
1541 pm_runtime_dont_use_autosuspend(&pdev->dev);
1542 pm_runtime_put_sync(&pdev->dev);
1543 pm_runtime_disable(&pdev->dev);
1544 free_master:
1545 omap2_mcspi_release_dma(master);
1546 spi_master_put(master);
1547 return status;
1548 }
1549
omap2_mcspi_remove(struct platform_device * pdev)1550 static int omap2_mcspi_remove(struct platform_device *pdev)
1551 {
1552 struct spi_master *master = platform_get_drvdata(pdev);
1553 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1554
1555 omap2_mcspi_release_dma(master);
1556
1557 pm_runtime_dont_use_autosuspend(mcspi->dev);
1558 pm_runtime_put_sync(mcspi->dev);
1559 pm_runtime_disable(&pdev->dev);
1560
1561 return 0;
1562 }
1563
1564 /* work with hotplug and coldplug */
1565 MODULE_ALIAS("platform:omap2_mcspi");
1566
omap2_mcspi_suspend(struct device * dev)1567 static int __maybe_unused omap2_mcspi_suspend(struct device *dev)
1568 {
1569 struct spi_master *master = dev_get_drvdata(dev);
1570 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1571 int error;
1572
1573 error = pinctrl_pm_select_sleep_state(dev);
1574 if (error)
1575 dev_warn(mcspi->dev, "%s: failed to set pins: %i\n",
1576 __func__, error);
1577
1578 error = spi_master_suspend(master);
1579 if (error)
1580 dev_warn(mcspi->dev, "%s: master suspend failed: %i\n",
1581 __func__, error);
1582
1583 return pm_runtime_force_suspend(dev);
1584 }
1585
omap2_mcspi_resume(struct device * dev)1586 static int __maybe_unused omap2_mcspi_resume(struct device *dev)
1587 {
1588 struct spi_master *master = dev_get_drvdata(dev);
1589 struct omap2_mcspi *mcspi = spi_master_get_devdata(master);
1590 int error;
1591
1592 error = spi_master_resume(master);
1593 if (error)
1594 dev_warn(mcspi->dev, "%s: master resume failed: %i\n",
1595 __func__, error);
1596
1597 return pm_runtime_force_resume(dev);
1598 }
1599
1600 static const struct dev_pm_ops omap2_mcspi_pm_ops = {
1601 SET_SYSTEM_SLEEP_PM_OPS(omap2_mcspi_suspend,
1602 omap2_mcspi_resume)
1603 .runtime_suspend = omap_mcspi_runtime_suspend,
1604 .runtime_resume = omap_mcspi_runtime_resume,
1605 };
1606
1607 static struct platform_driver omap2_mcspi_driver = {
1608 .driver = {
1609 .name = "omap2_mcspi",
1610 .pm = &omap2_mcspi_pm_ops,
1611 .of_match_table = omap_mcspi_of_match,
1612 },
1613 .probe = omap2_mcspi_probe,
1614 .remove = omap2_mcspi_remove,
1615 };
1616
1617 module_platform_driver(omap2_mcspi_driver);
1618 MODULE_LICENSE("GPL");
1619