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locking/refcounts: Include fewer headers in <linux/refcount.h>
[linux/fpc-iii.git] / drivers / spi / spi-fsl-dspi.c
blob0630962ce442ee09d82921f3f0130f60a541e37b
1 /*
2 * drivers/spi/spi-fsl-dspi.c
3 *
4 * Copyright 2013 Freescale Semiconductor, Inc.
5 *
6 * Freescale DSPI driver
7 * This file contains a driver for the Freescale DSPI
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 */
15
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/dmaengine.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/err.h>
21 #include <linux/errno.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/kernel.h>
25 #include <linux/math64.h>
26 #include <linux/module.h>
27 #include <linux/of.h>
28 #include <linux/of_device.h>
29 #include <linux/pinctrl/consumer.h>
30 #include <linux/platform_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/regmap.h>
33 #include <linux/sched.h>
34 #include <linux/spi/spi.h>
35 #include <linux/spi/spi-fsl-dspi.h>
36 #include <linux/spi/spi_bitbang.h>
37 #include <linux/time.h>
38
39 #define DRIVER_NAME "fsl-dspi"
40
41 #define TRAN_STATE_RX_VOID 0x01
42 #define TRAN_STATE_TX_VOID 0x02
43 #define TRAN_STATE_WORD_ODD_NUM 0x04
44
45 #define DSPI_FIFO_SIZE 4
46 #define DSPI_DMA_BUFSIZE (DSPI_FIFO_SIZE * 1024)
47
48 #define SPI_MCR 0x00
49 #define SPI_MCR_MASTER (1 << 31)
50 #define SPI_MCR_PCSIS (0x3F << 16)
51 #define SPI_MCR_CLR_TXF (1 << 11)
52 #define SPI_MCR_CLR_RXF (1 << 10)
53
54 #define SPI_TCR 0x08
55 #define SPI_TCR_GET_TCNT(x) (((x) & 0xffff0000) >> 16)
56
57 #define SPI_CTAR(x) (0x0c + (((x) & 0x3) * 4))
58 #define SPI_CTAR_FMSZ(x) (((x) & 0x0000000f) << 27)
59 #define SPI_CTAR_CPOL(x) ((x) << 26)
60 #define SPI_CTAR_CPHA(x) ((x) << 25)
61 #define SPI_CTAR_LSBFE(x) ((x) << 24)
62 #define SPI_CTAR_PCSSCK(x) (((x) & 0x00000003) << 22)
63 #define SPI_CTAR_PASC(x) (((x) & 0x00000003) << 20)
64 #define SPI_CTAR_PDT(x) (((x) & 0x00000003) << 18)
65 #define SPI_CTAR_PBR(x) (((x) & 0x00000003) << 16)
66 #define SPI_CTAR_CSSCK(x) (((x) & 0x0000000f) << 12)
67 #define SPI_CTAR_ASC(x) (((x) & 0x0000000f) << 8)
68 #define SPI_CTAR_DT(x) (((x) & 0x0000000f) << 4)
69 #define SPI_CTAR_BR(x) ((x) & 0x0000000f)
70 #define SPI_CTAR_SCALE_BITS 0xf
71
72 #define SPI_CTAR0_SLAVE 0x0c
73
74 #define SPI_SR 0x2c
75 #define SPI_SR_EOQF 0x10000000
76 #define SPI_SR_TCFQF 0x80000000
77 #define SPI_SR_CLEAR 0xdaad0000
78
79 #define SPI_RSER_TFFFE BIT(25)
80 #define SPI_RSER_TFFFD BIT(24)
81 #define SPI_RSER_RFDFE BIT(17)
82 #define SPI_RSER_RFDFD BIT(16)
83
84 #define SPI_RSER 0x30
85 #define SPI_RSER_EOQFE 0x10000000
86 #define SPI_RSER_TCFQE 0x80000000
87
88 #define SPI_PUSHR 0x34
89 #define SPI_PUSHR_CONT (1 << 31)
90 #define SPI_PUSHR_CTAS(x) (((x) & 0x00000003) << 28)
91 #define SPI_PUSHR_EOQ (1 << 27)
92 #define SPI_PUSHR_CTCNT (1 << 26)
93 #define SPI_PUSHR_PCS(x) (((1 << x) & 0x0000003f) << 16)
94 #define SPI_PUSHR_TXDATA(x) ((x) & 0x0000ffff)
95
96 #define SPI_PUSHR_SLAVE 0x34
97
98 #define SPI_POPR 0x38
99 #define SPI_POPR_RXDATA(x) ((x) & 0x0000ffff)
100
101 #define SPI_TXFR0 0x3c
102 #define SPI_TXFR1 0x40
103 #define SPI_TXFR2 0x44
104 #define SPI_TXFR3 0x48
105 #define SPI_RXFR0 0x7c
106 #define SPI_RXFR1 0x80
107 #define SPI_RXFR2 0x84
108 #define SPI_RXFR3 0x88
109
110 #define SPI_FRAME_BITS(bits) SPI_CTAR_FMSZ((bits) - 1)
111 #define SPI_FRAME_BITS_MASK SPI_CTAR_FMSZ(0xf)
112 #define SPI_FRAME_BITS_16 SPI_CTAR_FMSZ(0xf)
113 #define SPI_FRAME_BITS_8 SPI_CTAR_FMSZ(0x7)
114
115 #define SPI_CS_INIT 0x01
116 #define SPI_CS_ASSERT 0x02
117 #define SPI_CS_DROP 0x04
118
119 #define SPI_TCR_TCNT_MAX 0x10000
120
121 #define DMA_COMPLETION_TIMEOUT msecs_to_jiffies(3000)
122
123 struct chip_data {
124 u32 mcr_val;
125 u32 ctar_val;
126 u16 void_write_data;
127 };
128
129 enum dspi_trans_mode {
130 DSPI_EOQ_MODE = 0,
131 DSPI_TCFQ_MODE,
132 DSPI_DMA_MODE,
133 };
134
135 struct fsl_dspi_devtype_data {
136 enum dspi_trans_mode trans_mode;
137 u8 max_clock_factor;
138 };
139
140 static const struct fsl_dspi_devtype_data vf610_data = {
141 .trans_mode = DSPI_DMA_MODE,
142 .max_clock_factor = 2,
143 };
144
145 static const struct fsl_dspi_devtype_data ls1021a_v1_data = {
146 .trans_mode = DSPI_TCFQ_MODE,
147 .max_clock_factor = 8,
148 };
149
150 static const struct fsl_dspi_devtype_data ls2085a_data = {
151 .trans_mode = DSPI_TCFQ_MODE,
152 .max_clock_factor = 8,
153 };
154
155 static const struct fsl_dspi_devtype_data coldfire_data = {
156 .trans_mode = DSPI_EOQ_MODE,
157 .max_clock_factor = 8,
158 };
159
160 struct fsl_dspi_dma {
161 /* Length of transfer in words of DSPI_FIFO_SIZE */
162 u32 curr_xfer_len;
163
164 u32 *tx_dma_buf;
165 struct dma_chan *chan_tx;
166 dma_addr_t tx_dma_phys;
167 struct completion cmd_tx_complete;
168 struct dma_async_tx_descriptor *tx_desc;
169
170 u32 *rx_dma_buf;
171 struct dma_chan *chan_rx;
172 dma_addr_t rx_dma_phys;
173 struct completion cmd_rx_complete;
174 struct dma_async_tx_descriptor *rx_desc;
175 };
176
177 struct fsl_dspi {
178 struct spi_master *master;
179 struct platform_device *pdev;
180
181 struct regmap *regmap;
182 int irq;
183 struct clk *clk;
184
185 struct spi_transfer *cur_transfer;
186 struct spi_message *cur_msg;
187 struct chip_data *cur_chip;
188 size_t len;
189 void *tx;
190 void *tx_end;
191 void *rx;
192 void *rx_end;
193 char dataflags;
194 u8 cs;
195 u16 void_write_data;
196 u32 cs_change;
197 const struct fsl_dspi_devtype_data *devtype_data;
198
199 wait_queue_head_t waitq;
200 u32 waitflags;
201
202 u32 spi_tcnt;
203 struct fsl_dspi_dma *dma;
204 };
205
206 static u32 dspi_data_to_pushr(struct fsl_dspi *dspi, int tx_word);
207
208 static inline int is_double_byte_mode(struct fsl_dspi *dspi)
209 {
210 unsigned int val;
211
212 regmap_read(dspi->regmap, SPI_CTAR(0), &val);
213
214 return ((val & SPI_FRAME_BITS_MASK) == SPI_FRAME_BITS(8)) ? 0 : 1;
215 }
216
217 static void dspi_tx_dma_callback(void *arg)
218 {
219 struct fsl_dspi *dspi = arg;
220 struct fsl_dspi_dma *dma = dspi->dma;
221
222 complete(&dma->cmd_tx_complete);
223 }
224
225 static void dspi_rx_dma_callback(void *arg)
226 {
227 struct fsl_dspi *dspi = arg;
228 struct fsl_dspi_dma *dma = dspi->dma;
229 int rx_word;
230 int i;
231 u16 d;
232
233 rx_word = is_double_byte_mode(dspi);
234
235 if (!(dspi->dataflags & TRAN_STATE_RX_VOID)) {
236 for (i = 0; i < dma->curr_xfer_len; i++) {
237 d = dspi->dma->rx_dma_buf[i];
238 rx_word ? (*(u16 *)dspi->rx = d) :
239 (*(u8 *)dspi->rx = d);
240 dspi->rx += rx_word + 1;
241 }
242 }
243
244 complete(&dma->cmd_rx_complete);
245 }
246
247 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
248 {
249 struct fsl_dspi_dma *dma = dspi->dma;
250 struct device *dev = &dspi->pdev->dev;
251 int time_left;
252 int tx_word;
253 int i;
254
255 tx_word = is_double_byte_mode(dspi);
256
257 for (i = 0; i < dma->curr_xfer_len; i++) {
258 dspi->dma->tx_dma_buf[i] = dspi_data_to_pushr(dspi, tx_word);
259 if ((dspi->cs_change) && (!dspi->len))
260 dspi->dma->tx_dma_buf[i] &= ~SPI_PUSHR_CONT;
261 }
262
263 dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
264 dma->tx_dma_phys,
265 dma->curr_xfer_len *
266 DMA_SLAVE_BUSWIDTH_4_BYTES,
267 DMA_MEM_TO_DEV,
268 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
269 if (!dma->tx_desc) {
270 dev_err(dev, "Not able to get desc for DMA xfer\n");
271 return -EIO;
272 }
273
274 dma->tx_desc->callback = dspi_tx_dma_callback;
275 dma->tx_desc->callback_param = dspi;
276 if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
277 dev_err(dev, "DMA submit failed\n");
278 return -EINVAL;
279 }
280
281 dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
282 dma->rx_dma_phys,
283 dma->curr_xfer_len *
284 DMA_SLAVE_BUSWIDTH_4_BYTES,
285 DMA_DEV_TO_MEM,
286 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
287 if (!dma->rx_desc) {
288 dev_err(dev, "Not able to get desc for DMA xfer\n");
289 return -EIO;
290 }
291
292 dma->rx_desc->callback = dspi_rx_dma_callback;
293 dma->rx_desc->callback_param = dspi;
294 if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
295 dev_err(dev, "DMA submit failed\n");
296 return -EINVAL;
297 }
298
299 reinit_completion(&dspi->dma->cmd_rx_complete);
300 reinit_completion(&dspi->dma->cmd_tx_complete);
301
302 dma_async_issue_pending(dma->chan_rx);
303 dma_async_issue_pending(dma->chan_tx);
304
305 time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
306 DMA_COMPLETION_TIMEOUT);
307 if (time_left == 0) {
308 dev_err(dev, "DMA tx timeout\n");
309 dmaengine_terminate_all(dma->chan_tx);
310 dmaengine_terminate_all(dma->chan_rx);
311 return -ETIMEDOUT;
312 }
313
314 time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
315 DMA_COMPLETION_TIMEOUT);
316 if (time_left == 0) {
317 dev_err(dev, "DMA rx timeout\n");
318 dmaengine_terminate_all(dma->chan_tx);
319 dmaengine_terminate_all(dma->chan_rx);
320 return -ETIMEDOUT;
321 }
322
323 return 0;
324 }
325
326 static int dspi_dma_xfer(struct fsl_dspi *dspi)
327 {
328 struct fsl_dspi_dma *dma = dspi->dma;
329 struct device *dev = &dspi->pdev->dev;
330 int curr_remaining_bytes;
331 int bytes_per_buffer;
332 int word = 1;
333 int ret = 0;
334
335 if (is_double_byte_mode(dspi))
336 word = 2;
337 curr_remaining_bytes = dspi->len;
338 bytes_per_buffer = DSPI_DMA_BUFSIZE / DSPI_FIFO_SIZE;
339 while (curr_remaining_bytes) {
340 /* Check if current transfer fits the DMA buffer */
341 dma->curr_xfer_len = curr_remaining_bytes / word;
342 if (dma->curr_xfer_len > bytes_per_buffer)
343 dma->curr_xfer_len = bytes_per_buffer;
344
345 ret = dspi_next_xfer_dma_submit(dspi);
346 if (ret) {
347 dev_err(dev, "DMA transfer failed\n");
348 goto exit;
349
350 } else {
351 curr_remaining_bytes -= dma->curr_xfer_len * word;
352 if (curr_remaining_bytes < 0)
353 curr_remaining_bytes = 0;
354 }
355 }
356
357 exit:
358 return ret;
359 }
360
361 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
362 {
363 struct fsl_dspi_dma *dma;
364 struct dma_slave_config cfg;
365 struct device *dev = &dspi->pdev->dev;
366 int ret;
367
368 dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
369 if (!dma)
370 return -ENOMEM;
371
372 dma->chan_rx = dma_request_slave_channel(dev, "rx");
373 if (!dma->chan_rx) {
374 dev_err(dev, "rx dma channel not available\n");
375 ret = -ENODEV;
376 return ret;
377 }
378
379 dma->chan_tx = dma_request_slave_channel(dev, "tx");
380 if (!dma->chan_tx) {
381 dev_err(dev, "tx dma channel not available\n");
382 ret = -ENODEV;
383 goto err_tx_channel;
384 }
385
386 dma->tx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
387 &dma->tx_dma_phys, GFP_KERNEL);
388 if (!dma->tx_dma_buf) {
389 ret = -ENOMEM;
390 goto err_tx_dma_buf;
391 }
392
393 dma->rx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
394 &dma->rx_dma_phys, GFP_KERNEL);
395 if (!dma->rx_dma_buf) {
396 ret = -ENOMEM;
397 goto err_rx_dma_buf;
398 }
399
400 cfg.src_addr = phy_addr + SPI_POPR;
401 cfg.dst_addr = phy_addr + SPI_PUSHR;
402 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
403 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
404 cfg.src_maxburst = 1;
405 cfg.dst_maxburst = 1;
406
407 cfg.direction = DMA_DEV_TO_MEM;
408 ret = dmaengine_slave_config(dma->chan_rx, &cfg);
409 if (ret) {
410 dev_err(dev, "can't configure rx dma channel\n");
411 ret = -EINVAL;
412 goto err_slave_config;
413 }
414
415 cfg.direction = DMA_MEM_TO_DEV;
416 ret = dmaengine_slave_config(dma->chan_tx, &cfg);
417 if (ret) {
418 dev_err(dev, "can't configure tx dma channel\n");
419 ret = -EINVAL;
420 goto err_slave_config;
421 }
422
423 dspi->dma = dma;
424 init_completion(&dma->cmd_tx_complete);
425 init_completion(&dma->cmd_rx_complete);
426
427 return 0;
428
429 err_slave_config:
430 dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
431 dma->rx_dma_buf, dma->rx_dma_phys);
432 err_rx_dma_buf:
433 dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
434 dma->tx_dma_buf, dma->tx_dma_phys);
435 err_tx_dma_buf:
436 dma_release_channel(dma->chan_tx);
437 err_tx_channel:
438 dma_release_channel(dma->chan_rx);
439
440 devm_kfree(dev, dma);
441 dspi->dma = NULL;
442
443 return ret;
444 }
445
446 static void dspi_release_dma(struct fsl_dspi *dspi)
447 {
448 struct fsl_dspi_dma *dma = dspi->dma;
449 struct device *dev = &dspi->pdev->dev;
450
451 if (dma) {
452 if (dma->chan_tx) {
453 dma_unmap_single(dev, dma->tx_dma_phys,
454 DSPI_DMA_BUFSIZE, DMA_TO_DEVICE);
455 dma_release_channel(dma->chan_tx);
456 }
457
458 if (dma->chan_rx) {
459 dma_unmap_single(dev, dma->rx_dma_phys,
460 DSPI_DMA_BUFSIZE, DMA_FROM_DEVICE);
461 dma_release_channel(dma->chan_rx);
462 }
463 }
464 }
465
466 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
467 unsigned long clkrate)
468 {
469 /* Valid baud rate pre-scaler values */
470 int pbr_tbl[4] = {2, 3, 5, 7};
471 int brs[16] = { 2, 4, 6, 8,
472 16, 32, 64, 128,
473 256, 512, 1024, 2048,
474 4096, 8192, 16384, 32768 };
475 int scale_needed, scale, minscale = INT_MAX;
476 int i, j;
477
478 scale_needed = clkrate / speed_hz;
479 if (clkrate % speed_hz)
480 scale_needed++;
481
482 for (i = 0; i < ARRAY_SIZE(brs); i++)
483 for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
484 scale = brs[i] * pbr_tbl[j];
485 if (scale >= scale_needed) {
486 if (scale < minscale) {
487 minscale = scale;
488 *br = i;
489 *pbr = j;
490 }
491 break;
492 }
493 }
494
495 if (minscale == INT_MAX) {
496 pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
497 speed_hz, clkrate);
498 *pbr = ARRAY_SIZE(pbr_tbl) - 1;
499 *br = ARRAY_SIZE(brs) - 1;
500 }
501 }
502
503 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
504 unsigned long clkrate)
505 {
506 int pscale_tbl[4] = {1, 3, 5, 7};
507 int scale_needed, scale, minscale = INT_MAX;
508 int i, j;
509 u32 remainder;
510
511 scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
512 &remainder);
513 if (remainder)
514 scale_needed++;
515
516 for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
517 for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
518 scale = pscale_tbl[i] * (2 << j);
519 if (scale >= scale_needed) {
520 if (scale < minscale) {
521 minscale = scale;
522 *psc = i;
523 *sc = j;
524 }
525 break;
526 }
527 }
528
529 if (minscale == INT_MAX) {
530 pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
531 delay_ns, clkrate);
532 *psc = ARRAY_SIZE(pscale_tbl) - 1;
533 *sc = SPI_CTAR_SCALE_BITS;
534 }
535 }
536
537 static u32 dspi_data_to_pushr(struct fsl_dspi *dspi, int tx_word)
538 {
539 u16 d16;
540
541 if (!(dspi->dataflags & TRAN_STATE_TX_VOID))
542 d16 = tx_word ? *(u16 *)dspi->tx : *(u8 *)dspi->tx;
543 else
544 d16 = dspi->void_write_data;
545
546 dspi->tx += tx_word + 1;
547 dspi->len -= tx_word + 1;
548
549 return SPI_PUSHR_TXDATA(d16) |
550 SPI_PUSHR_PCS(dspi->cs) |
551 SPI_PUSHR_CTAS(0) |
552 SPI_PUSHR_CONT;
553 }
554
555 static void dspi_data_from_popr(struct fsl_dspi *dspi, int rx_word)
556 {
557 u16 d;
558 unsigned int val;
559
560 regmap_read(dspi->regmap, SPI_POPR, &val);
561 d = SPI_POPR_RXDATA(val);
562
563 if (!(dspi->dataflags & TRAN_STATE_RX_VOID))
564 rx_word ? (*(u16 *)dspi->rx = d) : (*(u8 *)dspi->rx = d);
565
566 dspi->rx += rx_word + 1;
567 }
568
569 static int dspi_eoq_write(struct fsl_dspi *dspi)
570 {
571 int tx_count = 0;
572 int tx_word;
573 u32 dspi_pushr = 0;
574
575 tx_word = is_double_byte_mode(dspi);
576
577 while (dspi->len && (tx_count < DSPI_FIFO_SIZE)) {
578 /* If we are in word mode, only have a single byte to transfer
579 * switch to byte mode temporarily. Will switch back at the
580 * end of the transfer.
581 */
582 if (tx_word && (dspi->len == 1)) {
583 dspi->dataflags |= TRAN_STATE_WORD_ODD_NUM;
584 regmap_update_bits(dspi->regmap, SPI_CTAR(0),
585 SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(8));
586 tx_word = 0;
587 }
588
589 dspi_pushr = dspi_data_to_pushr(dspi, tx_word);
590
591 if (dspi->len == 0 || tx_count == DSPI_FIFO_SIZE - 1) {
592 /* last transfer in the transfer */
593 dspi_pushr |= SPI_PUSHR_EOQ;
594 if ((dspi->cs_change) && (!dspi->len))
595 dspi_pushr &= ~SPI_PUSHR_CONT;
596 } else if (tx_word && (dspi->len == 1))
597 dspi_pushr |= SPI_PUSHR_EOQ;
598
599 regmap_write(dspi->regmap, SPI_PUSHR, dspi_pushr);
600
601 tx_count++;
602 }
603
604 return tx_count * (tx_word + 1);
605 }
606
607 static int dspi_eoq_read(struct fsl_dspi *dspi)
608 {
609 int rx_count = 0;
610 int rx_word = is_double_byte_mode(dspi);
611
612 while ((dspi->rx < dspi->rx_end)
613 && (rx_count < DSPI_FIFO_SIZE)) {
614 if (rx_word && (dspi->rx_end - dspi->rx) == 1)
615 rx_word = 0;
616
617 dspi_data_from_popr(dspi, rx_word);
618 rx_count++;
619 }
620
621 return rx_count;
622 }
623
624 static int dspi_tcfq_write(struct fsl_dspi *dspi)
625 {
626 int tx_word;
627 u32 dspi_pushr = 0;
628
629 tx_word = is_double_byte_mode(dspi);
630
631 if (tx_word && (dspi->len == 1)) {
632 dspi->dataflags |= TRAN_STATE_WORD_ODD_NUM;
633 regmap_update_bits(dspi->regmap, SPI_CTAR(0),
634 SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(8));
635 tx_word = 0;
636 }
637
638 dspi_pushr = dspi_data_to_pushr(dspi, tx_word);
639
640 if ((dspi->cs_change) && (!dspi->len))
641 dspi_pushr &= ~SPI_PUSHR_CONT;
642
643 regmap_write(dspi->regmap, SPI_PUSHR, dspi_pushr);
644
645 return tx_word + 1;
646 }
647
648 static void dspi_tcfq_read(struct fsl_dspi *dspi)
649 {
650 int rx_word = is_double_byte_mode(dspi);
651
652 if (rx_word && (dspi->rx_end - dspi->rx) == 1)
653 rx_word = 0;
654
655 dspi_data_from_popr(dspi, rx_word);
656 }
657
658 static int dspi_transfer_one_message(struct spi_master *master,
659 struct spi_message *message)
660 {
661 struct fsl_dspi *dspi = spi_master_get_devdata(master);
662 struct spi_device *spi = message->spi;
663 struct spi_transfer *transfer;
664 int status = 0;
665 enum dspi_trans_mode trans_mode;
666 u32 spi_tcr;
667
668 regmap_read(dspi->regmap, SPI_TCR, &spi_tcr);
669 dspi->spi_tcnt = SPI_TCR_GET_TCNT(spi_tcr);
670
671 message->actual_length = 0;
672
673 list_for_each_entry(transfer, &message->transfers, transfer_list) {
674 dspi->cur_transfer = transfer;
675 dspi->cur_msg = message;
676 dspi->cur_chip = spi_get_ctldata(spi);
677 dspi->cs = spi->chip_select;
678 dspi->cs_change = 0;
679 if (list_is_last(&dspi->cur_transfer->transfer_list,
680 &dspi->cur_msg->transfers) || transfer->cs_change)
681 dspi->cs_change = 1;
682 dspi->void_write_data = dspi->cur_chip->void_write_data;
683
684 dspi->dataflags = 0;
685 dspi->tx = (void *)transfer->tx_buf;
686 dspi->tx_end = dspi->tx + transfer->len;
687 dspi->rx = transfer->rx_buf;
688 dspi->rx_end = dspi->rx + transfer->len;
689 dspi->len = transfer->len;
690
691 if (!dspi->rx)
692 dspi->dataflags |= TRAN_STATE_RX_VOID;
693
694 if (!dspi->tx)
695 dspi->dataflags |= TRAN_STATE_TX_VOID;
696
697 regmap_write(dspi->regmap, SPI_MCR, dspi->cur_chip->mcr_val);
698 regmap_update_bits(dspi->regmap, SPI_MCR,
699 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
700 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
701 regmap_write(dspi->regmap, SPI_CTAR(0),
702 dspi->cur_chip->ctar_val);
703
704 trans_mode = dspi->devtype_data->trans_mode;
705 switch (trans_mode) {
706 case DSPI_EOQ_MODE:
707 regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
708 dspi_eoq_write(dspi);
709 break;
710 case DSPI_TCFQ_MODE:
711 regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_TCFQE);
712 dspi_tcfq_write(dspi);
713 break;
714 case DSPI_DMA_MODE:
715 regmap_write(dspi->regmap, SPI_RSER,
716 SPI_RSER_TFFFE | SPI_RSER_TFFFD |
717 SPI_RSER_RFDFE | SPI_RSER_RFDFD);
718 status = dspi_dma_xfer(dspi);
719 break;
720 default:
721 dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
722 trans_mode);
723 status = -EINVAL;
724 goto out;
725 }
726
727 if (trans_mode != DSPI_DMA_MODE) {
728 if (wait_event_interruptible(dspi->waitq,
729 dspi->waitflags))
730 dev_err(&dspi->pdev->dev,
731 "wait transfer complete fail!\n");
732 dspi->waitflags = 0;
733 }
734
735 if (transfer->delay_usecs)
736 udelay(transfer->delay_usecs);
737 }
738
739 out:
740 message->status = status;
741 spi_finalize_current_message(master);
742
743 return status;
744 }
745
746 static int dspi_setup(struct spi_device *spi)
747 {
748 struct chip_data *chip;
749 struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
750 struct fsl_dspi_platform_data *pdata;
751 u32 cs_sck_delay = 0, sck_cs_delay = 0;
752 unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
753 unsigned char pasc = 0, asc = 0, fmsz = 0;
754 unsigned long clkrate;
755
756 if ((spi->bits_per_word >= 4) && (spi->bits_per_word <= 16)) {
757 fmsz = spi->bits_per_word - 1;
758 } else {
759 pr_err("Invalid wordsize\n");
760 return -ENODEV;
761 }
762
763 /* Only alloc on first setup */
764 chip = spi_get_ctldata(spi);
765 if (chip == NULL) {
766 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
767 if (!chip)
768 return -ENOMEM;
769 }
770
771 pdata = dev_get_platdata(&dspi->pdev->dev);
772
773 if (!pdata) {
774 of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay",
775 &cs_sck_delay);
776
777 of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay",
778 &sck_cs_delay);
779 } else {
780 cs_sck_delay = pdata->cs_sck_delay;
781 sck_cs_delay = pdata->sck_cs_delay;
782 }
783
784 chip->mcr_val = SPI_MCR_MASTER | SPI_MCR_PCSIS |
785 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF;
786
787 chip->void_write_data = 0;
788
789 clkrate = clk_get_rate(dspi->clk);
790 hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
791
792 /* Set PCS to SCK delay scale values */
793 ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
794
795 /* Set After SCK delay scale values */
796 ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
797
798 chip->ctar_val = SPI_CTAR_FMSZ(fmsz)
799 | SPI_CTAR_CPOL(spi->mode & SPI_CPOL ? 1 : 0)
800 | SPI_CTAR_CPHA(spi->mode & SPI_CPHA ? 1 : 0)
801 | SPI_CTAR_LSBFE(spi->mode & SPI_LSB_FIRST ? 1 : 0)
802 | SPI_CTAR_PCSSCK(pcssck)
803 | SPI_CTAR_CSSCK(cssck)
804 | SPI_CTAR_PASC(pasc)
805 | SPI_CTAR_ASC(asc)
806 | SPI_CTAR_PBR(pbr)
807 | SPI_CTAR_BR(br);
808
809 spi_set_ctldata(spi, chip);
810
811 return 0;
812 }
813
814 static void dspi_cleanup(struct spi_device *spi)
815 {
816 struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
817
818 dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
819 spi->master->bus_num, spi->chip_select);
820
821 kfree(chip);
822 }
823
824 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
825 {
826 struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
827 struct spi_message *msg = dspi->cur_msg;
828 enum dspi_trans_mode trans_mode;
829 u32 spi_sr, spi_tcr;
830 u32 spi_tcnt, tcnt_diff;
831 int tx_word;
832
833 regmap_read(dspi->regmap, SPI_SR, &spi_sr);
834 regmap_write(dspi->regmap, SPI_SR, spi_sr);
835
836
837 if (spi_sr & (SPI_SR_EOQF | SPI_SR_TCFQF)) {
838 tx_word = is_double_byte_mode(dspi);
839
840 regmap_read(dspi->regmap, SPI_TCR, &spi_tcr);
841 spi_tcnt = SPI_TCR_GET_TCNT(spi_tcr);
842 /*
843 * The width of SPI Transfer Counter in SPI_TCR is 16bits,
844 * so the max couner is 65535. When the counter reach 65535,
845 * it will wrap around, counter reset to zero.
846 * spi_tcnt my be less than dspi->spi_tcnt, it means the
847 * counter already wrapped around.
848 * SPI Transfer Counter is a counter of transmitted frames.
849 * The size of frame maybe two bytes.
850 */
851 tcnt_diff = ((spi_tcnt + SPI_TCR_TCNT_MAX) - dspi->spi_tcnt)
852 % SPI_TCR_TCNT_MAX;
853 tcnt_diff *= (tx_word + 1);
854 if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM)
855 tcnt_diff--;
856
857 msg->actual_length += tcnt_diff;
858
859 dspi->spi_tcnt = spi_tcnt;
860
861 trans_mode = dspi->devtype_data->trans_mode;
862 switch (trans_mode) {
863 case DSPI_EOQ_MODE:
864 dspi_eoq_read(dspi);
865 break;
866 case DSPI_TCFQ_MODE:
867 dspi_tcfq_read(dspi);
868 break;
869 default:
870 dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
871 trans_mode);
872 return IRQ_HANDLED;
873 }
874
875 if (!dspi->len) {
876 if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM) {
877 regmap_update_bits(dspi->regmap,
878 SPI_CTAR(0),
879 SPI_FRAME_BITS_MASK,
880 SPI_FRAME_BITS(16));
881 dspi->dataflags &= ~TRAN_STATE_WORD_ODD_NUM;
882 }
883
884 dspi->waitflags = 1;
885 wake_up_interruptible(&dspi->waitq);
886 } else {
887 switch (trans_mode) {
888 case DSPI_EOQ_MODE:
889 dspi_eoq_write(dspi);
890 break;
891 case DSPI_TCFQ_MODE:
892 dspi_tcfq_write(dspi);
893 break;
894 default:
895 dev_err(&dspi->pdev->dev,
896 "unsupported trans_mode %u\n",
897 trans_mode);
898 }
899 }
900 }
901
902 return IRQ_HANDLED;
903 }
904
905 static const struct of_device_id fsl_dspi_dt_ids[] = {
906 { .compatible = "fsl,vf610-dspi", .data = &vf610_data, },
907 { .compatible = "fsl,ls1021a-v1.0-dspi", .data = &ls1021a_v1_data, },
908 { .compatible = "fsl,ls2085a-dspi", .data = &ls2085a_data, },
909 { /* sentinel */ }
910 };
911 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
912
913 #ifdef CONFIG_PM_SLEEP
914 static int dspi_suspend(struct device *dev)
915 {
916 struct spi_master *master = dev_get_drvdata(dev);
917 struct fsl_dspi *dspi = spi_master_get_devdata(master);
918
919 spi_master_suspend(master);
920 clk_disable_unprepare(dspi->clk);
921
922 pinctrl_pm_select_sleep_state(dev);
923
924 return 0;
925 }
926
927 static int dspi_resume(struct device *dev)
928 {
929 struct spi_master *master = dev_get_drvdata(dev);
930 struct fsl_dspi *dspi = spi_master_get_devdata(master);
931 int ret;
932
933 pinctrl_pm_select_default_state(dev);
934
935 ret = clk_prepare_enable(dspi->clk);
936 if (ret)
937 return ret;
938 spi_master_resume(master);
939
940 return 0;
941 }
942 #endif /* CONFIG_PM_SLEEP */
943
944 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
945
946 static const struct regmap_config dspi_regmap_config = {
947 .reg_bits = 32,
948 .val_bits = 32,
949 .reg_stride = 4,
950 .max_register = 0x88,
951 };
952
953 static void dspi_init(struct fsl_dspi *dspi)
954 {
955 regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
956 }
957
958 static int dspi_probe(struct platform_device *pdev)
959 {
960 struct device_node *np = pdev->dev.of_node;
961 struct spi_master *master;
962 struct fsl_dspi *dspi;
963 struct resource *res;
964 void __iomem *base;
965 struct fsl_dspi_platform_data *pdata;
966 int ret = 0, cs_num, bus_num;
967
968 master = spi_alloc_master(&pdev->dev, sizeof(struct fsl_dspi));
969 if (!master)
970 return -ENOMEM;
971
972 dspi = spi_master_get_devdata(master);
973 dspi->pdev = pdev;
974 dspi->master = master;
975
976 master->transfer = NULL;
977 master->setup = dspi_setup;
978 master->transfer_one_message = dspi_transfer_one_message;
979 master->dev.of_node = pdev->dev.of_node;
980
981 master->cleanup = dspi_cleanup;
982 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
983 master->bits_per_word_mask = SPI_BPW_MASK(4) | SPI_BPW_MASK(8) |
984 SPI_BPW_MASK(16);
985
986 pdata = dev_get_platdata(&pdev->dev);
987 if (pdata) {
988 master->num_chipselect = pdata->cs_num;
989 master->bus_num = pdata->bus_num;
990
991 dspi->devtype_data = &coldfire_data;
992 } else {
993
994 ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
995 if (ret < 0) {
996 dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
997 goto out_master_put;
998 }
999 master->num_chipselect = cs_num;
1000
1001 ret = of_property_read_u32(np, "bus-num", &bus_num);
1002 if (ret < 0) {
1003 dev_err(&pdev->dev, "can't get bus-num\n");
1004 goto out_master_put;
1005 }
1006 master->bus_num = bus_num;
1007
1008 dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1009 if (!dspi->devtype_data) {
1010 dev_err(&pdev->dev, "can't get devtype_data\n");
1011 ret = -EFAULT;
1012 goto out_master_put;
1013 }
1014 }
1015
1016 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1017 base = devm_ioremap_resource(&pdev->dev, res);
1018 if (IS_ERR(base)) {
1019 ret = PTR_ERR(base);
1020 goto out_master_put;
1021 }
1022
1023 dspi->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
1024 &dspi_regmap_config);
1025 if (IS_ERR(dspi->regmap)) {
1026 dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1027 PTR_ERR(dspi->regmap));
1028 ret = PTR_ERR(dspi->regmap);
1029 goto out_master_put;
1030 }
1031
1032 dspi_init(dspi);
1033 dspi->irq = platform_get_irq(pdev, 0);
1034 if (dspi->irq < 0) {
1035 dev_err(&pdev->dev, "can't get platform irq\n");
1036 ret = dspi->irq;
1037 goto out_master_put;
1038 }
1039
1040 ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt, 0,
1041 pdev->name, dspi);
1042 if (ret < 0) {
1043 dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1044 goto out_master_put;
1045 }
1046
1047 dspi->clk = devm_clk_get(&pdev->dev, "dspi");
1048 if (IS_ERR(dspi->clk)) {
1049 ret = PTR_ERR(dspi->clk);
1050 dev_err(&pdev->dev, "unable to get clock\n");
1051 goto out_master_put;
1052 }
1053 ret = clk_prepare_enable(dspi->clk);
1054 if (ret)
1055 goto out_master_put;
1056
1057 if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1058 ret = dspi_request_dma(dspi, res->start);
1059 if (ret < 0) {
1060 dev_err(&pdev->dev, "can't get dma channels\n");
1061 goto out_clk_put;
1062 }
1063 }
1064
1065 master->max_speed_hz =
1066 clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1067
1068 init_waitqueue_head(&dspi->waitq);
1069 platform_set_drvdata(pdev, master);
1070
1071 ret = spi_register_master(master);
1072 if (ret != 0) {
1073 dev_err(&pdev->dev, "Problem registering DSPI master\n");
1074 goto out_clk_put;
1075 }
1076
1077 return ret;
1078
1079 out_clk_put:
1080 clk_disable_unprepare(dspi->clk);
1081 out_master_put:
1082 spi_master_put(master);
1083
1084 return ret;
1085 }
1086
1087 static int dspi_remove(struct platform_device *pdev)
1088 {
1089 struct spi_master *master = platform_get_drvdata(pdev);
1090 struct fsl_dspi *dspi = spi_master_get_devdata(master);
1091
1092 /* Disconnect from the SPI framework */
1093 dspi_release_dma(dspi);
1094 clk_disable_unprepare(dspi->clk);
1095 spi_unregister_master(dspi->master);
1096
1097 return 0;
1098 }
1099
1100 static struct platform_driver fsl_dspi_driver = {
1101 .driver.name = DRIVER_NAME,
1102 .driver.of_match_table = fsl_dspi_dt_ids,
1103 .driver.owner = THIS_MODULE,
1104 .driver.pm = &dspi_pm,
1105 .probe = dspi_probe,
1106 .remove = dspi_remove,
1107 };
1108 module_platform_driver(fsl_dspi_driver);
1109
1110 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1111 MODULE_LICENSE("GPL");
1112 MODULE_ALIAS("platform:" DRIVER_NAME);
Linux with added FPC-III support