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1/*
2 * Freescale/Motorola Coldfire Queued SPI driver
3 *
4 * Copyright 2010 Steven King <sfking@fdwdc.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
19 *
20*/
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/interrupt.h>
25#include <linux/errno.h>
26#include <linux/platform_device.h>
27#include <linux/sched.h>
28#include <linux/workqueue.h>
29#include <linux/delay.h>
30#include <linux/io.h>
31#include <linux/clk.h>
32#include <linux/err.h>
33#include <linux/spi/spi.h>
34
35#include <asm/coldfire.h>
36#include <asm/mcfsim.h>
37#include <asm/mcfqspi.h>
38
39#define DRIVER_NAME "mcfqspi"
40
41#define MCFQSPI_BUSCLK (MCF_BUSCLK / 2)
42
43#define MCFQSPI_QMR 0x00
44#define MCFQSPI_QMR_MSTR 0x8000
45#define MCFQSPI_QMR_CPOL 0x0200
46#define MCFQSPI_QMR_CPHA 0x0100
47#define MCFQSPI_QDLYR 0x04
48#define MCFQSPI_QDLYR_SPE 0x8000
49#define MCFQSPI_QWR 0x08
50#define MCFQSPI_QWR_HALT 0x8000
51#define MCFQSPI_QWR_WREN 0x4000
52#define MCFQSPI_QWR_CSIV 0x1000
53#define MCFQSPI_QIR 0x0C
54#define MCFQSPI_QIR_WCEFB 0x8000
55#define MCFQSPI_QIR_ABRTB 0x4000
56#define MCFQSPI_QIR_ABRTL 0x1000
57#define MCFQSPI_QIR_WCEFE 0x0800
58#define MCFQSPI_QIR_ABRTE 0x0400
59#define MCFQSPI_QIR_SPIFE 0x0100
60#define MCFQSPI_QIR_WCEF 0x0008
61#define MCFQSPI_QIR_ABRT 0x0004
62#define MCFQSPI_QIR_SPIF 0x0001
63#define MCFQSPI_QAR 0x010
64#define MCFQSPI_QAR_TXBUF 0x00
65#define MCFQSPI_QAR_RXBUF 0x10
66#define MCFQSPI_QAR_CMDBUF 0x20
67#define MCFQSPI_QDR 0x014
68#define MCFQSPI_QCR 0x014
69#define MCFQSPI_QCR_CONT 0x8000
70#define MCFQSPI_QCR_BITSE 0x4000
71#define MCFQSPI_QCR_DT 0x2000
72
73struct mcfqspi {
74 void __iomem *iobase;
75 int irq;
76 struct clk *clk;
77 struct mcfqspi_cs_control *cs_control;
78
79 wait_queue_head_t waitq;
80
81 struct work_struct work;
82 struct workqueue_struct *workq;
83 spinlock_t lock;
84 struct list_head msgq;
85};
86
87static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
88{
89 writew(val, mcfqspi->iobase + MCFQSPI_QMR);
90}
91
92static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
93{
94 writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
95}
96
97static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
98{
99 return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
100}
101
102static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
103{
104 writew(val, mcfqspi->iobase + MCFQSPI_QWR);
105}
106
107static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
108{
109 writew(val, mcfqspi->iobase + MCFQSPI_QIR);
110}
111
112static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
113{
114 writew(val, mcfqspi->iobase + MCFQSPI_QAR);
115}
116
117static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
118{
119 writew(val, mcfqspi->iobase + MCFQSPI_QDR);
120}
121
122static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
123{
124 return readw(mcfqspi->iobase + MCFQSPI_QDR);
125}
126
127static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
128 bool cs_high)
129{
130 mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
131}
132
133static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
134 bool cs_high)
135{
136 mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
137}
138
139static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
140{
141 return (mcfqspi->cs_control && mcfqspi->cs_control->setup) ?
142 mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
143}
144
145static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
146{
147 if (mcfqspi->cs_control && mcfqspi->cs_control->teardown)
148 mcfqspi->cs_control->teardown(mcfqspi->cs_control);
149}
150
151static u8 mcfqspi_qmr_baud(u32 speed_hz)
152{
153 return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
154}
155
156static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
157{
158 return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
159}
160
161static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
162{
163 struct mcfqspi *mcfqspi = dev_id;
164
165 /* clear interrupt */
166 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
167 wake_up(&mcfqspi->waitq);
168
169 return IRQ_HANDLED;
170}
171
172static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
173 const u8 *txbuf, u8 *rxbuf)
174{
175 unsigned i, n, offset = 0;
176
177 n = min(count, 16u);
178
179 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
180 for (i = 0; i < n; ++i)
181 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
182
183 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
184 if (txbuf)
185 for (i = 0; i < n; ++i)
186 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
187 else
188 for (i = 0; i < count; ++i)
189 mcfqspi_wr_qdr(mcfqspi, 0);
190
191 count -= n;
192 if (count) {
193 u16 qwr = 0xf08;
194 mcfqspi_wr_qwr(mcfqspi, 0x700);
195 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
196
197 do {
198 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
199 mcfqspi_wr_qwr(mcfqspi, qwr);
200 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
201 if (rxbuf) {
202 mcfqspi_wr_qar(mcfqspi,
203 MCFQSPI_QAR_RXBUF + offset);
204 for (i = 0; i < 8; ++i)
205 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
206 }
207 n = min(count, 8u);
208 if (txbuf) {
209 mcfqspi_wr_qar(mcfqspi,
210 MCFQSPI_QAR_TXBUF + offset);
211 for (i = 0; i < n; ++i)
212 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
213 }
214 qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
215 offset ^= 8;
216 count -= n;
217 } while (count);
218 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
219 mcfqspi_wr_qwr(mcfqspi, qwr);
220 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
221 if (rxbuf) {
222 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
223 for (i = 0; i < 8; ++i)
224 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
225 offset ^= 8;
226 }
227 } else {
228 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
229 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
230 }
231 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
232 if (rxbuf) {
233 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
234 for (i = 0; i < n; ++i)
235 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
236 }
237}
238
239static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
240 const u16 *txbuf, u16 *rxbuf)
241{
242 unsigned i, n, offset = 0;
243
244 n = min(count, 16u);
245
246 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
247 for (i = 0; i < n; ++i)
248 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
249
250 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
251 if (txbuf)
252 for (i = 0; i < n; ++i)
253 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
254 else
255 for (i = 0; i < count; ++i)
256 mcfqspi_wr_qdr(mcfqspi, 0);
257
258 count -= n;
259 if (count) {
260 u16 qwr = 0xf08;
261 mcfqspi_wr_qwr(mcfqspi, 0x700);
262 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
263
264 do {
265 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
266 mcfqspi_wr_qwr(mcfqspi, qwr);
267 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
268 if (rxbuf) {
269 mcfqspi_wr_qar(mcfqspi,
270 MCFQSPI_QAR_RXBUF + offset);
271 for (i = 0; i < 8; ++i)
272 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
273 }
274 n = min(count, 8u);
275 if (txbuf) {
276 mcfqspi_wr_qar(mcfqspi,
277 MCFQSPI_QAR_TXBUF + offset);
278 for (i = 0; i < n; ++i)
279 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
280 }
281 qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
282 offset ^= 8;
283 count -= n;
284 } while (count);
285 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
286 mcfqspi_wr_qwr(mcfqspi, qwr);
287 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
288 if (rxbuf) {
289 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
290 for (i = 0; i < 8; ++i)
291 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
292 offset ^= 8;
293 }
294 } else {
295 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
296 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
297 }
298 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
299 if (rxbuf) {
300 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
301 for (i = 0; i < n; ++i)
302 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
303 }
304}
305
306static void mcfqspi_work(struct work_struct *work)
307{
308 struct mcfqspi *mcfqspi = container_of(work, struct mcfqspi, work);
309 unsigned long flags;
310
311 spin_lock_irqsave(&mcfqspi->lock, flags);
312 while (!list_empty(&mcfqspi->msgq)) {
313 struct spi_message *msg;
314 struct spi_device *spi;
315 struct spi_transfer *xfer;
316 int status = 0;
317
318 msg = container_of(mcfqspi->msgq.next, struct spi_message,
319 queue);
320
321 list_del_init(&msg->queue);
322 spin_unlock_irqrestore(&mcfqspi->lock, flags);
323
324 spi = msg->spi;
325
326 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
327 bool cs_high = spi->mode & SPI_CS_HIGH;
328 u16 qmr = MCFQSPI_QMR_MSTR;
329
330 if (xfer->bits_per_word)
331 qmr |= xfer->bits_per_word << 10;
332 else
333 qmr |= spi->bits_per_word << 10;
334 if (spi->mode & SPI_CPHA)
335 qmr |= MCFQSPI_QMR_CPHA;
336 if (spi->mode & SPI_CPOL)
337 qmr |= MCFQSPI_QMR_CPOL;
338 if (xfer->speed_hz)
339 qmr |= mcfqspi_qmr_baud(xfer->speed_hz);
340 else
341 qmr |= mcfqspi_qmr_baud(spi->max_speed_hz);
342 mcfqspi_wr_qmr(mcfqspi, qmr);
343
344 mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
345
346 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
347 if ((xfer->bits_per_word ? xfer->bits_per_word :
348 spi->bits_per_word) == 8)
349 mcfqspi_transfer_msg8(mcfqspi, xfer->len,
350 xfer->tx_buf,
351 xfer->rx_buf);
352 else
353 mcfqspi_transfer_msg16(mcfqspi, xfer->len / 2,
354 xfer->tx_buf,
355 xfer->rx_buf);
356 mcfqspi_wr_qir(mcfqspi, 0);
357
358 if (xfer->delay_usecs)
359 udelay(xfer->delay_usecs);
360 if (xfer->cs_change) {
361 if (!list_is_last(&xfer->transfer_list,
362 &msg->transfers))
363 mcfqspi_cs_deselect(mcfqspi,
364 spi->chip_select,
365 cs_high);
366 } else {
367 if (list_is_last(&xfer->transfer_list,
368 &msg->transfers))
369 mcfqspi_cs_deselect(mcfqspi,
370 spi->chip_select,
371 cs_high);
372 }
373 msg->actual_length += xfer->len;
374 }
375 msg->status = status;
376 msg->complete(msg->context);
377
378 spin_lock_irqsave(&mcfqspi->lock, flags);
379 }
380 spin_unlock_irqrestore(&mcfqspi->lock, flags);
381}
382
383static int mcfqspi_transfer(struct spi_device *spi, struct spi_message *msg)
384{
385 struct mcfqspi *mcfqspi;
386 struct spi_transfer *xfer;
387 unsigned long flags;
388
389 mcfqspi = spi_master_get_devdata(spi->master);
390
391 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
392 if (xfer->bits_per_word && ((xfer->bits_per_word < 8)
393 || (xfer->bits_per_word > 16))) {
394 dev_dbg(&spi->dev,
395 "%d bits per word is not supported\n",
396 xfer->bits_per_word);
397 goto fail;
398 }
399 if (xfer->speed_hz) {
400 u32 real_speed = MCFQSPI_BUSCLK /
401 mcfqspi_qmr_baud(xfer->speed_hz);
402 if (real_speed != xfer->speed_hz)
403 dev_dbg(&spi->dev,
404 "using speed %d instead of %d\n",
405 real_speed, xfer->speed_hz);
406 }
407 }
408 msg->status = -EINPROGRESS;
409 msg->actual_length = 0;
410
411 spin_lock_irqsave(&mcfqspi->lock, flags);
412 list_add_tail(&msg->queue, &mcfqspi->msgq);
413 queue_work(mcfqspi->workq, &mcfqspi->work);
414 spin_unlock_irqrestore(&mcfqspi->lock, flags);
415
416 return 0;
417fail:
418 msg->status = -EINVAL;
419 return -EINVAL;
420}
421
422static int mcfqspi_setup(struct spi_device *spi)
423{
424 if ((spi->bits_per_word < 8) || (spi->bits_per_word > 16)) {
425 dev_dbg(&spi->dev, "%d bits per word is not supported\n",
426 spi->bits_per_word);
427 return -EINVAL;
428 }
429 if (spi->chip_select >= spi->master->num_chipselect) {
430 dev_dbg(&spi->dev, "%d chip select is out of range\n",
431 spi->chip_select);
432 return -EINVAL;
433 }
434
435 mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
436 spi->chip_select, spi->mode & SPI_CS_HIGH);
437
438 dev_dbg(&spi->dev,
439 "bits per word %d, chip select %d, speed %d KHz\n",
440 spi->bits_per_word, spi->chip_select,
441 (MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
442 / 1000);
443
444 return 0;
445}
446
447static int __devinit mcfqspi_probe(struct platform_device *pdev)
448{
449 struct spi_master *master;
450 struct mcfqspi *mcfqspi;
451 struct resource *res;
452 struct mcfqspi_platform_data *pdata;
453 int status;
454
455 master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
456 if (master == NULL) {
457 dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
458 return -ENOMEM;
459 }
460
461 mcfqspi = spi_master_get_devdata(master);
462
463 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
464 if (!res) {
465 dev_dbg(&pdev->dev, "platform_get_resource failed\n");
466 status = -ENXIO;
467 goto fail0;
468 }
469
470 if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
471 dev_dbg(&pdev->dev, "request_mem_region failed\n");
472 status = -EBUSY;
473 goto fail0;
474 }
475
476 mcfqspi->iobase = ioremap(res->start, resource_size(res));
477 if (!mcfqspi->iobase) {
478 dev_dbg(&pdev->dev, "ioremap failed\n");
479 status = -ENOMEM;
480 goto fail1;
481 }
482
483 mcfqspi->irq = platform_get_irq(pdev, 0);
484 if (mcfqspi->irq < 0) {
485 dev_dbg(&pdev->dev, "platform_get_irq failed\n");
486 status = -ENXIO;
487 goto fail2;
488 }
489
490 status = request_irq(mcfqspi->irq, mcfqspi_irq_handler, IRQF_DISABLED,
491 pdev->name, mcfqspi);
492 if (status) {
493 dev_dbg(&pdev->dev, "request_irq failed\n");
494 goto fail2;
495 }
496
497 mcfqspi->clk = clk_get(&pdev->dev, "qspi_clk");
498 if (IS_ERR(mcfqspi->clk)) {
499 dev_dbg(&pdev->dev, "clk_get failed\n");
500 status = PTR_ERR(mcfqspi->clk);
501 goto fail3;
502 }
503 clk_enable(mcfqspi->clk);
504
505 mcfqspi->workq = create_singlethread_workqueue(dev_name(master->dev.parent));
506 if (!mcfqspi->workq) {
507 dev_dbg(&pdev->dev, "create_workqueue failed\n");
508 status = -ENOMEM;
509 goto fail4;
510 }
511 INIT_WORK(&mcfqspi->work, mcfqspi_work);
512 spin_lock_init(&mcfqspi->lock);
513 INIT_LIST_HEAD(&mcfqspi->msgq);
514 init_waitqueue_head(&mcfqspi->waitq);
515
516 pdata = pdev->dev.platform_data;
517 if (!pdata) {
518 dev_dbg(&pdev->dev, "platform data is missing\n");
519 goto fail5;
520 }
521 master->bus_num = pdata->bus_num;
522 master->num_chipselect = pdata->num_chipselect;
523
524 mcfqspi->cs_control = pdata->cs_control;
525 status = mcfqspi_cs_setup(mcfqspi);
526 if (status) {
527 dev_dbg(&pdev->dev, "error initializing cs_control\n");
528 goto fail5;
529 }
530
531 master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
532 master->setup = mcfqspi_setup;
533 master->transfer = mcfqspi_transfer;
534
535 platform_set_drvdata(pdev, master);
536
537 status = spi_register_master(master);
538 if (status) {
539 dev_dbg(&pdev->dev, "spi_register_master failed\n");
540 goto fail6;
541 }
542 dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
543
544 return 0;
545
546fail6:
547 mcfqspi_cs_teardown(mcfqspi);
548fail5:
549 destroy_workqueue(mcfqspi->workq);
550fail4:
551 clk_disable(mcfqspi->clk);
552 clk_put(mcfqspi->clk);
553fail3:
554 free_irq(mcfqspi->irq, mcfqspi);
555fail2:
556 iounmap(mcfqspi->iobase);
557fail1:
558 release_mem_region(res->start, resource_size(res));
559fail0:
560 spi_master_put(master);
561
562 dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
563
564 return status;
565}
566
567static int __devexit mcfqspi_remove(struct platform_device *pdev)
568{
569 struct spi_master *master = platform_get_drvdata(pdev);
570 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
571 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
572
573 /* disable the hardware (set the baud rate to 0) */
574 mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
575
576 platform_set_drvdata(pdev, NULL);
577 mcfqspi_cs_teardown(mcfqspi);
578 destroy_workqueue(mcfqspi->workq);
579 clk_disable(mcfqspi->clk);
580 clk_put(mcfqspi->clk);
581 free_irq(mcfqspi->irq, mcfqspi);
582 iounmap(mcfqspi->iobase);
583 release_mem_region(res->start, resource_size(res));
584 spi_unregister_master(master);
585 spi_master_put(master);
586
587 return 0;
588}
589
590#ifdef CONFIG_PM
591
592static int mcfqspi_suspend(struct device *dev)
593{
594 struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
595
596 clk_disable(mcfqspi->clk);
597
598 return 0;
599}
600
601static int mcfqspi_resume(struct device *dev)
602{
603 struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
604
605 clk_enable(mcfqspi->clk);
606
607 return 0;
608}
609
610static struct dev_pm_ops mcfqspi_dev_pm_ops = {
611 .suspend = mcfqspi_suspend,
612 .resume = mcfqspi_resume,
613};
614
615#define MCFQSPI_DEV_PM_OPS (&mcfqspi_dev_pm_ops)
616#else
617#define MCFQSPI_DEV_PM_OPS NULL
618#endif
619
620static struct platform_driver mcfqspi_driver = {
621 .driver.name = DRIVER_NAME,
622 .driver.owner = THIS_MODULE,
623 .driver.pm = MCFQSPI_DEV_PM_OPS,
624 .remove = __devexit_p(mcfqspi_remove),
625};
626
627static int __init mcfqspi_init(void)
628{
629 return platform_driver_probe(&mcfqspi_driver, mcfqspi_probe);
630}
631module_init(mcfqspi_init);
632
633static void __exit mcfqspi_exit(void)
634{
635 platform_driver_unregister(&mcfqspi_driver);
636}
637module_exit(mcfqspi_exit);
638
639MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
640MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
641MODULE_LICENSE("GPL");
642MODULE_ALIAS("platform:" DRIVER_NAME);
1/*
2 * Freescale/Motorola Coldfire Queued SPI driver
3 *
4 * Copyright 2010 Steven King <sfking@fdwdc.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15*/
16
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/interrupt.h>
20#include <linux/errno.h>
21#include <linux/platform_device.h>
22#include <linux/sched.h>
23#include <linux/delay.h>
24#include <linux/io.h>
25#include <linux/clk.h>
26#include <linux/err.h>
27#include <linux/spi/spi.h>
28#include <linux/pm_runtime.h>
29
30#include <asm/coldfire.h>
31#include <asm/mcfsim.h>
32#include <asm/mcfqspi.h>
33
34#define DRIVER_NAME "mcfqspi"
35
36#define MCFQSPI_BUSCLK (MCF_BUSCLK / 2)
37
38#define MCFQSPI_QMR 0x00
39#define MCFQSPI_QMR_MSTR 0x8000
40#define MCFQSPI_QMR_CPOL 0x0200
41#define MCFQSPI_QMR_CPHA 0x0100
42#define MCFQSPI_QDLYR 0x04
43#define MCFQSPI_QDLYR_SPE 0x8000
44#define MCFQSPI_QWR 0x08
45#define MCFQSPI_QWR_HALT 0x8000
46#define MCFQSPI_QWR_WREN 0x4000
47#define MCFQSPI_QWR_CSIV 0x1000
48#define MCFQSPI_QIR 0x0C
49#define MCFQSPI_QIR_WCEFB 0x8000
50#define MCFQSPI_QIR_ABRTB 0x4000
51#define MCFQSPI_QIR_ABRTL 0x1000
52#define MCFQSPI_QIR_WCEFE 0x0800
53#define MCFQSPI_QIR_ABRTE 0x0400
54#define MCFQSPI_QIR_SPIFE 0x0100
55#define MCFQSPI_QIR_WCEF 0x0008
56#define MCFQSPI_QIR_ABRT 0x0004
57#define MCFQSPI_QIR_SPIF 0x0001
58#define MCFQSPI_QAR 0x010
59#define MCFQSPI_QAR_TXBUF 0x00
60#define MCFQSPI_QAR_RXBUF 0x10
61#define MCFQSPI_QAR_CMDBUF 0x20
62#define MCFQSPI_QDR 0x014
63#define MCFQSPI_QCR 0x014
64#define MCFQSPI_QCR_CONT 0x8000
65#define MCFQSPI_QCR_BITSE 0x4000
66#define MCFQSPI_QCR_DT 0x2000
67
68struct mcfqspi {
69 void __iomem *iobase;
70 int irq;
71 struct clk *clk;
72 struct mcfqspi_cs_control *cs_control;
73
74 wait_queue_head_t waitq;
75};
76
77static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
78{
79 writew(val, mcfqspi->iobase + MCFQSPI_QMR);
80}
81
82static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
83{
84 writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
85}
86
87static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
88{
89 return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
90}
91
92static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
93{
94 writew(val, mcfqspi->iobase + MCFQSPI_QWR);
95}
96
97static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
98{
99 writew(val, mcfqspi->iobase + MCFQSPI_QIR);
100}
101
102static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
103{
104 writew(val, mcfqspi->iobase + MCFQSPI_QAR);
105}
106
107static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
108{
109 writew(val, mcfqspi->iobase + MCFQSPI_QDR);
110}
111
112static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
113{
114 return readw(mcfqspi->iobase + MCFQSPI_QDR);
115}
116
117static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
118 bool cs_high)
119{
120 mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
121}
122
123static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
124 bool cs_high)
125{
126 mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
127}
128
129static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
130{
131 return (mcfqspi->cs_control->setup) ?
132 mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
133}
134
135static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
136{
137 if (mcfqspi->cs_control->teardown)
138 mcfqspi->cs_control->teardown(mcfqspi->cs_control);
139}
140
141static u8 mcfqspi_qmr_baud(u32 speed_hz)
142{
143 return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
144}
145
146static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
147{
148 return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
149}
150
151static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
152{
153 struct mcfqspi *mcfqspi = dev_id;
154
155 /* clear interrupt */
156 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
157 wake_up(&mcfqspi->waitq);
158
159 return IRQ_HANDLED;
160}
161
162static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
163 const u8 *txbuf, u8 *rxbuf)
164{
165 unsigned i, n, offset = 0;
166
167 n = min(count, 16u);
168
169 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
170 for (i = 0; i < n; ++i)
171 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
172
173 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
174 if (txbuf)
175 for (i = 0; i < n; ++i)
176 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
177 else
178 for (i = 0; i < count; ++i)
179 mcfqspi_wr_qdr(mcfqspi, 0);
180
181 count -= n;
182 if (count) {
183 u16 qwr = 0xf08;
184 mcfqspi_wr_qwr(mcfqspi, 0x700);
185 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
186
187 do {
188 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
189 mcfqspi_wr_qwr(mcfqspi, qwr);
190 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
191 if (rxbuf) {
192 mcfqspi_wr_qar(mcfqspi,
193 MCFQSPI_QAR_RXBUF + offset);
194 for (i = 0; i < 8; ++i)
195 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
196 }
197 n = min(count, 8u);
198 if (txbuf) {
199 mcfqspi_wr_qar(mcfqspi,
200 MCFQSPI_QAR_TXBUF + offset);
201 for (i = 0; i < n; ++i)
202 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
203 }
204 qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
205 offset ^= 8;
206 count -= n;
207 } while (count);
208 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
209 mcfqspi_wr_qwr(mcfqspi, qwr);
210 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
211 if (rxbuf) {
212 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
213 for (i = 0; i < 8; ++i)
214 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
215 offset ^= 8;
216 }
217 } else {
218 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
219 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
220 }
221 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
222 if (rxbuf) {
223 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
224 for (i = 0; i < n; ++i)
225 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
226 }
227}
228
229static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
230 const u16 *txbuf, u16 *rxbuf)
231{
232 unsigned i, n, offset = 0;
233
234 n = min(count, 16u);
235
236 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
237 for (i = 0; i < n; ++i)
238 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
239
240 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
241 if (txbuf)
242 for (i = 0; i < n; ++i)
243 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
244 else
245 for (i = 0; i < count; ++i)
246 mcfqspi_wr_qdr(mcfqspi, 0);
247
248 count -= n;
249 if (count) {
250 u16 qwr = 0xf08;
251 mcfqspi_wr_qwr(mcfqspi, 0x700);
252 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
253
254 do {
255 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
256 mcfqspi_wr_qwr(mcfqspi, qwr);
257 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
258 if (rxbuf) {
259 mcfqspi_wr_qar(mcfqspi,
260 MCFQSPI_QAR_RXBUF + offset);
261 for (i = 0; i < 8; ++i)
262 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
263 }
264 n = min(count, 8u);
265 if (txbuf) {
266 mcfqspi_wr_qar(mcfqspi,
267 MCFQSPI_QAR_TXBUF + offset);
268 for (i = 0; i < n; ++i)
269 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
270 }
271 qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
272 offset ^= 8;
273 count -= n;
274 } while (count);
275 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
276 mcfqspi_wr_qwr(mcfqspi, qwr);
277 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
278 if (rxbuf) {
279 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
280 for (i = 0; i < 8; ++i)
281 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
282 offset ^= 8;
283 }
284 } else {
285 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
286 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
287 }
288 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
289 if (rxbuf) {
290 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
291 for (i = 0; i < n; ++i)
292 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
293 }
294}
295
296static void mcfqspi_set_cs(struct spi_device *spi, bool enable)
297{
298 struct mcfqspi *mcfqspi = spi_master_get_devdata(spi->master);
299 bool cs_high = spi->mode & SPI_CS_HIGH;
300
301 if (enable)
302 mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
303 else
304 mcfqspi_cs_deselect(mcfqspi, spi->chip_select, cs_high);
305}
306
307static int mcfqspi_transfer_one(struct spi_master *master,
308 struct spi_device *spi,
309 struct spi_transfer *t)
310{
311 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
312 u16 qmr = MCFQSPI_QMR_MSTR;
313
314 qmr |= t->bits_per_word << 10;
315 if (spi->mode & SPI_CPHA)
316 qmr |= MCFQSPI_QMR_CPHA;
317 if (spi->mode & SPI_CPOL)
318 qmr |= MCFQSPI_QMR_CPOL;
319 qmr |= mcfqspi_qmr_baud(t->speed_hz);
320 mcfqspi_wr_qmr(mcfqspi, qmr);
321
322 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
323 if (t->bits_per_word == 8)
324 mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf, t->rx_buf);
325 else
326 mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf,
327 t->rx_buf);
328 mcfqspi_wr_qir(mcfqspi, 0);
329
330 return 0;
331}
332
333static int mcfqspi_setup(struct spi_device *spi)
334{
335 mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
336 spi->chip_select, spi->mode & SPI_CS_HIGH);
337
338 dev_dbg(&spi->dev,
339 "bits per word %d, chip select %d, speed %d KHz\n",
340 spi->bits_per_word, spi->chip_select,
341 (MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
342 / 1000);
343
344 return 0;
345}
346
347static int mcfqspi_probe(struct platform_device *pdev)
348{
349 struct spi_master *master;
350 struct mcfqspi *mcfqspi;
351 struct resource *res;
352 struct mcfqspi_platform_data *pdata;
353 int status;
354
355 pdata = dev_get_platdata(&pdev->dev);
356 if (!pdata) {
357 dev_dbg(&pdev->dev, "platform data is missing\n");
358 return -ENOENT;
359 }
360
361 if (!pdata->cs_control) {
362 dev_dbg(&pdev->dev, "pdata->cs_control is NULL\n");
363 return -EINVAL;
364 }
365
366 master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
367 if (master == NULL) {
368 dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
369 return -ENOMEM;
370 }
371
372 mcfqspi = spi_master_get_devdata(master);
373
374 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
375 mcfqspi->iobase = devm_ioremap_resource(&pdev->dev, res);
376 if (IS_ERR(mcfqspi->iobase)) {
377 status = PTR_ERR(mcfqspi->iobase);
378 goto fail0;
379 }
380
381 mcfqspi->irq = platform_get_irq(pdev, 0);
382 if (mcfqspi->irq < 0) {
383 dev_dbg(&pdev->dev, "platform_get_irq failed\n");
384 status = -ENXIO;
385 goto fail0;
386 }
387
388 status = devm_request_irq(&pdev->dev, mcfqspi->irq, mcfqspi_irq_handler,
389 0, pdev->name, mcfqspi);
390 if (status) {
391 dev_dbg(&pdev->dev, "request_irq failed\n");
392 goto fail0;
393 }
394
395 mcfqspi->clk = devm_clk_get(&pdev->dev, "qspi_clk");
396 if (IS_ERR(mcfqspi->clk)) {
397 dev_dbg(&pdev->dev, "clk_get failed\n");
398 status = PTR_ERR(mcfqspi->clk);
399 goto fail0;
400 }
401 clk_enable(mcfqspi->clk);
402
403 master->bus_num = pdata->bus_num;
404 master->num_chipselect = pdata->num_chipselect;
405
406 mcfqspi->cs_control = pdata->cs_control;
407 status = mcfqspi_cs_setup(mcfqspi);
408 if (status) {
409 dev_dbg(&pdev->dev, "error initializing cs_control\n");
410 goto fail1;
411 }
412
413 init_waitqueue_head(&mcfqspi->waitq);
414
415 master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
416 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16);
417 master->setup = mcfqspi_setup;
418 master->set_cs = mcfqspi_set_cs;
419 master->transfer_one = mcfqspi_transfer_one;
420 master->auto_runtime_pm = true;
421
422 platform_set_drvdata(pdev, master);
423 pm_runtime_enable(&pdev->dev);
424
425 status = devm_spi_register_master(&pdev->dev, master);
426 if (status) {
427 dev_dbg(&pdev->dev, "spi_register_master failed\n");
428 goto fail2;
429 }
430
431 dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
432
433 return 0;
434
435fail2:
436 pm_runtime_disable(&pdev->dev);
437 mcfqspi_cs_teardown(mcfqspi);
438fail1:
439 clk_disable(mcfqspi->clk);
440fail0:
441 spi_master_put(master);
442
443 dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
444
445 return status;
446}
447
448static int mcfqspi_remove(struct platform_device *pdev)
449{
450 struct spi_master *master = platform_get_drvdata(pdev);
451 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
452
453 pm_runtime_disable(&pdev->dev);
454 /* disable the hardware (set the baud rate to 0) */
455 mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
456
457 mcfqspi_cs_teardown(mcfqspi);
458 clk_disable(mcfqspi->clk);
459
460 return 0;
461}
462
463#ifdef CONFIG_PM_SLEEP
464static int mcfqspi_suspend(struct device *dev)
465{
466 struct spi_master *master = dev_get_drvdata(dev);
467 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
468 int ret;
469
470 ret = spi_master_suspend(master);
471 if (ret)
472 return ret;
473
474 clk_disable(mcfqspi->clk);
475
476 return 0;
477}
478
479static int mcfqspi_resume(struct device *dev)
480{
481 struct spi_master *master = dev_get_drvdata(dev);
482 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
483
484 clk_enable(mcfqspi->clk);
485
486 return spi_master_resume(master);
487}
488#endif
489
490#ifdef CONFIG_PM
491static int mcfqspi_runtime_suspend(struct device *dev)
492{
493 struct spi_master *master = dev_get_drvdata(dev);
494 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
495
496 clk_disable(mcfqspi->clk);
497
498 return 0;
499}
500
501static int mcfqspi_runtime_resume(struct device *dev)
502{
503 struct spi_master *master = dev_get_drvdata(dev);
504 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
505
506 clk_enable(mcfqspi->clk);
507
508 return 0;
509}
510#endif
511
512static const struct dev_pm_ops mcfqspi_pm = {
513 SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume)
514 SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume,
515 NULL)
516};
517
518static struct platform_driver mcfqspi_driver = {
519 .driver.name = DRIVER_NAME,
520 .driver.owner = THIS_MODULE,
521 .driver.pm = &mcfqspi_pm,
522 .probe = mcfqspi_probe,
523 .remove = mcfqspi_remove,
524};
525module_platform_driver(mcfqspi_driver);
526
527MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
528MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
529MODULE_LICENSE("GPL");
530MODULE_ALIAS("platform:" DRIVER_NAME);