2 * Freescale/Motorola Coldfire Queued SPI driver
4 * Copyright 2010 Steven King <sfking@fdwdc.com>
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.
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.
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
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>
31 #include <linux/clk.h>
32 #include <linux/err.h>
33 #include <linux/spi/spi.h>
35 #include <asm/coldfire.h>
36 #include <asm/mcfsim.h>
37 #include <asm/mcfqspi.h>
39 #define DRIVER_NAME "mcfqspi"
41 #define MCFQSPI_BUSCLK (MCF_BUSCLK / 2)
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
77 struct mcfqspi_cs_control *cs_control;
79 wait_queue_head_t waitq;
81 struct work_struct work;
82 struct workqueue_struct *workq;
84 struct list_head msgq;
87 static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
89 writew(val, mcfqspi->iobase + MCFQSPI_QMR);
92 static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
94 writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
97 static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
99 return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
102 static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
104 writew(val, mcfqspi->iobase + MCFQSPI_QWR);
107 static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
109 writew(val, mcfqspi->iobase + MCFQSPI_QIR);
112 static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
114 writew(val, mcfqspi->iobase + MCFQSPI_QAR);
117 static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
119 writew(val, mcfqspi->iobase + MCFQSPI_QDR);
122 static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
124 return readw(mcfqspi->iobase + MCFQSPI_QDR);
127 static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
130 mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
133 static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
136 mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
139 static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
141 return (mcfqspi->cs_control && mcfqspi->cs_control->setup) ?
142 mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
145 static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
147 if (mcfqspi->cs_control && mcfqspi->cs_control->teardown)
148 mcfqspi->cs_control->teardown(mcfqspi->cs_control);
151 static u8 mcfqspi_qmr_baud(u32 speed_hz)
153 return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
156 static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
158 return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
161 static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
163 struct mcfqspi *mcfqspi = dev_id;
165 /* clear interrupt */
166 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
167 wake_up(&mcfqspi->waitq);
172 static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
173 const u8 *txbuf, u8 *rxbuf)
175 unsigned i, n, offset = 0;
179 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
180 for (i = 0; i < n; ++i)
181 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
183 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
185 for (i = 0; i < n; ++i)
186 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
188 for (i = 0; i < count; ++i)
189 mcfqspi_wr_qdr(mcfqspi, 0);
194 mcfqspi_wr_qwr(mcfqspi, 0x700);
195 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
198 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
199 mcfqspi_wr_qwr(mcfqspi, qwr);
200 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
202 mcfqspi_wr_qar(mcfqspi,
203 MCFQSPI_QAR_RXBUF + offset);
204 for (i = 0; i < 8; ++i)
205 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
209 mcfqspi_wr_qar(mcfqspi,
210 MCFQSPI_QAR_TXBUF + offset);
211 for (i = 0; i < n; ++i)
212 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
214 qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
218 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
219 mcfqspi_wr_qwr(mcfqspi, qwr);
220 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
222 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
223 for (i = 0; i < 8; ++i)
224 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
228 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
229 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
231 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
233 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
234 for (i = 0; i < n; ++i)
235 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
239 static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
240 const u16 *txbuf, u16 *rxbuf)
242 unsigned i, n, offset = 0;
246 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
247 for (i = 0; i < n; ++i)
248 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
250 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
252 for (i = 0; i < n; ++i)
253 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
255 for (i = 0; i < count; ++i)
256 mcfqspi_wr_qdr(mcfqspi, 0);
261 mcfqspi_wr_qwr(mcfqspi, 0x700);
262 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
265 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
266 mcfqspi_wr_qwr(mcfqspi, qwr);
267 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
269 mcfqspi_wr_qar(mcfqspi,
270 MCFQSPI_QAR_RXBUF + offset);
271 for (i = 0; i < 8; ++i)
272 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
276 mcfqspi_wr_qar(mcfqspi,
277 MCFQSPI_QAR_TXBUF + offset);
278 for (i = 0; i < n; ++i)
279 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
281 qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
285 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
286 mcfqspi_wr_qwr(mcfqspi, qwr);
287 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
289 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
290 for (i = 0; i < 8; ++i)
291 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
295 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
296 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
298 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
300 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
301 for (i = 0; i < n; ++i)
302 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
306 static void mcfqspi_work(struct work_struct *work)
308 struct mcfqspi *mcfqspi = container_of(work, struct mcfqspi, work);
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;
318 msg = container_of(mcfqspi->msgq.next, struct spi_message,
321 list_del_init(&msg->queue);
322 spin_unlock_irqrestore(&mcfqspi->lock, flags);
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;
330 if (xfer->bits_per_word)
331 qmr |= xfer->bits_per_word << 10;
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;
339 qmr |= mcfqspi_qmr_baud(xfer->speed_hz);
341 qmr |= mcfqspi_qmr_baud(spi->max_speed_hz);
342 mcfqspi_wr_qmr(mcfqspi, qmr);
344 mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
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,
353 mcfqspi_transfer_msg16(mcfqspi, xfer->len / 2,
356 mcfqspi_wr_qir(mcfqspi, 0);
358 if (xfer->delay_usecs)
359 udelay(xfer->delay_usecs);
360 if (xfer->cs_change) {
361 if (!list_is_last(&xfer->transfer_list,
363 mcfqspi_cs_deselect(mcfqspi,
367 if (list_is_last(&xfer->transfer_list,
369 mcfqspi_cs_deselect(mcfqspi,
373 msg->actual_length += xfer->len;
375 msg->status = status;
376 msg->complete(msg->context);
378 spin_lock_irqsave(&mcfqspi->lock, flags);
380 spin_unlock_irqrestore(&mcfqspi->lock, flags);
383 static int mcfqspi_transfer(struct spi_device *spi, struct spi_message *msg)
385 struct mcfqspi *mcfqspi;
386 struct spi_transfer *xfer;
389 mcfqspi = spi_master_get_devdata(spi->master);
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))) {
395 "%d bits per word is not supported\n",
396 xfer->bits_per_word);
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)
404 "using speed %d instead of %d\n",
405 real_speed, xfer->speed_hz);
408 msg->status = -EINPROGRESS;
409 msg->actual_length = 0;
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);
418 msg->status = -EINVAL;
422 static int mcfqspi_setup(struct spi_device *spi)
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",
429 if (spi->chip_select >= spi->master->num_chipselect) {
430 dev_dbg(&spi->dev, "%d chip select is out of range\n",
435 mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
436 spi->chip_select, spi->mode & SPI_CS_HIGH);
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))
447 static int __devinit mcfqspi_probe(struct platform_device *pdev)
449 struct spi_master *master;
450 struct mcfqspi *mcfqspi;
451 struct resource *res;
452 struct mcfqspi_platform_data *pdata;
455 master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
456 if (master == NULL) {
457 dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
461 mcfqspi = spi_master_get_devdata(master);
463 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
465 dev_dbg(&pdev->dev, "platform_get_resource failed\n");
470 if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
471 dev_dbg(&pdev->dev, "request_mem_region failed\n");
476 mcfqspi->iobase = ioremap(res->start, resource_size(res));
477 if (!mcfqspi->iobase) {
478 dev_dbg(&pdev->dev, "ioremap failed\n");
483 mcfqspi->irq = platform_get_irq(pdev, 0);
484 if (mcfqspi->irq < 0) {
485 dev_dbg(&pdev->dev, "platform_get_irq failed\n");
490 status = request_irq(mcfqspi->irq, mcfqspi_irq_handler, IRQF_DISABLED,
491 pdev->name, mcfqspi);
493 dev_dbg(&pdev->dev, "request_irq failed\n");
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);
503 clk_enable(mcfqspi->clk);
505 mcfqspi->workq = create_singlethread_workqueue(dev_name(master->dev.parent));
506 if (!mcfqspi->workq) {
507 dev_dbg(&pdev->dev, "create_workqueue failed\n");
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);
516 pdata = pdev->dev.platform_data;
518 dev_dbg(&pdev->dev, "platform data is missing\n");
521 master->bus_num = pdata->bus_num;
522 master->num_chipselect = pdata->num_chipselect;
524 mcfqspi->cs_control = pdata->cs_control;
525 status = mcfqspi_cs_setup(mcfqspi);
527 dev_dbg(&pdev->dev, "error initializing cs_control\n");
531 master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
532 master->setup = mcfqspi_setup;
533 master->transfer = mcfqspi_transfer;
535 platform_set_drvdata(pdev, master);
537 status = spi_register_master(master);
539 dev_dbg(&pdev->dev, "spi_register_master failed\n");
542 dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
547 mcfqspi_cs_teardown(mcfqspi);
549 destroy_workqueue(mcfqspi->workq);
551 clk_disable(mcfqspi->clk);
552 clk_put(mcfqspi->clk);
554 free_irq(mcfqspi->irq, mcfqspi);
556 iounmap(mcfqspi->iobase);
558 release_mem_region(res->start, resource_size(res));
560 spi_master_put(master);
562 dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
567 static int __devexit mcfqspi_remove(struct platform_device *pdev)
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);
573 /* disable the hardware (set the baud rate to 0) */
574 mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
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);
592 static int mcfqspi_suspend(struct device *dev)
594 struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
596 clk_disable(mcfqspi->clk);
601 static int mcfqspi_resume(struct device *dev)
603 struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
605 clk_enable(mcfqspi->clk);
610 static struct dev_pm_ops mcfqspi_dev_pm_ops = {
611 .suspend = mcfqspi_suspend,
612 .resume = mcfqspi_resume,
615 #define MCFQSPI_DEV_PM_OPS (&mcfqspi_dev_pm_ops)
617 #define MCFQSPI_DEV_PM_OPS NULL
620 static 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),
627 static int __init mcfqspi_init(void)
629 return platform_driver_probe(&mcfqspi_driver, mcfqspi_probe);
631 module_init(mcfqspi_init);
633 static void __exit mcfqspi_exit(void)
635 platform_driver_unregister(&mcfqspi_driver);
637 module_exit(mcfqspi_exit);
639 MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
640 MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
641 MODULE_LICENSE("GPL");
642 MODULE_ALIAS("platform:" DRIVER_NAME);