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/delay.h>
30 #include <linux/clk.h>
31 #include <linux/err.h>
32 #include <linux/spi/spi.h>
33 #include <linux/pm_runtime.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;
84 static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
86 writew(val, mcfqspi->iobase + MCFQSPI_QMR);
89 static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
91 writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
94 static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
96 return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
99 static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
101 writew(val, mcfqspi->iobase + MCFQSPI_QWR);
104 static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
106 writew(val, mcfqspi->iobase + MCFQSPI_QIR);
109 static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
111 writew(val, mcfqspi->iobase + MCFQSPI_QAR);
114 static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
116 writew(val, mcfqspi->iobase + MCFQSPI_QDR);
119 static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
121 return readw(mcfqspi->iobase + MCFQSPI_QDR);
124 static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
127 mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
130 static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
133 mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
136 static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
138 return (mcfqspi->cs_control && mcfqspi->cs_control->setup) ?
139 mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
142 static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
144 if (mcfqspi->cs_control && mcfqspi->cs_control->teardown)
145 mcfqspi->cs_control->teardown(mcfqspi->cs_control);
148 static u8 mcfqspi_qmr_baud(u32 speed_hz)
150 return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
153 static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
155 return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
158 static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
160 struct mcfqspi *mcfqspi = dev_id;
162 /* clear interrupt */
163 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
164 wake_up(&mcfqspi->waitq);
169 static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
170 const u8 *txbuf, u8 *rxbuf)
172 unsigned i, n, offset = 0;
176 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
177 for (i = 0; i < n; ++i)
178 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
180 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
182 for (i = 0; i < n; ++i)
183 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
185 for (i = 0; i < count; ++i)
186 mcfqspi_wr_qdr(mcfqspi, 0);
191 mcfqspi_wr_qwr(mcfqspi, 0x700);
192 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
195 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
196 mcfqspi_wr_qwr(mcfqspi, qwr);
197 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
199 mcfqspi_wr_qar(mcfqspi,
200 MCFQSPI_QAR_RXBUF + offset);
201 for (i = 0; i < 8; ++i)
202 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
206 mcfqspi_wr_qar(mcfqspi,
207 MCFQSPI_QAR_TXBUF + offset);
208 for (i = 0; i < n; ++i)
209 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
211 qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
215 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
216 mcfqspi_wr_qwr(mcfqspi, qwr);
217 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
219 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
220 for (i = 0; i < 8; ++i)
221 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
225 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
226 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
228 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
230 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
231 for (i = 0; i < n; ++i)
232 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
236 static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
237 const u16 *txbuf, u16 *rxbuf)
239 unsigned i, n, offset = 0;
243 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
244 for (i = 0; i < n; ++i)
245 mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
247 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
249 for (i = 0; i < n; ++i)
250 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
252 for (i = 0; i < count; ++i)
253 mcfqspi_wr_qdr(mcfqspi, 0);
258 mcfqspi_wr_qwr(mcfqspi, 0x700);
259 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
262 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
263 mcfqspi_wr_qwr(mcfqspi, qwr);
264 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
266 mcfqspi_wr_qar(mcfqspi,
267 MCFQSPI_QAR_RXBUF + offset);
268 for (i = 0; i < 8; ++i)
269 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
273 mcfqspi_wr_qar(mcfqspi,
274 MCFQSPI_QAR_TXBUF + offset);
275 for (i = 0; i < n; ++i)
276 mcfqspi_wr_qdr(mcfqspi, *txbuf++);
278 qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
282 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
283 mcfqspi_wr_qwr(mcfqspi, qwr);
284 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
286 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
287 for (i = 0; i < 8; ++i)
288 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
292 mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
293 mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
295 wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
297 mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
298 for (i = 0; i < n; ++i)
299 *rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
303 static int mcfqspi_transfer_one_message(struct spi_master *master,
304 struct spi_message *msg)
306 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
307 struct spi_device *spi = msg->spi;
308 struct spi_transfer *t;
311 list_for_each_entry(t, &msg->transfers, transfer_list) {
312 bool cs_high = spi->mode & SPI_CS_HIGH;
313 u16 qmr = MCFQSPI_QMR_MSTR;
315 if (t->bits_per_word)
316 qmr |= t->bits_per_word << 10;
318 qmr |= spi->bits_per_word << 10;
319 if (spi->mode & SPI_CPHA)
320 qmr |= MCFQSPI_QMR_CPHA;
321 if (spi->mode & SPI_CPOL)
322 qmr |= MCFQSPI_QMR_CPOL;
324 qmr |= mcfqspi_qmr_baud(t->speed_hz);
326 qmr |= mcfqspi_qmr_baud(spi->max_speed_hz);
327 mcfqspi_wr_qmr(mcfqspi, qmr);
329 mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
331 mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
332 if (t->bits_per_word == 8)
333 mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf,
336 mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf,
338 mcfqspi_wr_qir(mcfqspi, 0);
341 udelay(t->delay_usecs);
343 if (!list_is_last(&t->transfer_list, &msg->transfers))
344 mcfqspi_cs_deselect(mcfqspi, spi->chip_select,
347 if (list_is_last(&t->transfer_list, &msg->transfers))
348 mcfqspi_cs_deselect(mcfqspi, spi->chip_select,
351 msg->actual_length += t->len;
353 msg->status = status;
354 spi_finalize_current_message(master);
360 static int mcfqspi_prepare_transfer_hw(struct spi_master *master)
362 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
364 pm_runtime_get_sync(mcfqspi->dev);
369 static int mcfqspi_unprepare_transfer_hw(struct spi_master *master)
371 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
373 pm_runtime_put_sync(mcfqspi->dev);
378 static int mcfqspi_setup(struct spi_device *spi)
380 if ((spi->bits_per_word < 8) || (spi->bits_per_word > 16)) {
381 dev_dbg(&spi->dev, "%d bits per word is not supported\n",
385 if (spi->chip_select >= spi->master->num_chipselect) {
386 dev_dbg(&spi->dev, "%d chip select is out of range\n",
391 mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
392 spi->chip_select, spi->mode & SPI_CS_HIGH);
395 "bits per word %d, chip select %d, speed %d KHz\n",
396 spi->bits_per_word, spi->chip_select,
397 (MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
403 static int mcfqspi_probe(struct platform_device *pdev)
405 struct spi_master *master;
406 struct mcfqspi *mcfqspi;
407 struct resource *res;
408 struct mcfqspi_platform_data *pdata;
411 master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
412 if (master == NULL) {
413 dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
417 mcfqspi = spi_master_get_devdata(master);
419 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
421 dev_dbg(&pdev->dev, "platform_get_resource failed\n");
426 if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
427 dev_dbg(&pdev->dev, "request_mem_region failed\n");
432 mcfqspi->iobase = ioremap(res->start, resource_size(res));
433 if (!mcfqspi->iobase) {
434 dev_dbg(&pdev->dev, "ioremap failed\n");
439 mcfqspi->irq = platform_get_irq(pdev, 0);
440 if (mcfqspi->irq < 0) {
441 dev_dbg(&pdev->dev, "platform_get_irq failed\n");
446 status = request_irq(mcfqspi->irq, mcfqspi_irq_handler, 0,
447 pdev->name, mcfqspi);
449 dev_dbg(&pdev->dev, "request_irq failed\n");
453 mcfqspi->clk = clk_get(&pdev->dev, "qspi_clk");
454 if (IS_ERR(mcfqspi->clk)) {
455 dev_dbg(&pdev->dev, "clk_get failed\n");
456 status = PTR_ERR(mcfqspi->clk);
459 clk_enable(mcfqspi->clk);
461 pdata = pdev->dev.platform_data;
463 dev_dbg(&pdev->dev, "platform data is missing\n");
466 master->bus_num = pdata->bus_num;
467 master->num_chipselect = pdata->num_chipselect;
469 mcfqspi->cs_control = pdata->cs_control;
470 status = mcfqspi_cs_setup(mcfqspi);
472 dev_dbg(&pdev->dev, "error initializing cs_control\n");
476 init_waitqueue_head(&mcfqspi->waitq);
477 mcfqspi->dev = &pdev->dev;
479 master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
480 master->setup = mcfqspi_setup;
481 master->transfer_one_message = mcfqspi_transfer_one_message;
482 master->prepare_transfer_hardware = mcfqspi_prepare_transfer_hw;
483 master->unprepare_transfer_hardware = mcfqspi_unprepare_transfer_hw;
485 platform_set_drvdata(pdev, master);
487 status = spi_register_master(master);
489 dev_dbg(&pdev->dev, "spi_register_master failed\n");
492 pm_runtime_enable(mcfqspi->dev);
494 dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
499 mcfqspi_cs_teardown(mcfqspi);
501 clk_disable(mcfqspi->clk);
502 clk_put(mcfqspi->clk);
504 free_irq(mcfqspi->irq, mcfqspi);
506 iounmap(mcfqspi->iobase);
508 release_mem_region(res->start, resource_size(res));
510 spi_master_put(master);
512 dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
517 static int mcfqspi_remove(struct platform_device *pdev)
519 struct spi_master *master = platform_get_drvdata(pdev);
520 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
521 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
523 pm_runtime_disable(mcfqspi->dev);
524 /* disable the hardware (set the baud rate to 0) */
525 mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
527 platform_set_drvdata(pdev, NULL);
528 mcfqspi_cs_teardown(mcfqspi);
529 clk_disable(mcfqspi->clk);
530 clk_put(mcfqspi->clk);
531 free_irq(mcfqspi->irq, mcfqspi);
532 iounmap(mcfqspi->iobase);
533 release_mem_region(res->start, resource_size(res));
534 spi_unregister_master(master);
539 #ifdef CONFIG_PM_SLEEP
540 static int mcfqspi_suspend(struct device *dev)
542 struct spi_master *master = dev_get_drvdata(dev);
543 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
545 spi_master_suspend(master);
547 clk_disable(mcfqspi->clk);
552 static int mcfqspi_resume(struct device *dev)
554 struct spi_master *master = dev_get_drvdata(dev);
555 struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
557 spi_master_resume(master);
559 clk_enable(mcfqspi->clk);
565 #ifdef CONFIG_PM_RUNTIME
566 static int mcfqspi_runtime_suspend(struct device *dev)
568 struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
570 clk_disable(mcfqspi->clk);
575 static int mcfqspi_runtime_resume(struct device *dev)
577 struct mcfqspi *mcfqspi = platform_get_drvdata(to_platform_device(dev));
579 clk_enable(mcfqspi->clk);
585 static const struct dev_pm_ops mcfqspi_pm = {
586 SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume)
587 SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume,
591 static struct platform_driver mcfqspi_driver = {
592 .driver.name = DRIVER_NAME,
593 .driver.owner = THIS_MODULE,
594 .driver.pm = &mcfqspi_pm,
595 .probe = mcfqspi_probe,
596 .remove = mcfqspi_remove,
598 module_platform_driver(mcfqspi_driver);
600 MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
601 MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
602 MODULE_LICENSE("GPL");
603 MODULE_ALIAS("platform:" DRIVER_NAME);