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v6.2
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Freescale/Motorola Coldfire Queued SPI driver
  4 *
  5 * Copyright 2010 Steven King <sfking@fdwdc.com>
 
 
 
 
 
 
 
 
 
 
  6*/
  7
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/interrupt.h>
 11#include <linux/errno.h>
 12#include <linux/platform_device.h>
 13#include <linux/sched.h>
 14#include <linux/delay.h>
 15#include <linux/io.h>
 16#include <linux/clk.h>
 17#include <linux/err.h>
 18#include <linux/spi/spi.h>
 19#include <linux/pm_runtime.h>
 20
 21#include <asm/coldfire.h>
 22#include <asm/mcfsim.h>
 23#include <asm/mcfqspi.h>
 24
 25#define	DRIVER_NAME "mcfqspi"
 26
 27#define	MCFQSPI_BUSCLK			(MCF_BUSCLK / 2)
 28
 29#define	MCFQSPI_QMR			0x00
 30#define		MCFQSPI_QMR_MSTR	0x8000
 31#define		MCFQSPI_QMR_CPOL	0x0200
 32#define		MCFQSPI_QMR_CPHA	0x0100
 33#define	MCFQSPI_QDLYR			0x04
 34#define		MCFQSPI_QDLYR_SPE	0x8000
 35#define	MCFQSPI_QWR			0x08
 36#define		MCFQSPI_QWR_HALT	0x8000
 37#define		MCFQSPI_QWR_WREN	0x4000
 38#define		MCFQSPI_QWR_CSIV	0x1000
 39#define	MCFQSPI_QIR			0x0C
 40#define		MCFQSPI_QIR_WCEFB	0x8000
 41#define		MCFQSPI_QIR_ABRTB	0x4000
 42#define		MCFQSPI_QIR_ABRTL	0x1000
 43#define		MCFQSPI_QIR_WCEFE	0x0800
 44#define		MCFQSPI_QIR_ABRTE	0x0400
 45#define		MCFQSPI_QIR_SPIFE	0x0100
 46#define		MCFQSPI_QIR_WCEF	0x0008
 47#define		MCFQSPI_QIR_ABRT	0x0004
 48#define		MCFQSPI_QIR_SPIF	0x0001
 49#define	MCFQSPI_QAR			0x010
 50#define		MCFQSPI_QAR_TXBUF	0x00
 51#define		MCFQSPI_QAR_RXBUF	0x10
 52#define		MCFQSPI_QAR_CMDBUF	0x20
 53#define	MCFQSPI_QDR			0x014
 54#define	MCFQSPI_QCR			0x014
 55#define		MCFQSPI_QCR_CONT	0x8000
 56#define		MCFQSPI_QCR_BITSE	0x4000
 57#define		MCFQSPI_QCR_DT		0x2000
 58
 59struct mcfqspi {
 60	void __iomem *iobase;
 61	int irq;
 62	struct clk *clk;
 63	struct mcfqspi_cs_control *cs_control;
 64
 65	wait_queue_head_t waitq;
 66};
 67
 68static void mcfqspi_wr_qmr(struct mcfqspi *mcfqspi, u16 val)
 69{
 70	writew(val, mcfqspi->iobase + MCFQSPI_QMR);
 71}
 72
 73static void mcfqspi_wr_qdlyr(struct mcfqspi *mcfqspi, u16 val)
 74{
 75	writew(val, mcfqspi->iobase + MCFQSPI_QDLYR);
 76}
 77
 78static u16 mcfqspi_rd_qdlyr(struct mcfqspi *mcfqspi)
 79{
 80	return readw(mcfqspi->iobase + MCFQSPI_QDLYR);
 81}
 82
 83static void mcfqspi_wr_qwr(struct mcfqspi *mcfqspi, u16 val)
 84{
 85	writew(val, mcfqspi->iobase + MCFQSPI_QWR);
 86}
 87
 88static void mcfqspi_wr_qir(struct mcfqspi *mcfqspi, u16 val)
 89{
 90	writew(val, mcfqspi->iobase + MCFQSPI_QIR);
 91}
 92
 93static void mcfqspi_wr_qar(struct mcfqspi *mcfqspi, u16 val)
 94{
 95	writew(val, mcfqspi->iobase + MCFQSPI_QAR);
 96}
 97
 98static void mcfqspi_wr_qdr(struct mcfqspi *mcfqspi, u16 val)
 99{
100	writew(val, mcfqspi->iobase + MCFQSPI_QDR);
101}
102
103static u16 mcfqspi_rd_qdr(struct mcfqspi *mcfqspi)
104{
105	return readw(mcfqspi->iobase + MCFQSPI_QDR);
106}
107
108static void mcfqspi_cs_select(struct mcfqspi *mcfqspi, u8 chip_select,
109			    bool cs_high)
110{
111	mcfqspi->cs_control->select(mcfqspi->cs_control, chip_select, cs_high);
112}
113
114static void mcfqspi_cs_deselect(struct mcfqspi *mcfqspi, u8 chip_select,
115				bool cs_high)
116{
117	mcfqspi->cs_control->deselect(mcfqspi->cs_control, chip_select, cs_high);
118}
119
120static int mcfqspi_cs_setup(struct mcfqspi *mcfqspi)
121{
122	return (mcfqspi->cs_control->setup) ?
123		mcfqspi->cs_control->setup(mcfqspi->cs_control) : 0;
124}
125
126static void mcfqspi_cs_teardown(struct mcfqspi *mcfqspi)
127{
128	if (mcfqspi->cs_control->teardown)
129		mcfqspi->cs_control->teardown(mcfqspi->cs_control);
130}
131
132static u8 mcfqspi_qmr_baud(u32 speed_hz)
133{
134	return clamp((MCFQSPI_BUSCLK + speed_hz - 1) / speed_hz, 2u, 255u);
135}
136
137static bool mcfqspi_qdlyr_spe(struct mcfqspi *mcfqspi)
138{
139	return mcfqspi_rd_qdlyr(mcfqspi) & MCFQSPI_QDLYR_SPE;
140}
141
142static irqreturn_t mcfqspi_irq_handler(int this_irq, void *dev_id)
143{
144	struct mcfqspi *mcfqspi = dev_id;
145
146	/* clear interrupt */
147	mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE | MCFQSPI_QIR_SPIF);
148	wake_up(&mcfqspi->waitq);
149
150	return IRQ_HANDLED;
151}
152
153static void mcfqspi_transfer_msg8(struct mcfqspi *mcfqspi, unsigned count,
154				  const u8 *txbuf, u8 *rxbuf)
155{
156	unsigned i, n, offset = 0;
157
158	n = min(count, 16u);
159
160	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
161	for (i = 0; i < n; ++i)
162		mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
163
164	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
165	if (txbuf)
166		for (i = 0; i < n; ++i)
167			mcfqspi_wr_qdr(mcfqspi, *txbuf++);
168	else
169		for (i = 0; i < count; ++i)
170			mcfqspi_wr_qdr(mcfqspi, 0);
171
172	count -= n;
173	if (count) {
174		u16 qwr = 0xf08;
175		mcfqspi_wr_qwr(mcfqspi, 0x700);
176		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
177
178		do {
179			wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
180			mcfqspi_wr_qwr(mcfqspi, qwr);
181			mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
182			if (rxbuf) {
183				mcfqspi_wr_qar(mcfqspi,
184					       MCFQSPI_QAR_RXBUF + offset);
185				for (i = 0; i < 8; ++i)
186					*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
187			}
188			n = min(count, 8u);
189			if (txbuf) {
190				mcfqspi_wr_qar(mcfqspi,
191					       MCFQSPI_QAR_TXBUF + offset);
192				for (i = 0; i < n; ++i)
193					mcfqspi_wr_qdr(mcfqspi, *txbuf++);
194			}
195			qwr = (offset ? 0x808 : 0) + ((n - 1) << 8);
196			offset ^= 8;
197			count -= n;
198		} while (count);
199		wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
200		mcfqspi_wr_qwr(mcfqspi, qwr);
201		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
202		if (rxbuf) {
203			mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
204			for (i = 0; i < 8; ++i)
205				*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
206			offset ^= 8;
207		}
208	} else {
209		mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
210		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
211	}
212	wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
213	if (rxbuf) {
214		mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
215		for (i = 0; i < n; ++i)
216			*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
217	}
218}
219
220static void mcfqspi_transfer_msg16(struct mcfqspi *mcfqspi, unsigned count,
221				   const u16 *txbuf, u16 *rxbuf)
222{
223	unsigned i, n, offset = 0;
224
225	n = min(count, 16u);
226
227	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_CMDBUF);
228	for (i = 0; i < n; ++i)
229		mcfqspi_wr_qdr(mcfqspi, MCFQSPI_QCR_BITSE);
230
231	mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_TXBUF);
232	if (txbuf)
233		for (i = 0; i < n; ++i)
234			mcfqspi_wr_qdr(mcfqspi, *txbuf++);
235	else
236		for (i = 0; i < count; ++i)
237			mcfqspi_wr_qdr(mcfqspi, 0);
238
239	count -= n;
240	if (count) {
241		u16 qwr = 0xf08;
242		mcfqspi_wr_qwr(mcfqspi, 0x700);
243		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
244
245		do {
246			wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
247			mcfqspi_wr_qwr(mcfqspi, qwr);
248			mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
249			if (rxbuf) {
250				mcfqspi_wr_qar(mcfqspi,
251					       MCFQSPI_QAR_RXBUF + offset);
252				for (i = 0; i < 8; ++i)
253					*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
254			}
255			n = min(count, 8u);
256			if (txbuf) {
257				mcfqspi_wr_qar(mcfqspi,
258					       MCFQSPI_QAR_TXBUF + offset);
259				for (i = 0; i < n; ++i)
260					mcfqspi_wr_qdr(mcfqspi, *txbuf++);
261			}
262			qwr = (offset ? 0x808 : 0x000) + ((n - 1) << 8);
263			offset ^= 8;
264			count -= n;
265		} while (count);
266		wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
267		mcfqspi_wr_qwr(mcfqspi, qwr);
268		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
269		if (rxbuf) {
270			mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
271			for (i = 0; i < 8; ++i)
272				*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
273			offset ^= 8;
274		}
275	} else {
276		mcfqspi_wr_qwr(mcfqspi, (n - 1) << 8);
277		mcfqspi_wr_qdlyr(mcfqspi, MCFQSPI_QDLYR_SPE);
278	}
279	wait_event(mcfqspi->waitq, !mcfqspi_qdlyr_spe(mcfqspi));
280	if (rxbuf) {
281		mcfqspi_wr_qar(mcfqspi, MCFQSPI_QAR_RXBUF + offset);
282		for (i = 0; i < n; ++i)
283			*rxbuf++ = mcfqspi_rd_qdr(mcfqspi);
284	}
285}
286
287static void mcfqspi_set_cs(struct spi_device *spi, bool enable)
288{
289	struct mcfqspi *mcfqspi = spi_master_get_devdata(spi->master);
290	bool cs_high = spi->mode & SPI_CS_HIGH;
291
292	if (enable)
293		mcfqspi_cs_select(mcfqspi, spi->chip_select, cs_high);
294	else
295		mcfqspi_cs_deselect(mcfqspi, spi->chip_select, cs_high);
296}
297
298static int mcfqspi_transfer_one(struct spi_master *master,
299				struct spi_device *spi,
300				struct spi_transfer *t)
301{
302	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
303	u16 qmr = MCFQSPI_QMR_MSTR;
304
305	qmr |= t->bits_per_word << 10;
306	if (spi->mode & SPI_CPHA)
307		qmr |= MCFQSPI_QMR_CPHA;
308	if (spi->mode & SPI_CPOL)
309		qmr |= MCFQSPI_QMR_CPOL;
310	qmr |= mcfqspi_qmr_baud(t->speed_hz);
311	mcfqspi_wr_qmr(mcfqspi, qmr);
312
313	mcfqspi_wr_qir(mcfqspi, MCFQSPI_QIR_SPIFE);
314	if (t->bits_per_word == 8)
315		mcfqspi_transfer_msg8(mcfqspi, t->len, t->tx_buf, t->rx_buf);
316	else
317		mcfqspi_transfer_msg16(mcfqspi, t->len / 2, t->tx_buf,
318				       t->rx_buf);
319	mcfqspi_wr_qir(mcfqspi, 0);
320
321	return 0;
322}
323
324static int mcfqspi_setup(struct spi_device *spi)
325{
326	mcfqspi_cs_deselect(spi_master_get_devdata(spi->master),
327			    spi->chip_select, spi->mode & SPI_CS_HIGH);
328
329	dev_dbg(&spi->dev,
330			"bits per word %d, chip select %d, speed %d KHz\n",
331			spi->bits_per_word, spi->chip_select,
332			(MCFQSPI_BUSCLK / mcfqspi_qmr_baud(spi->max_speed_hz))
333			/ 1000);
334
335	return 0;
336}
337
338static int mcfqspi_probe(struct platform_device *pdev)
339{
340	struct spi_master *master;
341	struct mcfqspi *mcfqspi;
 
342	struct mcfqspi_platform_data *pdata;
343	int status;
344
345	pdata = dev_get_platdata(&pdev->dev);
346	if (!pdata) {
347		dev_dbg(&pdev->dev, "platform data is missing\n");
348		return -ENOENT;
349	}
350
351	if (!pdata->cs_control) {
352		dev_dbg(&pdev->dev, "pdata->cs_control is NULL\n");
353		return -EINVAL;
354	}
355
356	master = spi_alloc_master(&pdev->dev, sizeof(*mcfqspi));
357	if (master == NULL) {
358		dev_dbg(&pdev->dev, "spi_alloc_master failed\n");
359		return -ENOMEM;
360	}
361
362	mcfqspi = spi_master_get_devdata(master);
363
364	mcfqspi->iobase = devm_platform_ioremap_resource(pdev, 0);
 
365	if (IS_ERR(mcfqspi->iobase)) {
366		status = PTR_ERR(mcfqspi->iobase);
367		goto fail0;
368	}
369
370	mcfqspi->irq = platform_get_irq(pdev, 0);
371	if (mcfqspi->irq < 0) {
372		dev_dbg(&pdev->dev, "platform_get_irq failed\n");
373		status = -ENXIO;
374		goto fail0;
375	}
376
377	status = devm_request_irq(&pdev->dev, mcfqspi->irq, mcfqspi_irq_handler,
378				0, pdev->name, mcfqspi);
379	if (status) {
380		dev_dbg(&pdev->dev, "request_irq failed\n");
381		goto fail0;
382	}
383
384	mcfqspi->clk = devm_clk_get(&pdev->dev, "qspi_clk");
385	if (IS_ERR(mcfqspi->clk)) {
386		dev_dbg(&pdev->dev, "clk_get failed\n");
387		status = PTR_ERR(mcfqspi->clk);
388		goto fail0;
389	}
390	clk_prepare_enable(mcfqspi->clk);
391
392	master->bus_num = pdata->bus_num;
393	master->num_chipselect = pdata->num_chipselect;
394
395	mcfqspi->cs_control = pdata->cs_control;
396	status = mcfqspi_cs_setup(mcfqspi);
397	if (status) {
398		dev_dbg(&pdev->dev, "error initializing cs_control\n");
399		goto fail1;
400	}
401
402	init_waitqueue_head(&mcfqspi->waitq);
403
404	master->mode_bits = SPI_CS_HIGH | SPI_CPOL | SPI_CPHA;
405	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16);
406	master->setup = mcfqspi_setup;
407	master->set_cs = mcfqspi_set_cs;
408	master->transfer_one = mcfqspi_transfer_one;
409	master->auto_runtime_pm = true;
410
411	platform_set_drvdata(pdev, master);
412	pm_runtime_enable(&pdev->dev);
413
414	status = devm_spi_register_master(&pdev->dev, master);
415	if (status) {
416		dev_dbg(&pdev->dev, "spi_register_master failed\n");
417		goto fail2;
418	}
419
420	dev_info(&pdev->dev, "Coldfire QSPI bus driver\n");
421
422	return 0;
423
424fail2:
425	pm_runtime_disable(&pdev->dev);
426	mcfqspi_cs_teardown(mcfqspi);
427fail1:
428	clk_disable_unprepare(mcfqspi->clk);
429fail0:
430	spi_master_put(master);
431
432	dev_dbg(&pdev->dev, "Coldfire QSPI probe failed\n");
433
434	return status;
435}
436
437static int mcfqspi_remove(struct platform_device *pdev)
438{
439	struct spi_master *master = platform_get_drvdata(pdev);
440	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
441
442	pm_runtime_disable(&pdev->dev);
443	/* disable the hardware (set the baud rate to 0) */
444	mcfqspi_wr_qmr(mcfqspi, MCFQSPI_QMR_MSTR);
445
446	mcfqspi_cs_teardown(mcfqspi);
447	clk_disable_unprepare(mcfqspi->clk);
448
449	return 0;
450}
451
452#ifdef CONFIG_PM_SLEEP
453static int mcfqspi_suspend(struct device *dev)
454{
455	struct spi_master *master = dev_get_drvdata(dev);
456	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
457	int ret;
458
459	ret = spi_master_suspend(master);
460	if (ret)
461		return ret;
462
463	clk_disable(mcfqspi->clk);
464
465	return 0;
466}
467
468static int mcfqspi_resume(struct device *dev)
469{
470	struct spi_master *master = dev_get_drvdata(dev);
471	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
472
473	clk_enable(mcfqspi->clk);
474
475	return spi_master_resume(master);
476}
477#endif
478
479#ifdef CONFIG_PM
480static int mcfqspi_runtime_suspend(struct device *dev)
481{
482	struct spi_master *master = dev_get_drvdata(dev);
483	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
484
485	clk_disable(mcfqspi->clk);
486
487	return 0;
488}
489
490static int mcfqspi_runtime_resume(struct device *dev)
491{
492	struct spi_master *master = dev_get_drvdata(dev);
493	struct mcfqspi *mcfqspi = spi_master_get_devdata(master);
494
495	clk_enable(mcfqspi->clk);
496
497	return 0;
498}
499#endif
500
501static const struct dev_pm_ops mcfqspi_pm = {
502	SET_SYSTEM_SLEEP_PM_OPS(mcfqspi_suspend, mcfqspi_resume)
503	SET_RUNTIME_PM_OPS(mcfqspi_runtime_suspend, mcfqspi_runtime_resume,
504			NULL)
505};
506
507static struct platform_driver mcfqspi_driver = {
508	.driver.name	= DRIVER_NAME,
509	.driver.owner	= THIS_MODULE,
510	.driver.pm	= &mcfqspi_pm,
511	.probe		= mcfqspi_probe,
512	.remove		= mcfqspi_remove,
513};
514module_platform_driver(mcfqspi_driver);
515
516MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
517MODULE_DESCRIPTION("Coldfire QSPI Controller Driver");
518MODULE_LICENSE("GPL");
519MODULE_ALIAS("platform:" DRIVER_NAME);
v4.17
 
  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);