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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);
v3.1
 
  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);