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v4.6
  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);
v4.10.11
  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);