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v3.1
  1/*
  2 * SH SPI bus driver
  3 *
  4 * Copyright (C) 2011  Renesas Solutions Corp.
  5 *
  6 * Based on pxa2xx_spi.c:
  7 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; version 2 of the License.
 12 *
 13 * This program is distributed in the hope that it will be useful,
 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16 * GNU General Public License for more details.
 17 *
 18 * You should have received a copy of the GNU General Public License
 19 * along with this program; if not, write to the Free Software
 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 21 *
 22 */
 23
 24#include <linux/module.h>
 25#include <linux/kernel.h>
 26#include <linux/sched.h>
 27#include <linux/errno.h>
 28#include <linux/timer.h>
 29#include <linux/delay.h>
 30#include <linux/list.h>
 31#include <linux/workqueue.h>
 32#include <linux/interrupt.h>
 33#include <linux/platform_device.h>
 34#include <linux/io.h>
 35#include <linux/spi/spi.h>
 36
 37#define SPI_SH_TBR		0x00
 38#define SPI_SH_RBR		0x00
 39#define SPI_SH_CR1		0x08
 40#define SPI_SH_CR2		0x10
 41#define SPI_SH_CR3		0x18
 42#define SPI_SH_CR4		0x20
 43#define SPI_SH_CR5		0x28
 44
 45/* CR1 */
 46#define SPI_SH_TBE		0x80
 47#define SPI_SH_TBF		0x40
 48#define SPI_SH_RBE		0x20
 49#define SPI_SH_RBF		0x10
 50#define SPI_SH_PFONRD		0x08
 51#define SPI_SH_SSDB		0x04
 52#define SPI_SH_SSD		0x02
 53#define SPI_SH_SSA		0x01
 54
 55/* CR2 */
 56#define SPI_SH_RSTF		0x80
 57#define SPI_SH_LOOPBK		0x40
 58#define SPI_SH_CPOL		0x20
 59#define SPI_SH_CPHA		0x10
 60#define SPI_SH_L1M0		0x08
 61
 62/* CR3 */
 63#define SPI_SH_MAX_BYTE		0xFF
 64
 65/* CR4 */
 66#define SPI_SH_TBEI		0x80
 67#define SPI_SH_TBFI		0x40
 68#define SPI_SH_RBEI		0x20
 69#define SPI_SH_RBFI		0x10
 70#define SPI_SH_WPABRT		0x04
 71#define SPI_SH_SSS		0x01
 72
 73/* CR8 */
 74#define SPI_SH_P1L0		0x80
 75#define SPI_SH_PP1L0		0x40
 76#define SPI_SH_MUXI		0x20
 77#define SPI_SH_MUXIRQ		0x10
 78
 79#define SPI_SH_FIFO_SIZE	32
 80#define SPI_SH_SEND_TIMEOUT	(3 * HZ)
 81#define SPI_SH_RECEIVE_TIMEOUT	(HZ >> 3)
 82
 83#undef DEBUG
 84
 85struct spi_sh_data {
 86	void __iomem *addr;
 87	int irq;
 88	struct spi_master *master;
 89	struct list_head queue;
 90	struct workqueue_struct *workqueue;
 91	struct work_struct ws;
 92	unsigned long cr1;
 93	wait_queue_head_t wait;
 94	spinlock_t lock;
 
 95};
 96
 97static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
 98			     unsigned long offset)
 99{
100	writel(data, ss->addr + offset);
 
 
 
101}
102
103static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
104{
105	return readl(ss->addr + offset);
 
 
 
 
 
106}
107
108static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
109				unsigned long offset)
110{
111	unsigned long tmp;
112
113	tmp = spi_sh_read(ss, offset);
114	tmp |= val;
115	spi_sh_write(ss, tmp, offset);
116}
117
118static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
119				unsigned long offset)
120{
121	unsigned long tmp;
122
123	tmp = spi_sh_read(ss, offset);
124	tmp &= ~val;
125	spi_sh_write(ss, tmp, offset);
126}
127
128static void clear_fifo(struct spi_sh_data *ss)
129{
130	spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
131	spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
132}
133
134static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss)
135{
136	int timeout = 100000;
137
138	while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
139		udelay(10);
140		if (timeout-- < 0)
141			return -ETIMEDOUT;
142	}
143	return 0;
144}
145
146static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss)
147{
148	int timeout = 100000;
149
150	while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
151		udelay(10);
152		if (timeout-- < 0)
153			return -ETIMEDOUT;
154	}
155	return 0;
156}
157
158static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
159			struct spi_transfer *t)
160{
161	int i, retval = 0;
162	int remain = t->len;
163	int cur_len;
164	unsigned char *data;
165	unsigned long tmp;
166	long ret;
167
168	if (t->len)
169		spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
170
171	data = (unsigned char *)t->tx_buf;
172	while (remain > 0) {
173		cur_len = min(SPI_SH_FIFO_SIZE, remain);
174		for (i = 0; i < cur_len &&
175				!(spi_sh_read(ss, SPI_SH_CR4) &
176							SPI_SH_WPABRT) &&
177				!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
178				i++)
179			spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
180
181		if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
182			/* Abort SPI operation */
183			spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
184			retval = -EIO;
185			break;
186		}
187
188		cur_len = i;
189
190		remain -= cur_len;
191		data += cur_len;
192
193		if (remain > 0) {
194			ss->cr1 &= ~SPI_SH_TBE;
195			spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
196			ret = wait_event_interruptible_timeout(ss->wait,
197						 ss->cr1 & SPI_SH_TBE,
198						 SPI_SH_SEND_TIMEOUT);
199			if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) {
200				printk(KERN_ERR "%s: timeout\n", __func__);
201				return -ETIMEDOUT;
202			}
203		}
204	}
205
206	if (list_is_last(&t->transfer_list, &mesg->transfers)) {
207		tmp = spi_sh_read(ss, SPI_SH_CR1);
208		tmp = tmp & ~(SPI_SH_SSD | SPI_SH_SSDB);
209		spi_sh_write(ss, tmp, SPI_SH_CR1);
210		spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
211
212		ss->cr1 &= ~SPI_SH_TBE;
213		spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
214		ret = wait_event_interruptible_timeout(ss->wait,
215					 ss->cr1 & SPI_SH_TBE,
216					 SPI_SH_SEND_TIMEOUT);
217		if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) {
218			printk(KERN_ERR "%s: timeout\n", __func__);
219			return -ETIMEDOUT;
220		}
221	}
222
223	return retval;
224}
225
226static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
227			  struct spi_transfer *t)
228{
229	int i;
230	int remain = t->len;
231	int cur_len;
232	unsigned char *data;
233	unsigned long tmp;
234	long ret;
235
236	if (t->len > SPI_SH_MAX_BYTE)
237		spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
238	else
239		spi_sh_write(ss, t->len, SPI_SH_CR3);
240
241	tmp = spi_sh_read(ss, SPI_SH_CR1);
242	tmp = tmp & ~(SPI_SH_SSD | SPI_SH_SSDB);
243	spi_sh_write(ss, tmp, SPI_SH_CR1);
244	spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
245
246	spi_sh_wait_write_buffer_empty(ss);
247
248	data = (unsigned char *)t->rx_buf;
249	while (remain > 0) {
250		if (remain >= SPI_SH_FIFO_SIZE) {
251			ss->cr1 &= ~SPI_SH_RBF;
252			spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
253			ret = wait_event_interruptible_timeout(ss->wait,
254						 ss->cr1 & SPI_SH_RBF,
255						 SPI_SH_RECEIVE_TIMEOUT);
256			if (ret == 0 &&
257			    spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
258				printk(KERN_ERR "%s: timeout\n", __func__);
259				return -ETIMEDOUT;
260			}
261		}
262
263		cur_len = min(SPI_SH_FIFO_SIZE, remain);
264		for (i = 0; i < cur_len; i++) {
265			if (spi_sh_wait_receive_buffer(ss))
266				break;
267			data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
268		}
269
270		remain -= cur_len;
271		data += cur_len;
272	}
273
274	/* deassert CS when SPI is receiving. */
275	if (t->len > SPI_SH_MAX_BYTE) {
276		clear_fifo(ss);
277		spi_sh_write(ss, 1, SPI_SH_CR3);
278	} else {
279		spi_sh_write(ss, 0, SPI_SH_CR3);
280	}
281
282	return 0;
283}
284
285static void spi_sh_work(struct work_struct *work)
286{
287	struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws);
288	struct spi_message *mesg;
289	struct spi_transfer *t;
290	unsigned long flags;
291	int ret;
292
293	pr_debug("%s: enter\n", __func__);
294
295	spin_lock_irqsave(&ss->lock, flags);
296	while (!list_empty(&ss->queue)) {
297		mesg = list_entry(ss->queue.next, struct spi_message, queue);
298		list_del_init(&mesg->queue);
299
300		spin_unlock_irqrestore(&ss->lock, flags);
301		list_for_each_entry(t, &mesg->transfers, transfer_list) {
302			pr_debug("tx_buf = %p, rx_buf = %p\n",
303					t->tx_buf, t->rx_buf);
304			pr_debug("len = %d, delay_usecs = %d\n",
305					t->len, t->delay_usecs);
306
307			if (t->tx_buf) {
308				ret = spi_sh_send(ss, mesg, t);
309				if (ret < 0)
310					goto error;
311			}
312			if (t->rx_buf) {
313				ret = spi_sh_receive(ss, mesg, t);
314				if (ret < 0)
315					goto error;
316			}
317			mesg->actual_length += t->len;
318		}
319		spin_lock_irqsave(&ss->lock, flags);
320
321		mesg->status = 0;
322		mesg->complete(mesg->context);
323	}
324
325	clear_fifo(ss);
326	spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
327	udelay(100);
328
329	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
330			 SPI_SH_CR1);
331
332	clear_fifo(ss);
333
334	spin_unlock_irqrestore(&ss->lock, flags);
335
336	return;
337
338 error:
339	mesg->status = ret;
340	mesg->complete(mesg->context);
341
342	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
343			 SPI_SH_CR1);
344	clear_fifo(ss);
345
346}
347
348static int spi_sh_setup(struct spi_device *spi)
349{
350	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
351
352	if (!spi->bits_per_word)
353		spi->bits_per_word = 8;
354
355	pr_debug("%s: enter\n", __func__);
356
357	spi_sh_write(ss, 0xfe, SPI_SH_CR1);	/* SPI sycle stop */
358	spi_sh_write(ss, 0x00, SPI_SH_CR1);	/* CR1 init */
359	spi_sh_write(ss, 0x00, SPI_SH_CR3);	/* CR3 init */
360
361	clear_fifo(ss);
362
363	/* 1/8 clock */
364	spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
365	udelay(10);
366
367	return 0;
368}
369
370static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg)
371{
372	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
373	unsigned long flags;
374
375	pr_debug("%s: enter\n", __func__);
376	pr_debug("\tmode = %02x\n", spi->mode);
377
378	spin_lock_irqsave(&ss->lock, flags);
379
380	mesg->actual_length = 0;
381	mesg->status = -EINPROGRESS;
382
383	spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
384
385	list_add_tail(&mesg->queue, &ss->queue);
386	queue_work(ss->workqueue, &ss->ws);
387
388	spin_unlock_irqrestore(&ss->lock, flags);
389
390	return 0;
391}
392
393static void spi_sh_cleanup(struct spi_device *spi)
394{
395	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
396
397	pr_debug("%s: enter\n", __func__);
398
399	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
400			 SPI_SH_CR1);
401}
402
403static irqreturn_t spi_sh_irq(int irq, void *_ss)
404{
405	struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
406	unsigned long cr1;
407
408	cr1 = spi_sh_read(ss, SPI_SH_CR1);
409	if (cr1 & SPI_SH_TBE)
410		ss->cr1 |= SPI_SH_TBE;
411	if (cr1 & SPI_SH_TBF)
412		ss->cr1 |= SPI_SH_TBF;
413	if (cr1 & SPI_SH_RBE)
414		ss->cr1 |= SPI_SH_RBE;
415	if (cr1 & SPI_SH_RBF)
416		ss->cr1 |= SPI_SH_RBF;
417
418	if (ss->cr1) {
419		spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
420		wake_up(&ss->wait);
421	}
422
423	return IRQ_HANDLED;
424}
425
426static int __devexit spi_sh_remove(struct platform_device *pdev)
427{
428	struct spi_sh_data *ss = dev_get_drvdata(&pdev->dev);
429
430	spi_unregister_master(ss->master);
431	destroy_workqueue(ss->workqueue);
432	free_irq(ss->irq, ss);
433	iounmap(ss->addr);
434
435	return 0;
436}
437
438static int __devinit spi_sh_probe(struct platform_device *pdev)
439{
440	struct resource *res;
441	struct spi_master *master;
442	struct spi_sh_data *ss;
443	int ret, irq;
444
445	/* get base addr */
446	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
447	if (unlikely(res == NULL)) {
448		dev_err(&pdev->dev, "invalid resource\n");
449		return -EINVAL;
450	}
451
452	irq = platform_get_irq(pdev, 0);
453	if (irq < 0) {
454		dev_err(&pdev->dev, "platform_get_irq error\n");
455		return -ENODEV;
456	}
457
458	master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data));
459	if (master == NULL) {
460		dev_err(&pdev->dev, "spi_alloc_master error.\n");
461		return -ENOMEM;
462	}
463
464	ss = spi_master_get_devdata(master);
465	dev_set_drvdata(&pdev->dev, ss);
466
 
 
 
 
 
 
 
 
 
 
 
 
467	ss->irq = irq;
468	ss->master = master;
469	ss->addr = ioremap(res->start, resource_size(res));
470	if (ss->addr == NULL) {
471		dev_err(&pdev->dev, "ioremap error.\n");
472		ret = -ENOMEM;
473		goto error1;
474	}
475	INIT_LIST_HEAD(&ss->queue);
476	spin_lock_init(&ss->lock);
477	INIT_WORK(&ss->ws, spi_sh_work);
478	init_waitqueue_head(&ss->wait);
479	ss->workqueue = create_singlethread_workqueue(
480					dev_name(master->dev.parent));
481	if (ss->workqueue == NULL) {
482		dev_err(&pdev->dev, "create workqueue error\n");
483		ret = -EBUSY;
484		goto error2;
485	}
486
487	ret = request_irq(irq, spi_sh_irq, IRQF_DISABLED, "spi_sh", ss);
488	if (ret < 0) {
489		dev_err(&pdev->dev, "request_irq error\n");
490		goto error3;
491	}
492
493	master->num_chipselect = 2;
494	master->bus_num = pdev->id;
495	master->setup = spi_sh_setup;
496	master->transfer = spi_sh_transfer;
497	master->cleanup = spi_sh_cleanup;
498
499	ret = spi_register_master(master);
500	if (ret < 0) {
501		printk(KERN_ERR "spi_register_master error.\n");
502		goto error4;
503	}
504
505	return 0;
506
507 error4:
508	free_irq(irq, ss);
509 error3:
510	destroy_workqueue(ss->workqueue);
511 error2:
512	iounmap(ss->addr);
513 error1:
514	spi_master_put(master);
515
516	return ret;
517}
518
519static struct platform_driver spi_sh_driver = {
520	.probe = spi_sh_probe,
521	.remove = __devexit_p(spi_sh_remove),
522	.driver = {
523		.name = "sh_spi",
524		.owner = THIS_MODULE,
525	},
526};
527
528static int __init spi_sh_init(void)
529{
530	return platform_driver_register(&spi_sh_driver);
531}
532module_init(spi_sh_init);
533
534static void __exit spi_sh_exit(void)
535{
536	platform_driver_unregister(&spi_sh_driver);
537}
538module_exit(spi_sh_exit);
539
540MODULE_DESCRIPTION("SH SPI bus driver");
541MODULE_LICENSE("GPL");
542MODULE_AUTHOR("Yoshihiro Shimoda");
543MODULE_ALIAS("platform:sh_spi");
v3.5.6
  1/*
  2 * SH SPI bus driver
  3 *
  4 * Copyright (C) 2011  Renesas Solutions Corp.
  5 *
  6 * Based on pxa2xx_spi.c:
  7 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; version 2 of the License.
 12 *
 13 * This program is distributed in the hope that it will be useful,
 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16 * GNU General Public License for more details.
 17 *
 18 * You should have received a copy of the GNU General Public License
 19 * along with this program; if not, write to the Free Software
 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 21 *
 22 */
 23
 24#include <linux/module.h>
 25#include <linux/kernel.h>
 26#include <linux/sched.h>
 27#include <linux/errno.h>
 28#include <linux/timer.h>
 29#include <linux/delay.h>
 30#include <linux/list.h>
 31#include <linux/workqueue.h>
 32#include <linux/interrupt.h>
 33#include <linux/platform_device.h>
 34#include <linux/io.h>
 35#include <linux/spi/spi.h>
 36
 37#define SPI_SH_TBR		0x00
 38#define SPI_SH_RBR		0x00
 39#define SPI_SH_CR1		0x08
 40#define SPI_SH_CR2		0x10
 41#define SPI_SH_CR3		0x18
 42#define SPI_SH_CR4		0x20
 43#define SPI_SH_CR5		0x28
 44
 45/* CR1 */
 46#define SPI_SH_TBE		0x80
 47#define SPI_SH_TBF		0x40
 48#define SPI_SH_RBE		0x20
 49#define SPI_SH_RBF		0x10
 50#define SPI_SH_PFONRD		0x08
 51#define SPI_SH_SSDB		0x04
 52#define SPI_SH_SSD		0x02
 53#define SPI_SH_SSA		0x01
 54
 55/* CR2 */
 56#define SPI_SH_RSTF		0x80
 57#define SPI_SH_LOOPBK		0x40
 58#define SPI_SH_CPOL		0x20
 59#define SPI_SH_CPHA		0x10
 60#define SPI_SH_L1M0		0x08
 61
 62/* CR3 */
 63#define SPI_SH_MAX_BYTE		0xFF
 64
 65/* CR4 */
 66#define SPI_SH_TBEI		0x80
 67#define SPI_SH_TBFI		0x40
 68#define SPI_SH_RBEI		0x20
 69#define SPI_SH_RBFI		0x10
 70#define SPI_SH_WPABRT		0x04
 71#define SPI_SH_SSS		0x01
 72
 73/* CR8 */
 74#define SPI_SH_P1L0		0x80
 75#define SPI_SH_PP1L0		0x40
 76#define SPI_SH_MUXI		0x20
 77#define SPI_SH_MUXIRQ		0x10
 78
 79#define SPI_SH_FIFO_SIZE	32
 80#define SPI_SH_SEND_TIMEOUT	(3 * HZ)
 81#define SPI_SH_RECEIVE_TIMEOUT	(HZ >> 3)
 82
 83#undef DEBUG
 84
 85struct spi_sh_data {
 86	void __iomem *addr;
 87	int irq;
 88	struct spi_master *master;
 89	struct list_head queue;
 90	struct workqueue_struct *workqueue;
 91	struct work_struct ws;
 92	unsigned long cr1;
 93	wait_queue_head_t wait;
 94	spinlock_t lock;
 95	int width;
 96};
 97
 98static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
 99			     unsigned long offset)
100{
101	if (ss->width == 8)
102		iowrite8(data, ss->addr + (offset >> 2));
103	else if (ss->width == 32)
104		iowrite32(data, ss->addr + offset);
105}
106
107static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
108{
109	if (ss->width == 8)
110		return ioread8(ss->addr + (offset >> 2));
111	else if (ss->width == 32)
112		return ioread32(ss->addr + offset);
113	else
114		return 0;
115}
116
117static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
118				unsigned long offset)
119{
120	unsigned long tmp;
121
122	tmp = spi_sh_read(ss, offset);
123	tmp |= val;
124	spi_sh_write(ss, tmp, offset);
125}
126
127static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
128				unsigned long offset)
129{
130	unsigned long tmp;
131
132	tmp = spi_sh_read(ss, offset);
133	tmp &= ~val;
134	spi_sh_write(ss, tmp, offset);
135}
136
137static void clear_fifo(struct spi_sh_data *ss)
138{
139	spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
140	spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
141}
142
143static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss)
144{
145	int timeout = 100000;
146
147	while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
148		udelay(10);
149		if (timeout-- < 0)
150			return -ETIMEDOUT;
151	}
152	return 0;
153}
154
155static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss)
156{
157	int timeout = 100000;
158
159	while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
160		udelay(10);
161		if (timeout-- < 0)
162			return -ETIMEDOUT;
163	}
164	return 0;
165}
166
167static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
168			struct spi_transfer *t)
169{
170	int i, retval = 0;
171	int remain = t->len;
172	int cur_len;
173	unsigned char *data;
174	unsigned long tmp;
175	long ret;
176
177	if (t->len)
178		spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
179
180	data = (unsigned char *)t->tx_buf;
181	while (remain > 0) {
182		cur_len = min(SPI_SH_FIFO_SIZE, remain);
183		for (i = 0; i < cur_len &&
184				!(spi_sh_read(ss, SPI_SH_CR4) &
185							SPI_SH_WPABRT) &&
186				!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
187				i++)
188			spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
189
190		if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
191			/* Abort SPI operation */
192			spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
193			retval = -EIO;
194			break;
195		}
196
197		cur_len = i;
198
199		remain -= cur_len;
200		data += cur_len;
201
202		if (remain > 0) {
203			ss->cr1 &= ~SPI_SH_TBE;
204			spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
205			ret = wait_event_interruptible_timeout(ss->wait,
206						 ss->cr1 & SPI_SH_TBE,
207						 SPI_SH_SEND_TIMEOUT);
208			if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) {
209				printk(KERN_ERR "%s: timeout\n", __func__);
210				return -ETIMEDOUT;
211			}
212		}
213	}
214
215	if (list_is_last(&t->transfer_list, &mesg->transfers)) {
216		tmp = spi_sh_read(ss, SPI_SH_CR1);
217		tmp = tmp & ~(SPI_SH_SSD | SPI_SH_SSDB);
218		spi_sh_write(ss, tmp, SPI_SH_CR1);
219		spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
220
221		ss->cr1 &= ~SPI_SH_TBE;
222		spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
223		ret = wait_event_interruptible_timeout(ss->wait,
224					 ss->cr1 & SPI_SH_TBE,
225					 SPI_SH_SEND_TIMEOUT);
226		if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) {
227			printk(KERN_ERR "%s: timeout\n", __func__);
228			return -ETIMEDOUT;
229		}
230	}
231
232	return retval;
233}
234
235static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
236			  struct spi_transfer *t)
237{
238	int i;
239	int remain = t->len;
240	int cur_len;
241	unsigned char *data;
242	unsigned long tmp;
243	long ret;
244
245	if (t->len > SPI_SH_MAX_BYTE)
246		spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
247	else
248		spi_sh_write(ss, t->len, SPI_SH_CR3);
249
250	tmp = spi_sh_read(ss, SPI_SH_CR1);
251	tmp = tmp & ~(SPI_SH_SSD | SPI_SH_SSDB);
252	spi_sh_write(ss, tmp, SPI_SH_CR1);
253	spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
254
255	spi_sh_wait_write_buffer_empty(ss);
256
257	data = (unsigned char *)t->rx_buf;
258	while (remain > 0) {
259		if (remain >= SPI_SH_FIFO_SIZE) {
260			ss->cr1 &= ~SPI_SH_RBF;
261			spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
262			ret = wait_event_interruptible_timeout(ss->wait,
263						 ss->cr1 & SPI_SH_RBF,
264						 SPI_SH_RECEIVE_TIMEOUT);
265			if (ret == 0 &&
266			    spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
267				printk(KERN_ERR "%s: timeout\n", __func__);
268				return -ETIMEDOUT;
269			}
270		}
271
272		cur_len = min(SPI_SH_FIFO_SIZE, remain);
273		for (i = 0; i < cur_len; i++) {
274			if (spi_sh_wait_receive_buffer(ss))
275				break;
276			data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
277		}
278
279		remain -= cur_len;
280		data += cur_len;
281	}
282
283	/* deassert CS when SPI is receiving. */
284	if (t->len > SPI_SH_MAX_BYTE) {
285		clear_fifo(ss);
286		spi_sh_write(ss, 1, SPI_SH_CR3);
287	} else {
288		spi_sh_write(ss, 0, SPI_SH_CR3);
289	}
290
291	return 0;
292}
293
294static void spi_sh_work(struct work_struct *work)
295{
296	struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws);
297	struct spi_message *mesg;
298	struct spi_transfer *t;
299	unsigned long flags;
300	int ret;
301
302	pr_debug("%s: enter\n", __func__);
303
304	spin_lock_irqsave(&ss->lock, flags);
305	while (!list_empty(&ss->queue)) {
306		mesg = list_entry(ss->queue.next, struct spi_message, queue);
307		list_del_init(&mesg->queue);
308
309		spin_unlock_irqrestore(&ss->lock, flags);
310		list_for_each_entry(t, &mesg->transfers, transfer_list) {
311			pr_debug("tx_buf = %p, rx_buf = %p\n",
312					t->tx_buf, t->rx_buf);
313			pr_debug("len = %d, delay_usecs = %d\n",
314					t->len, t->delay_usecs);
315
316			if (t->tx_buf) {
317				ret = spi_sh_send(ss, mesg, t);
318				if (ret < 0)
319					goto error;
320			}
321			if (t->rx_buf) {
322				ret = spi_sh_receive(ss, mesg, t);
323				if (ret < 0)
324					goto error;
325			}
326			mesg->actual_length += t->len;
327		}
328		spin_lock_irqsave(&ss->lock, flags);
329
330		mesg->status = 0;
331		mesg->complete(mesg->context);
332	}
333
334	clear_fifo(ss);
335	spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
336	udelay(100);
337
338	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
339			 SPI_SH_CR1);
340
341	clear_fifo(ss);
342
343	spin_unlock_irqrestore(&ss->lock, flags);
344
345	return;
346
347 error:
348	mesg->status = ret;
349	mesg->complete(mesg->context);
350
351	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
352			 SPI_SH_CR1);
353	clear_fifo(ss);
354
355}
356
357static int spi_sh_setup(struct spi_device *spi)
358{
359	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
360
361	if (!spi->bits_per_word)
362		spi->bits_per_word = 8;
363
364	pr_debug("%s: enter\n", __func__);
365
366	spi_sh_write(ss, 0xfe, SPI_SH_CR1);	/* SPI sycle stop */
367	spi_sh_write(ss, 0x00, SPI_SH_CR1);	/* CR1 init */
368	spi_sh_write(ss, 0x00, SPI_SH_CR3);	/* CR3 init */
369
370	clear_fifo(ss);
371
372	/* 1/8 clock */
373	spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
374	udelay(10);
375
376	return 0;
377}
378
379static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg)
380{
381	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
382	unsigned long flags;
383
384	pr_debug("%s: enter\n", __func__);
385	pr_debug("\tmode = %02x\n", spi->mode);
386
387	spin_lock_irqsave(&ss->lock, flags);
388
389	mesg->actual_length = 0;
390	mesg->status = -EINPROGRESS;
391
392	spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
393
394	list_add_tail(&mesg->queue, &ss->queue);
395	queue_work(ss->workqueue, &ss->ws);
396
397	spin_unlock_irqrestore(&ss->lock, flags);
398
399	return 0;
400}
401
402static void spi_sh_cleanup(struct spi_device *spi)
403{
404	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
405
406	pr_debug("%s: enter\n", __func__);
407
408	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
409			 SPI_SH_CR1);
410}
411
412static irqreturn_t spi_sh_irq(int irq, void *_ss)
413{
414	struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
415	unsigned long cr1;
416
417	cr1 = spi_sh_read(ss, SPI_SH_CR1);
418	if (cr1 & SPI_SH_TBE)
419		ss->cr1 |= SPI_SH_TBE;
420	if (cr1 & SPI_SH_TBF)
421		ss->cr1 |= SPI_SH_TBF;
422	if (cr1 & SPI_SH_RBE)
423		ss->cr1 |= SPI_SH_RBE;
424	if (cr1 & SPI_SH_RBF)
425		ss->cr1 |= SPI_SH_RBF;
426
427	if (ss->cr1) {
428		spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
429		wake_up(&ss->wait);
430	}
431
432	return IRQ_HANDLED;
433}
434
435static int __devexit spi_sh_remove(struct platform_device *pdev)
436{
437	struct spi_sh_data *ss = dev_get_drvdata(&pdev->dev);
438
439	spi_unregister_master(ss->master);
440	destroy_workqueue(ss->workqueue);
441	free_irq(ss->irq, ss);
442	iounmap(ss->addr);
443
444	return 0;
445}
446
447static int __devinit spi_sh_probe(struct platform_device *pdev)
448{
449	struct resource *res;
450	struct spi_master *master;
451	struct spi_sh_data *ss;
452	int ret, irq;
453
454	/* get base addr */
455	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
456	if (unlikely(res == NULL)) {
457		dev_err(&pdev->dev, "invalid resource\n");
458		return -EINVAL;
459	}
460
461	irq = platform_get_irq(pdev, 0);
462	if (irq < 0) {
463		dev_err(&pdev->dev, "platform_get_irq error\n");
464		return -ENODEV;
465	}
466
467	master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data));
468	if (master == NULL) {
469		dev_err(&pdev->dev, "spi_alloc_master error.\n");
470		return -ENOMEM;
471	}
472
473	ss = spi_master_get_devdata(master);
474	dev_set_drvdata(&pdev->dev, ss);
475
476	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
477	case IORESOURCE_MEM_8BIT:
478		ss->width = 8;
479		break;
480	case IORESOURCE_MEM_32BIT:
481		ss->width = 32;
482		break;
483	default:
484		dev_err(&pdev->dev, "No support width\n");
485		ret = -ENODEV;
486		goto error1;
487	}
488	ss->irq = irq;
489	ss->master = master;
490	ss->addr = ioremap(res->start, resource_size(res));
491	if (ss->addr == NULL) {
492		dev_err(&pdev->dev, "ioremap error.\n");
493		ret = -ENOMEM;
494		goto error1;
495	}
496	INIT_LIST_HEAD(&ss->queue);
497	spin_lock_init(&ss->lock);
498	INIT_WORK(&ss->ws, spi_sh_work);
499	init_waitqueue_head(&ss->wait);
500	ss->workqueue = create_singlethread_workqueue(
501					dev_name(master->dev.parent));
502	if (ss->workqueue == NULL) {
503		dev_err(&pdev->dev, "create workqueue error\n");
504		ret = -EBUSY;
505		goto error2;
506	}
507
508	ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss);
509	if (ret < 0) {
510		dev_err(&pdev->dev, "request_irq error\n");
511		goto error3;
512	}
513
514	master->num_chipselect = 2;
515	master->bus_num = pdev->id;
516	master->setup = spi_sh_setup;
517	master->transfer = spi_sh_transfer;
518	master->cleanup = spi_sh_cleanup;
519
520	ret = spi_register_master(master);
521	if (ret < 0) {
522		printk(KERN_ERR "spi_register_master error.\n");
523		goto error4;
524	}
525
526	return 0;
527
528 error4:
529	free_irq(irq, ss);
530 error3:
531	destroy_workqueue(ss->workqueue);
532 error2:
533	iounmap(ss->addr);
534 error1:
535	spi_master_put(master);
536
537	return ret;
538}
539
540static struct platform_driver spi_sh_driver = {
541	.probe = spi_sh_probe,
542	.remove = __devexit_p(spi_sh_remove),
543	.driver = {
544		.name = "sh_spi",
545		.owner = THIS_MODULE,
546	},
547};
548module_platform_driver(spi_sh_driver);
 
 
 
 
 
 
 
 
 
 
 
549
550MODULE_DESCRIPTION("SH SPI bus driver");
551MODULE_LICENSE("GPL");
552MODULE_AUTHOR("Yoshihiro Shimoda");
553MODULE_ALIAS("platform:sh_spi");