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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");
v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * SH SPI bus driver
  4 *
  5 * Copyright (C) 2011  Renesas Solutions Corp.
  6 *
  7 * Based on pxa2xx_spi.c:
  8 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9 */
 10
 11#include <linux/module.h>
 12#include <linux/kernel.h>
 13#include <linux/sched.h>
 14#include <linux/errno.h>
 15#include <linux/timer.h>
 16#include <linux/delay.h>
 17#include <linux/list.h>
 18#include <linux/workqueue.h>
 19#include <linux/interrupt.h>
 20#include <linux/platform_device.h>
 21#include <linux/io.h>
 22#include <linux/spi/spi.h>
 23
 24#define SPI_SH_TBR		0x00
 25#define SPI_SH_RBR		0x00
 26#define SPI_SH_CR1		0x08
 27#define SPI_SH_CR2		0x10
 28#define SPI_SH_CR3		0x18
 29#define SPI_SH_CR4		0x20
 30#define SPI_SH_CR5		0x28
 31
 32/* CR1 */
 33#define SPI_SH_TBE		0x80
 34#define SPI_SH_TBF		0x40
 35#define SPI_SH_RBE		0x20
 36#define SPI_SH_RBF		0x10
 37#define SPI_SH_PFONRD		0x08
 38#define SPI_SH_SSDB		0x04
 39#define SPI_SH_SSD		0x02
 40#define SPI_SH_SSA		0x01
 41
 42/* CR2 */
 43#define SPI_SH_RSTF		0x80
 44#define SPI_SH_LOOPBK		0x40
 45#define SPI_SH_CPOL		0x20
 46#define SPI_SH_CPHA		0x10
 47#define SPI_SH_L1M0		0x08
 48
 49/* CR3 */
 50#define SPI_SH_MAX_BYTE		0xFF
 51
 52/* CR4 */
 53#define SPI_SH_TBEI		0x80
 54#define SPI_SH_TBFI		0x40
 55#define SPI_SH_RBEI		0x20
 56#define SPI_SH_RBFI		0x10
 57#define SPI_SH_WPABRT		0x04
 58#define SPI_SH_SSS		0x01
 59
 60/* CR8 */
 61#define SPI_SH_P1L0		0x80
 62#define SPI_SH_PP1L0		0x40
 63#define SPI_SH_MUXI		0x20
 64#define SPI_SH_MUXIRQ		0x10
 65
 66#define SPI_SH_FIFO_SIZE	32
 67#define SPI_SH_SEND_TIMEOUT	(3 * HZ)
 68#define SPI_SH_RECEIVE_TIMEOUT	(HZ >> 3)
 69
 70#undef DEBUG
 71
 72struct spi_sh_data {
 73	void __iomem *addr;
 74	int irq;
 75	struct spi_master *master;
 76	struct list_head queue;
 
 77	struct work_struct ws;
 78	unsigned long cr1;
 79	wait_queue_head_t wait;
 80	spinlock_t lock;
 81	int width;
 82};
 83
 84static void spi_sh_write(struct spi_sh_data *ss, unsigned long data,
 85			     unsigned long offset)
 86{
 87	if (ss->width == 8)
 88		iowrite8(data, ss->addr + (offset >> 2));
 89	else if (ss->width == 32)
 90		iowrite32(data, ss->addr + offset);
 91}
 92
 93static unsigned long spi_sh_read(struct spi_sh_data *ss, unsigned long offset)
 94{
 95	if (ss->width == 8)
 96		return ioread8(ss->addr + (offset >> 2));
 97	else if (ss->width == 32)
 98		return ioread32(ss->addr + offset);
 99	else
100		return 0;
101}
102
103static void spi_sh_set_bit(struct spi_sh_data *ss, unsigned long val,
104				unsigned long offset)
105{
106	unsigned long tmp;
107
108	tmp = spi_sh_read(ss, offset);
109	tmp |= val;
110	spi_sh_write(ss, tmp, offset);
111}
112
113static void spi_sh_clear_bit(struct spi_sh_data *ss, unsigned long val,
114				unsigned long offset)
115{
116	unsigned long tmp;
117
118	tmp = spi_sh_read(ss, offset);
119	tmp &= ~val;
120	spi_sh_write(ss, tmp, offset);
121}
122
123static void clear_fifo(struct spi_sh_data *ss)
124{
125	spi_sh_set_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
126	spi_sh_clear_bit(ss, SPI_SH_RSTF, SPI_SH_CR2);
127}
128
129static int spi_sh_wait_receive_buffer(struct spi_sh_data *ss)
130{
131	int timeout = 100000;
132
133	while (spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
134		udelay(10);
135		if (timeout-- < 0)
136			return -ETIMEDOUT;
137	}
138	return 0;
139}
140
141static int spi_sh_wait_write_buffer_empty(struct spi_sh_data *ss)
142{
143	int timeout = 100000;
144
145	while (!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBE)) {
146		udelay(10);
147		if (timeout-- < 0)
148			return -ETIMEDOUT;
149	}
150	return 0;
151}
152
153static int spi_sh_send(struct spi_sh_data *ss, struct spi_message *mesg,
154			struct spi_transfer *t)
155{
156	int i, retval = 0;
157	int remain = t->len;
158	int cur_len;
159	unsigned char *data;
 
160	long ret;
161
162	if (t->len)
163		spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
164
165	data = (unsigned char *)t->tx_buf;
166	while (remain > 0) {
167		cur_len = min(SPI_SH_FIFO_SIZE, remain);
168		for (i = 0; i < cur_len &&
169				!(spi_sh_read(ss, SPI_SH_CR4) &
170							SPI_SH_WPABRT) &&
171				!(spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_TBF);
172				i++)
173			spi_sh_write(ss, (unsigned long)data[i], SPI_SH_TBR);
174
175		if (spi_sh_read(ss, SPI_SH_CR4) & SPI_SH_WPABRT) {
176			/* Abort SPI operation */
177			spi_sh_set_bit(ss, SPI_SH_WPABRT, SPI_SH_CR4);
178			retval = -EIO;
179			break;
180		}
181
182		cur_len = i;
183
184		remain -= cur_len;
185		data += cur_len;
186
187		if (remain > 0) {
188			ss->cr1 &= ~SPI_SH_TBE;
189			spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
190			ret = wait_event_interruptible_timeout(ss->wait,
191						 ss->cr1 & SPI_SH_TBE,
192						 SPI_SH_SEND_TIMEOUT);
193			if (ret == 0 && !(ss->cr1 & SPI_SH_TBE)) {
194				printk(KERN_ERR "%s: timeout\n", __func__);
195				return -ETIMEDOUT;
196			}
197		}
198	}
199
200	if (list_is_last(&t->transfer_list, &mesg->transfers)) {
201		spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
 
 
202		spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
203
204		ss->cr1 &= ~SPI_SH_TBE;
205		spi_sh_set_bit(ss, SPI_SH_TBE, SPI_SH_CR4);
206		ret = wait_event_interruptible_timeout(ss->wait,
207					 ss->cr1 & SPI_SH_TBE,
208					 SPI_SH_SEND_TIMEOUT);
209		if (ret == 0 && (ss->cr1 & SPI_SH_TBE)) {
210			printk(KERN_ERR "%s: timeout\n", __func__);
211			return -ETIMEDOUT;
212		}
213	}
214
215	return retval;
216}
217
218static int spi_sh_receive(struct spi_sh_data *ss, struct spi_message *mesg,
219			  struct spi_transfer *t)
220{
221	int i;
222	int remain = t->len;
223	int cur_len;
224	unsigned char *data;
 
225	long ret;
226
227	if (t->len > SPI_SH_MAX_BYTE)
228		spi_sh_write(ss, SPI_SH_MAX_BYTE, SPI_SH_CR3);
229	else
230		spi_sh_write(ss, t->len, SPI_SH_CR3);
231
232	spi_sh_clear_bit(ss, SPI_SH_SSD | SPI_SH_SSDB, SPI_SH_CR1);
 
 
233	spi_sh_set_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
234
235	spi_sh_wait_write_buffer_empty(ss);
236
237	data = (unsigned char *)t->rx_buf;
238	while (remain > 0) {
239		if (remain >= SPI_SH_FIFO_SIZE) {
240			ss->cr1 &= ~SPI_SH_RBF;
241			spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
242			ret = wait_event_interruptible_timeout(ss->wait,
243						 ss->cr1 & SPI_SH_RBF,
244						 SPI_SH_RECEIVE_TIMEOUT);
245			if (ret == 0 &&
246			    spi_sh_read(ss, SPI_SH_CR1) & SPI_SH_RBE) {
247				printk(KERN_ERR "%s: timeout\n", __func__);
248				return -ETIMEDOUT;
249			}
250		}
251
252		cur_len = min(SPI_SH_FIFO_SIZE, remain);
253		for (i = 0; i < cur_len; i++) {
254			if (spi_sh_wait_receive_buffer(ss))
255				break;
256			data[i] = (unsigned char)spi_sh_read(ss, SPI_SH_RBR);
257		}
258
259		remain -= cur_len;
260		data += cur_len;
261	}
262
263	/* deassert CS when SPI is receiving. */
264	if (t->len > SPI_SH_MAX_BYTE) {
265		clear_fifo(ss);
266		spi_sh_write(ss, 1, SPI_SH_CR3);
267	} else {
268		spi_sh_write(ss, 0, SPI_SH_CR3);
269	}
270
271	return 0;
272}
273
274static void spi_sh_work(struct work_struct *work)
275{
276	struct spi_sh_data *ss = container_of(work, struct spi_sh_data, ws);
277	struct spi_message *mesg;
278	struct spi_transfer *t;
279	unsigned long flags;
280	int ret;
281
282	pr_debug("%s: enter\n", __func__);
283
284	spin_lock_irqsave(&ss->lock, flags);
285	while (!list_empty(&ss->queue)) {
286		mesg = list_entry(ss->queue.next, struct spi_message, queue);
287		list_del_init(&mesg->queue);
288
289		spin_unlock_irqrestore(&ss->lock, flags);
290		list_for_each_entry(t, &mesg->transfers, transfer_list) {
291			pr_debug("tx_buf = %p, rx_buf = %p\n",
292					t->tx_buf, t->rx_buf);
293			pr_debug("len = %d, delay_usecs = %d\n",
294					t->len, t->delay_usecs);
295
296			if (t->tx_buf) {
297				ret = spi_sh_send(ss, mesg, t);
298				if (ret < 0)
299					goto error;
300			}
301			if (t->rx_buf) {
302				ret = spi_sh_receive(ss, mesg, t);
303				if (ret < 0)
304					goto error;
305			}
306			mesg->actual_length += t->len;
307		}
308		spin_lock_irqsave(&ss->lock, flags);
309
310		mesg->status = 0;
311		if (mesg->complete)
312			mesg->complete(mesg->context);
313	}
314
315	clear_fifo(ss);
316	spi_sh_set_bit(ss, SPI_SH_SSD, SPI_SH_CR1);
317	udelay(100);
318
319	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
320			 SPI_SH_CR1);
321
322	clear_fifo(ss);
323
324	spin_unlock_irqrestore(&ss->lock, flags);
325
326	return;
327
328 error:
329	mesg->status = ret;
330	if (mesg->complete)
331		mesg->complete(mesg->context);
332
333	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
334			 SPI_SH_CR1);
335	clear_fifo(ss);
336
337}
338
339static int spi_sh_setup(struct spi_device *spi)
340{
341	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
342
 
 
 
343	pr_debug("%s: enter\n", __func__);
344
345	spi_sh_write(ss, 0xfe, SPI_SH_CR1);	/* SPI sycle stop */
346	spi_sh_write(ss, 0x00, SPI_SH_CR1);	/* CR1 init */
347	spi_sh_write(ss, 0x00, SPI_SH_CR3);	/* CR3 init */
348
349	clear_fifo(ss);
350
351	/* 1/8 clock */
352	spi_sh_write(ss, spi_sh_read(ss, SPI_SH_CR2) | 0x07, SPI_SH_CR2);
353	udelay(10);
354
355	return 0;
356}
357
358static int spi_sh_transfer(struct spi_device *spi, struct spi_message *mesg)
359{
360	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
361	unsigned long flags;
362
363	pr_debug("%s: enter\n", __func__);
364	pr_debug("\tmode = %02x\n", spi->mode);
365
366	spin_lock_irqsave(&ss->lock, flags);
367
368	mesg->actual_length = 0;
369	mesg->status = -EINPROGRESS;
370
371	spi_sh_clear_bit(ss, SPI_SH_SSA, SPI_SH_CR1);
372
373	list_add_tail(&mesg->queue, &ss->queue);
374	schedule_work(&ss->ws);
375
376	spin_unlock_irqrestore(&ss->lock, flags);
377
378	return 0;
379}
380
381static void spi_sh_cleanup(struct spi_device *spi)
382{
383	struct spi_sh_data *ss = spi_master_get_devdata(spi->master);
384
385	pr_debug("%s: enter\n", __func__);
386
387	spi_sh_clear_bit(ss, SPI_SH_SSA | SPI_SH_SSDB | SPI_SH_SSD,
388			 SPI_SH_CR1);
389}
390
391static irqreturn_t spi_sh_irq(int irq, void *_ss)
392{
393	struct spi_sh_data *ss = (struct spi_sh_data *)_ss;
394	unsigned long cr1;
395
396	cr1 = spi_sh_read(ss, SPI_SH_CR1);
397	if (cr1 & SPI_SH_TBE)
398		ss->cr1 |= SPI_SH_TBE;
399	if (cr1 & SPI_SH_TBF)
400		ss->cr1 |= SPI_SH_TBF;
401	if (cr1 & SPI_SH_RBE)
402		ss->cr1 |= SPI_SH_RBE;
403	if (cr1 & SPI_SH_RBF)
404		ss->cr1 |= SPI_SH_RBF;
405
406	if (ss->cr1) {
407		spi_sh_clear_bit(ss, ss->cr1, SPI_SH_CR4);
408		wake_up(&ss->wait);
409	}
410
411	return IRQ_HANDLED;
412}
413
414static int spi_sh_remove(struct platform_device *pdev)
415{
416	struct spi_sh_data *ss = platform_get_drvdata(pdev);
417
418	spi_unregister_master(ss->master);
419	flush_work(&ss->ws);
420	free_irq(ss->irq, ss);
 
421
422	return 0;
423}
424
425static int spi_sh_probe(struct platform_device *pdev)
426{
427	struct resource *res;
428	struct spi_master *master;
429	struct spi_sh_data *ss;
430	int ret, irq;
431
432	/* get base addr */
433	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
434	if (unlikely(res == NULL)) {
435		dev_err(&pdev->dev, "invalid resource\n");
436		return -EINVAL;
437	}
438
439	irq = platform_get_irq(pdev, 0);
440	if (irq < 0)
441		return irq;
 
 
442
443	master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data));
444	if (master == NULL) {
445		dev_err(&pdev->dev, "spi_alloc_master error.\n");
446		return -ENOMEM;
447	}
448
449	ss = spi_master_get_devdata(master);
450	platform_set_drvdata(pdev, ss);
451
452	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
453	case IORESOURCE_MEM_8BIT:
454		ss->width = 8;
455		break;
456	case IORESOURCE_MEM_32BIT:
457		ss->width = 32;
458		break;
459	default:
460		dev_err(&pdev->dev, "No support width\n");
461		ret = -ENODEV;
462		goto error1;
463	}
464	ss->irq = irq;
465	ss->master = master;
466	ss->addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
467	if (ss->addr == NULL) {
468		dev_err(&pdev->dev, "ioremap error.\n");
469		ret = -ENOMEM;
470		goto error1;
471	}
472	INIT_LIST_HEAD(&ss->queue);
473	spin_lock_init(&ss->lock);
474	INIT_WORK(&ss->ws, spi_sh_work);
475	init_waitqueue_head(&ss->wait);
 
 
 
 
 
 
 
476
477	ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss);
478	if (ret < 0) {
479		dev_err(&pdev->dev, "request_irq error\n");
480		goto error1;
481	}
482
483	master->num_chipselect = 2;
484	master->bus_num = pdev->id;
485	master->setup = spi_sh_setup;
486	master->transfer = spi_sh_transfer;
487	master->cleanup = spi_sh_cleanup;
488
489	ret = spi_register_master(master);
490	if (ret < 0) {
491		printk(KERN_ERR "spi_register_master error.\n");
492		goto error3;
493	}
494
495	return 0;
496
 
 
497 error3:
498	free_irq(irq, ss);
 
 
499 error1:
500	spi_master_put(master);
501
502	return ret;
503}
504
505static struct platform_driver spi_sh_driver = {
506	.probe = spi_sh_probe,
507	.remove = spi_sh_remove,
508	.driver = {
509		.name = "sh_spi",
 
510	},
511};
512module_platform_driver(spi_sh_driver);
513
514MODULE_DESCRIPTION("SH SPI bus driver");
515MODULE_LICENSE("GPL v2");
516MODULE_AUTHOR("Yoshihiro Shimoda");
517MODULE_ALIAS("platform:sh_spi");