1/* OMAP SSI driver.
2 *
3 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
4 * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org>
5 *
6 * Contact: Carlos Chinea <carlos.chinea@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 */
22
23#include <linux/compiler.h>
24#include <linux/err.h>
25#include <linux/ioport.h>
26#include <linux/io.h>
27#include <linux/gpio.h>
28#include <linux/clk.h>
29#include <linux/device.h>
30#include <linux/platform_device.h>
31#include <linux/dma-mapping.h>
32#include <linux/dmaengine.h>
33#include <linux/delay.h>
34#include <linux/seq_file.h>
35#include <linux/scatterlist.h>
36#include <linux/interrupt.h>
37#include <linux/spinlock.h>
38#include <linux/debugfs.h>
39#include <linux/pm_runtime.h>
40#include <linux/of_platform.h>
41#include <linux/hsi/hsi.h>
42#include <linux/idr.h>
43
44#include "omap_ssi_regs.h"
45#include "omap_ssi.h"
46
47/* For automatically allocated device IDs */
48static DEFINE_IDA(platform_omap_ssi_ida);
49
50#ifdef CONFIG_DEBUG_FS
51static int ssi_debug_show(struct seq_file *m, void *p __maybe_unused)
52{
53	struct hsi_controller *ssi = m->private;
54	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
55	void __iomem *sys = omap_ssi->sys;
56
57	pm_runtime_get_sync(ssi->device.parent);
58	seq_printf(m, "REVISION\t: 0x%08x\n",  readl(sys + SSI_REVISION_REG));
59	seq_printf(m, "SYSCONFIG\t: 0x%08x\n", readl(sys + SSI_SYSCONFIG_REG));
60	seq_printf(m, "SYSSTATUS\t: 0x%08x\n", readl(sys + SSI_SYSSTATUS_REG));
61	pm_runtime_put_sync(ssi->device.parent);
62
63	return 0;
64}
65
66static int ssi_debug_gdd_show(struct seq_file *m, void *p __maybe_unused)
67{
68	struct hsi_controller *ssi = m->private;
69	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
70	void __iomem *gdd = omap_ssi->gdd;
71	void __iomem *sys = omap_ssi->sys;
72	int lch;
73
74	pm_runtime_get_sync(ssi->device.parent);
75
76	seq_printf(m, "GDD_MPU_STATUS\t: 0x%08x\n",
77		readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG));
78	seq_printf(m, "GDD_MPU_ENABLE\t: 0x%08x\n\n",
79		readl(sys + SSI_GDD_MPU_IRQ_ENABLE_REG));
80	seq_printf(m, "HW_ID\t\t: 0x%08x\n",
81				readl(gdd + SSI_GDD_HW_ID_REG));
82	seq_printf(m, "PPORT_ID\t: 0x%08x\n",
83				readl(gdd + SSI_GDD_PPORT_ID_REG));
84	seq_printf(m, "MPORT_ID\t: 0x%08x\n",
85				readl(gdd + SSI_GDD_MPORT_ID_REG));
86	seq_printf(m, "TEST\t\t: 0x%08x\n",
87				readl(gdd + SSI_GDD_TEST_REG));
88	seq_printf(m, "GCR\t\t: 0x%08x\n",
89				readl(gdd + SSI_GDD_GCR_REG));
90
91	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
92		seq_printf(m, "\nGDD LCH %d\n=========\n", lch);
93		seq_printf(m, "CSDP\t\t: 0x%04x\n",
94				readw(gdd + SSI_GDD_CSDP_REG(lch)));
95		seq_printf(m, "CCR\t\t: 0x%04x\n",
96				readw(gdd + SSI_GDD_CCR_REG(lch)));
97		seq_printf(m, "CICR\t\t: 0x%04x\n",
98				readw(gdd + SSI_GDD_CICR_REG(lch)));
99		seq_printf(m, "CSR\t\t: 0x%04x\n",
100				readw(gdd + SSI_GDD_CSR_REG(lch)));
101		seq_printf(m, "CSSA\t\t: 0x%08x\n",
102				readl(gdd + SSI_GDD_CSSA_REG(lch)));
103		seq_printf(m, "CDSA\t\t: 0x%08x\n",
104				readl(gdd + SSI_GDD_CDSA_REG(lch)));
105		seq_printf(m, "CEN\t\t: 0x%04x\n",
106				readw(gdd + SSI_GDD_CEN_REG(lch)));
107		seq_printf(m, "CSAC\t\t: 0x%04x\n",
108				readw(gdd + SSI_GDD_CSAC_REG(lch)));
109		seq_printf(m, "CDAC\t\t: 0x%04x\n",
110				readw(gdd + SSI_GDD_CDAC_REG(lch)));
111		seq_printf(m, "CLNK_CTRL\t: 0x%04x\n",
112				readw(gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
113	}
114
115	pm_runtime_put_sync(ssi->device.parent);
116
117	return 0;
118}
119
120static int ssi_regs_open(struct inode *inode, struct file *file)
121{
122	return single_open(file, ssi_debug_show, inode->i_private);
123}
124
125static int ssi_gdd_regs_open(struct inode *inode, struct file *file)
126{
127	return single_open(file, ssi_debug_gdd_show, inode->i_private);
128}
129
130static const struct file_operations ssi_regs_fops = {
131	.open		= ssi_regs_open,
132	.read		= seq_read,
133	.llseek		= seq_lseek,
134	.release	= single_release,
135};
136
137static const struct file_operations ssi_gdd_regs_fops = {
138	.open		= ssi_gdd_regs_open,
139	.read		= seq_read,
140	.llseek		= seq_lseek,
141	.release	= single_release,
142};
143
144static int __init ssi_debug_add_ctrl(struct hsi_controller *ssi)
145{
146	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
147	struct dentry *dir;
148
149	/* SSI controller */
150	omap_ssi->dir = debugfs_create_dir(dev_name(&ssi->device), NULL);
151	if (!omap_ssi->dir)
152		return -ENOMEM;
153
154	debugfs_create_file("regs", S_IRUGO, omap_ssi->dir, ssi,
155								&ssi_regs_fops);
156	/* SSI GDD (DMA) */
157	dir = debugfs_create_dir("gdd", omap_ssi->dir);
158	if (!dir)
159		goto rback;
160	debugfs_create_file("regs", S_IRUGO, dir, ssi, &ssi_gdd_regs_fops);
161
162	return 0;
163rback:
164	debugfs_remove_recursive(omap_ssi->dir);
165
166	return -ENOMEM;
167}
168
169static void ssi_debug_remove_ctrl(struct hsi_controller *ssi)
170{
171	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
172
173	debugfs_remove_recursive(omap_ssi->dir);
174}
175#endif /* CONFIG_DEBUG_FS */
176
177/*
178 * FIXME: Horrible HACK needed until we remove the useless wakeline test
179 * in the CMT. To be removed !!!!
180 */
181void ssi_waketest(struct hsi_client *cl, unsigned int enable)
182{
183	struct hsi_port *port = hsi_get_port(cl);
184	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
185	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
186	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
187
188	omap_port->wktest = !!enable;
189	if (omap_port->wktest) {
190		pm_runtime_get_sync(ssi->device.parent);
191		writel_relaxed(SSI_WAKE(0),
192				omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
193	} else {
194		writel_relaxed(SSI_WAKE(0),
195				omap_ssi->sys +	SSI_CLEAR_WAKE_REG(port->num));
196		pm_runtime_put_sync(ssi->device.parent);
197	}
198}
199EXPORT_SYMBOL_GPL(ssi_waketest);
200
201static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
202{
203	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
204	struct hsi_msg *msg = omap_ssi->gdd_trn[lch].msg;
205	struct hsi_port *port = to_hsi_port(msg->cl->device.parent);
206	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
207	unsigned int dir;
208	u32 csr;
209	u32 val;
210
211	spin_lock(&omap_ssi->lock);
212
213	val = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
214	val &= ~SSI_GDD_LCH(lch);
215	writel_relaxed(val, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
216
217	if (msg->ttype == HSI_MSG_READ) {
218		dir = DMA_FROM_DEVICE;
219		val = SSI_DATAAVAILABLE(msg->channel);
220		pm_runtime_put_sync(ssi->device.parent);
221	} else {
222		dir = DMA_TO_DEVICE;
223		val = SSI_DATAACCEPT(msg->channel);
224		/* Keep clocks reference for write pio event */
225	}
226	dma_unmap_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents, dir);
227	csr = readw(omap_ssi->gdd + SSI_GDD_CSR_REG(lch));
228	omap_ssi->gdd_trn[lch].msg = NULL; /* release GDD lch */
229	dev_dbg(&port->device, "DMA completed ch %d ttype %d\n",
230				msg->channel, msg->ttype);
231	spin_unlock(&omap_ssi->lock);
232	if (csr & SSI_CSR_TOUR) { /* Timeout error */
233		msg->status = HSI_STATUS_ERROR;
234		msg->actual_len = 0;
235		spin_lock(&omap_port->lock);
236		list_del(&msg->link); /* Dequeue msg */
237		spin_unlock(&omap_port->lock);
238		msg->complete(msg);
239		return;
240	}
241	spin_lock(&omap_port->lock);
242	val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
243	writel_relaxed(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
244	spin_unlock(&omap_port->lock);
245
246	msg->status = HSI_STATUS_COMPLETED;
247	msg->actual_len = sg_dma_len(msg->sgt.sgl);
248}
249
250static void ssi_gdd_tasklet(unsigned long dev)
251{
252	struct hsi_controller *ssi = (struct hsi_controller *)dev;
253	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
254	void __iomem *sys = omap_ssi->sys;
255	unsigned int lch;
256	u32 status_reg;
257
258	pm_runtime_get_sync(ssi->device.parent);
259
260	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
261	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
262		if (status_reg & SSI_GDD_LCH(lch))
263			ssi_gdd_complete(ssi, lch);
264	}
265	writel_relaxed(status_reg, sys + SSI_GDD_MPU_IRQ_STATUS_REG);
266	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
267
268	pm_runtime_put_sync(ssi->device.parent);
269
270	if (status_reg)
271		tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
272	else
273		enable_irq(omap_ssi->gdd_irq);
274
275}
276
277static irqreturn_t ssi_gdd_isr(int irq, void *ssi)
278{
279	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
280
281	tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
282	disable_irq_nosync(irq);
283
284	return IRQ_HANDLED;
285}
286
287static unsigned long ssi_get_clk_rate(struct hsi_controller *ssi)
288{
289	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
290	unsigned long rate = clk_get_rate(omap_ssi->fck);
291	return rate;
292}
293
294static int __init ssi_get_iomem(struct platform_device *pd,
295		const char *name, void __iomem **pbase, dma_addr_t *phy)
296{
297	struct resource *mem;
298	void __iomem *base;
299	struct hsi_controller *ssi = platform_get_drvdata(pd);
300
301	mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
302	base = devm_ioremap_resource(&ssi->device, mem);
303	if (IS_ERR(base))
304		return PTR_ERR(base);
305
306	*pbase = base;
307
308	if (phy)
309		*phy = mem->start;
310
311	return 0;
312}
313
314static int __init ssi_add_controller(struct hsi_controller *ssi,
315						struct platform_device *pd)
316{
317	struct omap_ssi_controller *omap_ssi;
318	int err;
319
320	omap_ssi = devm_kzalloc(&ssi->device, sizeof(*omap_ssi), GFP_KERNEL);
321	if (!omap_ssi) {
322		dev_err(&pd->dev, "not enough memory for omap ssi\n");
323		return -ENOMEM;
324	}
325
326	ssi->id = ida_simple_get(&platform_omap_ssi_ida, 0, 0, GFP_KERNEL);
327	if (ssi->id < 0) {
328		err = ssi->id;
329		goto out_err;
330	}
331
332	ssi->owner = THIS_MODULE;
333	ssi->device.parent = &pd->dev;
334	dev_set_name(&ssi->device, "ssi%d", ssi->id);
335	hsi_controller_set_drvdata(ssi, omap_ssi);
336	omap_ssi->dev = &ssi->device;
337	err = ssi_get_iomem(pd, "sys", &omap_ssi->sys, NULL);
338	if (err < 0)
339		goto out_err;
340	err = ssi_get_iomem(pd, "gdd", &omap_ssi->gdd, NULL);
341	if (err < 0)
342		goto out_err;
343	err = platform_get_irq_byname(pd, "gdd_mpu");
344	if (err < 0) {
345		dev_err(&pd->dev, "GDD IRQ resource missing\n");
346		goto out_err;
347	}
348	omap_ssi->gdd_irq = err;
349	tasklet_init(&omap_ssi->gdd_tasklet, ssi_gdd_tasklet,
350							(unsigned long)ssi);
351	err = devm_request_irq(&ssi->device, omap_ssi->gdd_irq, ssi_gdd_isr,
352						0, "gdd_mpu", ssi);
353	if (err < 0) {
354		dev_err(&ssi->device, "Request GDD IRQ %d failed (%d)",
355							omap_ssi->gdd_irq, err);
356		goto out_err;
357	}
358
359	omap_ssi->port = devm_kzalloc(&ssi->device,
360		sizeof(struct omap_ssi_port *) * ssi->num_ports, GFP_KERNEL);
361	if (!omap_ssi->port) {
362		err = -ENOMEM;
363		goto out_err;
364	}
365
366	omap_ssi->fck = devm_clk_get(&ssi->device, "ssi_ssr_fck");
367	if (IS_ERR(omap_ssi->fck)) {
368		dev_err(&pd->dev, "Could not acquire clock \"ssi_ssr_fck\": %li\n",
369			PTR_ERR(omap_ssi->fck));
370		err = -ENODEV;
371		goto out_err;
372	}
373
374	/* TODO: find register, which can be used to detect context loss */
375	omap_ssi->get_loss = NULL;
376
377	omap_ssi->max_speed = UINT_MAX;
378	spin_lock_init(&omap_ssi->lock);
379	err = hsi_register_controller(ssi);
380
381	if (err < 0)
382		goto out_err;
383
384	return 0;
385
386out_err:
387	ida_simple_remove(&platform_omap_ssi_ida, ssi->id);
388	return err;
389}
390
391static int __init ssi_hw_init(struct hsi_controller *ssi)
392{
393	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
394	unsigned int i;
395	u32 val;
396	int err;
397
398	err = pm_runtime_get_sync(ssi->device.parent);
399	if (err < 0) {
400		dev_err(&ssi->device, "runtime PM failed %d\n", err);
401		return err;
402	}
403	/* Reseting SSI controller */
404	writel_relaxed(SSI_SOFTRESET, omap_ssi->sys + SSI_SYSCONFIG_REG);
405	val = readl(omap_ssi->sys + SSI_SYSSTATUS_REG);
406	for (i = 0; ((i < 20) && !(val & SSI_RESETDONE)); i++) {
407		msleep(20);
408		val = readl(omap_ssi->sys + SSI_SYSSTATUS_REG);
409	}
410	if (!(val & SSI_RESETDONE)) {
411		dev_err(&ssi->device, "SSI HW reset failed\n");
412		pm_runtime_put_sync(ssi->device.parent);
413		return -EIO;
414	}
415	/* Reseting GDD */
416	writel_relaxed(SSI_SWRESET, omap_ssi->gdd + SSI_GDD_GRST_REG);
417	/* Get FCK rate in KHz */
418	omap_ssi->fck_rate = DIV_ROUND_CLOSEST(ssi_get_clk_rate(ssi), 1000);
419	dev_dbg(&ssi->device, "SSI fck rate %lu KHz\n", omap_ssi->fck_rate);
420	/* Set default PM settings */
421	val = SSI_AUTOIDLE | SSI_SIDLEMODE_SMART | SSI_MIDLEMODE_SMART;
422	writel_relaxed(val, omap_ssi->sys + SSI_SYSCONFIG_REG);
423	omap_ssi->sysconfig = val;
424	writel_relaxed(SSI_CLK_AUTOGATING_ON, omap_ssi->sys + SSI_GDD_GCR_REG);
425	omap_ssi->gdd_gcr = SSI_CLK_AUTOGATING_ON;
426	pm_runtime_put_sync(ssi->device.parent);
427
428	return 0;
429}
430
431static void ssi_remove_controller(struct hsi_controller *ssi)
432{
433	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
434	int id = ssi->id;
435	tasklet_kill(&omap_ssi->gdd_tasklet);
436	hsi_unregister_controller(ssi);
437	ida_simple_remove(&platform_omap_ssi_ida, id);
438}
439
440static inline int ssi_of_get_available_ports_count(const struct device_node *np)
441{
442	struct device_node *child;
443	int num = 0;
444
445	for_each_available_child_of_node(np, child)
446		if (of_device_is_compatible(child, "ti,omap3-ssi-port"))
447			num++;
448
449	return num;
450}
451
452static int ssi_remove_ports(struct device *dev, void *c)
453{
454	struct platform_device *pdev = to_platform_device(dev);
455
456	of_device_unregister(pdev);
457
458	return 0;
459}
460
461static int __init ssi_probe(struct platform_device *pd)
462{
463	struct platform_device *childpdev;
464	struct device_node *np = pd->dev.of_node;
465	struct device_node *child;
466	struct hsi_controller *ssi;
467	int err;
468	int num_ports;
469
470	if (!np) {
471		dev_err(&pd->dev, "missing device tree data\n");
472		return -EINVAL;
473	}
474
475	num_ports = ssi_of_get_available_ports_count(np);
476
477	ssi = hsi_alloc_controller(num_ports, GFP_KERNEL);
478	if (!ssi) {
479		dev_err(&pd->dev, "No memory for controller\n");
480		return -ENOMEM;
481	}
482
483	platform_set_drvdata(pd, ssi);
484
485	err = ssi_add_controller(ssi, pd);
486	if (err < 0)
487		goto out1;
488
489	pm_runtime_irq_safe(&pd->dev);
490	pm_runtime_enable(&pd->dev);
491
492	err = ssi_hw_init(ssi);
493	if (err < 0)
494		goto out2;
495#ifdef CONFIG_DEBUG_FS
496	err = ssi_debug_add_ctrl(ssi);
497	if (err < 0)
498		goto out2;
499#endif
500
501	for_each_available_child_of_node(np, child) {
502		if (!of_device_is_compatible(child, "ti,omap3-ssi-port"))
503			continue;
504
505		childpdev = of_platform_device_create(child, NULL, &pd->dev);
506		if (!childpdev) {
507			err = -ENODEV;
508			dev_err(&pd->dev, "failed to create ssi controller port\n");
509			goto out3;
510		}
511	}
512
513	dev_info(&pd->dev, "ssi controller %d initialized (%d ports)!\n",
514		ssi->id, num_ports);
515	return err;
516out3:
517	device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
518out2:
519	ssi_remove_controller(ssi);
520out1:
521	platform_set_drvdata(pd, NULL);
522	pm_runtime_disable(&pd->dev);
523
524	return err;
525}
526
527static int __exit ssi_remove(struct platform_device *pd)
528{
529	struct hsi_controller *ssi = platform_get_drvdata(pd);
530
531#ifdef CONFIG_DEBUG_FS
532	ssi_debug_remove_ctrl(ssi);
533#endif
534	ssi_remove_controller(ssi);
535	platform_set_drvdata(pd, NULL);
536
537	pm_runtime_disable(&pd->dev);
538
539	/* cleanup of of_platform_populate() call */
540	device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
541
542	return 0;
543}
544
545#ifdef CONFIG_PM
546static int omap_ssi_runtime_suspend(struct device *dev)
547{
548	struct hsi_controller *ssi = dev_get_drvdata(dev);
549	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
550
551	dev_dbg(dev, "runtime suspend!\n");
552
553	if (omap_ssi->get_loss)
554		omap_ssi->loss_count =
555				omap_ssi->get_loss(ssi->device.parent);
556
557	return 0;
558}
559
560static int omap_ssi_runtime_resume(struct device *dev)
561{
562	struct hsi_controller *ssi = dev_get_drvdata(dev);
563	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
564
565	dev_dbg(dev, "runtime resume!\n");
566
567	if ((omap_ssi->get_loss) && (omap_ssi->loss_count ==
568				omap_ssi->get_loss(ssi->device.parent)))
569		return 0;
570
571	writel_relaxed(omap_ssi->gdd_gcr, omap_ssi->gdd + SSI_GDD_GCR_REG);
572
573	return 0;
574}
575
576static const struct dev_pm_ops omap_ssi_pm_ops = {
577	SET_RUNTIME_PM_OPS(omap_ssi_runtime_suspend, omap_ssi_runtime_resume,
578		NULL)
579};
580
581#define DEV_PM_OPS     (&omap_ssi_pm_ops)
582#else
583#define DEV_PM_OPS     NULL
584#endif
585
586#ifdef CONFIG_OF
587static const struct of_device_id omap_ssi_of_match[] = {
588	{ .compatible = "ti,omap3-ssi", },
589	{},
590};
591MODULE_DEVICE_TABLE(of, omap_ssi_of_match);
592#else
593#define omap_ssi_of_match NULL
594#endif
595
596static struct platform_driver ssi_pdriver = {
597	.remove	= __exit_p(ssi_remove),
598	.driver	= {
599		.name	= "omap_ssi",
600		.pm     = DEV_PM_OPS,
601		.of_match_table = omap_ssi_of_match,
602	},
603};
604
605module_platform_driver_probe(ssi_pdriver, ssi_probe);
606
607MODULE_ALIAS("platform:omap_ssi");
608MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
609MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
610MODULE_DESCRIPTION("Synchronous Serial Interface Driver");
611MODULE_LICENSE("GPL v2");
612