1// SPDX-License-Identifier: GPL-2.0-only
2/* OMAP SSI driver.
3 *
4 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
5 * Copyright (C) 2014 Sebastian Reichel <sre@kernel.org>
6 *
7 * Contact: Carlos Chinea <carlos.chinea@nokia.com>
8 */
9
10#include <linux/compiler.h>
11#include <linux/err.h>
12#include <linux/ioport.h>
13#include <linux/io.h>
14#include <linux/clk.h>
15#include <linux/device.h>
16#include <linux/platform_device.h>
17#include <linux/dma-mapping.h>
18#include <linux/dmaengine.h>
19#include <linux/delay.h>
20#include <linux/hsi/ssi_protocol.h>
21#include <linux/seq_file.h>
22#include <linux/scatterlist.h>
23#include <linux/interrupt.h>
24#include <linux/spinlock.h>
25#include <linux/debugfs.h>
26#include <linux/pinctrl/consumer.h>
27#include <linux/pm_runtime.h>
28#include <linux/of.h>
29#include <linux/of_platform.h>
30#include <linux/hsi/hsi.h>
31#include <linux/idr.h>
32
33#include "omap_ssi_regs.h"
34#include "omap_ssi.h"
35
36/* For automatically allocated device IDs */
37static DEFINE_IDA(platform_omap_ssi_ida);
38
39#ifdef CONFIG_DEBUG_FS
40static int ssi_regs_show(struct seq_file *m, void *p __maybe_unused)
41{
42	struct hsi_controller *ssi = m->private;
43	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
44	void __iomem *sys = omap_ssi->sys;
45
46	pm_runtime_get_sync(ssi->device.parent);
47	seq_printf(m, "REVISION\t: 0x%08x\n",  readl(sys + SSI_REVISION_REG));
48	seq_printf(m, "SYSCONFIG\t: 0x%08x\n", readl(sys + SSI_SYSCONFIG_REG));
49	seq_printf(m, "SYSSTATUS\t: 0x%08x\n", readl(sys + SSI_SYSSTATUS_REG));
50	pm_runtime_put(ssi->device.parent);
51
52	return 0;
53}
54
55static int ssi_gdd_regs_show(struct seq_file *m, void *p __maybe_unused)
56{
57	struct hsi_controller *ssi = m->private;
58	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
59	void __iomem *gdd = omap_ssi->gdd;
60	void __iomem *sys = omap_ssi->sys;
61	int lch;
62
63	pm_runtime_get_sync(ssi->device.parent);
64
65	seq_printf(m, "GDD_MPU_STATUS\t: 0x%08x\n",
66		readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG));
67	seq_printf(m, "GDD_MPU_ENABLE\t: 0x%08x\n\n",
68		readl(sys + SSI_GDD_MPU_IRQ_ENABLE_REG));
69	seq_printf(m, "HW_ID\t\t: 0x%08x\n",
70				readl(gdd + SSI_GDD_HW_ID_REG));
71	seq_printf(m, "PPORT_ID\t: 0x%08x\n",
72				readl(gdd + SSI_GDD_PPORT_ID_REG));
73	seq_printf(m, "MPORT_ID\t: 0x%08x\n",
74				readl(gdd + SSI_GDD_MPORT_ID_REG));
75	seq_printf(m, "TEST\t\t: 0x%08x\n",
76				readl(gdd + SSI_GDD_TEST_REG));
77	seq_printf(m, "GCR\t\t: 0x%08x\n",
78				readl(gdd + SSI_GDD_GCR_REG));
79
80	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
81		seq_printf(m, "\nGDD LCH %d\n=========\n", lch);
82		seq_printf(m, "CSDP\t\t: 0x%04x\n",
83				readw(gdd + SSI_GDD_CSDP_REG(lch)));
84		seq_printf(m, "CCR\t\t: 0x%04x\n",
85				readw(gdd + SSI_GDD_CCR_REG(lch)));
86		seq_printf(m, "CICR\t\t: 0x%04x\n",
87				readw(gdd + SSI_GDD_CICR_REG(lch)));
88		seq_printf(m, "CSR\t\t: 0x%04x\n",
89				readw(gdd + SSI_GDD_CSR_REG(lch)));
90		seq_printf(m, "CSSA\t\t: 0x%08x\n",
91				readl(gdd + SSI_GDD_CSSA_REG(lch)));
92		seq_printf(m, "CDSA\t\t: 0x%08x\n",
93				readl(gdd + SSI_GDD_CDSA_REG(lch)));
94		seq_printf(m, "CEN\t\t: 0x%04x\n",
95				readw(gdd + SSI_GDD_CEN_REG(lch)));
96		seq_printf(m, "CSAC\t\t: 0x%04x\n",
97				readw(gdd + SSI_GDD_CSAC_REG(lch)));
98		seq_printf(m, "CDAC\t\t: 0x%04x\n",
99				readw(gdd + SSI_GDD_CDAC_REG(lch)));
100		seq_printf(m, "CLNK_CTRL\t: 0x%04x\n",
101				readw(gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
102	}
103
104	pm_runtime_put(ssi->device.parent);
105
106	return 0;
107}
108
109DEFINE_SHOW_ATTRIBUTE(ssi_regs);
110DEFINE_SHOW_ATTRIBUTE(ssi_gdd_regs);
111
112static int ssi_debug_add_ctrl(struct hsi_controller *ssi)
113{
114	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
115	struct dentry *dir;
116
117	/* SSI controller */
118	omap_ssi->dir = debugfs_create_dir(dev_name(&ssi->device), NULL);
119	if (!omap_ssi->dir)
120		return -ENOMEM;
121
122	debugfs_create_file("regs", S_IRUGO, omap_ssi->dir, ssi,
123								&ssi_regs_fops);
124	/* SSI GDD (DMA) */
125	dir = debugfs_create_dir("gdd", omap_ssi->dir);
126	if (!dir)
127		goto rback;
128	debugfs_create_file("regs", S_IRUGO, dir, ssi, &ssi_gdd_regs_fops);
129
130	return 0;
131rback:
132	debugfs_remove_recursive(omap_ssi->dir);
133
134	return -ENOMEM;
135}
136
137static void ssi_debug_remove_ctrl(struct hsi_controller *ssi)
138{
139	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
140
141	debugfs_remove_recursive(omap_ssi->dir);
142}
143#endif /* CONFIG_DEBUG_FS */
144
145/*
146 * FIXME: Horrible HACK needed until we remove the useless wakeline test
147 * in the CMT. To be removed !!!!
148 */
149void ssi_waketest(struct hsi_client *cl, unsigned int enable)
150{
151	struct hsi_port *port = hsi_get_port(cl);
152	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
153	struct hsi_controller *ssi = to_hsi_controller(port->device.parent);
154	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
155
156	omap_port->wktest = !!enable;
157	if (omap_port->wktest) {
158		pm_runtime_get_sync(ssi->device.parent);
159		writel_relaxed(SSI_WAKE(0),
160				omap_ssi->sys + SSI_SET_WAKE_REG(port->num));
161	} else {
162		writel_relaxed(SSI_WAKE(0),
163				omap_ssi->sys +	SSI_CLEAR_WAKE_REG(port->num));
164		pm_runtime_put(ssi->device.parent);
165	}
166}
167EXPORT_SYMBOL_GPL(ssi_waketest);
168
169static void ssi_gdd_complete(struct hsi_controller *ssi, unsigned int lch)
170{
171	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
172	struct hsi_msg *msg = omap_ssi->gdd_trn[lch].msg;
173	struct hsi_port *port = to_hsi_port(msg->cl->device.parent);
174	struct omap_ssi_port *omap_port = hsi_port_drvdata(port);
175	unsigned int dir;
176	u32 csr;
177	u32 val;
178
179	spin_lock(&omap_ssi->lock);
180
181	val = readl(omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
182	val &= ~SSI_GDD_LCH(lch);
183	writel_relaxed(val, omap_ssi->sys + SSI_GDD_MPU_IRQ_ENABLE_REG);
184
185	if (msg->ttype == HSI_MSG_READ) {
186		dir = DMA_FROM_DEVICE;
187		val = SSI_DATAAVAILABLE(msg->channel);
188		pm_runtime_put(omap_port->pdev);
189	} else {
190		dir = DMA_TO_DEVICE;
191		val = SSI_DATAACCEPT(msg->channel);
192		/* Keep clocks reference for write pio event */
193	}
194	dma_unmap_sg(&ssi->device, msg->sgt.sgl, msg->sgt.nents, dir);
195	csr = readw(omap_ssi->gdd + SSI_GDD_CSR_REG(lch));
196	omap_ssi->gdd_trn[lch].msg = NULL; /* release GDD lch */
197	dev_dbg(&port->device, "DMA completed ch %d ttype %d\n",
198				msg->channel, msg->ttype);
199	spin_unlock(&omap_ssi->lock);
200	if (csr & SSI_CSR_TOUR) { /* Timeout error */
201		msg->status = HSI_STATUS_ERROR;
202		msg->actual_len = 0;
203		spin_lock(&omap_port->lock);
204		list_del(&msg->link); /* Dequeue msg */
205		spin_unlock(&omap_port->lock);
206
207		list_add_tail(&msg->link, &omap_port->errqueue);
208		schedule_delayed_work(&omap_port->errqueue_work, 0);
209		return;
210	}
211	spin_lock(&omap_port->lock);
212	val |= readl(omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
213	writel_relaxed(val, omap_ssi->sys + SSI_MPU_ENABLE_REG(port->num, 0));
214	spin_unlock(&omap_port->lock);
215
216	msg->status = HSI_STATUS_COMPLETED;
217	msg->actual_len = sg_dma_len(msg->sgt.sgl);
218}
219
220static void ssi_gdd_tasklet(unsigned long dev)
221{
222	struct hsi_controller *ssi = (struct hsi_controller *)dev;
223	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
224	void __iomem *sys = omap_ssi->sys;
225	unsigned int lch;
226	u32 status_reg;
227
228	pm_runtime_get(ssi->device.parent);
229
230	if (!pm_runtime_active(ssi->device.parent)) {
231		dev_warn(ssi->device.parent, "ssi_gdd_tasklet called without runtime PM!\n");
232		pm_runtime_put(ssi->device.parent);
233		return;
234	}
235
236	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
237	for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
238		if (status_reg & SSI_GDD_LCH(lch))
239			ssi_gdd_complete(ssi, lch);
240	}
241	writel_relaxed(status_reg, sys + SSI_GDD_MPU_IRQ_STATUS_REG);
242	status_reg = readl(sys + SSI_GDD_MPU_IRQ_STATUS_REG);
243
244	pm_runtime_put(ssi->device.parent);
245
246	if (status_reg)
247		tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
248	else
249		enable_irq(omap_ssi->gdd_irq);
250
251}
252
253static irqreturn_t ssi_gdd_isr(int irq, void *ssi)
254{
255	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
256
257	tasklet_hi_schedule(&omap_ssi->gdd_tasklet);
258	disable_irq_nosync(irq);
259
260	return IRQ_HANDLED;
261}
262
263static unsigned long ssi_get_clk_rate(struct hsi_controller *ssi)
264{
265	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
266	unsigned long rate = clk_get_rate(omap_ssi->fck);
267	return rate;
268}
269
270static int ssi_clk_event(struct notifier_block *nb, unsigned long event,
271								void *data)
272{
273	struct omap_ssi_controller *omap_ssi = container_of(nb,
274					struct omap_ssi_controller, fck_nb);
275	struct hsi_controller *ssi = to_hsi_controller(omap_ssi->dev);
276	struct clk_notifier_data *clk_data = data;
277	struct omap_ssi_port *omap_port;
278	int i;
279
280	switch (event) {
281	case PRE_RATE_CHANGE:
282		dev_dbg(&ssi->device, "pre rate change\n");
283
284		for (i = 0; i < ssi->num_ports; i++) {
285			omap_port = omap_ssi->port[i];
286
287			if (!omap_port)
288				continue;
289
290			/* Workaround for SWBREAK + CAwake down race in CMT */
291			disable_irq(omap_port->wake_irq);
292
293			/* stop all ssi communication */
294			pinctrl_pm_select_idle_state(omap_port->pdev);
295			udelay(1); /* wait for racing frames */
296		}
297
298		break;
299	case ABORT_RATE_CHANGE:
300		dev_dbg(&ssi->device, "abort rate change\n");
301		fallthrough;
302	case POST_RATE_CHANGE:
303		dev_dbg(&ssi->device, "post rate change (%lu -> %lu)\n",
304			clk_data->old_rate, clk_data->new_rate);
305		omap_ssi->fck_rate = DIV_ROUND_CLOSEST(clk_data->new_rate, 1000); /* kHz */
306
307		for (i = 0; i < ssi->num_ports; i++) {
308			omap_port = omap_ssi->port[i];
309
310			if (!omap_port)
311				continue;
312
313			omap_ssi_port_update_fclk(ssi, omap_port);
314
315			/* resume ssi communication */
316			pinctrl_pm_select_default_state(omap_port->pdev);
317			enable_irq(omap_port->wake_irq);
318		}
319
320		break;
321	default:
322		break;
323	}
324
325	return NOTIFY_DONE;
326}
327
328static int ssi_get_iomem(struct platform_device *pd,
329		const char *name, void __iomem **pbase, dma_addr_t *phy)
330{
331	struct resource *mem;
332	void __iomem *base;
333	struct hsi_controller *ssi = platform_get_drvdata(pd);
334
335	mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
336	base = devm_ioremap_resource(&ssi->device, mem);
337	if (IS_ERR(base))
338		return PTR_ERR(base);
339
340	*pbase = base;
341
342	if (phy)
343		*phy = mem->start;
344
345	return 0;
346}
347
348static int ssi_add_controller(struct hsi_controller *ssi,
349						struct platform_device *pd)
350{
351	struct omap_ssi_controller *omap_ssi;
352	int err;
353
354	omap_ssi = devm_kzalloc(&ssi->device, sizeof(*omap_ssi), GFP_KERNEL);
355	if (!omap_ssi)
356		return -ENOMEM;
357
358	err = ida_alloc(&platform_omap_ssi_ida, GFP_KERNEL);
359	if (err < 0)
360		return err;
361	ssi->id = err;
362
363	ssi->owner = THIS_MODULE;
364	ssi->device.parent = &pd->dev;
365	dev_set_name(&ssi->device, "ssi%d", ssi->id);
366	hsi_controller_set_drvdata(ssi, omap_ssi);
367	omap_ssi->dev = &ssi->device;
368	err = ssi_get_iomem(pd, "sys", &omap_ssi->sys, NULL);
369	if (err < 0)
370		goto out_err;
371	err = ssi_get_iomem(pd, "gdd", &omap_ssi->gdd, NULL);
372	if (err < 0)
373		goto out_err;
374	err = platform_get_irq_byname(pd, "gdd_mpu");
375	if (err < 0)
376		goto out_err;
377	omap_ssi->gdd_irq = err;
378	tasklet_init(&omap_ssi->gdd_tasklet, ssi_gdd_tasklet,
379							(unsigned long)ssi);
380	err = devm_request_irq(&ssi->device, omap_ssi->gdd_irq, ssi_gdd_isr,
381						0, "gdd_mpu", ssi);
382	if (err < 0) {
383		dev_err(&ssi->device, "Request GDD IRQ %d failed (%d)",
384							omap_ssi->gdd_irq, err);
385		goto out_err;
386	}
387
388	omap_ssi->port = devm_kcalloc(&ssi->device, ssi->num_ports,
389				      sizeof(*omap_ssi->port), GFP_KERNEL);
390	if (!omap_ssi->port) {
391		err = -ENOMEM;
392		goto out_err;
393	}
394
395	omap_ssi->fck = devm_clk_get(&ssi->device, "ssi_ssr_fck");
396	if (IS_ERR(omap_ssi->fck)) {
397		dev_err(&pd->dev, "Could not acquire clock \"ssi_ssr_fck\": %li\n",
398			PTR_ERR(omap_ssi->fck));
399		err = -ENODEV;
400		goto out_err;
401	}
402
403	omap_ssi->fck_nb.notifier_call = ssi_clk_event;
404	omap_ssi->fck_nb.priority = INT_MAX;
405	clk_notifier_register(omap_ssi->fck, &omap_ssi->fck_nb);
406
407	/* TODO: find register, which can be used to detect context loss */
408	omap_ssi->get_loss = NULL;
409
410	omap_ssi->max_speed = UINT_MAX;
411	spin_lock_init(&omap_ssi->lock);
412	err = hsi_register_controller(ssi);
413
414	if (err < 0)
415		goto out_err;
416
417	return 0;
418
419out_err:
420	ida_free(&platform_omap_ssi_ida, ssi->id);
421	return err;
422}
423
424static int ssi_hw_init(struct hsi_controller *ssi)
425{
426	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
427	int err;
428
429	err = pm_runtime_resume_and_get(ssi->device.parent);
430	if (err < 0) {
431		dev_err(&ssi->device, "runtime PM failed %d\n", err);
432		return err;
433	}
434	/* Resetting GDD */
435	writel_relaxed(SSI_SWRESET, omap_ssi->gdd + SSI_GDD_GRST_REG);
436	/* Get FCK rate in kHz */
437	omap_ssi->fck_rate = DIV_ROUND_CLOSEST(ssi_get_clk_rate(ssi), 1000);
438	dev_dbg(&ssi->device, "SSI fck rate %lu kHz\n", omap_ssi->fck_rate);
439
440	writel_relaxed(SSI_CLK_AUTOGATING_ON, omap_ssi->sys + SSI_GDD_GCR_REG);
441	omap_ssi->gdd_gcr = SSI_CLK_AUTOGATING_ON;
442	pm_runtime_put_sync(ssi->device.parent);
443
444	return 0;
445}
446
447static void ssi_remove_controller(struct hsi_controller *ssi)
448{
449	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
450	int id = ssi->id;
451	tasklet_kill(&omap_ssi->gdd_tasklet);
452	hsi_unregister_controller(ssi);
453	clk_notifier_unregister(omap_ssi->fck, &omap_ssi->fck_nb);
454	ida_free(&platform_omap_ssi_ida, id);
455}
456
457static inline int ssi_of_get_available_ports_count(const struct device_node *np)
458{
459	struct device_node *child;
460	int num = 0;
461
462	for_each_available_child_of_node(np, child)
463		if (of_device_is_compatible(child, "ti,omap3-ssi-port"))
464			num++;
465
466	return num;
467}
468
469static int ssi_remove_ports(struct device *dev, void *c)
470{
471	struct platform_device *pdev = to_platform_device(dev);
472
473	if (!dev->of_node)
474		return 0;
475
476	of_node_clear_flag(dev->of_node, OF_POPULATED);
477	of_device_unregister(pdev);
478
479	return 0;
480}
481
482static int ssi_probe(struct platform_device *pd)
483{
484	struct platform_device *childpdev;
485	struct device_node *np = pd->dev.of_node;
486	struct device_node *child;
487	struct hsi_controller *ssi;
488	int err;
489	int num_ports;
490
491	if (!np) {
492		dev_err(&pd->dev, "missing device tree data\n");
493		return -EINVAL;
494	}
495
496	num_ports = ssi_of_get_available_ports_count(np);
497
498	ssi = hsi_alloc_controller(num_ports, GFP_KERNEL);
499	if (!ssi) {
500		dev_err(&pd->dev, "No memory for controller\n");
501		return -ENOMEM;
502	}
503
504	platform_set_drvdata(pd, ssi);
505
506	err = ssi_add_controller(ssi, pd);
507	if (err < 0) {
508		hsi_put_controller(ssi);
509		goto out1;
510	}
511
512	pm_runtime_enable(&pd->dev);
513
514	err = ssi_hw_init(ssi);
515	if (err < 0)
516		goto out2;
517#ifdef CONFIG_DEBUG_FS
518	err = ssi_debug_add_ctrl(ssi);
519	if (err < 0)
520		goto out2;
521#endif
522
523	for_each_available_child_of_node(np, child) {
524		if (!of_device_is_compatible(child, "ti,omap3-ssi-port"))
525			continue;
526
527		childpdev = of_platform_device_create(child, NULL, &pd->dev);
528		if (!childpdev) {
529			err = -ENODEV;
530			dev_err(&pd->dev, "failed to create ssi controller port\n");
531			of_node_put(child);
532			goto out3;
533		}
534	}
535
536	dev_info(&pd->dev, "ssi controller %d initialized (%d ports)!\n",
537		ssi->id, num_ports);
538	return err;
539out3:
540	device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
541out2:
542	ssi_remove_controller(ssi);
543	pm_runtime_disable(&pd->dev);
544out1:
545	platform_set_drvdata(pd, NULL);
546
547	return err;
548}
549
550static int ssi_remove(struct platform_device *pd)
551{
552	struct hsi_controller *ssi = platform_get_drvdata(pd);
553
554	/* cleanup of of_platform_populate() call */
555	device_for_each_child(&pd->dev, NULL, ssi_remove_ports);
556
557#ifdef CONFIG_DEBUG_FS
558	ssi_debug_remove_ctrl(ssi);
559#endif
560	ssi_remove_controller(ssi);
561	platform_set_drvdata(pd, NULL);
562
563	pm_runtime_disable(&pd->dev);
564
565	return 0;
566}
567
568#ifdef CONFIG_PM
569static int omap_ssi_runtime_suspend(struct device *dev)
570{
571	struct hsi_controller *ssi = dev_get_drvdata(dev);
572	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
573
574	dev_dbg(dev, "runtime suspend!\n");
575
576	if (omap_ssi->get_loss)
577		omap_ssi->loss_count =
578				omap_ssi->get_loss(ssi->device.parent);
579
580	return 0;
581}
582
583static int omap_ssi_runtime_resume(struct device *dev)
584{
585	struct hsi_controller *ssi = dev_get_drvdata(dev);
586	struct omap_ssi_controller *omap_ssi = hsi_controller_drvdata(ssi);
587
588	dev_dbg(dev, "runtime resume!\n");
589
590	if ((omap_ssi->get_loss) && (omap_ssi->loss_count ==
591				omap_ssi->get_loss(ssi->device.parent)))
592		return 0;
593
594	writel_relaxed(omap_ssi->gdd_gcr, omap_ssi->gdd + SSI_GDD_GCR_REG);
595
596	return 0;
597}
598
599static const struct dev_pm_ops omap_ssi_pm_ops = {
600	SET_RUNTIME_PM_OPS(omap_ssi_runtime_suspend, omap_ssi_runtime_resume,
601		NULL)
602};
603
604#define DEV_PM_OPS     (&omap_ssi_pm_ops)
605#else
606#define DEV_PM_OPS     NULL
607#endif
608
609#ifdef CONFIG_OF
610static const struct of_device_id omap_ssi_of_match[] = {
611	{ .compatible = "ti,omap3-ssi", },
612	{},
613};
614MODULE_DEVICE_TABLE(of, omap_ssi_of_match);
615#else
616#define omap_ssi_of_match NULL
617#endif
618
619static struct platform_driver ssi_pdriver = {
620	.probe = ssi_probe,
621	.remove	= ssi_remove,
622	.driver	= {
623		.name	= "omap_ssi",
624		.pm     = DEV_PM_OPS,
625		.of_match_table = omap_ssi_of_match,
626	},
627};
628
629static int __init ssi_init(void) {
630	int ret;
631
632	ret = platform_driver_register(&ssi_pdriver);
633	if (ret)
634		return ret;
635
636	ret = platform_driver_register(&ssi_port_pdriver);
637	if (ret) {
638		platform_driver_unregister(&ssi_pdriver);
639		return ret;
640	}
641
642	return 0;
643}
644module_init(ssi_init);
645
646static void __exit ssi_exit(void) {
647	platform_driver_unregister(&ssi_port_pdriver);
648	platform_driver_unregister(&ssi_pdriver);
649}
650module_exit(ssi_exit);
651
652MODULE_ALIAS("platform:omap_ssi");
653MODULE_AUTHOR("Carlos Chinea <carlos.chinea@nokia.com>");
654MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
655MODULE_DESCRIPTION("Synchronous Serial Interface Driver");
656MODULE_LICENSE("GPL v2");
657