omap_ssi_core.c

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