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(hsi: ssi);
44 void __iomem *sys = omap_ssi->sys;
45
46 pm_runtime_get_sync(dev: ssi->device.parent);
47 seq_printf(m, fmt: "REVISION\t: 0x%08x\n", readl(addr: sys + SSI_REVISION_REG));
48 seq_printf(m, fmt: "SYSCONFIG\t: 0x%08x\n", readl(addr: sys + SSI_SYSCONFIG_REG));
49 seq_printf(m, fmt: "SYSSTATUS\t: 0x%08x\n", readl(addr: sys + SSI_SYSSTATUS_REG));
50 pm_runtime_put(dev: 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(hsi: ssi);
59 void __iomem *gdd = omap_ssi->gdd;
60 void __iomem *sys = omap_ssi->sys;
61 int lch;
62
63 pm_runtime_get_sync(dev: ssi->device.parent);
64
65 seq_printf(m, fmt: "GDD_MPU_STATUS\t: 0x%08x\n",
66 readl(addr: sys + SSI_GDD_MPU_IRQ_STATUS_REG));
67 seq_printf(m, fmt: "GDD_MPU_ENABLE\t: 0x%08x\n\n",
68 readl(addr: sys + SSI_GDD_MPU_IRQ_ENABLE_REG));
69 seq_printf(m, fmt: "HW_ID\t\t: 0x%08x\n",
70 readl(addr: gdd + SSI_GDD_HW_ID_REG));
71 seq_printf(m, fmt: "PPORT_ID\t: 0x%08x\n",
72 readl(addr: gdd + SSI_GDD_PPORT_ID_REG));
73 seq_printf(m, fmt: "MPORT_ID\t: 0x%08x\n",
74 readl(addr: gdd + SSI_GDD_MPORT_ID_REG));
75 seq_printf(m, fmt: "TEST\t\t: 0x%08x\n",
76 readl(addr: gdd + SSI_GDD_TEST_REG));
77 seq_printf(m, fmt: "GCR\t\t: 0x%08x\n",
78 readl(addr: gdd + SSI_GDD_GCR_REG));
79
80 for (lch = 0; lch < SSI_MAX_GDD_LCH; lch++) {
81 seq_printf(m, fmt: "\nGDD LCH %d\n=========\n", lch);
82 seq_printf(m, fmt: "CSDP\t\t: 0x%04x\n",
83 readw(addr: gdd + SSI_GDD_CSDP_REG(lch)));
84 seq_printf(m, fmt: "CCR\t\t: 0x%04x\n",
85 readw(addr: gdd + SSI_GDD_CCR_REG(lch)));
86 seq_printf(m, fmt: "CICR\t\t: 0x%04x\n",
87 readw(addr: gdd + SSI_GDD_CICR_REG(lch)));
88 seq_printf(m, fmt: "CSR\t\t: 0x%04x\n",
89 readw(addr: gdd + SSI_GDD_CSR_REG(lch)));
90 seq_printf(m, fmt: "CSSA\t\t: 0x%08x\n",
91 readl(addr: gdd + SSI_GDD_CSSA_REG(lch)));
92 seq_printf(m, fmt: "CDSA\t\t: 0x%08x\n",
93 readl(addr: gdd + SSI_GDD_CDSA_REG(lch)));
94 seq_printf(m, fmt: "CEN\t\t: 0x%04x\n",
95 readw(addr: gdd + SSI_GDD_CEN_REG(lch)));
96 seq_printf(m, fmt: "CSAC\t\t: 0x%04x\n",
97 readw(addr: gdd + SSI_GDD_CSAC_REG(lch)));
98 seq_printf(m, fmt: "CDAC\t\t: 0x%04x\n",
99 readw(addr: gdd + SSI_GDD_CDAC_REG(lch)));
100 seq_printf(m, fmt: "CLNK_CTRL\t: 0x%04x\n",
101 readw(addr: gdd + SSI_GDD_CLNK_CTRL_REG(lch)));
102 }
103
104 pm_runtime_put(dev: 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(hsi: ssi);
115 struct dentry *dir;
116
117 /* SSI controller */
118 omap_ssi->dir = debugfs_create_dir(name: dev_name(dev: &ssi->device), NULL);
119 if (!omap_ssi->dir)
120 return -ENOMEM;
121
122 debugfs_create_file(name: "regs", S_IRUGO, parent: omap_ssi->dir, data: ssi,
123 fops: &ssi_regs_fops);
124 /* SSI GDD (DMA) */
125 dir = debugfs_create_dir(name: "gdd", parent: omap_ssi->dir);
126 if (!dir)
127 goto rback;
128 debugfs_create_file(name: "regs", S_IRUGO, parent: dir, data: ssi, fops: &ssi_gdd_regs_fops);
129
130 return 0;
131rback:
132 debugfs_remove_recursive(dentry: 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(hsi: ssi);
140
141 debugfs_remove_recursive(dentry: 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(hsi: ssi);
155
156 omap_port->wktest = !!enable;
157 if (omap_port->wktest) {
158 pm_runtime_get_sync(dev: 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(dev: 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(hsi: 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(lock: &omap_ssi->lock);
180
181 val = readl(addr: 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(dev: 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(addr: 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(lock: &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(lock: &omap_port->lock);
204 list_del(entry: &msg->link); /* Dequeue msg */
205 spin_unlock(lock: &omap_port->lock);
206
207 list_add_tail(new: &msg->link, head: &omap_port->errqueue);
208 schedule_delayed_work(dwork: &omap_port->errqueue_work, delay: 0);
209 return;
210 }
211 spin_lock(lock: &omap_port->lock);
212 val |= readl(addr: 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(lock: &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(hsi: ssi);
224 void __iomem *sys = omap_ssi->sys;
225 unsigned int lch;
226 u32 status_reg;
227
228 pm_runtime_get(dev: ssi->device.parent);
229
230 if (!pm_runtime_active(dev: ssi->device.parent)) {
231 dev_warn(ssi->device.parent, "ssi_gdd_tasklet called without runtime PM!\n");
232 pm_runtime_put(dev: ssi->device.parent);
233 return;
234 }
235
236 status_reg = readl(addr: 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(addr: sys + SSI_GDD_MPU_IRQ_STATUS_REG);
243
244 pm_runtime_put(dev: ssi->device.parent);
245
246 if (status_reg)
247 tasklet_hi_schedule(t: &omap_ssi->gdd_tasklet);
248 else
249 enable_irq(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(hsi: ssi);
256
257 tasklet_hi_schedule(t: &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(hsi: ssi);
266 unsigned long rate = clk_get_rate(clk: 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(irq: omap_port->wake_irq);
292
293 /* stop all ssi communication */
294 pinctrl_pm_select_idle_state(dev: 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(dev: omap_port->pdev);
317 enable_irq(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(pdev: pd);
334
335 mem = platform_get_resource_byname(pd, IORESOURCE_MEM, name);
336 base = devm_ioremap_resource(dev: &ssi->device, res: mem);
337 if (IS_ERR(ptr: base))
338 return PTR_ERR(ptr: 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(dev: &ssi->device, size: sizeof(*omap_ssi), GFP_KERNEL);
355 if (!omap_ssi)
356 return -ENOMEM;
357
358 err = ida_alloc(ida: &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(dev: &ssi->device, name: "ssi%d", ssi->id);
366 hsi_controller_set_drvdata(hsi: ssi, data: omap_ssi);
367 omap_ssi->dev = &ssi->device;
368 err = ssi_get_iomem(pd, name: "sys", pbase: &omap_ssi->sys, NULL);
369 if (err < 0)
370 goto out_err;
371 err = ssi_get_iomem(pd, name: "gdd", pbase: &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(t: &omap_ssi->gdd_tasklet, func: ssi_gdd_tasklet,
379 data: (unsigned long)ssi);
380 err = devm_request_irq(dev: &ssi->device, irq: omap_ssi->gdd_irq, handler: ssi_gdd_isr,
381 irqflags: 0, devname: "gdd_mpu", dev_id: 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(dev: &ssi->device, n: ssi->num_ports,
389 size: 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(dev: &ssi->device, id: "ssi_ssr_fck");
396 if (IS_ERR(ptr: 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(clk: omap_ssi->fck, nb: &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(hsi: ssi);
413
414 if (err < 0)
415 goto out_err;
416
417 return 0;
418
419out_err:
420 ida_free(&platform_omap_ssi_ida, id: 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(hsi: ssi);
427 int err;
428
429 err = pm_runtime_resume_and_get(dev: 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(dev: 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(hsi: ssi);
450 int id = ssi->id;
451 tasklet_kill(t: &omap_ssi->gdd_tasklet);
452 hsi_unregister_controller(hsi: ssi);
453 clk_notifier_unregister(clk: omap_ssi->fck, nb: &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(device: 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(n: dev->of_node, OF_POPULATED);
477 of_device_unregister(ofdev: 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(n_ports: 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(pdev: pd, data: ssi);
505
506 err = ssi_add_controller(ssi, pd);
507 if (err < 0) {
508 hsi_put_controller(hsi: ssi);
509 goto out1;
510 }
511
512 pm_runtime_enable(dev: &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(device: child, "ti,omap3-ssi-port"))
525 continue;
526
527 childpdev = of_platform_device_create(np: child, NULL, parent: &pd->dev);
528 if (!childpdev) {
529 err = -ENODEV;
530 dev_err(&pd->dev, "failed to create ssi controller port\n");
531 of_node_put(node: 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(dev: &pd->dev, NULL, fn: ssi_remove_ports);
541out2:
542 ssi_remove_controller(ssi);
543 pm_runtime_disable(dev: &pd->dev);
544out1:
545 platform_set_drvdata(pdev: 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(pdev: pd);
553
554 /* cleanup of of_platform_populate() call */
555 device_for_each_child(dev: &pd->dev, NULL, fn: 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(pdev: pd, NULL);
562
563 pm_runtime_disable(dev: &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(hsi: 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(hsi: 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

source code of linux/drivers/hsi/controllers/omap_ssi_core.c