1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
4  * Authors: Ludovic Barre <ludovic.barre@st.com> for STMicroelectronics.
5  *          Fabien Dessenne <fabien.dessenne@st.com> for STMicroelectronics.
6  */
7 
8 #include <linux/arm-smccc.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/mailbox_client.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/of_reserved_mem.h>
18 #include <linux/pm_wakeirq.h>
19 #include <linux/regmap.h>
20 #include <linux/remoteproc.h>
21 #include <linux/reset.h>
22 #include <linux/slab.h>
23 #include <linux/workqueue.h>
24 
25 #include "remoteproc_internal.h"
26 
27 #define HOLD_BOOT		0
28 #define RELEASE_BOOT		1
29 
30 #define MBOX_NB_VQ		2
31 #define MBOX_NB_MBX		3
32 
33 #define STM32_SMC_RCC		0x82001000
34 #define STM32_SMC_REG_WRITE	0x1
35 
36 #define STM32_MBX_VQ0		"vq0"
37 #define STM32_MBX_VQ0_ID	0
38 #define STM32_MBX_VQ1		"vq1"
39 #define STM32_MBX_VQ1_ID	1
40 #define STM32_MBX_SHUTDOWN	"shutdown"
41 
42 struct stm32_syscon {
43 	struct regmap *map;
44 	u32 reg;
45 	u32 mask;
46 };
47 
48 struct stm32_rproc_mem {
49 	char name[20];
50 	void __iomem *cpu_addr;
51 	phys_addr_t bus_addr;
52 	u32 dev_addr;
53 	size_t size;
54 };
55 
56 struct stm32_rproc_mem_ranges {
57 	u32 dev_addr;
58 	u32 bus_addr;
59 	u32 size;
60 };
61 
62 struct stm32_mbox {
63 	const unsigned char name[10];
64 	struct mbox_chan *chan;
65 	struct mbox_client client;
66 	struct work_struct vq_work;
67 	int vq_id;
68 };
69 
70 struct stm32_rproc {
71 	struct reset_control *rst;
72 	struct stm32_syscon hold_boot;
73 	struct stm32_syscon pdds;
74 	int wdg_irq;
75 	u32 nb_rmems;
76 	struct stm32_rproc_mem *rmems;
77 	struct stm32_mbox mb[MBOX_NB_MBX];
78 	struct workqueue_struct *workqueue;
79 	bool secured_soc;
80 };
81 
82 static int stm32_rproc_pa_to_da(struct rproc *rproc, phys_addr_t pa, u64 *da)
83 {
84 	unsigned int i;
85 	struct stm32_rproc *ddata = rproc->priv;
86 	struct stm32_rproc_mem *p_mem;
87 
88 	for (i = 0; i < ddata->nb_rmems; i++) {
89 		p_mem = &ddata->rmems[i];
90 
91 		if (pa < p_mem->bus_addr ||
92 		    pa >= p_mem->bus_addr + p_mem->size)
93 			continue;
94 		*da = pa - p_mem->bus_addr + p_mem->dev_addr;
95 		dev_dbg(rproc->dev.parent, "pa %pa to da %llx\n", &pa, *da);
96 		return 0;
97 	}
98 
99 	return -EINVAL;
100 }
101 
102 static int stm32_rproc_mem_alloc(struct rproc *rproc,
103 				 struct rproc_mem_entry *mem)
104 {
105 	struct device *dev = rproc->dev.parent;
106 	void *va;
107 
108 	dev_dbg(dev, "map memory: %pa+%x\n", &mem->dma, mem->len);
109 	va = ioremap_wc(mem->dma, mem->len);
110 	if (IS_ERR_OR_NULL(va)) {
111 		dev_err(dev, "Unable to map memory region: %pa+%x\n",
112 			&mem->dma, mem->len);
113 		return -ENOMEM;
114 	}
115 
116 	/* Update memory entry va */
117 	mem->va = va;
118 
119 	return 0;
120 }
121 
122 static int stm32_rproc_mem_release(struct rproc *rproc,
123 				   struct rproc_mem_entry *mem)
124 {
125 	dev_dbg(rproc->dev.parent, "unmap memory: %pa\n", &mem->dma);
126 	iounmap(mem->va);
127 
128 	return 0;
129 }
130 
131 static int stm32_rproc_of_memory_translations(struct rproc *rproc)
132 {
133 	struct device *parent, *dev = rproc->dev.parent;
134 	struct stm32_rproc *ddata = rproc->priv;
135 	struct device_node *np;
136 	struct stm32_rproc_mem *p_mems;
137 	struct stm32_rproc_mem_ranges *mem_range;
138 	int cnt, array_size, i, ret = 0;
139 
140 	parent = dev->parent;
141 	np = parent->of_node;
142 
143 	cnt = of_property_count_elems_of_size(np, "dma-ranges",
144 					      sizeof(*mem_range));
145 	if (cnt <= 0) {
146 		dev_err(dev, "%s: dma-ranges property not defined\n", __func__);
147 		return -EINVAL;
148 	}
149 
150 	p_mems = devm_kcalloc(dev, cnt, sizeof(*p_mems), GFP_KERNEL);
151 	if (!p_mems)
152 		return -ENOMEM;
153 	mem_range = kcalloc(cnt, sizeof(*mem_range), GFP_KERNEL);
154 	if (!mem_range)
155 		return -ENOMEM;
156 
157 	array_size = cnt * sizeof(struct stm32_rproc_mem_ranges) / sizeof(u32);
158 
159 	ret = of_property_read_u32_array(np, "dma-ranges",
160 					 (u32 *)mem_range, array_size);
161 	if (ret) {
162 		dev_err(dev, "error while get dma-ranges property: %x\n", ret);
163 		goto free_mem;
164 	}
165 
166 	for (i = 0; i < cnt; i++) {
167 		p_mems[i].bus_addr = mem_range[i].bus_addr;
168 		p_mems[i].dev_addr = mem_range[i].dev_addr;
169 		p_mems[i].size     = mem_range[i].size;
170 
171 		dev_dbg(dev, "memory range[%i]: da %#x, pa %pa, size %#zx:\n",
172 			i, p_mems[i].dev_addr, &p_mems[i].bus_addr,
173 			p_mems[i].size);
174 	}
175 
176 	ddata->rmems = p_mems;
177 	ddata->nb_rmems = cnt;
178 
179 free_mem:
180 	kfree(mem_range);
181 	return ret;
182 }
183 
184 static int stm32_rproc_mbox_idx(struct rproc *rproc, const unsigned char *name)
185 {
186 	struct stm32_rproc *ddata = rproc->priv;
187 	int i;
188 
189 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
190 		if (!strncmp(ddata->mb[i].name, name, strlen(name)))
191 			return i;
192 	}
193 	dev_err(&rproc->dev, "mailbox %s not found\n", name);
194 
195 	return -EINVAL;
196 }
197 
198 static int stm32_rproc_elf_load_rsc_table(struct rproc *rproc,
199 					  const struct firmware *fw)
200 {
201 	if (rproc_elf_load_rsc_table(rproc, fw))
202 		dev_warn(&rproc->dev, "no resource table found for this firmware\n");
203 
204 	return 0;
205 }
206 
207 static int stm32_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
208 {
209 	struct device *dev = rproc->dev.parent;
210 	struct device_node *np = dev->of_node;
211 	struct of_phandle_iterator it;
212 	struct rproc_mem_entry *mem;
213 	struct reserved_mem *rmem;
214 	u64 da;
215 	int index = 0;
216 
217 	/* Register associated reserved memory regions */
218 	of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
219 	while (of_phandle_iterator_next(&it) == 0) {
220 		rmem = of_reserved_mem_lookup(it.node);
221 		if (!rmem) {
222 			dev_err(dev, "unable to acquire memory-region\n");
223 			return -EINVAL;
224 		}
225 
226 		if (stm32_rproc_pa_to_da(rproc, rmem->base, &da) < 0) {
227 			dev_err(dev, "memory region not valid %pa\n",
228 				&rmem->base);
229 			return -EINVAL;
230 		}
231 
232 		/*  No need to map vdev buffer */
233 		if (strcmp(it.node->name, "vdev0buffer")) {
234 			/* Register memory region */
235 			mem = rproc_mem_entry_init(dev, NULL,
236 						   (dma_addr_t)rmem->base,
237 						   rmem->size, da,
238 						   stm32_rproc_mem_alloc,
239 						   stm32_rproc_mem_release,
240 						   it.node->name);
241 
242 			if (mem)
243 				rproc_coredump_add_segment(rproc, da,
244 							   rmem->size);
245 		} else {
246 			/* Register reserved memory for vdev buffer alloc */
247 			mem = rproc_of_resm_mem_entry_init(dev, index,
248 							   rmem->size,
249 							   rmem->base,
250 							   it.node->name);
251 		}
252 
253 		if (!mem)
254 			return -ENOMEM;
255 
256 		rproc_add_carveout(rproc, mem);
257 		index++;
258 	}
259 
260 	return stm32_rproc_elf_load_rsc_table(rproc, fw);
261 }
262 
263 static irqreturn_t stm32_rproc_wdg(int irq, void *data)
264 {
265 	struct rproc *rproc = data;
266 
267 	rproc_report_crash(rproc, RPROC_WATCHDOG);
268 
269 	return IRQ_HANDLED;
270 }
271 
272 static void stm32_rproc_mb_vq_work(struct work_struct *work)
273 {
274 	struct stm32_mbox *mb = container_of(work, struct stm32_mbox, vq_work);
275 	struct rproc *rproc = dev_get_drvdata(mb->client.dev);
276 
277 	if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)
278 		dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);
279 }
280 
281 static void stm32_rproc_mb_callback(struct mbox_client *cl, void *data)
282 {
283 	struct rproc *rproc = dev_get_drvdata(cl->dev);
284 	struct stm32_mbox *mb = container_of(cl, struct stm32_mbox, client);
285 	struct stm32_rproc *ddata = rproc->priv;
286 
287 	queue_work(ddata->workqueue, &mb->vq_work);
288 }
289 
290 static void stm32_rproc_free_mbox(struct rproc *rproc)
291 {
292 	struct stm32_rproc *ddata = rproc->priv;
293 	unsigned int i;
294 
295 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
296 		if (ddata->mb[i].chan)
297 			mbox_free_channel(ddata->mb[i].chan);
298 		ddata->mb[i].chan = NULL;
299 	}
300 }
301 
302 static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
303 	{
304 		.name = STM32_MBX_VQ0,
305 		.vq_id = STM32_MBX_VQ0_ID,
306 		.client = {
307 			.rx_callback = stm32_rproc_mb_callback,
308 			.tx_block = false,
309 		},
310 	},
311 	{
312 		.name = STM32_MBX_VQ1,
313 		.vq_id = STM32_MBX_VQ1_ID,
314 		.client = {
315 			.rx_callback = stm32_rproc_mb_callback,
316 			.tx_block = false,
317 		},
318 	},
319 	{
320 		.name = STM32_MBX_SHUTDOWN,
321 		.vq_id = -1,
322 		.client = {
323 			.tx_block = true,
324 			.tx_done = NULL,
325 			.tx_tout = 500, /* 500 ms time out */
326 		},
327 	}
328 };
329 
330 static int stm32_rproc_request_mbox(struct rproc *rproc)
331 {
332 	struct stm32_rproc *ddata = rproc->priv;
333 	struct device *dev = &rproc->dev;
334 	unsigned int i;
335 	int j;
336 	const unsigned char *name;
337 	struct mbox_client *cl;
338 
339 	/* Initialise mailbox structure table */
340 	memcpy(ddata->mb, stm32_rproc_mbox, sizeof(stm32_rproc_mbox));
341 
342 	for (i = 0; i < MBOX_NB_MBX; i++) {
343 		name = ddata->mb[i].name;
344 
345 		cl = &ddata->mb[i].client;
346 		cl->dev = dev->parent;
347 
348 		ddata->mb[i].chan = mbox_request_channel_byname(cl, name);
349 		if (IS_ERR(ddata->mb[i].chan)) {
350 			if (PTR_ERR(ddata->mb[i].chan) == -EPROBE_DEFER)
351 				goto err_probe;
352 			dev_warn(dev, "cannot get %s mbox\n", name);
353 			ddata->mb[i].chan = NULL;
354 		}
355 		if (ddata->mb[i].vq_id >= 0) {
356 			INIT_WORK(&ddata->mb[i].vq_work,
357 				  stm32_rproc_mb_vq_work);
358 		}
359 	}
360 
361 	return 0;
362 
363 err_probe:
364 	for (j = i - 1; j >= 0; j--)
365 		if (ddata->mb[j].chan)
366 			mbox_free_channel(ddata->mb[j].chan);
367 	return -EPROBE_DEFER;
368 }
369 
370 static int stm32_rproc_set_hold_boot(struct rproc *rproc, bool hold)
371 {
372 	struct stm32_rproc *ddata = rproc->priv;
373 	struct stm32_syscon hold_boot = ddata->hold_boot;
374 	struct arm_smccc_res smc_res;
375 	int val, err;
376 
377 	val = hold ? HOLD_BOOT : RELEASE_BOOT;
378 
379 	if (IS_ENABLED(CONFIG_HAVE_ARM_SMCCC) && ddata->secured_soc) {
380 		arm_smccc_smc(STM32_SMC_RCC, STM32_SMC_REG_WRITE,
381 			      hold_boot.reg, val, 0, 0, 0, 0, &smc_res);
382 		err = smc_res.a0;
383 	} else {
384 		err = regmap_update_bits(hold_boot.map, hold_boot.reg,
385 					 hold_boot.mask, val);
386 	}
387 
388 	if (err)
389 		dev_err(&rproc->dev, "failed to set hold boot\n");
390 
391 	return err;
392 }
393 
394 static void stm32_rproc_add_coredump_trace(struct rproc *rproc)
395 {
396 	struct rproc_debug_trace *trace;
397 	struct rproc_dump_segment *segment;
398 	bool already_added;
399 
400 	list_for_each_entry(trace, &rproc->traces, node) {
401 		already_added = false;
402 
403 		list_for_each_entry(segment, &rproc->dump_segments, node) {
404 			if (segment->da == trace->trace_mem.da) {
405 				already_added = true;
406 				break;
407 			}
408 		}
409 
410 		if (!already_added)
411 			rproc_coredump_add_segment(rproc, trace->trace_mem.da,
412 						   trace->trace_mem.len);
413 	}
414 }
415 
416 static int stm32_rproc_start(struct rproc *rproc)
417 {
418 	struct stm32_rproc *ddata = rproc->priv;
419 	int err;
420 
421 	stm32_rproc_add_coredump_trace(rproc);
422 
423 	/* clear remote proc Deep Sleep */
424 	if (ddata->pdds.map) {
425 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
426 					 ddata->pdds.mask, 0);
427 		if (err) {
428 			dev_err(&rproc->dev, "failed to clear pdds\n");
429 			return err;
430 		}
431 	}
432 
433 	err = stm32_rproc_set_hold_boot(rproc, false);
434 	if (err)
435 		return err;
436 
437 	return stm32_rproc_set_hold_boot(rproc, true);
438 }
439 
440 static int stm32_rproc_stop(struct rproc *rproc)
441 {
442 	struct stm32_rproc *ddata = rproc->priv;
443 	int err, dummy_data, idx;
444 
445 	/* request shutdown of the remote processor */
446 	if (rproc->state != RPROC_OFFLINE) {
447 		idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN);
448 		if (idx >= 0 && ddata->mb[idx].chan) {
449 			/* a dummy data is sent to allow to block on transmit */
450 			err = mbox_send_message(ddata->mb[idx].chan,
451 						&dummy_data);
452 			if (err < 0)
453 				dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n");
454 		}
455 	}
456 
457 	err = stm32_rproc_set_hold_boot(rproc, true);
458 	if (err)
459 		return err;
460 
461 	err = reset_control_assert(ddata->rst);
462 	if (err) {
463 		dev_err(&rproc->dev, "failed to assert the reset\n");
464 		return err;
465 	}
466 
467 	/* to allow platform Standby power mode, set remote proc Deep Sleep */
468 	if (ddata->pdds.map) {
469 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
470 					 ddata->pdds.mask, 1);
471 		if (err) {
472 			dev_err(&rproc->dev, "failed to set pdds\n");
473 			return err;
474 		}
475 	}
476 
477 	return 0;
478 }
479 
480 static void stm32_rproc_kick(struct rproc *rproc, int vqid)
481 {
482 	struct stm32_rproc *ddata = rproc->priv;
483 	unsigned int i;
484 	int err;
485 
486 	if (WARN_ON(vqid >= MBOX_NB_VQ))
487 		return;
488 
489 	for (i = 0; i < MBOX_NB_MBX; i++) {
490 		if (vqid != ddata->mb[i].vq_id)
491 			continue;
492 		if (!ddata->mb[i].chan)
493 			return;
494 		err = mbox_send_message(ddata->mb[i].chan, (void *)(long)vqid);
495 		if (err < 0)
496 			dev_err(&rproc->dev, "%s: failed (%s, err:%d)\n",
497 				__func__, ddata->mb[i].name, err);
498 		return;
499 	}
500 }
501 
502 static struct rproc_ops st_rproc_ops = {
503 	.start		= stm32_rproc_start,
504 	.stop		= stm32_rproc_stop,
505 	.kick		= stm32_rproc_kick,
506 	.load		= rproc_elf_load_segments,
507 	.parse_fw	= stm32_rproc_parse_fw,
508 	.find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table,
509 	.sanity_check	= rproc_elf32_sanity_check,
510 	.get_boot_addr	= rproc_elf_get_boot_addr,
511 };
512 
513 static const struct of_device_id stm32_rproc_match[] = {
514 	{ .compatible = "st,stm32mp1-m4" },
515 	{},
516 };
517 MODULE_DEVICE_TABLE(of, stm32_rproc_match);
518 
519 static int stm32_rproc_get_syscon(struct device_node *np, const char *prop,
520 				  struct stm32_syscon *syscon)
521 {
522 	int err = 0;
523 
524 	syscon->map = syscon_regmap_lookup_by_phandle(np, prop);
525 	if (IS_ERR(syscon->map)) {
526 		err = PTR_ERR(syscon->map);
527 		syscon->map = NULL;
528 		goto out;
529 	}
530 
531 	err = of_property_read_u32_index(np, prop, 1, &syscon->reg);
532 	if (err)
533 		goto out;
534 
535 	err = of_property_read_u32_index(np, prop, 2, &syscon->mask);
536 
537 out:
538 	return err;
539 }
540 
541 static int stm32_rproc_parse_dt(struct platform_device *pdev)
542 {
543 	struct device *dev = &pdev->dev;
544 	struct device_node *np = dev->of_node;
545 	struct rproc *rproc = platform_get_drvdata(pdev);
546 	struct stm32_rproc *ddata = rproc->priv;
547 	struct stm32_syscon tz;
548 	unsigned int tzen;
549 	int err, irq;
550 
551 	irq = platform_get_irq(pdev, 0);
552 	if (irq == -EPROBE_DEFER)
553 		return -EPROBE_DEFER;
554 
555 	if (irq > 0) {
556 		err = devm_request_irq(dev, irq, stm32_rproc_wdg, 0,
557 				       dev_name(dev), rproc);
558 		if (err) {
559 			dev_err(dev, "failed to request wdg irq\n");
560 			return err;
561 		}
562 
563 		ddata->wdg_irq = irq;
564 
565 		if (of_property_read_bool(np, "wakeup-source")) {
566 			device_init_wakeup(dev, true);
567 			dev_pm_set_wake_irq(dev, irq);
568 		}
569 
570 		dev_info(dev, "wdg irq registered\n");
571 	}
572 
573 	ddata->rst = devm_reset_control_get_by_index(dev, 0);
574 	if (IS_ERR(ddata->rst)) {
575 		dev_err(dev, "failed to get mcu reset\n");
576 		return PTR_ERR(ddata->rst);
577 	}
578 
579 	/*
580 	 * if platform is secured the hold boot bit must be written by
581 	 * smc call and read normally.
582 	 * if not secure the hold boot bit could be read/write normally
583 	 */
584 	err = stm32_rproc_get_syscon(np, "st,syscfg-tz", &tz);
585 	if (err) {
586 		dev_err(dev, "failed to get tz syscfg\n");
587 		return err;
588 	}
589 
590 	err = regmap_read(tz.map, tz.reg, &tzen);
591 	if (err) {
592 		dev_err(&rproc->dev, "failed to read tzen\n");
593 		return err;
594 	}
595 	ddata->secured_soc = tzen & tz.mask;
596 
597 	err = stm32_rproc_get_syscon(np, "st,syscfg-holdboot",
598 				     &ddata->hold_boot);
599 	if (err) {
600 		dev_err(dev, "failed to get hold boot\n");
601 		return err;
602 	}
603 
604 	err = stm32_rproc_get_syscon(np, "st,syscfg-pdds", &ddata->pdds);
605 	if (err)
606 		dev_info(dev, "failed to get pdds\n");
607 
608 	rproc->auto_boot = of_property_read_bool(np, "st,auto-boot");
609 
610 	return stm32_rproc_of_memory_translations(rproc);
611 }
612 
613 static int stm32_rproc_probe(struct platform_device *pdev)
614 {
615 	struct device *dev = &pdev->dev;
616 	struct stm32_rproc *ddata;
617 	struct device_node *np = dev->of_node;
618 	struct rproc *rproc;
619 	int ret;
620 
621 	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
622 	if (ret)
623 		return ret;
624 
625 	rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
626 	if (!rproc)
627 		return -ENOMEM;
628 
629 	rproc->has_iommu = false;
630 	ddata = rproc->priv;
631 	ddata->workqueue = create_workqueue(dev_name(dev));
632 	if (!ddata->workqueue) {
633 		dev_err(dev, "cannot create workqueue\n");
634 		ret = -ENOMEM;
635 		goto free_rproc;
636 	}
637 
638 	platform_set_drvdata(pdev, rproc);
639 
640 	ret = stm32_rproc_parse_dt(pdev);
641 	if (ret)
642 		goto free_wkq;
643 
644 	ret = stm32_rproc_request_mbox(rproc);
645 	if (ret)
646 		goto free_rproc;
647 
648 	ret = rproc_add(rproc);
649 	if (ret)
650 		goto free_mb;
651 
652 	return 0;
653 
654 free_mb:
655 	stm32_rproc_free_mbox(rproc);
656 free_wkq:
657 	destroy_workqueue(ddata->workqueue);
658 free_rproc:
659 	if (device_may_wakeup(dev)) {
660 		dev_pm_clear_wake_irq(dev);
661 		device_init_wakeup(dev, false);
662 	}
663 	rproc_free(rproc);
664 	return ret;
665 }
666 
667 static int stm32_rproc_remove(struct platform_device *pdev)
668 {
669 	struct rproc *rproc = platform_get_drvdata(pdev);
670 	struct stm32_rproc *ddata = rproc->priv;
671 	struct device *dev = &pdev->dev;
672 
673 	if (atomic_read(&rproc->power) > 0)
674 		rproc_shutdown(rproc);
675 
676 	rproc_del(rproc);
677 	stm32_rproc_free_mbox(rproc);
678 	destroy_workqueue(ddata->workqueue);
679 
680 	if (device_may_wakeup(dev)) {
681 		dev_pm_clear_wake_irq(dev);
682 		device_init_wakeup(dev, false);
683 	}
684 	rproc_free(rproc);
685 
686 	return 0;
687 }
688 
689 static int __maybe_unused stm32_rproc_suspend(struct device *dev)
690 {
691 	struct rproc *rproc = dev_get_drvdata(dev);
692 	struct stm32_rproc *ddata = rproc->priv;
693 
694 	if (device_may_wakeup(dev))
695 		return enable_irq_wake(ddata->wdg_irq);
696 
697 	return 0;
698 }
699 
700 static int __maybe_unused stm32_rproc_resume(struct device *dev)
701 {
702 	struct rproc *rproc = dev_get_drvdata(dev);
703 	struct stm32_rproc *ddata = rproc->priv;
704 
705 	if (device_may_wakeup(dev))
706 		return disable_irq_wake(ddata->wdg_irq);
707 
708 	return 0;
709 }
710 
711 static SIMPLE_DEV_PM_OPS(stm32_rproc_pm_ops,
712 			 stm32_rproc_suspend, stm32_rproc_resume);
713 
714 static struct platform_driver stm32_rproc_driver = {
715 	.probe = stm32_rproc_probe,
716 	.remove = stm32_rproc_remove,
717 	.driver = {
718 		.name = "stm32-rproc",
719 		.pm = &stm32_rproc_pm_ops,
720 		.of_match_table = of_match_ptr(stm32_rproc_match),
721 	},
722 };
723 module_platform_driver(stm32_rproc_driver);
724 
725 MODULE_DESCRIPTION("STM32 Remote Processor Control Driver");
726 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
727 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
728 MODULE_LICENSE("GPL v2");
729 
730