xref: /linux/drivers/soundwire/intel_auxdevice.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 // Copyright(c) 2015-22 Intel Corporation.
3 
4 /*
5  * Soundwire Intel Manager Driver
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/debugfs.h>
10 #include <linux/delay.h>
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/auxiliary_bus.h>
15 #include <sound/pcm_params.h>
16 #include <linux/pm_runtime.h>
17 #include <sound/soc.h>
18 #include <linux/soundwire/sdw_registers.h>
19 #include <linux/soundwire/sdw.h>
20 #include <linux/soundwire/sdw_intel.h>
21 #include "cadence_master.h"
22 #include "bus.h"
23 #include "intel.h"
24 #include "intel_auxdevice.h"
25 
26 #define INTEL_MASTER_SUSPEND_DELAY_MS	3000
27 
28 /*
29  * debug/config flags for the Intel SoundWire Master.
30  *
31  * Since we may have multiple masters active, we can have up to 8
32  * flags reused in each byte, with master0 using the ls-byte, etc.
33  */
34 
35 #define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME		BIT(0)
36 #define SDW_INTEL_MASTER_DISABLE_CLOCK_STOP		BIT(1)
37 #define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE	BIT(2)
38 #define SDW_INTEL_MASTER_DISABLE_MULTI_LINK		BIT(3)
39 
40 static int md_flags;
41 module_param_named(sdw_md_flags, md_flags, int, 0444);
42 MODULE_PARM_DESC(sdw_md_flags, "SoundWire Intel Master device flags (0x0 all off)");
43 
44 static int mclk_divider;
45 module_param_named(sdw_mclk_divider, mclk_divider, int, 0444);
46 MODULE_PARM_DESC(sdw_mclk_divider, "SoundWire Intel mclk divider");
47 
48 struct wake_capable_part {
49 	const u16 mfg_id;
50 	const u16 part_id;
51 };
52 
53 static struct wake_capable_part wake_capable_list[] = {
54 	{0x01fa, 0x4243},
55 	{0x025d, 0x5682},
56 	{0x025d, 0x700},
57 	{0x025d, 0x711},
58 	{0x025d, 0x1712},
59 	{0x025d, 0x1713},
60 	{0x025d, 0x1716},
61 	{0x025d, 0x1717},
62 	{0x025d, 0x712},
63 	{0x025d, 0x713},
64 	{0x025d, 0x714},
65 	{0x025d, 0x715},
66 	{0x025d, 0x716},
67 	{0x025d, 0x717},
68 	{0x025d, 0x722},
69 };
70 
71 static bool is_wake_capable(struct sdw_slave *slave)
72 {
73 	int i;
74 
75 	for (i = 0; i < ARRAY_SIZE(wake_capable_list); i++)
76 		if (slave->id.part_id == wake_capable_list[i].part_id &&
77 		    slave->id.mfg_id == wake_capable_list[i].mfg_id)
78 			return true;
79 	return false;
80 }
81 
82 static int generic_pre_bank_switch(struct sdw_bus *bus)
83 {
84 	struct sdw_cdns *cdns = bus_to_cdns(bus);
85 	struct sdw_intel *sdw = cdns_to_intel(cdns);
86 
87 	return sdw->link_res->hw_ops->pre_bank_switch(sdw);
88 }
89 
90 static int generic_post_bank_switch(struct sdw_bus *bus)
91 {
92 	struct sdw_cdns *cdns = bus_to_cdns(bus);
93 	struct sdw_intel *sdw = cdns_to_intel(cdns);
94 
95 	return sdw->link_res->hw_ops->post_bank_switch(sdw);
96 }
97 
98 static void generic_new_peripheral_assigned(struct sdw_bus *bus,
99 					    struct sdw_slave *slave,
100 					    int dev_num)
101 {
102 	struct sdw_cdns *cdns = bus_to_cdns(bus);
103 	struct sdw_intel *sdw = cdns_to_intel(cdns);
104 	int dev_num_min;
105 	int dev_num_max;
106 	bool wake_capable = slave->prop.wake_capable || is_wake_capable(slave);
107 
108 	if (wake_capable) {
109 		dev_num_min = SDW_INTEL_DEV_NUM_IDA_MIN;
110 		dev_num_max = SDW_MAX_DEVICES;
111 	} else {
112 		dev_num_min = 1;
113 		dev_num_max = SDW_INTEL_DEV_NUM_IDA_MIN - 1;
114 	}
115 
116 	/* paranoia check, this should never happen */
117 	if (dev_num < dev_num_min || dev_num > dev_num_max)  {
118 		dev_err(bus->dev, "%s: invalid dev_num %d, wake supported %d\n",
119 			__func__, dev_num, slave->prop.wake_capable);
120 		return;
121 	}
122 
123 	if (sdw->link_res->hw_ops->program_sdi && wake_capable)
124 		sdw->link_res->hw_ops->program_sdi(sdw, dev_num);
125 }
126 
127 static int sdw_master_read_intel_prop(struct sdw_bus *bus)
128 {
129 	struct sdw_master_prop *prop = &bus->prop;
130 	struct sdw_intel_prop *intel_prop;
131 	struct fwnode_handle *link;
132 	char name[32];
133 	u32 quirk_mask;
134 
135 	/* Find master handle */
136 	snprintf(name, sizeof(name),
137 		 "mipi-sdw-link-%d-subproperties", bus->link_id);
138 
139 	link = device_get_named_child_node(bus->dev, name);
140 	if (!link) {
141 		dev_err(bus->dev, "Master node %s not found\n", name);
142 		return -EIO;
143 	}
144 
145 	fwnode_property_read_u32(link,
146 				 "intel-sdw-ip-clock",
147 				 &prop->mclk_freq);
148 
149 	if (mclk_divider)
150 		/* use kernel parameter for BIOS or board work-arounds */
151 		prop->mclk_freq /= mclk_divider;
152 	else
153 		/* the values reported by BIOS are the 2x clock, not the bus clock */
154 		prop->mclk_freq /= 2;
155 
156 	fwnode_property_read_u32(link,
157 				 "intel-quirk-mask",
158 				 &quirk_mask);
159 
160 	if (quirk_mask & SDW_INTEL_QUIRK_MASK_BUS_DISABLE)
161 		prop->hw_disabled = true;
162 
163 	prop->quirks = SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH |
164 		SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY;
165 
166 	intel_prop = devm_kzalloc(bus->dev, sizeof(*intel_prop), GFP_KERNEL);
167 	if (!intel_prop) {
168 		fwnode_handle_put(link);
169 		return -ENOMEM;
170 	}
171 
172 	/* initialize with hardware defaults, in case the properties are not found */
173 	intel_prop->clde = 0x0;
174 	intel_prop->doaise2 = 0x0;
175 	intel_prop->dodse2 = 0x0;
176 	intel_prop->clds = 0x0;
177 	intel_prop->clss = 0x0;
178 	intel_prop->doaise = 0x1;
179 	intel_prop->doais = 0x3;
180 	intel_prop->dodse  = 0x0;
181 	intel_prop->dods  = 0x1;
182 
183 	fwnode_property_read_u16(link,
184 				 "intel-sdw-clde",
185 				 &intel_prop->clde);
186 	fwnode_property_read_u16(link,
187 				 "intel-sdw-doaise2",
188 				 &intel_prop->doaise2);
189 	fwnode_property_read_u16(link,
190 				 "intel-sdw-dodse2",
191 				 &intel_prop->dodse2);
192 	fwnode_property_read_u16(link,
193 				 "intel-sdw-clds",
194 				 &intel_prop->clds);
195 	fwnode_property_read_u16(link,
196 				 "intel-sdw-clss",
197 				 &intel_prop->clss);
198 	fwnode_property_read_u16(link,
199 				 "intel-sdw-doaise",
200 				 &intel_prop->doaise);
201 	fwnode_property_read_u16(link,
202 				 "intel-sdw-doais",
203 				 &intel_prop->doais);
204 	fwnode_property_read_u16(link,
205 				 "intel-sdw-dodse",
206 				 &intel_prop->dodse);
207 	fwnode_property_read_u16(link,
208 				 "intel-sdw-dods",
209 				 &intel_prop->dods);
210 	bus->vendor_specific_prop = intel_prop;
211 
212 	dev_dbg(bus->dev, "doaise %#x doais %#x dodse %#x dods %#x\n",
213 		intel_prop->doaise,
214 		intel_prop->doais,
215 		intel_prop->dodse,
216 		intel_prop->dods);
217 
218 	fwnode_handle_put(link);
219 
220 	return 0;
221 }
222 
223 static int intel_prop_read(struct sdw_bus *bus)
224 {
225 	struct sdw_master_prop *prop;
226 
227 	/* Initialize with default handler to read all DisCo properties */
228 	sdw_master_read_prop(bus);
229 
230 	/*
231 	 * Only one bus frequency is supported so far, filter
232 	 * frequencies reported in the DSDT
233 	 */
234 	prop = &bus->prop;
235 	if (prop->clk_freq && prop->num_clk_freq > 1) {
236 		unsigned int default_bus_frequency;
237 
238 		default_bus_frequency =
239 			prop->default_frame_rate *
240 			prop->default_row *
241 			prop->default_col /
242 			SDW_DOUBLE_RATE_FACTOR;
243 
244 		prop->num_clk_freq = 1;
245 		prop->clk_freq[0] = default_bus_frequency;
246 		prop->max_clk_freq = default_bus_frequency;
247 	}
248 
249 	/* read Intel-specific properties */
250 	sdw_master_read_intel_prop(bus);
251 
252 	return 0;
253 }
254 
255 static DEFINE_IDA(intel_peripheral_ida);
256 
257 static int intel_get_device_num_ida(struct sdw_bus *bus, struct sdw_slave *slave)
258 {
259 	int bit;
260 
261 	if (slave->prop.wake_capable || is_wake_capable(slave))
262 		return ida_alloc_range(&intel_peripheral_ida,
263 				       SDW_INTEL_DEV_NUM_IDA_MIN, SDW_MAX_DEVICES,
264 				       GFP_KERNEL);
265 
266 	bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
267 	if (bit == SDW_MAX_DEVICES)
268 		return -ENODEV;
269 
270 	return bit;
271 }
272 
273 static void intel_put_device_num_ida(struct sdw_bus *bus, struct sdw_slave *slave)
274 {
275 	if (slave->prop.wake_capable || is_wake_capable(slave))
276 		ida_free(&intel_peripheral_ida, slave->dev_num);
277 }
278 
279 static struct sdw_master_ops sdw_intel_ops = {
280 	.read_prop = intel_prop_read,
281 	.override_adr = sdw_dmi_override_adr,
282 	.xfer_msg = cdns_xfer_msg,
283 	.xfer_msg_defer = cdns_xfer_msg_defer,
284 	.set_bus_conf = cdns_bus_conf,
285 	.pre_bank_switch = generic_pre_bank_switch,
286 	.post_bank_switch = generic_post_bank_switch,
287 	.read_ping_status = cdns_read_ping_status,
288 	.get_device_num =  intel_get_device_num_ida,
289 	.put_device_num = intel_put_device_num_ida,
290 	.new_peripheral_assigned = generic_new_peripheral_assigned,
291 };
292 
293 /*
294  * probe and init (aux_dev_id argument is required by function prototype but not used)
295  */
296 static int intel_link_probe(struct auxiliary_device *auxdev,
297 			    const struct auxiliary_device_id *aux_dev_id)
298 
299 {
300 	struct device *dev = &auxdev->dev;
301 	struct sdw_intel_link_dev *ldev = auxiliary_dev_to_sdw_intel_link_dev(auxdev);
302 	struct sdw_intel *sdw;
303 	struct sdw_cdns *cdns;
304 	struct sdw_bus *bus;
305 	int ret;
306 
307 	sdw = devm_kzalloc(dev, sizeof(*sdw), GFP_KERNEL);
308 	if (!sdw)
309 		return -ENOMEM;
310 
311 	cdns = &sdw->cdns;
312 	bus = &cdns->bus;
313 
314 	sdw->instance = auxdev->id;
315 	sdw->link_res = &ldev->link_res;
316 	cdns->dev = dev;
317 	cdns->registers = sdw->link_res->registers;
318 	cdns->ip_offset = sdw->link_res->ip_offset;
319 	cdns->instance = sdw->instance;
320 	cdns->msg_count = 0;
321 
322 	/* single controller for all SoundWire links */
323 	bus->controller_id = 0;
324 
325 	bus->link_id = auxdev->id;
326 	bus->clk_stop_timeout = 1;
327 
328 	/*
329 	 * paranoia check: make sure ACPI-reported number of links is aligned with
330 	 * hardware capabilities.
331 	 */
332 	ret = sdw_intel_get_link_count(sdw);
333 	if (ret < 0) {
334 		dev_err(dev, "%s: sdw_intel_get_link_count failed: %d\n", __func__, ret);
335 		return ret;
336 	}
337 	if (ret <= sdw->instance) {
338 		dev_err(dev, "%s: invalid link id %d, link count %d\n", __func__, auxdev->id, ret);
339 		return -EINVAL;
340 	}
341 
342 	sdw_cdns_probe(cdns);
343 
344 	/* Set ops */
345 	bus->ops = &sdw_intel_ops;
346 
347 	/* set driver data, accessed by snd_soc_dai_get_drvdata() */
348 	auxiliary_set_drvdata(auxdev, cdns);
349 
350 	/* use generic bandwidth allocation algorithm */
351 	sdw->cdns.bus.compute_params = sdw_compute_params;
352 
353 	/* avoid resuming from pm_runtime suspend if it's not required */
354 	dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
355 
356 	ret = sdw_bus_master_add(bus, dev, dev->fwnode);
357 	if (ret) {
358 		dev_err(dev, "sdw_bus_master_add fail: %d\n", ret);
359 		return ret;
360 	}
361 
362 	if (bus->prop.hw_disabled)
363 		dev_info(dev,
364 			 "SoundWire master %d is disabled, will be ignored\n",
365 			 bus->link_id);
366 	/*
367 	 * Ignore BIOS err_threshold, it's a really bad idea when dealing
368 	 * with multiple hardware synchronized links
369 	 */
370 	bus->prop.err_threshold = 0;
371 
372 	return 0;
373 }
374 
375 int intel_link_startup(struct auxiliary_device *auxdev)
376 {
377 	struct device *dev = &auxdev->dev;
378 	struct sdw_cdns *cdns = auxiliary_get_drvdata(auxdev);
379 	struct sdw_intel *sdw = cdns_to_intel(cdns);
380 	struct sdw_bus *bus = &cdns->bus;
381 	int link_flags;
382 	bool multi_link;
383 	u32 clock_stop_quirks;
384 	int ret;
385 
386 	if (bus->prop.hw_disabled) {
387 		dev_info(dev,
388 			 "SoundWire master %d is disabled, ignoring\n",
389 			 sdw->instance);
390 		return 0;
391 	}
392 
393 	link_flags = md_flags >> (bus->link_id * 8);
394 	multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
395 	if (!multi_link) {
396 		dev_dbg(dev, "Multi-link is disabled\n");
397 	} else {
398 		/*
399 		 * hardware-based synchronization is required regardless
400 		 * of the number of segments used by a stream: SSP-based
401 		 * synchronization is gated by gsync when the multi-master
402 		 * mode is set.
403 		 */
404 		bus->hw_sync_min_links = 1;
405 	}
406 	bus->multi_link = multi_link;
407 
408 	/* Initialize shim, controller */
409 	ret = sdw_intel_link_power_up(sdw);
410 	if (ret)
411 		goto err_init;
412 
413 	/* Register DAIs */
414 	ret = sdw_intel_register_dai(sdw);
415 	if (ret) {
416 		dev_err(dev, "DAI registration failed: %d\n", ret);
417 		goto err_power_up;
418 	}
419 
420 	sdw_intel_debugfs_init(sdw);
421 
422 	/* Enable runtime PM */
423 	if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME)) {
424 		pm_runtime_set_autosuspend_delay(dev,
425 						 INTEL_MASTER_SUSPEND_DELAY_MS);
426 		pm_runtime_use_autosuspend(dev);
427 		pm_runtime_mark_last_busy(dev);
428 
429 		pm_runtime_set_active(dev);
430 		pm_runtime_enable(dev);
431 
432 		pm_runtime_resume(bus->dev);
433 	}
434 
435 	/* start bus */
436 	ret = sdw_intel_start_bus(sdw);
437 	if (ret) {
438 		dev_err(dev, "bus start failed: %d\n", ret);
439 		goto err_pm_runtime;
440 	}
441 
442 	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
443 	if (clock_stop_quirks & SDW_INTEL_CLK_STOP_NOT_ALLOWED) {
444 		/*
445 		 * To keep the clock running we need to prevent
446 		 * pm_runtime suspend from happening by increasing the
447 		 * reference count.
448 		 * This quirk is specified by the parent PCI device in
449 		 * case of specific latency requirements. It will have
450 		 * no effect if pm_runtime is disabled by the user via
451 		 * a module parameter for testing purposes.
452 		 */
453 		pm_runtime_get_noresume(dev);
454 	}
455 
456 	/*
457 	 * The runtime PM status of Slave devices is "Unsupported"
458 	 * until they report as ATTACHED. If they don't, e.g. because
459 	 * there are no Slave devices populated or if the power-on is
460 	 * delayed or dependent on a power switch, the Master will
461 	 * remain active and prevent its parent from suspending.
462 	 *
463 	 * Conditionally force the pm_runtime core to re-evaluate the
464 	 * Master status in the absence of any Slave activity. A quirk
465 	 * is provided to e.g. deal with Slaves that may be powered on
466 	 * with a delay. A more complete solution would require the
467 	 * definition of Master properties.
468 	 */
469 	if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) {
470 		pm_runtime_mark_last_busy(bus->dev);
471 		pm_runtime_mark_last_busy(dev);
472 		pm_runtime_idle(dev);
473 	}
474 
475 	sdw->startup_done = true;
476 	return 0;
477 
478 err_pm_runtime:
479 	if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME))
480 		pm_runtime_disable(dev);
481 err_power_up:
482 	sdw_intel_link_power_down(sdw);
483 err_init:
484 	return ret;
485 }
486 
487 static void intel_link_remove(struct auxiliary_device *auxdev)
488 {
489 	struct sdw_cdns *cdns = auxiliary_get_drvdata(auxdev);
490 	struct sdw_intel *sdw = cdns_to_intel(cdns);
491 	struct sdw_bus *bus = &cdns->bus;
492 
493 	/*
494 	 * Since pm_runtime is already disabled, we don't decrease
495 	 * the refcount when the clock_stop_quirk is
496 	 * SDW_INTEL_CLK_STOP_NOT_ALLOWED
497 	 */
498 	if (!bus->prop.hw_disabled) {
499 		sdw_intel_debugfs_exit(sdw);
500 		cancel_delayed_work_sync(&cdns->attach_dwork);
501 		sdw_cdns_enable_interrupt(cdns, false);
502 	}
503 	sdw_bus_master_delete(bus);
504 }
505 
506 int intel_link_process_wakeen_event(struct auxiliary_device *auxdev)
507 {
508 	struct device *dev = &auxdev->dev;
509 	struct sdw_intel *sdw;
510 	struct sdw_bus *bus;
511 
512 	sdw = auxiliary_get_drvdata(auxdev);
513 	bus = &sdw->cdns.bus;
514 
515 	if (bus->prop.hw_disabled || !sdw->startup_done) {
516 		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
517 			bus->link_id);
518 		return 0;
519 	}
520 
521 	if (!sdw_intel_shim_check_wake(sdw))
522 		return 0;
523 
524 	/* disable WAKEEN interrupt ASAP to prevent interrupt flood */
525 	sdw_intel_shim_wake(sdw, false);
526 
527 	/*
528 	 * resume the Master, which will generate a bus reset and result in
529 	 * Slaves re-attaching and be re-enumerated. The SoundWire physical
530 	 * device which generated the wake will trigger an interrupt, which
531 	 * will in turn cause the corresponding Linux Slave device to be
532 	 * resumed and the Slave codec driver to check the status.
533 	 */
534 	pm_request_resume(dev);
535 
536 	return 0;
537 }
538 
539 /*
540  * PM calls
541  */
542 
543 int intel_resume_child_device(struct device *dev, void *data)
544 {
545 	int ret;
546 	struct sdw_slave *slave = dev_to_sdw_dev(dev);
547 
548 	if (!slave->probed) {
549 		dev_dbg(dev, "skipping device, no probed driver\n");
550 		return 0;
551 	}
552 	if (!slave->dev_num_sticky) {
553 		dev_dbg(dev, "skipping device, never detected on bus\n");
554 		return 0;
555 	}
556 
557 	ret = pm_runtime_resume(dev);
558 	if (ret < 0) {
559 		dev_err(dev, "%s: pm_runtime_resume failed: %d\n", __func__, ret);
560 		return ret;
561 	}
562 
563 	return 0;
564 }
565 
566 static int __maybe_unused intel_pm_prepare(struct device *dev)
567 {
568 	struct sdw_cdns *cdns = dev_get_drvdata(dev);
569 	struct sdw_intel *sdw = cdns_to_intel(cdns);
570 	struct sdw_bus *bus = &cdns->bus;
571 	u32 clock_stop_quirks;
572 	int ret;
573 
574 	if (bus->prop.hw_disabled || !sdw->startup_done) {
575 		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
576 			bus->link_id);
577 		return 0;
578 	}
579 
580 	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
581 
582 	if (pm_runtime_suspended(dev) &&
583 	    pm_runtime_suspended(dev->parent) &&
584 	    ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
585 	     !clock_stop_quirks)) {
586 		/*
587 		 * if we've enabled clock stop, and the parent is suspended, the SHIM registers
588 		 * are not accessible and the shim wake cannot be disabled.
589 		 * The only solution is to resume the entire bus to full power
590 		 */
591 
592 		/*
593 		 * If any operation in this block fails, we keep going since we don't want
594 		 * to prevent system suspend from happening and errors should be recoverable
595 		 * on resume.
596 		 */
597 
598 		/*
599 		 * first resume the device for this link. This will also by construction
600 		 * resume the PCI parent device.
601 		 */
602 		ret = pm_runtime_resume(dev);
603 		if (ret < 0) {
604 			dev_err(dev, "%s: pm_runtime_resume failed: %d\n", __func__, ret);
605 			return 0;
606 		}
607 
608 		/*
609 		 * Continue resuming the entire bus (parent + child devices) to exit
610 		 * the clock stop mode. If there are no devices connected on this link
611 		 * this is a no-op.
612 		 * The resume to full power could have been implemented with a .prepare
613 		 * step in SoundWire codec drivers. This would however require a lot
614 		 * of code to handle an Intel-specific corner case. It is simpler in
615 		 * practice to add a loop at the link level.
616 		 */
617 		ret = device_for_each_child(bus->dev, NULL, intel_resume_child_device);
618 
619 		if (ret < 0)
620 			dev_err(dev, "%s: intel_resume_child_device failed: %d\n", __func__, ret);
621 	}
622 
623 	return 0;
624 }
625 
626 static int __maybe_unused intel_suspend(struct device *dev)
627 {
628 	struct sdw_cdns *cdns = dev_get_drvdata(dev);
629 	struct sdw_intel *sdw = cdns_to_intel(cdns);
630 	struct sdw_bus *bus = &cdns->bus;
631 	u32 clock_stop_quirks;
632 	int ret;
633 
634 	if (bus->prop.hw_disabled || !sdw->startup_done) {
635 		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
636 			bus->link_id);
637 		return 0;
638 	}
639 
640 	if (pm_runtime_suspended(dev)) {
641 		dev_dbg(dev, "pm_runtime status: suspended\n");
642 
643 		clock_stop_quirks = sdw->link_res->clock_stop_quirks;
644 
645 		if ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
646 		    !clock_stop_quirks) {
647 
648 			if (pm_runtime_suspended(dev->parent)) {
649 				/*
650 				 * paranoia check: this should not happen with the .prepare
651 				 * resume to full power
652 				 */
653 				dev_err(dev, "%s: invalid config: parent is suspended\n", __func__);
654 			} else {
655 				sdw_intel_shim_wake(sdw, false);
656 			}
657 		}
658 
659 		return 0;
660 	}
661 
662 	ret = sdw_intel_stop_bus(sdw, false);
663 	if (ret < 0) {
664 		dev_err(dev, "%s: cannot stop bus: %d\n", __func__, ret);
665 		return ret;
666 	}
667 
668 	return 0;
669 }
670 
671 static int __maybe_unused intel_suspend_runtime(struct device *dev)
672 {
673 	struct sdw_cdns *cdns = dev_get_drvdata(dev);
674 	struct sdw_intel *sdw = cdns_to_intel(cdns);
675 	struct sdw_bus *bus = &cdns->bus;
676 	u32 clock_stop_quirks;
677 	int ret;
678 
679 	if (bus->prop.hw_disabled || !sdw->startup_done) {
680 		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
681 			bus->link_id);
682 		return 0;
683 	}
684 
685 	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
686 
687 	if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
688 		ret = sdw_intel_stop_bus(sdw, false);
689 		if (ret < 0) {
690 			dev_err(dev, "%s: cannot stop bus during teardown: %d\n",
691 				__func__, ret);
692 			return ret;
693 		}
694 	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET || !clock_stop_quirks) {
695 		ret = sdw_intel_stop_bus(sdw, true);
696 		if (ret < 0) {
697 			dev_err(dev, "%s: cannot stop bus during clock_stop: %d\n",
698 				__func__, ret);
699 			return ret;
700 		}
701 	} else {
702 		dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
703 			__func__, clock_stop_quirks);
704 		ret = -EINVAL;
705 	}
706 
707 	return ret;
708 }
709 
710 static int __maybe_unused intel_resume(struct device *dev)
711 {
712 	struct sdw_cdns *cdns = dev_get_drvdata(dev);
713 	struct sdw_intel *sdw = cdns_to_intel(cdns);
714 	struct sdw_bus *bus = &cdns->bus;
715 	int link_flags;
716 	int ret;
717 
718 	if (bus->prop.hw_disabled || !sdw->startup_done) {
719 		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
720 			bus->link_id);
721 		return 0;
722 	}
723 
724 	if (pm_runtime_suspended(dev)) {
725 		dev_dbg(dev, "pm_runtime status was suspended, forcing active\n");
726 
727 		/* follow required sequence from runtime_pm.rst */
728 		pm_runtime_disable(dev);
729 		pm_runtime_set_active(dev);
730 		pm_runtime_mark_last_busy(dev);
731 		pm_runtime_enable(dev);
732 
733 		pm_runtime_resume(bus->dev);
734 
735 		link_flags = md_flags >> (bus->link_id * 8);
736 
737 		if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
738 			pm_runtime_idle(dev);
739 	}
740 
741 	ret = sdw_intel_link_power_up(sdw);
742 	if (ret) {
743 		dev_err(dev, "%s failed: %d\n", __func__, ret);
744 		return ret;
745 	}
746 
747 	/*
748 	 * make sure all Slaves are tagged as UNATTACHED and provide
749 	 * reason for reinitialization
750 	 */
751 	sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
752 
753 	ret = sdw_intel_start_bus(sdw);
754 	if (ret < 0) {
755 		dev_err(dev, "cannot start bus during resume\n");
756 		sdw_intel_link_power_down(sdw);
757 		return ret;
758 	}
759 
760 	/*
761 	 * after system resume, the pm_runtime suspend() may kick in
762 	 * during the enumeration, before any children device force the
763 	 * master device to remain active.  Using pm_runtime_get()
764 	 * routines is not really possible, since it'd prevent the
765 	 * master from suspending.
766 	 * A reasonable compromise is to update the pm_runtime
767 	 * counters and delay the pm_runtime suspend by several
768 	 * seconds, by when all enumeration should be complete.
769 	 */
770 	pm_runtime_mark_last_busy(bus->dev);
771 	pm_runtime_mark_last_busy(dev);
772 
773 	return 0;
774 }
775 
776 static int __maybe_unused intel_resume_runtime(struct device *dev)
777 {
778 	struct sdw_cdns *cdns = dev_get_drvdata(dev);
779 	struct sdw_intel *sdw = cdns_to_intel(cdns);
780 	struct sdw_bus *bus = &cdns->bus;
781 	u32 clock_stop_quirks;
782 	int ret;
783 
784 	if (bus->prop.hw_disabled || !sdw->startup_done) {
785 		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
786 			bus->link_id);
787 		return 0;
788 	}
789 
790 	/* unconditionally disable WAKEEN interrupt */
791 	sdw_intel_shim_wake(sdw, false);
792 
793 	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
794 
795 	if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
796 		ret = sdw_intel_link_power_up(sdw);
797 		if (ret) {
798 			dev_err(dev, "%s: power_up failed after teardown: %d\n", __func__, ret);
799 			return ret;
800 		}
801 
802 		/*
803 		 * make sure all Slaves are tagged as UNATTACHED and provide
804 		 * reason for reinitialization
805 		 */
806 		sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
807 
808 		ret = sdw_intel_start_bus(sdw);
809 		if (ret < 0) {
810 			dev_err(dev, "%s: cannot start bus after teardown: %d\n", __func__, ret);
811 			sdw_intel_link_power_down(sdw);
812 			return ret;
813 		}
814 
815 	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
816 		ret = sdw_intel_link_power_up(sdw);
817 		if (ret) {
818 			dev_err(dev, "%s: power_up failed after bus reset: %d\n", __func__, ret);
819 			return ret;
820 		}
821 
822 		ret = sdw_intel_start_bus_after_reset(sdw);
823 		if (ret < 0) {
824 			dev_err(dev, "%s: cannot start bus after reset: %d\n", __func__, ret);
825 			sdw_intel_link_power_down(sdw);
826 			return ret;
827 		}
828 	} else if (!clock_stop_quirks) {
829 
830 		sdw_intel_check_clock_stop(sdw);
831 
832 		ret = sdw_intel_link_power_up(sdw);
833 		if (ret) {
834 			dev_err(dev, "%s: power_up failed: %d\n", __func__, ret);
835 			return ret;
836 		}
837 
838 		ret = sdw_intel_start_bus_after_clock_stop(sdw);
839 		if (ret < 0) {
840 			dev_err(dev, "%s: cannot start bus after clock stop: %d\n", __func__, ret);
841 			sdw_intel_link_power_down(sdw);
842 			return ret;
843 		}
844 	} else {
845 		dev_err(dev, "%s: clock_stop_quirks %x unsupported\n",
846 			__func__, clock_stop_quirks);
847 		ret = -EINVAL;
848 	}
849 
850 	return ret;
851 }
852 
853 static const struct dev_pm_ops intel_pm = {
854 	.prepare = intel_pm_prepare,
855 	SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
856 	SET_RUNTIME_PM_OPS(intel_suspend_runtime, intel_resume_runtime, NULL)
857 };
858 
859 static const struct auxiliary_device_id intel_link_id_table[] = {
860 	{ .name = "soundwire_intel.link" },
861 	{},
862 };
863 MODULE_DEVICE_TABLE(auxiliary, intel_link_id_table);
864 
865 static struct auxiliary_driver sdw_intel_drv = {
866 	.probe = intel_link_probe,
867 	.remove = intel_link_remove,
868 	.driver = {
869 		/* auxiliary_driver_register() sets .name to be the modname */
870 		.pm = &intel_pm,
871 	},
872 	.id_table = intel_link_id_table
873 };
874 module_auxiliary_driver(sdw_intel_drv);
875 
876 MODULE_LICENSE("Dual BSD/GPL");
877 MODULE_DESCRIPTION("Intel Soundwire Link Driver");
878