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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * ChromeOS EC multi-function device
  4 *
  5 * Copyright (C) 2012 Google, Inc
  6 *
  7 * The ChromeOS EC multi function device is used to mux all the requests
  8 * to the EC device for its multiple features: keyboard controller,
  9 * battery charging and regulator control, firmware update.
 10 */
 11
 
 12#include <linux/interrupt.h>
 
 13#include <linux/module.h>
 14#include <linux/of_platform.h>
 15#include <linux/platform_device.h>
 16#include <linux/platform_data/cros_ec_commands.h>
 17#include <linux/platform_data/cros_ec_proto.h>
 18#include <linux/slab.h>
 19#include <linux/suspend.h>
 20
 21#include "cros_ec.h"
 22
 
 
 
 23static struct cros_ec_platform ec_p = {
 24	.ec_name = CROS_EC_DEV_NAME,
 25	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_EC_INDEX),
 26};
 27
 28static struct cros_ec_platform pd_p = {
 29	.ec_name = CROS_EC_DEV_PD_NAME,
 30	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX),
 31};
 32
 33/**
 34 * cros_ec_irq_handler() - top half part of the interrupt handler
 35 * @irq: IRQ id
 36 * @data: (ec_dev) Device with events to process.
 37 *
 38 * Return: Wakeup the bottom half
 39 */
 40static irqreturn_t cros_ec_irq_handler(int irq, void *data)
 41{
 42	struct cros_ec_device *ec_dev = data;
 43
 44	ec_dev->last_event_time = cros_ec_get_time_ns();
 45
 46	return IRQ_WAKE_THREAD;
 47}
 48
 49/**
 50 * cros_ec_handle_event() - process and forward pending events on EC
 51 * @ec_dev: Device with events to process.
 52 *
 53 * Call this function in a loop when the kernel is notified that the EC has
 54 * pending events.
 55 *
 56 * Return: true if more events are still pending and this function should be
 57 * called again.
 58 */
 59static bool cros_ec_handle_event(struct cros_ec_device *ec_dev)
 60{
 61	bool wake_event;
 62	bool ec_has_more_events;
 63	int ret;
 64
 65	ret = cros_ec_get_next_event(ec_dev, &wake_event, &ec_has_more_events);
 66
 67	/*
 68	 * Signal only if wake host events or any interrupt if
 69	 * cros_ec_get_next_event() returned an error (default value for
 70	 * wake_event is true)
 71	 */
 72	if (wake_event && device_may_wakeup(ec_dev->dev))
 73		pm_wakeup_event(ec_dev->dev, 0);
 74
 75	if (ret > 0)
 76		blocking_notifier_call_chain(&ec_dev->event_notifier,
 77					     0, ec_dev);
 78
 79	return ec_has_more_events;
 80}
 81
 82/**
 83 * cros_ec_irq_thread() - bottom half part of the interrupt handler
 84 * @irq: IRQ id
 85 * @data: (ec_dev) Device with events to process.
 86 *
 87 * Return: Interrupt handled.
 88 */
 89irqreturn_t cros_ec_irq_thread(int irq, void *data)
 90{
 91	struct cros_ec_device *ec_dev = data;
 92	bool ec_has_more_events;
 93
 94	do {
 95		ec_has_more_events = cros_ec_handle_event(ec_dev);
 96	} while (ec_has_more_events);
 97
 98	return IRQ_HANDLED;
 99}
100EXPORT_SYMBOL(cros_ec_irq_thread);
101
102static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
103{
104	int ret;
105	struct {
106		struct cros_ec_command msg;
107		union {
108			struct ec_params_host_sleep_event req0;
109			struct ec_params_host_sleep_event_v1 req1;
110			struct ec_response_host_sleep_event_v1 resp1;
111		} u;
112	} __packed buf;
113
114	memset(&buf, 0, sizeof(buf));
115
116	if (ec_dev->host_sleep_v1) {
117		buf.u.req1.sleep_event = sleep_event;
118		buf.u.req1.suspend_params.sleep_timeout_ms =
119				ec_dev->suspend_timeout_ms;
120
121		buf.msg.outsize = sizeof(buf.u.req1);
122		if ((sleep_event == HOST_SLEEP_EVENT_S3_RESUME) ||
123		    (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME))
124			buf.msg.insize = sizeof(buf.u.resp1);
125
126		buf.msg.version = 1;
127
128	} else {
129		buf.u.req0.sleep_event = sleep_event;
130		buf.msg.outsize = sizeof(buf.u.req0);
131	}
132
133	buf.msg.command = EC_CMD_HOST_SLEEP_EVENT;
134
135	ret = cros_ec_cmd_xfer_status(ec_dev, &buf.msg);
136	/* Report failure to transition to system wide suspend with a warning. */
 
137	if (ret >= 0 && ec_dev->host_sleep_v1 &&
138	    (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME ||
139	     sleep_event == HOST_SLEEP_EVENT_S3_RESUME)) {
140		ec_dev->last_resume_result =
141			buf.u.resp1.resume_response.sleep_transitions;
142
143		WARN_ONCE(buf.u.resp1.resume_response.sleep_transitions &
144			  EC_HOST_RESUME_SLEEP_TIMEOUT,
145			  "EC detected sleep transition timeout. Total sleep transitions: %d",
146			  buf.u.resp1.resume_response.sleep_transitions &
147			  EC_HOST_RESUME_SLEEP_TRANSITIONS_MASK);
148	}
149
150	return ret;
151}
152
153static int cros_ec_ready_event(struct notifier_block *nb,
154			       unsigned long queued_during_suspend,
155			       void *_notify)
156{
157	struct cros_ec_device *ec_dev = container_of(nb, struct cros_ec_device,
158						     notifier_ready);
159	u32 host_event = cros_ec_get_host_event(ec_dev);
160
161	if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) {
162		mutex_lock(&ec_dev->lock);
163		cros_ec_query_all(ec_dev);
164		mutex_unlock(&ec_dev->lock);
165		return NOTIFY_OK;
166	}
167
168	return NOTIFY_DONE;
169}
170
171/**
172 * cros_ec_register() - Register a new ChromeOS EC, using the provided info.
173 * @ec_dev: Device to register.
174 *
175 * Before calling this, allocate a pointer to a new device and then fill
176 * in all the fields up to the --private-- marker.
177 *
178 * Return: 0 on success or negative error code.
179 */
180int cros_ec_register(struct cros_ec_device *ec_dev)
181{
182	struct device *dev = ec_dev->dev;
183	int err = 0;
184
185	BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
186	BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->panic_notifier);
187
188	ec_dev->max_request = sizeof(struct ec_params_hello);
189	ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
190	ec_dev->max_passthru = 0;
191	ec_dev->ec = NULL;
192	ec_dev->pd = NULL;
193	ec_dev->suspend_timeout_ms = EC_HOST_SLEEP_TIMEOUT_DEFAULT;
194
195	ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
196	if (!ec_dev->din)
197		return -ENOMEM;
198
199	ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
200	if (!ec_dev->dout)
201		return -ENOMEM;
202
203	lockdep_register_key(&ec_dev->lockdep_key);
204	mutex_init(&ec_dev->lock);
205	lockdep_set_class(&ec_dev->lock, &ec_dev->lockdep_key);
206
207	err = cros_ec_query_all(ec_dev);
208	if (err) {
209		dev_err(dev, "Cannot identify the EC: error %d\n", err);
210		goto exit;
211	}
212
213	if (ec_dev->irq > 0) {
214		err = devm_request_threaded_irq(dev, ec_dev->irq,
215						cros_ec_irq_handler,
216						cros_ec_irq_thread,
217						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
218						"chromeos-ec", ec_dev);
219		if (err) {
220			dev_err(dev, "Failed to request IRQ %d: %d\n",
221				ec_dev->irq, err);
222			goto exit;
223		}
224	}
225
226	/* Register a platform device for the main EC instance */
227	ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev",
228					PLATFORM_DEVID_AUTO, &ec_p,
229					sizeof(struct cros_ec_platform));
230	if (IS_ERR(ec_dev->ec)) {
231		dev_err(ec_dev->dev,
232			"Failed to create CrOS EC platform device\n");
233		err = PTR_ERR(ec_dev->ec);
234		goto exit;
235	}
236
237	if (ec_dev->max_passthru) {
238		/*
239		 * Register a platform device for the PD behind the main EC.
240		 * We make the following assumptions:
241		 * - behind an EC, we have a pd
242		 * - only one device added.
243		 * - the EC is responsive at init time (it is not true for a
244		 *   sensor hub).
245		 */
246		ec_dev->pd = platform_device_register_data(ec_dev->dev,
247					"cros-ec-dev",
248					PLATFORM_DEVID_AUTO, &pd_p,
249					sizeof(struct cros_ec_platform));
250		if (IS_ERR(ec_dev->pd)) {
251			dev_err(ec_dev->dev,
252				"Failed to create CrOS PD platform device\n");
253			err = PTR_ERR(ec_dev->pd);
254			goto exit;
255		}
256	}
257
258	if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
259		err = devm_of_platform_populate(dev);
260		if (err) {
 
 
261			dev_err(dev, "Failed to register sub-devices\n");
262			goto exit;
263		}
264	}
265
266	/*
267	 * Clear sleep event - this will fail harmlessly on platforms that
268	 * don't implement the sleep event host command.
269	 */
270	err = cros_ec_sleep_event(ec_dev, 0);
271	if (err < 0)
272		dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec\n",
273			err);
274
275	if (ec_dev->mkbp_event_supported) {
276		/*
277		 * Register the notifier for EC_HOST_EVENT_INTERFACE_READY
278		 * event.
279		 */
280		ec_dev->notifier_ready.notifier_call = cros_ec_ready_event;
281		err = blocking_notifier_chain_register(&ec_dev->event_notifier,
282						      &ec_dev->notifier_ready);
283		if (err)
284			goto exit;
285	}
286
287	dev_info(dev, "Chrome EC device registered\n");
288
289	/*
290	 * Unlock EC that may be waiting for AP to process MKBP events.
291	 * If the AP takes to long to answer, the EC would stop sending events.
292	 */
293	if (ec_dev->mkbp_event_supported)
294		cros_ec_irq_thread(0, ec_dev);
295
296	return 0;
297exit:
298	platform_device_unregister(ec_dev->ec);
299	platform_device_unregister(ec_dev->pd);
300	mutex_destroy(&ec_dev->lock);
301	lockdep_unregister_key(&ec_dev->lockdep_key);
302	return err;
303}
304EXPORT_SYMBOL(cros_ec_register);
305
306/**
307 * cros_ec_unregister() - Remove a ChromeOS EC.
308 * @ec_dev: Device to unregister.
309 *
310 * Call this to deregister a ChromeOS EC, then clean up any private data.
311 *
312 * Return: 0 on success or negative error code.
313 */
314void cros_ec_unregister(struct cros_ec_device *ec_dev)
315{
316	platform_device_unregister(ec_dev->pd);
 
317	platform_device_unregister(ec_dev->ec);
318	mutex_destroy(&ec_dev->lock);
319	lockdep_unregister_key(&ec_dev->lockdep_key);
320}
321EXPORT_SYMBOL(cros_ec_unregister);
322
323#ifdef CONFIG_PM_SLEEP
324static void cros_ec_send_suspend_event(struct cros_ec_device *ec_dev)
 
 
 
 
 
 
 
 
325{
 
326	int ret;
327	u8 sleep_event;
328
329	sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
330		      HOST_SLEEP_EVENT_S3_SUSPEND :
331		      HOST_SLEEP_EVENT_S0IX_SUSPEND;
332
333	ret = cros_ec_sleep_event(ec_dev, sleep_event);
334	if (ret < 0)
335		dev_dbg(ec_dev->dev, "Error %d sending suspend event to ec\n",
336			ret);
337}
338
339/**
340 * cros_ec_suspend_prepare() - Handle a suspend prepare operation for the ChromeOS EC device.
341 * @ec_dev: Device to suspend.
342 *
343 * This can be called by drivers to handle a suspend prepare stage of suspend.
344 *
345 * Return: 0 always.
346 */
347int cros_ec_suspend_prepare(struct cros_ec_device *ec_dev)
348{
349	cros_ec_send_suspend_event(ec_dev);
350	return 0;
351}
352EXPORT_SYMBOL(cros_ec_suspend_prepare);
353
354static void cros_ec_disable_irq(struct cros_ec_device *ec_dev)
355{
356	struct device *dev = ec_dev->dev;
357	if (device_may_wakeup(dev))
358		ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
359	else
360		ec_dev->wake_enabled = false;
361
362	disable_irq(ec_dev->irq);
 
363	ec_dev->suspended = true;
364}
365
366/**
367 * cros_ec_suspend_late() - Handle a suspend late operation for the ChromeOS EC device.
368 * @ec_dev: Device to suspend.
369 *
370 * This can be called by drivers to handle a suspend late stage of suspend.
371 *
372 * Return: 0 always.
373 */
374int cros_ec_suspend_late(struct cros_ec_device *ec_dev)
375{
376	cros_ec_disable_irq(ec_dev);
377	return 0;
378}
379EXPORT_SYMBOL(cros_ec_suspend_late);
380
381/**
382 * cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
383 * @ec_dev: Device to suspend.
384 *
385 * This can be called by drivers to handle a suspend event.
386 *
387 * Return: 0 always.
388 */
389int cros_ec_suspend(struct cros_ec_device *ec_dev)
390{
391	cros_ec_suspend_prepare(ec_dev);
392	cros_ec_suspend_late(ec_dev);
393	return 0;
394}
395EXPORT_SYMBOL(cros_ec_suspend);
396
397static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev)
398{
399	bool wake_event;
400
401	while (ec_dev->mkbp_event_supported &&
402	       cros_ec_get_next_event(ec_dev, &wake_event, NULL) > 0) {
403		blocking_notifier_call_chain(&ec_dev->event_notifier,
404					     1, ec_dev);
405
406		if (wake_event && device_may_wakeup(ec_dev->dev))
407			pm_wakeup_event(ec_dev->dev, 0);
408	}
409}
410
411static void cros_ec_send_resume_event(struct cros_ec_device *ec_dev)
 
 
 
 
 
 
 
 
412{
413	int ret;
414	u8 sleep_event;
415
 
 
 
416	sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
417		      HOST_SLEEP_EVENT_S3_RESUME :
418		      HOST_SLEEP_EVENT_S0IX_RESUME;
419
420	ret = cros_ec_sleep_event(ec_dev, sleep_event);
421	if (ret < 0)
422		dev_dbg(ec_dev->dev, "Error %d sending resume event to ec\n",
423			ret);
424}
425
426/**
427 * cros_ec_resume_complete() - Handle a resume complete operation for the ChromeOS EC device.
428 * @ec_dev: Device to resume.
429 *
430 * This can be called by drivers to handle a resume complete stage of resume.
431 */
432void cros_ec_resume_complete(struct cros_ec_device *ec_dev)
433{
434	cros_ec_send_resume_event(ec_dev);
435
 
 
 
 
436	/*
437	 * Let the mfd devices know about events that occur during
438	 * suspend. This way the clients know what to do with them.
439	 */
440	cros_ec_report_events_during_suspend(ec_dev);
441}
442EXPORT_SYMBOL(cros_ec_resume_complete);
443
444static void cros_ec_enable_irq(struct cros_ec_device *ec_dev)
445{
446	ec_dev->suspended = false;
447	enable_irq(ec_dev->irq);
448
449	if (ec_dev->wake_enabled)
450		disable_irq_wake(ec_dev->irq);
451}
452
453/**
454 * cros_ec_resume_early() - Handle a resume early operation for the ChromeOS EC device.
455 * @ec_dev: Device to resume.
456 *
457 * This can be called by drivers to handle a resume early stage of resume.
458 *
459 * Return: 0 always.
460 */
461int cros_ec_resume_early(struct cros_ec_device *ec_dev)
462{
463	cros_ec_enable_irq(ec_dev);
464	return 0;
465}
466EXPORT_SYMBOL(cros_ec_resume_early);
467
468/**
469 * cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
470 * @ec_dev: Device to resume.
471 *
472 * This can be called by drivers to handle a resume event.
473 *
474 * Return: 0 always.
475 */
476int cros_ec_resume(struct cros_ec_device *ec_dev)
477{
478	cros_ec_resume_early(ec_dev);
479	cros_ec_resume_complete(ec_dev);
480	return 0;
481}
482EXPORT_SYMBOL(cros_ec_resume);
483
484#endif
485
486MODULE_LICENSE("GPL");
487MODULE_DESCRIPTION("ChromeOS EC core driver");
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * ChromeOS EC multi-function device
  4 *
  5 * Copyright (C) 2012 Google, Inc
  6 *
  7 * The ChromeOS EC multi function device is used to mux all the requests
  8 * to the EC device for its multiple features: keyboard controller,
  9 * battery charging and regulator control, firmware update.
 10 */
 11
 12#include <linux/of_platform.h>
 13#include <linux/interrupt.h>
 14#include <linux/slab.h>
 15#include <linux/module.h>
 
 
 16#include <linux/platform_data/cros_ec_commands.h>
 17#include <linux/platform_data/cros_ec_proto.h>
 
 18#include <linux/suspend.h>
 19
 20#include "cros_ec.h"
 21
 22#define CROS_EC_DEV_EC_INDEX 0
 23#define CROS_EC_DEV_PD_INDEX 1
 24
 25static struct cros_ec_platform ec_p = {
 26	.ec_name = CROS_EC_DEV_NAME,
 27	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_EC_INDEX),
 28};
 29
 30static struct cros_ec_platform pd_p = {
 31	.ec_name = CROS_EC_DEV_PD_NAME,
 32	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX),
 33};
 34
 35/**
 36 * cros_ec_irq_handler() - top half part of the interrupt handler
 37 * @irq: IRQ id
 38 * @data: (ec_dev) Device with events to process.
 39 *
 40 * Return: Wakeup the bottom half
 41 */
 42static irqreturn_t cros_ec_irq_handler(int irq, void *data)
 43{
 44	struct cros_ec_device *ec_dev = data;
 45
 46	ec_dev->last_event_time = cros_ec_get_time_ns();
 47
 48	return IRQ_WAKE_THREAD;
 49}
 50
 51/**
 52 * cros_ec_handle_event() - process and forward pending events on EC
 53 * @ec_dev: Device with events to process.
 54 *
 55 * Call this function in a loop when the kernel is notified that the EC has
 56 * pending events.
 57 *
 58 * Return: true if more events are still pending and this function should be
 59 * called again.
 60 */
 61static bool cros_ec_handle_event(struct cros_ec_device *ec_dev)
 62{
 63	bool wake_event;
 64	bool ec_has_more_events;
 65	int ret;
 66
 67	ret = cros_ec_get_next_event(ec_dev, &wake_event, &ec_has_more_events);
 68
 69	/*
 70	 * Signal only if wake host events or any interrupt if
 71	 * cros_ec_get_next_event() returned an error (default value for
 72	 * wake_event is true)
 73	 */
 74	if (wake_event && device_may_wakeup(ec_dev->dev))
 75		pm_wakeup_event(ec_dev->dev, 0);
 76
 77	if (ret > 0)
 78		blocking_notifier_call_chain(&ec_dev->event_notifier,
 79					     0, ec_dev);
 80
 81	return ec_has_more_events;
 82}
 83
 84/**
 85 * cros_ec_irq_thread() - bottom half part of the interrupt handler
 86 * @irq: IRQ id
 87 * @data: (ec_dev) Device with events to process.
 88 *
 89 * Return: Interrupt handled.
 90 */
 91irqreturn_t cros_ec_irq_thread(int irq, void *data)
 92{
 93	struct cros_ec_device *ec_dev = data;
 94	bool ec_has_more_events;
 95
 96	do {
 97		ec_has_more_events = cros_ec_handle_event(ec_dev);
 98	} while (ec_has_more_events);
 99
100	return IRQ_HANDLED;
101}
102EXPORT_SYMBOL(cros_ec_irq_thread);
103
104static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
105{
106	int ret;
107	struct {
108		struct cros_ec_command msg;
109		union {
110			struct ec_params_host_sleep_event req0;
111			struct ec_params_host_sleep_event_v1 req1;
112			struct ec_response_host_sleep_event_v1 resp1;
113		} u;
114	} __packed buf;
115
116	memset(&buf, 0, sizeof(buf));
117
118	if (ec_dev->host_sleep_v1) {
119		buf.u.req1.sleep_event = sleep_event;
120		buf.u.req1.suspend_params.sleep_timeout_ms =
121				EC_HOST_SLEEP_TIMEOUT_DEFAULT;
122
123		buf.msg.outsize = sizeof(buf.u.req1);
124		if ((sleep_event == HOST_SLEEP_EVENT_S3_RESUME) ||
125		    (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME))
126			buf.msg.insize = sizeof(buf.u.resp1);
127
128		buf.msg.version = 1;
129
130	} else {
131		buf.u.req0.sleep_event = sleep_event;
132		buf.msg.outsize = sizeof(buf.u.req0);
133	}
134
135	buf.msg.command = EC_CMD_HOST_SLEEP_EVENT;
136
137	ret = cros_ec_cmd_xfer_status(ec_dev, &buf.msg);
138
139	/* For now, report failure to transition to S0ix with a warning. */
140	if (ret >= 0 && ec_dev->host_sleep_v1 &&
141	    (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME)) {
 
142		ec_dev->last_resume_result =
143			buf.u.resp1.resume_response.sleep_transitions;
144
145		WARN_ONCE(buf.u.resp1.resume_response.sleep_transitions &
146			  EC_HOST_RESUME_SLEEP_TIMEOUT,
147			  "EC detected sleep transition timeout. Total slp_s0 transitions: %d",
148			  buf.u.resp1.resume_response.sleep_transitions &
149			  EC_HOST_RESUME_SLEEP_TRANSITIONS_MASK);
150	}
151
152	return ret;
153}
154
155static int cros_ec_ready_event(struct notifier_block *nb,
156			       unsigned long queued_during_suspend,
157			       void *_notify)
158{
159	struct cros_ec_device *ec_dev = container_of(nb, struct cros_ec_device,
160						     notifier_ready);
161	u32 host_event = cros_ec_get_host_event(ec_dev);
162
163	if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) {
164		mutex_lock(&ec_dev->lock);
165		cros_ec_query_all(ec_dev);
166		mutex_unlock(&ec_dev->lock);
167		return NOTIFY_OK;
168	}
169
170	return NOTIFY_DONE;
171}
172
173/**
174 * cros_ec_register() - Register a new ChromeOS EC, using the provided info.
175 * @ec_dev: Device to register.
176 *
177 * Before calling this, allocate a pointer to a new device and then fill
178 * in all the fields up to the --private-- marker.
179 *
180 * Return: 0 on success or negative error code.
181 */
182int cros_ec_register(struct cros_ec_device *ec_dev)
183{
184	struct device *dev = ec_dev->dev;
185	int err = 0;
186
187	BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
 
188
189	ec_dev->max_request = sizeof(struct ec_params_hello);
190	ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
191	ec_dev->max_passthru = 0;
 
 
 
192
193	ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
194	if (!ec_dev->din)
195		return -ENOMEM;
196
197	ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
198	if (!ec_dev->dout)
199		return -ENOMEM;
200
 
201	mutex_init(&ec_dev->lock);
 
202
203	err = cros_ec_query_all(ec_dev);
204	if (err) {
205		dev_err(dev, "Cannot identify the EC: error %d\n", err);
206		return err;
207	}
208
209	if (ec_dev->irq > 0) {
210		err = devm_request_threaded_irq(dev, ec_dev->irq,
211						cros_ec_irq_handler,
212						cros_ec_irq_thread,
213						IRQF_TRIGGER_LOW | IRQF_ONESHOT,
214						"chromeos-ec", ec_dev);
215		if (err) {
216			dev_err(dev, "Failed to request IRQ %d: %d",
217				ec_dev->irq, err);
218			return err;
219		}
220	}
221
222	/* Register a platform device for the main EC instance */
223	ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev",
224					PLATFORM_DEVID_AUTO, &ec_p,
225					sizeof(struct cros_ec_platform));
226	if (IS_ERR(ec_dev->ec)) {
227		dev_err(ec_dev->dev,
228			"Failed to create CrOS EC platform device\n");
229		return PTR_ERR(ec_dev->ec);
 
230	}
231
232	if (ec_dev->max_passthru) {
233		/*
234		 * Register a platform device for the PD behind the main EC.
235		 * We make the following assumptions:
236		 * - behind an EC, we have a pd
237		 * - only one device added.
238		 * - the EC is responsive at init time (it is not true for a
239		 *   sensor hub).
240		 */
241		ec_dev->pd = platform_device_register_data(ec_dev->dev,
242					"cros-ec-dev",
243					PLATFORM_DEVID_AUTO, &pd_p,
244					sizeof(struct cros_ec_platform));
245		if (IS_ERR(ec_dev->pd)) {
246			dev_err(ec_dev->dev,
247				"Failed to create CrOS PD platform device\n");
248			platform_device_unregister(ec_dev->ec);
249			return PTR_ERR(ec_dev->pd);
250		}
251	}
252
253	if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
254		err = devm_of_platform_populate(dev);
255		if (err) {
256			platform_device_unregister(ec_dev->pd);
257			platform_device_unregister(ec_dev->ec);
258			dev_err(dev, "Failed to register sub-devices\n");
259			return err;
260		}
261	}
262
263	/*
264	 * Clear sleep event - this will fail harmlessly on platforms that
265	 * don't implement the sleep event host command.
266	 */
267	err = cros_ec_sleep_event(ec_dev, 0);
268	if (err < 0)
269		dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec",
270			err);
271
272	if (ec_dev->mkbp_event_supported) {
273		/*
274		 * Register the notifier for EC_HOST_EVENT_INTERFACE_READY
275		 * event.
276		 */
277		ec_dev->notifier_ready.notifier_call = cros_ec_ready_event;
278		err = blocking_notifier_chain_register(&ec_dev->event_notifier,
279						      &ec_dev->notifier_ready);
280		if (err)
281			return err;
282	}
283
284	dev_info(dev, "Chrome EC device registered\n");
285
286	/*
287	 * Unlock EC that may be waiting for AP to process MKBP events.
288	 * If the AP takes to long to answer, the EC would stop sending events.
289	 */
290	if (ec_dev->mkbp_event_supported)
291		cros_ec_irq_thread(0, ec_dev);
292
293	return 0;
 
 
 
 
 
 
294}
295EXPORT_SYMBOL(cros_ec_register);
296
297/**
298 * cros_ec_unregister() - Remove a ChromeOS EC.
299 * @ec_dev: Device to unregister.
300 *
301 * Call this to deregister a ChromeOS EC, then clean up any private data.
302 *
303 * Return: 0 on success or negative error code.
304 */
305int cros_ec_unregister(struct cros_ec_device *ec_dev)
306{
307	if (ec_dev->pd)
308		platform_device_unregister(ec_dev->pd);
309	platform_device_unregister(ec_dev->ec);
310
311	return 0;
312}
313EXPORT_SYMBOL(cros_ec_unregister);
314
315#ifdef CONFIG_PM_SLEEP
316/**
317 * cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
318 * @ec_dev: Device to suspend.
319 *
320 * This can be called by drivers to handle a suspend event.
321 *
322 * Return: 0 on success or negative error code.
323 */
324int cros_ec_suspend(struct cros_ec_device *ec_dev)
325{
326	struct device *dev = ec_dev->dev;
327	int ret;
328	u8 sleep_event;
329
330	sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
331		      HOST_SLEEP_EVENT_S3_SUSPEND :
332		      HOST_SLEEP_EVENT_S0IX_SUSPEND;
333
334	ret = cros_ec_sleep_event(ec_dev, sleep_event);
335	if (ret < 0)
336		dev_dbg(ec_dev->dev, "Error %d sending suspend event to ec",
337			ret);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
338
 
 
 
339	if (device_may_wakeup(dev))
340		ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
 
 
341
342	disable_irq(ec_dev->irq);
343	ec_dev->was_wake_device = ec_dev->wake_enabled;
344	ec_dev->suspended = true;
 
345
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
346	return 0;
347}
348EXPORT_SYMBOL(cros_ec_suspend);
349
350static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev)
351{
 
 
352	while (ec_dev->mkbp_event_supported &&
353	       cros_ec_get_next_event(ec_dev, NULL, NULL) > 0)
354		blocking_notifier_call_chain(&ec_dev->event_notifier,
355					     1, ec_dev);
 
 
 
 
356}
357
358/**
359 * cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
360 * @ec_dev: Device to resume.
361 *
362 * This can be called by drivers to handle a resume event.
363 *
364 * Return: 0 on success or negative error code.
365 */
366int cros_ec_resume(struct cros_ec_device *ec_dev)
367{
368	int ret;
369	u8 sleep_event;
370
371	ec_dev->suspended = false;
372	enable_irq(ec_dev->irq);
373
374	sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
375		      HOST_SLEEP_EVENT_S3_RESUME :
376		      HOST_SLEEP_EVENT_S0IX_RESUME;
377
378	ret = cros_ec_sleep_event(ec_dev, sleep_event);
379	if (ret < 0)
380		dev_dbg(ec_dev->dev, "Error %d sending resume event to ec",
381			ret);
 
 
 
 
 
 
 
 
 
 
 
382
383	if (ec_dev->wake_enabled) {
384		disable_irq_wake(ec_dev->irq);
385		ec_dev->wake_enabled = 0;
386	}
387	/*
388	 * Let the mfd devices know about events that occur during
389	 * suspend. This way the clients know what to do with them.
390	 */
391	cros_ec_report_events_during_suspend(ec_dev);
 
 
392
 
 
 
 
 
 
 
 
393
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
394	return 0;
395}
396EXPORT_SYMBOL(cros_ec_resume);
397
398#endif
399
400MODULE_LICENSE("GPL");
401MODULE_DESCRIPTION("ChromeOS EC core driver");