1 // SPDX-License-Identifier: GPL-2.0-only
3 * ChromeOS EC multi-function device
5 * Copyright (C) 2012 Google, Inc
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.
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>
22 #define CROS_EC_DEV_EC_INDEX 0
23 #define CROS_EC_DEV_PD_INDEX 1
25 static 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),
30 static 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),
35 static irqreturn_t ec_irq_handler(int irq, void *data)
37 struct cros_ec_device *ec_dev = data;
39 ec_dev->last_event_time = cros_ec_get_time_ns();
41 return IRQ_WAKE_THREAD;
45 * cros_ec_handle_event() - process and forward pending events on EC
46 * @ec_dev: Device with events to process.
48 * Call this function in a loop when the kernel is notified that the EC has
51 * Return: true if more events are still pending and this function should be
54 bool cros_ec_handle_event(struct cros_ec_device *ec_dev)
57 bool ec_has_more_events;
60 ret = cros_ec_get_next_event(ec_dev, &wake_event, &ec_has_more_events);
63 * Signal only if wake host events or any interrupt if
64 * cros_ec_get_next_event() returned an error (default value for
67 if (wake_event && device_may_wakeup(ec_dev->dev))
68 pm_wakeup_event(ec_dev->dev, 0);
71 blocking_notifier_call_chain(&ec_dev->event_notifier,
74 return ec_has_more_events;
76 EXPORT_SYMBOL(cros_ec_handle_event);
78 static irqreturn_t ec_irq_thread(int irq, void *data)
80 struct cros_ec_device *ec_dev = data;
81 bool ec_has_more_events;
84 ec_has_more_events = cros_ec_handle_event(ec_dev);
85 } while (ec_has_more_events);
90 static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
94 struct cros_ec_command msg;
96 struct ec_params_host_sleep_event req0;
97 struct ec_params_host_sleep_event_v1 req1;
98 struct ec_response_host_sleep_event_v1 resp1;
102 memset(&buf, 0, sizeof(buf));
104 if (ec_dev->host_sleep_v1) {
105 buf.u.req1.sleep_event = sleep_event;
106 buf.u.req1.suspend_params.sleep_timeout_ms =
107 EC_HOST_SLEEP_TIMEOUT_DEFAULT;
109 buf.msg.outsize = sizeof(buf.u.req1);
110 if ((sleep_event == HOST_SLEEP_EVENT_S3_RESUME) ||
111 (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME))
112 buf.msg.insize = sizeof(buf.u.resp1);
117 buf.u.req0.sleep_event = sleep_event;
118 buf.msg.outsize = sizeof(buf.u.req0);
121 buf.msg.command = EC_CMD_HOST_SLEEP_EVENT;
123 ret = cros_ec_cmd_xfer(ec_dev, &buf.msg);
125 /* For now, report failure to transition to S0ix with a warning. */
126 if (ret >= 0 && ec_dev->host_sleep_v1 &&
127 (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME)) {
128 ec_dev->last_resume_result =
129 buf.u.resp1.resume_response.sleep_transitions;
131 WARN_ONCE(buf.u.resp1.resume_response.sleep_transitions &
132 EC_HOST_RESUME_SLEEP_TIMEOUT,
133 "EC detected sleep transition timeout. Total slp_s0 transitions: %d",
134 buf.u.resp1.resume_response.sleep_transitions &
135 EC_HOST_RESUME_SLEEP_TRANSITIONS_MASK);
142 * cros_ec_register() - Register a new ChromeOS EC, using the provided info.
143 * @ec_dev: Device to register.
145 * Before calling this, allocate a pointer to a new device and then fill
146 * in all the fields up to the --private-- marker.
148 * Return: 0 on success or negative error code.
150 int cros_ec_register(struct cros_ec_device *ec_dev)
152 struct device *dev = ec_dev->dev;
155 BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
157 ec_dev->max_request = sizeof(struct ec_params_hello);
158 ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
159 ec_dev->max_passthru = 0;
161 ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
165 ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
169 mutex_init(&ec_dev->lock);
171 err = cros_ec_query_all(ec_dev);
173 dev_err(dev, "Cannot identify the EC: error %d\n", err);
177 if (ec_dev->irq > 0) {
178 err = devm_request_threaded_irq(dev, ec_dev->irq,
181 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
182 "chromeos-ec", ec_dev);
184 dev_err(dev, "Failed to request IRQ %d: %d",
190 /* Register a platform device for the main EC instance */
191 ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev",
192 PLATFORM_DEVID_AUTO, &ec_p,
193 sizeof(struct cros_ec_platform));
194 if (IS_ERR(ec_dev->ec)) {
196 "Failed to create CrOS EC platform device\n");
197 return PTR_ERR(ec_dev->ec);
200 if (ec_dev->max_passthru) {
202 * Register a platform device for the PD behind the main EC.
203 * We make the following assumptions:
204 * - behind an EC, we have a pd
205 * - only one device added.
206 * - the EC is responsive at init time (it is not true for a
209 ec_dev->pd = platform_device_register_data(ec_dev->dev,
211 PLATFORM_DEVID_AUTO, &pd_p,
212 sizeof(struct cros_ec_platform));
213 if (IS_ERR(ec_dev->pd)) {
215 "Failed to create CrOS PD platform device\n");
216 platform_device_unregister(ec_dev->ec);
217 return PTR_ERR(ec_dev->pd);
221 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
222 err = devm_of_platform_populate(dev);
224 platform_device_unregister(ec_dev->pd);
225 platform_device_unregister(ec_dev->ec);
226 dev_err(dev, "Failed to register sub-devices\n");
232 * Clear sleep event - this will fail harmlessly on platforms that
233 * don't implement the sleep event host command.
235 err = cros_ec_sleep_event(ec_dev, 0);
237 dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec",
240 dev_info(dev, "Chrome EC device registered\n");
244 EXPORT_SYMBOL(cros_ec_register);
247 * cros_ec_unregister() - Remove a ChromeOS EC.
248 * @ec_dev: Device to unregister.
250 * Call this to deregister a ChromeOS EC, then clean up any private data.
252 * Return: 0 on success or negative error code.
254 int cros_ec_unregister(struct cros_ec_device *ec_dev)
257 platform_device_unregister(ec_dev->pd);
258 platform_device_unregister(ec_dev->ec);
262 EXPORT_SYMBOL(cros_ec_unregister);
264 #ifdef CONFIG_PM_SLEEP
266 * cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
267 * @ec_dev: Device to suspend.
269 * This can be called by drivers to handle a suspend event.
271 * Return: 0 on success or negative error code.
273 int cros_ec_suspend(struct cros_ec_device *ec_dev)
275 struct device *dev = ec_dev->dev;
279 sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
280 HOST_SLEEP_EVENT_S3_SUSPEND :
281 HOST_SLEEP_EVENT_S0IX_SUSPEND;
283 ret = cros_ec_sleep_event(ec_dev, sleep_event);
285 dev_dbg(ec_dev->dev, "Error %d sending suspend event to ec",
288 if (device_may_wakeup(dev))
289 ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
291 disable_irq(ec_dev->irq);
292 ec_dev->was_wake_device = ec_dev->wake_enabled;
293 ec_dev->suspended = true;
297 EXPORT_SYMBOL(cros_ec_suspend);
299 static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev)
301 while (ec_dev->mkbp_event_supported &&
302 cros_ec_get_next_event(ec_dev, NULL, NULL) > 0)
303 blocking_notifier_call_chain(&ec_dev->event_notifier,
308 * cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
309 * @ec_dev: Device to resume.
311 * This can be called by drivers to handle a resume event.
313 * Return: 0 on success or negative error code.
315 int cros_ec_resume(struct cros_ec_device *ec_dev)
320 ec_dev->suspended = false;
321 enable_irq(ec_dev->irq);
323 sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
324 HOST_SLEEP_EVENT_S3_RESUME :
325 HOST_SLEEP_EVENT_S0IX_RESUME;
327 ret = cros_ec_sleep_event(ec_dev, sleep_event);
329 dev_dbg(ec_dev->dev, "Error %d sending resume event to ec",
332 if (ec_dev->wake_enabled) {
333 disable_irq_wake(ec_dev->irq);
334 ec_dev->wake_enabled = 0;
337 * Let the mfd devices know about events that occur during
338 * suspend. This way the clients know what to do with them.
340 cros_ec_report_events_during_suspend(ec_dev);
345 EXPORT_SYMBOL(cros_ec_resume);
349 MODULE_LICENSE("GPL");
350 MODULE_DESCRIPTION("ChromeOS EC core driver");