blob: ec733f683f34f645838ff9a0b684b532fac71a6a [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* ChromeOS EC multi-function device
*
* Copyright (C) 2012 Google, Inc
*
* The ChromeOS EC multi function device is used to mux all the requests
* to the EC device for its multiple features: keyboard controller,
* battery charging and regulator control, firmware update.
*/
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/slab.h>
#include <linux/suspend.h>
#include "cros_ec.h"
static struct cros_ec_platform ec_p = {
.ec_name = CROS_EC_DEV_NAME,
.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_EC_INDEX),
};
static struct cros_ec_platform pd_p = {
.ec_name = CROS_EC_DEV_PD_NAME,
.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX),
};
/**
* cros_ec_irq_handler() - top half part of the interrupt handler
* @irq: IRQ id
* @data: (ec_dev) Device with events to process.
*
* Return: Wakeup the bottom half
*/
static irqreturn_t cros_ec_irq_handler(int irq, void *data)
{
struct cros_ec_device *ec_dev = data;
ec_dev->last_event_time = cros_ec_get_time_ns();
return IRQ_WAKE_THREAD;
}
/**
* cros_ec_handle_event() - process and forward pending events on EC
* @ec_dev: Device with events to process.
*
* Call this function in a loop when the kernel is notified that the EC has
* pending events.
*
* Return: true if more events are still pending and this function should be
* called again.
*/
static bool cros_ec_handle_event(struct cros_ec_device *ec_dev)
{
bool wake_event;
bool ec_has_more_events;
int ret;
ret = cros_ec_get_next_event(ec_dev, &wake_event, &ec_has_more_events);
/*
* Signal only if wake host events or any interrupt if
* cros_ec_get_next_event() returned an error (default value for
* wake_event is true)
*/
if (wake_event && device_may_wakeup(ec_dev->dev))
pm_wakeup_event(ec_dev->dev, 0);
if (ret > 0)
blocking_notifier_call_chain(&ec_dev->event_notifier,
0, ec_dev);
return ec_has_more_events;
}
/**
* cros_ec_irq_thread() - bottom half part of the interrupt handler
* @irq: IRQ id
* @data: (ec_dev) Device with events to process.
*
* Return: Interrupt handled.
*/
irqreturn_t cros_ec_irq_thread(int irq, void *data)
{
struct cros_ec_device *ec_dev = data;
bool ec_has_more_events;
do {
ec_has_more_events = cros_ec_handle_event(ec_dev);
} while (ec_has_more_events);
return IRQ_HANDLED;
}
EXPORT_SYMBOL(cros_ec_irq_thread);
static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
{
int ret;
struct {
struct cros_ec_command msg;
union {
struct ec_params_host_sleep_event req0;
struct ec_params_host_sleep_event_v1 req1;
struct ec_response_host_sleep_event_v1 resp1;
} u;
} __packed buf;
memset(&buf, 0, sizeof(buf));
if (ec_dev->host_sleep_v1) {
buf.u.req1.sleep_event = sleep_event;
buf.u.req1.suspend_params.sleep_timeout_ms =
ec_dev->suspend_timeout_ms;
buf.msg.outsize = sizeof(buf.u.req1);
if ((sleep_event == HOST_SLEEP_EVENT_S3_RESUME) ||
(sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME))
buf.msg.insize = sizeof(buf.u.resp1);
buf.msg.version = 1;
} else {
buf.u.req0.sleep_event = sleep_event;
buf.msg.outsize = sizeof(buf.u.req0);
}
buf.msg.command = EC_CMD_HOST_SLEEP_EVENT;
ret = cros_ec_cmd_xfer_status(ec_dev, &buf.msg);
/* Report failure to transition to system wide suspend with a warning. */
if (ret >= 0 && ec_dev->host_sleep_v1 &&
(sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME ||
sleep_event == HOST_SLEEP_EVENT_S3_RESUME)) {
ec_dev->last_resume_result =
buf.u.resp1.resume_response.sleep_transitions;
WARN_ONCE(buf.u.resp1.resume_response.sleep_transitions &
EC_HOST_RESUME_SLEEP_TIMEOUT,
"EC detected sleep transition timeout. Total sleep transitions: %d",
buf.u.resp1.resume_response.sleep_transitions &
EC_HOST_RESUME_SLEEP_TRANSITIONS_MASK);
}
return ret;
}
static int cros_ec_ready_event(struct notifier_block *nb,
unsigned long queued_during_suspend,
void *_notify)
{
struct cros_ec_device *ec_dev = container_of(nb, struct cros_ec_device,
notifier_ready);
u32 host_event = cros_ec_get_host_event(ec_dev);
if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INTERFACE_READY)) {
mutex_lock(&ec_dev->lock);
cros_ec_query_all(ec_dev);
mutex_unlock(&ec_dev->lock);
return NOTIFY_OK;
}
return NOTIFY_DONE;
}
/**
* cros_ec_register() - Register a new ChromeOS EC, using the provided info.
* @ec_dev: Device to register.
*
* Before calling this, allocate a pointer to a new device and then fill
* in all the fields up to the --private-- marker.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_register(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
int err = 0;
BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
ec_dev->max_request = sizeof(struct ec_params_hello);
ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
ec_dev->max_passthru = 0;
ec_dev->ec = NULL;
ec_dev->pd = NULL;
ec_dev->suspend_timeout_ms = EC_HOST_SLEEP_TIMEOUT_DEFAULT;
ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
if (!ec_dev->din)
return -ENOMEM;
ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
if (!ec_dev->dout)
return -ENOMEM;
mutex_init(&ec_dev->lock);
err = cros_ec_query_all(ec_dev);
if (err) {
dev_err(dev, "Cannot identify the EC: error %d\n", err);
return err;
}
if (ec_dev->irq > 0) {
err = devm_request_threaded_irq(dev, ec_dev->irq,
cros_ec_irq_handler,
cros_ec_irq_thread,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"chromeos-ec", ec_dev);
if (err) {
dev_err(dev, "Failed to request IRQ %d: %d\n",
ec_dev->irq, err);
return err;
}
}
/* Register a platform device for the main EC instance */
ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev",
PLATFORM_DEVID_AUTO, &ec_p,
sizeof(struct cros_ec_platform));
if (IS_ERR(ec_dev->ec)) {
dev_err(ec_dev->dev,
"Failed to create CrOS EC platform device\n");
return PTR_ERR(ec_dev->ec);
}
if (ec_dev->max_passthru) {
/*
* Register a platform device for the PD behind the main EC.
* We make the following assumptions:
* - behind an EC, we have a pd
* - only one device added.
* - the EC is responsive at init time (it is not true for a
* sensor hub).
*/
ec_dev->pd = platform_device_register_data(ec_dev->dev,
"cros-ec-dev",
PLATFORM_DEVID_AUTO, &pd_p,
sizeof(struct cros_ec_platform));
if (IS_ERR(ec_dev->pd)) {
dev_err(ec_dev->dev,
"Failed to create CrOS PD platform device\n");
err = PTR_ERR(ec_dev->pd);
goto exit;
}
}
if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
err = devm_of_platform_populate(dev);
if (err) {
dev_err(dev, "Failed to register sub-devices\n");
goto exit;
}
}
/*
* Clear sleep event - this will fail harmlessly on platforms that
* don't implement the sleep event host command.
*/
err = cros_ec_sleep_event(ec_dev, 0);
if (err < 0)
dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec\n",
err);
if (ec_dev->mkbp_event_supported) {
/*
* Register the notifier for EC_HOST_EVENT_INTERFACE_READY
* event.
*/
ec_dev->notifier_ready.notifier_call = cros_ec_ready_event;
err = blocking_notifier_chain_register(&ec_dev->event_notifier,
&ec_dev->notifier_ready);
if (err)
goto exit;
}
dev_info(dev, "Chrome EC device registered\n");
/*
* Unlock EC that may be waiting for AP to process MKBP events.
* If the AP takes to long to answer, the EC would stop sending events.
*/
if (ec_dev->mkbp_event_supported)
cros_ec_irq_thread(0, ec_dev);
return 0;
exit:
platform_device_unregister(ec_dev->ec);
platform_device_unregister(ec_dev->pd);
return err;
}
EXPORT_SYMBOL(cros_ec_register);
/**
* cros_ec_unregister() - Remove a ChromeOS EC.
* @ec_dev: Device to unregister.
*
* Call this to deregister a ChromeOS EC, then clean up any private data.
*
* Return: 0 on success or negative error code.
*/
void cros_ec_unregister(struct cros_ec_device *ec_dev)
{
if (ec_dev->pd)
platform_device_unregister(ec_dev->pd);
platform_device_unregister(ec_dev->ec);
}
EXPORT_SYMBOL(cros_ec_unregister);
#ifdef CONFIG_PM_SLEEP
/**
* cros_ec_suspend() - Handle a suspend operation for the ChromeOS EC device.
* @ec_dev: Device to suspend.
*
* This can be called by drivers to handle a suspend event.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_suspend(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
int ret;
u8 sleep_event;
sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
HOST_SLEEP_EVENT_S3_SUSPEND :
HOST_SLEEP_EVENT_S0IX_SUSPEND;
ret = cros_ec_sleep_event(ec_dev, sleep_event);
if (ret < 0)
dev_dbg(ec_dev->dev, "Error %d sending suspend event to ec\n",
ret);
if (device_may_wakeup(dev))
ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
else
ec_dev->wake_enabled = false;
disable_irq(ec_dev->irq);
ec_dev->suspended = true;
return 0;
}
EXPORT_SYMBOL(cros_ec_suspend);
static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev)
{
bool wake_event;
while (ec_dev->mkbp_event_supported &&
cros_ec_get_next_event(ec_dev, &wake_event, NULL) > 0) {
blocking_notifier_call_chain(&ec_dev->event_notifier,
1, ec_dev);
if (wake_event && device_may_wakeup(ec_dev->dev))
pm_wakeup_event(ec_dev->dev, 0);
}
}
/**
* cros_ec_resume() - Handle a resume operation for the ChromeOS EC device.
* @ec_dev: Device to resume.
*
* This can be called by drivers to handle a resume event.
*
* Return: 0 on success or negative error code.
*/
int cros_ec_resume(struct cros_ec_device *ec_dev)
{
int ret;
u8 sleep_event;
ec_dev->suspended = false;
enable_irq(ec_dev->irq);
sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ?
HOST_SLEEP_EVENT_S3_RESUME :
HOST_SLEEP_EVENT_S0IX_RESUME;
ret = cros_ec_sleep_event(ec_dev, sleep_event);
if (ret < 0)
dev_dbg(ec_dev->dev, "Error %d sending resume event to ec\n",
ret);
if (ec_dev->wake_enabled)
disable_irq_wake(ec_dev->irq);
/*
* Let the mfd devices know about events that occur during
* suspend. This way the clients know what to do with them.
*/
cros_ec_report_events_during_suspend(ec_dev);
return 0;
}
EXPORT_SYMBOL(cros_ec_resume);
#endif
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ChromeOS EC core driver");