linux/drivers/mfd/cros_ec.c
RaviChandra Sadineni 61cc15dac0 mfd: cros_ec: Check for mkbp events on resume only if supported.
Currently on every resume we check for mkbp events and notify the
clients. This helps in identifying the wakeup sources. But on devices
that do not support mkbp protocol, we might end up querying key state of
the keyboard in a loop which blocks the resume. Instead check for events
only if mkbp is supported.

Signed-off-by: RaviChandra Sadineni <ravisadineni@chromium.org>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-10-23 08:58:34 +01:00

263 lines
6.4 KiB
C

/*
* ChromeOS EC multi-function device
*
* Copyright (C) 2012 Google, Inc
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* 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/of_platform.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mfd/core.h>
#include <linux/mfd/cros_ec.h>
#include <linux/suspend.h>
#include <asm/unaligned.h>
#define CROS_EC_DEV_EC_INDEX 0
#define CROS_EC_DEV_PD_INDEX 1
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),
};
static const struct mfd_cell ec_cell = {
.name = "cros-ec-dev",
.platform_data = &ec_p,
.pdata_size = sizeof(ec_p),
};
static const struct mfd_cell ec_pd_cell = {
.name = "cros-ec-dev",
.platform_data = &pd_p,
.pdata_size = sizeof(pd_p),
};
static irqreturn_t ec_irq_thread(int irq, void *data)
{
struct cros_ec_device *ec_dev = data;
bool wake_event = true;
int ret;
ret = cros_ec_get_next_event(ec_dev, &wake_event);
/*
* 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 IRQ_HANDLED;
}
static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event)
{
struct {
struct cros_ec_command msg;
struct ec_params_host_sleep_event req;
} __packed buf;
memset(&buf, 0, sizeof(buf));
buf.req.sleep_event = sleep_event;
buf.msg.command = EC_CMD_HOST_SLEEP_EVENT;
buf.msg.version = 0;
buf.msg.outsize = sizeof(buf.req);
return cros_ec_cmd_xfer(ec_dev, &buf.msg);
}
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->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) {
err = devm_request_threaded_irq(dev, ec_dev->irq, NULL,
ec_irq_thread, IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"chromeos-ec", ec_dev);
if (err) {
dev_err(dev, "Failed to request IRQ %d: %d",
ec_dev->irq, err);
return err;
}
}
err = mfd_add_devices(ec_dev->dev, PLATFORM_DEVID_AUTO, &ec_cell, 1,
NULL, ec_dev->irq, NULL);
if (err) {
dev_err(dev,
"Failed to register Embedded Controller subdevice %d\n",
err);
return err;
}
if (ec_dev->max_passthru) {
/*
* Register a PD device as well on top of this device.
* 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.
*/
err = mfd_add_devices(ec_dev->dev, PLATFORM_DEVID_AUTO,
&ec_pd_cell, 1, NULL, ec_dev->irq, NULL);
if (err) {
dev_err(dev,
"Failed to register Power Delivery subdevice %d\n",
err);
return err;
}
}
if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
err = devm_of_platform_populate(dev);
if (err) {
mfd_remove_devices(dev);
dev_err(dev, "Failed to register sub-devices\n");
return err;
}
}
/*
* 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",
err);
dev_info(dev, "Chrome EC device registered\n");
return 0;
}
EXPORT_SYMBOL(cros_ec_register);
int cros_ec_remove(struct cros_ec_device *ec_dev)
{
mfd_remove_devices(ec_dev->dev);
return 0;
}
EXPORT_SYMBOL(cros_ec_remove);
#ifdef CONFIG_PM_SLEEP
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",
ret);
if (device_may_wakeup(dev))
ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
disable_irq(ec_dev->irq);
ec_dev->was_wake_device = ec_dev->wake_enabled;
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)
{
while (ec_dev->mkbp_event_supported &&
cros_ec_get_next_event(ec_dev, NULL) > 0)
blocking_notifier_call_chain(&ec_dev->event_notifier,
1, ec_dev);
}
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",
ret);
if (ec_dev->wake_enabled) {
disable_irq_wake(ec_dev->irq);
ec_dev->wake_enabled = 0;
}
/*
* 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");