linux/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
Srinivas Pandruvada f1664eaace iio: hid-sensor-trigger: Fix the race with user space powering up sensors
It has been reported for a while that with iio-sensor-proxy service the
rotation only works after one suspend/resume cycle. This required a wait
in the systemd unit file to avoid race. I found a Yoga 900 where I could
reproduce this.

The problem scenerio is:
- During sensor driver init, enable run time PM and also set a
  auto-suspend for 3 seconds.
	This result in one runtime resume. But there is a check to avoid
a powerup in this sequence, but rpm is active
- User space iio-sensor-proxy tries to power up the sensor. Since rpm is
  active it will simply return. But sensors were not actually
powered up in the prior sequence, so actaully the sensors will not work
- After 3 seconds the auto suspend kicks

If we add a wait in systemd service file to fire iio-sensor-proxy after
3 seconds, then now everything will work as the runtime resume will
actually powerup the sensor as this is a user request.

To avoid this:
- Remove the check to match user requested state, this will cause a
  brief powerup, but if the iio-sensor-proxy starts immediately it will
still work as the sensors are ON.
- Also move the autosuspend delay to place when user requested turn off
  of sensors, like after user finished raw read or buffer disable

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: Bastien Nocera <hadess@hadess.net>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2017-08-20 15:21:48 +01:00

336 lines
9.4 KiB
C

/*
* HID Sensors Driver
* Copyright (c) 2012, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/hid-sensor-hub.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/iio/buffer.h>
#include <linux/iio/sysfs.h>
#include "hid-sensor-trigger.h"
static ssize_t _hid_sensor_set_report_latency(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
int integer, fract, ret;
int latency;
ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
if (ret)
return ret;
latency = integer * 1000 + fract / 1000;
ret = hid_sensor_set_report_latency(attrb, latency);
if (ret < 0)
return len;
attrb->latency_ms = hid_sensor_get_report_latency(attrb);
return len;
}
static ssize_t _hid_sensor_get_report_latency(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
int latency;
latency = hid_sensor_get_report_latency(attrb);
if (latency < 0)
return latency;
return sprintf(buf, "%d.%06u\n", latency / 1000, (latency % 1000) * 1000);
}
static ssize_t _hid_sensor_get_fifo_state(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
int latency;
latency = hid_sensor_get_report_latency(attrb);
if (latency < 0)
return latency;
return sprintf(buf, "%d\n", !!latency);
}
static IIO_DEVICE_ATTR(hwfifo_timeout, 0644,
_hid_sensor_get_report_latency,
_hid_sensor_set_report_latency, 0);
static IIO_DEVICE_ATTR(hwfifo_enabled, 0444,
_hid_sensor_get_fifo_state, NULL, 0);
static const struct attribute *hid_sensor_fifo_attributes[] = {
&iio_dev_attr_hwfifo_timeout.dev_attr.attr,
&iio_dev_attr_hwfifo_enabled.dev_attr.attr,
NULL,
};
static void hid_sensor_setup_batch_mode(struct iio_dev *indio_dev,
struct hid_sensor_common *st)
{
if (!hid_sensor_batch_mode_supported(st))
return;
iio_buffer_set_attrs(indio_dev->buffer, hid_sensor_fifo_attributes);
}
static int _hid_sensor_power_state(struct hid_sensor_common *st, bool state)
{
int state_val;
int report_val;
s32 poll_value = 0;
if (state) {
if (sensor_hub_device_open(st->hsdev))
return -EIO;
atomic_inc(&st->data_ready);
state_val = hid_sensor_get_usage_index(st->hsdev,
st->power_state.report_id,
st->power_state.index,
HID_USAGE_SENSOR_PROP_POWER_STATE_D0_FULL_POWER_ENUM);
report_val = hid_sensor_get_usage_index(st->hsdev,
st->report_state.report_id,
st->report_state.index,
HID_USAGE_SENSOR_PROP_REPORTING_STATE_ALL_EVENTS_ENUM);
poll_value = hid_sensor_read_poll_value(st);
} else {
int val;
val = atomic_dec_if_positive(&st->data_ready);
if (val < 0)
return 0;
sensor_hub_device_close(st->hsdev);
state_val = hid_sensor_get_usage_index(st->hsdev,
st->power_state.report_id,
st->power_state.index,
HID_USAGE_SENSOR_PROP_POWER_STATE_D4_POWER_OFF_ENUM);
report_val = hid_sensor_get_usage_index(st->hsdev,
st->report_state.report_id,
st->report_state.index,
HID_USAGE_SENSOR_PROP_REPORTING_STATE_NO_EVENTS_ENUM);
}
if (state_val >= 0) {
state_val += st->power_state.logical_minimum;
sensor_hub_set_feature(st->hsdev, st->power_state.report_id,
st->power_state.index, sizeof(state_val),
&state_val);
}
if (report_val >= 0) {
report_val += st->report_state.logical_minimum;
sensor_hub_set_feature(st->hsdev, st->report_state.report_id,
st->report_state.index,
sizeof(report_val),
&report_val);
}
pr_debug("HID_SENSOR %s set power_state %d report_state %d\n",
st->pdev->name, state_val, report_val);
sensor_hub_get_feature(st->hsdev, st->power_state.report_id,
st->power_state.index,
sizeof(state_val), &state_val);
if (state && poll_value)
msleep_interruptible(poll_value * 2);
return 0;
}
EXPORT_SYMBOL(hid_sensor_power_state);
int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
{
#ifdef CONFIG_PM
int ret;
atomic_set(&st->user_requested_state, state);
if (state)
ret = pm_runtime_get_sync(&st->pdev->dev);
else {
pm_runtime_mark_last_busy(&st->pdev->dev);
pm_runtime_use_autosuspend(&st->pdev->dev);
ret = pm_runtime_put_autosuspend(&st->pdev->dev);
}
if (ret < 0) {
if (state)
pm_runtime_put_noidle(&st->pdev->dev);
return ret;
}
return 0;
#else
atomic_set(&st->user_requested_state, state);
return _hid_sensor_power_state(st, state);
#endif
}
static void hid_sensor_set_power_work(struct work_struct *work)
{
struct hid_sensor_common *attrb = container_of(work,
struct hid_sensor_common,
work);
if (attrb->poll_interval >= 0)
sensor_hub_set_feature(attrb->hsdev, attrb->poll.report_id,
attrb->poll.index,
sizeof(attrb->poll_interval),
&attrb->poll_interval);
if (attrb->raw_hystersis >= 0)
sensor_hub_set_feature(attrb->hsdev,
attrb->sensitivity.report_id,
attrb->sensitivity.index,
sizeof(attrb->raw_hystersis),
&attrb->raw_hystersis);
if (attrb->latency_ms > 0)
hid_sensor_set_report_latency(attrb, attrb->latency_ms);
_hid_sensor_power_state(attrb, true);
}
static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig,
bool state)
{
return hid_sensor_power_state(iio_trigger_get_drvdata(trig), state);
}
void hid_sensor_remove_trigger(struct hid_sensor_common *attrb)
{
pm_runtime_disable(&attrb->pdev->dev);
pm_runtime_set_suspended(&attrb->pdev->dev);
pm_runtime_put_noidle(&attrb->pdev->dev);
cancel_work_sync(&attrb->work);
iio_trigger_unregister(attrb->trigger);
iio_trigger_free(attrb->trigger);
}
EXPORT_SYMBOL(hid_sensor_remove_trigger);
static const struct iio_trigger_ops hid_sensor_trigger_ops = {
.owner = THIS_MODULE,
.set_trigger_state = &hid_sensor_data_rdy_trigger_set_state,
};
int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name,
struct hid_sensor_common *attrb)
{
int ret;
struct iio_trigger *trig;
trig = iio_trigger_alloc("%s-dev%d", name, indio_dev->id);
if (trig == NULL) {
dev_err(&indio_dev->dev, "Trigger Allocate Failed\n");
ret = -ENOMEM;
goto error_ret;
}
trig->dev.parent = indio_dev->dev.parent;
iio_trigger_set_drvdata(trig, attrb);
trig->ops = &hid_sensor_trigger_ops;
ret = iio_trigger_register(trig);
if (ret) {
dev_err(&indio_dev->dev, "Trigger Register Failed\n");
goto error_free_trig;
}
attrb->trigger = trig;
indio_dev->trig = iio_trigger_get(trig);
hid_sensor_setup_batch_mode(indio_dev, attrb);
ret = pm_runtime_set_active(&indio_dev->dev);
if (ret)
goto error_unreg_trigger;
iio_device_set_drvdata(indio_dev, attrb);
INIT_WORK(&attrb->work, hid_sensor_set_power_work);
pm_suspend_ignore_children(&attrb->pdev->dev, true);
pm_runtime_enable(&attrb->pdev->dev);
/* Default to 3 seconds, but can be changed from sysfs */
pm_runtime_set_autosuspend_delay(&attrb->pdev->dev,
3000);
return ret;
error_unreg_trigger:
iio_trigger_unregister(trig);
error_free_trig:
iio_trigger_free(trig);
error_ret:
return ret;
}
EXPORT_SYMBOL(hid_sensor_setup_trigger);
static int __maybe_unused hid_sensor_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
return _hid_sensor_power_state(attrb, false);
}
static int __maybe_unused hid_sensor_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
schedule_work(&attrb->work);
return 0;
}
static int __maybe_unused hid_sensor_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
struct hid_sensor_common *attrb = iio_device_get_drvdata(indio_dev);
return _hid_sensor_power_state(attrb, true);
}
const struct dev_pm_ops hid_sensor_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(hid_sensor_suspend, hid_sensor_resume)
SET_RUNTIME_PM_OPS(hid_sensor_suspend,
hid_sensor_runtime_resume, NULL)
};
EXPORT_SYMBOL(hid_sensor_pm_ops);
MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
MODULE_DESCRIPTION("HID Sensor trigger processing");
MODULE_LICENSE("GPL");