hp_accel: do not call ACPI from invalid context
The LED on HP notebooks is connected through ACPI. That unfortunately
means that it needs to be delayed by using schedule_work() to avoid
calling the ACPI interpreter from an invalid context.
[akpm@linux-foundation.org: use flush_work() rather than sort-of reimplementing it]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: Éric Piel <eric.piel@tremplin-utc.net>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/hwmon/hp_accel.c b/drivers/hwmon/hp_accel.c
index 86a0f51..0370524 100644
--- a/drivers/hwmon/hp_accel.c
+++ b/drivers/hwmon/hp_accel.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 2007-2008 Yan Burman
* Copyright (C) 2008 Eric Piel
- * Copyright (C) 2008 Pavel Machek
+ * Copyright (C) 2008-2009 Pavel Machek
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -44,6 +44,36 @@
#define DRIVER_NAME "lis3lv02d"
#define ACPI_MDPS_CLASS "accelerometer"
+/* Delayed LEDs infrastructure ------------------------------------ */
+
+/* Special LED class that can defer work */
+struct delayed_led_classdev {
+ struct led_classdev led_classdev;
+ struct work_struct work;
+ enum led_brightness new_brightness;
+
+ unsigned int led; /* For driver */
+ void (*set_brightness)(struct delayed_led_classdev *data, enum led_brightness value);
+};
+
+static inline void delayed_set_status_worker(struct work_struct *work)
+{
+ struct delayed_led_classdev *data =
+ container_of(work, struct delayed_led_classdev, work);
+
+ data->set_brightness(data, data->new_brightness);
+}
+
+static inline void delayed_sysfs_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ struct delayed_led_classdev *data = container_of(led_cdev,
+ struct delayed_led_classdev, led_classdev);
+ data->new_brightness = brightness;
+ schedule_work(&data->work);
+}
+
+/* HP-specific accelerometer driver ------------------------------------ */
/* For automatic insertion of the module */
static struct acpi_device_id lis3lv02d_device_ids[] = {
@@ -155,28 +185,27 @@
*/
};
-static acpi_status hpled_acpi_write(acpi_handle handle, int reg)
+static void hpled_set(struct delayed_led_classdev *led_cdev, enum led_brightness value)
{
+ acpi_handle handle = adev.device->handle;
unsigned long long ret; /* Not used when writing */
union acpi_object in_obj[1];
struct acpi_object_list args = { 1, in_obj };
in_obj[0].type = ACPI_TYPE_INTEGER;
- in_obj[0].integer.value = reg;
+ in_obj[0].integer.value = !!value;
- return acpi_evaluate_integer(handle, "ALED", &args, &ret);
+ acpi_evaluate_integer(handle, "ALED", &args, &ret);
}
-static void hpled_set(struct led_classdev *led_cdev,
- enum led_brightness value)
-{
- hpled_acpi_write(adev.device->handle, !!value);
-}
-
-static struct led_classdev hpled_led = {
- .name = "hp:red:hddprotection",
- .default_trigger = "none",
- .brightness_set = hpled_set,
+static struct delayed_led_classdev hpled_led = {
+ .led_classdev = {
+ .name = "hp::hddprotect",
+ .default_trigger = "none",
+ .brightness_set = delayed_sysfs_set,
+ .flags = LED_CORE_SUSPENDRESUME,
+ },
+ .set_brightness = hpled_set,
};
static int lis3lv02d_add(struct acpi_device *device)
@@ -208,13 +237,15 @@
adev.ac = lis3lv02d_axis_normal;
}
- ret = led_classdev_register(NULL, &hpled_led);
+ INIT_WORK(&hpled_led.work, delayed_set_status_worker);
+ ret = led_classdev_register(NULL, &hpled_led.led_classdev);
if (ret)
return ret;
ret = lis3lv02d_init_device(&adev);
if (ret) {
- led_classdev_unregister(&hpled_led);
+ flush_work(&hpled_led.work);
+ led_classdev_unregister(&hpled_led.led_classdev);
return ret;
}
@@ -229,7 +260,8 @@
lis3lv02d_joystick_disable();
lis3lv02d_poweroff(device->handle);
- led_classdev_unregister(&hpled_led);
+ flush_work(&hpled_led.work);
+ led_classdev_unregister(&hpled_led.led_classdev);
return lis3lv02d_remove_fs();
}
@@ -240,7 +272,6 @@
{
/* make sure the device is off when we suspend */
lis3lv02d_poweroff(device->handle);
- led_classdev_suspend(&hpled_led);
return 0;
}
@@ -253,7 +284,6 @@
else
lis3lv02d_poweroff(device->handle);
mutex_unlock(&adev.lock);
- led_classdev_resume(&hpled_led);
return 0;
}
#else