ACPI / video: Add a parameter to not register the backlight sysfs interface

On some systems acpi-video backlight is broken in the sense that it cannot
control the brightness of the backlight, but it must still be called on
resume to power-up the backlight after resume.

This commit allows these systems to work by going through all the usual
backlight control moves, while not registering a sysfs backlight
interface.

This commit also adds a quirk enabling this parameter on Toshiba Portege
R830 systems which are known to be affected by this.

I wish there was a better way to deal with this, but we've been unable to
find one.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=21012
Link: https://bugs.freedesktop.org/show_bug.cgi?id=82634
Reported-and-tested-by: Sylvain Pasche <sylvain.pasche@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Hans de Goede 2015-06-09 10:32:25 +02:00 committed by Rafael J. Wysocki
parent 7f5c1882ad
commit 654a182d85

View file

@ -92,6 +92,9 @@ static int use_native_backlight_param = NATIVE_BACKLIGHT_NOT_SET;
module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);
static int use_native_backlight_dmi = NATIVE_BACKLIGHT_NOT_SET;
static int disable_backlight_sysfs_if = -1;
module_param(disable_backlight_sysfs_if, int, 0444);
static int register_count;
static struct mutex video_list_lock;
static struct list_head video_bus_head;
@ -431,6 +434,14 @@ static int __init video_enable_native_backlight(const struct dmi_system_id *d)
return 0;
}
static int __init video_disable_backlight_sysfs_if(
const struct dmi_system_id *d)
{
if (disable_backlight_sysfs_if == -1)
disable_backlight_sysfs_if = 1;
return 0;
}
static struct dmi_system_id video_dmi_table[] __initdata = {
/*
* Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
@ -592,6 +603,23 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
},
},
/*
* Some machines have a broken acpi-video interface for brightness
* control, but still need an acpi_video_device_lcd_set_level() call
* on resume to turn the backlight power on. We Enable backlight
* control on these systems, but do not register a backlight sysfs
* as brightness control does not work.
*/
{
/* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
.callback = video_disable_backlight_sysfs_if,
.ident = "Toshiba Portege R830",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
},
},
{}
};
@ -1391,7 +1419,7 @@ acpi_video_switch_brightness(struct work_struct *work)
int result = -EINVAL;
/* no warning message if acpi_backlight=vendor or a quirk is used */
if (!acpi_video_verify_backlight_support())
if (!device->backlight)
return;
if (!device->brightness)
@ -1666,8 +1694,9 @@ static int acpi_video_resume(struct notifier_block *nb,
for (i = 0; i < video->attached_count; i++) {
video_device = video->attached_array[i].bind_info;
if (video_device && video_device->backlight)
acpi_video_set_brightness(video_device->backlight);
if (video_device && video_device->brightness)
acpi_video_device_lcd_set_level(video_device,
video_device->brightness->curr);
}
return NOTIFY_OK;
@ -1716,6 +1745,10 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
result = acpi_video_init_brightness(device);
if (result)
return;
if (disable_backlight_sysfs_if > 0)
return;
name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
if (!name)
return;
@ -1738,8 +1771,10 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
&acpi_backlight_ops,
&props);
kfree(name);
if (IS_ERR(device->backlight))
if (IS_ERR(device->backlight)) {
device->backlight = NULL;
return;
}
/*
* Save current brightness level in case we have to restore it