Adds backlight sysfs support for acpi video driver.
signed-off-by: Luming Yu <[email protected]>
--
Kconfig | 2 -
video.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 70 insertions(+), 3 deletions(-)
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 3f7e9f3..196cb0a 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -106,7 +106,7 @@ config ACPI_BUTTON
config ACPI_VIDEO
tristate "Video"
- depends on X86
+ depends on X86 && BACKLIGHT_CLASS_DEVICE
help
This driver implement the ACPI Extensions For Display Adapters
for integrated graphics devices on motherboard, as specified in
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 53a9eb0..c83dd57 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -31,6 +31,7 @@ #include <linux/list.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
+#include <linux/backlight.h>
#include <asm/uaccess.h>
#include <acpi/acpi_bus.h>
@@ -55,6 +56,7 @@ #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0
#define ACPI_VIDEO_HEAD_INVALID (~0u - 1)
#define ACPI_VIDEO_HEAD_END (~0u)
+#define MAX_NAME_LEN 20
#define _COMPONENT ACPI_VIDEO_COMPONENT
ACPI_MODULE_NAME("acpi_video")
@@ -141,11 +143,11 @@ struct acpi_video_device_cap {
u8 _ADR:1; /*Return the unique ID */
u8 _BCL:1; /*Query list of brightness control levels supported */
u8 _BCM:1; /*Set the brightness level */
+ u8 _BQC:1; /* Get current brightness level */
u8 _DDC:1; /*Return the EDID for this device */
u8 _DCS:1; /*Return status of output device */
u8 _DGS:1; /*Query graphics state */
u8 _DSS:1; /*Device state set */
- u8 _reserved:1;
};
struct acpi_video_device_brightness {
@@ -162,6 +164,8 @@ struct acpi_video_device {
struct acpi_video_bus *video;
struct acpi_device *dev;
struct acpi_video_device_brightness *brightness;
+ struct backlight_device *backlight;
+ struct backlight_properties *data;
};
/* bus */
@@ -256,11 +260,35 @@ static void acpi_video_device_bind(struc
struct acpi_video_device *device);
static int acpi_video_device_enumerate(struct acpi_video_bus *video);
static int acpi_video_switch_output(struct acpi_video_bus *video, int event);
+static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
+ int level);
+static int acpi_video_device_lcd_get_level_current(
+ struct acpi_video_device *device,
+ unsigned long *level);
static int acpi_video_get_next_level(struct acpi_video_device *device,
u32 level_current, u32 event);
static void acpi_video_switch_brightness(struct acpi_video_device *device,
int event);
+/*backlight device sysfs support*/
+static int acpi_video_get_brightness(struct backlight_device *bd)
+{
+ unsigned long cur_level;
+ struct acpi_video_device *vd =
+ (struct acpi_video_device *)class_get_devdata(&bd->class_dev);
+ acpi_video_device_lcd_get_level_current(vd, &cur_level);
+ return (int) cur_level;
+}
+
+static int acpi_video_set_brightness(struct backlight_device *bd)
+{
+ int request_level = bd->props->brightness;
+ struct acpi_video_device *vd =
+ (struct acpi_video_device *)class_get_devdata(&bd->class_dev);
+ acpi_video_device_lcd_set_level(vd, request_level);
+ return 0;
+}
+
/* --------------------------------------------------------------------------
Video Management
-------------------------------------------------------------------------- */
@@ -498,6 +526,7 @@ static void acpi_video_device_find_cap(s
acpi_integer status;
acpi_handle h_dummy1;
int i;
+ u32 max_level = 0;
union acpi_object *obj = NULL;
struct acpi_video_device_brightness *br = NULL;
@@ -513,6 +542,8 @@ static void acpi_video_device_find_cap(s
if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCM", &h_dummy1))) {
device->cap._BCM = 1;
}
+ if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle,"_BQC",&h_dummy1)))
+ device->cap._BQC = 1;
if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_DDC", &h_dummy1))) {
device->cap._DDC = 1;
}
@@ -550,6 +581,8 @@ static void acpi_video_device_find_cap(s
continue;
}
br->levels[count] = (u32) o->integer.value;
+ if (br->levels[count] > max_level)
+ max_level = br->levels[count];
count++;
}
out:
@@ -568,6 +601,37 @@ static void acpi_video_device_find_cap(s
kfree(obj);
+ if (device->cap._BCL && device->cap._BCM && device->cap._BQC){
+ unsigned long tmp;
+ static int count = 0;
+ char *name;
+ struct backlight_properties *acpi_video_data;
+
+ name = kzalloc(MAX_NAME_LEN, GFP_KERNEL);
+ if (!name)
+ return;
+
+ acpi_video_data = kzalloc(
+ sizeof(struct backlight_properties),
+ GFP_KERNEL);
+ if (!acpi_video_data){
+ kfree(name);
+ return;
+ }
+ acpi_video_data->owner = THIS_MODULE;
+ acpi_video_data->get_brightness =
+ acpi_video_get_brightness;
+ acpi_video_data->update_status =
+ acpi_video_set_brightness;
+ sprintf(name, "acpi_video%d", count++);
+ device->data = acpi_video_data;
+ acpi_video_data->max_brightness = max_level;
+ acpi_video_device_lcd_get_level_current(device, &tmp);
+ acpi_video_data->brightness = (int)tmp;
+ device->backlight = backlight_device_register(name,
+ NULL, device, acpi_video_data);
+ kfree(name);
+ }
return;
}
@@ -1564,7 +1628,10 @@ static int acpi_video_bus_put_one_device
status = acpi_remove_notify_handler(device->dev->handle,
ACPI_DEVICE_NOTIFY,
acpi_video_device_notify);
-
+ if (device->backlight){
+ backlight_device_unregister(device->backlight);
+ kfree(device->data);
+ }
return 0;
}
> Adds backlight sysfs support for acpi video driver.
>
> signed-off-by: Luming Yu <[email protected]>
Ug. Watch out. Right now the backlight code requires framebuffer to be
enabled. I seen a patch some time ago by Tony the allowed backlight
support which I need to integrate.
P.S
It would be really nice if the acpi backlight could be exposed to
the VESA framebuffer or any other driver whos backlight is not
implemented.