[PATCH 058/112] ACPI: register ACPI Video LCD as generic thermal cooling device

Len Brown
2008-02-07T09:36:12Z

From: Zhang Rui <rui.zhang@intel.com>

Register ACPI video device as thermal cooling devices as they may be listed
in _TZD method and the backlight control can be used for throttling.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Thomas Sujith <sujith.thomas@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
---
drivers/acpi/video.c | 78 +++++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 77 insertions(+), 1 deletions(-)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index bd77e81..eab9c42 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -34,6 +34,7 @@
#include <linux/seq_file.h>
#include <linux/input.h>
#include <linux/backlight.h>
+#include <linux/thermal.h>
#include <linux/video_output.h>
#include <asm/uaccess.h>

@@ -179,6 +180,7 @@ struct acpi_video_device {
struct acpi_device *dev;
struct acpi_video_device_brightness *brightness;
struct backlight_device *backlight;
+ struct thermal_cooling_device *cdev;
struct output_device *output_dev;
};

@@ -334,6 +336,54 @@ static struct output_properties acpi_output_properties = {
.set_state = acpi_video_output_set,
.get_status = acpi_video_output_get,
};
+
+
+/* thermal cooling device callbacks */
+static int video_get_max_state(struct thermal_cooling_device *cdev, char *buf)
+{
+ struct acpi_device *device = cdev->devdata;
+ struct acpi_video_device *video = acpi_driver_data(device);
+
+ return sprintf(buf, "%d\n", video->brightness->count - 3);
+}
+
+static int video_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
+{
+ struct acpi_device *device = cdev->devdata;
+ struct acpi_video_device *video = acpi_driver_data(device);
+ unsigned long level;
+ int state;
+
+ acpi_video_device_lcd_get_level_current(video, &level);
+ for (state = 2; state < video->brightness->count; state++)
+ if (level == video->brightness->levels[state])
+ return sprintf(buf, "%d\n",
+ video->brightness->count - state - 1);
+
+ return -EINVAL;
+}
+
+static int
+video_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
+{
+ struct acpi_device *device = cdev->devdata;
+ struct acpi_video_device *video = acpi_driver_data(device);
+ int level;
+
+ if ( state >= video->brightness->count - 2)
+ return -EINVAL;
+
+ state = video->brightness->count - state;
+ level = video->brightness->levels[state -1];
+ return acpi_video_device_lcd_set_level(video, level);
+}
+
+static struct thermal_cooling_device_ops video_cooling_ops = {
+ .get_max_state = video_get_max_state,
+ .get_cur_state = video_get_cur_state,
+ .set_cur_state = video_set_cur_state,
+};
+
/* --------------------------------------------------------------------------
Video Management
-------------------------------------------------------------------------- */
@@ -653,6 +703,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)

if (device->cap._BCL && device->cap._BCM && device->cap._BQC && max_level > 0){
unsigned long tmp;
+ int result;
static int count = 0;
char *name;
name = kzalloc(MAX_NAME_LEN, GFP_KERNEL);
@@ -666,8 +717,25 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
device->backlight->props.max_brightness = max_level;
device->backlight->props.brightness = (int)tmp;
backlight_update_status(device->backlight);
-
kfree(name);
+
+ device->cdev = thermal_cooling_device_register("LCD",
+ device->dev, &video_cooling_ops);
+ if (device->cdev) {
+ printk(KERN_INFO PREFIX
+ "%s is registered as cooling_device%d\n",
+ device->dev->dev.bus_id, device->cdev->id);
+ result = sysfs_create_link(&device->dev->dev.kobj,
+ &device->cdev->device.kobj,
+ "thermal_cooling");
+ if (result)
+ printk(KERN_ERR PREFIX "Create sysfs link\n");
+ result = sysfs_create_link(&device->cdev->device.kobj,
+ &device->dev->dev.kobj,
+ "device");
+ if (result)
+ printk(KERN_ERR PREFIX "Create sysfs link\n");
+ }
}
if (device->cap._DCS && device->cap._DSS){
static int count = 0;
@@ -1729,6 +1797,14 @@ static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
ACPI_DEVICE_NOTIFY,
acpi_video_device_notify);
backlight_device_unregister(device->backlight);
+ if (device->cdev) {
+ sysfs_remove_link(&device->dev->dev.kobj,
+ "thermal_cooling");
+ sysfs_remove_link(&device->cdev->device.kobj,
+ "device");
+ thermal_cooling_device_unregister(device->cdev);
+ device->cdev = NULL;
+ }
video_output_unregister(device->output_dev);

return 0;
--
1.5.4.23.gef5b9