aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDanny Kukawka <dkukawka@suse.de>2007-07-03 01:33:53 -0400
committerLen Brown <len.brown@intel.com>2007-07-03 01:33:53 -0400
commitf70ac0e9651aa8c07dffe72a44872f92054d42c3 (patch)
treec748973de21f228021e270cb5764029641d4d501
parent23b0f015bf2c050b8b5399430ca64e1b3398cf76 (diff)
ACPI video: Don't export sysfs backlight interface if query _BCL fail
Currently the acpi video module export the backlight interface to sysfs also if acpi_video_device_lcd_query_levels() fails to read _BLC method (e.g. because the method is not available). In this case the userspace don't know which brightness level are supported and can't set a brightness level (echo return with: "write error: Invalid Argument"). This happend e.g. on a ASUS RF1 (correct supported by the asus-laptop module). The video module should not export the backlight interface if query _BLC fail, because you can't set anything from userspace and this make it useless. http://bugzilla.kernel.org/show_bug.cgi?id=8375 Signed-off-by: Danny Kukawka <dkukawka@suse.de> Acked-by: Luming Yu <luming.yu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
-rw-r--r--drivers/acpi/video.c80
1 files changed, 42 insertions, 38 deletions
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 39273dae700..5f014d3764c 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -559,7 +559,6 @@ acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
static void acpi_video_device_find_cap(struct acpi_video_device *device)
{
- acpi_integer status;
acpi_handle h_dummy1;
int i;
u32 max_level = 0;
@@ -593,50 +592,55 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
device->cap._DSS = 1;
}
- status = acpi_video_device_lcd_query_levels(device, &obj);
-
- if (obj && obj->type == ACPI_TYPE_PACKAGE && obj->package.count >= 2) {
- int count = 0;
- union acpi_object *o;
-
- br = kzalloc(sizeof(*br), GFP_KERNEL);
- if (!br) {
- printk(KERN_ERR "can't allocate memory\n");
- } else {
- br->levels = kmalloc(obj->package.count *
- sizeof *(br->levels), GFP_KERNEL);
- if (!br->levels)
- goto out;
-
- for (i = 0; i < obj->package.count; i++) {
- o = (union acpi_object *)&obj->package.
- elements[i];
- if (o->type != ACPI_TYPE_INTEGER) {
- printk(KERN_ERR PREFIX "Invalid data\n");
- continue;
- }
- br->levels[count] = (u32) o->integer.value;
- if (br->levels[count] > max_level)
- max_level = br->levels[count];
- count++;
- }
- out:
- if (count < 2) {
- kfree(br->levels);
- kfree(br);
+ if (ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
+
+ if (obj->package.count >= 2) {
+ int count = 0;
+ union acpi_object *o;
+
+ br = kzalloc(sizeof(*br), GFP_KERNEL);
+ if (!br) {
+ printk(KERN_ERR "can't allocate memory\n");
} else {
- br->count = count;
- device->brightness = br;
- ACPI_DEBUG_PRINT((ACPI_DB_INFO,
- "found %d brightness levels\n",
- count));
+ br->levels = kmalloc(obj->package.count *
+ sizeof *(br->levels), GFP_KERNEL);
+ if (!br->levels)
+ goto out;
+
+ for (i = 0; i < obj->package.count; i++) {
+ o = (union acpi_object *)&obj->package.
+ elements[i];
+ if (o->type != ACPI_TYPE_INTEGER) {
+ printk(KERN_ERR PREFIX "Invalid data\n");
+ continue;
+ }
+ br->levels[count] = (u32) o->integer.value;
+
+ if (br->levels[count] > max_level)
+ max_level = br->levels[count];
+ count++;
+ }
+ out:
+ if (count < 2) {
+ kfree(br->levels);
+ kfree(br);
+ } else {
+ br->count = count;
+ device->brightness = br;
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "found %d brightness levels\n",
+ count));
+ }
}
}
+
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available LCD brightness level\n"));
}
kfree(obj);
- if (device->cap._BCL && device->cap._BCM && device->cap._BQC){
+ if (device->cap._BCL && device->cap._BCM && device->cap._BQC && max_level > 0){
unsigned long tmp;
static int count = 0;
char *name;