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path: root/drivers/acpi/acpi_video.c
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Diffstat (limited to 'drivers/acpi/acpi_video.c')
-rw-r--r--drivers/acpi/acpi_video.c49
1 files changed, 27 insertions, 22 deletions
diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 8274a17872ed..a972831dbd66 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -610,16 +610,28 @@ acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
return 0;
}
+/**
+ * acpi_video_device_EDID() - Get EDID from ACPI _DDC
+ * @device: video output device (LCD, CRT, ..)
+ * @edid: address for returned EDID pointer
+ * @length: _DDC length to request (must be a multiple of 128)
+ *
+ * Get EDID from ACPI _DDC. On success, a pointer to the EDID data is written
+ * to the @edid address, and the length of the EDID is returned. The caller is
+ * responsible for freeing the edid pointer.
+ *
+ * Return the length of EDID (positive value) on success or error (negative
+ * value).
+ */
static int
-acpi_video_device_EDID(struct acpi_video_device *device,
- union acpi_object **edid, int length)
+acpi_video_device_EDID(struct acpi_video_device *device, void **edid, int length)
{
- int status;
+ acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
union acpi_object arg0 = { ACPI_TYPE_INTEGER };
struct acpi_object_list args = { 1, &arg0 };
-
+ int ret;
*edid = NULL;
@@ -636,16 +648,17 @@ acpi_video_device_EDID(struct acpi_video_device *device,
obj = buffer.pointer;
- if (obj && obj->type == ACPI_TYPE_BUFFER)
- *edid = obj;
- else {
+ if (obj && obj->type == ACPI_TYPE_BUFFER) {
+ *edid = kmemdup(obj->buffer.pointer, obj->buffer.length, GFP_KERNEL);
+ ret = *edid ? obj->buffer.length : -ENOMEM;
+ } else {
acpi_handle_debug(device->dev->handle,
"Invalid _DDC data for length %d\n", length);
- status = -EFAULT;
- kfree(obj);
+ ret = -EFAULT;
}
- return status;
+ kfree(obj);
+ return ret;
}
/* bus */
@@ -1435,9 +1448,7 @@ int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
{
struct acpi_video_bus *video;
struct acpi_video_device *video_device;
- union acpi_object *buffer = NULL;
- acpi_status status;
- int i, length;
+ int i, length, ret;
if (!device || !acpi_driver_data(device))
return -EINVAL;
@@ -1477,16 +1488,10 @@ int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
}
for (length = 512; length > 0; length -= 128) {
- status = acpi_video_device_EDID(video_device, &buffer,
- length);
- if (ACPI_SUCCESS(status))
- break;
+ ret = acpi_video_device_EDID(video_device, edid, length);
+ if (ret > 0)
+ return ret;
}
- if (!length)
- continue;
-
- *edid = buffer->buffer.pointer;
- return length;
}
return -ENODEV;