Re: [PATCH v3 1/5] ACPI: video: Handle fetching EDID that is longer than 256 bytes
On Fri, Feb 2, 2024 at 5:09 PM Mario Limonciello wrote: > > On 2/2/2024 10:07, Rafael J. Wysocki wrote: > > On Thu, Feb 1, 2024 at 11:11 PM Mario Limonciello > > wrote: > >> > >> The ACPI specification allows for an EDID to be up to 512 bytes but > >> the _DDC EDID fetching code will only try up to 256 bytes. > >> > >> Modify the code to instead start at 512 bytes and work it's way > >> down instead. > >> > >> As _DDC is now called up to 4 times on a machine debugging messages > >> are noisier than necessary. Decrease from info to debug. > >> > >> Link: > >> https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/Apx_B_Video_Extensions/output-device-specific-methods.html#ddc-return-the-edid-for-this-device > >> Signed-off-by: Mario Limonciello > > > > Acked-by: Rafael J. Wysocki > > > > or I can apply it if that's preferred. > > Thanks! > > I think go ahead and apply this one to your -next tree. Applied now. Barring any issues with it, It will get into linux-next in a couple of days. Thanks!
Re: [PATCH v3 1/5] ACPI: video: Handle fetching EDID that is longer than 256 bytes
On 2/2/2024 10:07, Rafael J. Wysocki wrote:
On Thu, Feb 1, 2024 at 11:11 PM Mario Limonciello
wrote:
The ACPI specification allows for an EDID to be up to 512 bytes but
the _DDC EDID fetching code will only try up to 256 bytes.
Modify the code to instead start at 512 bytes and work it's way
down instead.
As _DDC is now called up to 4 times on a machine debugging messages
are noisier than necessary. Decrease from info to debug.
Link:
https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/Apx_B_Video_Extensions/output-device-specific-methods.html#ddc-return-the-edid-for-this-device
Signed-off-by: Mario Limonciello
Acked-by: Rafael J. Wysocki
or I can apply it if that's preferred.
Thanks!
I think go ahead and apply this one to your -next tree.
The rest might take a few weeks to get right and no need to block on this.
Thanks!
---
v1->v2:
* Use for loop for acpi_video_get_edid()
* Use one of Rafael's suggestions for acpi_video_device_EDID()
* Decrease message level too
---
drivers/acpi/acpi_video.c | 25 +
1 file changed, 9 insertions(+), 16 deletions(-)
diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 4afdda9db019..3bfd013e09d2 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -625,12 +625,9 @@ acpi_video_device_EDID(struct acpi_video_device *device,
if (!device)
return -ENODEV;
- if (length == 128)
- arg0.integer.value = 1;
- else if (length == 256)
- arg0.integer.value = 2;
- else
+ if (!length || (length % 128))
return -EINVAL;
+ arg0.integer.value = length / 128;
status = acpi_evaluate_object(device->dev->handle, "_DDC", &args,
&buffer);
if (ACPI_FAILURE(status))
@@ -641,7 +638,8 @@ acpi_video_device_EDID(struct acpi_video_device *device,
if (obj && obj->type == ACPI_TYPE_BUFFER)
*edid = obj;
else {
- acpi_handle_info(device->dev->handle, "Invalid _DDC data\n");
+ acpi_handle_debug(device->dev->handle,
+"Invalid _DDC data for length %ld\n", length);
status = -EFAULT;
kfree(obj);
}
@@ -1447,7 +1445,6 @@ int acpi_video_get_edid(struct acpi_device *device, int
type, int device_id,
for (i = 0; i < video->attached_count; i++) {
video_device = video->attached_array[i].bind_info;
- length = 256;
if (!video_device)
continue;
@@ -1478,18 +1475,14 @@ int acpi_video_get_edid(struct acpi_device *device, int
type, int device_id,
continue;
}
- status = acpi_video_device_EDID(video_device, &buffer, length);
-
- if (ACPI_FAILURE(status) || !buffer ||
- buffer->type != ACPI_TYPE_BUFFER) {
- length = 128;
+ for (length = 512; length > 0; length -= 128) {
status = acpi_video_device_EDID(video_device, &buffer,
length);
- if (ACPI_FAILURE(status) || !buffer ||
- buffer->type != ACPI_TYPE_BUFFER) {
- continue;
- }
+ if (ACPI_SUCCESS(status))
+ break;
}
+ if (!length)
+ continue;
*edid = buffer->buffer.pointer;
return length;
--
2.34.1
Re: [PATCH v3 1/5] ACPI: video: Handle fetching EDID that is longer than 256 bytes
On Thu, Feb 1, 2024 at 11:11 PM Mario Limonciello
wrote:
>
> The ACPI specification allows for an EDID to be up to 512 bytes but
> the _DDC EDID fetching code will only try up to 256 bytes.
>
> Modify the code to instead start at 512 bytes and work it's way
> down instead.
>
> As _DDC is now called up to 4 times on a machine debugging messages
> are noisier than necessary. Decrease from info to debug.
>
> Link:
> https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/Apx_B_Video_Extensions/output-device-specific-methods.html#ddc-return-the-edid-for-this-device
> Signed-off-by: Mario Limonciello
Acked-by: Rafael J. Wysocki
or I can apply it if that's preferred.
Thanks!
> ---
> v1->v2:
> * Use for loop for acpi_video_get_edid()
> * Use one of Rafael's suggestions for acpi_video_device_EDID()
> * Decrease message level too
> ---
> drivers/acpi/acpi_video.c | 25 +
> 1 file changed, 9 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
> index 4afdda9db019..3bfd013e09d2 100644
> --- a/drivers/acpi/acpi_video.c
> +++ b/drivers/acpi/acpi_video.c
> @@ -625,12 +625,9 @@ acpi_video_device_EDID(struct acpi_video_device *device,
>
> if (!device)
> return -ENODEV;
> - if (length == 128)
> - arg0.integer.value = 1;
> - else if (length == 256)
> - arg0.integer.value = 2;
> - else
> + if (!length || (length % 128))
> return -EINVAL;
> + arg0.integer.value = length / 128;
>
> status = acpi_evaluate_object(device->dev->handle, "_DDC", &args,
> &buffer);
> if (ACPI_FAILURE(status))
> @@ -641,7 +638,8 @@ acpi_video_device_EDID(struct acpi_video_device *device,
> if (obj && obj->type == ACPI_TYPE_BUFFER)
> *edid = obj;
> else {
> - acpi_handle_info(device->dev->handle, "Invalid _DDC data\n");
> + acpi_handle_debug(device->dev->handle,
> +"Invalid _DDC data for length %ld\n",
> length);
> status = -EFAULT;
> kfree(obj);
> }
> @@ -1447,7 +1445,6 @@ int acpi_video_get_edid(struct acpi_device *device, int
> type, int device_id,
>
> for (i = 0; i < video->attached_count; i++) {
> video_device = video->attached_array[i].bind_info;
> - length = 256;
>
> if (!video_device)
> continue;
> @@ -1478,18 +1475,14 @@ int acpi_video_get_edid(struct acpi_device *device,
> int type, int device_id,
> continue;
> }
>
> - status = acpi_video_device_EDID(video_device, &buffer,
> length);
> -
> - if (ACPI_FAILURE(status) || !buffer ||
> - buffer->type != ACPI_TYPE_BUFFER) {
> - length = 128;
> + for (length = 512; length > 0; length -= 128) {
> status = acpi_video_device_EDID(video_device, &buffer,
> length);
> - if (ACPI_FAILURE(status) || !buffer ||
> - buffer->type != ACPI_TYPE_BUFFER) {
> - continue;
> - }
> + if (ACPI_SUCCESS(status))
> + break;
> }
> + if (!length)
> + continue;
>
> *edid = buffer->buffer.pointer;
> return length;
> --
> 2.34.1
>
[PATCH v3 1/5] ACPI: video: Handle fetching EDID that is longer than 256 bytes
The ACPI specification allows for an EDID to be up to 512 bytes but
the _DDC EDID fetching code will only try up to 256 bytes.
Modify the code to instead start at 512 bytes and work it's way
down instead.
As _DDC is now called up to 4 times on a machine debugging messages
are noisier than necessary. Decrease from info to debug.
Link:
https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/Apx_B_Video_Extensions/output-device-specific-methods.html#ddc-return-the-edid-for-this-device
Signed-off-by: Mario Limonciello
---
v1->v2:
* Use for loop for acpi_video_get_edid()
* Use one of Rafael's suggestions for acpi_video_device_EDID()
* Decrease message level too
---
drivers/acpi/acpi_video.c | 25 +
1 file changed, 9 insertions(+), 16 deletions(-)
diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 4afdda9db019..3bfd013e09d2 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -625,12 +625,9 @@ acpi_video_device_EDID(struct acpi_video_device *device,
if (!device)
return -ENODEV;
- if (length == 128)
- arg0.integer.value = 1;
- else if (length == 256)
- arg0.integer.value = 2;
- else
+ if (!length || (length % 128))
return -EINVAL;
+ arg0.integer.value = length / 128;
status = acpi_evaluate_object(device->dev->handle, "_DDC", &args,
&buffer);
if (ACPI_FAILURE(status))
@@ -641,7 +638,8 @@ acpi_video_device_EDID(struct acpi_video_device *device,
if (obj && obj->type == ACPI_TYPE_BUFFER)
*edid = obj;
else {
- acpi_handle_info(device->dev->handle, "Invalid _DDC data\n");
+ acpi_handle_debug(device->dev->handle,
+"Invalid _DDC data for length %ld\n", length);
status = -EFAULT;
kfree(obj);
}
@@ -1447,7 +1445,6 @@ int acpi_video_get_edid(struct acpi_device *device, int
type, int device_id,
for (i = 0; i < video->attached_count; i++) {
video_device = video->attached_array[i].bind_info;
- length = 256;
if (!video_device)
continue;
@@ -1478,18 +1475,14 @@ int acpi_video_get_edid(struct acpi_device *device, int
type, int device_id,
continue;
}
- status = acpi_video_device_EDID(video_device, &buffer, length);
-
- if (ACPI_FAILURE(status) || !buffer ||
- buffer->type != ACPI_TYPE_BUFFER) {
- length = 128;
+ for (length = 512; length > 0; length -= 128) {
status = acpi_video_device_EDID(video_device, &buffer,
length);
- if (ACPI_FAILURE(status) || !buffer ||
- buffer->type != ACPI_TYPE_BUFFER) {
- continue;
- }
+ if (ACPI_SUCCESS(status))
+ break;
}
+ if (!length)
+ continue;
*edid = buffer->buffer.pointer;
return length;
--
2.34.1
