Re: [PATCH 1/2] media: iris: avoid bit depth validation for capture formats

[Vishnu Reddy <busanna.reddy@oss.qualcomm.com>]

On 7/7/2026 2:23 PM, Vikash Garodia wrote:
>
>
> On 7/7/2026 12:05 PM, Vishnu Reddy wrote:
>> When validating a capture format, check_format() compares the requested
>> pixel format against inst->fw_caps[BIT_DEPTH]. However, the bit depth
>> capability is not available at this stage and it contains the default
>> value of BIT_DEPTH_8. The actual bit depth is updated later after the
>> firmware reports stream capabilities through read_input_subcr_params().
>> Because of this, a valid QC10C format request is rejected during the
>
> client request
>

Ack.

>> initial format negotiation. The driver then falls back to the default
>> capture format (NV12) and stores it as capture format.
>>
>
> No new line
>

Ack.

>> Later, when the firmware reports that the stream is 10-bit, the driver
>> sees NV12 as the selected capture format and switches to the default
>> 10-bit format (P010). As a result, the original QC10C format requested
>> by userspace is lost and QC10C decoding cannot work correctly.
>>
>
> No new line.
>

Ack.

>> The bit depth information is not reliable during the initial format
>> setup, so it should not be used to validate capture formats. Remove
>> the bit-depth checks from check_format() and only verify that the
>> requested pixel format is supported. This allows the format requested
>> by userspace is handled correctly.
>>
>> Fixes: 20c3ef4c7cae ("media: qcom: iris: vdec: update find_format to handle
>> 8bit and 10bit formats")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
>> ---
>>   drivers/media/platform/qcom/iris/iris_vdec.c | 10 ----------
>>   1 file changed, 10 deletions(-)
>>
>> diff --git a/drivers/media/platform/qcom/iris/iris_vdec.c
>> b/drivers/media/platform/qcom/iris/iris_vdec.c
>> index 9e228b70420e..7f89e745a4b1 100644
>> --- a/drivers/media/platform/qcom/iris/iris_vdec.c
>> +++ b/drivers/media/platform/qcom/iris/iris_vdec.c
>> @@ -95,16 +95,6 @@ static bool check_format(struct iris_inst *inst, u32
>> pixfmt, u32 type)
>>       if (i == size)
>>           return false;
>>   -    if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
>> -        if (iris_fmt_is_8bit(pixfmt) &&
>> -            inst->fw_caps[BIT_DEPTH].value == BIT_DEPTH_10)
>> -            return false;
>> -
>> -        if (iris_fmt_is_10bit(pixfmt) &&
>> -            inst->fw_caps[BIT_DEPTH].value != BIT_DEPTH_10)
>> -            return false;
>> -    }
>> -
>>       return true;
>>   }
>>  
>