Re: [PATCH 1/2] media: s5p-mfc: check for firmware allocation before requesting firmware

From: Shuah Khan
Date: Thu Nov 02 2017 - 20:24:03 EST


On 11/02/2017 02:12 AM, Andrzej Hajda wrote:
> Hi Shuah,
>
> On 06.10.2017 23:30, Shuah Khan wrote:
>> Check if firmware is allocated before requesting firmware instead of
>> requesting firmware only to release it if firmware is not allocated.
>>
>> Signed-off-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx>
>> ---
>> drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c | 10 +++++-----
>> 1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c b/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
>> index 69ef9c2..f064a0d1 100644
>> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
>> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c
>> @@ -55,6 +55,11 @@ int s5p_mfc_load_firmware(struct s5p_mfc_dev *dev)
>> * into kernel. */
>> mfc_debug_enter();
>>
>> + if (!dev->fw_buf.virt) {
>> + mfc_err("MFC firmware is not allocated\n");
>> + return -EINVAL;
>> + }
>> +
>> for (i = MFC_FW_MAX_VERSIONS - 1; i >= 0; i--) {
>> if (!dev->variant->fw_name[i])
>> continue;
>> @@ -75,11 +80,6 @@ int s5p_mfc_load_firmware(struct s5p_mfc_dev *dev)
>> release_firmware(fw_blob);
>> return -ENOMEM;
>> }
>> - if (!dev->fw_buf.virt) {
>> - mfc_err("MFC firmware is not allocated\n");
>> - release_firmware(fw_blob);
>> - return -EINVAL;
>> - }
>
> Is there any scenario in which dev->fw_buf.virt is null and
> s5p_mfc_load_firmware is called?
> I suspect this check is not necessary at all.
>

I don't believe so. Allocation is done in s5p_mfc_configure_dma_memory()
code path and if that fails it bails out of _probe. I can remove the check
all together.

thanks,
-- Shuah