[PATCH] media: qcom: camss: Use a macro to specify the initial buffer count

[PATCH] media: qcom: camss: Use a macro to specify the initial buffer count

[Hangxiang Ma]

Replace the hardcoded buffer count value with a macro to enable
operating on these buffers elsewhere in the CAMSS driver based on this
count. Some of the hardware architectures require deferring the AUP and
REG update until after the CSID configuration and this macro is expected
to be useful in such scenarios.

Signed-off-by: Hangxiang Ma <hangxiang.ma@oss.qualcomm.com>
---
This change use a global macro to specify the initial buffer count. It
meets the requirement that some hardware architectures need to defer the
AUP and REG update to CSID configuration stage.
---
 drivers/media/platform/qcom/camss/camss-vfe.c | 2 +-
 drivers/media/platform/qcom/camss/camss.h     | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
index 09b29ba383f1..2753c2bb6c04 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe.c
@@ -541,7 +541,7 @@ int vfe_enable_output_v2(struct vfe_line *line)
 
 	ops->vfe_wm_start(vfe, output->wm_idx[0], line);
 
-	for (i = 0; i < 2; i++) {
+	for (i = 0; i < CAMSS_INIT_BUF_COUNT; i++) {
 		output->buf[i] = vfe_buf_get_pending(output);
 		if (!output->buf[i])
 			break;
diff --git a/drivers/media/platform/qcom/camss/camss.h b/drivers/media/platform/qcom/camss/camss.h
index a70fbc78ccc3..901f84efaf7d 100644
--- a/drivers/media/platform/qcom/camss/camss.h
+++ b/drivers/media/platform/qcom/camss/camss.h
@@ -41,6 +41,7 @@
 	(to_camss_index(ptr_module, index)->dev)
 
 #define CAMSS_RES_MAX 17
+#define CAMSS_INIT_BUF_COUNT 2
 
 struct camss_subdev_resources {
 	char *regulators[CAMSS_RES_MAX];

---
base-commit: 59a69ef338920ca6a5bca3ec0e13ce32809cea23
change-id: 20251012-use-marco-to-denote-image-buffer-number-cbec071b8436

Best regards,
-- 
Hangxiang Ma <hangxiang.ma@oss.qualcomm.com>

Re: [PATCH] media: qcom: camss: Use a macro to specify the initial buffer count

[Bryan O'Donoghue]

On 15/10/2025 03:42, Hangxiang Ma wrote:
> Replace the hardcoded buffer count value with a macro to enable
> operating on these buffers elsewhere in the CAMSS driver based on this
> count. Some of the hardware architectures require deferring the AUP and
> REG update until after the CSID configuration and this macro is expected
> to be useful in such scenarios.
> 
> Signed-off-by: Hangxiang Ma <hangxiang.ma@oss.qualcomm.com>
> ---
> This change use a global macro to specify the initial buffer count. It
> meets the requirement that some hardware architectures need to defer the
> AUP and REG update to CSID configuration stage.
> ---
>   drivers/media/platform/qcom/camss/camss-vfe.c | 2 +-
>   drivers/media/platform/qcom/camss/camss.h     | 1 +
>   2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
> index 09b29ba383f1..2753c2bb6c04 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe.c
> @@ -541,7 +541,7 @@ int vfe_enable_output_v2(struct vfe_line *line)
>   
>   	ops->vfe_wm_start(vfe, output->wm_idx[0], line);
>   
> -	for (i = 0; i < 2; i++) {
> +	for (i = 0; i < CAMSS_INIT_BUF_COUNT; i++) {
>   		output->buf[i] = vfe_buf_get_pending(output);
>   		if (!output->buf[i])
>   			break;
> diff --git a/drivers/media/platform/qcom/camss/camss.h b/drivers/media/platform/qcom/camss/camss.h
> index a70fbc78ccc3..901f84efaf7d 100644
> --- a/drivers/media/platform/qcom/camss/camss.h
> +++ b/drivers/media/platform/qcom/camss/camss.h
> @@ -41,6 +41,7 @@
>   	(to_camss_index(ptr_module, index)->dev)
>   
>   #define CAMSS_RES_MAX 17
> +#define CAMSS_INIT_BUF_COUNT 2
>   
>   struct camss_subdev_resources {
>   	char *regulators[CAMSS_RES_MAX];
> 
> ---
> base-commit: 59a69ef338920ca6a5bca3ec0e13ce32809cea23
> change-id: 20251012-use-marco-to-denote-image-buffer-number-cbec071b8436
> 
> Best regards,
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

Re: [PATCH] media: qcom: camss: Use a macro to specify the initial buffer count

[Vladimir Zapolskiy]

On 10/15/25 05:42, Hangxiang Ma wrote:
> Replace the hardcoded buffer count value with a macro to enable
> operating on these buffers elsewhere in the CAMSS driver based on this
> count. Some of the hardware architectures require deferring the AUP and
> REG update until after the CSID configuration and this macro is expected
> to be useful in such scenarios.
> 
> Signed-off-by: Hangxiang Ma <hangxiang.ma@oss.qualcomm.com>
> ---
> This change use a global macro to specify the initial buffer count. It
> meets the requirement that some hardware architectures need to defer the
> AUP and REG update to CSID configuration stage.

Both the commit message and the explanation above brings no clarity on
the necessity of this change at all.

This is a dangling useless commit, if you'd like to connect it to
something meaningful, please include it into a series.

> ---
>   drivers/media/platform/qcom/camss/camss-vfe.c | 2 +-
>   drivers/media/platform/qcom/camss/camss.h     | 1 +
>   2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
> index 09b29ba383f1..2753c2bb6c04 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe.c
> @@ -541,7 +541,7 @@ int vfe_enable_output_v2(struct vfe_line *line)
>   
>   	ops->vfe_wm_start(vfe, output->wm_idx[0], line);
>   
> -	for (i = 0; i < 2; i++) {
> +	for (i = 0; i < CAMSS_INIT_BUF_COUNT; i++) {
>   		output->buf[i] = vfe_buf_get_pending(output);
>   		if (!output->buf[i])
>   			break;
> diff --git a/drivers/media/platform/qcom/camss/camss.h b/drivers/media/platform/qcom/camss/camss.h
> index a70fbc78ccc3..901f84efaf7d 100644
> --- a/drivers/media/platform/qcom/camss/camss.h
> +++ b/drivers/media/platform/qcom/camss/camss.h
> @@ -41,6 +41,7 @@
>   	(to_camss_index(ptr_module, index)->dev)
>   
>   #define CAMSS_RES_MAX 17
> +#define CAMSS_INIT_BUF_COUNT 2
>   
>   struct camss_subdev_resources {
>   	char *regulators[CAMSS_RES_MAX];
> 

-- 
Best wishes,
Vladimir

Re: [PATCH] media: qcom: camss: Use a macro to specify the initial buffer count

[Bryan O'Donoghue]

On 15/10/2025 20:22, Vladimir Zapolskiy wrote:
> On 10/15/25 05:42, Hangxiang Ma wrote:
>> Replace the hardcoded buffer count value with a macro to enable
>> operating on these buffers elsewhere in the CAMSS driver based on this
>> count. Some of the hardware architectures require deferring the AUP and
>> REG update until after the CSID configuration and this macro is expected
>> to be useful in such scenarios.
>>
>> Signed-off-by: Hangxiang Ma <hangxiang.ma@oss.qualcomm.com>
>> ---
>> This change use a global macro to specify the initial buffer count. It
>> meets the requirement that some hardware architectures need to defer the
>> AUP and REG update to CSID configuration stage.
> 
> Both the commit message and the explanation above brings no clarity on
> the necessity of this change at all.

I don't agree. Removing a hard-coded value for a define is an obviously 
correct change.

> This is a dangling useless commit, if you'd like to connect it to
> something meaningful, please include it into a series.

No. It is fine as is.

---
bod