Re: [PATCH v7 4/5] media: platform: mediatek: isp: add mediatek ISP3.0 camsv

[CK Hu (胡俊光)]

Hi, Julien:

On Thu, 2024-11-21 at 09:53 +0100, Julien Stephan wrote:
> External email : Please do not click links or open attachments until you have verified the sender or the content.
> 
> 
> From: Phi-bang Nguyen <pnguyen@xxxxxxxxxxxx>
> 
> This driver provides a path to bypass the SoC ISP so that image data
> coming from the SENINF can go directly into memory without any image
> processing. This allows the use of an external ISP.
> 
> Signed-off-by: Phi-bang Nguyen <pnguyen@xxxxxxxxxxxx>
> Signed-off-by: Florian Sylvestre <fsylvestre@xxxxxxxxxxxx>
> [Paul Elder fix irq locking]
> Signed-off-by: Paul Elder <paul.elder@xxxxxxxxxxxxxxxx>
> Co-developed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Co-developed-by: Julien Stephan <jstephan@xxxxxxxxxxxx>
> Signed-off-by: Julien Stephan <jstephan@xxxxxxxxxxxx>
> ---

[snip]

> +static void mtk_camsv30_update_buffers_add(struct mtk_cam_dev *cam_dev,
> +                                          struct mtk_cam_dev_buffer *buf)
> +{
> +       mtk_camsv30_img0_write(cam_dev, CAMSV_IMGO_SV_BASE_ADDR, buf->daddr);
> +}
> +

[snip]

> +static void mtk_camsv30_fbc_inc(struct mtk_cam_dev *cam_dev)
> +{
> +       unsigned int fbc_val;
> +
> +       if (pm_runtime_resume_and_get(cam_dev->dev) < 0) {

I think this pm_runtime_resume_and_get() is not necessary.
mtk_camsv30_fbc_inc() is called only in mtk_cam_vb2_buf_queue().
But when buf_list is empty, mtk_camsv30_update_buffers_add() is called before this function.
But mtk_camsv30_update_buffers_add() does not call pm_runtime_resume_and_get() and it works normally.
So this function is not necessary to call pm_runtime_resume_and_get().

In other register setting function, please also check this pm function is necessary or not.

Regards,
CK

> +               dev_err(cam_dev->dev, "failed to get pm_runtime\n");
> +               return;
> +       }
> +
> +       fbc_val = mtk_camsv30_read(cam_dev, CAMSV_IMGO_FBC);
> +       fbc_val |= CAMSV_IMGO_FBC_RCNT_INC;
> +       mtk_camsv30_write(cam_dev, CAMSV_IMGO_FBC, fbc_val);
> +       fbc_val &= ~CAMSV_IMGO_FBC_RCNT_INC;
> +       mtk_camsv30_write(cam_dev, CAMSV_IMGO_FBC, fbc_val);
> +
> +       pm_runtime_put_autosuspend(cam_dev->dev);
> +}
> +

>