Re: [PATCH v5,8/8] media: mediatek: vcodec: Add dbgfs help function

[Yunfei Dong (董云飞)]

Hi Hans,

On Tue, 2023-05-30 at 12:33 +0200, Hans Verkuil wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  On 5/30/23 12:06, AngeloGioacchino Del Regno wrote:
> > Il 25/05/23 04:12, Yunfei Dong ha scritto:
> >> Getting dbgfs help information with command "echo -help > vdec".
> >>
> >> Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx>
> >> ---
> >>   .../mediatek/vcodec/mtk_vcodec_dbgfs.c        | 24
> ++++++++++++++++++-
> >>   1 file changed, 23 insertions(+), 1 deletion(-)
> >>
> >> diff --git
> a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dbgfs.c
> b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dbgfs.c
> >> index 237d0dc8a1fc..2372fc449b45 100644
> >> --- a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dbgfs.c
> >> +++ b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dbgfs.c
> >> @@ -52,6 +52,23 @@ static void
> mtk_vdec_dbgfs_get_format_type(struct mtk_vcodec_ctx *ctx, char *buf
> >>   *used += curr_len;
> >>   }
> >>   
> >> +static void mtk_vdec_dbgfs_get_help(char *buf, int *used, int
> total)
> >> +{
> >> +int curr_len;
> >> +
> >> +curr_len = snprintf(buf + *used, total - *used,
> >> +    "help: (1: echo -'info' > vdec 2: cat vdec)\n");
> >> +*used += curr_len;
> >> +
> >> +curr_len = snprintf(buf + *used, total - *used,
> >> +    "\t-picinfo: get resolution\n");
> >> +*used += curr_len;
> >> +
> >> +curr_len = snprintf(buf + *used, total - *used,
> >> +    "\t-format: get output & capture queue format\n");
> >> +*used += curr_len;
> >> +}
> >> +
> >>   static ssize_t mtk_vdec_dbgfs_write(struct file *filp, const
> char __user *ubuf,
> >>       size_t count, loff_t *ppos)
> >>   {
> >> @@ -84,6 +101,11 @@ static ssize_t mtk_vdec_dbgfs_read(struct file
> *filp, char __user *ubuf,
> >>   if (!buf)
> >>   return -ENOMEM;
> >>   
> >> +if (strstr(dbgfs->dbgfs_buf, "-help")) {
> > 
> > I would print the help strings in two conditions:
> > 1. -help
> > 2. (nothing)
> > 
> > ...so that if you don't echo anything to vdec (no params), you get
> the help text.
> > Otherwise, you would have to know that "-help" is a parameter that
> gives you help
> > text in the first place.
> > 
> > As for this commit "as is", it works as intended and it is useful
> to retrieve
> > the help text; you can either send a followup commit that extends
> the help to
> > the corner case that I've explained, or send a v6 adding that to
> this same commit.
> > 
> > I would prefer to see a v6 -- BUT -- since this series was sent a
> long time ago,
> > you will get my R-b and I will leave the final choice to Hans.
> > 
> > Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@xxxxxxxxxxxxx>
> > 
> > 
> 
> I prefer a v6, rebased on top of the media_stage tree.
> 
> Regards,
> 
> Hans

I already have sent patch v6 to review.

Best Regards,
Yunfei Dong