Hi Hans,
On Mon, Jun 10, 2024 at 11:06:30AM +0200, Hans Verkuil wrote:
> On 10/06/2024 11:00, Laurent Pinchart wrote:
> > On Mon, Jun 10, 2024 at 09:14:59AM +0300, Tomi Valkeinen wrote:
> >> On 10/06/2024 04:22, Laurent Pinchart wrote:
> >>> Add a -W/--which argument to media-ctl to select which state to operate
> >>> on. Default to the ACTIVE state to preserve the current behaviour.
> >>>
> >>> Despite the fact that all values set on the TRY state are lost when
> >>> media-ctl terminates, support for the TRY state is useful in order to
> >>> retrieve the default configuration of subdevs, or to try configurations.
> >>
> >> I think this is fine, but I'm curious why you chose such an argument. I
> >> would have thought "-t/--try" (or even just --try) would have been
> >> simpler to implement and to use. I think I would remember "--try"
> >> easily, but "-W TRY", I fear I'll have to check the man page every time...
> >
> > There are a few reasons:
> >
> > - Be closer to the API (media-ctl is a low-level tool)
> > - Support other values later if the kernel API evolves (no plan for
> > that, but who knows ?)
> > - I find it easier to propagate arguments in scripts this way. If a
> > script that wraps media-ctl receives a nothing/--try argument, it's
> > fairly easy to translate that to nothing/-W TRY. If it receives a
> > --foo ACTIVE/TRY argument (on the command line, in an interactive
> > prompt, as part of a string that tells what to do on a pad, ...), then
> > translating that to '-W arg' is easier than to nothing/-W TRY.
> >
> >>> Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> >>> ---
> >>> utils/media-ctl/media-ctl.c | 13 +++++++------
> >>> utils/media-ctl/options.c | 18 +++++++++++++++++-
> >>> utils/media-ctl/options.h | 1 +
> >>> 3 files changed, 25 insertions(+), 7 deletions(-)
> >>>
> >>> diff --git a/utils/media-ctl/media-ctl.c b/utils/media-ctl/media-ctl.c
> >>> index 42b1bd9aaa6e..33df0880fd9b 100644
> >>> --- a/utils/media-ctl/media-ctl.c
> >>> +++ b/utils/media-ctl/media-ctl.c
> >>> @@ -600,7 +600,6 @@ static void media_print_topology_text(struct media_device *media,
> >>>
> >>> int main(int argc, char **argv)
> >>> {
> >>> - const enum v4l2_subdev_format_whence which = V4L2_SUBDEV_FORMAT_ACTIVE;
> >>> struct media_device *media;
> >>> struct media_entity *entity = NULL;
> >>> int ret = -1;
> >>> @@ -667,7 +666,8 @@ int main(int argc, char **argv)
> >>> goto out;
> >>> }
> >>>
> >>> - v4l2_subdev_print_format(pad->entity, pad->index, stream, which);
> >>> + v4l2_subdev_print_format(pad->entity, pad->index, stream,
> >>> + media_opts.which);
> >>> }
> >>>
> >>> if (media_opts.get_dv_pad) {
> >>> @@ -709,9 +709,10 @@ int main(int argc, char **argv)
> >>> media_print_topology_dot(media);
> >>> } else if (media_opts.print) {
> >>> if (entity)
> >>> - media_print_topology_text_entity(media, entity, which);
> >>> + media_print_topology_text_entity(media, entity,
> >>> + media_opts.which);
> >>> else
> >>> - media_print_topology_text(media, which);
> >>> + media_print_topology_text(media, media_opts.which);
> >>> } else if (entity) {
> >>> const char *devname;
> >>>
> >>> @@ -741,7 +742,7 @@ int main(int argc, char **argv)
> >>> }
> >>>
> >>> if (media_opts.routes) {
> >>> - ret = v4l2_subdev_parse_setup_routes(media, which,
> >>> + ret = v4l2_subdev_parse_setup_routes(media, media_opts.which,
> >>> media_opts.routes);
> >>> if (ret) {
> >>> printf("Unable to setup routes: %s (%d)\n",
> >>> @@ -751,7 +752,7 @@ int main(int argc, char **argv)
> >>> }
> >>>
> >>> if (media_opts.formats) {
> >>> - ret = v4l2_subdev_parse_setup_formats(media, which,
> >>> + ret = v4l2_subdev_parse_setup_formats(media, media_opts.which,
> >>> media_opts.formats);
> >>> if (ret) {
> >>> printf("Unable to setup formats: %s (%d)\n",
> >>> diff --git a/utils/media-ctl/options.c b/utils/media-ctl/options.c
> >>> index 3c408a1b9b06..3606525c33da 100644
> >>> --- a/utils/media-ctl/options.c
> >>> +++ b/utils/media-ctl/options.c
> >>> @@ -40,6 +40,7 @@
> >>>
> >>> struct media_options media_opts = {
> >>> .devname = MEDIA_DEVNAME_DEFAULT,
> >>> + .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> >>> };
> >>>
> >>> static void print_version()
> >>> @@ -75,6 +76,7 @@ static void usage(const char *argv0)
> >>> printf("-r, --reset Reset all links to inactive\n");
> >>> printf("-v, --verbose Be verbose\n");
> >>> printf(" --version Show version information\n");
> >>> + printf("-W, --which which Select the subdev state to operate on\n");
> >>> printf("\n");
> >>> printf("Links and formats are defined as\n");
> >>> printf("\tlinks = link { ',' link } ;\n");
> >>> @@ -140,6 +142,8 @@ static void usage(const char *argv0)
> >>> for (i = V4L2_YCBCR_ENC_DEFAULT; i <= V4L2_YCBCR_ENC_SMPTE240M; i++)
> >>> printf("\t %s\n",
> >>> v4l2_subdev_ycbcr_encoding_to_string(i));
> >>> +
> >>> + printf("\twhich Subdev state ('ACTIVE' or 'TRY')\n");
> >>> }
> >>>
> >>> #define OPT_PRINT_DOT 256
> >>> @@ -168,6 +172,7 @@ static struct option opts[] = {
> >>> {"reset", 0, 0, 'r'},
> >>> {"verbose", 0, 0, 'v'},
> >>> {"version", 0, 0, OPT_VERSION},
> >>> + {"which", 1, 0, 'W'},
> >>> { },
> >>> };
> >>>
> >>> @@ -244,7 +249,7 @@ int parse_cmdline(int argc, char **argv)
> >>> }
> >>>
> >>> /* parse options */
> >>> - while ((opt = getopt_long(argc, argv, "d:e:f:hil:prvV:R:",
> >>> + while ((opt = getopt_long(argc, argv, "d:e:f:hil:prvV:R:W:",
> >>> opts, NULL)) != -1) {
> >>> switch (opt) {
> >>> case 'd':
> >>> @@ -294,6 +299,17 @@ int parse_cmdline(int argc, char **argv)
> >>> media_opts.routes = optarg;
> >>> break;
> >>>
> >>> + case 'W':
> >>> + if (!strcmp(optarg, "ACTIVE"))
> >>> + media_opts.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> >>> + else if (!strcmp(optarg, "TRY"))
> >>> + media_opts.which = V4L2_SUBDEV_FORMAT_TRY;
>
> I very much prefer lower case here since it is a pain to type otherwise.
> Alternatively, make this a case-insensitive string compare, that's fine as well.
I've tried to stick to the kernel API, the same way we use upper-case
media bus codes. If it's generally preferred to use lower-case strings,
or make the comparison case-insensitive, I can do that too. I generally
dislike case-insensitivity though, it can easily lead to confusion.
> >>> + else {
> >>> + printf("Invalid 'which' value '%s'\n", optarg);
> >>> + return 1;
> >>> + }
> >>> + break;
> >>> +
> >>> case OPT_PRINT_DOT:
> >>> media_opts.print_dot = 1;
> >>> break;
> >>> diff --git a/utils/media-ctl/options.h b/utils/media-ctl/options.h
> >>> index 753d09347585..095729b98014 100644
> >>> --- a/utils/media-ctl/options.h
> >>> +++ b/utils/media-ctl/options.h
> >>> @@ -37,6 +37,7 @@ struct media_options
> >>> const char *get_dv_pad;
> >>> const char *dv_pad;
> >>> const char *routes;
> >>> + enum v4l2_subdev_format_whence which;
> >>> };
> >>>
> >>> extern struct media_options media_opts;
--
Regards,
Laurent Pinchart
