Re: [PATCH v5 2/5] media: iris: scale MMCX power domain on SM8250

[Dmitry Baryshkov]

On Tue, Mar 31, 2026 at 01:33:35PM +0200, Ulf Hansson wrote:
> On Mon, 30 Mar 2026 at 15:06, Dikshita Agarwal
> <dikshita.agarwal@xxxxxxxxxxxxxxxx> wrote:
> >
> >
> >
> > On 3/30/2026 4:45 PM, Dmitry Baryshkov wrote:
> > > On Mon, Mar 30, 2026 at 10:55:02AM +0530, Dikshita Agarwal wrote:
> > >>
> > >>
> > >> On 2/9/2026 7:02 AM, Dmitry Baryshkov wrote:
> > >>> On SM8250 most of the video clocks are powered by the MMCX domain, while
> > >>> the PLL is powered on by the MX domain. Extend the driver to support
> > >>> scaling both power domains, while keeping compatibility with the
> > >>> existing DTs, which define only the MX domain.
> > >>>
> > >>> Fixes: 79865252acb6 ("media: iris: enable video driver probe of SM8250 SoC")
> > >>> Reviewed-by: Dikshita Agarwal <dikshita.agarwal@xxxxxxxxxxxxxxxx>
> > >>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> > >>> ---
> > >>>  drivers/media/platform/qcom/iris/iris_platform_gen1.c | 2 +-
> > >>>  drivers/media/platform/qcom/iris/iris_probe.c         | 7 +++++++
> > >>>  2 files changed, 8 insertions(+), 1 deletion(-)
> > >>>
> > >>> diff --git a/drivers/media/platform/qcom/iris/iris_platform_gen1.c b/drivers/media/platform/qcom/iris/iris_platform_gen1.c
> > >>> index df8e6bf9430e..aa71f7f53ee3 100644
> > >>> --- a/drivers/media/platform/qcom/iris/iris_platform_gen1.c
> > >>> +++ b/drivers/media/platform/qcom/iris/iris_platform_gen1.c
> > >>> @@ -281,7 +281,7 @@ static const struct bw_info sm8250_bw_table_dec[] = {
> > >>>
> > >>>  static const char * const sm8250_pmdomain_table[] = { "venus", "vcodec0" };
> > >>>
> > >>> -static const char * const sm8250_opp_pd_table[] = { "mx" };
> > >>> +static const char * const sm8250_opp_pd_table[] = { "mx", "mmcx" };
> > >>>
> > >>>  static const struct platform_clk_data sm8250_clk_table[] = {
> > >>>     {IRIS_AXI_CLK,  "iface"        },
> > >>> diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
> > >>> index 7b612ad37e4f..74ec81e3d622 100644
> > >>> --- a/drivers/media/platform/qcom/iris/iris_probe.c
> > >>> +++ b/drivers/media/platform/qcom/iris/iris_probe.c
> > >>> @@ -64,6 +64,13 @@ static int iris_init_power_domains(struct iris_core *core)
> > >>>             return ret;
> > >>>
> > >>>     ret =  devm_pm_domain_attach_list(core->dev, &iris_opp_pd_data, &core->opp_pmdomain_tbl);
> > >>> +   /* backwards compatibility for incomplete ABI SM8250 */
> > >>> +   if (ret == -ENODEV &&
> > >>> +       of_device_is_compatible(core->dev->of_node, "qcom,sm8250-venus")) {
> > >>> +           iris_opp_pd_data.num_pd_names--;
> > >>> +           ret = devm_pm_domain_attach_list(core->dev, &iris_opp_pd_data,
> > >>> +                                            &core->opp_pmdomain_tbl);
> > >>> +   }
> > >>>     if (ret < 0)
> > >>>             return ret;
> > >>>
> > >>>
> > >>
> > >> Hitting below compilation error on latest kernel
> > >>
> > >> drivers/media/platform/qcom/iris/iris_probe.c: In function
> > >> ‘iris_init_power_domains’:
> > >> drivers/media/platform/qcom/iris/iris_probe.c:71:46: error: decrement of
> > >> read-only member ‘num_pd_names’
> > >>    71 |                 iris_opp_pd_data.num_pd_names--;
> > >
> > > See commit 7ad7f43e568b ("pmdomain: de-constify fields struct
> > > dev_pm_domain_attach_data")
> 
> The intent was for this patch to be part of v7.0-rc1, but I failed
> with my pull-request to Linus.
> 
> Instead this will be part of v7.1-rc1, assuming everything goes as expected.
> 
> Is it possible to drop/defer these changes until v7.2?

It would be very sad.

> 
> Kind regards
> Uffe

-- 
With best wishes
Dmitry