Re: [PATCH 11/17] drm: renesas: rz-du: mipi_dsi: Add OF data support

["Lad, Prabhakar" <prabhakar.csengg@gmail.com>]

Hi Biju,

Thank you for the review.

On Mon, Mar 31, 2025 at 1:38 PM Biju Das <biju.das.jz@bp.renesas.com> wrote:
>
> Hi Prabhakar,
>
> Thanks for the patch.
>
> > -----Original Message-----
> > From: Prabhakar <prabhakar.csengg@gmail.com>
> > Sent: 30 March 2025 22:07
> > Subject: [PATCH 11/17] drm: renesas: rz-du: mipi_dsi: Add OF data support
> >
> > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> >
> > In preparation for adding support for the Renesas RZ/V2H(P) SoC, this patch introduces a mechanism to
> > pass SoC-specific information via OF data in the DSI driver. This enables the driver to adapt
> > dynamically to various SoC-specific requirements without hardcoding configurations.
> >
> > The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to the one on the RZ/G2L SoC. While
> > the LINK registers are shared between the two SoCs, the D-PHY registers differ. Also the VCLK range
> > differs on both these SoCs. To accommodate these differences `struct rzg2l_mipi_dsi_hw_info` is
> > introduced and as now passed as OF data.
> >
> > These changes lay the groundwork for the upcoming RZ/V2H(P) SoC support by allowing SoC-specific data
> > to be passed through OF.
> >
<snip>
> > +
> >       ret = drm_of_get_data_lanes_count_ep(dsi->dev->of_node, 1, 0, 1, 4);
> >       if (ret < 0)
> >               return dev_err_probe(dsi->dev, ret,
> > @@ -729,10 +750,12 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
> >       if (IS_ERR(dsi->vclk))
> >               return PTR_ERR(dsi->vclk);
> >
> > -     dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
> > -     if (IS_ERR(dsi->rstc))
> > -             return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
> > -                                  "failed to get rst\n");
> > +     if (dsi->info->has_dphy_rstc) {
> > +             dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
>
> Maybe use devm_reset_control_get_optional_exclusive by dropping has_dphy_rstc.
>
As the dtbs_check doesn't enforce this,  `has_dphy_rstc` flag was
added. Recently the same was done for the CRU [0] based on the recent
comment received.

[0] https://patchwork.kernel.org/project/linux-renesas-soc/patch/20250328173032.423322-10-tommaso.merciai.xr@bp.renesas.com/

Cheers,
Prabhakar