Re: [PATCH 1/6] media: qcom: camss: Program CSIPHY common control registers

[Loic Poulain]

On Sat, Jul 18, 2026 at 1:13 AM Anusha Arun Nandi
<anusha.nandi@xxxxxxxxxxxxxxxx> wrote:
>
> From: Jigarkumar Zala <jigarkumar.zala@xxxxxxxxxxxxxxxx>
>
> Program the CSIPHY common-control registers during lane enable so
> SA8775P uses the required 3-phase 1.5 Gsps reset-release values for
> both C-PHY and D-PHY. Keep the existing reset-release value for the
> other CAMSS variants.
>
> Co-developed-by: Anusha Arun Nandi <anusha.nandi@xxxxxxxxxxxxxxxx>
> Signed-off-by: Anusha Arun Nandi <anusha.nandi@xxxxxxxxxxxxxxxx>
> Signed-off-by: Jigarkumar Zala <jigarkumar.zala@xxxxxxxxxxxxxxxx>
> ---
>  .../qcom/camss/camss-csiphy-3ph-1-0.c         | 36 ++++++++++++++++---
>  1 file changed, 31 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/qcom/camss/camss-csiphy-3ph-1-0.c b/drivers/media/platform/qcom/camss/camss-csiphy-3ph-1-0.c
> index 25a3554ef201..11b7a236e607 100644
> --- a/drivers/media/platform/qcom/camss/camss-csiphy-3ph-1-0.c
> +++ b/drivers/media/platform/qcom/camss/camss-csiphy-3ph-1-0.c
> @@ -1031,8 +1031,6 @@ static void csiphy_reset(struct csiphy_device *csiphy)
>         writel_relaxed(0x1, csiphy->base +
>                       CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 0));
>         usleep_range(5000, 8000);
> -       writel_relaxed(0x0, csiphy->base +
> -                      CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 0));
>  }
>
>  static irqreturn_t csiphy_isr(int irq, void *dev)
> @@ -1343,9 +1341,37 @@ static void csiphy_lanes_enable(struct csiphy_device *csiphy,
>         writel_relaxed(val, csiphy->base +
>                        CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 6));
>
> -       val = 0x02;
> -       writel_relaxed(val, csiphy->base +
> -                      CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 7));
> +       switch (csiphy->camss->res->version) {
> +       case CAMSS_8300:
> +       case CAMSS_8775P:
> +               if (c->phy_cfg == V4L2_MBUS_CSI2_CPHY) {
> +                       val = 0x5A;
> +                       writel_relaxed(val, csiphy->base +
> +                                      CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 7));
> +                       val = 0xE;
> +                       writel_relaxed(val, csiphy->base +
> +                                      CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 0));
> +               } else {
> +                       val = 0x02;
> +                       writel_relaxed(val, csiphy->base +
> +                                      CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 7));
> +                       writel_relaxed(val, csiphy->base +
> +                                      CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 0));
> +               }
> +               break;
> +       case CAMSS_7280:
> +       case CAMSS_8250:
> +       case CAMSS_8280XP:
> +       case CAMSS_845:
> +       default:
> +               val = 0x02;
> +               writel_relaxed(val, csiphy->base +
> +                              CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 7));
> +               val = 0x0;
> +               writel_relaxed(val, csiphy->base +
> +                              CSIPHY_3PH_CMN_CSI_COMMON_CTRLn(regs->offset, 0));
> +               break;
> +       }

I don't really like this big camss-version switch case with magic,
which also introduces more magic values. Maybe we should have a
different version of csiphy_lanes_enable, based on the phy compatible
or revision.

>
>         val = 0x00;
>         writel_relaxed(val, csiphy->base +
> --
> 2.34.1
>
>