Re: [PATCH v2 7/9] phy: qcom-qmp: Utilize UFS reset controller

[Stephen Boyd]

Quoting Evan Green (2019-01-23 14:11:35)
> @@ -1144,6 +1150,8 @@ static const struct qmp_phy_cfg sdm845_ufsphy_cfg = {
>  
>         .is_dual_lane_phy       = true,
>         .no_pcs_sw_reset        = true,
> +
> +       .has_ufsphy_reset       = true,

Is this the same as .no_pcs_sw_reset implying that .has_ufsphy_reset? Or
it's possible to have no resets at all? I'd think there's a reset in the
phy or in the pcs and so we could just have one bit telling us which
type of reset to perform.

>  };
>  
>  static const struct qmp_phy_cfg msm8998_usb3phy_cfg = {
> @@ -1314,6 +1322,9 @@ static int qcom_qmp_phy_com_exit(struct qcom_qmp *qmp)
>                 return 0;
>         }
>  
> +       if (qmp->ufs_reset)
> +               reset_control_assert(qmp->ufs_reset);
> +
>         if (cfg->has_phy_com_ctrl) {
>                 qphy_setbits(serdes, cfg->regs[QPHY_COM_START_CONTROL],
>                              SERDES_START | PCS_START);
> @@ -1351,6 +1362,33 @@ static int qcom_qmp_phy_init(struct phy *phy)
>  
>         dev_vdbg(qmp->dev, "Initializing QMP phy\n");
>  
> +       if (cfg->has_ufsphy_reset) {
> +               /*
> +                * Get UFS reset, which is delayed until now to avoid a
> +                * circular dependency where UFS needs its PHY, but the PHY
> +                * needs this UFS reset.
> +                */
> +               if (!qmp->ufs_reset) {
> +                       qmp->ufs_reset =
> +                               devm_reset_control_get_exclusive(qmp->dev,
> +                                                                "ufsphy");
> +
> +                       if (IS_ERR(qmp->ufs_reset)) {
> +                               dev_err(qmp->dev,
> +                                       "failed to get UFS reset: %d\n",
> +                                       PTR_ERR(qmp->ufs_reset));
> +
> +                               ret = PTR_ERR(qmp->ufs_reset);

Do this ret conversion once and then print it after?

> +                               qmp->ufs_reset = NULL;
> +                               return ret;
> +                       }
> +               }
> +
> +               ret = reset_control_assert(qmp->ufs_reset);
> +               if (ret)
> +                       goto err_lane_rst;
> +       }
> +
>         ret = qcom_qmp_phy_com_init(qphy);
>         if (ret)
>                 return ret;