Re: [PATCH v3 03/16] phy: qcom-qmp: Power-on PHY before initialization

From: Stephen Boyd
Date: Wed Nov 22 2017 - 13:03:59 EST


On 11/21/2017 01:23 AM, Manu Gautam wrote:
> PHY must be powered on before turning ON clocks and
> attempting to initialize it. Driver is exposing
> separate init and power_on routines for this.
> Apparently USB dwc3 core driver performs power-on after
> init. Also, poweron and init for QMP PHY need to be

Why does dwc3 driver power on after init? Seems backwards.

> executed together always, hence remove poweron callback
> from phy_ops and explicitly perform this from com_init,

Why do they need to be executed together?

> similar changes needed for poweroff. On similar lines move
> clk_enable from init to com_init which can be called once
> for multi lane PHYs.

Please add parenthesis, clk_enable() for example, to functions so we
know they're functions.

>
> Signed-off-by: Manu Gautam <mgautam@xxxxxxxxxxxxxx>
> ---
> drivers/phy/qualcomm/phy-qcom-qmp.c | 61 +++++++++++++------------------------
> 1 file changed, 21 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
> index 90794dd..2f427e3 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
> @@ -720,33 +720,6 @@ static void qcom_qmp_phy_configure(void __iomem *base,
> }
> }
>
> -static int qcom_qmp_phy_poweron(struct phy *phy)
> -{
> - struct qmp_phy *qphy = phy_get_drvdata(phy);
> - struct qcom_qmp *qmp = qphy->qmp;
> - int num = qmp->cfg->num_vregs;
> - int ret;
> -
> - dev_vdbg(&phy->dev, "Powering on QMP phy\n");
> -
> - /* turn on regulator supplies */
> - ret = regulator_bulk_enable(num, qmp->vregs);
> - if (ret)
> - dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
> -
> - return ret;
> -}
> -
> -static int qcom_qmp_phy_poweroff(struct phy *phy)
> -{
> - struct qmp_phy *qphy = phy_get_drvdata(phy);
> - struct qcom_qmp *qmp = qphy->qmp;
> -
> - regulator_bulk_disable(qmp->cfg->num_vregs, qmp->vregs);
> -
> - return 0;
> -}
> -
> static int qcom_qmp_phy_com_init(struct qcom_qmp *qmp)
> {
> const struct qmp_phy_cfg *cfg = qmp->cfg;
> @@ -759,6 +732,19 @@ static int qcom_qmp_phy_com_init(struct qcom_qmp *qmp)
> return 0;
> }
>
> + /* turn on regulator supplies */
> + ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
> + if (ret) {
> + mutex_unlock(&qmp->phy_mutex);
> + return ret;

This could also be a goto.

> + }
> +
> + ret = clk_bulk_prepare_enable(cfg->num_clks, qmp->clks);
> + if (ret) {
> + dev_err(qmp->dev, "failed to enable clks, err=%d\n", ret);
> + goto err_clk_enable;
> + }
> +
> for (i = 0; i < cfg->num_resets; i++) {
> ret = reset_control_deassert(qmp->resets[i]);
> if (ret) {

--
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