[PATCH v2] phy: qcom: qmp-combo: Move pipe_clk on/off to common

Neil Armstrong neil.armstrong at linaro.org
Mon Mar 2 01:45:16 PST 2026


On 2/28/26 23:05, Val Packett wrote:
> Keep the USB pipe clock working when the phy is in DP-only mode, because
> the dwc controller still needs it for USB 2.0 over the same Type-C port.
> 
> Tested with the BenQ RD280UA monitor which has a downstream-facing port
> for data passthrough that's manually switchable between USB 2 and 3,
> corresponding to 4-lane and 2-lane DP respectively.
> 
> Note: the suspend/resume callbacks were already gating the enable/disable
> of this clock only on init_count and not usb_init_count!
> 
> Signed-off-by: Val Packett <val at packett.cool>
> ---
> See https://lore.kernel.org/all/389ca5d3-a698-4dac-911c-39ba057e3d17@oss.qualcomm.com/ for more info.
> BTW https://lore.kernel.org/all/20260205160240.748371-2-loic.poulain@oss.qualcomm.com/ helped with coldplug.
> 
> v2: Reorder disables as suggested
> v1: https://lore.kernel.org/all/20250927093915.45124-2-val@packett.cool/
> ---
>   drivers/phy/qualcomm/phy-qcom-qmp-combo.c | 16 ++++++++--------
>   1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> index 93f1aa10d400..28428a8d1192 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
> @@ -3691,6 +3691,13 @@ static int qmp_combo_com_init(struct qmp_combo *qmp, bool force)
>   	if (ret)
>   		goto err_assert_reset;
>   
> +	/* In DP-only mode, the pipe clk is still required for USB2 */
> +	ret = clk_prepare_enable(qmp->pipe_clk);
> +	if (ret) {
> +		dev_err(qmp->dev, "pipe_clk enable failed err=%d\n", ret);
> +		return ret;
> +	}
> +
>   	qphy_setbits(com, QPHY_V3_DP_COM_POWER_DOWN_CTRL, SW_PWRDN);
>   
>   	/* override hardware control for reset of qmp phy */
> @@ -3768,6 +3775,7 @@ static int qmp_combo_com_exit(struct qmp_combo *qmp, bool force)
>   
>   	reset_control_bulk_assert(cfg->num_resets, qmp->resets);
>   
> +	clk_disable_unprepare(qmp->pipe_clk);
>   	clk_bulk_disable_unprepare(qmp->num_clks, qmp->clks);
>   
>   	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
> @@ -3871,12 +3879,6 @@ static int qmp_combo_usb_power_on(struct phy *phy)
>   
>   	qmp_configure(qmp->dev, serdes, cfg->serdes_tbl, cfg->serdes_tbl_num);
>   
> -	ret = clk_prepare_enable(qmp->pipe_clk);
> -	if (ret) {
> -		dev_err(qmp->dev, "pipe_clk enable failed err=%d\n", ret);
> -		return ret;
> -	}
> -
>   	/* Tx, Rx, and PCS configurations */
>   	qmp_configure_lane(qmp->dev, tx, cfg->tx_tbl, cfg->tx_tbl_num, 1);
>   	qmp_configure_lane(qmp->dev, tx2, cfg->tx_tbl, cfg->tx_tbl_num, 2);
> @@ -3922,8 +3924,6 @@ static int qmp_combo_usb_power_off(struct phy *phy)
>   	struct qmp_combo *qmp = phy_get_drvdata(phy);
>   	const struct qmp_phy_cfg *cfg = qmp->cfg;
>   
> -	clk_disable_unprepare(qmp->pipe_clk);
> -
>   	/* PHY reset */
>   	qphy_setbits(qmp->pcs, cfg->regs[QPHY_SW_RESET], SW_RESET);
>   

Reviewed-by: Neil Armstrong <neil.armstrong at linaro.org>

Thanks,
Neil



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