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

[Konrad Dybcio]

On 2/28/26 11:05 PM, 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@xxxxxxxxxxxx>
> ---
> See https://lore.kernel.org/all/389ca5d3-a698-4dac-911c-39ba057e3d17@xxxxxxxxxxxxxxxx/ for more info.
> BTW https://lore.kernel.org/all/20260205160240.748371-2-loic.poulain@xxxxxxxxxxxxxxxx/ helped with coldplug.
> 
> v2: Reorder disables as suggested
> v1: https://lore.kernel.org/all/20250927093915.45124-2-val@xxxxxxxxxxxx/
> ---
>  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;

I didn't notice this before - please add this hunk

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
index 28428a8d1192..cdcfad2e86b1 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
@@ -3695,7 +3695,7 @@ static int qmp_combo_com_init(struct qmp_combo *qmp, bool force)
        ret = clk_prepare_enable(qmp->pipe_clk);
        if (ret) {
                dev_err(qmp->dev, "pipe_clk enable failed err=%d\n", ret);
-               return ret;
+               goto err_disable_clocks;
        }
 
        qphy_setbits(com, QPHY_V3_DP_COM_POWER_DOWN_CTRL, SW_PWRDN);
@@ -3756,6 +3756,8 @@ static int qmp_combo_com_init(struct qmp_combo *qmp, bool force)
 
        return 0;
 
+err_disable_clocks:
+       clk_bulk_disable_unprepare(qmp->num_clks, qmp->clks);
 err_assert_reset:
        reset_control_bulk_assert(cfg->num_resets, qmp->resets);
 err_disable_regulators:

Konrad