[PATCH RFT 4/7] phy: qcom: qmp-combo: register a typec mux to change the QPHY_MODE

Neil Armstrong neil.armstrong at linaro.org
Thu Feb 29 07:47:46 PST 2024


On 29/02/2024 16:25, Dmitry Baryshkov wrote:
> On Thu, 29 Feb 2024 at 15:08, Neil Armstrong <neil.armstrong at linaro.org> wrote:
>>
>> Register a typec mux in order to change the PHY mode on the Type-C
>> mux events depending on the mode and the svid when in Altmode setup.
>>
>> The DisplayPort phy should be left enabled if is still powered on
>> by the DRM DisplayPort controller, so bail out until the DisplayPort
>> PHY is not powered off.
>>
>> The Type-C Mode/SVID only changes on plug/unplug, and USB SAFE states
>> will be set in between of USB-Only, Combo and DisplayPort Only so
>> this will leave enough time to the DRM DisplayPort controller to
>> turn of the DisplayPort PHY.
> 
> I think this is not fully correct. Please correct me if I'm wrong, but
> it is possible to switch between USB / USB+DP / DP-only at runtime.
> See the Status Update and Configure commands.

Yes, but the current implementation is still valid because we need to
have the DP powered-off before changing the PHY mode.

I never encountered such setup and I have no idea how to test this.

> 
>>
>> Signed-off-by: Neil Armstrong <neil.armstrong at linaro.org>
>> ---
>>   drivers/phy/qualcomm/phy-qcom-qmp-combo.c | 122 ++++++++++++++++++++++++++++--
>>   1 file changed, 117 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
>> index ac5d528fd7a1..b5fb6cbcf867 100644
>> --- a/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-combo.c
>> @@ -19,6 +19,7 @@
>>   #include <linux/reset.h>
>>   #include <linux/slab.h>
>>   #include <linux/usb/typec.h>
>> +#include <linux/usb/typec_dp.h>
>>   #include <linux/usb/typec_mux.h>
>>
>>   #include <drm/bridge/aux-bridge.h>
>> @@ -1515,6 +1516,10 @@ struct qmp_combo {
>>
>>          struct typec_switch_dev *sw;
>>          enum typec_orientation orientation;
>> +
>> +       struct typec_mux_dev *mux;
>> +       unsigned long mux_mode;
>> +       unsigned int svid;
>>   };
>>
>>   static void qmp_v3_dp_aux_init(struct qmp_combo *qmp);
>> @@ -3295,17 +3300,111 @@ static int qmp_combo_typec_switch_set(struct typec_switch_dev *sw,
>>          return 0;
>>   }
>>
>> -static void qmp_combo_typec_unregister(void *data)
>> +static int qmp_combo_typec_mux_set(struct typec_mux_dev *mux, struct typec_mux_state *state)
>> +{
>> +       struct qmp_combo *qmp = typec_mux_get_drvdata(mux);
>> +       const struct qmp_phy_cfg *cfg = qmp->cfg;
>> +       enum qphy_mode new_mode;
>> +       unsigned int svid;
>> +
>> +       if (state->mode == qmp->mode)
>> +               return 0;
>> +
>> +       mutex_lock(&qmp->phy_mutex);
>> +
>> +       if (state->alt)
>> +               svid = state->alt->svid;
>> +       else
>> +               svid = 0; // No SVID
>> +
>> +       if (svid) {
> 
> We should check svid against USB_TYPEC_DP_SID. Otherwise the driver
> will mishandle the USB_SID_PD states.

Ack will do

> 
>> +               switch (state->mode) {
>> +                       /* DP Only */
>> +                       case TYPEC_DP_STATE_C:
>> +                       case TYPEC_DP_STATE_E:
>> +                               new_mode = QPHY_MODE_DP_ONLY;
>> +                               break;
>> +
>> +                               /* DP + USB */
>> +                       case TYPEC_DP_STATE_D:
>> +                       case TYPEC_DP_STATE_F:
>> +                               /* Safe fallback...*/
>> +                       default:
>> +                               new_mode = QPHY_MODE_COMBO;
>> +                               break;
>> +               }
>> +       } else {
>> +               /* Only switch to USB_ONLY when we know we only have USB3 */
>> +               if (qmp->mux_mode == TYPEC_MODE_USB3)
>> +                       new_mode = QPHY_MODE_USB_ONLY;
>> +               else
>> +                       new_mode = QPHY_MODE_COMBO;
>> +       }
>> +
>> +       if (new_mode == qmp->init_mode) {
>> +               dev_dbg(qmp->dev, "typec_mux_set: same phy mode, bail out\n");
>> +               qmp->mode = state->mode;
>> +               goto out;
>> +       }
>> +
>> +       if (qmp->init_mode != QPHY_MODE_USB_ONLY && qmp->dp_powered_on) {
>> +               dev_dbg(qmp->dev, "typec_mux_set: DP is still powered on, delaying switch\n");
>> +               goto out;
>> +       }
>> +
>> +       dev_dbg(qmp->dev, "typec_mux_set: switching from phy mode %d to %d\n",
>> +               qmp->init_mode, new_mode);
>> +
>> +       qmp->mux_mode = state->mode;
>> +       qmp->init_mode = new_mode;
>> +
>> +       if (qmp->init_count) {
>> +               if (qmp->usb_init_count)
>> +                       qmp_combo_usb_power_off(qmp->usb_phy);
>> +               if (qmp->dp_init_count)
>> +                       writel(DP_PHY_PD_CTL_PSR_PWRDN, qmp->dp_dp_phy + QSERDES_DP_PHY_PD_CTL);
>> +               qmp_combo_com_exit(qmp, true);
>> +
>> +               /* Now everything's powered down, power up the right PHYs */
>> +
>> +               qmp_combo_com_init(qmp, true);
>> +               if (qmp->init_mode == QPHY_MODE_DP_ONLY && qmp->usb_init_count) {
>> +                       qmp->usb_init_count--;
>> +               } else if (qmp->init_mode != QPHY_MODE_DP_ONLY) {
>> +                       qmp_combo_usb_power_on(qmp->usb_phy);
>> +                       if (!qmp->usb_init_count)
>> +                               qmp->usb_init_count++;
>> +               }
>> +               if (qmp->init_mode != QPHY_MODE_USB_ONLY && qmp->dp_init_count)
>> +                       cfg->dp_aux_init(qmp);
>> +       }
>> +
>> +out:
>> +       mutex_unlock(&qmp->phy_mutex);
>> +
>> +       return 0;
>> +}
>> +
>> +static void qmp_combo_typec_switch_unregister(void *data)
>>   {
>>          struct qmp_combo *qmp = data;
>>
>>          typec_switch_unregister(qmp->sw);
>>   }
>>
>> -static int qmp_combo_typec_switch_register(struct qmp_combo *qmp)
>> +static void qmp_combo_typec_mux_unregister(void *data)
>> +{
>> +       struct qmp_combo *qmp = data;
>> +
>> +       typec_mux_unregister(qmp->mux);
>> +}
>> +
>> +static int qmp_combo_typec_register(struct qmp_combo *qmp)
>>   {
>>          struct typec_switch_desc sw_desc = {};
>> +       struct typec_mux_desc mux_desc = { };
>>          struct device *dev = qmp->dev;
>> +       int ret;
>>
>>          sw_desc.drvdata = qmp;
>>          sw_desc.fwnode = dev->fwnode;
>> @@ -3316,10 +3415,23 @@ static int qmp_combo_typec_switch_register(struct qmp_combo *qmp)
>>                  return PTR_ERR(qmp->sw);
>>          }
>>
>> -       return devm_add_action_or_reset(dev, qmp_combo_typec_unregister, qmp);
>> +       ret = devm_add_action_or_reset(dev, qmp_combo_typec_switch_unregister, qmp);
>> +       if (ret)
>> +               return ret;
>> +
>> +       mux_desc.drvdata = qmp;
>> +       mux_desc.fwnode = dev->fwnode;
>> +       mux_desc.set = qmp_combo_typec_mux_set;
>> +       qmp->mux = typec_mux_register(dev, &mux_desc);
>> +       if (IS_ERR(qmp->mux)) {
>> +               dev_err(dev, "Unable to register typec mux: %pe\n", qmp->mux);
>> +               return PTR_ERR(qmp->mux);
>> +       }
>> +
>> +       return devm_add_action_or_reset(dev, qmp_combo_typec_mux_unregister, qmp);
>>   }
>>   #else
>> -static int qmp_combo_typec_switch_register(struct qmp_combo *qmp)
>> +static int qmp_combo_typec_register(struct qmp_combo *qmp)
>>   {
>>          return 0;
>>   }
>> @@ -3532,7 +3644,7 @@ static int qmp_combo_probe(struct platform_device *pdev)
>>          if (ret)
>>                  return ret;
>>
>> -       ret = qmp_combo_typec_switch_register(qmp);
>> +       ret = qmp_combo_typec_register(qmp);
>>          if (ret)
>>                  return ret;
>>
>>
>> --
>> 2.34.1
>>
>>
> 
> 




More information about the linux-phy mailing list