Re: [PATCH v4 11/13] phy: qcom: qmp-usbc: Add USB/DP mutex handling

[Xiangxu Yin <xiangxu.yin@oss.qualcomm.com>]

On 9/12/2025 8:09 PM, Dmitry Baryshkov wrote:
> On Fri, Sep 12, 2025 at 08:03:01PM +0800, Xiangxu Yin wrote:
>> On 9/12/2025 6:32 PM, Dmitry Baryshkov wrote:
>>> On Thu, Sep 11, 2025 at 10:55:08PM +0800, Xiangxu Yin wrote:
>>>> Introduce mutual exclusion between USB and DP PHY modes to prevent
>>>> simultaneous activation.
>>> Describe the problem that you are trying to solve first.
>>
>> Ok.
>>
>>
>>>> Signed-off-by: Xiangxu Yin <xiangxu.yin@oss.qualcomm.com>
>>>> ---
>>>>  drivers/phy/qualcomm/phy-qcom-qmp-usbc.c | 21 +++++++++++++++++++++
>>>>  1 file changed, 21 insertions(+)
>>>>
>>>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c b/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c
>>>> index 613239d15a6a3bba47a647db4e663713f127c93e..866277036089c588cf0c63204efb91bbec5430ae 100644
>>>> --- a/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c
>>>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-usbc.c
>>>> @@ -1061,6 +1061,19 @@ static int qmp_usbc_usb_power_off(struct phy *phy)
>>>>  	return 0;
>>>>  }
>>>>  
>>>> +static int qmp_check_mutex_phy(struct qmp_usbc *qmp, bool is_dp)
>>> mutex has a very well defined use case - a sleeping lock. Please find
>>> some ofther name.
>>
>> Then how about 'qmp_check_exclude_phy'?
>
> qmp_usbc_check_phy_status()?


Ok.


>>
>>>> +{
>>>> +	if ((is_dp && qmp->usb_init_count) ||
>>>> +	    (!is_dp && qmp->dp_init_count)) {
>>>> +		dev_err(qmp->dev,
>>>> +			"PHY is configured for %s, can not enable %s\n",
>>>> +			is_dp ? "USB" : "DP", is_dp ? "DP" : "USB");
>>>> +		return -EBUSY;
>>>> +	}
>>>> +
>>>> +	return 0;
>>>> +}
>>>> +
>>>>  static int qmp_usbc_usb_enable(struct phy *phy)
>>>>  {
>>>>  	struct qmp_usbc *qmp = phy_get_drvdata(phy);