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

Xiangxu Yin xiangxu.yin at oss.qualcomm.com
Fri Sep 12 05:03:01 PDT 2025


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 at 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'?


>> +{
>> +	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);



More information about the linux-phy mailing list