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

Xiangxu Yin posted 13 patches 3 weeks ago
There is a newer version of this series
[PATCH v4 11/13] phy: qcom: qmp-usbc: Add USB/DP mutex handling
Posted by Xiangxu Yin 3 weeks ago 
Introduce mutual exclusion between USB and DP PHY modes to prevent
simultaneous activation.

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)
+{
+	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);
@@ -1068,6 +1081,10 @@ static int qmp_usbc_usb_enable(struct phy *phy)
 
 	mutex_lock(&qmp->phy_mutex);
 
+	ret = qmp_check_mutex_phy(qmp, false);
+	if (ret)
+		goto out_unlock;
+
 	ret = qmp_usbc_com_init(phy);
 	if (ret)
 		goto out_unlock;
@@ -1121,6 +1138,10 @@ static int qmp_usbc_dp_enable(struct phy *phy)
 
 	mutex_lock(&qmp->phy_mutex);
 
+	ret = qmp_check_mutex_phy(qmp, true);
+	if (ret)
+		goto dp_init_unlock;
+
 	ret = qmp_usbc_com_init(phy);
 	if (ret)
 		goto dp_init_unlock;

-- 
2.34.1
Re: [PATCH v4 11/13] phy: qcom: qmp-usbc: Add USB/DP mutex handling
Posted by Dmitry Baryshkov 2 weeks, 6 days ago 
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.

> 
> 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.

> +{
> +	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);

-- 
With best wishes
Dmitry
Re: [PATCH v4 11/13] phy: qcom: qmp-usbc: Add USB/DP mutex handling
Posted by Xiangxu Yin 2 weeks, 6 days ago 
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'?


>> +{
>> +	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);
Re: [PATCH v4 11/13] phy: qcom: qmp-usbc: Add USB/DP mutex handling
Posted by Dmitry Baryshkov 2 weeks, 6 days ago 
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()?

> 
> 
> >> +{
> >> +	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);

-- 
With best wishes
Dmitry
Re: [PATCH v4 11/13] phy: qcom: qmp-usbc: Add USB/DP mutex handling
Posted by Xiangxu Yin 2 weeks, 3 days ago 
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);

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