Re: [PATCH v4 4/4] phy: qcom-qmp: Use proper PWRDOWN offset for sm8150 USB

[Wesley Cheng]

Hi Manu,

Thanks for the feedback and review.

On 4/2/2020 12:35 AM, Manu Gautam wrote:
> 
> On 3/31/2020 1:06 AM, Wesley Cheng wrote:
>> The register map for SM8150 QMP USB SSPHY has moved
>> QPHY_POWER_DOWN_CONTROL to a different offset.  Allow for
>> an offset in the register table to override default value
>> if it is a DP capable PHY.
>>
>> Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>
>> ---
>>  drivers/phy/qualcomm/phy-qcom-qmp.c | 15 ++++++++++++---
>>  1 file changed, 12 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
>> index cc04471..4c0517e 100644
>> --- a/drivers/phy/qualcomm/phy-qcom-qmp.c
>> +++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
>> @@ -164,6 +164,7 @@ enum qphy_reg_layout {
>>  	[QPHY_SW_RESET]			= 0x00,
>>  	[QPHY_START_CTRL]		= 0x44,
>>  	[QPHY_PCS_STATUS]		= 0x14,
>> +	[QPHY_COM_POWER_DOWN_CONTROL]	= 0x40,
> Since this is in PCS block please rename it to -
> 
> QPHY_PCS_POWER_DOWN_CONTROL
> 

Sure, will add another enum value to the register layout, and rename it
where needed.

>>  };
>>  
>>  static const unsigned int sdm845_ufsphy_regs_layout[] = {
>> @@ -1627,6 +1628,9 @@ static int qcom_qmp_phy_com_init(struct qmp_phy *qphy)
>>  	if (cfg->has_phy_com_ctrl)
>>  		qphy_setbits(serdes, cfg->regs[QPHY_COM_POWER_DOWN_CONTROL],
>>  			     SW_PWRDN);
>> +	else if (cfg->has_phy_dp_com_ctrl && cfg->regs[QPHY_COM_POWER_DOWN_CONTROL])
>> +		qphy_setbits(pcs, cfg->regs[QPHY_COM_POWER_DOWN_CONTROL],
>> +			     cfg->pwrdn_ctrl);
>>  	else
>>  		qphy_setbits(pcs, QPHY_POWER_DOWN_CONTROL, cfg->pwrdn_ctrl);
> Since, this register is in PCS block why check for dp_com_ctrl here?
> Something like:
> 
>  	if (cfg->has_phy_com_ctrl) {
>  		qphy_setbits(serdes, cfg->regs[QPHY_COM_POWER_DOWN_CONTROL],
>  			     SW_PWRDN);
> 	} else {
> 		if (cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL]) 
> 			qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL],
> 			     cfg->pwrdn_ctrl);
>  		else
>  			qphy_setbits(pcs, QPHY_POWER_DOWN_CONTROL, cfg->pwrdn_ctrl);
> 	}
> 

Agree with this.

>>  
>> @@ -1671,10 +1675,12 @@ static int qcom_qmp_phy_com_init(struct qmp_phy *qphy)
>>  	return ret;
>>  }
>>  
>> -static int qcom_qmp_phy_com_exit(struct qcom_qmp *qmp)
>> +static int qcom_qmp_phy_com_exit(struct qmp_phy *qphy)
>>  {
>> +	struct qcom_qmp *qmp = qphy->qmp;
>>  	const struct qmp_phy_cfg *cfg = qmp->cfg;
>>  	void __iomem *serdes = qmp->serdes;
>> +	void __iomem *pcs = qphy->pcs;
>>  	int i = cfg->num_resets;
>>  
>>  	mutex_lock(&qmp->phy_mutex);
>> @@ -1691,6 +1697,9 @@ static int qcom_qmp_phy_com_exit(struct qcom_qmp *qmp)
>>  			     SW_RESET);
>>  		qphy_setbits(serdes, cfg->regs[QPHY_COM_POWER_DOWN_CONTROL],
>>  			     SW_PWRDN);
>> +	} else if (cfg->has_phy_dp_com_ctrl && cfg->regs[QPHY_COM_POWER_DOWN_CONTROL]) {
> 
> Can we add change similar to init() here ?
> 
> 

Sure.  I will move this check to where the current code writes to the
PWR DOWN CONTROL in

static int qcom_qmp_phy_disable(struct phy *phy)
{
	...
	qphy_clrbits(qphy->pcs, QPHY_POWER_DOWN_CONTROL, cfg->pwrdn_ctrl);

We wouldn't want the SW to write to an incorrect register.

>> +			     cfg->pwrdn_ctrl);
>>  	}
>>  
>>  	while (--i >= 0)
>> @@ -1829,7 +1838,7 @@ static int qcom_qmp_phy_enable(struct phy *phy)
>>  	if (cfg->has_lane_rst)
>>  		reset_control_assert(qphy->lane_rst);
>>  err_lane_rst:
>> -	qcom_qmp_phy_com_exit(qmp);
>> +	qcom_qmp_phy_com_exit(qphy);
>>  
>>  	return ret;
>>  }
>> @@ -1855,7 +1864,7 @@ static int qcom_qmp_phy_disable(struct phy *phy)
>>  	if (cfg->has_lane_rst)
>>  		reset_control_assert(qphy->lane_rst);
>>  
>> -	qcom_qmp_phy_com_exit(qmp);
>> +	qcom_qmp_phy_com_exit(qphy);
>>  
>>  	qmp->phy_initialized = false;
>>  
> 

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