Re: [PATCH V2 2/3] scsi: ufs: add a vops to configure VCC voltage level

[nitirawa@codeaurora.org]

On 2021-03-31 23:30, Asutosh Das (asd) wrote:
> On 3/21/2021 2:57 PM, Nitin Rawat wrote:
>> Add a vops to configure VCC voltage VCC voltage level
>> for platform supporting both ufs2.x and ufs 3.x devices.
>> 
>> Suggested-by: Stanley Chu <stanley.chu@mediatek.com>
>> Suggested-by: Asutosh Das <asutoshd@codeaurora.org>
>> Suggested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
>> Signed-off-by: Nitin Rawat <nitirawa@codeaurora.org>
>> Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
>> ---
>>   drivers/scsi/ufs/ufshcd.c |  4 ++++
>>   drivers/scsi/ufs/ufshcd.h | 10 ++++++++++
>>   2 files changed, 14 insertions(+)
>> 
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index 633ca8e..5bfe987 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -7763,6 +7763,10 @@ static int ufshcd_add_lus(struct ufs_hba *hba)
>>   		goto out;
>> 
>>   	ufshcd_clear_ua_wluns(hba);
>> +	if (ufshcd_vops_setup_vcc_regulators(hba))
> This would be invoked even for platforms that don't support both 2.x
> and 3.x and don't need to set the voltages in the driver.
> I guess platforms that support both 2.x and 3.x and can't set the
> regulator voltages from dts due to different voltage requirements of
> 2.x and 3.x, should request the driver to set the voltages. And the
> driver may do so after determining the device version.
> 
>> +		dev_err(hba->dev,
>> +			"%s: Failed to set the VCC regulator values, continue with 
>> 2.7v\n",
>> +			__func__);
>> 
>>   	/* Initialize devfreq after UFS device is detected */
>>   	if (ufshcd_is_clkscaling_supported(hba)) {
>> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
>> index 0db796a..8f0945d 100644
>> --- a/drivers/scsi/ufs/ufshcd.h
>> +++ b/drivers/scsi/ufs/ufshcd.h
>> @@ -324,6 +324,7 @@ struct ufs_pwr_mode_info {
>>    * @device_reset: called to issue a reset pulse on the UFS device
>>    * @program_key: program or evict an inline encryption key
>>    * @event_notify: called to notify important events
>> + * @setup_vcc_regulators : update vcc regulator level
>>    */
>>   struct ufs_hba_variant_ops {
>>   	const char *name;
>> @@ -360,6 +361,7 @@ struct ufs_hba_variant_ops {
>>   			       const union ufs_crypto_cfg_entry *cfg, int slot);
>>   	void	(*event_notify)(struct ufs_hba *hba,
>>   				enum ufs_event_type evt, void *data);
>> +	int    (*setup_vcc_regulators)(struct ufs_hba *hba);
>>   };
>> 
>>   /* clock gating state  */
>> @@ -1269,6 +1271,14 @@ static inline void 
>> ufshcd_vops_config_scaling_param(struct ufs_hba *hba,
>>   		hba->vops->config_scaling_param(hba, profile, data);
>>   }
>> 
>> +static inline int ufshcd_vops_setup_vcc_regulators(struct ufs_hba 
>> *hba)
>> +{
>> +	if (hba->vops && hba->vops->setup_vcc_regulators)
>> +		return hba->vops->setup_vcc_regulators(hba);
>> +
>> +	return 0;
>> +}
>> +
>>   extern struct ufs_pm_lvl_states ufs_pm_lvl_states[];
>> 
>>   /*
>> --
>> 2.7.4
>> 

Hi Asutosh,
Thanks for the suggestion. I will check and try to accommodate your 
suggestion.
Regards,
Nitin