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Date:   Fri, 08 Jan 2021 16:15:11 +0800
From:   ziqichen@codeaurora.org
To:     Can Guo <cang@codeaurora.org>
Cc:     asutoshd@codeaurora.org, nguyenb@codeaurora.org,
        hongwus@codeaurora.org, rnayak@codeaurora.org,
        vinholikatti@gmail.com, jejb@linux.vnet.ibm.com,
        martin.petersen@oracle.com, linux-scsi@vger.kernel.org,
        kernel-team@android.com, saravanak@google.com, salyzyn@google.com,
        kwmad.kim@samsung.com, stanley.chu@mediatek.com,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Avri Altman <avri.altman@wdc.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5 2/2] scsi: ufs-qcom: Fix ufs RST_n specs violation
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 <1610090885-50099-3-git-send-email-ziqichen@codeaurora.org>
 <d7e6a5ed6da3b18be7440e7590f6ef14@codeaurora.org>
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On 2021-01-08 16:05, Can Guo wrote:
> On 2021-01-08 15:28, Ziqi Chen wrote:
>> As per specs, e.g, JESD220E chapter 7.2, while powering
>> off/on the ufs device, RST_n signal should be between
>> VSS(Ground) and VCCQ/VCCQ2.
>> 
>> Signed-off-by: Ziqi Chen <ziqichen@codeaurora.org>
>> ---
>>  drivers/scsi/ufs/ufs-qcom.c | 4 ++++
>>  1 file changed, 4 insertions(+)
>> 
>> diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
>> index 2206b1e..d8b896c 100644
>> --- a/drivers/scsi/ufs/ufs-qcom.c
>> +++ b/drivers/scsi/ufs/ufs-qcom.c
>> @@ -582,6 +582,10 @@ static int ufs_qcom_suspend(struct ufs_hba *hba,
>> enum ufs_pm_op pm_op)
>>  		ufs_qcom_disable_lane_clks(host);
>>  		phy_power_off(phy);
>> 
>> +		/* reset the connected UFS device during power down */
>> +		if (host->device_reset)
>> +			gpiod_set_value_cansleep(host->device_reset, 1);
>> +
> 
> Instead of calling gpiod_set_value(1/0) directly,
> can we have a wrapper func for it?
> 
> Thanks,
> Can Guo.

Sure, it'll be better that way.

Best Regards,
Ziqi

> 
>>  	} else if (!ufs_qcom_is_link_active(hba)) {
>>  		ufs_qcom_disable_lane_clks(host);
>>  	}