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Date:   Mon, 31 Aug 2020 11:07:06 -0700
From:   nguyenb@codeaurora.org
To:     Avri Altman <Avri.Altman@wdc.com>
Cc:     cang@codeaurora.org, asutoshd@codeaurora.org,
        martin.petersen@oracle.com, linux-scsi@vger.kernel.org,
        linux-arm-msm@vger.kernel.org,
        Alim Akhtar <alim.akhtar@samsung.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        Stanley Chu <stanley.chu@mediatek.com>,
        Nitin Rawat <nitirawa@codeaurora.org>,
        Bean Huo <beanhuo@micron.com>,
        Bart Van Assche <bvanassche@acm.org>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1 1/1] scsi: ufshcd: Allow zero value setting to
 Auto-Hibernate Timer
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On 2020-08-29 00:32, Avri Altman wrote:
>> 
>> The zero value Auto-Hibernate Timer is a valid setting, and it
>> indicates the Auto-Hibernate feature being disabled. Correctly
> Right. So " ufshcd_auto_hibern8_enable" is no longer an appropriate 
> name.
> Maybe ufshcd_auto_hibern8_set instead?
Thanks for your comment. I am ok with the name change suggestion.
> 
> Also, did you verified that no other platform relies on its non-zero 
> value?
I only tested the change on Qualcomm's platform. I do not have other 
platforms to do the test.
The UFS host controller spec JESD220E, Section 5.2.5 says
"Software writes “0” to disable Auto-Hibernate Idle Timer". So the spec 
supports this zero value.
Some options:
- We could add a hba->caps so that we only apply the change for 
Qualcomm's platforms.
This is not preferred because it is following the spec implementations.
- Or other platforms that do not support the zero value needs a caps.
> 
> Thanks,
> Avri