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Subject: Re: [PATCH v4 01/10] scsi: ufs: Rename flags pm_op_in_progress and
 is_sys_suspended
To:     "Rafael J. Wysocki" <rafael@kernel.org>
Cc:     Can Guo <cang@codeaurora.org>, asutoshd@codeaurora.org,
        nguyenb@codeaurora.org, hongwus@codeaurora.org,
        ziqichen@codeaurora.org, linux-scsi@vger.kernel.org,
        kernel-team@android.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>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Stanley Chu <stanley.chu@mediatek.com>,
        Bean Huo <beanhuo@micron.com>,
        Jaegeuk Kim <jaegeuk@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Kiwoong Kim <kwmad.kim@samsung.com>,
        Satya Tangirala <satyat@google.com>,
        "open list:ARM/QUALCOMM SUPPORT" <linux-arm-msm@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
References: <1624433711-9339-1-git-send-email-cang@codeaurora.org>
 <1624433711-9339-2-git-send-email-cang@codeaurora.org>
 <cb39c5d7-c21d-66b1-0a86-f9154f73a94e@acm.org>
 <b7562bc820fc712196104a5eae30e2e4@codeaurora.org>
From:   Bart Van Assche <bvanassche@acm.org>
Message-ID: <50023fb6-7b61-e5dd-9fac-e0be3adbbadc@acm.org>
Date:   Mon, 28 Jun 2021 10:07:40 -0700
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On 6/28/21 12:01 AM, Can Guo wrote:
> On 2021-06-25 07:42, Bart Van Assche wrote:
>> On 6/23/21 12:35 AM, Can Guo wrote:
>>> Rename pm_op_in_progress and is_sys_suspended to
>>> wlu_pm_op_in_progress and
>>> is_wlu_sys_suspended accordingly.
>>
>> Can the is_wlu_sys_suspended member variable be removed by checking
>> dev->power.is_suspended where dev represents the WLUN?
>>
> 
> No, PM set dev->power.is_suspended to "false" even the device failed
> resuming,
> while is_wlu_sys_suspended can be used to tell that.

(+Rafael)

Hi Rafael,

In drivers/base/power/main.c we found the following code:

 End:
	error = dpm_run_callback(callback, dev, state, info);
	dev->power.is_suspended = false;

Is it a bug or a feature that dev->power.is_suspended is set to false if
dpm_run_callback() fails? I'm asking this because only clearing
dev->power.is_suspended if dpm_run_callback() returns 0 would allow to
simplify the UFS driver. It can happen for UFS devices that runtime
resume fails and if this fails we need to track this.

Thanks,

Bart.