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From:   Avri Altman <Avri.Altman@wdc.com>
To:     Asutosh Das <asutoshd@codeaurora.org>,
        "cang@codeaurora.org" <cang@codeaurora.org>,
        "martin.petersen@oracle.com" <martin.petersen@oracle.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>
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        Steven Rostedt <rostedt@goodmis.org>,
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        open list <linux-kernel@vger.kernel.org>
Subject: RE: [RFC PATCH v3 1/1] scsi: ufs: Enable power management for wlun
Thread-Topic: [RFC PATCH v3 1/1] scsi: ufs: Enable power management for wlun
Thread-Index: AQHXAKrEeNNZ6E03PU2kp7215n4xZKpWndRQ
Date:   Sat, 13 Feb 2021 21:37:29 +0000
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> +       } else {
Is it possible to get here?
Scsi_scan_host is called only after successful add_wluns

> +               /* device wlun is probed */
> +               hba->luns_avail--;
> +       }
> +}
> +


>=20
>  /**
> @@ -7254,6 +7312,14 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba
> *hba)
>                 goto out;
>         }
>         ufshcd_blk_pm_runtime_init(hba->sdev_ufs_device);
> +       /*
> +        * A pm_runtime_put_sync is invoked when this device enables
> blk_pm_runtime
> +        * & would suspend the device-wlun upon timer expiry.
> +        * But suspending device wlun _may_ put the ufs device in the pre=
-defined
> +        * low power mode (SSU <rpm_lvl>). Probing of other luns may fail=
 then.
> +        * Don't allow this suspend until all the luns have been probed.
Maybe add one more sentence: see pm_runtime_mark_last_busy in ufshcd_setup_=
links


> -       ufshcd_clear_ua_wluns(hba);
Are there any callers left to ufshcd_clear_ua_wluns?
Can it be removed?

> +       if (hba->wlun_dev_clr_ua)
> +               ufshcd_clear_ua_wlun(hba, UFS_UPIU_UFS_DEVICE_WLUN);
>=20
>         cmd[4] =3D pwr_mode << 4;