• Can Guo's avatar
    scsi: ufs: Enable block layer runtime PM for well-known logical units · fb276f77
    Can Guo authored
    Block layer RPM is enabled for the genernal UFS SCSI devices when they are
    probed by their driver. However block layer RPM is not enabled for UFS
    well-known SCSI devices.
    
    As UFS SCSI devices have their corresponding BSG char devices, accessing a
    BSG char device via IOCTL may send requests to its corresponding SCSI
    device through its request queue. If BSG IOCTL sends a request to a
    well-known SCSI device when HBA is not runtime active, due to block layer
    RPM not being enabled for the well-known SCSI devices, the HBA, which is at
    the top of a SCSI device's parent chain, will not be resumed.
    
    This change enables block layer RPM for the well-known SCSI devices so that
    block layer can handle RPM for the well-known SCSI devices just like for
    the general SCSI devices.
    Reviewed-by: default avatarAvri Altman <avri.altman@wdc.com>
    Reviewed-by: default avatarStanley Chu <stanley.chu@mediatek.com>
    Signed-off-by: default avatarCan Guo <cang@codeaurora.org>
    Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
    fb276f77
ufshcd.c 228 KB