| Message ID | 1560352745-24681-1-git-send-email-stanley.chu@mediatek.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Commit | 24e2e7a19f7e4b83d0d5189040d997bce3596473 |
| Headers | show |
| Series | [v2] scsi: ufs: Avoid runtime suspend possibly being blocked forever | expand |
> > UFS runtime suspend can be triggered after pm_runtime_enable() > is invoked in ufshcd_pltfrm_init(). However if the first runtime > suspend is triggered before binding ufs_hba structure to ufs > device structure via platform_set_drvdata(), then UFS runtime > suspend will be no longer triggered in the future because its > dev->power.runtime_error was set in the first triggering and does > not have any chance to be cleared. > > To be more clear, dev->power.runtime_error is set if hba is NULL > in ufshcd_runtime_suspend() which returns -EINVAL to rpm_callback() > where dev->power.runtime_error is set as -EINVAL. In this case, any > future rpm_suspend() for UFS device fails because > rpm_check_suspend_allowed() fails due to non-zero > dev->power.runtime_error. > > To resolve this issue, make sure the first UFS runtime suspend > get valid "hba" in ufshcd_runtime_suspend(): Enable UFS runtime PM > only after hba is successfully bound to UFS device structure. > > Fixes: 62694735ca95 ([SCSI] ufs: Add runtime PM support for UFS host > controller driver) > Cc: stable@vger.kernel.org > Signed-off-by: Stanley Chu <stanley.chu@mediatek.com> Reviewed-by: Avri Altman <avri.altman@wdc.com>
Stanley, > UFS runtime suspend can be triggered after pm_runtime_enable() > is invoked in ufshcd_pltfrm_init(). However if the first runtime > suspend is triggered before binding ufs_hba structure to ufs > device structure via platform_set_drvdata(), then UFS runtime > suspend will be no longer triggered in the future because its > dev->power.runtime_error was set in the first triggering and does > not have any chance to be cleared. Applied to 5.2/scsi-fixes. Thanks!
diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c index 8a74ec30c3d2..d7d521b394c3 100644 --- a/drivers/scsi/ufs/ufshcd-pltfrm.c +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c @@ -430,24 +430,21 @@ int ufshcd_pltfrm_init(struct platform_device *pdev, goto dealloc_host; } - pm_runtime_set_active(&pdev->dev); - pm_runtime_enable(&pdev->dev); - ufshcd_init_lanes_per_dir(hba); err = ufshcd_init(hba, mmio_base, irq); if (err) { dev_err(dev, "Initialization failed\n"); - goto out_disable_rpm; + goto dealloc_host; } platform_set_drvdata(pdev, hba); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + return 0; -out_disable_rpm: - pm_runtime_disable(&pdev->dev); - pm_runtime_set_suspended(&pdev->dev); dealloc_host: ufshcd_dealloc_host(hba); out:
UFS runtime suspend can be triggered after pm_runtime_enable() is invoked in ufshcd_pltfrm_init(). However if the first runtime suspend is triggered before binding ufs_hba structure to ufs device structure via platform_set_drvdata(), then UFS runtime suspend will be no longer triggered in the future because its dev->power.runtime_error was set in the first triggering and does not have any chance to be cleared. To be more clear, dev->power.runtime_error is set if hba is NULL in ufshcd_runtime_suspend() which returns -EINVAL to rpm_callback() where dev->power.runtime_error is set as -EINVAL. In this case, any future rpm_suspend() for UFS device fails because rpm_check_suspend_allowed() fails due to non-zero dev->power.runtime_error. To resolve this issue, make sure the first UFS runtime suspend get valid "hba" in ufshcd_runtime_suspend(): Enable UFS runtime PM only after hba is successfully bound to UFS device structure. Fixes: 62694735ca95 ([SCSI] ufs: Add runtime PM support for UFS host controller driver) Cc: stable@vger.kernel.org Signed-off-by: Stanley Chu <stanley.chu@mediatek.com> --- drivers/scsi/ufs/ufshcd-pltfrm.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)