The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 24e2e7a19f7e4b83d0d5189040d997bce3596473 Mon Sep 17 00:00:00 2001
From: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Date: Wed, 12 Jun 2019 23:19:05 +0800
Subject: [PATCH] scsi: ufs: Avoid runtime suspend possibly being blocked
forever
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@xxxxxxxxxxxxxxx
Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Reviewed-by: Avri Altman <avri.altman@xxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
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:
