Hi,
>
> 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: e3ce73d (scsi: ufs: fix bugs related to null pointer access and array
> size)
This code was inserted before platform_set_drvdata in
6269473 [SCSI] ufs: Add runtime PM support for UFS host controller driver.
Why do you point to e3ce73d?
Thanks,
Avri
> Cc: sta...@vger.kernel.org
> Signed-off-by: Stanley Chu <stanley....@mediatek.com>
> ---
> drivers/scsi/ufs/ufshcd-pltfrm.c | 11 ++++-------
> 1 file changed, 4 insertions(+), 7 deletions(-)
>
> 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:
> --
> 2.18.0
