Hi Peter,
On Wed, 2021-05-12 at 18:01 +0800, peter.wang@xxxxxxxxxxxx wrote:
> From: Peter Wang <peter.wang@xxxxxxxxxxxx>
>
> As per specs, e.g, JESD220E chapter 7.2, while powering off
> the ufs device, RST_N signal should be between VSS(Ground)
> and VCCQ/VCCQ2. The power down sequence after fixing as below:
>
> Power down:
> 1. Assert RST_N low
> 2. Turn-off VCC
> 3. Turn-off VCCQ/VCCQ2
>
> Signed-off-by: Peter Wang <peter.wang@xxxxxxxxxxxx>
> ---
> drivers/scsi/ufs/ufs-mediatek.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
> index c55202b..47b4066 100644
> --- a/drivers/scsi/ufs/ufs-mediatek.c
> +++ b/drivers/scsi/ufs/ufs-mediatek.c
> @@ -922,6 +922,7 @@ static void ufs_mtk_vreg_set_lpm(struct ufs_hba *hba, bool lpm)
> static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> {
> int err;
> + struct arm_smccc_res res;
>
> if (ufshcd_is_link_hibern8(hba)) {
> err = ufs_mtk_link_set_lpm(hba);
> @@ -941,6 +942,9 @@ static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
> goto fail;
> }
>
> + if (ufshcd_is_link_off(hba))
> + ufs_mtk_device_reset_ctrl(0, res);
> +
For the case "linkoff @ suspend", HW reset pin can be de-asserted via
ufshcd_resume() -> ufshcd_reset_and_restore() ->
ufshcd_vops_device_reset(), so this looks good to me.
Reviewed-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
