> From: Zhe Wang <zhe.wang1@xxxxxxxxxx>
>
> Some UFS devices require that the VCC should drop below 0.1V after
> turning off, otherwise device may not resume successfully. And
> because the power-off rate is different on different SOC platforms.
> Therefore, we hope that the delay can be modified by vendor to
> adjust the most appropriate delay value.
>
> Signed-off-by: Zhe Wang <zhe.wang1@xxxxxxxxxx>
> ---
> V1 -> V2
> - move turnoff_delay_us to struct ufs_vreg instead
> - replace usleep_range with ufshcd_delay_us
>
> drivers/ufs/core/ufshcd.c | 9 ++++++++-
> include/ufs/ufs.h | 1 +
> 2 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index 7256e6c43ca6..386ff6ed2f20 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -89,6 +89,9 @@
> /* Polling time to wait for fDeviceInit */
> #define FDEVICEINIT_COMPL_TIMEOUT 1500 /* millisecs */
>
> +/* Default value of turn off VCC rail: 5000us */
> +#define UFS_VCC_TURNOFF_DELAY_US 5000
> +
> #define ufshcd_toggle_vreg(_dev, _vreg, _on) \
> ({ \
> int _ret; \
> @@ -7784,6 +7787,10 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
>
> ufs_fixup_device_setup(hba);
>
> + if (hba->dev_quirks & UFS_DEVICE_QUIRK_DELAY_AFTER_LPM &&
> + !hba->vreg_info.vcc->turnoff_delay_us)
> + hba->vreg_info.vcc->turnoff_delay_us =
> UFS_VCC_TURNOFF_DELAY_US;
> +
You answered my question to your v1 - where otherwise you are setting this value:
"We are still preparing and discussing our own UFS host driver code,
which will be uploaded once we are done."
Well until then - this isn't very useful.
Thanks,
Avri
> ufshcd_wb_probe(hba, desc_buf);
>
> ufshcd_temp_notif_probe(hba, desc_buf);
> @@ -8918,7 +8925,7 @@ static void ufshcd_vreg_set_lpm(struct ufs_hba *hba)
> */
> if (vcc_off && hba->vreg_info.vcc &&
> hba->dev_quirks & UFS_DEVICE_QUIRK_DELAY_AFTER_LPM)
> - usleep_range(5000, 5100);
> + ufshcd_delay_us(hba->vreg_info.vcc->turnoff_delay_us, 100);
> }
>
> #ifdef CONFIG_PM
> diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
> index 1bba3fead2ce..792335dfd70b 100644
> --- a/include/ufs/ufs.h
> +++ b/include/ufs/ufs.h
> @@ -569,6 +569,7 @@ struct ufs_vreg {
> bool always_on;
> bool enabled;
> int max_uA;
> + u32 turnoff_delay_us;
> };
>
> struct ufs_vreg_info {
> --
> 2.17.1
