Commit c4df6eed authored by Stanley Chu's avatar Stanley Chu Committed by Martin K. Petersen
Browse files

scsi: ufs: Introduce device quirk "DELAY_AFTER_LPM" 

Some UFS devices require delay after VCC power rail is turned off.
Introduce a device quirk "DELAY_AFTER_LPM" to add 5ms delay after VCC
power-off during suspend flow.

Link: https://lore.kernel.org/r/20200729051840.31318-2-stanley.chu@mediatek.com


Reviewed-by: default avatarAndy Teng <andy.teng@mediatek.com>
Reviewed-by: default avatarPeter Wang <peter.wang@mediatek.com>
Reviewed-by: default avatarCan Guo <cang@codeaurora.org>
Acked-by: default avatarAvri Altman <Avri.Altman@wdc.com>
Signed-off-by: default avatarStanley Chu <stanley.chu@mediatek.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent bb2e3314

drivers/scsi/ufs/ufs_quirks.h

+7 −0
Original line number Diff line number Diff line
@@ -109,4 +109,11 @@ struct ufs_dev_fix { 
 */

#define UFS_DEVICE_QUIRK_SUPPORT_EXTENDED_FEATURES (1 << 10)



/*

 * Some UFS devices require delay after VCC power rail is turned-off.

 * Enable this quirk to introduce 5ms delays after VCC power-off during

 * suspend flow.

 */

#define UFS_DEVICE_QUIRK_DELAY_AFTER_LPM        (1 << 11)



#endif /* UFS_QUIRKS_H_ */

drivers/scsi/ufs/ufshcd.c

+11 −0
Original line number Diff line number Diff line
@@ -8107,6 +8107,8 @@ out: 


static void ufshcd_vreg_set_lpm(struct ufs_hba *hba)

{

	bool vcc_off = false;



	/*

	 * It seems some UFS devices may keep drawing more than sleep current

	 * (atleast for 500us) from UFS rails (especially from VCCQ rail).
@@ -8135,13 +8137,22 @@ static void ufshcd_vreg_set_lpm(struct ufs_hba *hba) 
	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&

	    !hba->dev_info.is_lu_power_on_wp) {

		ufshcd_setup_vreg(hba, false);

		vcc_off = true;

	} else if (!ufshcd_is_ufs_dev_active(hba)) {

		ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);

		vcc_off = true;

		if (!ufshcd_is_link_active(hba)) {

			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);

			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq2);

		}

	}



	/*

	 * Some UFS devices require delay after VCC power rail is turned-off.

	 */

	if (vcc_off && hba->vreg_info.vcc &&

		hba->dev_quirks & UFS_DEVICE_QUIRK_DELAY_AFTER_LPM)

		usleep_range(5000, 5100);

}



static int ufshcd_vreg_set_hpm(struct ufs_hba *hba)

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