From 488edafb1120f715bebd80b6fe4089f83fb082b2 Mon Sep 17 00:00:00 2001 From: Stanley Chu Date: Mon, 1 Jun 2020 18:46:44 +0800 Subject: [PATCH] scsi: ufs-mediatek: Introduce low-power mode for device power supply Allow device power supply to enter low-power mode. Link: https://lore.kernel.org/r/20200601104646.15436-4-stanley.chu@mediatek.com Reviewed-by: Pengshun Zhao Signed-off-by: Stanley Chu Signed-off-by: Martin K. Petersen --- drivers/scsi/ufs/ufs-mediatek.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c index 3c85f5e97dea..5f41b7b7db8f 100644 --- a/drivers/scsi/ufs/ufs-mediatek.c +++ b/drivers/scsi/ufs/ufs-mediatek.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include "ufshcd.h" @@ -521,6 +522,19 @@ static int ufs_mtk_link_set_lpm(struct ufs_hba *hba) return 0; } +static void ufs_mtk_vreg_set_lpm(struct ufs_hba *hba, bool lpm) +{ + if (!hba->vreg_info.vccq2) + return; + + if (lpm & !hba->vreg_info.vcc->enabled) + regulator_set_mode(hba->vreg_info.vccq2->reg, + REGULATOR_MODE_IDLE); + else if (!lpm) + regulator_set_mode(hba->vreg_info.vccq2->reg, + REGULATOR_MODE_NORMAL); +} + static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) { int err; @@ -537,6 +551,12 @@ static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) ufshcd_set_link_off(hba); return -EAGAIN; } + /* + * Make sure no error will be returned to prevent + * ufshcd_suspend() re-enabling regulators while vreg is still + * in low-power mode. + */ + ufs_mtk_vreg_set_lpm(hba, true); } if (!ufshcd_is_link_active(hba)) @@ -554,6 +574,7 @@ static int ufs_mtk_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op) phy_power_on(host->mphy); if (ufshcd_is_link_hibern8(hba)) { + ufs_mtk_vreg_set_lpm(hba, false); err = ufs_mtk_link_set_hpm(hba); if (err) { err = ufshcd_link_recovery(hba); -- 2.25.1