[PATCH v5 06/11] scsi: ufs-mediatek: Support low-power mode for VCCQ

From: Stanley Chu
Date: Thu Jun 16 2022 - 01:37:48 EST


From: Peter Wang <peter.wang@xxxxxxxxxxxx>

Also allow VCCQ to enter low-power mode, and meanwhile
remove the restriction of VCC because VCCQ/VCCQ2 can
be changed to low-power mode even if VCC keeps on while
the device is not in active power mode.

Reviewed-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Signed-off-by: Peter Wang <peter.wang@xxxxxxxxxxxx>
Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
---
drivers/ufs/host/ufs-mediatek.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/ufs/host/ufs-mediatek.c b/drivers/ufs/host/ufs-mediatek.c
index 03762ecaaaf8..65a2a4185ef6 100755
--- a/drivers/ufs/host/ufs-mediatek.c
+++ b/drivers/ufs/host/ufs-mediatek.c
@@ -1031,7 +1031,13 @@ static int ufs_mtk_link_set_lpm(struct ufs_hba *hba)

static void ufs_mtk_vreg_set_lpm(struct ufs_hba *hba, bool lpm)
{
- if (!hba->vreg_info.vccq2 || !hba->vreg_info.vcc)
+ struct ufs_vreg *vccqx = NULL;
+
+ if (!hba->vreg_info.vccq && !hba->vreg_info.vccq2)
+ return;
+
+ /* Skip if VCC is assumed always-on */
+ if (!hba->vreg_info.vcc)
return;

/* Bypass LPM when device is still active */
@@ -1042,12 +1048,13 @@ static void ufs_mtk_vreg_set_lpm(struct ufs_hba *hba, bool lpm)
if (lpm && hba->vreg_info.vcc->enabled)
return;

- if (lpm)
- regulator_set_mode(hba->vreg_info.vccq2->reg,
- REGULATOR_MODE_IDLE);
+ if (hba->vreg_info.vccq)
+ vccqx = hba->vreg_info.vccq;
else
- regulator_set_mode(hba->vreg_info.vccq2->reg,
- REGULATOR_MODE_NORMAL);
+ vccqx = hba->vreg_info.vccq2;
+
+ regulator_set_mode(vccqx->reg,
+ lpm ? REGULATOR_MODE_IDLE : REGULATOR_MODE_NORMAL);
}

static void ufs_mtk_auto_hibern8_disable(struct ufs_hba *hba)
--
2.18.0