[PATCH v1] soc: mediatek: pm-domains: Fix the power glitch issue

Chun-Jie Chen chun-jie.chen at mediatek.com
Wed Mar 9 17:15:48 PST 2022


Power reset maybe generate unexpected signal. In order to avoid
the glitch issue, we need to enable isolation first to guarantee the
stable signal when power reset is triggered.

Fixes: 59b644b01cf4 ("soc: mediatek: Add MediaTek SCPSYS power domains")
Signed-off-by: Chun-Jie Chen <chun-jie.chen at mediatek.com>
---
This patch is based on 5.17-rc1.
---
 drivers/soc/mediatek/mtk-pm-domains.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soc/mediatek/mtk-pm-domains.c b/drivers/soc/mediatek/mtk-pm-domains.c
index b762bc40f56b..0195f6c3396b 100644
--- a/drivers/soc/mediatek/mtk-pm-domains.c
+++ b/drivers/soc/mediatek/mtk-pm-domains.c
@@ -272,9 +272,9 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
 	clk_bulk_disable_unprepare(pd->num_subsys_clks, pd->subsys_clks);
 
 	/* subsys power off */
-	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT);
 	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ISO_BIT);
 	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_CLK_DIS_BIT);
+	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT);
 	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_2ND_BIT);
 	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_BIT);
 
-- 
2.18.0




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