[PATCH v1] mfd: tps65910: Correct power-off programming sequence

From: Dmitry Osipenko
Date: Thu May 14 2020 - 16:53:17 EST


This patch fixes system shutdown on a devices that use TPS65910 as a
system's power controller. In accordance to the TPS65910 datasheet, the
PMIC's state-machine transitions into the OFF state only when DEV_OFF
bit of DEVCTRL_REG is set. The ON / SLEEP states also should be cleared,
otherwise PMIC won't get into a proper state on shutdown. Devices like
Nexus 7 tablet and Ouya game console are now shutting down properly.

Tested-by: Zack Pearsall <zpearsall@xxxxxxxxx>
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/mfd/tps65910.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c
index 11959021b50a..22116cee411d 100644
--- a/drivers/mfd/tps65910.c
+++ b/drivers/mfd/tps65910.c
@@ -440,8 +440,16 @@ static void tps65910_power_off(void)
DEVCTRL_PWR_OFF_MASK) < 0)
return;

- tps65910_reg_clear_bits(tps65910, TPS65910_DEVCTRL,
- DEVCTRL_DEV_ON_MASK);
+ if (tps65910_reg_clear_bits(tps65910, TPS65910_DEVCTRL,
+ DEVCTRL_DEV_SLP_MASK) < 0)
+ return;
+
+ if (tps65910_reg_clear_bits(tps65910, TPS65910_DEVCTRL,
+ DEVCTRL_DEV_ON_MASK) < 0)
+ return;
+
+ tps65910_reg_set_bits(tps65910, TPS65910_DEVCTRL,
+ DEVCTRL_DEV_OFF_MASK);
}

static int tps65910_i2c_probe(struct i2c_client *i2c,
--
2.26.0