Correct power-off programming sequence in order to fix shutting down devices which are using TPS65910 PMIC.
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 shutting down properly now. Tested-by: Peter Geis <pgwipe...@gmail.com> Tested-by: Zack Pearsall <zpears...@yahoo.com> Signed-off-by: Dmitry Osipenko <dig...@gmail.com> --- Changelog: v4: - Rebased on a recent linux-next. v3: - Removed the DEV_SLP_MASK clearing and adding clarifying comment to the code about why clearing PWR_OFF bit needs to be done, which was suggested by Michał Mirosław in a review comment to v2. - Added tested-by from Peter Geis who tested v3 on his Ouya game console. v2: - Now using a single tps65910_reg_update_bits() instead of set+clear. Thanks to Michał Mirosław for the suggestion. drivers/mfd/tps65910.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c index ca0b61011def..6e105cca27d4 100644 --- a/drivers/mfd/tps65910.c +++ b/drivers/mfd/tps65910.c @@ -436,12 +436,18 @@ static void tps65910_power_off(void) tps65910 = dev_get_drvdata(&tps65910_i2c_client->dev); + /* + * The PWR_OFF bit needs to be set separately, before transitioning + * to the OFF state. It enables the "sequential" power-off mode on + * TPS65911, it's a NO-OP on TPS65910. + */ if (regmap_set_bits(tps65910->regmap, TPS65910_DEVCTRL, DEVCTRL_PWR_OFF_MASK) < 0) return; - regmap_clear_bits(tps65910->regmap, TPS65910_DEVCTRL, - DEVCTRL_DEV_ON_MASK); + regmap_update_bits(tps65910->regmap, TPS65910_DEVCTRL, + DEVCTRL_DEV_OFF_MASK | DEVCTRL_DEV_ON_MASK, + DEVCTRL_DEV_OFF_MASK); } static int tps65910_i2c_probe(struct i2c_client *i2c, -- 2.29.2