| Message ID | 20200524192643.18207-1-digetx@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] mfd: tps65910: Correct power-off programming sequence | expand |
On Sun, 24 May 2020, Dmitry Osipenko wrote: > 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@yahoo.com> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > > Changelog: > > v2: - Now using a single tps65910_reg_update_bits() instead of set+clear. > Thanks to Michał Mirosław for the suggestion. Michał should review. > drivers/mfd/tps65910.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c > index 11959021b50a..3f4483dec871 100644 > --- a/drivers/mfd/tps65910.c > +++ b/drivers/mfd/tps65910.c > @@ -440,8 +440,13 @@ 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; > + > + tps65910_reg_update_bits(tps65910, TPS65910_DEVCTRL, > + DEVCTRL_DEV_OFF_MASK | DEVCTRL_DEV_ON_MASK, > + DEVCTRL_DEV_OFF_MASK); > } > > static int tps65910_i2c_probe(struct i2c_client *i2c,
On Sun, May 24, 2020 at 10:26:43PM +0300, Dmitry Osipenko wrote: > 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. The datasheets of 65910 and 65911 say that ON and SLP bits are cleared during OFF state. But I guess the hardware might work differently. [...] > --- a/drivers/mfd/tps65910.c > +++ b/drivers/mfd/tps65910.c > @@ -440,8 +440,13 @@ 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; > + > + tps65910_reg_update_bits(tps65910, TPS65910_DEVCTRL, > + DEVCTRL_DEV_OFF_MASK | DEVCTRL_DEV_ON_MASK, > + DEVCTRL_DEV_OFF_MASK); > } There is tps65910_reg_set_bits() at the start of function. I guess it doesn't work if your changes are needed. Maybe you can remove it? I would also include your observations about the chip's behaviour in the commit message so it doesn't get "fixed" later. Best Regards, Michał Mirosław
26.05.2020 18:01, Michał Mirosław пишет: > On Sun, May 24, 2020 at 10:26:43PM +0300, Dmitry Osipenko wrote: >> 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. > > The datasheets of 65910 and 65911 say that ON and SLP bits are cleared > during OFF state. But I guess the hardware might work differently. Indeed, sounds like we can remove the SLP bit-clearing safely. IIUC, both tps65910 and tps65911 are nearly the same in regards to the power-off programming, tps65911 only supports an additional (sequential) power-off mode. I'm not sure whether we've tried to remove the SLP bit-clearing before, will be interesting to try. > [...] >> --- a/drivers/mfd/tps65910.c >> +++ b/drivers/mfd/tps65910.c >> @@ -440,8 +440,13 @@ 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; >> + >> + tps65910_reg_update_bits(tps65910, TPS65910_DEVCTRL, >> + DEVCTRL_DEV_OFF_MASK | DEVCTRL_DEV_ON_MASK, >> + DEVCTRL_DEV_OFF_MASK); >> } > > There is tps65910_reg_set_bits() at the start of function. I guess it > doesn't work if your changes are needed. Maybe you can remove it? It enables the "sequential power-off, reverse of power-on sequence", like datasheet says. I think it works and we actually need that PWR_OFF bit to be set separately, before setting the DEV_OFF bit. > I would also include your observations about the chip's behaviour in the > commit message so it doesn't get "fixed" later. I'll add a clarifying comment about it in v3, thank you for the suggestions.
diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c index 11959021b50a..3f4483dec871 100644 --- a/drivers/mfd/tps65910.c +++ b/drivers/mfd/tps65910.c @@ -440,8 +440,13 @@ 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; + + tps65910_reg_update_bits(tps65910, TPS65910_DEVCTRL, + DEVCTRL_DEV_OFF_MASK | DEVCTRL_DEV_ON_MASK, + DEVCTRL_DEV_OFF_MASK); } static int tps65910_i2c_probe(struct i2c_client *i2c,