Messages in this thread | | | From | DLG Adam Thomson <> | Subject | RE: [PATCH v2 1/2] mfd: da9062: enable being a system-power-controller | Date | Tue, 26 Apr 2022 09:14:34 +0000 |
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On 22 April 2022 07:17, Helmut Grohne wrote:
> The DA9062 can be the device used to power the CPU. In that case, it can > be used to power off the system. In the CONTROL_A register, the M_*_EN > bits must be zero for the corresponding *_EN bits to have an effect. We > zero them all to turn off the system. > > Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de> > --- > drivers/mfd/da9062-core.c | 31 +++++++++++++++++++++++++++++++ > 1 file changed, 31 insertions(+) > > This series effectively is a rebased resend. The earlier posting was > https://lore.kernel.org/all/20200107120559.GA700@laureti-dev/. At that time, > Adam Thomson critisized the use of regmap and i2c inside a pm_power_off hook > since irqs are disabled. He reached out to Lee Jones, who asked Mark Brown and > Wolfram Sang, but never got any reply. I noted that a fair number of other > drivers do use regmap and i2c despite this issue. In the mean time, more > instances were added: > * drivers/mfd/acer-ec-a500.c uses i2c > * drivers/mfd/ntxec.c uses i2c > * drivers/mfd/rk808.c uses regmap and i2c > Given that we proceeded with accepting the use of i2c and regmap inside > pm_power_off hooks, I think we can proceed with this patch as well. > > Helmut
I still have concerns, but maybe it's up to the integrator of a platform to determine if this approach for poweroff is valid and usable, although I still think it would be good to have checks somewhere as to whether a platform can actually perform atmoic I2C access when IRQs are disabled. However, without further insight right now:
Reviewed-by: Adam Thomson <DLG-Adam.Thomson.Opensource@dm.renesas.com>
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