Re: [PATCH 1/4] can: mcp251xfd: stop timestamp before sending chip to sleep

Marc Kleine-Budde
2024-04-25T06:29:39Z

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On 25.04.2024 07:17:11, Gregor Herburger wrote:
> On Wed, Apr 24, 2024 at 01:54:54PM +0200, Marc Kleine-Budde wrote:
> > On 17.04.2024 15:43:54, Gregor Herburger wrote:
> > > MCP2518FD exits Low-Power Mode (LPM) when CS is asserted. When chip
> > > is send to sleep and the timestamp workqueue is not stopped chip is
> > > waked by SPI transfer of mcp251xfd_timestamp_read.
> >
> > How does the Low-Power Mode affect the GPIO lines? Is there a difference
> > if the device is only in sleep mode?
>
> The MCP251XFD_REG_IOCON is cleared when leaving Low-Power Mode. This is
> why I implemented regcache.

But that means you have to power the chip if a GPIO is requested. You
have to power up the chip in the request() callback and power it down in
the free() callback.

I've 2 patches laying around, one that moves the timestamp
init/start/stop into the chip_start/stop. And another one that moves the
soft reset and basic configuration of the chip into the runtime pm
functions. I have to make both patches compatible and send them to the
list. Feel free to pick them up and integrate them into your series.

regards,
Marc

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