Messages in this thread | | | Date | Mon, 2 Nov 2020 18:16:55 +0000 | From | Mark Brown <> | Subject | Re: [PATCH] spi: add runtime PM for transfer_one_message |
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On Mon, Nov 02, 2020 at 07:22:39PM +0800, Chunyan Zhang wrote: > From: Chunyan Zhang <chunyan.zhang@unisoc.com>
> Before transfer message, spi devices probably have been in runtime suspended, > that would cause the kernel crash on some platforms once access spi > registers, such as on Unisoc's SoCs. The spi devices can be suspended > until message transfer completed.
This commit message is a bit hard to follow so I don't really understand what the issue is. We only ever call transfer_one_message() from within __spi_pump_messages() which already handles auto_runtime_pm so I'm not seeing the situation where we might get to transfer_one_message() without having already runtime resumed the controller. What exactly is the error situation here? This code has been around for a while and I'm not aware of reports of issues here and I can't see anything unusual that the Spreadtrum driver is doing.
Also why are we doing this in transfer_one_message() where it will only work for controllers using that? If we're missing runtime PM in some paths then presumably controllers with a custom implementation are also going to be affected as well, auto_runtime_pm is supposed to work for them as well. [unhandled content-type:application/pgp-signature] | |