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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Wed, 29 Nov 2023 14:58:10 +0100
Message-ID: <CACRpkdZmgiON1Sz3e0LobeyDCpiyX-TGswC4xQ62sWQcEi2bjA@mail.gmail.com>
Subject: Re: [PATCH 2/2] spi: spl022: switch to use default spi_transfer_one_message()
To:     Nam Cao <namcao@linutronix.de>
Cc:     broonie@kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org
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On Wed, Nov 29, 2023 at 2:32=E2=80=AFPM Nam Cao <namcao@linutronix.de> wrot=
e:

> Except for polling mode, this driver's transfer_one_message() makes use
> of interrupt handler and tasklet. This is problematic because
> spi_transfer_delay_exec(), who may sleep, is called in interrupt handler
> and tasklet. This causes the following warning:
> BUG: sleeping function called from invalid context at drivers/spi/spi.c:1=
428
>
> Switch to use the default spi_transfer_one_message() instead, which
> calls spi_transfer_delay_exec() appropriately.
>
> Signed-off-by: Nam Cao <namcao@linutronix.de>
> ---
> Tested with polling mode and interrupt mode, NOT with DMA mode.
> Support with testing very appreciated!

Oh this is great!

Because I think Mark started nagging me something like 10 years
ago to fix this in this driver...

I have a device using DMA mode, I will dig it out and make sure to
get this tested ASAP, in the meantime:

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij