From: Douglas Anderson <diand...@chromium.org>
Date: Fri, May 10, 2019 at 3:35 PM
To: Mark Brown, Benson Leung, Enric Balletbo i Serra
Cc: <linux-rockc...@lists.infradead.org>, <drink...@chromium.org>,
Guenter Roeck, <briannor...@chromium.org>, <m...@chromium.org>, Douglas
Anderson, <linux-kernel@vger.kernel.org>, <linux-...@vger.kernel.org>
> If a controller specifies that it needs high priority for sending
> messages we should always schedule our transfers on the thread. If we
> don't do this we'll do the transfer in the caller's context which
> might not be very high priority.
>
> Signed-off-by: Douglas Anderson <diand...@chromium.org>
Reviewed-by: Guenter Roeck <gro...@chromium.org>
> ---
>
> drivers/spi/spi.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
> index 8eb7460dd744..0597f7086de3 100644
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -1230,8 +1230,11 @@ static void __spi_pump_messages(struct spi_controller
> *ctlr, bool in_kthread)
> return;
> }
>
> - /* If another context is idling the device then defer */
> - if (ctlr->idling) {
> + /*
> + * If another context is idling the device then defer.
> + * If we are high priority then the thread should do the transfer.
> + */
> + if (ctlr->idling || (ctlr->rt && !in_kthread)) {
> kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages);
> spin_unlock_irqrestore(&ctlr->queue_lock, flags);
> return;
> --
> 2.21.0.1020.gf2820cf01a-goog
>
