From 924b5867e7bd6a6a98014f0517b747465b108011 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Wed, 15 May 2019 09:48:12 -0700 Subject: spi: Allow SPI devices to request the pumping thread be realtime Right now the only way to get the SPI pumping thread bumped up to realtime priority is for the controller to request it. However it may be that the controller works fine with the normal priority but communication to a particular SPI device on the bus needs realtime priority. Let's add a way for devices to request realtime priority when they set themselves up. NOTE: this will just affect the priority of transfers that end up on the SPI core's pumping thread. In many cases transfers happen in the context of the caller so if you need realtime priority for all transfers you should ensure the calling context is also realtime priority. Signed-off-by: Douglas Anderson Reviewed-by: Guenter Roeck Tested-by: Enric Balletbo i Serra Signed-off-by: Mark Brown --- include/linux/spi/spi.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 053abd22ad31..15505c2485d6 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -109,6 +109,7 @@ void spi_statistics_add_transfer_stats(struct spi_statistics *stats, * This may be changed by the device's driver, or left at the * default (0) indicating protocol words are eight bit bytes. * The spi_transfer.bits_per_word can override this for each transfer. + * @rt: Make the pump thread real time priority. * @irq: Negative, or the number passed to request_irq() to receive * interrupts from this device. * @controller_state: Controller's runtime state @@ -143,6 +144,7 @@ struct spi_device { u32 max_speed_hz; u8 chip_select; u8 bits_per_word; + bool rt; u32 mode; #define SPI_CPHA 0x01 /* clock phase */ #define SPI_CPOL 0x02 /* clock polarity */ -- cgit v1.2.3