Merge remote-tracking branch 'spi/topic/pump-rt' into spi-next (26ac5650) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/spi/spi.c

+30 −6

Original line number	Diff line number	Diff line
		@@ -1417,10 +1417,32 @@ static void spi_pump_messages(struct kthread_work *work)
		__spi_pump_messages(ctlr, true);
		}

		static int spi_init_queue(struct spi_controller *ctlr)
		/**
		* spi_set_thread_rt - set the controller to pump at realtime priority
		* @ctlr: controller to boost priority of
		*
		* This can be called because the controller requested realtime priority
		* (by setting the ->rt value before calling spi_register_controller()) or
		* because a device on the bus said that its transfers needed realtime
		* priority.
		*
		* NOTE: at the moment if any device on a bus says it needs realtime then
		* the thread will be at realtime priority for all transfers on that
		* controller. If this eventually becomes a problem we may see if we can
		* find a way to boost the priority only temporarily during relevant
		* transfers.
		*/
		static void spi_set_thread_rt(struct spi_controller *ctlr)
		{
		struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };

		dev_info(&ctlr->dev,
		"will run message pump with realtime priority\n");
		sched_setscheduler(ctlr->kworker_task, SCHED_FIFO, &param);
		}

		static int spi_init_queue(struct spi_controller *ctlr)
		{
		ctlr->running = false;
		ctlr->busy = false;

		@@ -1440,11 +1462,8 @@ static int spi_init_queue(struct spi_controller *ctlr)
		* request and the scheduling of the message pump thread. Without this
		* setting the message pump thread will remain at default priority.
		*/
		if (ctlr->rt) {
		dev_info(&ctlr->dev,
		"will run message pump with realtime priority\n");
		sched_setscheduler(ctlr->kworker_task, SCHED_FIFO, &param);
		}
		if (ctlr->rt)
		spi_set_thread_rt(ctlr);

		return 0;
		}
		@@ -3071,6 +3090,11 @@ int spi_setup(struct spi_device *spi)

		spi_set_cs(spi, false);

		if (spi->rt && !spi->controller->rt) {
		spi->controller->rt = true;
		spi_set_thread_rt(spi->controller);
		}

		dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n",
		(int) (spi->mode & (SPI_CPOL \| SPI_CPHA)),
		(spi->mode & SPI_CS_HIGH) ? "cs_high, " : "",

include/linux/spi/spi.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -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 */