From 39fe33f98b64501f5816f743c052215e7f66700b Mon Sep 17 00:00:00 2001 From: Ben Whitten Date: Mon, 14 Nov 2016 15:13:20 +0000 Subject: spi: atmel: Fix scheduling while atomic A call to clk_get_rate appears to be called in the context of an interrupt, cache the bus clock for the frequency calculations in transmission. This fixes a 'BUG: scheduling while atomic' and 'WARNING: CPU: 0 PID: 777 at kernel/sched/core.c:2960 atmel_spi_unlock' Signed-off-by: Ben Whitten Signed-off-by: Steve deRosier Acked-by: Nicolas Ferre Acked-by: Alexandre Belloni Signed-off-by: Mark Brown --- drivers/spi/spi-atmel.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index d3affa6afe7e..9fb00ac3ac2e 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -296,6 +296,7 @@ struct atmel_spi { int irq; struct clk *clk; struct platform_device *pdev; + unsigned long spi_clk; struct spi_transfer *current_transfer; int current_remaining_bytes; @@ -865,7 +866,7 @@ static int atmel_spi_set_xfer_speed(struct atmel_spi *as, unsigned long bus_hz; /* v1 chips start out at half the peripheral bus speed. */ - bus_hz = clk_get_rate(as->clk); + bus_hz = as->spi_clk; if (!atmel_spi_is_v2(as)) bus_hz /= 2; @@ -1634,6 +1635,9 @@ static int atmel_spi_probe(struct platform_device *pdev) ret = clk_prepare_enable(clk); if (ret) goto out_free_irq; + + as->spi_clk = clk_get_rate(clk); + spi_writel(as, CR, SPI_BIT(SWRST)); spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */ if (as->caps.has_wdrbt) { -- cgit v1.2.3