spi: bcm2835: Tear down DMA before turning off SPI controller

On unbind of the BCM2835 SPI driver, the SPI controller is disabled
first and the DMA channels are terminated and torn down afterwards.

This seems backwards:  In the theoretical case that DMA is active,
it might try to fill the SPI FIFOs even after the controller has
been disabled.

Reverse the order, thereby mirroring what's done on ->probe().

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/ac79f1e3d6fd9a1f5e0cb4008c43b98ea70be3c2.1589557526.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index 06d2782d38ece9079224e9bded2dac9d57c85669..20d8581fdf887373f4d07e1d6d1eb1625c70d5be 100644 (file)
--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -1380,14 +1380,14 @@ static int bcm2835_spi_remove(struct platform_device *pdev)
 
        spi_unregister_controller(ctlr);
 
+       bcm2835_dma_release(ctlr, bs);
+
        /* Clear FIFOs, and disable the HW block */
        bcm2835_wr(bs, BCM2835_SPI_CS,
                   BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX);
 
        clk_disable_unprepare(bs->clk);
 
-       bcm2835_dma_release(ctlr, bs);
-
        return 0;
 }