Commit bfde9f19 authored Dec 15, 2017 by Radu Pirea Committed by Greg Kroah-Hartman Mar 03, 2018

spi: atmel: fixed spin_lock usage inside atmel_spi_remove




[ Upstream commit 66e900a3d225575c8b48b59ae1fe74bb6e5a65cc ]

The only part of atmel_spi_remove which needs to be atomic is hardware
reset.

atmel_spi_stop_dma calls dma_terminate_all and this needs interrupts
enabled.
atmel_spi_release_dma calls dma_release_channel and dma_release_channel
locks a mutex inside of spin_lock.

So the call of these functions can't be inside a spin_lock.

Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Radu Pirea <radu.pirea@microchip.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 7c7e39f7

drivers/spi/spi-atmel.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1416,12 +1416,12 @@ static int atmel_spi_remove(struct platform_device *pdev)
		struct atmel_spi *as = spi_master_get_devdata(master);

		/* reset the hardware and block queue progress */
		spin_lock_irq(&as->lock);
		if (as->use_dma) {
		atmel_spi_stop_dma(as);
		atmel_spi_release_dma(as);
		}

		spin_lock_irq(&as->lock);
		spi_writel(as, CR, SPI_BIT(SWRST));
		spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
		spi_readl(as, SR);