4.20-stable review patch. If anyone has any objections, please let me know.
------------------ From: Lukas Wunner <[email protected]> commit dbc944115eed48af110646992893dc43321368d8 upstream. If submission of a DMA TX transfer succeeds but submission of the corresponding RX transfer does not, the BCM2835 SPI driver terminates the TX transfer but neglects to reset the dma_pending flag to false. Thus, if the next transfer uses interrupt mode (because it is shorter than BCM2835_SPI_DMA_MIN_LENGTH) and runs into a timeout, dmaengine_terminate_all() will be called both for TX (once more) and for RX (which was never started in the first place). Fix it. Signed-off-by: Lukas Wunner <[email protected]> Fixes: 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers meeting certain conditions") Cc: [email protected] # v4.2+ Cc: Mathias Duckeck <[email protected]> Cc: Frank Pavlic <[email protected]> Cc: Martin Sperl <[email protected]> Cc: Noralf Trønnes <[email protected]> Signed-off-by: Mark Brown <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/spi/spi-bcm2835.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -341,6 +341,7 @@ static int bcm2835_spi_transfer_one_dma( if (ret) { /* need to reset on errors */ dmaengine_terminate_all(master->dma_tx); + bs->dma_pending = false; bcm2835_spi_reset_hw(master); return ret; }
