| From dbc944115eed48af110646992893dc43321368d8 Mon Sep 17 00:00:00 2001 |
| From: Lukas Wunner <lukas@wunner.de> |
| Date: Thu, 8 Nov 2018 08:06:10 +0100 |
| Subject: spi: bcm2835: Fix book-keeping of DMA termination |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Lukas Wunner <lukas@wunner.de> |
| |
| 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 <lukas@wunner.de> |
| Fixes: 3ecd37edaa2a ("spi: bcm2835: enable dma modes for transfers meeting certain conditions") |
| Cc: stable@vger.kernel.org # v4.2+ |
| Cc: Mathias Duckeck <m.duckeck@kunbus.de> |
| Cc: Frank Pavlic <f.pavlic@kunbus.de> |
| Cc: Martin Sperl <kernel@martin.sperl.org> |
| Cc: Noralf TrΓΈnnes <noralf@tronnes.org> |
| Signed-off-by: Mark Brown <broonie@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| 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; |
| } |
