• Lukas Wunner's avatar
    spi: bcm2835: Fix book-keeping of DMA termination · fef1fb1f
    Lukas Wunner authored
    commit dbc94411 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: default avatarLukas Wunner <lukas@wunner.de>
    Fixes: 3ecd37ed ("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 Trønnes <noralf@tronnes.org>
    Signed-off-by: default avatarMark Brown <broonie@kernel.org>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    fef1fb1f
spi-bcm2835.c 23 KB