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| author |   Geert Uytterhoeven <geert+renesas@glider.be> | 2019-06-24 14:35:40 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-03 19:31:30 +0200 |
| commit | 775b7ffd7d6d5db320d99b0a485c51e04dfcf9f1 (patch) | |
| tree | 91670d866a6c7e877d97c5a08df774f005b901f1 /drivers/tty | |
| parent | serial: sh-sci: Fix TX DMA buffer flushing and workqueue races (diff) | |
| download | linux-dev-775b7ffd7d6d5db320d99b0a485c51e04dfcf9f1.tar.xz linux-dev-775b7ffd7d6d5db320d99b0a485c51e04dfcf9f1.zip | |
serial: sh-sci: Terminate TX DMA during buffer flushing
While the .flush_buffer() callback clears sci_port.tx_dma_len since
commit 1cf4a7efdc71cab8 ("serial: sh-sci: Fix race condition causing
garbage during shutdown"), it does not terminate a transmit DMA
operation that may be in progress.
Fix this by terminating any pending DMA operations, and resetting the
corresponding cookie.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Link: https://lore.kernel.org/r/20190624123540.20629-3-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/sh-sci.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index d4504daff992..d18c680aa64b 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1656,11 +1656,18 @@ static void sci_free_dma(struct uart_port *port) static void sci_flush_buffer(struct uart_port *port) { + struct sci_port *s = to_sci_port(port); + /* * In uart_flush_buffer(), the xmit circular buffer has just been - * cleared, so we have to reset tx_dma_len accordingly. + * cleared, so we have to reset tx_dma_len accordingly, and stop any + * pending transfers */ - to_sci_port(port)->tx_dma_len = 0; + s->tx_dma_len = 0; + if (s->chan_tx) { + dmaengine_terminate_async(s->chan_tx); + s->cookie_tx = -EINVAL; + } } #else /* !CONFIG_SERIAL_SH_SCI_DMA */ static inline void sci_request_dma(struct uart_port *port) |