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| author | Erwan Le Ray <erwan.leray@foss.st.com> | 2021-01-06 17:21:56 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-07 16:19:28 +0100 |
| commit | e7997f7ff7f8154d477f6f976698d868a2ac3934 (patch) | |
| tree | ea8d5a57942128c6e96b470f7b40ede61ab80b7e /drivers/tty | |
| parent | c762a2b846b619c0f92f23e2e8e16f70d20df800 (diff) | |
| download | linux-stable-e7997f7ff7f8154d477f6f976698d868a2ac3934.tar.gz linux-stable-e7997f7ff7f8154d477f6f976698d868a2ac3934.tar.bz2 linux-stable-e7997f7ff7f8154d477f6f976698d868a2ac3934.zip | |
serial: stm32: fix DMA initialization error handling
DMA initialization error handling is not properly implemented in the
driver.
Fix DMA initialization error handling by:
- moving TX DMA descriptor request error handling in a new dedicated
fallback_err label
- adding error handling to TX DMA descriptor submission
- adding error handling to RX DMA descriptor submission
This patch depends on '24832ca3ee85 ("tty: serial: stm32-usart: Remove set
but unused 'cookie' variables")' which unfortunately doesn't include a
"Fixes" tag.
Fixes: 3489187204eb ("serial: stm32: adding dma support")
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Link: https://lore.kernel.org/r/20210106162203.28854-2-erwan.leray@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/stm32-usart.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index f4de32d3f2af..6248304a001f 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -383,17 +383,18 @@ static void stm32_transmit_chars_dma(struct uart_port *port) DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT); - if (!desc) { - for (i = count; i > 0; i--) - stm32_transmit_chars_pio(port); - return; - } + if (!desc) + goto fallback_err; desc->callback = stm32_tx_dma_complete; desc->callback_param = port; /* Push current DMA TX transaction in the pending queue */ - dmaengine_submit(desc); + if (dma_submit_error(dmaengine_submit(desc))) { + /* dma no yet started, safe to free resources */ + dmaengine_terminate_async(stm32port->tx_ch); + goto fallback_err; + } /* Issue pending DMA TX requests */ dma_async_issue_pending(stm32port->tx_ch); @@ -402,6 +403,11 @@ static void stm32_transmit_chars_dma(struct uart_port *port) xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); port->icount.tx += count; + return; + +fallback_err: + for (i = count; i > 0; i--) + stm32_transmit_chars_pio(port); } static void stm32_transmit_chars(struct uart_port *port) @@ -1130,7 +1136,11 @@ static int stm32_of_dma_rx_probe(struct stm32_port *stm32port, desc->callback_param = NULL; /* Push current DMA transaction in the pending queue */ - dmaengine_submit(desc); + ret = dma_submit_error(dmaengine_submit(desc)); + if (ret) { + dmaengine_terminate_sync(stm32port->rx_ch); + goto config_err; + } /* Issue pending DMA requests */ dma_async_issue_pending(stm32port->rx_ch); |