From: Valentin Caron valentin.caron@foss.st.com
[ Upstream commit 56a23f9319e86e1d62a109896e2c7e52c414e67d ]
Terminate DMA transaction and clear CR3_DMAT when shutdown is requested, instead of when remove is requested. If DMA transfer is not stopped in shutdown ops, driver will fail to start a new DMA transfer after next startup ops.
Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray erwan.leray@foss.st.com Signed-off-by: Valentin Caron valentin.caron@foss.st.com Link: https://lore.kernel.org/r/20220104182445.4195-2-valentin.caron@foss.st.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/stm32-usart.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 3244e7f6818ca..6cfc3bec67492 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -883,6 +883,11 @@ static void stm32_usart_shutdown(struct uart_port *port) u32 val, isr; int ret;
+ if (stm32_port->tx_dma_busy) { + dmaengine_terminate_async(stm32_port->tx_ch); + stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAT); + } + /* Disable modem control interrupts */ stm32_usart_disable_ms(port);
@@ -1570,7 +1575,6 @@ static int stm32_usart_serial_remove(struct platform_device *pdev) writel_relaxed(cr3, port->membase + ofs->cr3);
if (stm32_port->tx_ch) { - dmaengine_terminate_async(stm32_port->tx_ch); stm32_usart_of_dma_tx_remove(stm32_port, pdev); dma_release_channel(stm32_port->tx_ch); }