From: Erwan Le Ray erwan.leray@foss.st.com
[ Upstream commit 87fd0741d6dcf63ebdb14050c2b921ae14c7f307 ]
The probe and remove orders are wrong as the uart_port is registered before saving device data in the probe, and unregistered after DMA resource deallocation in the remove. uart_port registering should be done at the end of probe and unregistering should be done at the begin of remove to avoid resource allocation issues.
Fix probe and remove orders. This enforce resource allocation occur at proper time. Terminate both DMA rx and tx transfers before removing device.
Move pm_runtime after uart_remove_one_port() call in remove() to keep the probe error path.
Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray erwan.leray@foss.st.com Link: https://lore.kernel.org/r/20210304162308.8984-2-erwan.leray@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 | 57 ++++++++++++++++++++++++-------- 1 file changed, 44 insertions(+), 13 deletions(-)
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index b3675cf25a69..3d58824ac2af 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -1252,10 +1252,6 @@ static int stm32_usart_serial_probe(struct platform_device *pdev) device_set_wakeup_enable(&pdev->dev, false); }
- ret = uart_add_one_port(&stm32_usart_driver, &stm32port->port); - if (ret) - goto err_wirq; - ret = stm32_usart_of_dma_rx_probe(stm32port, pdev); if (ret) dev_info(&pdev->dev, "interrupt mode used for rx (no dma)\n"); @@ -1269,11 +1265,40 @@ static int stm32_usart_serial_probe(struct platform_device *pdev) pm_runtime_get_noresume(&pdev->dev); pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); + + ret = uart_add_one_port(&stm32_usart_driver, &stm32port->port); + if (ret) + goto err_port; + pm_runtime_put_sync(&pdev->dev);
return 0;
-err_wirq: +err_port: + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); + + if (stm32port->rx_ch) { + dmaengine_terminate_async(stm32port->rx_ch); + dma_release_channel(stm32port->rx_ch); + } + + if (stm32port->rx_dma_buf) + dma_free_coherent(&pdev->dev, + RX_BUF_L, stm32port->rx_buf, + stm32port->rx_dma_buf); + + if (stm32port->tx_ch) { + dmaengine_terminate_async(stm32port->tx_ch); + dma_release_channel(stm32port->tx_ch); + } + + if (stm32port->tx_dma_buf) + dma_free_coherent(&pdev->dev, + TX_BUF_L, stm32port->tx_buf, + stm32port->tx_dma_buf); + if (stm32port->wakeirq > 0) dev_pm_clear_wake_irq(&pdev->dev);
@@ -1295,11 +1320,20 @@ static int stm32_usart_serial_remove(struct platform_device *pdev) int err;
pm_runtime_get_sync(&pdev->dev); + err = uart_remove_one_port(&stm32_usart_driver, port); + if (err) + return(err); + + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev);
stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAR);
- if (stm32_port->rx_ch) + if (stm32_port->rx_ch) { + dmaengine_terminate_async(stm32_port->rx_ch); dma_release_channel(stm32_port->rx_ch); + }
if (stm32_port->rx_dma_buf) dma_free_coherent(&pdev->dev, @@ -1308,8 +1342,10 @@ static int stm32_usart_serial_remove(struct platform_device *pdev)
stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAT);
- if (stm32_port->tx_ch) + if (stm32_port->tx_ch) { + dmaengine_terminate_async(stm32_port->tx_ch); dma_release_channel(stm32_port->tx_ch); + }
if (stm32_port->tx_dma_buf) dma_free_coherent(&pdev->dev, @@ -1323,12 +1359,7 @@ static int stm32_usart_serial_remove(struct platform_device *pdev)
stm32_usart_deinit_port(stm32_port);
- err = uart_remove_one_port(&stm32_usart_driver, port); - - pm_runtime_disable(&pdev->dev); - pm_runtime_put_noidle(&pdev->dev); - - return err; + return 0; }
#ifdef CONFIG_SERIAL_STM32_CONSOLE