diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 4d277804c63e..3524ed2c0c73 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -214,14 +214,11 @@ static void stm32_usart_receive_chars(struct uart_port *port, bool threaded) struct tty_port *tport = &port->state->port; struct stm32_port *stm32_port = to_stm32_port(port); const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs; - unsigned long c, flags; + unsigned long c; u32 sr; char flag; - if (threaded) - spin_lock_irqsave(&port->lock, flags); - else - spin_lock(&port->lock); + spin_lock(&port->lock); while (stm32_usart_pending_rx(port, &sr, &stm32_port->last_res, threaded)) { @@ -278,10 +275,7 @@ static void stm32_usart_receive_chars(struct uart_port *port, bool threaded) uart_insert_char(port, sr, USART_SR_ORE, c, flag); } - if (threaded) - spin_unlock_irqrestore(&port->lock, flags); - else - spin_unlock(&port->lock); + spin_unlock(&port->lock); tty_flip_buffer_push(tport); } @@ -667,7 +661,8 @@ static int stm32_usart_startup(struct uart_port *port) ret = request_threaded_irq(port->irq, stm32_usart_interrupt, stm32_usart_threaded_interrupt, - IRQF_NO_SUSPEND, name, port); + IRQF_ONESHOT | IRQF_NO_SUSPEND, + name, port); if (ret) return ret; @@ -1156,6 +1151,13 @@ static int stm32_usart_of_dma_rx_probe(struct stm32_port *stm32port, struct dma_async_tx_descriptor *desc = NULL; int ret; + /* + * Using DMA and threaded handler for the console could lead to + * deadlocks. + */ + if (uart_console(port)) + return -ENODEV; + /* Request DMA RX channel */ stm32port->rx_ch = dma_request_slave_channel(dev, "rx"); if (!stm32port->rx_ch) {