diff options
Diffstat (limited to 'drivers/tty/serial/stm32-usart.c')
| -rw-r--r-- | drivers/tty/serial/stm32-usart.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 1e24bee2b0ef..a1490033aa16 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -797,9 +797,23 @@ static irqreturn_t stm32_usart_interrupt(int irq, void *ptr) spin_unlock(&port->lock); } + if (stm32_usart_rx_dma_enabled(port)) + return IRQ_WAKE_THREAD; + else + return IRQ_HANDLED; +} + +static irqreturn_t stm32_usart_threaded_interrupt(int irq, void *ptr) +{ + struct uart_port *port = ptr; + struct tty_port *tport = &port->state->port; + struct stm32_port *stm32_port = to_stm32_port(port); + unsigned int size; + unsigned long flags; + /* Receiver timeout irq for DMA RX */ - if (stm32_usart_rx_dma_enabled(port) && !stm32_port->throttled) { - spin_lock(&port->lock); + if (!stm32_port->throttled) { + spin_lock_irqsave(&port->lock, flags); size = stm32_usart_receive_chars(port, false); uart_unlock_and_check_sysrq_irqrestore(port, flags); if (size) @@ -1001,8 +1015,10 @@ static int stm32_usart_startup(struct uart_port *port) u32 val; int ret; - ret = request_irq(port->irq, stm32_usart_interrupt, - IRQF_NO_SUSPEND, name, port); + ret = request_threaded_irq(port->irq, stm32_usart_interrupt, + stm32_usart_threaded_interrupt, + IRQF_ONESHOT | IRQF_NO_SUSPEND, + name, port); if (ret) return ret; @@ -1585,6 +1601,13 @@ static int stm32_usart_of_dma_rx_probe(struct stm32_port *stm32port, struct dma_slave_config config; int ret; + /* + * Using DMA and threaded handler for the console could lead to + * deadlocks. + */ + if (uart_console(port)) + return -ENODEV; + stm32port->rx_buf = dma_alloc_coherent(dev, RX_BUF_L, &stm32port->rx_dma_buf, GFP_KERNEL); |