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author | Marek Vasut <marex@denx.de> | 2023-01-12 19:04:17 +0100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-24 07:24:33 +0100 |
commit | 2b5412ca6fd33523a138131abdd8ddf873af913e (patch) | |
tree | 79fc3f0b9a64a05c63553a8f2fe777439f90df2d /drivers/tty | |
parent | 48b94e49980b088881029ee1c4bb01851bb7ff0c (diff) | |
download | linux-2b5412ca6fd33523a138131abdd8ddf873af913e.tar.gz |
serial: stm32: Merge hard IRQ and threaded IRQ handling into single IRQ handler
commit f24771b62a83239f0dce816bddf0f6807f436235 upstream. Requesting an interrupt with IRQF_ONESHOT will run the primary handler in the hard-IRQ context even in the force-threaded mode. The force-threaded mode is used by PREEMPT_RT in order to avoid acquiring sleeping locks (spinlock_t) in hard-IRQ context. This combination makes it impossible and leads to "sleeping while atomic" warnings. Use one interrupt handler for both handlers (primary and secondary) and drop the IRQF_ONESHOT flag which is not needed. Fixes: e359b4411c283 ("serial: stm32: fix threaded interrupt handling") Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Valentin Caron <valentin.caron@foss.st.com> # V3 Signed-off-by: Marek Vasut <marex@denx.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230112180417.25595-1-marex@denx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r-- | drivers/tty/serial/stm32-usart.c | 31 |
1 files changed, 4 insertions, 27 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index b8aed28b8f17..c28e2f10fb02 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -798,23 +798,9 @@ 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_port->throttled) { - spin_lock_irqsave(&port->lock, flags); + if (stm32_usart_rx_dma_enabled(port) && !stm32_port->throttled) { + spin_lock(&port->lock); size = stm32_usart_receive_chars(port, false); uart_unlock_and_check_sysrq_irqrestore(port, flags); if (size) @@ -1016,10 +1002,8 @@ static int stm32_usart_startup(struct uart_port *port) u32 val; int ret; - ret = request_threaded_irq(port->irq, stm32_usart_interrupt, - stm32_usart_threaded_interrupt, - IRQF_ONESHOT | IRQF_NO_SUSPEND, - name, port); + ret = request_irq(port->irq, stm32_usart_interrupt, + IRQF_NO_SUSPEND, name, port); if (ret) return ret; @@ -1602,13 +1586,6 @@ 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); |