From f960c6dafcb1998d5c2e2f2c1c88f6474fe0075e Mon Sep 17 00:00:00 2001 From: Yonghan Ye Date: Wed, 4 Dec 2019 20:00:07 +0800 Subject: [PATCH] serial: sprd: Add clearing break interrupt operation commit abeb2e9414d7e3a0d8417bc3b13d7172513ea8a0 upstream. A break interrupt will be generated if the RX line was pulled low, which means some abnomal behaviors occurred of the UART. In this case, we still need to clear this break interrupt status, otherwise it will cause irq storm to crash the whole system. Fixes: b7396a38fb28 ("tty/serial: Add Spreadtrum sc9836-uart driver support") Signed-off-by: Yonghan Ye Cc: stable Signed-off-by: Baolin Wang Link: https://lore.kernel.org/r/925e51b73099c90158e080b8f5bed9b3b38c4548.1575460601.git.baolin.wang7@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sprd_serial.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c index 771d11196523..494e2672ebd7 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -679,6 +679,9 @@ static irqreturn_t sprd_handle_irq(int irq, void *dev_id) if (ims & SPRD_IMSR_TIMEOUT) serial_out(port, SPRD_ICLR, SPRD_ICLR_TIMEOUT); + if (ims & SPRD_IMSR_BREAK_DETECT) + serial_out(port, SPRD_ICLR, SPRD_IMSR_BREAK_DETECT); + if (ims & (SPRD_IMSR_RX_FIFO_FULL | SPRD_IMSR_BREAK_DETECT | SPRD_IMSR_TIMEOUT)) sprd_rx(port);