Commit 1569039d authored by Hao Liang's avatar Hao Liang Committed by Greg Kroah-Hartman
Browse files

bfin uart: it will hang when read current y count if not disable dma irq 



Add irq disable and enable in bfin_serial_rx_dma_timeout in case of
system hang.

This reverts part of commit 9642dbe7 ("serial: bfin-uart: avoid
dead lock in rx irq handler in smp kernel").

Signed-off-by: default avatarHao Liang <hliang1025@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent da29169e

drivers/tty/serial/bfin_uart.c

+2 −0
Original line number Diff line number Diff line
@@ -464,6 +464,7 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart) 
	int x_pos, pos;

	unsigned long flags;



	dma_disable_irq_nosync(uart->rx_dma_channel);

	spin_lock_irqsave(&uart->rx_lock, flags);



	/* 2D DMA RX buffer ring is used. Because curr_y_count and
@@ -496,6 +497,7 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart) 
	}



	spin_unlock_irqrestore(&uart->rx_lock, flags);

	dma_enable_irq(uart->rx_dma_channel);



	mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);

}

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