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 9642dbe73c ("serial: bfin-uart: avoid
dead lock in rx irq handler in smp kernel").

Signed-off-by: Hao Liang <hliang1025@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Hao Liang 2015-03-26 17:13:24 +08:00 коммит произвёл Greg Kroah-Hartman
Родитель da29169e76
Коммит 1569039db0
1 изменённых файлов: 2 добавлений и 0 удалений

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@ -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);
}