[PATCH 04/75] Blackfin Serial Driver: Fix bug - BF527-EZKIT unable to receive large files over UART in DMA mode

Alan Cox
2009-01-02T13:40:23Z

From: Sonic Zhang <sonic.zhang@analog.com>

Add spin_lock_irqsave() when receive and transfer data.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Alan Cox <alan@redhat.com>
---

drivers/serial/bfin_5xx.c | 11 ++++++++---
1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index 88449d3..1c85039 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -81,7 +81,9 @@ static void bfin_serial_reset_irda(struct uart_port *port);
static void bfin_serial_stop_tx(struct uart_port *port)
{
struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
+#ifdef CONFIG_SERIAL_BFIN_DMA
struct circ_buf *xmit = &uart->port.info->xmit;
+#endif

while (!(UART_GET_LSR(uart) & TEMT))
cpu_relax();
@@ -412,7 +414,9 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)

void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
{
- int x_pos, pos;
+ int x_pos, pos, flags;
+
+ spin_lock_irqsave(&uart->port.lock, flags);

uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
@@ -430,6 +434,8 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
}

+ spin_unlock_irqrestore(&uart->port.lock, flags);
+
mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
}

@@ -464,10 +470,9 @@ static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
spin_lock(&uart->port.lock);
irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);
clear_dma_irqstat(uart->rx_dma_channel);
+ bfin_serial_dma_rx_chars(uart);
spin_unlock(&uart->port.lock);

- mod_timer(&(uart->rx_dma_timer), jiffies);
-
return IRQ_HANDLED;
}
#endif