Blackfin Serial Driver: Fix bug - update tx dma buffer tail before wake up processes.

Also make rx dma buffer work as a loop.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
This commit is contained in:
Sonic Zhang 2008-02-25 15:19:09 +08:00 committed by Bryan Wu
parent 0711d85760
commit 56f5de8fe7

View file

@ -415,7 +415,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
*/
bfin_serial_mctrl_check(uart);
spin_lock_irqsave(&uart->port.lock, flags);
uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
uart->tx_count = UART_XMIT_SIZE - xmit->tail;
@ -439,7 +438,6 @@ static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
ier |= ETBEI;
UART_PUT_IER(uart, ier);
#endif
spin_unlock_irqrestore(&uart->port.lock, flags);
}
static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
@ -450,7 +448,9 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
status = UART_GET_LSR(uart);
UART_CLEAR_LSR(uart);
uart->port.icount.rx += CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail, UART_XMIT_SIZE);;
uart->port.icount.rx +=
CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
UART_XMIT_SIZE);
if (status & BI) {
uart->port.icount.brk++;
@ -476,10 +476,12 @@ static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
else
flg = TTY_NORMAL;
for (i = uart->rx_dma_buf.head; i < uart->rx_dma_buf.tail; i++) {
if (uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
goto dma_ignore_char;
uart_insert_char(&uart->port, status, OE, uart->rx_dma_buf.buf[i], flg);
for (i = uart->rx_dma_buf.tail; i != uart->rx_dma_buf.head; i++) {
if (i >= UART_XMIT_SIZE)
i = 0;
if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
uart_insert_char(&uart->port, status, OE,
uart->rx_dma_buf.buf[i], flg);
}
dma_ignore_char:
@ -492,16 +494,20 @@ void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
int flags = 0;
spin_lock_irqsave(&uart->port.lock, flags);
x_pos = DMA_RX_XCOUNT - get_dma_curr_xcount(uart->rx_dma_channel);
uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
if (uart->rx_dma_nrows == DMA_RX_YCOUNT)
uart->rx_dma_nrows = 0;
x_pos = DMA_RX_XCOUNT - x_pos;
if (x_pos == DMA_RX_XCOUNT)
x_pos = 0;
pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
if (pos>uart->rx_dma_buf.tail) {
uart->rx_dma_buf.tail = pos;
if (pos != uart->rx_dma_buf.tail) {
uart->rx_dma_buf.head = pos;
bfin_serial_dma_rx_chars(uart);
uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
}
spin_unlock_irqrestore(&uart->port.lock, flags);
uart->rx_dma_timer.expires = jiffies + DMA_RX_FLUSH_JIFFIES;
@ -525,12 +531,12 @@ static irqreturn_t bfin_serial_dma_tx_int(int irq, void *dev_id)
ier &= ~ETBEI;
UART_PUT_IER(uart, ier);
#endif
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uart->port);
xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
uart->port.icount.tx += uart->tx_count;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&uart->port);
bfin_serial_dma_tx_chars(uart);
}
@ -542,15 +548,16 @@ static irqreturn_t bfin_serial_dma_rx_int(int irq, void *dev_id)
{
struct bfin_serial_port *uart = dev_id;
unsigned short irqstat;
int pos;
uart->rx_dma_nrows++;
uart->rx_dma_buf.tail = DMA_RX_XCOUNT * uart->rx_dma_nrows;
bfin_serial_dma_rx_chars(uart);
if (uart->rx_dma_nrows >= DMA_RX_YCOUNT) {
uart->rx_dma_nrows = 0;
uart->rx_dma_buf.tail = 0;
uart->rx_dma_nrows = DMA_RX_YCOUNT -
get_dma_curr_ycount(uart->rx_dma_channel);
pos = DMA_RX_XCOUNT * uart->rx_dma_nrows;
if (pos != uart->rx_dma_buf.tail) {
uart->rx_dma_buf.head = pos;
bfin_serial_dma_rx_chars(uart);
uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
}
uart->rx_dma_buf.head = uart->rx_dma_buf.tail;
spin_lock(&uart->port.lock);
irqstat = get_dma_curr_irqstat(uart->rx_dma_channel);