summaryrefslogtreecommitdiffstats
path: root/drivers/serial/atmel_serial.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/serial/atmel_serial.c')
-rw-r--r--drivers/serial/atmel_serial.c30
1 files changed, 21 insertions, 9 deletions
diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c
index d57bf3e708d8..430997e33fc4 100644
--- a/drivers/serial/atmel_serial.c
+++ b/drivers/serial/atmel_serial.c
@@ -96,6 +96,7 @@
/* PDC registers */
#define UART_PUT_PTCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
+#define UART_GET_TCR(port) __raw_readl((port)->membase + ATMEL_PDC_TCR)
#define UART_GET_PTSR(port) __raw_readl((port)->membase + ATMEL_PDC_PTSR)
#define UART_PUT_RPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_RPR)
@@ -106,6 +107,7 @@
#define UART_PUT_TPR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TPR)
#define UART_PUT_TCR(port,v) __raw_writel(v, (port)->membase + ATMEL_PDC_TCR)
+#define UART_GET_TCR(port) __raw_readl((port)->membase + ATMEL_PDC_TCR)
static int (*atmel_open_hook)(struct uart_port *);
static void (*atmel_close_hook)(struct uart_port *);
@@ -562,17 +564,22 @@ static void atmel_tx_dma(struct uart_port *port)
struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
int count;
+ /* nothing left to transmit? */
+ if (UART_GET_TCR(port))
+ return;
+
xmit->tail += pdc->ofs;
xmit->tail &= UART_XMIT_SIZE - 1;
port->icount.tx += pdc->ofs;
pdc->ofs = 0;
- if (!uart_circ_empty(xmit)) {
- /* more to transmit - setup next transfer */
+ /* more to transmit - setup next transfer */
- /* disable PDC transmit */
- UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+ /* disable PDC transmit */
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+
+ if (!uart_circ_empty(xmit)) {
dma_sync_single_for_device(port->dev,
pdc->dma_addr,
pdc->dma_size,
@@ -586,11 +593,6 @@ static void atmel_tx_dma(struct uart_port *port)
/* re-enable PDC transmit and interrupts */
UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
UART_PUT_IER(port, ATMEL_US_ENDTX | ATMEL_US_TXBUFE);
- } else {
- /* nothing left to transmit - disable the transmitter */
-
- /* disable PDC transmit */
- UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
@@ -1274,6 +1276,7 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
{
struct uart_port *port = &atmel_ports[co->index].uart;
unsigned int status, imr;
+ unsigned int pdc_tx;
/*
* First, save IMR and then disable interrupts
@@ -1281,6 +1284,10 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
imr = UART_GET_IMR(port);
UART_PUT_IDR(port, ATMEL_US_RXRDY | ATMEL_US_TXRDY);
+ /* Store PDC transmit status and disable it */
+ pdc_tx = UART_GET_PTSR(port) & ATMEL_PDC_TXTEN;
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
+
uart_console_write(port, s, count, atmel_console_putchar);
/*
@@ -1290,6 +1297,11 @@ static void atmel_console_write(struct console *co, const char *s, u_int count)
do {
status = UART_GET_CSR(port);
} while (!(status & ATMEL_US_TXRDY));
+
+ /* Restore PDC transmit status */
+ if (pdc_tx)
+ UART_PUT_PTCR(port, ATMEL_PDC_TXTEN);
+
/* set interrupts back the way they were */
UART_PUT_IER(port, imr);
}