[PATCH 2/6] Serial: AT91: Distinguish PDC from DMA
Elen Song
elen.song at atmel.com
Mon Oct 29 05:09:52 EDT 2012
Signed-off-by: Elen Song <elen.song at atmel.com>
---
drivers/tty/serial/atmel_serial.c | 74 ++++++++++++++++++++++---------------
1 file changed, 45 insertions(+), 29 deletions(-)
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 1b1bd4f..8a4b8f8 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -142,11 +142,13 @@ struct atmel_uart_port {
u32 backup_imr; /* IMR saved during suspend */
int break_active; /* break being received */
- short use_dma_rx; /* enable PDC receiver */
+ short use_dma_rx; /* enable DMA receiver */
+ short use_pdc_rx; /* enable PDC receiver */
short pdc_rx_idx; /* current PDC RX buffer */
struct atmel_dma_buffer pdc_rx[2]; /* PDC receier */
- short use_dma_tx; /* enable PDC transmitter */
+ short use_dma_tx; /* enable DMA transmitter */
+ short use_pdc_tx; /* enable PDC transmitter */
struct atmel_dma_buffer pdc_tx; /* PDC transmitter */
struct tasklet_struct tasklet;
@@ -183,31 +185,45 @@ to_atmel_uart_port(struct uart_port *uart)
}
#ifdef CONFIG_SERIAL_ATMEL_PDC
-static bool atmel_use_dma_rx(struct uart_port *port)
+static bool atmel_use_pdc_rx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- return atmel_port->use_dma_rx;
+ return atmel_port->use_pdc_rx;
}
-static bool atmel_use_dma_tx(struct uart_port *port)
+static bool atmel_use_pdc_tx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- return atmel_port->use_dma_tx;
+ return atmel_port->use_pdc_tx;
}
#else
-static bool atmel_use_dma_rx(struct uart_port *port)
+static bool atmel_use_pdc_rx(struct uart_port *port)
{
return false;
}
-static bool atmel_use_dma_tx(struct uart_port *port)
+static bool atmel_use_pdc_tx(struct uart_port *port)
{
return false;
}
#endif
+static bool atmel_use_dma_tx(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ return atmel_port->use_dma_tx;
+}
+
+static bool atmel_use_dma_rx(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+ return atmel_port->use_dma_rx;
+}
+
/* Enable or disable the rs485 support */
void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
{
@@ -235,7 +251,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
mode |= ATMEL_US_USMODE_RS485;
} else {
dev_dbg(port->dev, "Setting UART to RS232\n");
- if (atmel_use_dma_tx(port))
+ if (atmel_use_pdc_tx(port))
atmel_port->tx_done_mask = ATMEL_US_ENDTX |
ATMEL_US_TXBUFE;
else
@@ -347,7 +363,7 @@ static void atmel_stop_tx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (atmel_use_dma_tx(port)) {
+ if (atmel_use_pdc_tx(port)) {
/* disable PDC transmit */
UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
}
@@ -366,7 +382,7 @@ static void atmel_start_tx(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (atmel_use_dma_tx(port)) {
+ if (atmel_use_pdc_tx(port)) {
if (UART_GET_PTSR(port) & ATMEL_PDC_TXTEN)
/* The transmitter is already running. Yes, we
really need this.*/
@@ -392,7 +408,7 @@ static void atmel_start_rx(struct uart_port *port)
UART_PUT_CR(port, ATMEL_US_RXEN);
- if (atmel_use_dma_rx(port)) {
+ if (atmel_use_pdc_rx(port)) {
/* enable PDC controller */
UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
port->read_status_mask);
@@ -409,7 +425,7 @@ static void atmel_stop_rx(struct uart_port *port)
{
UART_PUT_CR(port, ATMEL_US_RXDIS);
- if (atmel_use_dma_rx(port)) {
+ if (atmel_use_pdc_rx(port)) {
/* disable PDC receive */
UART_PUT_PTCR(port, ATMEL_PDC_RXTDIS);
UART_PUT_IDR(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
@@ -574,7 +590,7 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (atmel_use_dma_rx(port)) {
+ if (atmel_use_pdc_rx(port)) {
/*
* PDC receive. Just schedule the tasklet and let it
* figure out the details.
@@ -663,7 +679,7 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
/*
* Called from tasklet with ENDTX and TXBUFE interrupts disabled.
*/
-static void atmel_tx_dma(struct uart_port *port)
+static void atmel_tx_pdc(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
struct circ_buf *xmit = &port->state->xmit;
@@ -780,7 +796,7 @@ static void atmel_rx_from_ring(struct uart_port *port)
spin_lock(&port->lock);
}
-static void atmel_rx_from_dma(struct uart_port *port)
+static void atmel_rx_from_pdc(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
struct tty_struct *tty = port->state->port.tty;
@@ -869,8 +885,8 @@ static void atmel_tasklet_func(unsigned long data)
/* The interrupt handler does not take the lock */
spin_lock(&port->lock);
- if (atmel_use_dma_tx(port))
- atmel_tx_dma(port);
+ if (atmel_use_pdc_tx(port))
+ atmel_tx_pdc(port);
else
atmel_tx_chars(port);
@@ -894,8 +910,8 @@ static void atmel_tasklet_func(unsigned long data)
atmel_port->irq_status_prev = status;
}
- if (atmel_use_dma_rx(port))
- atmel_rx_from_dma(port);
+ if (atmel_use_pdc_rx(port))
+ atmel_rx_from_pdc(port);
else
atmel_rx_from_ring(port);
@@ -931,7 +947,7 @@ static int atmel_startup(struct uart_port *port)
/*
* Initialize DMA (if necessary)
*/
- if (atmel_use_dma_rx(port)) {
+ if (atmel_use_pdc_rx(port)) {
int i;
for (i = 0; i < 2; i++) {
@@ -965,7 +981,7 @@ static int atmel_startup(struct uart_port *port)
UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
UART_PUT_RNCR(port, PDC_BUFFER_SIZE);
}
- if (atmel_use_dma_tx(port)) {
+ if (atmel_use_pdc_tx(port)) {
struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
struct circ_buf *xmit = &port->state->xmit;
@@ -1001,7 +1017,7 @@ static int atmel_startup(struct uart_port *port)
/* enable xmit & rcvr */
UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
- if (atmel_use_dma_rx(port)) {
+ if (atmel_use_pdc_rx(port)) {
/* set UART timeout */
UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
UART_PUT_CR(port, ATMEL_US_STTTO);
@@ -1032,7 +1048,7 @@ static void atmel_shutdown(struct uart_port *port)
/*
* Shut-down the DMA.
*/
- if (atmel_use_dma_rx(port)) {
+ if (atmel_use_pdc_rx(port)) {
int i;
for (i = 0; i < 2; i++) {
@@ -1045,7 +1061,7 @@ static void atmel_shutdown(struct uart_port *port)
kfree(pdc->buf);
}
}
- if (atmel_use_dma_tx(port)) {
+ if (atmel_use_pdc_tx(port)) {
struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
dma_unmap_single(port->dev,
@@ -1081,7 +1097,7 @@ static void atmel_flush_buffer(struct uart_port *port)
{
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- if (atmel_use_dma_tx(port)) {
+ if (atmel_use_pdc_tx(port)) {
UART_PUT_TCR(port, 0);
atmel_port->pdc_tx.ofs = 0;
}
@@ -1194,7 +1210,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
if (termios->c_iflag & (BRKINT | PARMRK))
port->read_status_mask |= ATMEL_US_RXBRK;
- if (atmel_use_dma_rx(port))
+ if (atmel_use_pdc_rx(port))
/* need to enable error interrupts */
UART_PUT_IER(port, port->read_status_mask);
@@ -1506,7 +1522,7 @@ static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port,
/* Use TXEMPTY for interrupt when rs485 else TXRDY or ENDTX|TXBUFE */
if (atmel_port->rs485.flags & SER_RS485_ENABLED)
atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
- else if (atmel_use_dma_tx(port)) {
+ else if (atmel_use_pdc_tx(port)) {
port->fifosize = PDC_BUFFER_SIZE;
atmel_port->tx_done_mask = ATMEL_US_ENDTX | ATMEL_US_TXBUFE;
} else {
@@ -1806,7 +1822,7 @@ static int __devinit atmel_serial_probe(struct platform_device *pdev)
atmel_init_port(port, pdev);
- if (!atmel_use_dma_rx(&port->uart)) {
+ if (!atmel_use_pdc_rx(&port->uart)) {
ret = -ENOMEM;
data = kmalloc(sizeof(struct atmel_uart_char)
* ATMEL_SERIAL_RINGSIZE, GFP_KERNEL);
--
1.7.9.5
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