static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
{
struct s3c24xx_uart_port *ourport = id;
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
int count = 256;
if (port->x_char) {
wr_regb(port, S3C2410_UTXH, port->x_char);
port->icount.tx++;
port->x_char = 0;
goto out;
}
/* if there isnt anything more to transmit, or the uart is now
* stopped, disable the uart and exit
*/
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
s3c24xx_serial_stop_tx(port);
goto out;
}
/* try and drain the buffer... */
while (!uart_circ_empty(xmit) && count-- > 0) {
if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
break;
wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(port);
if (uart_circ_empty(xmit))
s3c24xx_serial_stop_tx(port);
out:
return IRQ_HANDLED;
}
static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
{
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long count;
/* Get data size up to the end of buffer */
count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (!count) {
s3c24xx_serial_stop_tx(port);
return;
}
if (!ourport->dma || !ourport->dma->tx_chan ||
count < ourport->min_dma_size ||
xmit->tail & (dma_get_cache_alignment() - 1))
s3c24xx_serial_start_tx_pio(ourport);
else
s3c24xx_serial_start_tx_dma(ourport, count);
}
static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
{
struct s3c24xx_uart_port *ourport = id;
struct uart_port *port = &ourport->port;
struct circ_buf *xmit = &port->state->xmit;
unsigned long flags;
int count, dma_count = 0;
spin_lock_irqsave(&port->lock, flags);
count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (ourport->dma && ourport->dma->tx_chan &&
count >= ourport->min_dma_size) {
int align = dma_get_cache_alignment() -
(xmit->tail & (dma_get_cache_alignment() - 1));
if (count-align >= ourport->min_dma_size) {
dma_count = count-align;
count = align;
}
}
if (port->x_char) {
wr_regb(port, S3C2410_UTXH, port->x_char);
port->icount.tx++;
port->x_char = 0;
goto out;
}
/* if there isn't anything more to transmit, or the uart is now
* stopped, disable the uart and exit
*/
if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
s3c24xx_serial_stop_tx(port);
goto out;
}
/* try and drain the buffer... */
if (count > port->fifosize) {
count = port->fifosize;
dma_count = 0;
}
while (!uart_circ_empty(xmit) && count > 0) {
if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
break;
wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
count--;
}
if (!count && dma_count) {
s3c24xx_serial_start_tx_dma(ourport, dma_count);
goto out;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
spin_unlock(&port->lock);
uart_write_wakeup(port);
spin_lock(&port->lock);
}
if (uart_circ_empty(xmit))
s3c24xx_serial_stop_tx(port);
out:
spin_unlock_irqrestore(&port->lock, flags);
return IRQ_HANDLED;
}
