static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
struct ktermios *old)
{
unsigned int baud = tty_termios_baud_rate(termios);
struct dw8250_data *d = p->private_data;
unsigned int rate;
int ret;
if (IS_ERR(d->clk) || !old)
goto out;
/* Not requesting clock rates below 1.8432Mhz */
if (baud < 115200)
baud = 115200;
clk_disable_unprepare(d->clk);
rate = clk_round_rate(d->clk, baud * 16);
ret = clk_set_rate(d->clk, rate);
clk_prepare_enable(d->clk);
if (!ret)
p->uartclk = rate;
p->status &= ~UPSTAT_AUTOCTS;
if (termios->c_cflag & CRTSCTS)
p->status |= UPSTAT_AUTOCTS;
out:
serial8250_do_set_termios(p, termios, old);
}
static void
mtk8250_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct uart_8250_port *up = up_to_u8250p(port);
unsigned long flags;
unsigned int baud, quot;
#ifdef CONFIG_SERIAL_8250_DMA
if (up->dma) {
if (uart_console(port)) {
devm_kfree(up->port.dev, up->dma);
up->dma = NULL;
} else {
mtk8250_dma_enable(up);
}
}
#endif
serial8250_do_set_termios(port, termios, old);
/*
* Mediatek UARTs use an extra highspeed register (UART_MTK_HIGHS)
*
* We need to recalcualte the quot register, as the claculation depends
* on the vaule in the highspeed register.
*
* Some baudrates are not supported by the chip, so we use the next
* lower rate supported and update termios c_flag.
*
* If highspeed register is set to 3, we need to specify sample count
* and sample point to increase accuracy. If not, we reset the
* registers to their default values.
*/
baud = uart_get_baud_rate(port, termios, old,
port->uartclk / 16 / UART_DIV_MAX,
port->uartclk);
if (baud <= 115200) {
serial_port_out(port, UART_MTK_HIGHS, 0x0);
quot = uart_get_divisor(port, baud);
} else if (baud <= 576000) {
serial_port_out(port, UART_MTK_HIGHS, 0x2);
/* Set to next lower baudrate supported */
if ((baud == 500000) || (baud == 576000))
baud = 460800;
quot = DIV_ROUND_UP(port->uartclk, 4 * baud);
} else {
serial_port_out(port, UART_MTK_HIGHS, 0x3);
quot = DIV_ROUND_UP(port->uartclk, 256 * baud);
}
/*
* Ok, we're now changing the port state. Do it with
* interrupts disabled.
*/
spin_lock_irqsave(&port->lock, flags);
/* set DLAB we have cval saved in up->lcr from the call to the core */
serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB);
serial_dl_write(up, quot);
/* reset DLAB */
serial_port_out(port, UART_LCR, up->lcr);
if (baud > 460800) {
unsigned int tmp;
tmp = DIV_ROUND_CLOSEST(port->uartclk, quot * baud);
serial_port_out(port, UART_MTK_SAMPLE_COUNT, tmp - 1);
serial_port_out(port, UART_MTK_SAMPLE_POINT,
(tmp - 2) >> 1);
} else {
