[PATCH] serial: 8250_mtk: support big baud rate.
Long Cheng
long.cheng at mediatek.com
Thu Aug 11 19:41:11 PDT 2016
From: Eddie Huang <eddie.huang at mediatek.com>
mediatek can support baud rate up to 4M.
the 'uart_get_baud_rate' function will limit the max baud rate.
Modify max baud to remove the limit.
Signed-off-by: Long Cheng <long.cheng at mediatek.com>
---
drivers/tty/serial/8250/8250_mtk.c | 6 +-----
drivers/tty/serial/8250/8250_port.c | 4 +---
2 files changed, 2 insertions(+), 8 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index 3611ec9..ce0cc47 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -62,7 +62,7 @@ mtk8250_set_termios(struct uart_port *port, struct ktermios *termios,
*/
baud = uart_get_baud_rate(port, termios, old,
port->uartclk / 16 / 0xffff,
- port->uartclk / 16);
+ port->uartclk);
if (baud <= 115200) {
serial_port_out(port, UART_MTK_HIGHS, 0x0);
@@ -76,10 +76,6 @@ mtk8250_set_termios(struct uart_port *port, struct ktermios *termios,
quot = DIV_ROUND_UP(port->uartclk, 4 * baud);
} else {
serial_port_out(port, UART_MTK_HIGHS, 0x3);
-
- /* Set to highest baudrate supported */
- if (baud >= 1152000)
- baud = 921600;
quot = DIV_ROUND_UP(port->uartclk, 256 * baud);
}
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 7481b95..c45c1e3 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2504,8 +2504,6 @@ static unsigned int serial8250_get_baud_rate(struct uart_port *port,
struct ktermios *termios,
struct ktermios *old)
{
- unsigned int tolerance = port->uartclk / 100;
-
/*
* Ask the core to calculate the divisor for us.
* Allow 1% tolerance at the upper limit so uart clks marginally
@@ -2514,7 +2512,7 @@ static unsigned int serial8250_get_baud_rate(struct uart_port *port,
*/
return uart_get_baud_rate(port, termios, old,
port->uartclk / 16 / 0xffff,
- (port->uartclk + tolerance) / 16);
+ port->uartclk);
}
void
--
1.7.9.5
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