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authorStefan Wahren <stefan.wahren@i2se.com>2015-08-11 14:46:01 +0300
committerBen Hutchings <ben@decadent.org.uk>2017-07-18 20:40:27 +0300
commitc7c3271648c480c81a7eed201c4ff45a46cec8d8 (patch)
tree3ee859477f0f450962caf97ab8ce1712ad452ac1 /drivers/tty/serial
parent9af42458ddd538e10b1ba6d040b644a3bedc4547 (diff)
downloadlinux-c7c3271648c480c81a7eed201c4ff45a46cec8d8.tar.xz
serial: mxs-auart: fix baud rate range
commit df57cf6a879502cd6e5559c1f2d6db12128e074f upstream. Currently mxs-auart doesn't care correctly about the baud rate divisor. According to reference manual the baud rate divisor must be between 0x000000EC and 0x003FFFC0. So calculate the possible baud rate range and use it for uart_get_baud_rate(). Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'drivers/tty/serial')
-rw-r--r--drivers/tty/serial/mxs-auart.c8
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index 86de4477d98a..f421913cb4e9 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -90,6 +90,8 @@
#define AUART_CTRL2_TXE (1 << 8)
#define AUART_CTRL2_UARTEN (1 << 0)
+#define AUART_LINECTRL_BAUD_DIV_MAX 0x003fffc0
+#define AUART_LINECTRL_BAUD_DIV_MIN 0x000000ec
#define AUART_LINECTRL_BAUD_DIVINT_SHIFT 16
#define AUART_LINECTRL_BAUD_DIVINT_MASK 0xffff0000
#define AUART_LINECTRL_BAUD_DIVINT(v) (((v) & 0xffff) << 16)
@@ -566,7 +568,7 @@ static void mxs_auart_settermios(struct uart_port *u,
{
struct mxs_auart_port *s = to_auart_port(u);
u32 bm, ctrl, ctrl2, div;
- unsigned int cflag, baud;
+ unsigned int cflag, baud, baud_min, baud_max;
cflag = termios->c_cflag;
@@ -656,7 +658,9 @@ static void mxs_auart_settermios(struct uart_port *u,
}
/* set baud rate */
- baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk);
+ baud_min = DIV_ROUND_UP(u->uartclk * 32, AUART_LINECTRL_BAUD_DIV_MAX);
+ baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN;
+ baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max);
div = u->uartclk * 32 / baud;
ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F);
ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6);