serial: 8250_pci: more BayTrail error-free bauds

Support the following additional baud rates with 0% error:
	500000, 1500000, 2500000, 3500000

Signed-off-by: Aaron Sierra <asierra@xes-inc.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Aaron Sierra 2014-03-03 19:54:29 -06:00 committed by Greg Kroah-Hartman
parent 013daec9c1
commit 50825c57ab

View File

@ -1366,22 +1366,43 @@ byt_set_termios(struct uart_port *p, struct ktermios *termios,
struct ktermios *old)
{
unsigned int baud = tty_termios_baud_rate(termios);
unsigned int m = 6912;
unsigned int n = 15625;
unsigned int m, n;
u32 reg;
/* For baud rates 1M, 2M, 3M and 4M the dividers must be adjusted. */
if (baud == 1000000 || baud == 2000000 || baud == 4000000) {
/*
* For baud rates 0.5M, 1M, 1.5M, 2M, 2.5M, 3M, 3.5M and 4M the
* dividers must be adjusted.
*
* uartclk = (m / n) * 100 MHz, where m <= n
*/
switch (baud) {
case 500000:
case 1000000:
case 2000000:
case 4000000:
m = 64;
n = 100;
p->uartclk = 64000000;
} else if (baud == 3000000) {
break;
case 3500000:
m = 56;
n = 100;
p->uartclk = 56000000;
break;
case 1500000:
case 3000000:
m = 48;
n = 100;
p->uartclk = 48000000;
} else {
break;
case 2500000:
m = 40;
n = 100;
p->uartclk = 40000000;
break;
default:
m = 6912;
n = 15625;
p->uartclk = 44236800;
}