alistair23-linux/drivers/serial/suncore.c
David S. Miller c73fcc846c [SPARC]: Fix serial console device detection.
The current scheme works on static interpretation of text names, which
is wrong.

The output-device setting, for example, must be resolved via an alias
or similar to a full path name to the console device.

Paths also contain an optional set of 'options', which starts with a
colon at the end of the path.  The option area is used to specify
which of two serial ports ('a' or 'b') the path refers to when a
device node drives multiple ports.  'a' is assumed if the option
specification is missing.

This was caught by the UltraSPARC-T1 simulator.  The 'output-device'
property was set to 'ttya' and we didn't pick upon the fact that this
is an OBP alias set to '/virtual-devices/console'.  Instead we saw it
as the first serial console device, instead of the hypervisor console.

The infrastructure is now there to take advantage of this to resolve
the console correctly even in multi-head situations in fbcon too.

Thanks to Greg Onufer for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-20 16:59:26 -07:00

217 lines
4.4 KiB
C

/* suncore.c
*
* Common SUN serial routines. Based entirely
* upon drivers/sbus/char/sunserial.c which is:
*
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
*
* Adaptation to new UART layer is:
*
* Copyright (C) 2002 David S. Miller (davem@redhat.com)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/console.h>
#include <linux/tty.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/serial_core.h>
#include <linux/init.h>
#include <asm/prom.h>
#include "suncore.h"
int sunserial_current_minor = 64;
EXPORT_SYMBOL(sunserial_current_minor);
int sunserial_console_match(struct console *con, struct device_node *dp,
struct uart_driver *drv, int line)
{
int off;
if (!con || of_console_device != dp)
return 0;
off = 0;
if (of_console_options &&
*of_console_options == 'b')
off = 1;
if ((line & 1) != off)
return 0;
con->index = line;
drv->cons = con;
add_preferred_console(con->name, line, NULL);
return 1;
}
EXPORT_SYMBOL(sunserial_console_match);
void
sunserial_console_termios(struct console *con)
{
struct device_node *dp;
const char *od, *mode, *s;
char mode_prop[] = "ttyX-mode";
int baud, bits, stop, cflag;
char parity;
dp = of_find_node_by_path("/options");
od = of_get_property(dp, "output-device", NULL);
if (!strcmp(od, "rsc")) {
mode = of_get_property(of_console_device,
"ssp-console-modes", NULL);
if (!mode)
mode = "115200,8,n,1,-";
} else {
char c;
c = 'a';
if (of_console_options)
c = *of_console_options;
mode_prop[3] = c;
mode = of_get_property(dp, mode_prop, NULL);
if (!mode)
mode = "9600,8,n,1,-";
}
cflag = CREAD | HUPCL | CLOCAL;
s = mode;
baud = simple_strtoul(s, NULL, 0);
s = strchr(s, ',');
bits = simple_strtoul(++s, NULL, 0);
s = strchr(s, ',');
parity = *(++s);
s = strchr(s, ',');
stop = simple_strtoul(++s, NULL, 0);
s = strchr(s, ',');
/* XXX handshake is not handled here. */
switch (baud) {
case 150: cflag |= B150; break;
case 300: cflag |= B300; break;
case 600: cflag |= B600; break;
case 1200: cflag |= B1200; break;
case 2400: cflag |= B2400; break;
case 4800: cflag |= B4800; break;
case 9600: cflag |= B9600; break;
case 19200: cflag |= B19200; break;
case 38400: cflag |= B38400; break;
case 57600: cflag |= B57600; break;
case 115200: cflag |= B115200; break;
case 230400: cflag |= B230400; break;
case 460800: cflag |= B460800; break;
default: baud = 9600; cflag |= B9600; break;
}
switch (bits) {
case 5: cflag |= CS5; break;
case 6: cflag |= CS6; break;
case 7: cflag |= CS7; break;
case 8: cflag |= CS8; break;
default: cflag |= CS8; break;
}
switch (parity) {
case 'o': cflag |= (PARENB | PARODD); break;
case 'e': cflag |= PARENB; break;
case 'n': default: break;
}
switch (stop) {
case 2: cflag |= CSTOPB; break;
case 1: default: break;
}
con->cflag = cflag;
}
EXPORT_SYMBOL(sunserial_console_termios);
/* Sun serial MOUSE auto baud rate detection. */
static struct mouse_baud_cflag {
int baud;
unsigned int cflag;
} mouse_baud_table[] = {
{ 1200, B1200 },
{ 2400, B2400 },
{ 4800, B4800 },
{ 9600, B9600 },
{ -1, ~0 },
{ -1, ~0 },
};
unsigned int suncore_mouse_baud_cflag_next(unsigned int cflag, int *new_baud)
{
int i;
for (i = 0; mouse_baud_table[i].baud != -1; i++)
if (mouse_baud_table[i].cflag == (cflag & CBAUD))
break;
i += 1;
if (mouse_baud_table[i].baud == -1)
i = 0;
*new_baud = mouse_baud_table[i].baud;
return mouse_baud_table[i].cflag;
}
EXPORT_SYMBOL(suncore_mouse_baud_cflag_next);
/* Basically, when the baud rate is wrong the mouse spits out
* breaks to us.
*/
int suncore_mouse_baud_detection(unsigned char ch, int is_break)
{
static int mouse_got_break = 0;
static int ctr = 0;
if (is_break) {
/* Let a few normal bytes go by before we jump the gun
* and say we need to try another baud rate.
*/
if (mouse_got_break && ctr < 8)
return 1;
/* Ok, we need to try another baud. */
ctr = 0;
mouse_got_break = 1;
return 2;
}
if (mouse_got_break) {
ctr++;
if (ch == 0x87) {
/* Correct baud rate determined. */
mouse_got_break = 0;
}
return 1;
}
return 0;
}
EXPORT_SYMBOL(suncore_mouse_baud_detection);
static int __init suncore_init(void)
{
return 0;
}
static void __exit suncore_exit(void)
{
}
module_init(suncore_init);
module_exit(suncore_exit);
MODULE_AUTHOR("Eddie C. Dost, David S. Miller");
MODULE_DESCRIPTION("Sun serial common layer");
MODULE_LICENSE("GPL");