[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>

1 files changed, 46 insertions, 77 deletions

diff --git a/drivers/serial/suncore.c b/drivers/serial/suncore.c
index b45ba53..70a09a3 100644
--- a/drivers/serial/suncore.c
+++ b/drivers/serial/suncore.c
@@ -16,9 +16,10 @@
 #include <linux/tty.h>
 #include <linux/errno.h>
 #include <linux/string.h>
+#include <linux/serial_core.h>
 #include <linux/init.h>
 
-#include <asm/oplib.h>
+#include <asm/prom.h>
 
 #include "suncore.h"
 
@@ -26,92 +27,60 @@ int sunserial_current_minor = 64;
 
 EXPORT_SYMBOL(sunserial_current_minor);
 
-void
-sunserial_console_termios(struct console *con)
+int sunserial_console_match(struct console *con, struct device_node *dp,
+			    struct uart_driver *drv, int line)
 {
-	char mode[16], buf[16], *s;
-	char mode_prop[] = "ttyX-mode";
-	char cd_prop[]   = "ttyX-ignore-cd";
-	char dtr_prop[]  = "ttyX-rts-dtr-off";
-	char *ssp_console_modes_prop = "ssp-console-modes";
-	int baud, bits, stop, cflag;
-	char parity;
-	int carrier = 0;
-	int rtsdtr = 1;
-	int topnd, nd;
-
-	if (!serial_console)
-		return;
-
-	switch (serial_console) {
-	case PROMDEV_OTTYA:
-		mode_prop[3] = 'a';
-		cd_prop[3] = 'a';
-		dtr_prop[3] = 'a';
-		break;
-
-	case PROMDEV_OTTYB:
-		mode_prop[3] = 'b';
-		cd_prop[3] = 'b';
-		dtr_prop[3] = 'b';
-		break;
-
-	case PROMDEV_ORSC:
-
-		nd = prom_pathtoinode("rsc");
-		if (!nd) {
-			strcpy(mode, "115200,8,n,1,-");
-			goto no_options;
-		}
+	int off;
 
-		if (!prom_node_has_property(nd, ssp_console_modes_prop)) {
-			strcpy(mode, "115200,8,n,1,-");
-			goto no_options;
-		}
+	if (!con || of_console_device != dp)
+		return 0;
 
-		memset(mode, 0, sizeof(mode));
-		prom_getstring(nd, ssp_console_modes_prop, mode, sizeof(mode));
-		goto no_options;
+	off = 0;
+	if (of_console_options &&
+	    *of_console_options == 'b')
+		off = 1;
 
-	default:
-		strcpy(mode, "9600,8,n,1,-");
-		goto no_options;
-	}
+	if ((line & 1) != off)
+		return 0;
 
-	topnd = prom_getchild(prom_root_node);
-	nd = prom_searchsiblings(topnd, "options");
-	if (!nd) {
-		strcpy(mode, "9600,8,n,1,-");
-		goto no_options;
-	}
-
-	if (!prom_node_has_property(nd, mode_prop)) {
-		strcpy(mode, "9600,8,n,1,-");
-		goto no_options;
-	}
+	con->index = line;
+	drv->cons = con;
+	add_preferred_console(con->name, line, NULL);
 
-	memset(mode, 0, sizeof(mode));
-	prom_getstring(nd, mode_prop, mode, sizeof(mode));
-
-	if (prom_node_has_property(nd, cd_prop)) {
-		memset(buf, 0, sizeof(buf));
-		prom_getstring(nd, cd_prop, buf, sizeof(buf));
-		if (!strcmp(buf, "false"))
-			carrier = 1;
-
-		/* XXX: this is unused below. */
-	}
+	return 1;
+}
+EXPORT_SYMBOL(sunserial_console_match);
 
-	if (prom_node_has_property(nd, dtr_prop)) {
-		memset(buf, 0, sizeof(buf));
-		prom_getstring(nd, dtr_prop, buf, sizeof(buf));
-		if (!strcmp(buf, "false"))
-			rtsdtr = 0;
+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;
 
-		/* XXX: this is unused below. */
+	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,-";
 	}
 
-no_options:
 	cflag = CREAD | HUPCL | CLOCAL;
 
 	s = mode;