[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>

6 files changed, 65 insertions, 142 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;
diff --git a/drivers/serial/suncore.h b/drivers/serial/suncore.h
index 513916a..829d7d6 100644
--- a/drivers/serial/suncore.h
+++ b/drivers/serial/suncore.h
@@ -24,6 +24,8 @@ extern int suncore_mouse_baud_detection(unsigned char, int);
 
 extern int sunserial_current_minor;
 
+extern int sunserial_console_match(struct console *, struct device_node *,
+				   struct uart_driver *, int);
 extern void sunserial_console_termios(struct console *);
 
 #endif /* !(_SERIAL_SUN_H) */
diff --git a/drivers/serial/sunhv.c b/drivers/serial/sunhv.c
index d82be42..8ff900b 100644
--- a/drivers/serial/sunhv.c
+++ b/drivers/serial/sunhv.c
@@ -520,16 +520,6 @@ static struct console sunhv_console = {
 	.data	=	&sunhv_reg,
 };
 
-static inline struct console *SUNHV_CONSOLE(void)
-{
-	if (con_is_present())
-		return NULL;
-
-	sunhv_console.index = 0;
-
-	return &sunhv_console;
-}
-
 static int __devinit hv_probe(struct of_device *op, const struct of_device_id *match)
 {
 	struct uart_port *port;
@@ -582,7 +572,8 @@ static int __devinit hv_probe(struct of_device *op, const struct of_device_id *m
 	sunhv_reg.tty_driver->name_base = sunhv_reg.minor - 64;
 	sunserial_current_minor += 1;
 
-	sunhv_reg.cons = SUNHV_CONSOLE();
+	sunserial_console_match(&sunhv_console, op->node,
+				&sunhv_reg, port->line);
 
 	err = uart_add_one_port(&sunhv_reg, port);
 	if (err)
diff --git a/drivers/serial/sunsab.c b/drivers/serial/sunsab.c
index 8a0f9e4..bca57bb 100644
--- a/drivers/serial/sunsab.c
+++ b/drivers/serial/sunsab.c
@@ -968,22 +968,6 @@ static struct console sunsab_console = {
 
 static inline struct console *SUNSAB_CONSOLE(void)
 {
-	int i;
-
-	if (con_is_present())
-		return NULL;
-
-	for (i = 0; i < num_channels; i++) {
-		int this_minor = sunsab_reg.minor + i;
-
-		if ((this_minor - 64) == (serial_console - 1))
-			break;
-	}
-	if (i == num_channels)
-		return NULL;
-
-	sunsab_console.index = i;
-
 	return &sunsab_console;
 }
 #else
@@ -1080,7 +1064,12 @@ static int __devinit sab_probe(struct of_device *op, const struct of_device_id *
 		return err;
 	}
 
+	sunserial_console_match(SUNSAB_CONSOLE(), op->node,
+				&sunsab_reg, up[0].port.line);
 	uart_add_one_port(&sunsab_reg, &up[0].port);
+
+	sunserial_console_match(SUNSAB_CONSOLE(), op->node,
+				&sunsab_reg, up[1].port.line);
 	uart_add_one_port(&sunsab_reg, &up[1].port);
 
 	dev_set_drvdata(&op->dev, &up[0]);
@@ -1164,7 +1153,6 @@ static int __init sunsab_init(void)
 		}
 
 		sunsab_reg.tty_driver->name_base = sunsab_reg.minor - 64;
-		sunsab_reg.cons = SUNSAB_CONSOLE();
 		sunserial_current_minor += num_channels;
 	}
 
diff --git a/drivers/serial/sunsu.c b/drivers/serial/sunsu.c
index 26d720b..79b1368 100644
--- a/drivers/serial/sunsu.c
+++ b/drivers/serial/sunsu.c
@@ -1371,28 +1371,12 @@ static struct console sunsu_console = {
  *	Register console.
  */
 
-static inline struct console *SUNSU_CONSOLE(int num_uart)
+static inline struct console *SUNSU_CONSOLE(void)
 {
-	int i;
-
-	if (con_is_present())
-		return NULL;
-
-	for (i = 0; i < num_uart; i++) {
-		int this_minor = sunsu_reg.minor + i;
-
-		if ((this_minor - 64) == (serial_console - 1))
-			break;
-	}
-	if (i == num_uart)
-		return NULL;
-
-	sunsu_console.index = i;
-
 	return &sunsu_console;
 }
 #else
-#define SUNSU_CONSOLE(num_uart)		(NULL)
+#define SUNSU_CONSOLE()			(NULL)
 #define sunsu_serial_console_init()	do { } while (0)
 #endif
 
@@ -1482,6 +1466,8 @@ static int __devinit su_probe(struct of_device *op, const struct of_device_id *m
 
 	up->port.ops = &sunsu_pops;
 
+	sunserial_console_match(SUNSU_CONSOLE(), dp,
+				&sunsu_reg, up->port.line);
 	err = uart_add_one_port(&sunsu_reg, &up->port);
 	if (err)
 		goto out_unmap;
@@ -1572,7 +1558,6 @@ static int __init sunsu_init(void)
 			return err;
 		sunsu_reg.tty_driver->name_base = sunsu_reg.minor - 64;
 		sunserial_current_minor += num_uart;
-		sunsu_reg.cons = SUNSU_CONSOLE(num_uart);
 	}
 
 	err = of_register_driver(&su_driver, &of_bus_type);
diff --git a/drivers/serial/sunzilog.c b/drivers/serial/sunzilog.c
index 0a3e10a..1d262c0 100644
--- a/drivers/serial/sunzilog.c
+++ b/drivers/serial/sunzilog.c
@@ -1226,23 +1226,6 @@ static struct console sunzilog_console_ops = {
 
 static inline struct console *SUNZILOG_CONSOLE(void)
 {
-	int i;
-
-	if (con_is_present())
-		return NULL;
-
-	for (i = 0; i < NUM_CHANNELS; i++) {
-		int this_minor = sunzilog_reg.minor + i;
-
-		if ((this_minor - 64) == (serial_console - 1))
-			break;
-	}
-	if (i == NUM_CHANNELS)
-		return NULL;
-
-	sunzilog_console_ops.index = i;
-	sunzilog_port_table[i].flags |= SUNZILOG_FLAG_IS_CONS;
-
 	return &sunzilog_console_ops;
 }
 
@@ -1428,12 +1411,18 @@ static int __devinit zs_probe(struct of_device *op, const struct of_device_id *m
 	sunzilog_init_hw(&up[1]);
 
 	if (!keyboard_mouse) {
+		if (sunserial_console_match(SUNZILOG_CONSOLE(), op->node,
+					    &sunzilog_reg, up[0].port.line))
+			up->flags |= SUNZILOG_FLAG_IS_CONS;
 		err = uart_add_one_port(&sunzilog_reg, &up[0].port);
 		if (err) {
 			of_iounmap(&op->resource[0],
 				   rp, sizeof(struct zilog_layout));
 			return err;
 		}
+		if (sunserial_console_match(SUNZILOG_CONSOLE(), op->node,
+					    &sunzilog_reg, up[1].port.line))
+			up->flags |= SUNZILOG_FLAG_IS_CONS;
 		err = uart_add_one_port(&sunzilog_reg, &up[1].port);
 		if (err) {
 			uart_remove_one_port(&sunzilog_reg, &up[0].port);
@@ -1531,7 +1520,6 @@ static int __init sunzilog_init(void)
 			goto out_free_tables;
 
 		sunzilog_reg.tty_driver->name_base = sunzilog_reg.minor - 64;
-		sunzilog_reg.cons = SUNZILOG_CONSOLE();
 
 		sunserial_current_minor += uart_count;
 	}