tty: Update hypervisor tty drivers to use core stdout parsing code.

The evh_bytechan, hvc_opal and hvc_vio drivers all open code the parsing
of the stdout node in the device tree. This patch simplifies the driver
by removing the duplicated functionality.

Signed-off-by: Grant Likely <grant.likely@linaro.org>

drivers/tty/hvc/hvc_opal.c

@@ -342,22 +342,13 @@ static void udbg_init_opal_common(void)
 
 void __init hvc_opal_init_early(void)
 {
-	struct device_node *stdout_node = NULL;
+	struct device_node *stdout_node = of_node_get(of_stdout);
 	const __be32 *termno;
-	const char *name = NULL;
 	const struct hv_ops *ops;
 	u32 index;
 
-	/* find the boot console from /chosen/stdout */
-	if (of_chosen)
-		name = of_get_property(of_chosen, "linux,stdout-path", NULL);
-	if (name) {
-		stdout_node = of_find_node_by_path(name);
-		if (!stdout_node) {
-			pr_err("hvc_opal: Failed to locate default console!\n");
-			return;
-		}
-	} else {
+	/* If the console wasn't in /chosen, try /ibm,opal */
+	if (!stdout_node) {
 		struct device_node *opal, *np;
 
 		/* Current OPAL takeover doesn't provide the stdout

drivers/tty/hvc/hvc_vio.c

@@ -404,42 +404,35 @@ module_exit(hvc_vio_exit);
 
 void __init hvc_vio_init_early(void)
 {
-	struct device_node *stdout_node;
 	const __be32 *termno;
 	const char *name;
 	const struct hv_ops *ops;
 
 	/* find the boot console from /chosen/stdout */
-	if (!of_chosen)
+	if (!of_stdout)
 		return;
-	name = of_get_property(of_chosen, "linux,stdout-path", NULL);
-	if (name == NULL)
-		return;
-	stdout_node = of_find_node_by_path(name);
-	if (!stdout_node)
-		return;
-	name = of_get_property(stdout_node, "name", NULL);
+	name = of_get_property(of_stdout, "name", NULL);
 	if (!name) {
 		printk(KERN_WARNING "stdout node missing 'name' property!\n");
-		goto out;
+		return;
 	}
 
 	/* Check if it's a virtual terminal */
 	if (strncmp(name, "vty", 3) != 0)
-		goto out;
-	termno = of_get_property(stdout_node, "reg", NULL);
+		return;
+	termno = of_get_property(of_stdout, "reg", NULL);
 	if (termno == NULL)
-		goto out;
+		return;
 	hvterm_priv0.termno = of_read_number(termno, 1);
 	spin_lock_init(&hvterm_priv0.buf_lock);
 	hvterm_privs[0] = &hvterm_priv0;
 
 	/* Check the protocol */
-	if (of_device_is_compatible(stdout_node, "hvterm1")) {
+	if (of_device_is_compatible(of_stdout, "hvterm1")) {
 		hvterm_priv0.proto = HV_PROTOCOL_RAW;
 		ops = &hvterm_raw_ops;
 	}
-	else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) {
+	else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
 		hvterm_priv0.proto = HV_PROTOCOL_HVSI;
 		ops = &hvterm_hvsi_ops;
 		hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
@@ -447,7 +440,7 @@ void __init hvc_vio_init_early(void)
 		/* HVSI, perform the handshake now */
 		hvsilib_establish(&hvterm_priv0.hvsi);
 	} else
-		goto out;
+		return;
 	udbg_putc = udbg_hvc_putc;
 	udbg_getc = udbg_hvc_getc;
 	udbg_getc_poll = udbg_hvc_getc_poll;
@@ -456,14 +449,12 @@ void __init hvc_vio_init_early(void)
 	 * backend for HVSI, only do udbg
 	 */
 	if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
-		goto out;
+		return;
 #endif
 	/* Check whether the user has requested a different console. */
 	if (!strstr(cmd_line, "console="))
 		add_preferred_console("hvc", 0, NULL);
 	hvc_instantiate(0, 0, ops);
-out:
-	of_node_put(stdout_node);
 }
 
 /* call this from early_init() for a working debug console on