kgdboc,kdb: Allow kdb to work on a non open console port

[sfrench/cifs-2.6.git] / drivers / serial / kgdboc.c

diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index eadc1ab6bbcead8918a19773a7db2f08d85ec0a3..b765ab48dfe7aa9d1f9b771335e34e4c5695f14d 100644 (file)
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -14,7 +14,9 @@
 #include <linux/kernel.h>
 #include <linux/ctype.h>
 #include <linux/kgdb.h>
+#include <linux/kdb.h>
 #include <linux/tty.h>
+#include <linux/console.h>
 
 #define MAX_CONFIG_LEN         40
 
@@ -32,6 +34,40 @@ static struct kparam_string kps = {
 static struct tty_driver       *kgdb_tty_driver;
 static int                     kgdb_tty_line;
 
+#ifdef CONFIG_KDB_KEYBOARD
+static int kgdboc_register_kbd(char **cptr)
+{
+       if (strncmp(*cptr, "kbd", 3) == 0) {
+               if (kdb_poll_idx < KDB_POLL_FUNC_MAX) {
+                       kdb_poll_funcs[kdb_poll_idx] = kdb_get_kbd_char;
+                       kdb_poll_idx++;
+                       if (cptr[0][3] == ',')
+                               *cptr += 4;
+                       else
+                               return 1;
+               }
+       }
+       return 0;
+}
+
+static void kgdboc_unregister_kbd(void)
+{
+       int i;
+
+       for (i = 0; i < kdb_poll_idx; i++) {
+               if (kdb_poll_funcs[i] == kdb_get_kbd_char) {
+                       kdb_poll_idx--;
+                       kdb_poll_funcs[i] = kdb_poll_funcs[kdb_poll_idx];
+                       kdb_poll_funcs[kdb_poll_idx] = NULL;
+                       i--;
+               }
+       }
+}
+#else /* ! CONFIG_KDB_KEYBOARD */
+#define kgdboc_register_kbd(x) 0
+#define kgdboc_unregister_kbd()
+#endif /* ! CONFIG_KDB_KEYBOARD */
+
 static int kgdboc_option_setup(char *opt)
 {
        if (strlen(opt) > MAX_CONFIG_LEN) {
@@ -45,25 +81,51 @@ static int kgdboc_option_setup(char *opt)
 
 __setup("kgdboc=", kgdboc_option_setup);
 
+static void cleanup_kgdboc(void)
+{
+       kgdboc_unregister_kbd();
+       if (configured == 1)
+               kgdb_unregister_io_module(&kgdboc_io_ops);
+}
+
 static int configure_kgdboc(void)
 {
        struct tty_driver *p;
        int tty_line = 0;
        int err;
+       char *cptr = config;
+       struct console *cons;
 
        err = kgdboc_option_setup(config);
        if (err || !strlen(config) || isspace(config[0]))
                goto noconfig;
 
        err = -ENODEV;
+       kgdboc_io_ops.is_console = 0;
+       kgdb_tty_driver = NULL;
 
-       p = tty_find_polling_driver(config, &tty_line);
+       if (kgdboc_register_kbd(&cptr))
+               goto do_register;
+
+       p = tty_find_polling_driver(cptr, &tty_line);
        if (!p)
                goto noconfig;
 
+       cons = console_drivers;
+       while (cons) {
+               int idx;
+               if (cons->device && cons->device(cons, &idx) == p &&
+                   idx == tty_line) {
+                       kgdboc_io_ops.is_console = 1;
+                       break;
+               }
+               cons = cons->next;
+       }
+
        kgdb_tty_driver = p;
        kgdb_tty_line = tty_line;
 
+do_register:
        err = kgdb_register_io_module(&kgdboc_io_ops);
        if (err)
                goto noconfig;
@@ -75,6 +137,7 @@ static int configure_kgdboc(void)
 noconfig:
        config[0] = 0;
        configured = 0;
+       cleanup_kgdboc();
 
        return err;
 }
@@ -88,20 +151,18 @@ static int __init init_kgdboc(void)
        return configure_kgdboc();
 }
 
-static void cleanup_kgdboc(void)
-{
-       if (configured == 1)
-               kgdb_unregister_io_module(&kgdboc_io_ops);
-}
-
 static int kgdboc_get_char(void)
 {
+       if (!kgdb_tty_driver)
+               return -1;
        return kgdb_tty_driver->ops->poll_get_char(kgdb_tty_driver,
                                                kgdb_tty_line);
 }
 
 static void kgdboc_put_char(u8 chr)
 {
+       if (!kgdb_tty_driver)
+               return;
        kgdb_tty_driver->ops->poll_put_char(kgdb_tty_driver,
                                        kgdb_tty_line, chr);
 }