fbcon: allow fbcon to use the primary display driver

Allow fbcon to select the primary display adapter using the
fb_is_primary_device() arch-specific helper.  If a a primary adapter is
detected, fbcon will unbind the old adapter from the VT layer, then rebind
using the new adapter.  This requires that bind_/unbind_con_driver() be made
public.

Because this feature may produce unexpected behavior (from the user's POV),
this must be explicitly enabled in Kconfig.

[akpm@linux-foundation.org: export unbind_con_driver]
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/i386/video/fbdev.c b/arch/i386/video/fbdev.c
index 7fc712c..48fb38d 100644 (file)
--- a/arch/i386/video/fbdev.c
+++ b/arch/i386/video/fbdev.c
@@ -13,13 +13,11 @@
 
 int fb_is_primary_device(struct fb_info *info)
 {
-       struct device *device;
+       struct device *device = info->device;
        struct pci_dev *pci_dev = NULL;
        struct resource *res = NULL;
        int retval = 0;
 
-       device = info->device;
-
        if (device)
                pci_dev = to_pci_dev(device);
 

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 349673d..8a389b3 100644 (file)
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -2869,8 +2869,7 @@ int __init vty_init(void)
 
 static struct class *vtconsole_class;
 
-static int bind_con_driver(const struct consw *csw, int first, int last,
-                          int deflt)
+int bind_con_driver(const struct consw *csw, int first, int last, int deflt)
 {
        struct module *owner = csw->owner;
        const char *desc = NULL;
@@ -2969,6 +2968,7 @@ err:
        module_put(owner);
        return retval;
 };
+EXPORT_SYMBOL(bind_con_driver);
 
 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
 static int con_is_graphics(const struct consw *csw, int first, int last)
@@ -2987,8 +2987,7 @@ static int con_is_graphics(const struct consw *csw, int first, int last)
        return retval;
 }
 
-static int unbind_con_driver(const struct consw *csw, int first, int last,
-                            int deflt)
+int unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
 {
        struct module *owner = csw->owner;
        const struct consw *defcsw = NULL;
@@ -3073,6 +3072,7 @@ err:
        return retval;
 
 }
+EXPORT_SYMBOL(unbind_con_driver);
 
 static int vt_bind(struct con_driver *con)
 {

diff --git a/drivers/video/console/Kconfig b/drivers/video/console/Kconfig
index d3b8a6b..160f55f 100644 (file)
--- a/drivers/video/console/Kconfig
+++ b/drivers/video/console/Kconfig
@@ -118,6 +118,26 @@ config FRAMEBUFFER_CONSOLE
        help
          Low-level framebuffer-based console driver.
 
+config FRAMEBUFFER_CONSOLE_DETECT_PRIMARY
+       bool "Map the console to the primary display device"
+       depends on FRAMEBUFFER_CONSOLE && VT_HW_CONSOLE_BINDING
+       default n
+       ---help---
+         If this option is selected, the framebuffer console will
+         automatically select the primary display device (if the architecture
+        supports this feature).  Otherwise, the framebuffer console will
+         always select the first framebuffer driver that is loaded. The latter
+         is the default behavior.
+
+        You can always override the automatic selection of the primary device
+        by using the fbcon=map: boot option.
+
+        To select this feature, "Support for binding and unbinding console
+         drivers", under "Device Drivers"->"Character Devices" must be set to
+        y.
+
+        If unsure, select n.
+
 config FRAMEBUFFER_CONSOLE_ROTATION
        bool "Framebuffer Console Rotation"
        depends on FRAMEBUFFER_CONSOLE

diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 7f4ed79..7ba21eb 100644 (file)
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -75,6 +75,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/crc32.h> /* For counting font checksums */
+#include <asm/fb.h>
 #include <asm/irq.h>
 #include <asm/system.h>
 #include <asm/uaccess.h>
@@ -125,6 +126,8 @@ static int first_fb_vc;
 static int last_fb_vc = MAX_NR_CONSOLES - 1;
 static int fbcon_is_default = 1; 
 static int fbcon_has_exited;
+static int primary_device = -1;
+static int map_override;
 
 /* font data */
 static char fontname[40];
@@ -497,13 +500,17 @@ static int __init fb_console_setup(char *this_opt)
                
                if (!strncmp(options, "map:", 4)) {
                        options += 4;
-                       if (*options)
+                       if (*options) {
                                for (i = 0, j = 0; i < MAX_NR_CONSOLES; i++) {
                                        if (!options[j])
                                                j = 0;
                                        con2fb_map_boot[i] =
                                                (options[j++]-'0') % FB_MAX;
                                }
+
+                               map_override = 1;
+                       }
+
                        return 1;
                }
 
@@ -3004,9 +3011,9 @@ static int fbcon_mode_deleted(struct fb_info *info,
        return found;
 }
 
-static int fbcon_fb_unregistered(int idx)
+static int fbcon_fb_unregistered(struct fb_info *info)
 {
-       int i;
+       int i, idx = info->node;
 
        for (i = first_fb_vc; i <= last_fb_vc; i++) {
                if (con2fb_map[i] == idx)
@@ -3034,12 +3041,70 @@ static int fbcon_fb_unregistered(int idx)
        if (!num_registered_fb)
                unregister_con_driver(&fb_con);
 
+
+       if (primary_device == idx)
+               primary_device = -1;
+
+       return 0;
+}
+
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY
+static int fbcon_select_primary(struct fb_info *info)
+{
+       int ret = 0;
+
+       if (!map_override && primary_device == -1 &&
+           fb_is_primary_device(info)) {
+               int i, err;
+
+               printk(KERN_INFO "fbcon: %s is primary device\n",
+                      info->fix.id);
+               primary_device = info->node;
+
+               if (!con_is_bound(&fb_con))
+                       goto done;
+
+               printk(KERN_INFO "fbcon: Unbinding old driver\n");
+               unbind_con_driver(&fb_con, first_fb_vc, last_fb_vc,
+                                 fbcon_is_default);
+               info_idx = primary_device;
+
+               for (i = first_fb_vc; i <= last_fb_vc; i++) {
+                       con2fb_map_boot[i] = primary_device;
+                       con2fb_map[i] = primary_device;
+               }
+
+               printk(KERN_INFO "fbcon: Selecting new driver\n");
+               err = bind_con_driver(&fb_con, first_fb_vc, last_fb_vc,
+                                     fbcon_is_default);
+
+               if (err) {
+                       for (i = first_fb_vc; i <= last_fb_vc; i++)
+                               con2fb_map[i] = -1;
+
+                       info_idx = -1;
+               }
+
+               ret = 1;
+       }
+
+done:
+       return ret;
+}
+#else
+static inline int fbcon_select_primary(struct fb_info *info)
+{
        return 0;
 }
+#endif /* CONFIG_FRAMEBUFFER_DETECT_PRIMARY */
 
-static int fbcon_fb_registered(int idx)
+static int fbcon_fb_registered(struct fb_info *info)
 {
-       int ret = 0, i;
+       int ret = 0, i, idx = info->node;
+
+       if (fbcon_select_primary(info))
+               goto done;
+
 
        if (info_idx == -1) {
                for (i = first_fb_vc; i <= last_fb_vc; i++) {
@@ -3059,6 +3124,7 @@ static int fbcon_fb_registered(int idx)
                }
        }
 
+done:
        return ret;
 }
 
@@ -3182,10 +3248,10 @@ static int fbcon_event_notify(struct notifier_block *self,
                ret = fbcon_mode_deleted(info, mode);
                break;
        case FB_EVENT_FB_REGISTERED:
-               ret = fbcon_fb_registered(info->node);
+               ret = fbcon_fb_registered(info);
                break;
        case FB_EVENT_FB_UNREGISTERED:
-               ret = fbcon_fb_unregistered(info->node);
+               ret = fbcon_fb_unregistered(info);
                break;
        case FB_EVENT_SET_CONSOLE_MAP:
                con2fb = event->data;

diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h
index d961635..0d034d8 100644 (file)
--- a/include/linux/vt_kern.h
+++ b/include/linux/vt_kern.h
@@ -75,6 +75,10 @@ int con_copy_unimap(struct vc_data *dst_vc, struct vc_data *src_vc);
 int vt_waitactive(int vt);
 void change_console(struct vc_data *new_vc);
 void reset_vc(struct vc_data *vc);
+extern int bind_con_driver(const struct consw *csw, int first, int last,
+                          int deflt);
+extern int unbind_con_driver(const struct consw *csw, int first, int last,
+                            int deflt);
 
 /*
  * vc_screen.c shares this temporary buffer with the console write code so that