PM: earlysuspend: Add console switch when user requested sleep state changes.
Arve Hjønnevåg [Thu, 16 Oct 2008 00:52:20 +0000 (17:52 -0700)]
Signed-off-by: Arve Hjønnevåg <arve@android.com>

kernel/power/Kconfig
kernel/power/Makefile
kernel/power/consoleearlysuspend.c [new file with mode: 0644]

index a135db5..eec7034 100644 (file)
@@ -59,6 +59,23 @@ config EARLYSUSPEND
          Call early suspend handlers when the user requested sleep state
          changes.
 
+choice
+       prompt "User-space screen access"
+       default CONSOLE_EARLYSUSPEND
+       depends on HAS_EARLYSUSPEND
+
+       config NO_USER_SPACE_SCREEN_ACCESS_CONTROL
+               bool "None"
+
+       config CONSOLE_EARLYSUSPEND
+               bool "Console switch on early-suspend"
+               depends on HAS_EARLYSUSPEND && VT
+               ---help---
+                 Register early suspend handler to perform a console switch to
+                 when user-space should stop drawing to the screen and a switch
+                 back when it should resume.
+endchoice
+
 config HIBERNATE_CALLBACKS
        bool
 
index 44a3db6..0d1c5e4 100644 (file)
@@ -11,5 +11,6 @@ obj-$(CONFIG_HIBERNATION)     += hibernate.o snapshot.o swap.o user.o \
 obj-$(CONFIG_WAKELOCK)         += wakelock.o
 obj-$(CONFIG_USER_WAKELOCK)    += userwakelock.o
 obj-$(CONFIG_EARLYSUSPEND)     += earlysuspend.o
+obj-$(CONFIG_CONSOLE_EARLYSUSPEND)     += consoleearlysuspend.o
 
 obj-$(CONFIG_MAGIC_SYSRQ)      += poweroff.o
diff --git a/kernel/power/consoleearlysuspend.c b/kernel/power/consoleearlysuspend.c
new file mode 100644 (file)
index 0000000..a8befb4
--- /dev/null
@@ -0,0 +1,78 @@
+/* kernel/power/consoleearlysuspend.c
+ *
+ * Copyright (C) 2005-2008 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/console.h>
+#include <linux/earlysuspend.h>
+#include <linux/kbd_kern.h>
+#include <linux/module.h>
+#include <linux/vt_kern.h>
+#include <linux/wait.h>
+
+#define EARLY_SUSPEND_CONSOLE  (MAX_NR_CONSOLES-1)
+
+static int orig_fgconsole;
+static void console_early_suspend(struct early_suspend *h)
+{
+       acquire_console_sem();
+       orig_fgconsole = fg_console;
+       if (vc_allocate(EARLY_SUSPEND_CONSOLE))
+               goto err;
+       if (set_console(EARLY_SUSPEND_CONSOLE))
+               goto err;
+       release_console_sem();
+
+       if (vt_waitactive(EARLY_SUSPEND_CONSOLE))
+               pr_warning("console_early_suspend: Can't switch VCs.\n");
+       return;
+err:
+       pr_warning("console_early_suspend: Can't set console\n");
+       release_console_sem();
+}
+
+static void console_late_resume(struct early_suspend *h)
+{
+       int ret;
+       acquire_console_sem();
+       ret = set_console(orig_fgconsole);
+       release_console_sem();
+       if (ret) {
+               pr_warning("console_late_resume: Can't set console.\n");
+               return;
+       }
+
+       if (vt_waitactive(orig_fgconsole))
+               pr_warning("console_late_resume: Can't switch VCs.\n");
+}
+
+static struct early_suspend console_early_suspend_desc = {
+       .level = EARLY_SUSPEND_LEVEL_STOP_DRAWING,
+       .suspend = console_early_suspend,
+       .resume = console_late_resume,
+};
+
+static int __init console_early_suspend_init(void)
+{
+       register_early_suspend(&console_early_suspend_desc);
+       return 0;
+}
+
+static void  __exit console_early_suspend_exit(void)
+{
+       unregister_early_suspend(&console_early_suspend_desc);
+}
+
+module_init(console_early_suspend_init);
+module_exit(console_early_suspend_exit);
+