power management: change /sys/power/disk display

Change /sys/power/disk to display all valid modes as well as the currently
selected one in a fashion known from the LED subsystem.

This changes userspace API, but it is apparently not used much (we asked
some userspace developers)

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 28 insertions, 1 deletions

diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index e518379b667a..06331374d862 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -350,7 +350,34 @@ static const char * const pm_disk_modes[] = {
 
 static ssize_t disk_show(struct kset *kset, char *buf)
 {
-        return sprintf(buf, "%s\n", pm_disk_modes[pm_disk_mode]);
+        int i;
+        char *start = buf;
+
+        for (i = PM_DISK_PLATFORM; i < PM_DISK_MAX; i++) {
+                if (!pm_disk_modes[i])
+                        continue;
+                switch (i) {
+                case PM_DISK_SHUTDOWN:
+                case PM_DISK_REBOOT:
+                case PM_DISK_TEST:
+                case PM_DISK_TESTPROC:
+                        break;
+                default:
+                        if (pm_ops && pm_ops->enter &&
+                            (i == pm_ops->pm_disk_mode))
+                                break;
+                        /* not a valid mode, continue with loop */
+                        continue;
+                }
+                if (i == pm_disk_mode)
+                        buf += sprintf(buf, "[%s]", pm_disk_modes[i]);
+                else
+                        buf += sprintf(buf, "%s", pm_disk_modes[i]);
+                if (i+1 != PM_DISK_MAX)
+                        buf += sprintf(buf, " ");
+        }
+        buf += sprintf(buf, "\n");
+        return buf-start;
 }