From: Johannes Berg 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 Acked-by: "Rafael J. Wysocki" Acked-by: Pavel Machek Signed-off-by: Andrew Morton --- Documentation/power/interface.txt | 8 +++++-- kernel/power/disk.c | 29 +++++++++++++++++++++++++++- 2 files changed, 34 insertions(+), 3 deletions(-) diff -puN Documentation/power/interface.txt~power-management-change-sys-power-disk-display Documentation/power/interface.txt --- a/Documentation/power/interface.txt~power-management-change-sys-power-disk-display +++ a/Documentation/power/interface.txt @@ -34,8 +34,12 @@ for 5 seconds, resume devices, unfreeze we are able to look in the log messages and work out, for example, which code is being slow and which device drivers are misbehaving. -Reading from this file will display what the mode is currently set -to. Writing to this file will accept one of +Reading from this file will display all supported modes and the currently +selected one in brackets, for example + + [shutdown] reboot test testproc + +Writing to this file will accept one of 'platform' (only if the platform supports it) 'shutdown' diff -puN kernel/power/disk.c~power-management-change-sys-power-disk-display kernel/power/disk.c --- a/kernel/power/disk.c~power-management-change-sys-power-disk-display +++ a/kernel/power/disk.c @@ -350,7 +350,34 @@ static const char * const pm_disk_modes[ static ssize_t disk_show(struct subsystem * subsys, 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; } _