PM / Hibernate: Add resumedelay kernel param in addition to resumewait

Patch "PM / Hibernate: Add resumewait param to support MMC-like
devices as resume file" added the resumewait kernel command line
option.  The present patch adds resumedelay so that
resumewait/delay were analogous to rootwait/delay.

[rjw: Modified the subject and changelog slightly.]

Signed-off-by: Barry Song <baohua.song@csr.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

2 files changed, 17 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 88a7b197a4eb..831bde222bde 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2240,6 +2240,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         in <PAGE_SIZE> units (needed only for swap files).
                         See  Documentation/power/swsusp-and-swap-files.txt
 
+        resumedelay=    [HIBERNATION] Delay (in seconds) to pause before attempting to
+                        read the resume files
+
         resumewait      [HIBERNATION] Wait (indefinitely) for resume device to show up.
                         Useful for devices that are detected asynchronously
                         (e.g. USB and MMC devices).
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 0f8785080cde..50f537953e70 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -33,6 +33,7 @@
 static int nocompress = 0;
 static int noresume = 0;
 static int resume_wait = 0;
+static int resume_delay = 0;
 static char resume_file[256] = CONFIG_PM_STD_PARTITION;
 dev_t swsusp_resume_device;
 sector_t swsusp_resume_block;
@@ -730,6 +731,12 @@ static int software_resume(void)
 
         pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
 
+        if (resume_delay) {
+                printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
+                        resume_delay);
+                ssleep(resume_delay);
+        }
+
         /* Check if the device is there */
         swsusp_resume_device = name_to_dev_t(resume_file);
         if (!swsusp_resume_device) {
@@ -1079,8 +1086,15 @@ static int __init resumewait_setup(char *str)
         return 1;
 }
 
+static int __init resumedelay_setup(char *str)
+{
+        resume_delay = simple_strtoul(str, NULL, 0);
+        return 1;
+}
+
 __setup("noresume", noresume_setup);
 __setup("resume_offset=", resume_offset_setup);
 __setup("resume=", resume_setup);
 __setup("hibernate=", hibernate_setup);
 __setup("resumewait", resumewait_setup);
+__setup("resumedelay=", resumedelay_setup);