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authorDavid Fries <david@fries.net>2012-10-04 17:14:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-06 03:05:04 +0900
commit4c24e29e65843ed912c14cdc293ed922e33efdcc (patch)
tree876a8cac65c0a8200fbed589a1ba3a1c11bf6643 /drivers/rtc
parentbe8b6d510072461b50958527e7b157f53e5388d7 (diff)
downloadlwn-4c24e29e65843ed912c14cdc293ed922e33efdcc.tar.gz
lwn-4c24e29e65843ed912c14cdc293ed922e33efdcc.zip
rtc_sysfs_show_hctosys(): display 0 if resume failed
Without this patch /sys/class/rtc/$CONFIG_RTC_HCTOSYS_DEVICE/hctosys contains a 1 (meaning "This rtc was used to initialize the system clock") even if setting the time by do_settimeofday() at bootup failed. The RTC can also be used to set the clock on resume, if it did 1, otherwise 0. Previously there was no indication if the RTC was used to set the clock in resume. This uses only CONFIG_RTC_HCTOSYS_DEVICE for conditional compilation instead of it and CONFIG_RTC_HCTOSYS to be more consistent. rtc_hctosys_ret was moved to class.c so class.c no longer depends on hctosys.c. [sfr@canb.auug.org.au: fix build] Signed-off-by: David Fries <David@Fries.net> Cc: Matthew Garrett <mjg@redhat.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/class.c8
-rw-r--r--drivers/rtc/hctosys.c4
-rw-r--r--drivers/rtc/rtc-sysfs.c6
3 files changed, 14 insertions, 4 deletions
diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 37b1d82fda08..f8a0aab218cb 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -31,8 +31,12 @@ static void rtc_device_release(struct device *dev)
kfree(rtc);
}
-#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
+#ifdef CONFIG_RTC_HCTOSYS_DEVICE
+/* Result of the last RTC to system clock attempt. */
+int rtc_hctosys_ret = -ENODEV;
+#endif
+#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
/*
* On suspend(), measure the delta between one RTC and the
* system's wall clock; restore it on resume().
@@ -84,6 +88,7 @@ static int rtc_resume(struct device *dev)
struct timespec new_system, new_rtc;
struct timespec sleep_time;
+ rtc_hctosys_ret = -ENODEV;
if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
return 0;
@@ -117,6 +122,7 @@ static int rtc_resume(struct device *dev)
if (sleep_time.tv_sec >= 0)
timekeeping_inject_sleeptime(&sleep_time);
+ rtc_hctosys_ret = 0;
return 0;
}
diff --git a/drivers/rtc/hctosys.c b/drivers/rtc/hctosys.c
index bc90b091f195..4aa60d74004e 100644
--- a/drivers/rtc/hctosys.c
+++ b/drivers/rtc/hctosys.c
@@ -22,8 +22,6 @@
* the best guess is to add 0.5s.
*/
-int rtc_hctosys_ret = -ENODEV;
-
static int __init rtc_hctosys(void)
{
int err = -ENODEV;
@@ -56,7 +54,7 @@ static int __init rtc_hctosys(void)
rtc_tm_to_time(&tm, &tv.tv_sec);
- do_settimeofday(&tv);
+ err = do_settimeofday(&tv);
dev_info(rtc->dev.parent,
"setting system clock to "
diff --git a/drivers/rtc/rtc-sysfs.c b/drivers/rtc/rtc-sysfs.c
index 380083ca572f..b70e2bb63645 100644
--- a/drivers/rtc/rtc-sysfs.c
+++ b/drivers/rtc/rtc-sysfs.c
@@ -102,6 +102,12 @@ rtc_sysfs_set_max_user_freq(struct device *dev, struct device_attribute *attr,
return n;
}
+/**
+ * rtc_sysfs_show_hctosys - indicate if the given RTC set the system time
+ *
+ * Returns 1 if the system clock was set by this RTC at the last
+ * boot or resume event.
+ */
static ssize_t
rtc_sysfs_show_hctosys(struct device *dev, struct device_attribute *attr,
char *buf)