From 92589c986b3360ce15d239fd5113a856412a0b3f Mon Sep 17 00:00:00 2001 From: "Kim, Milo" Date: Thu, 4 Oct 2012 17:13:45 -0700 Subject: [PATCH] rtc-proc: permit the /proc/driver/rtc device to use other devices To get time information via /proc/driver/rtc, only the first device (rtc0) is used. If the rtcN (eg. rtc1 or rtc2) is used for the system clock, there is no way to get information of rtcN via /proc/driver/rtc. With this patch, the time data can be retrieved from the system clock RTC. If the RTC_HCTOSYS_DEVICE is not defined, then rtc0 is used by default. Signed-off-by: Milo(Woogyom) Kim Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/rtc.txt | 5 +++-- drivers/rtc/Kconfig | 10 ++++++---- drivers/rtc/rtc-proc.c | 24 ++++++++++++++++++++++-- 3 files changed, 31 insertions(+), 8 deletions(-) diff --git a/Documentation/rtc.txt b/Documentation/rtc.txt index 250160469d8..32aa4002de4 100644 --- a/Documentation/rtc.txt +++ b/Documentation/rtc.txt @@ -119,8 +119,9 @@ three different userspace interfaces: * /sys/class/rtc/rtcN ... sysfs attributes support readonly access to some RTC attributes. - * /proc/driver/rtc ... the first RTC (rtc0) may expose itself - using a procfs interface. More information is (currently) shown + * /proc/driver/rtc ... the system clock RTC may expose itself + using a procfs interface. If there is no RTC for the system clock, + rtc0 is used by default. More information is (currently) shown here than through sysfs. The RTC Class framework supports a wide variety of RTCs, ranging from those diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index fabc99a75c6..a4a805c273b 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -69,13 +69,15 @@ config RTC_INTF_SYSFS If unsure, say Y. config RTC_INTF_PROC - boolean "/proc/driver/rtc (procfs for rtc0)" + boolean "/proc/driver/rtc (procfs for rtcN)" depends on PROC_FS default RTC_CLASS help - Say yes here if you want to use your first RTC through the proc - interface, /proc/driver/rtc. Other RTCs will not be available - through that API. + Say yes here if you want to use your system clock RTC through + the proc interface, /proc/driver/rtc. + Other RTCs will not be available through that API. + If there is no RTC for the system clock, then the first RTC(rtc0) + is used by default. If unsure, say Y. diff --git a/drivers/rtc/rtc-proc.c b/drivers/rtc/rtc-proc.c index 0a59fda5c09..e96236ac2e7 100644 --- a/drivers/rtc/rtc-proc.c +++ b/drivers/rtc/rtc-proc.c @@ -18,6 +18,26 @@ #include "rtc-core.h" +#define NAME_SIZE 10 + +#if defined(CONFIG_RTC_HCTOSYS_DEVICE) +static bool is_rtc_hctosys(struct rtc_device *rtc) +{ + int size; + char name[NAME_SIZE]; + + size = scnprintf(name, NAME_SIZE, "rtc%d", rtc->id); + if (size > NAME_SIZE) + return false; + + return !strncmp(name, CONFIG_RTC_HCTOSYS_DEVICE, NAME_SIZE); +} +#else +static bool is_rtc_hctosys(struct rtc_device *rtc) +{ + return (rtc->id == 0); +} +#endif static int rtc_proc_show(struct seq_file *seq, void *offset) { @@ -117,12 +137,12 @@ static const struct file_operations rtc_proc_fops = { void rtc_proc_add_device(struct rtc_device *rtc) { - if (rtc->id == 0) + if (is_rtc_hctosys(rtc)) proc_create_data("driver/rtc", 0, NULL, &rtc_proc_fops, rtc); } void rtc_proc_del_device(struct rtc_device *rtc) { - if (rtc->id == 0) + if (is_rtc_hctosys(rtc)) remove_proc_entry("driver/rtc", NULL); }