[PATCH 08/18] RTC subsystem, sysfs interface

Alessandro Zummo
2006-03-18T17:22:23Z

[-- Attachment #1: rtc-intf-sysfs.patch --]
[-- Type: text/plain, Size: 4744 bytes --]

This patch adds the sysfs interface to the
RTC subsystem.

Each RTC client will have his own entry
under /sys/classs/rtc/rtcN .

Within this entry some attributes are
exported by the subsystem, like date and time.

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
--

drivers/rtc/Kconfig | 11 ++++
drivers/rtc/Makefile | 3 +
drivers/rtc/rtc-sysfs.c | 124 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+)

--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-rtc/drivers/rtc/rtc-sysfs.c 2006-03-13 03:27:33.000000000 +0100
@@ -0,0 +1,124 @@
+/*
+ * RTC subsystem, sysfs interface
+ *
+ * Copyright (C) 2005 Tower Technologies
+ * Author: Alessandro Zummo <a.zummo@towertech.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/module.h>
+#include <linux/rtc.h>
+
+/* device attributes */
+
+static ssize_t rtc_sysfs_show_name(struct class_device *dev, char *buf)
+{
+ return sprintf(buf, "%s\n", to_rtc_device(dev)->name);
+}
+static CLASS_DEVICE_ATTR(name, S_IRUGO, rtc_sysfs_show_name, NULL);
+
+static ssize_t rtc_sysfs_show_date(struct class_device *dev, char *buf)
+{
+ ssize_t retval;
+ struct rtc_time tm;
+
+ retval = rtc_read_time(dev, &tm);
+ if (retval == 0) {
+ retval = sprintf(buf, "%04d-%02d-%02d\n",
+ tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+ }
+
+ return retval;
+}
+static CLASS_DEVICE_ATTR(date, S_IRUGO, rtc_sysfs_show_date, NULL);
+
+static ssize_t rtc_sysfs_show_time(struct class_device *dev, char *buf)
+{
+ ssize_t retval;
+ struct rtc_time tm;
+
+ retval = rtc_read_time(dev, &tm);
+ if (retval == 0) {
+ retval = sprintf(buf, "%02d:%02d:%02d\n",
+ tm.tm_hour, tm.tm_min, tm.tm_sec);
+ }
+
+ return retval;
+}
+static CLASS_DEVICE_ATTR(time, S_IRUGO, rtc_sysfs_show_time, NULL);
+
+static ssize_t rtc_sysfs_show_since_epoch(struct class_device *dev, char *buf)
+{
+ ssize_t retval;
+ struct rtc_time tm;
+
+ retval = rtc_read_time(dev, &tm);
+ if (retval == 0) {
+ unsigned long time;
+ rtc_tm_to_time(&tm, &time);
+ retval = sprintf(buf, "%lu\n", time);
+ }
+
+ return retval;
+}
+static CLASS_DEVICE_ATTR(since_epoch, S_IRUGO, rtc_sysfs_show_since_epoch, NULL);
+
+static struct attribute *rtc_attrs[] = {
+ &class_device_attr_name.attr,
+ &class_device_attr_date.attr,
+ &class_device_attr_time.attr,
+ &class_device_attr_since_epoch.attr,
+ NULL,
+};
+
+static struct attribute_group rtc_attr_group = {
+ .attrs = rtc_attrs,
+};
+
+static int __devinit rtc_sysfs_add_device(struct class_device *class_dev,
+ struct class_interface *class_intf)
+{
+ int err;
+
+ dev_info(class_dev->dev, "rtc intf: sysfs\n");
+
+ err = sysfs_create_group(&class_dev->kobj, &rtc_attr_group);
+ if (err)
+ dev_err(class_dev->dev,
+ "failed to create sysfs attributes\n");
+
+ return err;
+}
+
+static void rtc_sysfs_remove_device(struct class_device *class_dev,
+ struct class_interface *class_intf)
+{
+ sysfs_remove_group(&class_dev->kobj, &rtc_attr_group);
+}
+
+/* interface registration */
+
+static struct class_interface rtc_sysfs_interface = {
+ .add = &rtc_sysfs_add_device,
+ .remove = &rtc_sysfs_remove_device,
+};
+
+static int __init rtc_sysfs_init(void)
+{
+ return rtc_interface_register(&rtc_sysfs_interface);
+}
+
+static void __exit rtc_sysfs_exit(void)
+{
+ class_interface_unregister(&rtc_sysfs_interface);
+}
+
+module_init(rtc_sysfs_init);
+module_exit(rtc_sysfs_exit);
+
+MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
+MODULE_DESCRIPTION("RTC class sysfs interface");
+MODULE_LICENSE("GPL");
--- linux-rtc.orig/drivers/rtc/Kconfig 2006-03-13 03:26:41.000000000 +0100
+++ linux-rtc/drivers/rtc/Kconfig 2006-03-13 03:27:22.000000000 +0100
@@ -40,6 +40,17 @@ config RTC_HCTOSYS_DEVICE
comment "RTC interfaces"
depends on RTC_CLASS

+config RTC_INTF_SYSFS
+ tristate "sysfs"
+ depends on RTC_CLASS && SYSFS
+ default RTC_CLASS
+ help
+ Say yes here if you want to use your RTC using the sysfs
+ interface, /sys/class/rtc/rtcX .
+
+ This driver can also be built as a module. If so, the module
+ will be called rtc-sysfs.
+
comment "RTC drivers"
depends on RTC_CLASS

--- linux-rtc.orig/drivers/rtc/Makefile 2006-03-13 03:26:41.000000000 +0100
+++ linux-rtc/drivers/rtc/Makefile 2006-03-13 03:27:22.000000000 +0100
@@ -6,3 +6,6 @@ obj-$(CONFIG_RTC_LIB) += rtc-lib.o
obj-$(CONFIG_RTC_HCTOSYS) += hctosys.o
obj-$(CONFIG_RTC_CLASS) += rtc-core.o
rtc-core-y := class.o interface.o
+
+obj-$(CONFIG_RTC_INTF_SYSFS) += rtc-sysfs.o
+

--