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 <[email protected]>
--
drivers/rtc/Kconfig | 11 ++++
drivers/rtc/Makefile | 2
drivers/rtc/rtc-sysfs.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 122 insertions(+), 1 deletion(-)
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-rtc/drivers/rtc/rtc-sysfs.c 2006-02-13 19:35:30.000000000 +0100
@@ -0,0 +1,110 @@
+/*
+ * RTC subsystem, sysfs interface
+ *
+ * Copyright (C) 2005 Tower Technologies
+ * Author: Alessandro Zummo <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+*/
+
+#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 = -ENODEV;
+ struct rtc_time tm;
+
+ if ((retval = rtc_read_time(dev, &tm)) == 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 = -ENODEV;
+ struct rtc_time tm;
+
+ if ((retval = rtc_read_time(dev, &tm)) == 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 = -ENODEV;
+ struct rtc_time tm;
+
+ if ((retval = rtc_read_time(dev, &tm)) == 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);
+
+/* insertion/removal hooks */
+
+static int __devinit rtc_sysfs_add_device(struct class_device *class_dev,
+ struct class_interface *class_intf)
+{
+ class_device_create_file(class_dev, &class_device_attr_name);
+ class_device_create_file(class_dev, &class_device_attr_date);
+ class_device_create_file(class_dev, &class_device_attr_time);
+ class_device_create_file(class_dev, &class_device_attr_since_epoch);
+ dev_info(class_dev->dev, "rtc intf: sysfs\n");
+ return 0;
+}
+
+static void rtc_sysfs_remove_device(struct class_device *class_dev,
+ struct class_interface *class_intf)
+{
+ class_device_remove_file(class_dev, &class_device_attr_name);
+ class_device_remove_file(class_dev, &class_device_attr_date);
+ class_device_remove_file(class_dev, &class_device_attr_time);
+ class_device_remove_file(class_dev, &class_device_attr_since_epoch);
+}
+
+/* interface registration */
+
+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 <[email protected]>");
+MODULE_DESCRIPTION("RTC class sysfs interface");
+MODULE_LICENSE("GPL");
--- linux-rtc.orig/drivers/rtc/Kconfig 2006-02-13 19:35:30.000000000 +0100
+++ linux-rtc/drivers/rtc/Kconfig 2006-02-13 19:39:58.000000000 +0100
@@ -36,6 +36,17 @@ 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 2006-02-13 19:35:30.000000000 +0100
+++ linux-rtc/drivers/rtc/Makefile 2006-02-13 19:39:58.000000000 +0100
@@ -6,4 +6,4 @@ obj-y += utils.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
--
Hi Alessandro,
On Monday 13 February 2006 17:54, Alessandro Zummo wrote:
> +static ssize_t rtc_sysfs_show_date(struct class_device *dev, char *buf)
> +{
> + ssize_t retval = -ENODEV;
> + struct rtc_time tm;
> +
> + if ((retval = rtc_read_time(dev, &tm)) == 0) {
Retval is set unconditionally here so there is no point in initializing
it to -ENODEV above.
> + 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 = -ENODEV;
> + struct rtc_time tm;
> +
> + if ((retval = rtc_read_time(dev, &tm)) == 0) {
Same here.
> + 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 = -ENODEV;
> + struct rtc_time tm;
> +
> + if ((retval = rtc_read_time(dev, &tm)) == 0) {
And here.
> + 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);
> +
> +/* insertion/removal hooks */
> +
> +static int __devinit rtc_sysfs_add_device(struct class_device *class_dev,
> + struct class_interface *class_intf)
> +{
> + class_device_create_file(class_dev, &class_device_attr_name);
> + class_device_create_file(class_dev, &class_device_attr_date);
> + class_device_create_file(class_dev, &class_device_attr_time);
> + class_device_create_file(class_dev, &class_device_attr_since_epoch);
Maybe using attribute group here will help and also allow easier error
hanling?
--
Dmitry
On Mon, 13 Feb 2006 22:47:17 -0500
Dmitry Torokhov <[email protected]> wrote:
> > + struct rtc_time tm;
> > +
> > + if ((retval = rtc_read_time(dev, &tm)) == 0) {
>
> Retval is set unconditionally here so there is no point in initializing
> it to -ENODEV above.
> > +static int __devinit rtc_sysfs_add_device(struct class_device *class_dev,
> > + struct class_interface *class_intf)
> > +{
> > + class_device_create_file(class_dev, &class_device_attr_name);
> > + class_device_create_file(class_dev, &class_device_attr_date);
> > + class_device_create_file(class_dev, &class_device_attr_time);
> > + class_device_create_file(class_dev, &class_device_attr_since_epoch);
>
> Maybe using attribute group here will help and also allow easier error
> hanling?
done, thanks.
--
Best regards,
Alessandro Zummo,
Tower Technologies - Turin, Italy
http://www.towertech.it