2006-01-09 00:47:08

by Alessandro Zummo

[permalink] [raw]
Subject: [PATCH 4/8] RTC subsystem, proc interface

This patch adds the proc interface to the
RTC subsystem.

The first RTC driver which registers with
the class will be accessible by /proc/driver/rtc .

Signed-off-by: Alessandro Zummo <[email protected]>
--

drivers/rtc/Kconfig | 11 +++
drivers/rtc/Makefile | 1
drivers/rtc/rtc-proc.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 170 insertions(+)

--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-nslu2/drivers/rtc/rtc-proc.c 2006-01-04 01:27:14.000000000 +0100
@@ -0,0 +1,158 @@
+/*
+ * RTC subsystem, proc interface
+ *
+ * Copyright (C) 2005 Tower Technologies
+ * Author: Alessandro Zummo <[email protected]>
+ *
+ * based on arch/arm/common/rtctime.c
+ *
+ * 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>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+static struct class_device *rtc_dev = NULL;
+static DECLARE_MUTEX(rtc_sem);
+
+static int rtc_proc_show(struct seq_file *seq, void *offset)
+{
+ struct class_device *class_dev = seq->private;
+ struct rtc_class_ops *ops = to_rtc_device(class_dev)->ops;
+ struct rtc_wkalrm alrm;
+ struct rtc_time tm;
+
+ if (rtc_read_time(class_dev, &tm) == 0) {
+ seq_printf(seq,
+ "rtc_time\t: %02d:%02d:%02d\n"
+ "rtc_date\t: %04d-%02d-%02d\n",
+ tm.tm_hour, tm.tm_min, tm.tm_sec,
+ tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+ }
+
+ if (rtc_read_alarm(class_dev, &alrm) == 0) {
+ seq_printf(seq, "alrm_time\t: ");
+ if ((unsigned int)alrm.time.tm_hour <= 24)
+ seq_printf(seq, "%02d:", alrm.time.tm_hour);
+ else
+ seq_printf(seq, "**:");
+ if ((unsigned int)alrm.time.tm_min <= 59)
+ seq_printf(seq, "%02d:", alrm.time.tm_min);
+ else
+ seq_printf(seq, "**:");
+ if ((unsigned int)alrm.time.tm_sec <= 59)
+ seq_printf(seq, "%02d\n", alrm.time.tm_sec);
+ else
+ seq_printf(seq, "**\n");
+
+ seq_printf(seq, "alrm_date\t: ");
+ if ((unsigned int)alrm.time.tm_year <= 200)
+ seq_printf(seq, "%04d-", alrm.time.tm_year + 1900);
+ else
+ seq_printf(seq, "****-");
+ if ((unsigned int)alrm.time.tm_mon <= 11)
+ seq_printf(seq, "%02d-", alrm.time.tm_mon + 1);
+ else
+ seq_printf(seq, "**-");
+ if ((unsigned int)alrm.time.tm_mday <= 31)
+ seq_printf(seq, "%02d\n", alrm.time.tm_mday);
+ else
+ seq_printf(seq, "**\n");
+ seq_printf(seq, "alrm_wakeup\t: %s\n",
+ alrm.enabled ? "yes" : "no");
+ seq_printf(seq, "alrm_pending\t: %s\n",
+ alrm.pending ? "yes" : "no");
+ }
+
+ if (ops->proc)
+ ops->proc(class_dev->dev, seq);
+
+ return 0;
+}
+
+static int rtc_proc_open(struct inode *inode, struct file *file)
+{
+ struct class_device *class_dev = PDE(inode)->data;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ return single_open(file, rtc_proc_show, class_dev);
+}
+
+static int rtc_proc_release(struct inode *inode, struct file *file)
+{
+ int res = single_release(inode, file);
+ module_put(THIS_MODULE);
+ return res;
+}
+
+static struct file_operations rtc_proc_fops = {
+ .open = rtc_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = rtc_proc_release,
+};
+
+static int rtc_proc_add_device(struct class_device *class_dev,
+ struct class_interface *class_intf)
+{
+ down(&rtc_sem);
+ if (rtc_dev == NULL) {
+ struct proc_dir_entry *ent;
+
+ rtc_dev = class_dev;
+
+ if ((ent = create_proc_entry("driver/rtc", 0, NULL))) {
+ struct rtc_device *rtc = to_rtc_device(class_dev);
+
+ ent->proc_fops = &rtc_proc_fops;
+ ent->owner = rtc->owner;
+ ent->data = class_dev;
+
+ dev_info(class_dev->dev, "rtc intf: proc\n");
+ }
+ else
+ rtc_dev = NULL;
+ }
+ up(&rtc_sem);
+
+ return 0;
+}
+
+static void rtc_proc_remove_device(struct class_device *class_dev,
+ struct class_interface *class_intf)
+{
+ down(&rtc_sem);
+ if (rtc_dev == class_dev) {
+ remove_proc_entry("driver/rtc", NULL);
+ rtc_dev = NULL;
+ }
+ up(&rtc_sem);
+}
+
+struct class_interface rtc_proc_interface = {
+ .add = &rtc_proc_add_device,
+ .remove = &rtc_proc_remove_device,
+};
+
+static int __init rtc_proc_init(void)
+{
+ return rtc_interface_register(&rtc_proc_interface);
+}
+
+static void __exit rtc_proc_exit(void)
+{
+ class_interface_unregister(&rtc_proc_interface);
+}
+
+module_init(rtc_proc_init);
+module_exit(rtc_proc_exit);
+
+MODULE_AUTHOR("Alessandro Zummo <[email protected]>");
+MODULE_DESCRIPTION("RTC class proc interface");
+MODULE_LICENSE("GPL");
--- linux-nslu2.orig/drivers/rtc/Kconfig 2006-01-04 01:27:12.000000000 +0100
+++ linux-nslu2/drivers/rtc/Kconfig 2006-01-04 01:27:14.000000000 +0100
@@ -30,6 +30,17 @@ config RTC_INTF_SYSFS
This driver can also be built as a module. If so, the module
will be called rtc-sysfs.

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

--- linux-nslu2.orig/drivers/rtc/Makefile 2006-01-04 01:27:12.000000000 +0100
+++ linux-nslu2/drivers/rtc/Makefile 2006-01-04 01:27:14.000000000 +0100
@@ -6,3 +6,4 @@ obj-y += utils.o
obj-$(CONFIG_RTC_CLASS) += rtc-core.o
rtc-core-y := class.o interface.o
obj-$(CONFIG_RTC_INTF_SYSFS) += rtc-sysfs.o
+obj-$(CONFIG_RTC_INTF_PROC) += rtc-proc.o

--


2006-01-09 02:04:04

by Alessandro Zummo

[permalink] [raw]
Subject: Re: [PATCH 4/8] RTC subsystem, proc interface

On Sun, 8 Jan 2006 20:56:29 -0500
Dmitry Torokhov <[email protected]> wrote:

> > +static void rtc_proc_remove_device(struct class_device *class_dev,
> > +??????????????????????????????????????? ? ? ?struct class_interface *class_intf)
> > +{
> > +???????down(&rtc_sem);
> > +???????if (rtc_dev == class_dev) {
> > +???????????????remove_proc_entry("driver/rtc", NULL);
> > +???????????????rtc_dev = NULL;
> > +???????}
> > +???????up(&rtc_sem);
> > +}
>
> What if I happen to remove (unregister) rtc devices in order other
> than they were registered in? You need a counter there instead of
> storing the first device created.

Only the first device that registers will get the /proc/driver/rtc
entry, which will be removed when the driver unregisters.

/proc/driver/rtc is a legacy interface, thus supporting it
for more than one RTC is useless. Any system that uses
more than one RTCs should access them via /dev/rtcX or
via sysfs.


--

Best regards,

Alessandro Zummo,
Tower Technologies - Turin, Italy

http://www.towertech.it

2006-01-09 02:50:59

by Dmitry Torokhov

[permalink] [raw]
Subject: Re: [PATCH 4/8] RTC subsystem, proc interface

On Sunday 08 January 2006 21:04, Alessandro Zummo wrote:
> On Sun, 8 Jan 2006 20:56:29 -0500
> Dmitry Torokhov <[email protected]> wrote:
>
> > > +static void rtc_proc_remove_device(struct class_device *class_dev,
> > > +??????????????????????????????????????? ? ? ?struct class_interface *class_intf)
> > > +{
> > > +???????down(&rtc_sem);
> > > +???????if (rtc_dev == class_dev) {
> > > +???????????????remove_proc_entry("driver/rtc", NULL);
> > > +???????????????rtc_dev = NULL;
> > > +???????}
> > > +???????up(&rtc_sem);
> > > +}
> >
> > What if I happen to remove (unregister) rtc devices in order other
> > than they were registered in? You need a counter there instead of
> > storing the first device created.
>
> Only the first device that registers will get the /proc/driver/rtc
> entry, which will be removed when the driver unregisters.
>
> /proc/driver/rtc is a legacy interface, thus supporting it
> for more than one RTC is useless. Any system that uses
> more than one RTCs should access them via /dev/rtcX or
> via sysfs.
>

Oh, I see. Ignore me then...

--
Dmitry