hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

rtc: add max_user_freq to sysfs 

drivers/char/rtc.c exposed a sysctl to change the maximum frequency at
which a non-root user could ask the RTC to generate interrupts (via the
RTC_IRQP_SET ioctl).  This value is no longer available under the new RTC
subsystem, so add it to sysfs for each RTC device.

Works for me on x86_64 (both reads and writes), using rtc-cmos.

Signed-off-by: Bryan Kadzban <bryan@kdzbn.homelinux.net>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Bryan Kadzban 2007-10-16 01:28:22 -07:00 committed by Linus Torvalds
parent 05440dfcfc
commit 06c65eb455
1 changed files with 24 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
drivers/rtc/rtc-sysfs.c
View File

@ -73,11 +73,35 @@ rtc_sysfs_show_since_epoch(struct device *dev, struct device_attribute *attr,
return retval;
}
static ssize_t
rtc_sysfs_show_max_user_freq(struct device *dev, struct device_attribute *attr,
char *buf)
{
return sprintf(buf, "%d\n", to_rtc_device(dev)->max_user_freq);
}
static ssize_t
rtc_sysfs_set_max_user_freq(struct device *dev, struct device_attribute *attr,
const char *buf, size_t n)
{
struct rtc_device *rtc = to_rtc_device(dev);
unsigned long val = simple_strtoul(buf, NULL, 0);
if (val >= 4096 || val == 0)
return -EINVAL;
rtc->max_user_freq = (int)val;
return n;
}
static struct device_attribute rtc_attrs[] = {
__ATTR(name, S_IRUGO, rtc_sysfs_show_name, NULL),
__ATTR(date, S_IRUGO, rtc_sysfs_show_date, NULL),
__ATTR(time, S_IRUGO, rtc_sysfs_show_time, NULL),
__ATTR(since_epoch, S_IRUGO, rtc_sysfs_show_since_epoch, NULL),
__ATTR(max_user_freq, S_IRUGO | S_IWUSR, rtc_sysfs_show_max_user_freq,
rtc_sysfs_set_max_user_freq),
{ },
};