X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Frtc%2Frtc-sysfs.c;h=2531ce4c9db082d94cd3b1afba7ac7f4acf93f85;hb=9470565579f29486f4ed0ffa50774268b64994b0;hp=97444b45cc26e08b2d898db4bf71daea23822d37;hpb=ab6a2d70d18edc7a716ef3127b9e13382faec98c;p=safe%2Fjmp%2Flinux-2.6 diff --git a/drivers/rtc/rtc-sysfs.c b/drivers/rtc/rtc-sysfs.c index 97444b4..2531ce4 100644 --- a/drivers/rtc/rtc-sysfs.c +++ b/drivers/rtc/rtc-sysfs.c @@ -17,13 +17,23 @@ /* device attributes */ -static ssize_t rtc_sysfs_show_name(struct class_device *dev, char *buf) +/* + * NOTE: RTC times displayed in sysfs use the RTC's timezone. That's + * ideally UTC. However, PCs that also boot to MS-Windows normally use + * the local time and change to match daylight savings time. That affects + * attributes including date, time, since_epoch, and wakealarm. + */ + +static ssize_t +rtc_sysfs_show_name(struct device *dev, struct device_attribute *attr, + 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) +static ssize_t +rtc_sysfs_show_date(struct device *dev, struct device_attribute *attr, + char *buf) { ssize_t retval; struct rtc_time tm; @@ -36,9 +46,10 @@ static ssize_t rtc_sysfs_show_date(struct class_device *dev, char *buf) 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) +static ssize_t +rtc_sysfs_show_time(struct device *dev, struct device_attribute *attr, + char *buf) { ssize_t retval; struct rtc_time tm; @@ -51,9 +62,10 @@ static ssize_t rtc_sysfs_show_time(struct class_device *dev, char *buf) 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) +static ssize_t +rtc_sysfs_show_since_epoch(struct device *dev, struct device_attribute *attr, + char *buf) { ssize_t retval; struct rtc_time tm; @@ -67,35 +79,54 @@ static ssize_t rtc_sysfs_show_since_epoch(struct class_device *dev, char *buf) 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 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), + { }, +}; static ssize_t -rtc_sysfs_show_wakealarm(struct class_device *dev, char *buf) +rtc_sysfs_show_wakealarm(struct device *dev, struct device_attribute *attr, + char *buf) { ssize_t retval; unsigned long alarm; struct rtc_wkalrm alm; - /* Don't show disabled alarms; but the RTC could leave the - * alarm enabled after it's already triggered. Alarms are - * conceptually one-shot, even though some common hardware - * (PCs) doesn't actually work that way. + /* Don't show disabled alarms. For uniformity, RTC alarms are + * conceptually one-shot, even though some common RTCs (on PCs) + * don't actually work that way. * - * REVISIT maybe we should require RTC implementations to - * disable the RTC alarm after it triggers, for uniformity. + * NOTE: RTC implementations where the alarm doesn't match an + * exact YYYY-MM-DD HH:MM[:SS] date *must* disable their RTC + * alarms after they trigger, to ensure one-shot semantics. */ retval = rtc_read_alarm(to_rtc_device(dev), &alm); if (retval == 0 && alm.enabled) { @@ -107,12 +138,15 @@ rtc_sysfs_show_wakealarm(struct class_device *dev, char *buf) } static ssize_t -rtc_sysfs_set_wakealarm(struct class_device *dev, const char *buf, size_t n) +rtc_sysfs_set_wakealarm(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) { ssize_t retval; unsigned long now, alarm; struct rtc_wkalrm alm; struct rtc_device *rtc = to_rtc_device(dev); + char *buf_ptr; + int adjust = 0; /* Only request alarms that trigger in the future. Disable them * by writing another time, e.g. 0 meaning Jan 1 1970 UTC. @@ -122,7 +156,15 @@ rtc_sysfs_set_wakealarm(struct class_device *dev, const char *buf, size_t n) return retval; rtc_tm_to_time(&alm.time, &now); - alarm = simple_strtoul(buf, NULL, 0); + buf_ptr = (char *)buf; + if (*buf_ptr == '+') { + buf_ptr++; + adjust = 1; + } + alarm = simple_strtoul(buf_ptr, NULL, 0); + if (adjust) { + alarm += now; + } if (alarm > now) { /* Avoid accidentally clobbering active alarms; we can't * entirely prevent that here, without even the minimal @@ -148,7 +190,7 @@ rtc_sysfs_set_wakealarm(struct class_device *dev, const char *buf, size_t n) retval = rtc_set_alarm(rtc, &alm); return (retval < 0) ? retval : n; } -static const CLASS_DEVICE_ATTR(wakealarm, S_IRUGO | S_IWUSR, +static DEVICE_ATTR(wakealarm, S_IRUGO | S_IWUSR, rtc_sysfs_show_wakealarm, rtc_sysfs_set_wakealarm); @@ -157,71 +199,36 @@ static const CLASS_DEVICE_ATTR(wakealarm, S_IRUGO | S_IWUSR, * suspend-to-disk. So: no attribute unless that side effect is possible. * (Userspace may disable that mechanism later.) */ -static inline int rtc_does_wakealarm(struct class_device *class_dev) +static inline int rtc_does_wakealarm(struct rtc_device *rtc) { - struct rtc_device *rtc; - - if (!device_can_wakeup(class_dev->dev)) + if (!device_can_wakeup(rtc->dev.parent)) return 0; - rtc = to_rtc_device(class_dev); return rtc->ops->set_alarm != NULL; } -static int rtc_sysfs_add_device(struct class_device *class_dev, - struct class_interface *class_intf) +void rtc_sysfs_add_device(struct rtc_device *rtc) { int err; - dev_dbg(class_dev->dev, "rtc intf: sysfs\n"); + /* not all RTCs support both alarms and wakeup */ + if (!rtc_does_wakealarm(rtc)) + return; - err = sysfs_create_group(&class_dev->kobj, &rtc_attr_group); + err = device_create_file(&rtc->dev, &dev_attr_wakealarm); if (err) - dev_err(class_dev->dev, "failed to create %s\n", - "sysfs attributes"); - else if (rtc_does_wakealarm(class_dev)) { - /* not all RTCs support both alarms and wakeup */ - err = class_device_create_file(class_dev, - &class_device_attr_wakealarm); - if (err) { - dev_err(class_dev->dev, "failed to create %s\n", - "alarm attribute"); - sysfs_remove_group(&class_dev->kobj, &rtc_attr_group); - } - } - - return err; + dev_err(rtc->dev.parent, + "failed to create alarm attribute, %d\n", err); } -static void rtc_sysfs_remove_device(struct class_device *class_dev, - struct class_interface *class_intf) +void rtc_sysfs_del_device(struct rtc_device *rtc) { - if (rtc_does_wakealarm(class_dev)) - class_device_remove_file(class_dev, - &class_device_attr_wakealarm); - sysfs_remove_group(&class_dev->kobj, &rtc_attr_group); + /* REVISIT did we add it successfully? */ + if (rtc_does_wakealarm(rtc)) + device_remove_file(&rtc->dev, &dev_attr_wakealarm); } -/* 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) +void __init rtc_sysfs_init(struct class *rtc_class) { - class_interface_unregister(&rtc_sysfs_interface); + rtc_class->dev_attrs = rtc_attrs; } - -subsys_initcall(rtc_sysfs_init); -module_exit(rtc_sysfs_exit); - -MODULE_AUTHOR("Alessandro Zummo "); -MODULE_DESCRIPTION("RTC class sysfs interface"); -MODULE_LICENSE("GPL");