diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/Kconfig | 44 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 5 | ||||
| -rw-r--r-- | drivers/rtc/class.c | 145 | ||||
| -rw-r--r-- | drivers/rtc/hctosys.c | 69 | ||||
| -rw-r--r-- | drivers/rtc/interface.c | 277 |
5 files changed, 537 insertions, 3 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 15df7c130fa6..a256f67b78e4 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -1,6 +1,46 @@ -# +\# # RTC class/drivers configuration # +menu "Real Time Clock" + config RTC_LIB - tristate
\ No newline at end of file + tristate + +config RTC_CLASS + tristate "RTC class" + depends on EXPERIMENTAL + default n + select RTC_LIB + help + Generic RTC class support. If you say yes here, you will + be allowed to plug one or more RTCs to your system. You will + probably want to enable one of more of the interfaces below. + + This driver can also be built as a module. If so, the module + will be called rtc-class. + +config RTC_HCTOSYS + bool "Set system time from RTC on startup" + depends on RTC_CLASS = y + default y + help + If you say yes here, the system time will be set using + the value read from the specified RTC device. This is useful + in order to avoid unnecessary fschk runs. + +config RTC_HCTOSYS_DEVICE + string "The RTC to read the time from" + depends on RTC_HCTOSYS = y + default "rtc0" + help + The RTC device that will be used as the source for + the system time, usually rtc0. + +comment "RTC interfaces" + depends on RTC_CLASS + +comment "RTC drivers" + depends on RTC_CLASS + +endmenu diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index eb9ad77c3e95..7b87f3710dff 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -2,4 +2,7 @@ # Makefile for RTC class/drivers. # -obj-$(CONFIG_RTC_LIB) += rtc-lib.o +obj-$(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 diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c new file mode 100644 index 000000000000..8533936d50d8 --- /dev/null +++ b/drivers/rtc/class.c @@ -0,0 +1,145 @@ +/* + * RTC subsystem, base class + * + * Copyright (C) 2005 Tower Technologies + * Author: Alessandro Zummo <a.zummo@towertech.it> + * + * class skeleton from drivers/hwmon/hwmon.c + * + * 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> +#include <linux/kdev_t.h> +#include <linux/idr.h> + +static DEFINE_IDR(rtc_idr); +static DEFINE_MUTEX(idr_lock); +struct class *rtc_class; + +static void rtc_device_release(struct class_device *class_dev) +{ + struct rtc_device *rtc = to_rtc_device(class_dev); + mutex_lock(&idr_lock); + idr_remove(&rtc_idr, rtc->id); + mutex_unlock(&idr_lock); + kfree(rtc); +} + +/** + * rtc_device_register - register w/ RTC class + * @dev: the device to register + * + * rtc_device_unregister() must be called when the class device is no + * longer needed. + * + * Returns the pointer to the new struct class device. + */ +struct rtc_device *rtc_device_register(const char *name, struct device *dev, + struct rtc_class_ops *ops, + struct module *owner) +{ + struct rtc_device *rtc; + int id, err; + + if (idr_pre_get(&rtc_idr, GFP_KERNEL) == 0) { + err = -ENOMEM; + goto exit; + } + + + mutex_lock(&idr_lock); + err = idr_get_new(&rtc_idr, NULL, &id); + mutex_unlock(&idr_lock); + + if (err < 0) + goto exit; + + id = id & MAX_ID_MASK; + + rtc = kzalloc(sizeof(struct rtc_device), GFP_KERNEL); + if (rtc == NULL) { + err = -ENOMEM; + goto exit_idr; + } + + rtc->id = id; + rtc->ops = ops; + rtc->owner = owner; + rtc->class_dev.dev = dev; + rtc->class_dev.class = rtc_class; + rtc->class_dev.release = rtc_device_release; + + mutex_init(&rtc->ops_lock); + spin_lock_init(&rtc->irq_lock); + spin_lock_init(&rtc->irq_task_lock); + + strlcpy(rtc->name, name, RTC_DEVICE_NAME_SIZE); + snprintf(rtc->class_dev.class_id, BUS_ID_SIZE, "rtc%d", id); + + err = class_device_register(&rtc->class_dev); + if (err) + goto exit_kfree; + + dev_info(dev, "rtc core: registered %s as %s\n", + rtc->name, rtc->class_dev.class_id); + + return rtc; + +exit_kfree: + kfree(rtc); + +exit_idr: + idr_remove(&rtc_idr, id); + +exit: + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(rtc_device_register); + + +/** + * rtc_device_unregister - removes the previously registered RTC class device + * + * @rtc: the RTC class device to destroy + */ +void rtc_device_unregister(struct rtc_device *rtc) +{ + mutex_lock(&rtc->ops_lock); + rtc->ops = NULL; + mutex_unlock(&rtc->ops_lock); + class_device_unregister(&rtc->class_dev); +} +EXPORT_SYMBOL_GPL(rtc_device_unregister); + +int rtc_interface_register(struct class_interface *intf) +{ + intf->class = rtc_class; + return class_interface_register(intf); +} +EXPORT_SYMBOL_GPL(rtc_interface_register); + +static int __init rtc_init(void) +{ + rtc_class = class_create(THIS_MODULE, "rtc"); + if (IS_ERR(rtc_class)) { + printk(KERN_ERR "%s: couldn't create class\n", __FILE__); + return PTR_ERR(rtc_class); + } + return 0; +} + +static void __exit rtc_exit(void) +{ + class_destroy(rtc_class); +} + +module_init(rtc_init); +module_exit(rtc_exit); + +MODULE_AUTHOR("Alessandro Zummo <a.zummo@towerteh.it>"); +MODULE_DESCRIPTION("RTC class support"); +MODULE_LICENSE("GPL"); diff --git a/drivers/rtc/hctosys.c b/drivers/rtc/hctosys.c new file mode 100644 index 000000000000..d02fe9a0001f --- /dev/null +++ b/drivers/rtc/hctosys.c @@ -0,0 +1,69 @@ +/* + * RTC subsystem, initialize system time on startup + * + * 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/rtc.h> + +/* IMPORTANT: the RTC only stores whole seconds. It is arbitrary + * whether it stores the most close value or the value with partial + * seconds truncated. However, it is important that we use it to store + * the truncated value. This is because otherwise it is necessary, + * in an rtc sync function, to read both xtime.tv_sec and + * xtime.tv_nsec. On some processors (i.e. ARM), an atomic read + * of >32bits is not possible. So storing the most close value would + * slow down the sync API. So here we have the truncated value and + * the best guess is to add 0.5s. + */ + +static int __init rtc_hctosys(void) +{ + int err; + struct rtc_time tm; + struct class_device *class_dev = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE); + + if (class_dev == NULL) { + printk("%s: unable to open rtc device (%s)\n", + __FILE__, CONFIG_RTC_HCTOSYS_DEVICE); + return -ENODEV; + } + + err = rtc_read_time(class_dev, &tm); + if (err == 0) { + err = rtc_valid_tm(&tm); + if (err == 0) { + struct timespec tv; + + tv.tv_nsec = NSEC_PER_SEC >> 1; + + rtc_tm_to_time(&tm, &tv.tv_sec); + + do_settimeofday(&tv); + + dev_info(class_dev->dev, + "setting the system clock to " + "%d-%02d-%02d %02d:%02d:%02d (%u)\n", + tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, + tm.tm_hour, tm.tm_min, tm.tm_sec, + (unsigned int) tv.tv_sec); + } + else + dev_err(class_dev->dev, + "hctosys: invalid date/time\n"); + } + else + dev_err(class_dev->dev, + "hctosys: unable to read the hardware clock\n"); + + rtc_class_close(class_dev); + + return 0; +} + +late_initcall(rtc_hctosys); diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c new file mode 100644 index 000000000000..56e490709b87 --- /dev/null +++ b/drivers/rtc/interface.c @@ -0,0 +1,277 @@ +/* + * RTC subsystem, interface functions + * + * Copyright (C) 2005 Tower Technologies + * Author: Alessandro Zummo <a.zummo@towertech.it> + * + * 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 version 2 as + * published by the Free Software Foundation. +*/ + +#include <linux/rtc.h> + +int rtc_read_time(struct class_device *class_dev, struct rtc_time *tm) +{ + int err; + struct rtc_device *rtc = to_rtc_device(class_dev); + + err = mutex_lock_interruptible(&rtc->ops_lock); + if (err) + return -EBUSY; + + if (!rtc->ops) + err = -ENODEV; + else if (!rtc->ops->read_time) + err = -EINVAL; + else { + memset(tm, 0, sizeof(struct rtc_time)); + err = rtc->ops->read_time(class_dev->dev, tm); + } + + mutex_unlock(&rtc->ops_lock); + return err; +} +EXPORT_SYMBOL_GPL(rtc_read_time); + +int rtc_set_time(struct class_device *class_dev, struct rtc_time *tm) +{ + int err; + struct rtc_device *rtc = to_rtc_device(class_dev); + + err = rtc_valid_tm(tm); + if (err != 0) + return err; + + err = mutex_lock_interruptible(&rtc->ops_lock); + if (err) + return -EBUSY; + + if (!rtc->ops) + err = -ENODEV; + else if (!rtc->ops->set_time) + err = -EINVAL; + else + err = rtc->ops->set_time(class_dev->dev, tm); + + mutex_unlock(&rtc->ops_lock); + return err; +} +EXPORT_SYMBOL_GPL(rtc_set_time); + +int rtc_set_mmss(struct class_device *class_dev, unsigned long secs) +{ + int err; + struct rtc_device *rtc = to_rtc_device(class_dev); + + err = mutex_lock_interruptible(&rtc->ops_lock); + if (err) + return -EBUSY; + + if (!rtc->ops) + err = -ENODEV; + else if (rtc->ops->set_mmss) + err = rtc->ops->set_mmss(class_dev->dev, secs); + else if (rtc->ops->read_time && rtc->ops->set_time) { + struct rtc_time new, old; + + err = rtc->ops->read_time(class_dev->dev, &old); + if (err == 0) { + rtc_time_to_tm(secs, &new); + + /* + * avoid writing when we're going to change the day of + * the month. We will retry in the next minute. This + * basically means that if the RTC must not drift + * by more than 1 minute in 11 minutes. + */ + if (!((old.tm_hour == 23 && old.tm_min == 59) || + (new.tm_hour == 23 && new.tm_min == 59))) + err = rtc->ops->set_time(class_dev->dev, &new); + } + } + else + err = -EINVAL; + + mutex_unlock(&rtc->ops_lock); + + return err; +} +EXPORT_SYMBOL_GPL(rtc_set_mmss); + +int rtc_read_alarm(struct class_device *class_dev, struct rtc_wkalrm *alarm) +{ + int err; + struct rtc_device *rtc = to_rtc_device(class_dev); + + err = mutex_lock_interruptible(&rtc->ops_lock); + if (err) + return -EBUSY; + + if (rtc->ops == NULL) + err = -ENODEV; + else if (!rtc->ops->read_alarm) + err = -EINVAL; + else { + memset(alarm, 0, sizeof(struct rtc_wkalrm)); + err = rtc->ops->read_alarm(class_dev->dev, alarm); + } + + mutex_unlock(&rtc->ops_lock); + return err; +} +EXPORT_SYMBOL_GPL(rtc_read_alarm); + +int rtc_set_alarm(struct class_device *class_dev, struct rtc_wkalrm *alarm) +{ + int err; + struct rtc_device *rtc = to_rtc_device(class_dev); + + err = mutex_lock_interruptible(&rtc->ops_lock); + if (err) + return -EBUSY; + + if (!rtc->ops) + err = -ENODEV; + else if (!rtc->ops->set_alarm) + err = -EINVAL; + else + err = rtc->ops->set_alarm(class_dev->dev, alarm); + + mutex_unlock(&rtc->ops_lock); + return err; +} +EXPORT_SYMBOL_GPL(rtc_set_alarm); + +void rtc_update_irq(struct class_device *class_dev, + unsigned long num, unsigned long events) +{ + struct rtc_device *rtc = to_rtc_device(class_dev); + + spin_lock(&rtc->irq_lock); + rtc->irq_data = (rtc->irq_data + (num << 8)) | events; + spin_unlock(&rtc->irq_lock); + + spin_lock(&rtc->irq_task_lock); + if (rtc->irq_task) + rtc->irq_task->func(rtc->irq_task->private_data); + spin_unlock(&rtc->irq_task_lock); + + wake_up_interruptible(&rtc->irq_queue); + kill_fasync(&rtc->async_queue, SIGIO, POLL_IN); +} +EXPORT_SYMBOL_GPL(rtc_update_irq); + +struct class_device *rtc_class_open(char *name) +{ + struct class_device *class_dev = NULL, + *class_dev_tmp; + + down(&rtc_class->sem); + list_for_each_entry(class_dev_tmp, &rtc_class->children, node) { + if (strncmp(class_dev_tmp->class_id, name, BUS_ID_SIZE) == 0) { + class_dev = class_dev_tmp; + break; + } + } + + if (class_dev) { + if (!try_module_get(to_rtc_device(class_dev)->owner)) + class_dev = NULL; + } + up(&rtc_class->sem); + + return class_dev; +} +EXPORT_SYMBOL_GPL(rtc_class_open); + +void rtc_class_close(struct class_device *class_dev) +{ + module_put(to_rtc_device(class_dev)->owner); +} +EXPORT_SYMBOL_GPL(rtc_class_close); + +int rtc_irq_register(struct class_device *class_dev, struct rtc_task *task) +{ + int retval = -EBUSY; + struct rtc_device *rtc = to_rtc_device(class_dev); + + if (task == NULL || task->func == NULL) + return -EINVAL; + + spin_lock(&rtc->irq_task_lock); + if (rtc->irq_task == NULL) { + rtc->irq_task = task; + retval = 0; + } + spin_unlock(&rtc->irq_task_lock); + + return retval; +} +EXPORT_SYMBOL_GPL(rtc_irq_register); + +void rtc_irq_unregister(struct class_device *class_dev, struct rtc_task *task) +{ + struct rtc_device *rtc = to_rtc_device(class_dev); + + spin_lock(&rtc->irq_task_lock); + if (rtc->irq_task == task) + rtc->irq_task = NULL; + spin_unlock(&rtc->irq_task_lock); +} +EXPORT_SYMBOL_GPL(rtc_irq_unregister); + +int rtc_irq_set_state(struct class_device *class_dev, struct rtc_task *task, int enabled) +{ + int err = 0; + unsigned long flags; + struct rtc_device *rtc = to_rtc_device(class_dev); + + spin_lock_irqsave(&rtc->irq_task_lock, flags); + if (rtc->irq_task != task) + err = -ENXIO; + spin_unlock_irqrestore(&rtc->irq_task_lock, flags); + + if (err == 0) + err = rtc->ops->irq_set_state(class_dev->dev, enabled); + + return err; +} +EXPORT_SYMBOL_GPL(rtc_irq_set_state); + +int rtc_irq_set_freq(struct class_device *class_dev, struct rtc_task *task, int freq) +{ + int err = 0, tmp = 0; + unsigned long flags; + struct rtc_device *rtc = to_rtc_device(class_dev); + + /* allowed range is 2-8192 */ + if (freq < 2 || freq > 8192) + return -EINVAL; +/* + FIXME: this does not belong here, will move where appropriate + at a later stage. It cannot hurt right now, trust me :) + if ((freq > rtc_max_user_freq) && (!capable(CAP_SYS_RESOURCE))) + return -EACCES; +*/ + /* check if freq is a power of 2 */ + while (freq > (1 << tmp)) + tmp++; + + if (freq != (1 << tmp)) + return -EINVAL; + + spin_lock_irqsave(&rtc->irq_task_lock, flags); + if (rtc->irq_task != task) + err = -ENXIO; + spin_unlock_irqrestore(&rtc->irq_task_lock, flags); + + if (err == 0) { + err = rtc->ops->irq_set_freq(class_dev->dev, freq); + if (err == 0) + rtc->irq_freq = freq; + } + return err; +} |