diff options
Diffstat (limited to 'drivers/rtc/class.c')
| -rw-r--r-- | drivers/rtc/class.c | 145 |
1 files changed, 145 insertions, 0 deletions
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"); |