ARM: tegra30: pm: flush L1 data before exit coherency on secondary CPU
[linux-2.6.git] / drivers / rtc / rtc-dev.c
index 2011567..cace6d3 100644 (file)
@@ -13,8 +13,9 @@
 
 #include <linux/module.h>
 #include <linux/rtc.h>
+#include <linux/sched.h>
+#include "rtc-core.h"
 
-static struct class *rtc_dev_class;
 static dev_t rtc_devt;
 
 #define RTC_DEV_MAX 16 /* 16 RTCs should be enough for everyone... */
@@ -24,17 +25,14 @@ static int rtc_dev_open(struct inode *inode, struct file *file)
        int err;
        struct rtc_device *rtc = container_of(inode->i_cdev,
                                        struct rtc_device, char_dev);
-       struct rtc_class_ops *ops = rtc->ops;
+       const struct rtc_class_ops *ops = rtc->ops;
 
-       /* We keep the lock as long as the device is in use
-        * and return immediately if busy
-        */
-       if (!(mutex_trylock(&rtc->char_lock)))
+       if (test_and_set_bit_lock(RTC_DEV_BUSY, &rtc->flags))
                return -EBUSY;
 
-       file->private_data = &rtc->class_dev;
+       file->private_data = rtc;
 
-       err = ops->open ? ops->open(rtc->class_dev.dev) : 0;
+       err = ops->open ? ops->open(rtc->dev.parent) : 0;
        if (err == 0) {
                spin_lock_irq(&rtc->irq_lock);
                rtc->irq_data = 0;
@@ -43,16 +41,115 @@ static int rtc_dev_open(struct inode *inode, struct file *file)
                return 0;
        }
 
-       /* something has gone wrong, release the lock */
-       mutex_unlock(&rtc->char_lock);
+       /* something has gone wrong */
+       clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
        return err;
 }
 
+#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
+/*
+ * Routine to poll RTC seconds field for change as often as possible,
+ * after first RTC_UIE use timer to reduce polling
+ */
+static void rtc_uie_task(struct work_struct *work)
+{
+       struct rtc_device *rtc =
+               container_of(work, struct rtc_device, uie_task);
+       struct rtc_time tm;
+       int num = 0;
+       int err;
+
+       err = rtc_read_time(rtc, &tm);
+
+       spin_lock_irq(&rtc->irq_lock);
+       if (rtc->stop_uie_polling || err) {
+               rtc->uie_task_active = 0;
+       } else if (rtc->oldsecs != tm.tm_sec) {
+               num = (tm.tm_sec + 60 - rtc->oldsecs) % 60;
+               rtc->oldsecs = tm.tm_sec;
+               rtc->uie_timer.expires = jiffies + HZ - (HZ/10);
+               rtc->uie_timer_active = 1;
+               rtc->uie_task_active = 0;
+               add_timer(&rtc->uie_timer);
+       } else if (schedule_work(&rtc->uie_task) == 0) {
+               rtc->uie_task_active = 0;
+       }
+       spin_unlock_irq(&rtc->irq_lock);
+       if (num)
+               rtc_handle_legacy_irq(rtc, num, RTC_UF);
+}
+static void rtc_uie_timer(unsigned long data)
+{
+       struct rtc_device *rtc = (struct rtc_device *)data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&rtc->irq_lock, flags);
+       rtc->uie_timer_active = 0;
+       rtc->uie_task_active = 1;
+       if ((schedule_work(&rtc->uie_task) == 0))
+               rtc->uie_task_active = 0;
+       spin_unlock_irqrestore(&rtc->irq_lock, flags);
+}
+
+static int clear_uie(struct rtc_device *rtc)
+{
+       spin_lock_irq(&rtc->irq_lock);
+       if (rtc->uie_irq_active) {
+               rtc->stop_uie_polling = 1;
+               if (rtc->uie_timer_active) {
+                       spin_unlock_irq(&rtc->irq_lock);
+                       del_timer_sync(&rtc->uie_timer);
+                       spin_lock_irq(&rtc->irq_lock);
+                       rtc->uie_timer_active = 0;
+               }
+               if (rtc->uie_task_active) {
+                       spin_unlock_irq(&rtc->irq_lock);
+                       flush_scheduled_work();
+                       spin_lock_irq(&rtc->irq_lock);
+               }
+               rtc->uie_irq_active = 0;
+       }
+       spin_unlock_irq(&rtc->irq_lock);
+       return 0;
+}
+
+static int set_uie(struct rtc_device *rtc)
+{
+       struct rtc_time tm;
+       int err;
+
+       err = rtc_read_time(rtc, &tm);
+       if (err)
+               return err;
+       spin_lock_irq(&rtc->irq_lock);
+       if (!rtc->uie_irq_active) {
+               rtc->uie_irq_active = 1;
+               rtc->stop_uie_polling = 0;
+               rtc->oldsecs = tm.tm_sec;
+               rtc->uie_task_active = 1;
+               if (schedule_work(&rtc->uie_task) == 0)
+                       rtc->uie_task_active = 0;
+       }
+       rtc->irq_data = 0;
+       spin_unlock_irq(&rtc->irq_lock);
+       return 0;
+}
+
+int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc, unsigned int enabled)
+{
+       if (enabled)
+               return set_uie(rtc);
+       else
+               return clear_uie(rtc);
+}
+EXPORT_SYMBOL(rtc_dev_update_irq_enable_emul);
+
+#endif /* CONFIG_RTC_INTF_DEV_UIE_EMUL */
 
 static ssize_t
 rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 {
-       struct rtc_device *rtc = to_rtc_device(file->private_data);
+       struct rtc_device *rtc = file->private_data;
 
        DECLARE_WAITQUEUE(wait, current);
        unsigned long data;
@@ -90,7 +187,7 @@ rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
        if (ret == 0) {
                /* Check for any data updates */
                if (rtc->ops->read_callback)
-                       data = rtc->ops->read_callback(rtc->class_dev.dev,
+                       data = rtc->ops->read_callback(rtc->dev.parent,
                                                       data);
 
                if (sizeof(int) != sizeof(long) &&
@@ -106,7 +203,7 @@ rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 
 static unsigned int rtc_dev_poll(struct file *file, poll_table *wait)
 {
-       struct rtc_device *rtc = to_rtc_device(file->private_data);
+       struct rtc_device *rtc = file->private_data;
        unsigned long data;
 
        poll_wait(file, &rtc->irq_queue, wait);
@@ -116,83 +213,172 @@ static unsigned int rtc_dev_poll(struct file *file, poll_table *wait)
        return (data != 0) ? (POLLIN | POLLRDNORM) : 0;
 }
 
-static int rtc_dev_ioctl(struct inode *inode, struct file *file,
+static long rtc_dev_ioctl(struct file *file,
                unsigned int cmd, unsigned long arg)
 {
        int err = 0;
-       struct class_device *class_dev = file->private_data;
-       struct rtc_device *rtc = to_rtc_device(class_dev);
-       struct rtc_class_ops *ops = rtc->ops;
+       struct rtc_device *rtc = file->private_data;
+       const struct rtc_class_ops *ops = rtc->ops;
        struct rtc_time tm;
        struct rtc_wkalrm alarm;
        void __user *uarg = (void __user *) arg;
 
-       /* avoid conflicting IRQ users */
-       if (cmd == RTC_PIE_ON || cmd == RTC_PIE_OFF || cmd == RTC_IRQP_SET) {
-               spin_lock(&rtc->irq_task_lock);
-               if (rtc->irq_task)
-                       err = -EBUSY;
-               spin_unlock(&rtc->irq_task_lock);
+       err = mutex_lock_interruptible(&rtc->ops_lock);
+       if (err)
+               return err;
 
-               if (err < 0)
-                       return err;
-       }
+       /* check that the calling task has appropriate permissions
+        * for certain ioctls. doing this check here is useful
+        * to avoid duplicate code in each driver.
+        */
+       switch (cmd) {
+       case RTC_EPOCH_SET:
+       case RTC_SET_TIME:
+               if (!capable(CAP_SYS_TIME))
+                       err = -EACCES;
+               break;
 
-       /* try the driver's ioctl interface */
-       if (ops->ioctl) {
-               err = ops->ioctl(class_dev->dev, cmd, arg);
-               if (err != -ENOIOCTLCMD)
-                       return err;
+       case RTC_IRQP_SET:
+               if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE))
+                       err = -EACCES;
+               break;
+
+       case RTC_PIE_ON:
+               if (rtc->irq_freq > rtc->max_user_freq &&
+                               !capable(CAP_SYS_RESOURCE))
+                       err = -EACCES;
+               break;
        }
 
-       /* if the driver does not provide the ioctl interface
-        * or if that particular ioctl was not implemented
-        * (-ENOIOCTLCMD), we will try to emulate here.
+       if (err)
+               goto done;
+
+       /*
+        * Drivers *SHOULD NOT* provide ioctl implementations
+        * for these requests.  Instead, provide methods to
+        * support the following code, so that the RTC's main
+        * features are accessible without using ioctls.
+        *
+        * RTC and alarm times will be in UTC, by preference,
+        * but dual-booting with MS-Windows implies RTCs must
+        * use the local wall clock time.
         */
 
        switch (cmd) {
        case RTC_ALM_READ:
-               err = rtc_read_alarm(class_dev, &alarm);
+               mutex_unlock(&rtc->ops_lock);
+
+               err = rtc_read_alarm(rtc, &alarm);
                if (err < 0)
                        return err;
 
                if (copy_to_user(uarg, &alarm.time, sizeof(tm)))
-                       return -EFAULT;
-               break;
+                       err = -EFAULT;
+               return err;
 
        case RTC_ALM_SET:
+               mutex_unlock(&rtc->ops_lock);
+
                if (copy_from_user(&alarm.time, uarg, sizeof(tm)))
                        return -EFAULT;
 
                alarm.enabled = 0;
                alarm.pending = 0;
-               alarm.time.tm_mday = -1;
-               alarm.time.tm_mon = -1;
-               alarm.time.tm_year = -1;
                alarm.time.tm_wday = -1;
                alarm.time.tm_yday = -1;
                alarm.time.tm_isdst = -1;
-               err = rtc_set_alarm(class_dev, &alarm);
-               break;
+
+               /* RTC_ALM_SET alarms may be up to 24 hours in the future.
+                * Rather than expecting every RTC to implement "don't care"
+                * for day/month/year fields, just force the alarm to have
+                * the right values for those fields.
+                *
+                * RTC_WKALM_SET should be used instead.  Not only does it
+                * eliminate the need for a separate RTC_AIE_ON call, it
+                * doesn't have the "alarm 23:59:59 in the future" race.
+                *
+                * NOTE:  some legacy code may have used invalid fields as
+                * wildcards, exposing hardware "periodic alarm" capabilities.
+                * Not supported here.
+                */
+               {
+                       unsigned long now, then;
+
+                       err = rtc_read_time(rtc, &tm);
+                       if (err < 0)
+                               return err;
+                       rtc_tm_to_time(&tm, &now);
+
+                       alarm.time.tm_mday = tm.tm_mday;
+                       alarm.time.tm_mon = tm.tm_mon;
+                       alarm.time.tm_year = tm.tm_year;
+                       err  = rtc_valid_tm(&alarm.time);
+                       if (err < 0)
+                               return err;
+                       rtc_tm_to_time(&alarm.time, &then);
+
+                       /* alarm may need to wrap into tomorrow */
+                       if (then < now) {
+                               rtc_time_to_tm(now + 24 * 60 * 60, &tm);
+                               alarm.time.tm_mday = tm.tm_mday;
+                               alarm.time.tm_mon = tm.tm_mon;
+                               alarm.time.tm_year = tm.tm_year;
+                       }
+               }
+
+               return rtc_set_alarm(rtc, &alarm);
 
        case RTC_RD_TIME:
-               err = rtc_read_time(class_dev, &tm);
+               mutex_unlock(&rtc->ops_lock);
+
+               err = rtc_read_time(rtc, &tm);
                if (err < 0)
                        return err;
 
                if (copy_to_user(uarg, &tm, sizeof(tm)))
-                       return -EFAULT;
-               break;
+                       err = -EFAULT;
+               return err;
 
        case RTC_SET_TIME:
-               if (!capable(CAP_SYS_TIME))
-                       return -EACCES;
+               mutex_unlock(&rtc->ops_lock);
 
                if (copy_from_user(&tm, uarg, sizeof(tm)))
                        return -EFAULT;
 
-               err = rtc_set_time(class_dev, &tm);
+               return rtc_set_time(rtc, &tm);
+
+       case RTC_PIE_ON:
+               err = rtc_irq_set_state(rtc, NULL, 1);
                break;
+
+       case RTC_PIE_OFF:
+               err = rtc_irq_set_state(rtc, NULL, 0);
+               break;
+
+       case RTC_AIE_ON:
+               mutex_unlock(&rtc->ops_lock);
+               return rtc_alarm_irq_enable(rtc, 1);
+
+       case RTC_AIE_OFF:
+               mutex_unlock(&rtc->ops_lock);
+               return rtc_alarm_irq_enable(rtc, 0);
+
+       case RTC_UIE_ON:
+               mutex_unlock(&rtc->ops_lock);
+               return rtc_update_irq_enable(rtc, 1);
+
+       case RTC_UIE_OFF:
+               mutex_unlock(&rtc->ops_lock);
+               return rtc_update_irq_enable(rtc, 0);
+
+       case RTC_IRQP_SET:
+               err = rtc_irq_set_freq(rtc, NULL, arg);
+               break;
+
+       case RTC_IRQP_READ:
+               err = put_user(rtc->irq_freq, (unsigned long __user *)uarg);
+               break;
+
 #if 0
        case RTC_EPOCH_SET:
 #ifndef rtc_epoch
@@ -203,10 +389,6 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
                        err = -EINVAL;
                        break;
                }
-               if (!capable(CAP_SYS_TIME)) {
-                       err = -EACCES;
-                       break;
-               }
                rtc_epoch = arg;
                err = 0;
 #endif
@@ -217,52 +399,75 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
                break;
 #endif
        case RTC_WKALM_SET:
+               mutex_unlock(&rtc->ops_lock);
                if (copy_from_user(&alarm, uarg, sizeof(alarm)))
                        return -EFAULT;
 
-               err = rtc_set_alarm(class_dev, &alarm);
-               break;
+               return rtc_set_alarm(rtc, &alarm);
 
        case RTC_WKALM_RD:
-               err = rtc_read_alarm(class_dev, &alarm);
+               mutex_unlock(&rtc->ops_lock);
+               err = rtc_read_alarm(rtc, &alarm);
                if (err < 0)
                        return err;
 
                if (copy_to_user(uarg, &alarm, sizeof(alarm)))
-                       return -EFAULT;
-               break;
+                       err = -EFAULT;
+               return err;
 
        default:
-               err = -ENOTTY;
+               /* Finally try the driver's ioctl interface */
+               if (ops->ioctl) {
+                       err = ops->ioctl(rtc->dev.parent, cmd, arg);
+                       if (err == -ENOIOCTLCMD)
+                               err = -ENOTTY;
+               } else
+                       err = -ENOTTY;
                break;
        }
 
+done:
+       mutex_unlock(&rtc->ops_lock);
        return err;
 }
 
+static int rtc_dev_fasync(int fd, struct file *file, int on)
+{
+       struct rtc_device *rtc = file->private_data;
+       return fasync_helper(fd, file, on, &rtc->async_queue);
+}
+
 static int rtc_dev_release(struct inode *inode, struct file *file)
 {
-       struct rtc_device *rtc = to_rtc_device(file->private_data);
+       struct rtc_device *rtc = file->private_data;
+
+       /* We shut down the repeating IRQs that userspace enabled,
+        * since nothing is listening to them.
+        *  - Update (UIE) ... currently only managed through ioctls
+        *  - Periodic (PIE) ... also used through rtc_*() interface calls
+        *
+        * Leave the alarm alone; it may be set to trigger a system wakeup
+        * later, or be used by kernel code, and is a one-shot event anyway.
+        */
+
+       /* Keep ioctl until all drivers are converted */
+       rtc_dev_ioctl(file, RTC_UIE_OFF, 0);
+       rtc_update_irq_enable(rtc, 0);
+       rtc_irq_set_state(rtc, NULL, 0);
 
        if (rtc->ops->release)
-               rtc->ops->release(rtc->class_dev.dev);
+               rtc->ops->release(rtc->dev.parent);
 
-       mutex_unlock(&rtc->char_lock);
+       clear_bit_unlock(RTC_DEV_BUSY, &rtc->flags);
        return 0;
 }
 
-static int rtc_dev_fasync(int fd, struct file *file, int on)
-{
-       struct rtc_device *rtc = to_rtc_device(file->private_data);
-       return fasync_helper(fd, file, on, &rtc->async_queue);
-}
-
-static struct file_operations rtc_dev_fops = {
+static const struct file_operations rtc_dev_fops = {
        .owner          = THIS_MODULE,
        .llseek         = no_llseek,
        .read           = rtc_dev_read,
        .poll           = rtc_dev_poll,
-       .ioctl          = rtc_dev_ioctl,
+       .unlocked_ioctl = rtc_dev_ioctl,
        .open           = rtc_dev_open,
        .release        = rtc_dev_release,
        .fasync         = rtc_dev_fasync,
@@ -270,118 +475,55 @@ static struct file_operations rtc_dev_fops = {
 
 /* insertion/removal hooks */
 
-static int rtc_dev_add_device(struct class_device *class_dev,
-                               struct class_interface *class_intf)
+void rtc_dev_prepare(struct rtc_device *rtc)
 {
-       int err = 0;
-       struct rtc_device *rtc = to_rtc_device(class_dev);
+       if (!rtc_devt)
+               return;
 
        if (rtc->id >= RTC_DEV_MAX) {
-               dev_err(class_dev->dev, "too many RTCs\n");
-               return -EINVAL;
+               pr_debug("%s: too many RTC devices\n", rtc->name);
+               return;
        }
 
-       mutex_init(&rtc->char_lock);
-       spin_lock_init(&rtc->irq_lock);
-       init_waitqueue_head(&rtc->irq_queue);
+       rtc->dev.devt = MKDEV(MAJOR(rtc_devt), rtc->id);
+
+#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
+       INIT_WORK(&rtc->uie_task, rtc_uie_task);
+       setup_timer(&rtc->uie_timer, rtc_uie_timer, (unsigned long)rtc);
+#endif
 
        cdev_init(&rtc->char_dev, &rtc_dev_fops);
        rtc->char_dev.owner = rtc->owner;
+}
 
-       if (cdev_add(&rtc->char_dev, MKDEV(MAJOR(rtc_devt), rtc->id), 1)) {
-               cdev_del(&rtc->char_dev);
-               dev_err(class_dev->dev,
-                       "failed to add char device %d:%d\n",
+void rtc_dev_add_device(struct rtc_device *rtc)
+{
+       if (cdev_add(&rtc->char_dev, rtc->dev.devt, 1))
+               printk(KERN_WARNING "%s: failed to add char device %d:%d\n",
+                       rtc->name, MAJOR(rtc_devt), rtc->id);
+       else
+               pr_debug("%s: dev (%d:%d)\n", rtc->name,
                        MAJOR(rtc_devt), rtc->id);
-               return -ENODEV;
-       }
-
-       rtc->rtc_dev = class_device_create(rtc_dev_class, NULL,
-                                               MKDEV(MAJOR(rtc_devt), rtc->id),
-                                               class_dev->dev, "rtc%d", rtc->id);
-       if (IS_ERR(rtc->rtc_dev)) {
-               dev_err(class_dev->dev, "cannot create rtc_dev device\n");
-               err = PTR_ERR(rtc->rtc_dev);
-               goto err_cdev_del;
-       }
-
-       dev_info(class_dev->dev, "rtc intf: dev (%d:%d)\n",
-               MAJOR(rtc->rtc_dev->devt),
-               MINOR(rtc->rtc_dev->devt));
-
-       return 0;
-
-err_cdev_del:
-
-       cdev_del(&rtc->char_dev);
-       return err;
 }
 
-static void rtc_dev_remove_device(struct class_device *class_dev,
-                                       struct class_interface *class_intf)
+void rtc_dev_del_device(struct rtc_device *rtc)
 {
-       struct rtc_device *rtc = to_rtc_device(class_dev);
-
-       if (rtc->rtc_dev) {
-               dev_dbg(class_dev->dev, "removing char %d:%d\n",
-                       MAJOR(rtc->rtc_dev->devt),
-                       MINOR(rtc->rtc_dev->devt));
-
-               class_device_unregister(rtc->rtc_dev);
+       if (rtc->dev.devt)
                cdev_del(&rtc->char_dev);
-       }
 }
 
-/* interface registration */
-
-static struct class_interface rtc_dev_interface = {
-       .add = &rtc_dev_add_device,
-       .remove = &rtc_dev_remove_device,
-};
-
-static int __init rtc_dev_init(void)
+void __init rtc_dev_init(void)
 {
        int err;
 
-       rtc_dev_class = class_create(THIS_MODULE, "rtc-dev");
-       if (IS_ERR(rtc_dev_class))
-               return PTR_ERR(rtc_dev_class);
-
        err = alloc_chrdev_region(&rtc_devt, 0, RTC_DEV_MAX, "rtc");
-       if (err < 0) {
+       if (err < 0)
                printk(KERN_ERR "%s: failed to allocate char dev region\n",
                        __FILE__);
-               goto err_destroy_class;
-       }
-
-       err = rtc_interface_register(&rtc_dev_interface);
-       if (err < 0) {
-               printk(KERN_ERR "%s: failed to register the interface\n",
-                       __FILE__);
-               goto err_unregister_chrdev;
-       }
-
-       return 0;
-
-err_unregister_chrdev:
-       unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
-
-err_destroy_class:
-       class_destroy(rtc_dev_class);
-
-       return err;
 }
 
-static void __exit rtc_dev_exit(void)
+void __exit rtc_dev_exit(void)
 {
-       class_interface_unregister(&rtc_dev_interface);
-       class_destroy(rtc_dev_class);
-       unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
+       if (rtc_devt)
+               unregister_chrdev_region(rtc_devt, RTC_DEV_MAX);
 }
-
-module_init(rtc_dev_init);
-module_exit(rtc_dev_exit);
-
-MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
-MODULE_DESCRIPTION("RTC class dev interface");
-MODULE_LICENSE("GPL");