1 files changed, 128 insertions, 106 deletions

diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c
index f4e5f0040ff..d0493936925 100644
--- a/drivers/rtc/rtc-dev.c
+++ b/drivers/rtc/rtc-dev.c
@@ -11,8 +11,11 @@
  * published by the Free Software Foundation.
 */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/rtc.h>
+#include <linux/sched.h>
 #include "rtc-core.h"
 
 static dev_t rtc_devt;
@@ -26,10 +29,7 @@ static int rtc_dev_open(struct inode *inode, struct file *file)
 					struct rtc_device, char_dev);
 	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;
@@ -43,8 +43,8 @@ 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;
 }
 
@@ -63,8 +63,7 @@ static void rtc_uie_task(struct work_struct *work)
 
 	err = rtc_read_time(rtc, &tm);
 
-	local_irq_disable();
-	spin_lock(&rtc->irq_lock);
+	spin_lock_irq(&rtc->irq_lock);
 	if (rtc->stop_uie_polling || err) {
 		rtc->uie_task_active = 0;
 	} else if (rtc->oldsecs != tm.tm_sec) {
@@ -77,10 +76,9 @@ static void rtc_uie_task(struct work_struct *work)
 	} else if (schedule_work(&rtc->uie_task) == 0) {
 		rtc->uie_task_active = 0;
 	}
-	spin_unlock(&rtc->irq_lock);
+	spin_unlock_irq(&rtc->irq_lock);
 	if (num)
-		rtc_update_irq(rtc, num, RTC_UF | RTC_IRQF);
-	local_irq_enable();
+		rtc_handle_legacy_irq(rtc, num, RTC_UF);
 }
 static void rtc_uie_timer(unsigned long data)
 {
@@ -95,10 +93,10 @@ static void rtc_uie_timer(unsigned long data)
 	spin_unlock_irqrestore(&rtc->irq_lock, flags);
 }
 
-static void clear_uie(struct rtc_device *rtc)
+static int clear_uie(struct rtc_device *rtc)
 {
 	spin_lock_irq(&rtc->irq_lock);
-	if (rtc->irq_active) {
+	if (rtc->uie_irq_active) {
 		rtc->stop_uie_polling = 1;
 		if (rtc->uie_timer_active) {
 			spin_unlock_irq(&rtc->irq_lock);
@@ -111,9 +109,10 @@ static void clear_uie(struct rtc_device *rtc)
 			flush_scheduled_work();
 			spin_lock_irq(&rtc->irq_lock);
 		}
-		rtc->irq_active = 0;
+		rtc->uie_irq_active = 0;
 	}
 	spin_unlock_irq(&rtc->irq_lock);
+	return 0;
 }
 
 static int set_uie(struct rtc_device *rtc)
@@ -125,8 +124,8 @@ static int set_uie(struct rtc_device *rtc)
 	if (err)
 		return err;
 	spin_lock_irq(&rtc->irq_lock);
-	if (!rtc->irq_active) {
-		rtc->irq_active = 1;
+	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;
@@ -137,12 +136,22 @@ static int set_uie(struct rtc_device *rtc)
 	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;
@@ -196,7 +205,7 @@ 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);
@@ -206,7 +215,7 @@ 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;
@@ -216,6 +225,10 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
 	struct rtc_wkalrm alarm;
 	void __user *uarg = (void __user *) arg;
 
+	err = mutex_lock_interruptible(&rtc->ops_lock);
+	if (err)
+		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.
@@ -224,54 +237,50 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
 	case RTC_EPOCH_SET:
 	case RTC_SET_TIME:
 		if (!capable(CAP_SYS_TIME))
-			return -EACCES;
+			err = -EACCES;
 		break;
 
 	case RTC_IRQP_SET:
 		if (arg > rtc->max_user_freq && !capable(CAP_SYS_RESOURCE))
-			return -EACCES;
+			err = -EACCES;
 		break;
 
 	case RTC_PIE_ON:
-		if (!capable(CAP_SYS_RESOURCE))
-			return -EACCES;
+		if (rtc->irq_freq > rtc->max_user_freq &&
+				!capable(CAP_SYS_RESOURCE))
+			err = -EACCES;
 		break;
 	}
 
-	/* avoid conflicting IRQ users */
-	if (cmd == RTC_PIE_ON || cmd == RTC_PIE_OFF || cmd == RTC_IRQP_SET) {
-		spin_lock_irq(&rtc->irq_task_lock);
-		if (rtc->irq_task)
-			err = -EBUSY;
-		spin_unlock_irq(&rtc->irq_task_lock);
-
-		if (err < 0)
-			return err;
-	}
-
-	/* try the driver's ioctl interface */
-	if (ops->ioctl) {
-		err = ops->ioctl(rtc->dev.parent, cmd, arg);
-		if (err != -ENOIOCTLCMD)
-			return err;
-	}
-
-	/* 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:
+		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;
 
@@ -319,112 +328,129 @@ static int rtc_dev_ioctl(struct inode *inode, struct file *file,
 			}
 		}
 
-		err = rtc_set_alarm(rtc, &alarm);
-		break;
+		return rtc_set_alarm(rtc, &alarm);
 
 	case RTC_RD_TIME:
+		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:
+		mutex_unlock(&rtc->ops_lock);
+
 		if (copy_from_user(&tm, uarg, sizeof(tm)))
 			return -EFAULT;
 
-		err = rtc_set_time(rtc, &tm);
+		return rtc_set_time(rtc, &tm);
+
+	case RTC_PIE_ON:
+		err = rtc_irq_set_state(rtc, NULL, 1);
 		break;
 
-	case RTC_IRQP_READ:
-		if (ops->irq_set_freq)
-			err = put_user(rtc->irq_freq, (unsigned long __user *)uarg);
+	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:
-		if (ops->irq_set_freq)
-			err = rtc_irq_set_freq(rtc, rtc->irq_task, arg);
+		err = rtc_irq_set_freq(rtc, NULL, arg);
 		break;
 
-#if 0
-	case RTC_EPOCH_SET:
-#ifndef rtc_epoch
-		/*
-		 * There were no RTC clocks before 1900.
-		 */
-		if (arg < 1900) {
-			err = -EINVAL;
-			break;
-		}
-		rtc_epoch = arg;
-		err = 0;
-#endif
+	case RTC_IRQP_READ:
+		err = put_user(rtc->irq_freq, (unsigned long __user *)uarg);
 		break;
 
-	case RTC_EPOCH_READ:
-		err = put_user(rtc_epoch, (unsigned long __user *)uarg);
-		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(rtc, &alarm);
-		break;
+		return rtc_set_alarm(rtc, &alarm);
 
 	case RTC_WKALM_RD:
+		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;
-
-#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
-	case RTC_UIE_OFF:
-		clear_uie(rtc);
-		return 0;
+			err = -EFAULT;
+		return err;
 
-	case RTC_UIE_ON:
-		return set_uie(rtc);
-#endif
 	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);
 
-#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
-	clear_uie(rtc);
-#endif
 	if (rtc->ops->release)
 		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 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,
@@ -438,15 +464,12 @@ void rtc_dev_prepare(struct rtc_device *rtc)
 		return;
 
 	if (rtc->id >= RTC_DEV_MAX) {
-		pr_debug("%s: too many RTC devices\n", rtc->name);
+		dev_dbg(&rtc->dev, "%s: too many RTC devices\n", rtc->name);
 		return;
 	}
 
 	rtc->dev.devt = MKDEV(MAJOR(rtc_devt), rtc->id);
 
-	mutex_init(&rtc->char_lock);
-	spin_lock_init(&rtc->irq_lock);
-	init_waitqueue_head(&rtc->irq_queue);
 #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);
@@ -459,10 +482,10 @@ void rtc_dev_prepare(struct rtc_device *rtc)
 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",
+		dev_warn(&rtc->dev, "%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,
+		dev_dbg(&rtc->dev, "%s: dev (%d:%d)\n", rtc->name,
 			MAJOR(rtc_devt), rtc->id);
 }
 
@@ -478,8 +501,7 @@ void __init rtc_dev_init(void)
 
 	err = alloc_chrdev_region(&rtc_devt, 0, RTC_DEV_MAX, "rtc");
 	if (err < 0)
-		printk(KERN_ERR "%s: failed to allocate char dev region\n",
-			__FILE__);
+		pr_err("failed to allocate char dev region\n");
 }
 
 void __exit rtc_dev_exit(void)