From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030498AbWD1QQQ (ORCPT ); Fri, 28 Apr 2006 12:16:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030494AbWD1QQQ (ORCPT ); Fri, 28 Apr 2006 12:16:16 -0400 Received: from mba.ocn.ne.jp ([210.190.142.172]:25582 "EHLO smtp.mba.ocn.ne.jp") by vger.kernel.org with ESMTP id S1030492AbWD1QQP (ORCPT ); Fri, 28 Apr 2006 12:16:15 -0400 Date: Sat, 29 Apr 2006 01:16:48 +0900 (JST) Message-Id: <20060429.011648.25910123.anemo@mba.ocn.ne.jp> To: Alessandro Zummo Cc: linux-kernel@vger.kernel.org, akpm@osdl.org Subject: [PATCH] RTC: rtc-dev UIE emulation From: Atsushi Nemoto X-Fingerprint: 6ACA 1623 39BD 9A94 9B1A B746 CA77 FE94 2874 D52F X-Pgp-Public-Key: http://wwwkeys.pgp.net/pks/lookup?op=get&search=0x2874D52F X-Mailer: Mew version 3.3 on Emacs 21.4 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Import genrtc's RTC UIE emulation (CONFIG_GEN_RTC_X) to rtc-dev driver with slight adjustments. This makes UIE-less chips/drivers work better with programs doing read/poll on /dev/rtc, such as hwclock. Signed-off-by: Atsushi Nemoto diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 65d090d..29ca46c 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -73,6 +73,12 @@ config RTC_INTF_DEV This driver can also be built as a module. If so, the module will be called rtc-dev. +config RTC_INTF_DEV_X + bool "Extended RTC operation" + depends on RTC_INTF_DEV + help + Provides an emulation for RTC_UIE. + comment "RTC drivers" depends on RTC_CLASS diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c index b1e3e61..0bbd181 100644 --- a/drivers/rtc/rtc-dev.c +++ b/drivers/rtc/rtc-dev.c @@ -48,6 +48,93 @@ static int rtc_dev_open(struct inode *in return err; } +#ifdef CONFIG_RTC_INTF_DEV_X +/* + * 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(void *data) +{ + struct rtc_device *rtc = data; + struct rtc_time tm; + unsigned int tmp = rtc_read_time(&rtc->class_dev, &tm) ? 0 : tm.tm_sec; + int num = 0; + + spin_lock_irq(&rtc->irq_lock); + if (rtc->stop_rtc_timers) { + rtc->stask_active = 0; + spin_unlock_irq(&rtc->irq_lock); + return; + } + + if (rtc->oldsecs != tmp) { + num = (tmp + 60 - rtc->oldsecs) % 60; + rtc->oldsecs = tmp; + + rtc->timer_task.expires = jiffies + HZ - (HZ/10); + rtc->ttask_active = 1; + rtc->stask_active = 0; + add_timer(&rtc->timer_task); + } else if (schedule_work(&rtc->uie_task) == 0) + rtc->stask_active = 0; + spin_unlock_irq(&rtc->irq_lock); + if (num) + rtc_update_irq(&rtc->class_dev, num, RTC_UF | RTC_IRQF); +} + +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->ttask_active = 0; + rtc->stask_active = 1; + if ((schedule_work(&rtc->uie_task) == 0)) + rtc->stask_active = 0; + spin_unlock_irqrestore(&rtc->irq_lock, flags); +} + +static void clear_uie(struct rtc_device *rtc) +{ + spin_lock_irq(&rtc->irq_lock); + rtc->stop_rtc_timers = 1; + if (rtc->ttask_active) { + spin_unlock_irq(&rtc->irq_lock); + del_timer_sync(&rtc->timer_task); + spin_lock(&rtc->irq_lock); + rtc->ttask_active = 0; + } + while (rtc->stask_active) { + spin_unlock_irq(&rtc->irq_lock); + schedule(); + spin_lock_irq(&rtc->irq_lock); + } + rtc->irq_active = 0; + spin_unlock_irq(&rtc->irq_lock); +} + +static void set_uie(struct rtc_device *rtc) +{ + int start = 0; + spin_lock_irq(&rtc->irq_lock); + if (!rtc->irq_active) + start = rtc->irq_active = 1; + rtc->irq_data = 0; + spin_unlock_irq(&rtc->irq_lock); + if (start) { + struct rtc_time tm; + rtc->stop_rtc_timers = 0; + INIT_WORK(&rtc->uie_task, rtc_uie_task, rtc); + rtc->oldsecs = rtc_read_time(&rtc->class_dev, &tm) ? + 0 : tm.tm_sec; + setup_timer(&rtc->timer_task, rtc_uie_timer, + (unsigned long)rtc); + rtc->stask_active = 1; + if (schedule_work(&rtc->uie_task) == 0) + rtc->stask_active = 0; + } +} +#endif /* CONFIG_RTC_INTF_DEV_X */ static ssize_t rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) @@ -227,6 +314,15 @@ static int rtc_dev_ioctl(struct inode *i return -EFAULT; break; +#ifdef CONFIG_RTC_INTF_DEV_X + case RTC_UIE_OFF: + clear_uie(rtc); + return 0; + + case RTC_UIE_ON: + set_uie(rtc); + return 0; +#endif default: err = -EINVAL; break; @@ -239,6 +335,9 @@ static int rtc_dev_release(struct inode { struct rtc_device *rtc = to_rtc_device(file->private_data); +#ifdef CONFIG_RTC_INTF_DEV_X + clear_uie(rtc); +#endif if (rtc->ops->release) rtc->ops->release(rtc->class_dev.dev); diff --git a/include/linux/rtc.h b/include/linux/rtc.h index ab61cd1..29199c3 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -155,6 +155,15 @@ struct rtc_device struct rtc_task *irq_task; spinlock_t irq_task_lock; int irq_freq; +#ifdef CONFIG_RTC_INTF_DEV_X + struct work_struct uie_task; + struct timer_list timer_task; + unsigned int oldsecs; + unsigned int irq_active :1; + unsigned int stop_rtc_timers :1; /* don't requeue tasks */ + unsigned int stask_active :1; /* schedule_work */ + unsigned int ttask_active :1; /* timer_task */ +#endif }; #define to_rtc_device(d) container_of(d, struct rtc_device, class_dev)