diff options
Diffstat (limited to 'drivers/rtc/rtc-dev.c')
-rw-r--r-- | drivers/rtc/rtc-dev.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-dev.c b/drivers/rtc/rtc-dev.c index 37c3cc1b3dd5..d0e06edb14c5 100644 --- a/drivers/rtc/rtc-dev.c +++ b/drivers/rtc/rtc-dev.c | |||
@@ -46,6 +46,105 @@ static int rtc_dev_open(struct inode *inode, struct file *file) | |||
46 | return err; | 46 | return err; |
47 | } | 47 | } |
48 | 48 | ||
49 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL | ||
50 | /* | ||
51 | * Routine to poll RTC seconds field for change as often as possible, | ||
52 | * after first RTC_UIE use timer to reduce polling | ||
53 | */ | ||
54 | static void rtc_uie_task(struct work_struct *work) | ||
55 | { | ||
56 | struct rtc_device *rtc = | ||
57 | container_of(work, struct rtc_device, uie_task); | ||
58 | struct rtc_time tm; | ||
59 | int num = 0; | ||
60 | int err; | ||
61 | |||
62 | err = rtc_read_time(rtc, &tm); | ||
63 | |||
64 | spin_lock_irq(&rtc->irq_lock); | ||
65 | if (rtc->stop_uie_polling || err) { | ||
66 | rtc->uie_task_active = 0; | ||
67 | } else if (rtc->oldsecs != tm.tm_sec) { | ||
68 | num = (tm.tm_sec + 60 - rtc->oldsecs) % 60; | ||
69 | rtc->oldsecs = tm.tm_sec; | ||
70 | rtc->uie_timer.expires = jiffies + HZ - (HZ/10); | ||
71 | rtc->uie_timer_active = 1; | ||
72 | rtc->uie_task_active = 0; | ||
73 | add_timer(&rtc->uie_timer); | ||
74 | } else if (schedule_work(&rtc->uie_task) == 0) { | ||
75 | rtc->uie_task_active = 0; | ||
76 | } | ||
77 | spin_unlock_irq(&rtc->irq_lock); | ||
78 | if (num) | ||
79 | rtc_handle_legacy_irq(rtc, num, RTC_UF); | ||
80 | } | ||
81 | static void rtc_uie_timer(unsigned long data) | ||
82 | { | ||
83 | struct rtc_device *rtc = (struct rtc_device *)data; | ||
84 | unsigned long flags; | ||
85 | |||
86 | spin_lock_irqsave(&rtc->irq_lock, flags); | ||
87 | rtc->uie_timer_active = 0; | ||
88 | rtc->uie_task_active = 1; | ||
89 | if ((schedule_work(&rtc->uie_task) == 0)) | ||
90 | rtc->uie_task_active = 0; | ||
91 | spin_unlock_irqrestore(&rtc->irq_lock, flags); | ||
92 | } | ||
93 | |||
94 | static int clear_uie(struct rtc_device *rtc) | ||
95 | { | ||
96 | spin_lock_irq(&rtc->irq_lock); | ||
97 | if (rtc->uie_irq_active) { | ||
98 | rtc->stop_uie_polling = 1; | ||
99 | if (rtc->uie_timer_active) { | ||
100 | spin_unlock_irq(&rtc->irq_lock); | ||
101 | del_timer_sync(&rtc->uie_timer); | ||
102 | spin_lock_irq(&rtc->irq_lock); | ||
103 | rtc->uie_timer_active = 0; | ||
104 | } | ||
105 | if (rtc->uie_task_active) { | ||
106 | spin_unlock_irq(&rtc->irq_lock); | ||
107 | flush_scheduled_work(); | ||
108 | spin_lock_irq(&rtc->irq_lock); | ||
109 | } | ||
110 | rtc->uie_irq_active = 0; | ||
111 | } | ||
112 | spin_unlock_irq(&rtc->irq_lock); | ||
113 | return 0; | ||
114 | } | ||
115 | |||
116 | static int set_uie(struct rtc_device *rtc) | ||
117 | { | ||
118 | struct rtc_time tm; | ||
119 | int err; | ||
120 | |||
121 | err = rtc_read_time(rtc, &tm); | ||
122 | if (err) | ||
123 | return err; | ||
124 | spin_lock_irq(&rtc->irq_lock); | ||
125 | if (!rtc->uie_irq_active) { | ||
126 | rtc->uie_irq_active = 1; | ||
127 | rtc->stop_uie_polling = 0; | ||
128 | rtc->oldsecs = tm.tm_sec; | ||
129 | rtc->uie_task_active = 1; | ||
130 | if (schedule_work(&rtc->uie_task) == 0) | ||
131 | rtc->uie_task_active = 0; | ||
132 | } | ||
133 | rtc->irq_data = 0; | ||
134 | spin_unlock_irq(&rtc->irq_lock); | ||
135 | return 0; | ||
136 | } | ||
137 | |||
138 | int rtc_dev_update_irq_enable_emul(struct rtc_device *rtc, unsigned int enabled) | ||
139 | { | ||
140 | if (enabled) | ||
141 | return set_uie(rtc); | ||
142 | else | ||
143 | return clear_uie(rtc); | ||
144 | } | ||
145 | EXPORT_SYMBOL(rtc_dev_update_irq_enable_emul); | ||
146 | |||
147 | #endif /* CONFIG_RTC_INTF_DEV_UIE_EMUL */ | ||
49 | 148 | ||
50 | static ssize_t | 149 | static ssize_t |
51 | rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | 150 | rtc_dev_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) |
@@ -387,6 +486,11 @@ void rtc_dev_prepare(struct rtc_device *rtc) | |||
387 | 486 | ||
388 | rtc->dev.devt = MKDEV(MAJOR(rtc_devt), rtc->id); | 487 | rtc->dev.devt = MKDEV(MAJOR(rtc_devt), rtc->id); |
389 | 488 | ||
489 | #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL | ||
490 | INIT_WORK(&rtc->uie_task, rtc_uie_task); | ||
491 | setup_timer(&rtc->uie_timer, rtc_uie_timer, (unsigned long)rtc); | ||
492 | #endif | ||
493 | |||
390 | cdev_init(&rtc->char_dev, &rtc_dev_fops); | 494 | cdev_init(&rtc->char_dev, &rtc_dev_fops); |
391 | rtc->char_dev.owner = rtc->owner; | 495 | rtc->char_dev.owner = rtc->owner; |
392 | } | 496 | } |