xref: /openbmc/u-boot/drivers/timer/timer-uclass.c (revision 6b44ae6b)
1 /*
2  * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <timer.h>
11 
12 /*
13  * Implement a Timer uclass to work with lib/time.c. The timer is usually
14  * a 32 bits free-running up counter. The get_rate() method is used to get
15  * the input clock frequency of the timer. The get_count() method is used
16  * get the current 32 bits count value. If the hardware is counting down,
17  * the value should be inversed inside the method. There may be no real
18  * tick, and no timer interrupt.
19  */
20 
21 int timer_get_count(struct udevice *dev, unsigned long *count)
22 {
23 	const struct timer_ops *ops = device_get_ops(dev);
24 
25 	if (!ops->get_count)
26 		return -ENOSYS;
27 
28 	return ops->get_count(dev, count);
29 }
30 
31 unsigned long timer_get_rate(struct udevice *dev)
32 {
33 	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
34 
35 	return uc_priv->clock_rate;
36 }
37 
38 UCLASS_DRIVER(timer) = {
39 	.id		= UCLASS_TIMER,
40 	.name		= "timer",
41 	.per_device_auto_alloc_size = sizeof(struct timer_dev_priv),
42 };
43