xref: /rk3399_rockchip-uboot/drivers/timer/timer-uclass.c (revision 435ae76edd3a90fc4dd2f582052d7362cb8bdad7)
1c8a7ba9eSThomas Chou /*
2c8a7ba9eSThomas Chou  * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
3c8a7ba9eSThomas Chou  *
4c8a7ba9eSThomas Chou  * SPDX-License-Identifier:	GPL-2.0+
5c8a7ba9eSThomas Chou  */
6c8a7ba9eSThomas Chou 
7c8a7ba9eSThomas Chou #include <common.h>
8c8a7ba9eSThomas Chou #include <dm.h>
9c8a7ba9eSThomas Chou #include <errno.h>
10c8a7ba9eSThomas Chou #include <timer.h>
11c8a7ba9eSThomas Chou 
12c8a7ba9eSThomas Chou /*
13*435ae76eSBin Meng  * Implement a timer uclass to work with lib/time.c. The timer is usually
14c8a7ba9eSThomas Chou  * a 32 bits free-running up counter. The get_rate() method is used to get
15c8a7ba9eSThomas Chou  * the input clock frequency of the timer. The get_count() method is used
16*435ae76eSBin Meng  * to get the current 32 bits count value. If the hardware is counting down,
17c8a7ba9eSThomas Chou  * the value should be inversed inside the method. There may be no real
18c8a7ba9eSThomas Chou  * tick, and no timer interrupt.
19c8a7ba9eSThomas Chou  */
20c8a7ba9eSThomas Chou 
21c8a7ba9eSThomas Chou int timer_get_count(struct udevice *dev, unsigned long *count)
22c8a7ba9eSThomas Chou {
23c8a7ba9eSThomas Chou 	const struct timer_ops *ops = device_get_ops(dev);
24c8a7ba9eSThomas Chou 
25c8a7ba9eSThomas Chou 	if (!ops->get_count)
26c8a7ba9eSThomas Chou 		return -ENOSYS;
27c8a7ba9eSThomas Chou 
28c8a7ba9eSThomas Chou 	return ops->get_count(dev, count);
29c8a7ba9eSThomas Chou }
30c8a7ba9eSThomas Chou 
31c8a7ba9eSThomas Chou unsigned long timer_get_rate(struct udevice *dev)
32c8a7ba9eSThomas Chou {
33c8a7ba9eSThomas Chou 	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
34c8a7ba9eSThomas Chou 
35c8a7ba9eSThomas Chou 	return uc_priv->clock_rate;
36c8a7ba9eSThomas Chou }
37c8a7ba9eSThomas Chou 
38c8a7ba9eSThomas Chou UCLASS_DRIVER(timer) = {
39c8a7ba9eSThomas Chou 	.id		= UCLASS_TIMER,
40c8a7ba9eSThomas Chou 	.name		= "timer",
41c8a7ba9eSThomas Chou 	.per_device_auto_alloc_size = sizeof(struct timer_dev_priv),
42c8a7ba9eSThomas Chou };
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