1*c8a7ba9eSThomas Chou /* 2*c8a7ba9eSThomas Chou * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw> 3*c8a7ba9eSThomas Chou * 4*c8a7ba9eSThomas Chou * SPDX-License-Identifier: GPL-2.0+ 5*c8a7ba9eSThomas Chou */ 6*c8a7ba9eSThomas Chou 7*c8a7ba9eSThomas Chou #include <common.h> 8*c8a7ba9eSThomas Chou #include <dm.h> 9*c8a7ba9eSThomas Chou #include <errno.h> 10*c8a7ba9eSThomas Chou #include <timer.h> 11*c8a7ba9eSThomas Chou 12*c8a7ba9eSThomas Chou /* 13*c8a7ba9eSThomas Chou * Implement a Timer uclass to work with lib/time.c. The timer is usually 14*c8a7ba9eSThomas Chou * a 32 bits free-running up counter. The get_rate() method is used to get 15*c8a7ba9eSThomas Chou * the input clock frequency of the timer. The get_count() method is used 16*c8a7ba9eSThomas Chou * get the current 32 bits count value. If the hardware is counting down, 17*c8a7ba9eSThomas Chou * the value should be inversed inside the method. There may be no real 18*c8a7ba9eSThomas Chou * tick, and no timer interrupt. 19*c8a7ba9eSThomas Chou */ 20*c8a7ba9eSThomas Chou 21*c8a7ba9eSThomas Chou int timer_get_count(struct udevice *dev, unsigned long *count) 22*c8a7ba9eSThomas Chou { 23*c8a7ba9eSThomas Chou const struct timer_ops *ops = device_get_ops(dev); 24*c8a7ba9eSThomas Chou 25*c8a7ba9eSThomas Chou if (!ops->get_count) 26*c8a7ba9eSThomas Chou return -ENOSYS; 27*c8a7ba9eSThomas Chou 28*c8a7ba9eSThomas Chou return ops->get_count(dev, count); 29*c8a7ba9eSThomas Chou } 30*c8a7ba9eSThomas Chou 31*c8a7ba9eSThomas Chou unsigned long timer_get_rate(struct udevice *dev) 32*c8a7ba9eSThomas Chou { 33*c8a7ba9eSThomas Chou struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); 34*c8a7ba9eSThomas Chou 35*c8a7ba9eSThomas Chou return uc_priv->clock_rate; 36*c8a7ba9eSThomas Chou } 37*c8a7ba9eSThomas Chou 38*c8a7ba9eSThomas Chou UCLASS_DRIVER(timer) = { 39*c8a7ba9eSThomas Chou .id = UCLASS_TIMER, 40*c8a7ba9eSThomas Chou .name = "timer", 41*c8a7ba9eSThomas Chou .per_device_auto_alloc_size = sizeof(struct timer_dev_priv), 42*c8a7ba9eSThomas Chou }; 43