2 * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
3 * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * Fixed rate clock implementation
12 #include <linux/clk-provider.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
16 #include <linux/err.h>
19 * DOC: basic fixed-rate clock that cannot gate
21 * Traits of this clock:
22 * prepare - clk_(un)prepare only ensures parents are prepared
23 * enable - clk_enable only ensures parents are enabled
24 * rate - rate is always a fixed value. No clk_set_rate support
25 * parent - fixed parent. No clk_set_parent support
28 #define to_clk_fixed_rate(_hw) container_of(_hw, struct clk_fixed_rate, hw)
30 static unsigned long clk_fixed_rate_recalc_rate(struct clk_hw *hw,
31 unsigned long parent_rate)
33 return to_clk_fixed_rate(hw)->fixed_rate;
36 const struct clk_ops clk_fixed_rate_ops = {
37 .recalc_rate = clk_fixed_rate_recalc_rate,
39 EXPORT_SYMBOL_GPL(clk_fixed_rate_ops);
41 struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
42 const char *parent_name, unsigned long flags,
43 unsigned long fixed_rate)
45 struct clk_fixed_rate *fixed;
46 char **parent_names = NULL;
49 fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL);
52 pr_err("%s: could not allocate fixed clk\n", __func__);
53 return ERR_PTR(-ENOMEM);
56 /* struct clk_fixed_rate assignments */
57 fixed->fixed_rate = fixed_rate;
60 parent_names = kmalloc(sizeof(char *), GFP_KERNEL);
65 len = sizeof(char) * strlen(parent_name);
67 parent_names[0] = kmalloc(len, GFP_KERNEL);
72 strncpy(parent_names[0], parent_name, len);
76 return clk_register(dev, name,
77 &clk_fixed_rate_ops, &fixed->hw,
79 (parent_name ? 1 : 0),