2 * Copyright (C) 2014 Samsung Electronics Co., Ltd.
3 * Sylwester Nawrocki <s.nawrocki@samsung.com>
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.
10 #include <linux/clk.h>
11 #include <linux/clk-provider.h>
12 #include <linux/clk/clk-conf.h>
13 #include <linux/device.h>
15 #include <linux/printk.h>
17 static int __set_clk_parents(struct device_node *node, bool clk_supplier)
19 struct of_phandle_args clkspec;
20 int index, rc, num_parents;
21 struct clk *clk, *pclk;
23 num_parents = of_count_phandle_with_args(node, "assigned-clock-parents",
25 if (num_parents == -EINVAL)
26 pr_err("clk: invalid value of clock-parents property at %s\n",
29 for (index = 0; index < num_parents; index++) {
30 rc = of_parse_phandle_with_args(node, "assigned-clock-parents",
31 "#clock-cells", index, &clkspec);
33 /* skip empty (null) phandles */
39 if (clkspec.np == node && !clk_supplier)
41 pclk = of_clk_get_from_provider(&clkspec);
43 pr_warn("clk: couldn't get parent clock %d for %s\n",
44 index, node->full_name);
48 rc = of_parse_phandle_with_args(node, "assigned-clocks",
49 "#clock-cells", index, &clkspec);
52 if (clkspec.np == node && !clk_supplier) {
56 clk = of_clk_get_from_provider(&clkspec);
58 pr_warn("clk: couldn't get parent clock %d for %s\n",
59 index, node->full_name);
64 rc = clk_set_parent(clk, pclk);
66 pr_err("clk: failed to reparent %s to %s: %d\n",
67 __clk_get_name(clk), __clk_get_name(pclk), rc);
77 static int __set_clk_rates(struct device_node *node, bool clk_supplier)
79 struct of_phandle_args clkspec;
80 struct property *prop;
86 of_property_for_each_u32(node, "assigned-clock-rates", prop, cur, rate) {
88 rc = of_parse_phandle_with_args(node, "assigned-clocks",
89 "#clock-cells", index, &clkspec);
91 /* skip empty (null) phandles */
97 if (clkspec.np == node && !clk_supplier)
100 clk = of_clk_get_from_provider(&clkspec);
102 pr_warn("clk: couldn't get clock %d for %s\n",
103 index, node->full_name);
107 rc = clk_set_rate(clk, rate);
109 pr_err("clk: couldn't set %s clock rate: %d\n",
110 __clk_get_name(clk), rc);
119 * of_clk_set_defaults() - parse and set assigned clocks configuration
120 * @node: device node to apply clock settings for
121 * @clk_supplier: true if clocks supplied by @node should also be considered
123 * This function parses 'assigned-{clocks/clock-parents/clock-rates}' properties
124 * and sets any specified clock parents and rates. The @clk_supplier argument
125 * should be set to true if @node may be also a clock supplier of any clock
126 * listed in its 'assigned-clocks' or 'assigned-clock-parents' properties.
127 * If @clk_supplier is false the function exits returnning 0 as soon as it
128 * determines the @node is also a supplier of any of the clocks.
130 int of_clk_set_defaults(struct device_node *node, bool clk_supplier)
137 rc = __set_clk_parents(node, clk_supplier);
141 return __set_clk_rates(node, clk_supplier);
143 EXPORT_SYMBOL_GPL(of_clk_set_defaults);