2 * Copyright (c) 2013 NVIDIA CORPORATION. All rights reserved.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 #include <linux/clk.h>
18 #include <linux/clk-provider.h>
19 #include <linux/err.h>
20 #include <linux/slab.h>
22 #define to_clk_composite(_hw) container_of(_hw, struct clk_composite, hw)
24 static u8 clk_composite_get_parent(struct clk_hw *hw)
26 struct clk_composite *composite = to_clk_composite(hw);
27 const struct clk_ops *mux_ops = composite->mux_ops;
28 struct clk_hw *mux_hw = composite->mux_hw;
30 __clk_hw_set_clk(mux_hw, hw);
32 return mux_ops->get_parent(mux_hw);
35 static int clk_composite_set_parent(struct clk_hw *hw, u8 index)
37 struct clk_composite *composite = to_clk_composite(hw);
38 const struct clk_ops *mux_ops = composite->mux_ops;
39 struct clk_hw *mux_hw = composite->mux_hw;
41 __clk_hw_set_clk(mux_hw, hw);
43 return mux_ops->set_parent(mux_hw, index);
46 static unsigned long clk_composite_recalc_rate(struct clk_hw *hw,
47 unsigned long parent_rate)
49 struct clk_composite *composite = to_clk_composite(hw);
50 const struct clk_ops *rate_ops = composite->rate_ops;
51 struct clk_hw *rate_hw = composite->rate_hw;
53 __clk_hw_set_clk(rate_hw, hw);
55 return rate_ops->recalc_rate(rate_hw, parent_rate);
58 static int clk_composite_determine_rate(struct clk_hw *hw,
59 struct clk_rate_request *req)
61 struct clk_composite *composite = to_clk_composite(hw);
62 const struct clk_ops *rate_ops = composite->rate_ops;
63 const struct clk_ops *mux_ops = composite->mux_ops;
64 struct clk_hw *rate_hw = composite->rate_hw;
65 struct clk_hw *mux_hw = composite->mux_hw;
66 struct clk_hw *parent;
67 unsigned long parent_rate;
68 long tmp_rate, best_rate = 0;
69 unsigned long rate_diff;
70 unsigned long best_rate_diff = ULONG_MAX;
74 if (rate_hw && rate_ops && rate_ops->determine_rate) {
75 __clk_hw_set_clk(rate_hw, hw);
76 return rate_ops->determine_rate(rate_hw, req);
77 } else if (rate_hw && rate_ops && rate_ops->round_rate &&
78 mux_hw && mux_ops && mux_ops->set_parent) {
79 req->best_parent_hw = NULL;
81 if (clk_hw_get_flags(hw) & CLK_SET_RATE_NO_REPARENT) {
82 parent = clk_hw_get_parent(mux_hw);
83 req->best_parent_hw = parent;
84 req->best_parent_rate = clk_hw_get_rate(parent);
86 rate = rate_ops->round_rate(rate_hw, req->rate,
87 &req->best_parent_rate);
95 for (i = 0; i < clk_hw_get_num_parents(mux_hw); i++) {
96 parent = clk_hw_get_parent_by_index(mux_hw, i);
100 parent_rate = clk_hw_get_rate(parent);
102 tmp_rate = rate_ops->round_rate(rate_hw, req->rate,
107 rate_diff = abs(req->rate - tmp_rate);
109 if (!rate_diff || !req->best_parent_hw
110 || best_rate_diff > rate_diff) {
111 req->best_parent_hw = parent;
112 req->best_parent_rate = parent_rate;
113 best_rate_diff = rate_diff;
114 best_rate = tmp_rate;
121 req->rate = best_rate;
123 } else if (mux_hw && mux_ops && mux_ops->determine_rate) {
124 __clk_hw_set_clk(mux_hw, hw);
125 return mux_ops->determine_rate(mux_hw, req);
127 pr_err("clk: clk_composite_determine_rate function called, but no mux or rate callback set!\n");
132 static long clk_composite_round_rate(struct clk_hw *hw, unsigned long rate,
133 unsigned long *prate)
135 struct clk_composite *composite = to_clk_composite(hw);
136 const struct clk_ops *rate_ops = composite->rate_ops;
137 struct clk_hw *rate_hw = composite->rate_hw;
139 __clk_hw_set_clk(rate_hw, hw);
141 return rate_ops->round_rate(rate_hw, rate, prate);
144 static int clk_composite_set_rate(struct clk_hw *hw, unsigned long rate,
145 unsigned long parent_rate)
147 struct clk_composite *composite = to_clk_composite(hw);
148 const struct clk_ops *rate_ops = composite->rate_ops;
149 struct clk_hw *rate_hw = composite->rate_hw;
151 __clk_hw_set_clk(rate_hw, hw);
153 return rate_ops->set_rate(rate_hw, rate, parent_rate);
156 static int clk_composite_set_rate_and_parent(struct clk_hw *hw,
158 unsigned long parent_rate,
161 struct clk_composite *composite = to_clk_composite(hw);
162 const struct clk_ops *rate_ops = composite->rate_ops;
163 const struct clk_ops *mux_ops = composite->mux_ops;
164 struct clk_hw *rate_hw = composite->rate_hw;
165 struct clk_hw *mux_hw = composite->mux_hw;
166 unsigned long temp_rate;
168 __clk_hw_set_clk(rate_hw, hw);
169 __clk_hw_set_clk(mux_hw, hw);
171 temp_rate = rate_ops->recalc_rate(rate_hw, parent_rate);
172 if (temp_rate > rate) {
173 rate_ops->set_rate(rate_hw, rate, parent_rate);
174 mux_ops->set_parent(mux_hw, index);
176 mux_ops->set_parent(mux_hw, index);
177 rate_ops->set_rate(rate_hw, rate, parent_rate);
183 static int clk_composite_is_enabled(struct clk_hw *hw)
185 struct clk_composite *composite = to_clk_composite(hw);
186 const struct clk_ops *gate_ops = composite->gate_ops;
187 struct clk_hw *gate_hw = composite->gate_hw;
189 __clk_hw_set_clk(gate_hw, hw);
191 return gate_ops->is_enabled(gate_hw);
194 static int clk_composite_enable(struct clk_hw *hw)
196 struct clk_composite *composite = to_clk_composite(hw);
197 const struct clk_ops *gate_ops = composite->gate_ops;
198 struct clk_hw *gate_hw = composite->gate_hw;
200 __clk_hw_set_clk(gate_hw, hw);
202 return gate_ops->enable(gate_hw);
205 static void clk_composite_disable(struct clk_hw *hw)
207 struct clk_composite *composite = to_clk_composite(hw);
208 const struct clk_ops *gate_ops = composite->gate_ops;
209 struct clk_hw *gate_hw = composite->gate_hw;
211 __clk_hw_set_clk(gate_hw, hw);
213 gate_ops->disable(gate_hw);
216 struct clk *clk_register_composite(struct device *dev, const char *name,
217 const char * const *parent_names, int num_parents,
218 struct clk_hw *mux_hw, const struct clk_ops *mux_ops,
219 struct clk_hw *rate_hw, const struct clk_ops *rate_ops,
220 struct clk_hw *gate_hw, const struct clk_ops *gate_ops,
224 struct clk_init_data init;
225 struct clk_composite *composite;
226 struct clk_ops *clk_composite_ops;
228 composite = kzalloc(sizeof(*composite), GFP_KERNEL);
230 return ERR_PTR(-ENOMEM);
233 init.flags = flags | CLK_IS_BASIC;
234 init.parent_names = parent_names;
235 init.num_parents = num_parents;
237 clk_composite_ops = &composite->ops;
239 if (mux_hw && mux_ops) {
240 if (!mux_ops->get_parent) {
241 clk = ERR_PTR(-EINVAL);
245 composite->mux_hw = mux_hw;
246 composite->mux_ops = mux_ops;
247 clk_composite_ops->get_parent = clk_composite_get_parent;
248 if (mux_ops->set_parent)
249 clk_composite_ops->set_parent = clk_composite_set_parent;
250 if (mux_ops->determine_rate)
251 clk_composite_ops->determine_rate = clk_composite_determine_rate;
254 if (rate_hw && rate_ops) {
255 if (!rate_ops->recalc_rate) {
256 clk = ERR_PTR(-EINVAL);
259 clk_composite_ops->recalc_rate = clk_composite_recalc_rate;
261 if (rate_ops->determine_rate)
262 clk_composite_ops->determine_rate =
263 clk_composite_determine_rate;
264 else if (rate_ops->round_rate)
265 clk_composite_ops->round_rate =
266 clk_composite_round_rate;
268 /* .set_rate requires either .round_rate or .determine_rate */
269 if (rate_ops->set_rate) {
270 if (rate_ops->determine_rate || rate_ops->round_rate)
271 clk_composite_ops->set_rate =
272 clk_composite_set_rate;
274 WARN(1, "%s: missing round_rate op is required\n",
278 composite->rate_hw = rate_hw;
279 composite->rate_ops = rate_ops;
282 if (mux_hw && mux_ops && rate_hw && rate_ops) {
283 if (mux_ops->set_parent && rate_ops->set_rate)
284 clk_composite_ops->set_rate_and_parent =
285 clk_composite_set_rate_and_parent;
288 if (gate_hw && gate_ops) {
289 if (!gate_ops->is_enabled || !gate_ops->enable ||
290 !gate_ops->disable) {
291 clk = ERR_PTR(-EINVAL);
295 composite->gate_hw = gate_hw;
296 composite->gate_ops = gate_ops;
297 clk_composite_ops->is_enabled = clk_composite_is_enabled;
298 clk_composite_ops->enable = clk_composite_enable;
299 clk_composite_ops->disable = clk_composite_disable;
302 init.ops = clk_composite_ops;
303 composite->hw.init = &init;
305 clk = clk_register(dev, &composite->hw);
309 if (composite->mux_hw)
310 composite->mux_hw->clk = clk;
312 if (composite->rate_hw)
313 composite->rate_hw->clk = clk;
315 if (composite->gate_hw)
316 composite->gate_hw->clk = clk;