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 mux_hw
->clk
= hw
->clk
;
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 mux_hw
->clk
= hw
->clk
;
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 rate_hw
->clk
= hw
->clk
;
55 return rate_ops
->recalc_rate(rate_hw
, parent_rate
);
58 static long clk_composite_determine_rate(struct clk_hw
*hw
, unsigned long rate
,
59 unsigned long *best_parent_rate
,
60 struct clk
**best_parent_p
)
62 struct clk_composite
*composite
= to_clk_composite(hw
);
63 const struct clk_ops
*rate_ops
= composite
->rate_ops
;
64 const struct clk_ops
*mux_ops
= composite
->mux_ops
;
65 struct clk_hw
*rate_hw
= composite
->rate_hw
;
66 struct clk_hw
*mux_hw
= composite
->mux_hw
;
68 unsigned long parent_rate
;
69 long tmp_rate
, best_rate
= 0;
70 unsigned long rate_diff
;
71 unsigned long best_rate_diff
= ULONG_MAX
;
74 if (rate_hw
&& rate_ops
&& rate_ops
->determine_rate
) {
75 rate_hw
->clk
= hw
->clk
;
76 return rate_ops
->determine_rate(rate_hw
, rate
, best_parent_rate
,
78 } else if (rate_hw
&& rate_ops
&& rate_ops
->round_rate
&&
79 mux_hw
&& mux_ops
&& mux_ops
->set_parent
) {
80 *best_parent_p
= NULL
;
82 if (__clk_get_flags(hw
->clk
) & CLK_SET_RATE_NO_REPARENT
) {
83 *best_parent_p
= clk_get_parent(mux_hw
->clk
);
84 *best_parent_rate
= __clk_get_rate(*best_parent_p
);
86 return rate_ops
->round_rate(rate_hw
, rate
,
90 for (i
= 0; i
< __clk_get_num_parents(mux_hw
->clk
); i
++) {
91 parent
= clk_get_parent_by_index(mux_hw
->clk
, i
);
95 parent_rate
= __clk_get_rate(parent
);
97 tmp_rate
= rate_ops
->round_rate(rate_hw
, rate
,
102 rate_diff
= abs(rate
- tmp_rate
);
104 if (!rate_diff
|| !*best_parent_p
105 || best_rate_diff
> rate_diff
) {
106 *best_parent_p
= parent
;
107 *best_parent_rate
= parent_rate
;
108 best_rate_diff
= rate_diff
;
109 best_rate
= tmp_rate
;
117 } else if (mux_hw
&& mux_ops
&& mux_ops
->determine_rate
) {
118 mux_hw
->clk
= hw
->clk
;
119 return mux_ops
->determine_rate(mux_hw
, rate
, best_parent_rate
,
122 pr_err("clk: clk_composite_determine_rate function called, but no mux or rate callback set!\n");
127 static long clk_composite_round_rate(struct clk_hw
*hw
, unsigned long rate
,
128 unsigned long *prate
)
130 struct clk_composite
*composite
= to_clk_composite(hw
);
131 const struct clk_ops
*rate_ops
= composite
->rate_ops
;
132 struct clk_hw
*rate_hw
= composite
->rate_hw
;
134 rate_hw
->clk
= hw
->clk
;
136 return rate_ops
->round_rate(rate_hw
, rate
, prate
);
139 static int clk_composite_set_rate(struct clk_hw
*hw
, unsigned long rate
,
140 unsigned long parent_rate
)
142 struct clk_composite
*composite
= to_clk_composite(hw
);
143 const struct clk_ops
*rate_ops
= composite
->rate_ops
;
144 struct clk_hw
*rate_hw
= composite
->rate_hw
;
146 rate_hw
->clk
= hw
->clk
;
148 return rate_ops
->set_rate(rate_hw
, rate
, parent_rate
);
151 static int clk_composite_is_enabled(struct clk_hw
*hw
)
153 struct clk_composite
*composite
= to_clk_composite(hw
);
154 const struct clk_ops
*gate_ops
= composite
->gate_ops
;
155 struct clk_hw
*gate_hw
= composite
->gate_hw
;
157 gate_hw
->clk
= hw
->clk
;
159 return gate_ops
->is_enabled(gate_hw
);
162 static int clk_composite_enable(struct clk_hw
*hw
)
164 struct clk_composite
*composite
= to_clk_composite(hw
);
165 const struct clk_ops
*gate_ops
= composite
->gate_ops
;
166 struct clk_hw
*gate_hw
= composite
->gate_hw
;
168 gate_hw
->clk
= hw
->clk
;
170 return gate_ops
->enable(gate_hw
);
173 static void clk_composite_disable(struct clk_hw
*hw
)
175 struct clk_composite
*composite
= to_clk_composite(hw
);
176 const struct clk_ops
*gate_ops
= composite
->gate_ops
;
177 struct clk_hw
*gate_hw
= composite
->gate_hw
;
179 gate_hw
->clk
= hw
->clk
;
181 gate_ops
->disable(gate_hw
);
184 struct clk
*clk_register_composite(struct device
*dev
, const char *name
,
185 const char **parent_names
, int num_parents
,
186 struct clk_hw
*mux_hw
, const struct clk_ops
*mux_ops
,
187 struct clk_hw
*rate_hw
, const struct clk_ops
*rate_ops
,
188 struct clk_hw
*gate_hw
, const struct clk_ops
*gate_ops
,
192 struct clk_init_data init
;
193 struct clk_composite
*composite
;
194 struct clk_ops
*clk_composite_ops
;
196 composite
= kzalloc(sizeof(*composite
), GFP_KERNEL
);
198 pr_err("%s: could not allocate composite clk\n", __func__
);
199 return ERR_PTR(-ENOMEM
);
203 init
.flags
= flags
| CLK_IS_BASIC
;
204 init
.parent_names
= parent_names
;
205 init
.num_parents
= num_parents
;
207 clk_composite_ops
= &composite
->ops
;
209 if (mux_hw
&& mux_ops
) {
210 if (!mux_ops
->get_parent
) {
211 clk
= ERR_PTR(-EINVAL
);
215 composite
->mux_hw
= mux_hw
;
216 composite
->mux_ops
= mux_ops
;
217 clk_composite_ops
->get_parent
= clk_composite_get_parent
;
218 if (mux_ops
->set_parent
)
219 clk_composite_ops
->set_parent
= clk_composite_set_parent
;
220 if (mux_ops
->determine_rate
)
221 clk_composite_ops
->determine_rate
= clk_composite_determine_rate
;
224 if (rate_hw
&& rate_ops
) {
225 if (!rate_ops
->recalc_rate
) {
226 clk
= ERR_PTR(-EINVAL
);
229 clk_composite_ops
->recalc_rate
= clk_composite_recalc_rate
;
231 if (rate_ops
->determine_rate
)
232 clk_composite_ops
->determine_rate
=
233 clk_composite_determine_rate
;
234 else if (rate_ops
->round_rate
)
235 clk_composite_ops
->round_rate
=
236 clk_composite_round_rate
;
238 /* .set_rate requires either .round_rate or .determine_rate */
239 if (rate_ops
->set_rate
) {
240 if (rate_ops
->determine_rate
|| rate_ops
->round_rate
)
241 clk_composite_ops
->set_rate
=
242 clk_composite_set_rate
;
244 WARN(1, "%s: missing round_rate op is required\n",
248 composite
->rate_hw
= rate_hw
;
249 composite
->rate_ops
= rate_ops
;
252 if (gate_hw
&& gate_ops
) {
253 if (!gate_ops
->is_enabled
|| !gate_ops
->enable
||
254 !gate_ops
->disable
) {
255 clk
= ERR_PTR(-EINVAL
);
259 composite
->gate_hw
= gate_hw
;
260 composite
->gate_ops
= gate_ops
;
261 clk_composite_ops
->is_enabled
= clk_composite_is_enabled
;
262 clk_composite_ops
->enable
= clk_composite_enable
;
263 clk_composite_ops
->disable
= clk_composite_disable
;
266 init
.ops
= clk_composite_ops
;
267 composite
->hw
.init
= &init
;
269 clk
= clk_register(dev
, &composite
->hw
);
273 if (composite
->mux_hw
)
274 composite
->mux_hw
->clk
= clk
;
276 if (composite
->rate_hw
)
277 composite
->rate_hw
->clk
= clk
;
279 if (composite
->gate_hw
)
280 composite
->gate_hw
->clk
= clk
;