Commit | Line | Data |
---|---|---|
0318e693 | 1 | /* |
6d803ba7 | 2 | * drivers/clk/clkdev.c |
0318e693 RK |
3 | * |
4 | * Copyright (C) 2008 Russell King. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * Helper for the clk API to assist looking up a struct clk. | |
11 | */ | |
12 | #include <linux/module.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/device.h> | |
15 | #include <linux/list.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/err.h> | |
18 | #include <linux/string.h> | |
19 | #include <linux/mutex.h> | |
c0c60c4b | 20 | #include <linux/clk.h> |
6d803ba7 | 21 | #include <linux/clkdev.h> |
0318e693 RK |
22 | |
23 | static LIST_HEAD(clocks); | |
24 | static DEFINE_MUTEX(clocks_mutex); | |
25 | ||
409dc360 RK |
26 | /* |
27 | * Find the correct struct clk for the device and connection ID. | |
28 | * We do slightly fuzzy matching here: | |
29 | * An entry with a NULL ID is assumed to be a wildcard. | |
30 | * If an entry has a device ID, it must match | |
31 | * If an entry has a connection ID, it must match | |
32 | * Then we take the most specific entry - with the following | |
659431fc | 33 | * order of precedence: dev+con > dev only > con only. |
409dc360 | 34 | */ |
e8bf8df9 | 35 | static struct clk_lookup *clk_find(const char *dev_id, const char *con_id) |
0318e693 | 36 | { |
e8bf8df9 | 37 | struct clk_lookup *p, *cl = NULL; |
67b50871 | 38 | int match, best_found = 0, best_possible = 0; |
39 | ||
40 | if (dev_id) | |
41 | best_possible += 2; | |
42 | if (con_id) | |
43 | best_possible += 1; | |
0318e693 RK |
44 | |
45 | list_for_each_entry(p, &clocks, node) { | |
0318e693 | 46 | match = 0; |
409dc360 RK |
47 | if (p->dev_id) { |
48 | if (!dev_id || strcmp(p->dev_id, dev_id)) | |
49 | continue; | |
50 | match += 2; | |
51 | } | |
52 | if (p->con_id) { | |
53 | if (!con_id || strcmp(p->con_id, con_id)) | |
54 | continue; | |
55 | match += 1; | |
56 | } | |
0318e693 | 57 | |
67b50871 | 58 | if (match > best_found) { |
e8bf8df9 | 59 | cl = p; |
67b50871 | 60 | if (match != best_possible) |
61 | best_found = match; | |
e4bf5bec | 62 | else |
63 | break; | |
0318e693 RK |
64 | } |
65 | } | |
e8bf8df9 | 66 | return cl; |
0318e693 RK |
67 | } |
68 | ||
05fd8e73 | 69 | struct clk *clk_get_sys(const char *dev_id, const char *con_id) |
0318e693 | 70 | { |
e8bf8df9 | 71 | struct clk_lookup *cl; |
0318e693 RK |
72 | |
73 | mutex_lock(&clocks_mutex); | |
e8bf8df9 RK |
74 | cl = clk_find(dev_id, con_id); |
75 | if (cl && !__clk_get(cl->clk)) | |
76 | cl = NULL; | |
0318e693 RK |
77 | mutex_unlock(&clocks_mutex); |
78 | ||
e8bf8df9 | 79 | return cl ? cl->clk : ERR_PTR(-ENOENT); |
0318e693 | 80 | } |
05fd8e73 SH |
81 | EXPORT_SYMBOL(clk_get_sys); |
82 | ||
83 | struct clk *clk_get(struct device *dev, const char *con_id) | |
84 | { | |
85 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
86 | ||
87 | return clk_get_sys(dev_id, con_id); | |
88 | } | |
0318e693 RK |
89 | EXPORT_SYMBOL(clk_get); |
90 | ||
91 | void clk_put(struct clk *clk) | |
92 | { | |
93 | __clk_put(clk); | |
94 | } | |
95 | EXPORT_SYMBOL(clk_put); | |
96 | ||
a8a97db9 MB |
97 | static void devm_clk_release(struct device *dev, void *res) |
98 | { | |
99 | clk_put(*(struct clk **)res); | |
100 | } | |
101 | ||
102 | struct clk *devm_clk_get(struct device *dev, const char *id) | |
103 | { | |
104 | struct clk **ptr, *clk; | |
105 | ||
106 | ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL); | |
107 | if (!ptr) | |
108 | return ERR_PTR(-ENOMEM); | |
109 | ||
110 | clk = clk_get(dev, id); | |
111 | if (!IS_ERR(clk)) { | |
112 | *ptr = clk; | |
113 | devres_add(dev, ptr); | |
114 | } else { | |
115 | devres_free(ptr); | |
116 | } | |
117 | ||
118 | return clk; | |
119 | } | |
120 | EXPORT_SYMBOL(devm_clk_get); | |
121 | ||
122 | static int devm_clk_match(struct device *dev, void *res, void *data) | |
123 | { | |
124 | struct clk **c = res; | |
125 | if (!c || !*c) { | |
126 | WARN_ON(!c || !*c); | |
127 | return 0; | |
128 | } | |
129 | return *c == data; | |
130 | } | |
131 | ||
132 | void devm_clk_put(struct device *dev, struct clk *clk) | |
133 | { | |
134 | int ret; | |
135 | ||
136 | ret = devres_destroy(dev, devm_clk_release, devm_clk_match, clk); | |
137 | ||
138 | WARN_ON(ret); | |
139 | } | |
140 | EXPORT_SYMBOL(devm_clk_put); | |
141 | ||
0318e693 RK |
142 | void clkdev_add(struct clk_lookup *cl) |
143 | { | |
144 | mutex_lock(&clocks_mutex); | |
145 | list_add_tail(&cl->node, &clocks); | |
146 | mutex_unlock(&clocks_mutex); | |
147 | } | |
148 | EXPORT_SYMBOL(clkdev_add); | |
149 | ||
0a0300dc RK |
150 | void __init clkdev_add_table(struct clk_lookup *cl, size_t num) |
151 | { | |
152 | mutex_lock(&clocks_mutex); | |
153 | while (num--) { | |
154 | list_add_tail(&cl->node, &clocks); | |
155 | cl++; | |
156 | } | |
157 | mutex_unlock(&clocks_mutex); | |
158 | } | |
159 | ||
0318e693 RK |
160 | #define MAX_DEV_ID 20 |
161 | #define MAX_CON_ID 16 | |
162 | ||
163 | struct clk_lookup_alloc { | |
164 | struct clk_lookup cl; | |
165 | char dev_id[MAX_DEV_ID]; | |
166 | char con_id[MAX_CON_ID]; | |
167 | }; | |
168 | ||
e9d7f406 RK |
169 | static struct clk_lookup * __init_refok |
170 | vclkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, | |
171 | va_list ap) | |
0318e693 RK |
172 | { |
173 | struct clk_lookup_alloc *cla; | |
174 | ||
6d803ba7 | 175 | cla = __clkdev_alloc(sizeof(*cla)); |
0318e693 RK |
176 | if (!cla) |
177 | return NULL; | |
178 | ||
179 | cla->cl.clk = clk; | |
180 | if (con_id) { | |
181 | strlcpy(cla->con_id, con_id, sizeof(cla->con_id)); | |
182 | cla->cl.con_id = cla->con_id; | |
183 | } | |
184 | ||
185 | if (dev_fmt) { | |
0318e693 RK |
186 | vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); |
187 | cla->cl.dev_id = cla->dev_id; | |
0318e693 RK |
188 | } |
189 | ||
190 | return &cla->cl; | |
191 | } | |
e9d7f406 RK |
192 | |
193 | struct clk_lookup * __init_refok | |
194 | clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...) | |
195 | { | |
196 | struct clk_lookup *cl; | |
197 | va_list ap; | |
198 | ||
199 | va_start(ap, dev_fmt); | |
200 | cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); | |
201 | va_end(ap); | |
202 | ||
203 | return cl; | |
204 | } | |
0318e693 RK |
205 | EXPORT_SYMBOL(clkdev_alloc); |
206 | ||
c0683039 TL |
207 | int clk_add_alias(const char *alias, const char *alias_dev_name, char *id, |
208 | struct device *dev) | |
209 | { | |
210 | struct clk *r = clk_get(dev, id); | |
211 | struct clk_lookup *l; | |
212 | ||
213 | if (IS_ERR(r)) | |
214 | return PTR_ERR(r); | |
215 | ||
216 | l = clkdev_alloc(r, alias, alias_dev_name); | |
217 | clk_put(r); | |
218 | if (!l) | |
219 | return -ENODEV; | |
220 | clkdev_add(l); | |
221 | return 0; | |
222 | } | |
223 | EXPORT_SYMBOL(clk_add_alias); | |
224 | ||
0318e693 RK |
225 | /* |
226 | * clkdev_drop - remove a clock dynamically allocated | |
227 | */ | |
228 | void clkdev_drop(struct clk_lookup *cl) | |
229 | { | |
230 | mutex_lock(&clocks_mutex); | |
231 | list_del(&cl->node); | |
232 | mutex_unlock(&clocks_mutex); | |
233 | kfree(cl); | |
234 | } | |
235 | EXPORT_SYMBOL(clkdev_drop); | |
e9d7f406 RK |
236 | |
237 | /** | |
238 | * clk_register_clkdev - register one clock lookup for a struct clk | |
239 | * @clk: struct clk to associate with all clk_lookups | |
240 | * @con_id: connection ID string on device | |
241 | * @dev_id: format string describing device name | |
242 | * | |
243 | * con_id or dev_id may be NULL as a wildcard, just as in the rest of | |
244 | * clkdev. | |
245 | * | |
246 | * To make things easier for mass registration, we detect error clks | |
247 | * from a previous clk_register() call, and return the error code for | |
248 | * those. This is to permit this function to be called immediately | |
249 | * after clk_register(). | |
250 | */ | |
251 | int clk_register_clkdev(struct clk *clk, const char *con_id, | |
252 | const char *dev_fmt, ...) | |
253 | { | |
254 | struct clk_lookup *cl; | |
255 | va_list ap; | |
256 | ||
257 | if (IS_ERR(clk)) | |
258 | return PTR_ERR(clk); | |
259 | ||
260 | va_start(ap, dev_fmt); | |
261 | cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); | |
262 | va_end(ap); | |
263 | ||
264 | if (!cl) | |
265 | return -ENOMEM; | |
266 | ||
267 | clkdev_add(cl); | |
268 | ||
269 | return 0; | |
270 | } | |
271 | ||
272 | /** | |
273 | * clk_register_clkdevs - register a set of clk_lookup for a struct clk | |
274 | * @clk: struct clk to associate with all clk_lookups | |
275 | * @cl: array of clk_lookup structures with con_id and dev_id pre-initialized | |
276 | * @num: number of clk_lookup structures to register | |
277 | * | |
278 | * To make things easier for mass registration, we detect error clks | |
279 | * from a previous clk_register() call, and return the error code for | |
280 | * those. This is to permit this function to be called immediately | |
281 | * after clk_register(). | |
282 | */ | |
283 | int clk_register_clkdevs(struct clk *clk, struct clk_lookup *cl, size_t num) | |
284 | { | |
285 | unsigned i; | |
286 | ||
287 | if (IS_ERR(clk)) | |
288 | return PTR_ERR(clk); | |
289 | ||
290 | for (i = 0; i < num; i++, cl++) { | |
291 | cl->clk = clk; | |
292 | clkdev_add(cl); | |
293 | } | |
294 | ||
295 | return 0; | |
296 | } | |
297 | EXPORT_SYMBOL(clk_register_clkdevs); |