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> |
035a61c3 | 22 | #include <linux/clk-provider.h> |
766e6a4e | 23 | #include <linux/of.h> |
0318e693 | 24 | |
3a3d2b05 SN |
25 | #include "clk.h" |
26 | ||
0318e693 RK |
27 | static LIST_HEAD(clocks); |
28 | static DEFINE_MUTEX(clocks_mutex); | |
29 | ||
137f8a72 | 30 | #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) |
73e0e496 SB |
31 | static struct clk *__of_clk_get(struct device_node *np, int index, |
32 | const char *dev_id, const char *con_id) | |
766e6a4e GL |
33 | { |
34 | struct of_phandle_args clkspec; | |
35 | struct clk *clk; | |
36 | int rc; | |
37 | ||
38 | if (index < 0) | |
39 | return ERR_PTR(-EINVAL); | |
40 | ||
41 | rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index, | |
42 | &clkspec); | |
43 | if (rc) | |
44 | return ERR_PTR(rc); | |
45 | ||
306c342f | 46 | clk = __of_clk_get_from_provider(&clkspec, dev_id, con_id); |
766e6a4e | 47 | of_node_put(clkspec.np); |
035a61c3 TV |
48 | |
49 | return clk; | |
50 | } | |
51 | ||
52 | struct clk *of_clk_get(struct device_node *np, int index) | |
53 | { | |
73e0e496 | 54 | return __of_clk_get(np, index, np->full_name, NULL); |
766e6a4e GL |
55 | } |
56 | EXPORT_SYMBOL(of_clk_get); | |
57 | ||
035a61c3 TV |
58 | static struct clk *__of_clk_get_by_name(struct device_node *np, |
59 | const char *dev_id, | |
60 | const char *name) | |
766e6a4e GL |
61 | { |
62 | struct clk *clk = ERR_PTR(-ENOENT); | |
63 | ||
64 | /* Walk up the tree of devices looking for a clock that matches */ | |
65 | while (np) { | |
66 | int index = 0; | |
67 | ||
68 | /* | |
69 | * For named clocks, first look up the name in the | |
70 | * "clock-names" property. If it cannot be found, then | |
71 | * index will be an error code, and of_clk_get() will fail. | |
72 | */ | |
73 | if (name) | |
74 | index = of_property_match_string(np, "clock-names", name); | |
73e0e496 | 75 | clk = __of_clk_get(np, index, dev_id, name); |
035a61c3 | 76 | if (!IS_ERR(clk)) { |
766e6a4e | 77 | break; |
73e0e496 | 78 | } else if (name && index >= 0) { |
d8e53c3d SB |
79 | if (PTR_ERR(clk) != -EPROBE_DEFER) |
80 | pr_err("ERROR: could not get clock %s:%s(%i)\n", | |
81 | np->full_name, name ? name : "", index); | |
766e6a4e GL |
82 | return clk; |
83 | } | |
84 | ||
85 | /* | |
86 | * No matching clock found on this node. If the parent node | |
87 | * has a "clock-ranges" property, then we can try one of its | |
88 | * clocks. | |
89 | */ | |
90 | np = np->parent; | |
91 | if (np && !of_get_property(np, "clock-ranges", NULL)) | |
92 | break; | |
93 | } | |
94 | ||
95 | return clk; | |
96 | } | |
035a61c3 TV |
97 | |
98 | /** | |
99 | * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node | |
100 | * @np: pointer to clock consumer node | |
101 | * @name: name of consumer's clock input, or NULL for the first clock reference | |
102 | * | |
103 | * This function parses the clocks and clock-names properties, | |
104 | * and uses them to look up the struct clk from the registered list of clock | |
105 | * providers. | |
106 | */ | |
107 | struct clk *of_clk_get_by_name(struct device_node *np, const char *name) | |
108 | { | |
109 | if (!np) | |
110 | return ERR_PTR(-ENOENT); | |
111 | ||
112 | return __of_clk_get_by_name(np, np->full_name, name); | |
113 | } | |
766e6a4e | 114 | EXPORT_SYMBOL(of_clk_get_by_name); |
035a61c3 TV |
115 | |
116 | #else /* defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) */ | |
117 | ||
118 | static struct clk *__of_clk_get_by_name(struct device_node *np, | |
119 | const char *dev_id, | |
120 | const char *name) | |
121 | { | |
122 | return ERR_PTR(-ENOENT); | |
123 | } | |
766e6a4e GL |
124 | #endif |
125 | ||
409dc360 RK |
126 | /* |
127 | * Find the correct struct clk for the device and connection ID. | |
128 | * We do slightly fuzzy matching here: | |
129 | * An entry with a NULL ID is assumed to be a wildcard. | |
130 | * If an entry has a device ID, it must match | |
131 | * If an entry has a connection ID, it must match | |
132 | * Then we take the most specific entry - with the following | |
659431fc | 133 | * order of precedence: dev+con > dev only > con only. |
409dc360 | 134 | */ |
e8bf8df9 | 135 | static struct clk_lookup *clk_find(const char *dev_id, const char *con_id) |
0318e693 | 136 | { |
e8bf8df9 | 137 | struct clk_lookup *p, *cl = NULL; |
67b50871 | 138 | int match, best_found = 0, best_possible = 0; |
139 | ||
140 | if (dev_id) | |
141 | best_possible += 2; | |
142 | if (con_id) | |
143 | best_possible += 1; | |
0318e693 RK |
144 | |
145 | list_for_each_entry(p, &clocks, node) { | |
0318e693 | 146 | match = 0; |
409dc360 RK |
147 | if (p->dev_id) { |
148 | if (!dev_id || strcmp(p->dev_id, dev_id)) | |
149 | continue; | |
150 | match += 2; | |
151 | } | |
152 | if (p->con_id) { | |
153 | if (!con_id || strcmp(p->con_id, con_id)) | |
154 | continue; | |
155 | match += 1; | |
156 | } | |
0318e693 | 157 | |
67b50871 | 158 | if (match > best_found) { |
e8bf8df9 | 159 | cl = p; |
67b50871 | 160 | if (match != best_possible) |
161 | best_found = match; | |
e4bf5bec | 162 | else |
163 | break; | |
0318e693 RK |
164 | } |
165 | } | |
e8bf8df9 | 166 | return cl; |
0318e693 RK |
167 | } |
168 | ||
05fd8e73 | 169 | struct clk *clk_get_sys(const char *dev_id, const char *con_id) |
0318e693 | 170 | { |
e8bf8df9 | 171 | struct clk_lookup *cl; |
035a61c3 | 172 | struct clk *clk = NULL; |
0318e693 RK |
173 | |
174 | mutex_lock(&clocks_mutex); | |
035a61c3 | 175 | |
e8bf8df9 | 176 | cl = clk_find(dev_id, con_id); |
035a61c3 TV |
177 | if (!cl) |
178 | goto out; | |
179 | ||
73e0e496 SB |
180 | clk = __clk_create_clk(__clk_get_hw(cl->clk), dev_id, con_id); |
181 | if (IS_ERR(clk)) | |
182 | goto out; | |
183 | ||
184 | if (!__clk_get(clk)) { | |
185 | __clk_free_clk(clk); | |
e8bf8df9 | 186 | cl = NULL; |
035a61c3 TV |
187 | goto out; |
188 | } | |
189 | ||
035a61c3 | 190 | out: |
0318e693 RK |
191 | mutex_unlock(&clocks_mutex); |
192 | ||
035a61c3 | 193 | return cl ? clk : ERR_PTR(-ENOENT); |
0318e693 | 194 | } |
05fd8e73 SH |
195 | EXPORT_SYMBOL(clk_get_sys); |
196 | ||
197 | struct clk *clk_get(struct device *dev, const char *con_id) | |
198 | { | |
199 | const char *dev_id = dev ? dev_name(dev) : NULL; | |
766e6a4e GL |
200 | struct clk *clk; |
201 | ||
202 | if (dev) { | |
035a61c3 TV |
203 | clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id); |
204 | if (!IS_ERR(clk) || PTR_ERR(clk) == -EPROBE_DEFER) | |
a34cd466 | 205 | return clk; |
766e6a4e | 206 | } |
05fd8e73 SH |
207 | |
208 | return clk_get_sys(dev_id, con_id); | |
209 | } | |
0318e693 RK |
210 | EXPORT_SYMBOL(clk_get); |
211 | ||
212 | void clk_put(struct clk *clk) | |
213 | { | |
214 | __clk_put(clk); | |
215 | } | |
216 | EXPORT_SYMBOL(clk_put); | |
217 | ||
218 | void clkdev_add(struct clk_lookup *cl) | |
219 | { | |
220 | mutex_lock(&clocks_mutex); | |
221 | list_add_tail(&cl->node, &clocks); | |
222 | mutex_unlock(&clocks_mutex); | |
223 | } | |
224 | EXPORT_SYMBOL(clkdev_add); | |
225 | ||
0a0300dc RK |
226 | void __init clkdev_add_table(struct clk_lookup *cl, size_t num) |
227 | { | |
228 | mutex_lock(&clocks_mutex); | |
229 | while (num--) { | |
230 | list_add_tail(&cl->node, &clocks); | |
231 | cl++; | |
232 | } | |
233 | mutex_unlock(&clocks_mutex); | |
234 | } | |
235 | ||
0318e693 RK |
236 | #define MAX_DEV_ID 20 |
237 | #define MAX_CON_ID 16 | |
238 | ||
239 | struct clk_lookup_alloc { | |
240 | struct clk_lookup cl; | |
241 | char dev_id[MAX_DEV_ID]; | |
242 | char con_id[MAX_CON_ID]; | |
243 | }; | |
244 | ||
e9d7f406 RK |
245 | static struct clk_lookup * __init_refok |
246 | vclkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, | |
247 | va_list ap) | |
0318e693 RK |
248 | { |
249 | struct clk_lookup_alloc *cla; | |
250 | ||
6d803ba7 | 251 | cla = __clkdev_alloc(sizeof(*cla)); |
0318e693 RK |
252 | if (!cla) |
253 | return NULL; | |
254 | ||
255 | cla->cl.clk = clk; | |
256 | if (con_id) { | |
257 | strlcpy(cla->con_id, con_id, sizeof(cla->con_id)); | |
258 | cla->cl.con_id = cla->con_id; | |
259 | } | |
260 | ||
261 | if (dev_fmt) { | |
0318e693 RK |
262 | vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); |
263 | cla->cl.dev_id = cla->dev_id; | |
0318e693 RK |
264 | } |
265 | ||
266 | return &cla->cl; | |
267 | } | |
e9d7f406 RK |
268 | |
269 | struct clk_lookup * __init_refok | |
270 | clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...) | |
271 | { | |
272 | struct clk_lookup *cl; | |
273 | va_list ap; | |
274 | ||
275 | va_start(ap, dev_fmt); | |
276 | cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); | |
277 | va_end(ap); | |
278 | ||
279 | return cl; | |
280 | } | |
0318e693 RK |
281 | EXPORT_SYMBOL(clkdev_alloc); |
282 | ||
c0683039 TL |
283 | int clk_add_alias(const char *alias, const char *alias_dev_name, char *id, |
284 | struct device *dev) | |
285 | { | |
286 | struct clk *r = clk_get(dev, id); | |
287 | struct clk_lookup *l; | |
288 | ||
289 | if (IS_ERR(r)) | |
290 | return PTR_ERR(r); | |
291 | ||
292 | l = clkdev_alloc(r, alias, alias_dev_name); | |
293 | clk_put(r); | |
294 | if (!l) | |
295 | return -ENODEV; | |
296 | clkdev_add(l); | |
297 | return 0; | |
298 | } | |
299 | EXPORT_SYMBOL(clk_add_alias); | |
300 | ||
0318e693 RK |
301 | /* |
302 | * clkdev_drop - remove a clock dynamically allocated | |
303 | */ | |
304 | void clkdev_drop(struct clk_lookup *cl) | |
305 | { | |
306 | mutex_lock(&clocks_mutex); | |
307 | list_del(&cl->node); | |
308 | mutex_unlock(&clocks_mutex); | |
309 | kfree(cl); | |
310 | } | |
311 | EXPORT_SYMBOL(clkdev_drop); | |
e9d7f406 RK |
312 | |
313 | /** | |
314 | * clk_register_clkdev - register one clock lookup for a struct clk | |
315 | * @clk: struct clk to associate with all clk_lookups | |
316 | * @con_id: connection ID string on device | |
317 | * @dev_id: format string describing device name | |
318 | * | |
319 | * con_id or dev_id may be NULL as a wildcard, just as in the rest of | |
320 | * clkdev. | |
321 | * | |
322 | * To make things easier for mass registration, we detect error clks | |
323 | * from a previous clk_register() call, and return the error code for | |
324 | * those. This is to permit this function to be called immediately | |
325 | * after clk_register(). | |
326 | */ | |
327 | int clk_register_clkdev(struct clk *clk, const char *con_id, | |
328 | const char *dev_fmt, ...) | |
329 | { | |
330 | struct clk_lookup *cl; | |
331 | va_list ap; | |
332 | ||
333 | if (IS_ERR(clk)) | |
334 | return PTR_ERR(clk); | |
335 | ||
336 | va_start(ap, dev_fmt); | |
337 | cl = vclkdev_alloc(clk, con_id, dev_fmt, ap); | |
338 | va_end(ap); | |
339 | ||
340 | if (!cl) | |
341 | return -ENOMEM; | |
342 | ||
343 | clkdev_add(cl); | |
344 | ||
345 | return 0; | |
346 | } | |
a251361a | 347 | EXPORT_SYMBOL(clk_register_clkdev); |
e9d7f406 RK |
348 | |
349 | /** | |
350 | * clk_register_clkdevs - register a set of clk_lookup for a struct clk | |
351 | * @clk: struct clk to associate with all clk_lookups | |
352 | * @cl: array of clk_lookup structures with con_id and dev_id pre-initialized | |
353 | * @num: number of clk_lookup structures to register | |
354 | * | |
355 | * To make things easier for mass registration, we detect error clks | |
356 | * from a previous clk_register() call, and return the error code for | |
357 | * those. This is to permit this function to be called immediately | |
358 | * after clk_register(). | |
359 | */ | |
360 | int clk_register_clkdevs(struct clk *clk, struct clk_lookup *cl, size_t num) | |
361 | { | |
362 | unsigned i; | |
363 | ||
364 | if (IS_ERR(clk)) | |
365 | return PTR_ERR(clk); | |
366 | ||
367 | for (i = 0; i < num; i++, cl++) { | |
368 | cl->clk = clk; | |
369 | clkdev_add(cl); | |
370 | } | |
371 | ||
372 | return 0; | |
373 | } | |
374 | EXPORT_SYMBOL(clk_register_clkdevs); |