Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 1 | /* |
Jean-Christop PLAGNIOL-VILLARD | 6d803ba | 2010-11-17 10:04:33 +0100 | [diff] [blame] | 2 | * drivers/clk/clkdev.c |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 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> |
Hartley Sweeten | c0c60c4 | 2009-08-04 23:38:06 +0100 | [diff] [blame] | 20 | #include <linux/clk.h> |
Jean-Christop PLAGNIOL-VILLARD | 6d803ba | 2010-11-17 10:04:33 +0100 | [diff] [blame] | 21 | #include <linux/clkdev.h> |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 22 | |
| 23 | static LIST_HEAD(clocks); |
| 24 | static DEFINE_MUTEX(clocks_mutex); |
| 25 | |
Russell King | 409dc36 | 2009-01-24 10:14:37 +0000 | [diff] [blame] | 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 |
Uwe Kleine-König | 659431f | 2010-01-18 16:02:48 +0100 | [diff] [blame] | 33 | * order of precedence: dev+con > dev only > con only. |
Russell King | 409dc36 | 2009-01-24 10:14:37 +0000 | [diff] [blame] | 34 | */ |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 35 | static struct clk_lookup *clk_find(const char *dev_id, const char *con_id) |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 36 | { |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 37 | struct clk_lookup *p, *cl = NULL; |
viresh kumar | 67b5087 | 2012-04-19 04:23:25 +0100 | [diff] [blame] | 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; |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 44 | |
| 45 | list_for_each_entry(p, &clocks, node) { |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 46 | match = 0; |
Russell King | 409dc36 | 2009-01-24 10:14:37 +0000 | [diff] [blame] | 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 | } |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 57 | |
viresh kumar | 67b5087 | 2012-04-19 04:23:25 +0100 | [diff] [blame] | 58 | if (match > best_found) { |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 59 | cl = p; |
viresh kumar | 67b5087 | 2012-04-19 04:23:25 +0100 | [diff] [blame] | 60 | if (match != best_possible) |
| 61 | best_found = match; |
viresh kumar | e4bf5be | 2010-03-09 11:54:30 +0100 | [diff] [blame] | 62 | else |
| 63 | break; |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 64 | } |
| 65 | } |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 66 | return cl; |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 67 | } |
| 68 | |
Sascha Hauer | 05fd8e7 | 2009-03-07 12:55:49 +0100 | [diff] [blame] | 69 | struct clk *clk_get_sys(const char *dev_id, const char *con_id) |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 70 | { |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 71 | struct clk_lookup *cl; |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 72 | |
| 73 | mutex_lock(&clocks_mutex); |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 74 | cl = clk_find(dev_id, con_id); |
| 75 | if (cl && !__clk_get(cl->clk)) |
| 76 | cl = NULL; |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 77 | mutex_unlock(&clocks_mutex); |
| 78 | |
Russell King | e8bf8df | 2011-04-30 10:14:08 +0100 | [diff] [blame] | 79 | return cl ? cl->clk : ERR_PTR(-ENOENT); |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 80 | } |
Sascha Hauer | 05fd8e7 | 2009-03-07 12:55:49 +0100 | [diff] [blame] | 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 | } |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 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 | |
Mark Brown | a8a97db | 2012-04-05 11:42:09 +0100 | [diff] [blame] | 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 | |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 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 | |
Russell King | 0a0300d | 2010-01-12 12:28:00 +0000 | [diff] [blame] | 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 | |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 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 | |
Russell King | e9d7f40 | 2012-05-02 09:30:32 +0100 | [diff] [blame] | 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) |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 172 | { |
| 173 | struct clk_lookup_alloc *cla; |
| 174 | |
Jean-Christop PLAGNIOL-VILLARD | 6d803ba | 2010-11-17 10:04:33 +0100 | [diff] [blame] | 175 | cla = __clkdev_alloc(sizeof(*cla)); |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 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) { |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 186 | vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap); |
| 187 | cla->cl.dev_id = cla->dev_id; |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 188 | } |
| 189 | |
| 190 | return &cla->cl; |
| 191 | } |
Russell King | e9d7f40 | 2012-05-02 09:30:32 +0100 | [diff] [blame] | 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 | } |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 205 | EXPORT_SYMBOL(clkdev_alloc); |
| 206 | |
Tony Lindgren | c068303 | 2009-06-03 17:43:14 +0100 | [diff] [blame] | 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 | |
Russell King | 0318e69 | 2008-11-09 16:32:46 +0000 | [diff] [blame] | 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); |
Russell King | e9d7f40 | 2012-05-02 09:30:32 +0100 | [diff] [blame] | 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); |