Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 1 | /* |
| 2 | * linux/drivers/thermal/cpu_cooling.c |
| 3 | * |
| 4 | * Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) |
| 5 | * Copyright (C) 2012 Amit Daniel <amit.kachhap@linaro.org> |
| 6 | * |
| 7 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License as published by |
| 10 | * the Free Software Foundation; version 2 of the License. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, but |
| 13 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License along |
| 18 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 19 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. |
| 20 | * |
| 21 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| 22 | */ |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 23 | #include <linux/module.h> |
| 24 | #include <linux/thermal.h> |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 25 | #include <linux/cpufreq.h> |
| 26 | #include <linux/err.h> |
| 27 | #include <linux/slab.h> |
| 28 | #include <linux/cpu.h> |
| 29 | #include <linux/cpu_cooling.h> |
| 30 | |
| 31 | /** |
Eduardo Valentin | 3b3c074 | 2013-04-17 17:11:56 +0000 | [diff] [blame] | 32 | * struct cpufreq_cooling_device - data for cooling device with cpufreq |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 33 | * @id: unique integer value corresponding to each cpufreq_cooling_device |
| 34 | * registered. |
Eduardo Valentin | 3b3c074 | 2013-04-17 17:11:56 +0000 | [diff] [blame] | 35 | * @cool_dev: thermal_cooling_device pointer to keep track of the |
| 36 | * registered cooling device. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 37 | * @cpufreq_state: integer value representing the current state of cpufreq |
| 38 | * cooling devices. |
| 39 | * @cpufreq_val: integer value representing the absolute value of the clipped |
| 40 | * frequency. |
| 41 | * @allowed_cpus: all the cpus involved for this cpufreq_cooling_device. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 42 | * |
| 43 | * This structure is required for keeping information of each |
Eduardo Valentin | 67d0b2a | 2013-04-17 17:12:19 +0000 | [diff] [blame] | 44 | * cpufreq_cooling_device registered. In order to prevent corruption of this a |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 45 | * mutex lock cooling_cpufreq_lock is used. |
| 46 | */ |
| 47 | struct cpufreq_cooling_device { |
| 48 | int id; |
| 49 | struct thermal_cooling_device *cool_dev; |
| 50 | unsigned int cpufreq_state; |
| 51 | unsigned int cpufreq_val; |
| 52 | struct cpumask allowed_cpus; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 53 | }; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 54 | static DEFINE_IDR(cpufreq_idr); |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 55 | static DEFINE_MUTEX(cooling_cpufreq_lock); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 56 | |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 57 | static unsigned int cpufreq_dev_count; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 58 | |
| 59 | /* notify_table passes value to the CPUFREQ_ADJUST callback function. */ |
| 60 | #define NOTIFY_INVALID NULL |
Sachin Kamat | a0f846c | 2012-11-15 12:19:44 +0530 | [diff] [blame] | 61 | static struct cpufreq_cooling_device *notify_device; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 62 | |
| 63 | /** |
| 64 | * get_idr - function to get a unique id. |
| 65 | * @idr: struct idr * handle used to create a id. |
| 66 | * @id: int * value generated by this function. |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 67 | * |
| 68 | * This function will populate @id with an unique |
| 69 | * id, using the idr API. |
| 70 | * |
| 71 | * Return: 0 on success, an error code on failure. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 72 | */ |
| 73 | static int get_idr(struct idr *idr, int *id) |
| 74 | { |
Tejun Heo | 6deb69f | 2013-02-27 17:04:46 -0800 | [diff] [blame] | 75 | int ret; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 76 | |
| 77 | mutex_lock(&cooling_cpufreq_lock); |
Tejun Heo | 6deb69f | 2013-02-27 17:04:46 -0800 | [diff] [blame] | 78 | ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 79 | mutex_unlock(&cooling_cpufreq_lock); |
Tejun Heo | 6deb69f | 2013-02-27 17:04:46 -0800 | [diff] [blame] | 80 | if (unlikely(ret < 0)) |
| 81 | return ret; |
| 82 | *id = ret; |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 83 | |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 84 | return 0; |
| 85 | } |
| 86 | |
| 87 | /** |
| 88 | * release_idr - function to free the unique id. |
| 89 | * @idr: struct idr * handle used for creating the id. |
| 90 | * @id: int value representing the unique id. |
| 91 | */ |
| 92 | static void release_idr(struct idr *idr, int id) |
| 93 | { |
| 94 | mutex_lock(&cooling_cpufreq_lock); |
| 95 | idr_remove(idr, id); |
| 96 | mutex_unlock(&cooling_cpufreq_lock); |
| 97 | } |
| 98 | |
| 99 | /* Below code defines functions to be used for cpufreq as cooling device */ |
| 100 | |
| 101 | /** |
Eduardo Valentin | 82b9ee4 | 2013-04-17 17:12:00 +0000 | [diff] [blame] | 102 | * is_cpufreq_valid - function to check frequency transitioning capability. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 103 | * @cpu: cpu for which check is needed. |
Eduardo Valentin | 82b9ee4 | 2013-04-17 17:12:00 +0000 | [diff] [blame] | 104 | * |
| 105 | * This function will check the current state of the system if |
| 106 | * it is capable of changing the frequency for a given @cpu. |
| 107 | * |
| 108 | * Return: 0 if the system is not currently capable of changing |
| 109 | * the frequency of given cpu. !0 in case the frequency is changeable. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 110 | */ |
| 111 | static int is_cpufreq_valid(int cpu) |
| 112 | { |
| 113 | struct cpufreq_policy policy; |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 114 | |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 115 | return !cpufreq_get_policy(&policy, cpu); |
| 116 | } |
| 117 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 118 | enum cpufreq_cooling_property { |
| 119 | GET_LEVEL, |
| 120 | GET_FREQ, |
| 121 | GET_MAXL, |
| 122 | }; |
| 123 | |
Eduardo Valentin | 2d6f28f | 2013-04-17 17:12:01 +0000 | [diff] [blame] | 124 | /** |
| 125 | * get_property - fetch a property of interest for a give cpu. |
| 126 | * @cpu: cpu for which the property is required |
| 127 | * @input: query parameter |
| 128 | * @output: query return |
| 129 | * @property: type of query (frequency, level, max level) |
| 130 | * |
| 131 | * This is the common function to |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 132 | * 1. get maximum cpu cooling states |
| 133 | * 2. translate frequency to cooling state |
| 134 | * 3. translate cooling state to frequency |
| 135 | * Note that the code may be not in good shape |
| 136 | * but it is written in this way in order to: |
| 137 | * a) reduce duplicate code as most of the code can be shared. |
| 138 | * b) make sure the logic is consistent when translating between |
| 139 | * cooling states and frequencies. |
Eduardo Valentin | 2d6f28f | 2013-04-17 17:12:01 +0000 | [diff] [blame] | 140 | * |
| 141 | * Return: 0 on success, -EINVAL when invalid parameters are passed. |
| 142 | */ |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 143 | static int get_property(unsigned int cpu, unsigned long input, |
Eduardo Valentin | d8892a0 | 2013-04-17 17:12:03 +0000 | [diff] [blame] | 144 | unsigned int *output, |
| 145 | enum cpufreq_cooling_property property) |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 146 | { |
| 147 | int i, j; |
Eduardo Valentin | 4469b99 | 2013-04-17 17:11:58 +0000 | [diff] [blame] | 148 | unsigned long max_level = 0, level = 0; |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 149 | unsigned int freq = CPUFREQ_ENTRY_INVALID; |
| 150 | int descend = -1; |
| 151 | struct cpufreq_frequency_table *table = |
| 152 | cpufreq_frequency_get_table(cpu); |
Eduardo Valentin | 79d2640 | 2013-04-17 17:11:55 +0000 | [diff] [blame] | 153 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 154 | if (!output) |
| 155 | return -EINVAL; |
| 156 | |
| 157 | if (!table) |
| 158 | return -EINVAL; |
| 159 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 160 | for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { |
| 161 | /* ignore invalid entries */ |
| 162 | if (table[i].frequency == CPUFREQ_ENTRY_INVALID) |
| 163 | continue; |
| 164 | |
| 165 | /* ignore duplicate entry */ |
| 166 | if (freq == table[i].frequency) |
| 167 | continue; |
| 168 | |
| 169 | /* get the frequency order */ |
Shawn Guo | 24c7a38 | 2013-05-28 06:22:32 +0000 | [diff] [blame] | 170 | if (freq != CPUFREQ_ENTRY_INVALID && descend == -1) |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 171 | descend = !!(freq > table[i].frequency); |
| 172 | |
| 173 | freq = table[i].frequency; |
| 174 | max_level++; |
| 175 | } |
| 176 | |
| 177 | /* get max level */ |
| 178 | if (property == GET_MAXL) { |
| 179 | *output = (unsigned int)max_level; |
| 180 | return 0; |
| 181 | } |
| 182 | |
| 183 | if (property == GET_FREQ) |
Eduardo Valentin | ef5e212 | 2013-04-17 17:12:06 +0000 | [diff] [blame] | 184 | level = descend ? input : (max_level - input - 1); |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 185 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 186 | for (i = 0, j = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { |
| 187 | /* ignore invalid entry */ |
| 188 | if (table[i].frequency == CPUFREQ_ENTRY_INVALID) |
| 189 | continue; |
| 190 | |
| 191 | /* ignore duplicate entry */ |
| 192 | if (freq == table[i].frequency) |
| 193 | continue; |
| 194 | |
| 195 | /* now we have a valid frequency entry */ |
| 196 | freq = table[i].frequency; |
| 197 | |
| 198 | if (property == GET_LEVEL && (unsigned int)input == freq) { |
| 199 | /* get level by frequency */ |
| 200 | *output = descend ? j : (max_level - j - 1); |
| 201 | return 0; |
| 202 | } |
| 203 | if (property == GET_FREQ && level == j) { |
| 204 | /* get frequency by level */ |
| 205 | *output = freq; |
| 206 | return 0; |
| 207 | } |
| 208 | j++; |
| 209 | } |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 210 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 211 | return -EINVAL; |
| 212 | } |
| 213 | |
Eduardo Valentin | 44952d3 | 2013-04-17 17:12:05 +0000 | [diff] [blame] | 214 | /** |
| 215 | * cpufreq_cooling_get_level - for a give cpu, return the cooling level. |
| 216 | * @cpu: cpu for which the level is required |
| 217 | * @freq: the frequency of interest |
| 218 | * |
| 219 | * This function will match the cooling level corresponding to the |
| 220 | * requested @freq and return it. |
| 221 | * |
| 222 | * Return: The matched cooling level on success or THERMAL_CSTATE_INVALID |
| 223 | * otherwise. |
| 224 | */ |
Zhang Rui | 57df810 | 2013-02-08 14:52:06 +0800 | [diff] [blame] | 225 | unsigned long cpufreq_cooling_get_level(unsigned int cpu, unsigned int freq) |
| 226 | { |
| 227 | unsigned int val; |
| 228 | |
| 229 | if (get_property(cpu, (unsigned long)freq, &val, GET_LEVEL)) |
| 230 | return THERMAL_CSTATE_INVALID; |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 231 | |
Zhang Rui | 57df810 | 2013-02-08 14:52:06 +0800 | [diff] [blame] | 232 | return (unsigned long)val; |
| 233 | } |
Eduardo Valentin | 243dbd9 | 2013-04-17 17:11:57 +0000 | [diff] [blame] | 234 | EXPORT_SYMBOL_GPL(cpufreq_cooling_get_level); |
Zhang Rui | 57df810 | 2013-02-08 14:52:06 +0800 | [diff] [blame] | 235 | |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 236 | /** |
| 237 | * get_cpu_frequency - get the absolute value of frequency from level. |
| 238 | * @cpu: cpu for which frequency is fetched. |
Eduardo Valentin | 41518c4 | 2013-04-17 17:12:07 +0000 | [diff] [blame] | 239 | * @level: cooling level |
| 240 | * |
| 241 | * This function matches cooling level with frequency. Based on a cooling level |
| 242 | * of frequency, equals cooling state of cpu cooling device, it will return |
| 243 | * the corresponding frequency. |
Zhang Rui | 475f41c | 2013-02-06 09:34:32 +0800 | [diff] [blame] | 244 | * e.g level=0 --> 1st MAX FREQ, level=1 ---> 2nd MAX FREQ, .... etc |
Eduardo Valentin | 41518c4 | 2013-04-17 17:12:07 +0000 | [diff] [blame] | 245 | * |
| 246 | * Return: 0 on error, the corresponding frequency otherwise. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 247 | */ |
| 248 | static unsigned int get_cpu_frequency(unsigned int cpu, unsigned long level) |
| 249 | { |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 250 | int ret = 0; |
| 251 | unsigned int freq; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 252 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 253 | ret = get_property(cpu, level, &freq, GET_FREQ); |
| 254 | if (ret) |
| 255 | return 0; |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 256 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 257 | return freq; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 258 | } |
| 259 | |
| 260 | /** |
| 261 | * cpufreq_apply_cooling - function to apply frequency clipping. |
| 262 | * @cpufreq_device: cpufreq_cooling_device pointer containing frequency |
| 263 | * clipping data. |
| 264 | * @cooling_state: value of the cooling state. |
Eduardo Valentin | 4b33deb | 2013-04-17 17:12:08 +0000 | [diff] [blame] | 265 | * |
| 266 | * Function used to make sure the cpufreq layer is aware of current thermal |
| 267 | * limits. The limits are applied by updating the cpufreq policy. |
| 268 | * |
| 269 | * Return: 0 on success, an error code otherwise (-EINVAL in case wrong |
| 270 | * cooling state). |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 271 | */ |
| 272 | static int cpufreq_apply_cooling(struct cpufreq_cooling_device *cpufreq_device, |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 273 | unsigned long cooling_state) |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 274 | { |
| 275 | unsigned int cpuid, clip_freq; |
Laurent Navet [Mali] | bde0066 | 2013-03-12 10:47:50 +0000 | [diff] [blame] | 276 | struct cpumask *mask = &cpufreq_device->allowed_cpus; |
| 277 | unsigned int cpu = cpumask_any(mask); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 278 | |
| 279 | |
| 280 | /* Check if the old cooling action is same as new cooling action */ |
| 281 | if (cpufreq_device->cpufreq_state == cooling_state) |
| 282 | return 0; |
| 283 | |
| 284 | clip_freq = get_cpu_frequency(cpu, cooling_state); |
| 285 | if (!clip_freq) |
| 286 | return -EINVAL; |
| 287 | |
| 288 | cpufreq_device->cpufreq_state = cooling_state; |
| 289 | cpufreq_device->cpufreq_val = clip_freq; |
| 290 | notify_device = cpufreq_device; |
| 291 | |
Laurent Navet [Mali] | bde0066 | 2013-03-12 10:47:50 +0000 | [diff] [blame] | 292 | for_each_cpu(cpuid, mask) { |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 293 | if (is_cpufreq_valid(cpuid)) |
| 294 | cpufreq_update_policy(cpuid); |
| 295 | } |
| 296 | |
| 297 | notify_device = NOTIFY_INVALID; |
| 298 | |
| 299 | return 0; |
| 300 | } |
| 301 | |
| 302 | /** |
| 303 | * cpufreq_thermal_notifier - notifier callback for cpufreq policy change. |
| 304 | * @nb: struct notifier_block * with callback info. |
| 305 | * @event: value showing cpufreq event for which this function invoked. |
| 306 | * @data: callback-specific data |
Eduardo Valentin | bab3055 | 2013-04-17 17:12:09 +0000 | [diff] [blame] | 307 | * |
| 308 | * Callback to highjack the notification on cpufreq policy transition. |
| 309 | * Every time there is a change in policy, we will intercept and |
| 310 | * update the cpufreq policy with thermal constraints. |
| 311 | * |
| 312 | * Return: 0 (success) |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 313 | */ |
| 314 | static int cpufreq_thermal_notifier(struct notifier_block *nb, |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 315 | unsigned long event, void *data) |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 316 | { |
| 317 | struct cpufreq_policy *policy = data; |
| 318 | unsigned long max_freq = 0; |
| 319 | |
| 320 | if (event != CPUFREQ_ADJUST || notify_device == NOTIFY_INVALID) |
| 321 | return 0; |
| 322 | |
| 323 | if (cpumask_test_cpu(policy->cpu, ¬ify_device->allowed_cpus)) |
| 324 | max_freq = notify_device->cpufreq_val; |
| 325 | |
Eduardo Valentin | 1b9e352 | 2013-04-17 17:12:02 +0000 | [diff] [blame] | 326 | /* Never exceed user_policy.max */ |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 327 | if (max_freq > policy->user_policy.max) |
| 328 | max_freq = policy->user_policy.max; |
| 329 | |
| 330 | if (policy->max != max_freq) |
| 331 | cpufreq_verify_within_limits(policy, 0, max_freq); |
| 332 | |
| 333 | return 0; |
| 334 | } |
| 335 | |
Eduardo Valentin | 1b9e352 | 2013-04-17 17:12:02 +0000 | [diff] [blame] | 336 | /* cpufreq cooling device callback functions are defined below */ |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 337 | |
| 338 | /** |
| 339 | * cpufreq_get_max_state - callback function to get the max cooling state. |
| 340 | * @cdev: thermal cooling device pointer. |
| 341 | * @state: fill this variable with the max cooling state. |
Eduardo Valentin | 62c0042 | 2013-04-17 17:12:12 +0000 | [diff] [blame] | 342 | * |
| 343 | * Callback for the thermal cooling device to return the cpufreq |
| 344 | * max cooling state. |
| 345 | * |
| 346 | * Return: 0 on success, an error code otherwise. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 347 | */ |
| 348 | static int cpufreq_get_max_state(struct thermal_cooling_device *cdev, |
| 349 | unsigned long *state) |
| 350 | { |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 351 | struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; |
Laurent Navet [Mali] | bde0066 | 2013-03-12 10:47:50 +0000 | [diff] [blame] | 352 | struct cpumask *mask = &cpufreq_device->allowed_cpus; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 353 | unsigned int cpu; |
Dan Carpenter | 4f89038 | 2013-04-17 07:18:28 +0000 | [diff] [blame] | 354 | unsigned int count = 0; |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 355 | int ret; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 356 | |
Laurent Navet [Mali] | bde0066 | 2013-03-12 10:47:50 +0000 | [diff] [blame] | 357 | cpu = cpumask_any(mask); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 358 | |
Dan Carpenter | 4f89038 | 2013-04-17 07:18:28 +0000 | [diff] [blame] | 359 | ret = get_property(cpu, 0, &count, GET_MAXL); |
hongbo.zhang | 9c51b05 | 2012-10-30 17:48:58 +0100 | [diff] [blame] | 360 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 361 | if (count > 0) |
| 362 | *state = count; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 363 | |
Zhang Rui | fc35b35 | 2013-02-08 13:09:32 +0800 | [diff] [blame] | 364 | return ret; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 365 | } |
| 366 | |
| 367 | /** |
| 368 | * cpufreq_get_cur_state - callback function to get the current cooling state. |
| 369 | * @cdev: thermal cooling device pointer. |
| 370 | * @state: fill this variable with the current cooling state. |
Eduardo Valentin | 3672552 | 2013-04-17 17:12:13 +0000 | [diff] [blame] | 371 | * |
| 372 | * Callback for the thermal cooling device to return the cpufreq |
| 373 | * current cooling state. |
| 374 | * |
| 375 | * Return: 0 on success, an error code otherwise. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 376 | */ |
| 377 | static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev, |
| 378 | unsigned long *state) |
| 379 | { |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 380 | struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 381 | |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 382 | *state = cpufreq_device->cpufreq_state; |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 383 | |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 384 | return 0; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 385 | } |
| 386 | |
| 387 | /** |
| 388 | * cpufreq_set_cur_state - callback function to set the current cooling state. |
| 389 | * @cdev: thermal cooling device pointer. |
| 390 | * @state: set this variable to the current cooling state. |
Eduardo Valentin | 56e05fdb | 2013-04-17 17:12:14 +0000 | [diff] [blame] | 391 | * |
| 392 | * Callback for the thermal cooling device to change the cpufreq |
| 393 | * current cooling state. |
| 394 | * |
| 395 | * Return: 0 on success, an error code otherwise. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 396 | */ |
| 397 | static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev, |
| 398 | unsigned long state) |
| 399 | { |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 400 | struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 401 | |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 402 | return cpufreq_apply_cooling(cpufreq_device, state); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 403 | } |
| 404 | |
| 405 | /* Bind cpufreq callbacks to thermal cooling device ops */ |
| 406 | static struct thermal_cooling_device_ops const cpufreq_cooling_ops = { |
| 407 | .get_max_state = cpufreq_get_max_state, |
| 408 | .get_cur_state = cpufreq_get_cur_state, |
| 409 | .set_cur_state = cpufreq_set_cur_state, |
| 410 | }; |
| 411 | |
| 412 | /* Notifier for cpufreq policy change */ |
| 413 | static struct notifier_block thermal_cpufreq_notifier_block = { |
| 414 | .notifier_call = cpufreq_thermal_notifier, |
| 415 | }; |
| 416 | |
| 417 | /** |
| 418 | * cpufreq_cooling_register - function to create cpufreq cooling device. |
| 419 | * @clip_cpus: cpumask of cpus where the frequency constraints will happen. |
Eduardo Valentin | 12cb08b | 2013-04-17 17:12:15 +0000 | [diff] [blame] | 420 | * |
| 421 | * This interface function registers the cpufreq cooling device with the name |
| 422 | * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq |
| 423 | * cooling devices. |
| 424 | * |
| 425 | * Return: a valid struct thermal_cooling_device pointer on success, |
| 426 | * on failure, it returns a corresponding ERR_PTR(). |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 427 | */ |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 428 | struct thermal_cooling_device * |
| 429 | cpufreq_cooling_register(const struct cpumask *clip_cpus) |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 430 | { |
| 431 | struct thermal_cooling_device *cool_dev; |
| 432 | struct cpufreq_cooling_device *cpufreq_dev = NULL; |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 433 | unsigned int min = 0, max = 0; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 434 | char dev_name[THERMAL_NAME_LENGTH]; |
Jonghwa Lee | a4b6fec | 2012-09-26 09:43:31 +0900 | [diff] [blame] | 435 | int ret = 0, i; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 436 | struct cpufreq_policy policy; |
| 437 | |
Eduardo Valentin | 1b9e352 | 2013-04-17 17:12:02 +0000 | [diff] [blame] | 438 | /* Verify that all the clip cpus have same freq_min, freq_max limit */ |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 439 | for_each_cpu(i, clip_cpus) { |
Eduardo Valentin | 1b9e352 | 2013-04-17 17:12:02 +0000 | [diff] [blame] | 440 | /* continue if cpufreq policy not found and not return error */ |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 441 | if (!cpufreq_get_policy(&policy, i)) |
| 442 | continue; |
| 443 | if (min == 0 && max == 0) { |
| 444 | min = policy.cpuinfo.min_freq; |
| 445 | max = policy.cpuinfo.max_freq; |
| 446 | } else { |
| 447 | if (min != policy.cpuinfo.min_freq || |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 448 | max != policy.cpuinfo.max_freq) |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 449 | return ERR_PTR(-EINVAL); |
hongbo.zhang | 6b6519d | 2012-10-30 17:48:57 +0100 | [diff] [blame] | 450 | } |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 451 | } |
| 452 | cpufreq_dev = kzalloc(sizeof(struct cpufreq_cooling_device), |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 453 | GFP_KERNEL); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 454 | if (!cpufreq_dev) |
| 455 | return ERR_PTR(-ENOMEM); |
| 456 | |
| 457 | cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus); |
| 458 | |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 459 | ret = get_idr(&cpufreq_idr, &cpufreq_dev->id); |
| 460 | if (ret) { |
| 461 | kfree(cpufreq_dev); |
| 462 | return ERR_PTR(-EINVAL); |
| 463 | } |
| 464 | |
Eduardo Valentin | 99871a7 | 2013-04-17 17:12:17 +0000 | [diff] [blame] | 465 | snprintf(dev_name, sizeof(dev_name), "thermal-cpufreq-%d", |
| 466 | cpufreq_dev->id); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 467 | |
| 468 | cool_dev = thermal_cooling_device_register(dev_name, cpufreq_dev, |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 469 | &cpufreq_cooling_ops); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 470 | if (!cool_dev) { |
| 471 | release_idr(&cpufreq_idr, cpufreq_dev->id); |
| 472 | kfree(cpufreq_dev); |
| 473 | return ERR_PTR(-EINVAL); |
| 474 | } |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 475 | cpufreq_dev->cool_dev = cool_dev; |
| 476 | cpufreq_dev->cpufreq_state = 0; |
| 477 | mutex_lock(&cooling_cpufreq_lock); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 478 | |
| 479 | /* Register the notifier for first cpufreq cooling device */ |
| 480 | if (cpufreq_dev_count == 0) |
| 481 | cpufreq_register_notifier(&thermal_cpufreq_notifier_block, |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 482 | CPUFREQ_POLICY_NOTIFIER); |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 483 | cpufreq_dev_count++; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 484 | |
| 485 | mutex_unlock(&cooling_cpufreq_lock); |
Eduardo Valentin | 79491e5 | 2013-04-17 17:11:59 +0000 | [diff] [blame] | 486 | |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 487 | return cool_dev; |
| 488 | } |
Eduardo Valentin | 243dbd9 | 2013-04-17 17:11:57 +0000 | [diff] [blame] | 489 | EXPORT_SYMBOL_GPL(cpufreq_cooling_register); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 490 | |
| 491 | /** |
| 492 | * cpufreq_cooling_unregister - function to remove cpufreq cooling device. |
| 493 | * @cdev: thermal cooling device pointer. |
Eduardo Valentin | 135266b | 2013-04-17 17:12:16 +0000 | [diff] [blame] | 494 | * |
| 495 | * This interface function unregisters the "thermal-cpufreq-%x" cooling device. |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 496 | */ |
| 497 | void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) |
| 498 | { |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 499 | struct cpufreq_cooling_device *cpufreq_dev = cdev->devdata; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 500 | |
| 501 | mutex_lock(&cooling_cpufreq_lock); |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 502 | cpufreq_dev_count--; |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 503 | |
| 504 | /* Unregister the notifier for the last cpufreq cooling device */ |
Eduardo Valentin | 2d9bf71 | 2013-04-17 17:12:18 +0000 | [diff] [blame] | 505 | if (cpufreq_dev_count == 0) |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 506 | cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block, |
Eduardo Valentin | 5fda7f6 | 2013-04-17 17:12:11 +0000 | [diff] [blame] | 507 | CPUFREQ_POLICY_NOTIFIER); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 508 | mutex_unlock(&cooling_cpufreq_lock); |
hongbo.zhang | 160b7d8 | 2012-10-30 17:48:59 +0100 | [diff] [blame] | 509 | |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 510 | thermal_cooling_device_unregister(cpufreq_dev->cool_dev); |
| 511 | release_idr(&cpufreq_idr, cpufreq_dev->id); |
Amit Daniel Kachhap | 0236141 | 2012-08-16 17:11:40 +0530 | [diff] [blame] | 512 | kfree(cpufreq_dev); |
| 513 | } |
Eduardo Valentin | 243dbd9 | 2013-04-17 17:11:57 +0000 | [diff] [blame] | 514 | EXPORT_SYMBOL_GPL(cpufreq_cooling_unregister); |