| 1 | /* |
| 2 | * Generic OPP Interface |
| 3 | * |
| 4 | * Copyright (C) 2009-2010 Texas Instruments Incorporated. |
| 5 | * Nishanth Menon |
| 6 | * Romit Dasgupta |
| 7 | * Kevin Hilman |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License version 2 as |
| 11 | * published by the Free Software Foundation. |
| 12 | */ |
| 13 | |
| 14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 15 | |
| 16 | #include <linux/clk.h> |
| 17 | #include <linux/errno.h> |
| 18 | #include <linux/err.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/device.h> |
| 21 | #include <linux/of.h> |
| 22 | #include <linux/export.h> |
| 23 | #include <linux/regulator/consumer.h> |
| 24 | |
| 25 | #include "opp.h" |
| 26 | |
| 27 | /* |
| 28 | * The root of the list of all opp-tables. All opp_table structures branch off |
| 29 | * from here, with each opp_table containing the list of opps it supports in |
| 30 | * various states of availability. |
| 31 | */ |
| 32 | static LIST_HEAD(opp_tables); |
| 33 | /* Lock to allow exclusive modification to the device and opp lists */ |
| 34 | DEFINE_MUTEX(opp_table_lock); |
| 35 | |
| 36 | #define opp_rcu_lockdep_assert() \ |
| 37 | do { \ |
| 38 | RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ |
| 39 | !lockdep_is_held(&opp_table_lock), \ |
| 40 | "Missing rcu_read_lock() or " \ |
| 41 | "opp_table_lock protection"); \ |
| 42 | } while (0) |
| 43 | |
| 44 | static struct opp_device *_find_opp_dev(const struct device *dev, |
| 45 | struct opp_table *opp_table) |
| 46 | { |
| 47 | struct opp_device *opp_dev; |
| 48 | |
| 49 | list_for_each_entry(opp_dev, &opp_table->dev_list, node) |
| 50 | if (opp_dev->dev == dev) |
| 51 | return opp_dev; |
| 52 | |
| 53 | return NULL; |
| 54 | } |
| 55 | |
| 56 | static struct opp_table *_managed_opp(const struct device_node *np) |
| 57 | { |
| 58 | struct opp_table *opp_table; |
| 59 | |
| 60 | list_for_each_entry_rcu(opp_table, &opp_tables, node) { |
| 61 | if (opp_table->np == np) { |
| 62 | /* |
| 63 | * Multiple devices can point to the same OPP table and |
| 64 | * so will have same node-pointer, np. |
| 65 | * |
| 66 | * But the OPPs will be considered as shared only if the |
| 67 | * OPP table contains a "opp-shared" property. |
| 68 | */ |
| 69 | return opp_table->shared_opp ? opp_table : NULL; |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | return NULL; |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * _find_opp_table() - find opp_table struct using device pointer |
| 78 | * @dev: device pointer used to lookup OPP table |
| 79 | * |
| 80 | * Search OPP table for one containing matching device. Does a RCU reader |
| 81 | * operation to grab the pointer needed. |
| 82 | * |
| 83 | * Return: pointer to 'struct opp_table' if found, otherwise -ENODEV or |
| 84 | * -EINVAL based on type of error. |
| 85 | * |
| 86 | * Locking: For readers, this function must be called under rcu_read_lock(). |
| 87 | * opp_table is a RCU protected pointer, which means that opp_table is valid |
| 88 | * as long as we are under RCU lock. |
| 89 | * |
| 90 | * For Writers, this function must be called with opp_table_lock held. |
| 91 | */ |
| 92 | struct opp_table *_find_opp_table(struct device *dev) |
| 93 | { |
| 94 | struct opp_table *opp_table; |
| 95 | |
| 96 | opp_rcu_lockdep_assert(); |
| 97 | |
| 98 | if (IS_ERR_OR_NULL(dev)) { |
| 99 | pr_err("%s: Invalid parameters\n", __func__); |
| 100 | return ERR_PTR(-EINVAL); |
| 101 | } |
| 102 | |
| 103 | list_for_each_entry_rcu(opp_table, &opp_tables, node) |
| 104 | if (_find_opp_dev(dev, opp_table)) |
| 105 | return opp_table; |
| 106 | |
| 107 | return ERR_PTR(-ENODEV); |
| 108 | } |
| 109 | |
| 110 | /** |
| 111 | * dev_pm_opp_get_voltage() - Gets the voltage corresponding to an opp |
| 112 | * @opp: opp for which voltage has to be returned for |
| 113 | * |
| 114 | * Return: voltage in micro volt corresponding to the opp, else |
| 115 | * return 0 |
| 116 | * |
| 117 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 118 | * protected pointer. This means that opp which could have been fetched by |
| 119 | * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are |
| 120 | * under RCU lock. The pointer returned by the opp_find_freq family must be |
| 121 | * used in the same section as the usage of this function with the pointer |
| 122 | * prior to unlocking with rcu_read_unlock() to maintain the integrity of the |
| 123 | * pointer. |
| 124 | */ |
| 125 | unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) |
| 126 | { |
| 127 | struct dev_pm_opp *tmp_opp; |
| 128 | unsigned long v = 0; |
| 129 | |
| 130 | opp_rcu_lockdep_assert(); |
| 131 | |
| 132 | tmp_opp = rcu_dereference(opp); |
| 133 | if (IS_ERR_OR_NULL(tmp_opp)) |
| 134 | pr_err("%s: Invalid parameters\n", __func__); |
| 135 | else |
| 136 | v = tmp_opp->u_volt; |
| 137 | |
| 138 | return v; |
| 139 | } |
| 140 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage); |
| 141 | |
| 142 | /** |
| 143 | * dev_pm_opp_get_freq() - Gets the frequency corresponding to an available opp |
| 144 | * @opp: opp for which frequency has to be returned for |
| 145 | * |
| 146 | * Return: frequency in hertz corresponding to the opp, else |
| 147 | * return 0 |
| 148 | * |
| 149 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 150 | * protected pointer. This means that opp which could have been fetched by |
| 151 | * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are |
| 152 | * under RCU lock. The pointer returned by the opp_find_freq family must be |
| 153 | * used in the same section as the usage of this function with the pointer |
| 154 | * prior to unlocking with rcu_read_unlock() to maintain the integrity of the |
| 155 | * pointer. |
| 156 | */ |
| 157 | unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp) |
| 158 | { |
| 159 | struct dev_pm_opp *tmp_opp; |
| 160 | unsigned long f = 0; |
| 161 | |
| 162 | opp_rcu_lockdep_assert(); |
| 163 | |
| 164 | tmp_opp = rcu_dereference(opp); |
| 165 | if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) |
| 166 | pr_err("%s: Invalid parameters\n", __func__); |
| 167 | else |
| 168 | f = tmp_opp->rate; |
| 169 | |
| 170 | return f; |
| 171 | } |
| 172 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq); |
| 173 | |
| 174 | /** |
| 175 | * dev_pm_opp_is_turbo() - Returns if opp is turbo OPP or not |
| 176 | * @opp: opp for which turbo mode is being verified |
| 177 | * |
| 178 | * Turbo OPPs are not for normal use, and can be enabled (under certain |
| 179 | * conditions) for short duration of times to finish high throughput work |
| 180 | * quickly. Running on them for longer times may overheat the chip. |
| 181 | * |
| 182 | * Return: true if opp is turbo opp, else false. |
| 183 | * |
| 184 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 185 | * protected pointer. This means that opp which could have been fetched by |
| 186 | * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are |
| 187 | * under RCU lock. The pointer returned by the opp_find_freq family must be |
| 188 | * used in the same section as the usage of this function with the pointer |
| 189 | * prior to unlocking with rcu_read_unlock() to maintain the integrity of the |
| 190 | * pointer. |
| 191 | */ |
| 192 | bool dev_pm_opp_is_turbo(struct dev_pm_opp *opp) |
| 193 | { |
| 194 | struct dev_pm_opp *tmp_opp; |
| 195 | |
| 196 | opp_rcu_lockdep_assert(); |
| 197 | |
| 198 | tmp_opp = rcu_dereference(opp); |
| 199 | if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) { |
| 200 | pr_err("%s: Invalid parameters\n", __func__); |
| 201 | return false; |
| 202 | } |
| 203 | |
| 204 | return tmp_opp->turbo; |
| 205 | } |
| 206 | EXPORT_SYMBOL_GPL(dev_pm_opp_is_turbo); |
| 207 | |
| 208 | /** |
| 209 | * dev_pm_opp_get_max_clock_latency() - Get max clock latency in nanoseconds |
| 210 | * @dev: device for which we do this operation |
| 211 | * |
| 212 | * Return: This function returns the max clock latency in nanoseconds. |
| 213 | * |
| 214 | * Locking: This function takes rcu_read_lock(). |
| 215 | */ |
| 216 | unsigned long dev_pm_opp_get_max_clock_latency(struct device *dev) |
| 217 | { |
| 218 | struct opp_table *opp_table; |
| 219 | unsigned long clock_latency_ns; |
| 220 | |
| 221 | rcu_read_lock(); |
| 222 | |
| 223 | opp_table = _find_opp_table(dev); |
| 224 | if (IS_ERR(opp_table)) |
| 225 | clock_latency_ns = 0; |
| 226 | else |
| 227 | clock_latency_ns = opp_table->clock_latency_ns_max; |
| 228 | |
| 229 | rcu_read_unlock(); |
| 230 | return clock_latency_ns; |
| 231 | } |
| 232 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_clock_latency); |
| 233 | |
| 234 | /** |
| 235 | * dev_pm_opp_get_max_volt_latency() - Get max voltage latency in nanoseconds |
| 236 | * @dev: device for which we do this operation |
| 237 | * |
| 238 | * Return: This function returns the max voltage latency in nanoseconds. |
| 239 | * |
| 240 | * Locking: This function takes rcu_read_lock(). |
| 241 | */ |
| 242 | unsigned long dev_pm_opp_get_max_volt_latency(struct device *dev) |
| 243 | { |
| 244 | struct opp_table *opp_table; |
| 245 | struct dev_pm_opp *opp; |
| 246 | struct regulator *reg; |
| 247 | unsigned long latency_ns = 0; |
| 248 | unsigned long min_uV = ~0, max_uV = 0; |
| 249 | int ret; |
| 250 | |
| 251 | rcu_read_lock(); |
| 252 | |
| 253 | opp_table = _find_opp_table(dev); |
| 254 | if (IS_ERR(opp_table)) { |
| 255 | rcu_read_unlock(); |
| 256 | return 0; |
| 257 | } |
| 258 | |
| 259 | reg = opp_table->regulator; |
| 260 | if (IS_ERR(reg)) { |
| 261 | /* Regulator may not be required for device */ |
| 262 | rcu_read_unlock(); |
| 263 | return 0; |
| 264 | } |
| 265 | |
| 266 | list_for_each_entry_rcu(opp, &opp_table->opp_list, node) { |
| 267 | if (!opp->available) |
| 268 | continue; |
| 269 | |
| 270 | if (opp->u_volt_min < min_uV) |
| 271 | min_uV = opp->u_volt_min; |
| 272 | if (opp->u_volt_max > max_uV) |
| 273 | max_uV = opp->u_volt_max; |
| 274 | } |
| 275 | |
| 276 | rcu_read_unlock(); |
| 277 | |
| 278 | /* |
| 279 | * The caller needs to ensure that opp_table (and hence the regulator) |
| 280 | * isn't freed, while we are executing this routine. |
| 281 | */ |
| 282 | ret = regulator_set_voltage_time(reg, min_uV, max_uV); |
| 283 | if (ret > 0) |
| 284 | latency_ns = ret * 1000; |
| 285 | |
| 286 | return latency_ns; |
| 287 | } |
| 288 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_volt_latency); |
| 289 | |
| 290 | /** |
| 291 | * dev_pm_opp_get_max_transition_latency() - Get max transition latency in |
| 292 | * nanoseconds |
| 293 | * @dev: device for which we do this operation |
| 294 | * |
| 295 | * Return: This function returns the max transition latency, in nanoseconds, to |
| 296 | * switch from one OPP to other. |
| 297 | * |
| 298 | * Locking: This function takes rcu_read_lock(). |
| 299 | */ |
| 300 | unsigned long dev_pm_opp_get_max_transition_latency(struct device *dev) |
| 301 | { |
| 302 | return dev_pm_opp_get_max_volt_latency(dev) + |
| 303 | dev_pm_opp_get_max_clock_latency(dev); |
| 304 | } |
| 305 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_max_transition_latency); |
| 306 | |
| 307 | /** |
| 308 | * dev_pm_opp_get_suspend_opp() - Get suspend opp |
| 309 | * @dev: device for which we do this operation |
| 310 | * |
| 311 | * Return: This function returns pointer to the suspend opp if it is |
| 312 | * defined and available, otherwise it returns NULL. |
| 313 | * |
| 314 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 315 | * protected pointer. The reason for the same is that the opp pointer which is |
| 316 | * returned will remain valid for use with opp_get_{voltage, freq} only while |
| 317 | * under the locked area. The pointer returned must be used prior to unlocking |
| 318 | * with rcu_read_unlock() to maintain the integrity of the pointer. |
| 319 | */ |
| 320 | struct dev_pm_opp *dev_pm_opp_get_suspend_opp(struct device *dev) |
| 321 | { |
| 322 | struct opp_table *opp_table; |
| 323 | |
| 324 | opp_rcu_lockdep_assert(); |
| 325 | |
| 326 | opp_table = _find_opp_table(dev); |
| 327 | if (IS_ERR(opp_table) || !opp_table->suspend_opp || |
| 328 | !opp_table->suspend_opp->available) |
| 329 | return NULL; |
| 330 | |
| 331 | return opp_table->suspend_opp; |
| 332 | } |
| 333 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_suspend_opp); |
| 334 | |
| 335 | /** |
| 336 | * dev_pm_opp_get_opp_count() - Get number of opps available in the opp table |
| 337 | * @dev: device for which we do this operation |
| 338 | * |
| 339 | * Return: This function returns the number of available opps if there are any, |
| 340 | * else returns 0 if none or the corresponding error value. |
| 341 | * |
| 342 | * Locking: This function takes rcu_read_lock(). |
| 343 | */ |
| 344 | int dev_pm_opp_get_opp_count(struct device *dev) |
| 345 | { |
| 346 | struct opp_table *opp_table; |
| 347 | struct dev_pm_opp *temp_opp; |
| 348 | int count = 0; |
| 349 | |
| 350 | rcu_read_lock(); |
| 351 | |
| 352 | opp_table = _find_opp_table(dev); |
| 353 | if (IS_ERR(opp_table)) { |
| 354 | count = PTR_ERR(opp_table); |
| 355 | dev_err(dev, "%s: OPP table not found (%d)\n", |
| 356 | __func__, count); |
| 357 | goto out_unlock; |
| 358 | } |
| 359 | |
| 360 | list_for_each_entry_rcu(temp_opp, &opp_table->opp_list, node) { |
| 361 | if (temp_opp->available) |
| 362 | count++; |
| 363 | } |
| 364 | |
| 365 | out_unlock: |
| 366 | rcu_read_unlock(); |
| 367 | return count; |
| 368 | } |
| 369 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count); |
| 370 | |
| 371 | /** |
| 372 | * dev_pm_opp_find_freq_exact() - search for an exact frequency |
| 373 | * @dev: device for which we do this operation |
| 374 | * @freq: frequency to search for |
| 375 | * @available: true/false - match for available opp |
| 376 | * |
| 377 | * Return: Searches for exact match in the opp table and returns pointer to the |
| 378 | * matching opp if found, else returns ERR_PTR in case of error and should |
| 379 | * be handled using IS_ERR. Error return values can be: |
| 380 | * EINVAL: for bad pointer |
| 381 | * ERANGE: no match found for search |
| 382 | * ENODEV: if device not found in list of registered devices |
| 383 | * |
| 384 | * Note: available is a modifier for the search. if available=true, then the |
| 385 | * match is for exact matching frequency and is available in the stored OPP |
| 386 | * table. if false, the match is for exact frequency which is not available. |
| 387 | * |
| 388 | * This provides a mechanism to enable an opp which is not available currently |
| 389 | * or the opposite as well. |
| 390 | * |
| 391 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 392 | * protected pointer. The reason for the same is that the opp pointer which is |
| 393 | * returned will remain valid for use with opp_get_{voltage, freq} only while |
| 394 | * under the locked area. The pointer returned must be used prior to unlocking |
| 395 | * with rcu_read_unlock() to maintain the integrity of the pointer. |
| 396 | */ |
| 397 | struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev, |
| 398 | unsigned long freq, |
| 399 | bool available) |
| 400 | { |
| 401 | struct opp_table *opp_table; |
| 402 | struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); |
| 403 | |
| 404 | opp_rcu_lockdep_assert(); |
| 405 | |
| 406 | opp_table = _find_opp_table(dev); |
| 407 | if (IS_ERR(opp_table)) { |
| 408 | int r = PTR_ERR(opp_table); |
| 409 | |
| 410 | dev_err(dev, "%s: OPP table not found (%d)\n", __func__, r); |
| 411 | return ERR_PTR(r); |
| 412 | } |
| 413 | |
| 414 | list_for_each_entry_rcu(temp_opp, &opp_table->opp_list, node) { |
| 415 | if (temp_opp->available == available && |
| 416 | temp_opp->rate == freq) { |
| 417 | opp = temp_opp; |
| 418 | break; |
| 419 | } |
| 420 | } |
| 421 | |
| 422 | return opp; |
| 423 | } |
| 424 | EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_exact); |
| 425 | |
| 426 | /** |
| 427 | * dev_pm_opp_find_freq_ceil() - Search for an rounded ceil freq |
| 428 | * @dev: device for which we do this operation |
| 429 | * @freq: Start frequency |
| 430 | * |
| 431 | * Search for the matching ceil *available* OPP from a starting freq |
| 432 | * for a device. |
| 433 | * |
| 434 | * Return: matching *opp and refreshes *freq accordingly, else returns |
| 435 | * ERR_PTR in case of error and should be handled using IS_ERR. Error return |
| 436 | * values can be: |
| 437 | * EINVAL: for bad pointer |
| 438 | * ERANGE: no match found for search |
| 439 | * ENODEV: if device not found in list of registered devices |
| 440 | * |
| 441 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 442 | * protected pointer. The reason for the same is that the opp pointer which is |
| 443 | * returned will remain valid for use with opp_get_{voltage, freq} only while |
| 444 | * under the locked area. The pointer returned must be used prior to unlocking |
| 445 | * with rcu_read_unlock() to maintain the integrity of the pointer. |
| 446 | */ |
| 447 | struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev, |
| 448 | unsigned long *freq) |
| 449 | { |
| 450 | struct opp_table *opp_table; |
| 451 | struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); |
| 452 | |
| 453 | opp_rcu_lockdep_assert(); |
| 454 | |
| 455 | if (!dev || !freq) { |
| 456 | dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); |
| 457 | return ERR_PTR(-EINVAL); |
| 458 | } |
| 459 | |
| 460 | opp_table = _find_opp_table(dev); |
| 461 | if (IS_ERR(opp_table)) |
| 462 | return ERR_CAST(opp_table); |
| 463 | |
| 464 | list_for_each_entry_rcu(temp_opp, &opp_table->opp_list, node) { |
| 465 | if (temp_opp->available && temp_opp->rate >= *freq) { |
| 466 | opp = temp_opp; |
| 467 | *freq = opp->rate; |
| 468 | break; |
| 469 | } |
| 470 | } |
| 471 | |
| 472 | return opp; |
| 473 | } |
| 474 | EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil); |
| 475 | |
| 476 | /** |
| 477 | * dev_pm_opp_find_freq_floor() - Search for a rounded floor freq |
| 478 | * @dev: device for which we do this operation |
| 479 | * @freq: Start frequency |
| 480 | * |
| 481 | * Search for the matching floor *available* OPP from a starting freq |
| 482 | * for a device. |
| 483 | * |
| 484 | * Return: matching *opp and refreshes *freq accordingly, else returns |
| 485 | * ERR_PTR in case of error and should be handled using IS_ERR. Error return |
| 486 | * values can be: |
| 487 | * EINVAL: for bad pointer |
| 488 | * ERANGE: no match found for search |
| 489 | * ENODEV: if device not found in list of registered devices |
| 490 | * |
| 491 | * Locking: This function must be called under rcu_read_lock(). opp is a rcu |
| 492 | * protected pointer. The reason for the same is that the opp pointer which is |
| 493 | * returned will remain valid for use with opp_get_{voltage, freq} only while |
| 494 | * under the locked area. The pointer returned must be used prior to unlocking |
| 495 | * with rcu_read_unlock() to maintain the integrity of the pointer. |
| 496 | */ |
| 497 | struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, |
| 498 | unsigned long *freq) |
| 499 | { |
| 500 | struct opp_table *opp_table; |
| 501 | struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE); |
| 502 | |
| 503 | opp_rcu_lockdep_assert(); |
| 504 | |
| 505 | if (!dev || !freq) { |
| 506 | dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq); |
| 507 | return ERR_PTR(-EINVAL); |
| 508 | } |
| 509 | |
| 510 | opp_table = _find_opp_table(dev); |
| 511 | if (IS_ERR(opp_table)) |
| 512 | return ERR_CAST(opp_table); |
| 513 | |
| 514 | list_for_each_entry_rcu(temp_opp, &opp_table->opp_list, node) { |
| 515 | if (temp_opp->available) { |
| 516 | /* go to the next node, before choosing prev */ |
| 517 | if (temp_opp->rate > *freq) |
| 518 | break; |
| 519 | else |
| 520 | opp = temp_opp; |
| 521 | } |
| 522 | } |
| 523 | if (!IS_ERR(opp)) |
| 524 | *freq = opp->rate; |
| 525 | |
| 526 | return opp; |
| 527 | } |
| 528 | EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor); |
| 529 | |
| 530 | /* |
| 531 | * The caller needs to ensure that opp_table (and hence the clk) isn't freed, |
| 532 | * while clk returned here is used. |
| 533 | */ |
| 534 | static struct clk *_get_opp_clk(struct device *dev) |
| 535 | { |
| 536 | struct opp_table *opp_table; |
| 537 | struct clk *clk; |
| 538 | |
| 539 | rcu_read_lock(); |
| 540 | |
| 541 | opp_table = _find_opp_table(dev); |
| 542 | if (IS_ERR(opp_table)) { |
| 543 | dev_err(dev, "%s: device opp doesn't exist\n", __func__); |
| 544 | clk = ERR_CAST(opp_table); |
| 545 | goto unlock; |
| 546 | } |
| 547 | |
| 548 | clk = opp_table->clk; |
| 549 | if (IS_ERR(clk)) |
| 550 | dev_err(dev, "%s: No clock available for the device\n", |
| 551 | __func__); |
| 552 | |
| 553 | unlock: |
| 554 | rcu_read_unlock(); |
| 555 | return clk; |
| 556 | } |
| 557 | |
| 558 | static int _set_opp_voltage(struct device *dev, struct regulator *reg, |
| 559 | unsigned long u_volt, unsigned long u_volt_min, |
| 560 | unsigned long u_volt_max) |
| 561 | { |
| 562 | int ret; |
| 563 | |
| 564 | /* Regulator not available for device */ |
| 565 | if (IS_ERR(reg)) { |
| 566 | dev_dbg(dev, "%s: regulator not available: %ld\n", __func__, |
| 567 | PTR_ERR(reg)); |
| 568 | return 0; |
| 569 | } |
| 570 | |
| 571 | dev_dbg(dev, "%s: voltages (mV): %lu %lu %lu\n", __func__, u_volt_min, |
| 572 | u_volt, u_volt_max); |
| 573 | |
| 574 | ret = regulator_set_voltage_triplet(reg, u_volt_min, u_volt, |
| 575 | u_volt_max); |
| 576 | if (ret) |
| 577 | dev_err(dev, "%s: failed to set voltage (%lu %lu %lu mV): %d\n", |
| 578 | __func__, u_volt_min, u_volt, u_volt_max, ret); |
| 579 | |
| 580 | return ret; |
| 581 | } |
| 582 | |
| 583 | /** |
| 584 | * dev_pm_opp_set_rate() - Configure new OPP based on frequency |
| 585 | * @dev: device for which we do this operation |
| 586 | * @target_freq: frequency to achieve |
| 587 | * |
| 588 | * This configures the power-supplies and clock source to the levels specified |
| 589 | * by the OPP corresponding to the target_freq. |
| 590 | * |
| 591 | * Locking: This function takes rcu_read_lock(). |
| 592 | */ |
| 593 | int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) |
| 594 | { |
| 595 | struct opp_table *opp_table; |
| 596 | struct dev_pm_opp *old_opp, *opp; |
| 597 | struct regulator *reg; |
| 598 | struct clk *clk; |
| 599 | unsigned long freq, old_freq; |
| 600 | unsigned long u_volt, u_volt_min, u_volt_max; |
| 601 | unsigned long ou_volt, ou_volt_min, ou_volt_max; |
| 602 | int ret; |
| 603 | |
| 604 | if (unlikely(!target_freq)) { |
| 605 | dev_err(dev, "%s: Invalid target frequency %lu\n", __func__, |
| 606 | target_freq); |
| 607 | return -EINVAL; |
| 608 | } |
| 609 | |
| 610 | clk = _get_opp_clk(dev); |
| 611 | if (IS_ERR(clk)) |
| 612 | return PTR_ERR(clk); |
| 613 | |
| 614 | freq = clk_round_rate(clk, target_freq); |
| 615 | if ((long)freq <= 0) |
| 616 | freq = target_freq; |
| 617 | |
| 618 | old_freq = clk_get_rate(clk); |
| 619 | |
| 620 | /* Return early if nothing to do */ |
| 621 | if (old_freq == freq) { |
| 622 | dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to do\n", |
| 623 | __func__, freq); |
| 624 | return 0; |
| 625 | } |
| 626 | |
| 627 | rcu_read_lock(); |
| 628 | |
| 629 | opp_table = _find_opp_table(dev); |
| 630 | if (IS_ERR(opp_table)) { |
| 631 | dev_err(dev, "%s: device opp doesn't exist\n", __func__); |
| 632 | rcu_read_unlock(); |
| 633 | return PTR_ERR(opp_table); |
| 634 | } |
| 635 | |
| 636 | old_opp = dev_pm_opp_find_freq_ceil(dev, &old_freq); |
| 637 | if (!IS_ERR(old_opp)) { |
| 638 | ou_volt = old_opp->u_volt; |
| 639 | ou_volt_min = old_opp->u_volt_min; |
| 640 | ou_volt_max = old_opp->u_volt_max; |
| 641 | } else { |
| 642 | dev_err(dev, "%s: failed to find current OPP for freq %lu (%ld)\n", |
| 643 | __func__, old_freq, PTR_ERR(old_opp)); |
| 644 | } |
| 645 | |
| 646 | opp = dev_pm_opp_find_freq_ceil(dev, &freq); |
| 647 | if (IS_ERR(opp)) { |
| 648 | ret = PTR_ERR(opp); |
| 649 | dev_err(dev, "%s: failed to find OPP for freq %lu (%d)\n", |
| 650 | __func__, freq, ret); |
| 651 | rcu_read_unlock(); |
| 652 | return ret; |
| 653 | } |
| 654 | |
| 655 | u_volt = opp->u_volt; |
| 656 | u_volt_min = opp->u_volt_min; |
| 657 | u_volt_max = opp->u_volt_max; |
| 658 | |
| 659 | reg = opp_table->regulator; |
| 660 | |
| 661 | rcu_read_unlock(); |
| 662 | |
| 663 | /* Scaling up? Scale voltage before frequency */ |
| 664 | if (freq > old_freq) { |
| 665 | ret = _set_opp_voltage(dev, reg, u_volt, u_volt_min, |
| 666 | u_volt_max); |
| 667 | if (ret) |
| 668 | goto restore_voltage; |
| 669 | } |
| 670 | |
| 671 | /* Change frequency */ |
| 672 | |
| 673 | dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n", |
| 674 | __func__, old_freq, freq); |
| 675 | |
| 676 | ret = clk_set_rate(clk, freq); |
| 677 | if (ret) { |
| 678 | dev_err(dev, "%s: failed to set clock rate: %d\n", __func__, |
| 679 | ret); |
| 680 | goto restore_voltage; |
| 681 | } |
| 682 | |
| 683 | /* Scaling down? Scale voltage after frequency */ |
| 684 | if (freq < old_freq) { |
| 685 | ret = _set_opp_voltage(dev, reg, u_volt, u_volt_min, |
| 686 | u_volt_max); |
| 687 | if (ret) |
| 688 | goto restore_freq; |
| 689 | } |
| 690 | |
| 691 | return 0; |
| 692 | |
| 693 | restore_freq: |
| 694 | if (clk_set_rate(clk, old_freq)) |
| 695 | dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n", |
| 696 | __func__, old_freq); |
| 697 | restore_voltage: |
| 698 | /* This shouldn't harm even if the voltages weren't updated earlier */ |
| 699 | if (!IS_ERR(old_opp)) |
| 700 | _set_opp_voltage(dev, reg, ou_volt, ou_volt_min, ou_volt_max); |
| 701 | |
| 702 | return ret; |
| 703 | } |
| 704 | EXPORT_SYMBOL_GPL(dev_pm_opp_set_rate); |
| 705 | |
| 706 | /* OPP-dev Helpers */ |
| 707 | static void _kfree_opp_dev_rcu(struct rcu_head *head) |
| 708 | { |
| 709 | struct opp_device *opp_dev; |
| 710 | |
| 711 | opp_dev = container_of(head, struct opp_device, rcu_head); |
| 712 | kfree_rcu(opp_dev, rcu_head); |
| 713 | } |
| 714 | |
| 715 | static void _remove_opp_dev(struct opp_device *opp_dev, |
| 716 | struct opp_table *opp_table) |
| 717 | { |
| 718 | opp_debug_unregister(opp_dev, opp_table); |
| 719 | list_del(&opp_dev->node); |
| 720 | call_srcu(&opp_table->srcu_head.srcu, &opp_dev->rcu_head, |
| 721 | _kfree_opp_dev_rcu); |
| 722 | } |
| 723 | |
| 724 | struct opp_device *_add_opp_dev(const struct device *dev, |
| 725 | struct opp_table *opp_table) |
| 726 | { |
| 727 | struct opp_device *opp_dev; |
| 728 | int ret; |
| 729 | |
| 730 | opp_dev = kzalloc(sizeof(*opp_dev), GFP_KERNEL); |
| 731 | if (!opp_dev) |
| 732 | return NULL; |
| 733 | |
| 734 | /* Initialize opp-dev */ |
| 735 | opp_dev->dev = dev; |
| 736 | list_add_rcu(&opp_dev->node, &opp_table->dev_list); |
| 737 | |
| 738 | /* Create debugfs entries for the opp_table */ |
| 739 | ret = opp_debug_register(opp_dev, opp_table); |
| 740 | if (ret) |
| 741 | dev_err(dev, "%s: Failed to register opp debugfs (%d)\n", |
| 742 | __func__, ret); |
| 743 | |
| 744 | return opp_dev; |
| 745 | } |
| 746 | |
| 747 | /** |
| 748 | * _add_opp_table() - Find OPP table or allocate a new one |
| 749 | * @dev: device for which we do this operation |
| 750 | * |
| 751 | * It tries to find an existing table first, if it couldn't find one, it |
| 752 | * allocates a new OPP table and returns that. |
| 753 | * |
| 754 | * Return: valid opp_table pointer if success, else NULL. |
| 755 | */ |
| 756 | static struct opp_table *_add_opp_table(struct device *dev) |
| 757 | { |
| 758 | struct opp_table *opp_table; |
| 759 | struct opp_device *opp_dev; |
| 760 | struct device_node *np; |
| 761 | int ret; |
| 762 | |
| 763 | /* Check for existing table for 'dev' first */ |
| 764 | opp_table = _find_opp_table(dev); |
| 765 | if (!IS_ERR(opp_table)) |
| 766 | return opp_table; |
| 767 | |
| 768 | /* |
| 769 | * Allocate a new OPP table. In the infrequent case where a new |
| 770 | * device is needed to be added, we pay this penalty. |
| 771 | */ |
| 772 | opp_table = kzalloc(sizeof(*opp_table), GFP_KERNEL); |
| 773 | if (!opp_table) |
| 774 | return NULL; |
| 775 | |
| 776 | INIT_LIST_HEAD(&opp_table->dev_list); |
| 777 | |
| 778 | opp_dev = _add_opp_dev(dev, opp_table); |
| 779 | if (!opp_dev) { |
| 780 | kfree(opp_table); |
| 781 | return NULL; |
| 782 | } |
| 783 | |
| 784 | /* |
| 785 | * Only required for backward compatibility with v1 bindings, but isn't |
| 786 | * harmful for other cases. And so we do it unconditionally. |
| 787 | */ |
| 788 | np = of_node_get(dev->of_node); |
| 789 | if (np) { |
| 790 | u32 val; |
| 791 | |
| 792 | if (!of_property_read_u32(np, "clock-latency", &val)) |
| 793 | opp_table->clock_latency_ns_max = val; |
| 794 | of_property_read_u32(np, "voltage-tolerance", |
| 795 | &opp_table->voltage_tolerance_v1); |
| 796 | of_node_put(np); |
| 797 | } |
| 798 | |
| 799 | /* Set regulator to a non-NULL error value */ |
| 800 | opp_table->regulator = ERR_PTR(-ENXIO); |
| 801 | |
| 802 | /* Find clk for the device */ |
| 803 | opp_table->clk = clk_get(dev, NULL); |
| 804 | if (IS_ERR(opp_table->clk)) { |
| 805 | ret = PTR_ERR(opp_table->clk); |
| 806 | if (ret != -EPROBE_DEFER) |
| 807 | dev_dbg(dev, "%s: Couldn't find clock: %d\n", __func__, |
| 808 | ret); |
| 809 | } |
| 810 | |
| 811 | srcu_init_notifier_head(&opp_table->srcu_head); |
| 812 | INIT_LIST_HEAD(&opp_table->opp_list); |
| 813 | |
| 814 | /* Secure the device table modification */ |
| 815 | list_add_rcu(&opp_table->node, &opp_tables); |
| 816 | return opp_table; |
| 817 | } |
| 818 | |
| 819 | /** |
| 820 | * _kfree_device_rcu() - Free opp_table RCU handler |
| 821 | * @head: RCU head |
| 822 | */ |
| 823 | static void _kfree_device_rcu(struct rcu_head *head) |
| 824 | { |
| 825 | struct opp_table *opp_table = container_of(head, struct opp_table, |
| 826 | rcu_head); |
| 827 | |
| 828 | kfree_rcu(opp_table, rcu_head); |
| 829 | } |
| 830 | |
| 831 | /** |
| 832 | * _remove_opp_table() - Removes a OPP table |
| 833 | * @opp_table: OPP table to be removed. |
| 834 | * |
| 835 | * Removes/frees OPP table if it doesn't contain any OPPs. |
| 836 | */ |
| 837 | static void _remove_opp_table(struct opp_table *opp_table) |
| 838 | { |
| 839 | struct opp_device *opp_dev; |
| 840 | |
| 841 | if (!list_empty(&opp_table->opp_list)) |
| 842 | return; |
| 843 | |
| 844 | if (opp_table->supported_hw) |
| 845 | return; |
| 846 | |
| 847 | if (opp_table->prop_name) |
| 848 | return; |
| 849 | |
| 850 | if (!IS_ERR(opp_table->regulator)) |
| 851 | return; |
| 852 | |
| 853 | /* Release clk */ |
| 854 | if (!IS_ERR(opp_table->clk)) |
| 855 | clk_put(opp_table->clk); |
| 856 | |
| 857 | opp_dev = list_first_entry(&opp_table->dev_list, struct opp_device, |
| 858 | node); |
| 859 | |
| 860 | _remove_opp_dev(opp_dev, opp_table); |
| 861 | |
| 862 | /* dev_list must be empty now */ |
| 863 | WARN_ON(!list_empty(&opp_table->dev_list)); |
| 864 | |
| 865 | list_del_rcu(&opp_table->node); |
| 866 | call_srcu(&opp_table->srcu_head.srcu, &opp_table->rcu_head, |
| 867 | _kfree_device_rcu); |
| 868 | } |
| 869 | |
| 870 | /** |
| 871 | * _kfree_opp_rcu() - Free OPP RCU handler |
| 872 | * @head: RCU head |
| 873 | */ |
| 874 | static void _kfree_opp_rcu(struct rcu_head *head) |
| 875 | { |
| 876 | struct dev_pm_opp *opp = container_of(head, struct dev_pm_opp, rcu_head); |
| 877 | |
| 878 | kfree_rcu(opp, rcu_head); |
| 879 | } |
| 880 | |
| 881 | /** |
| 882 | * _opp_remove() - Remove an OPP from a table definition |
| 883 | * @opp_table: points back to the opp_table struct this opp belongs to |
| 884 | * @opp: pointer to the OPP to remove |
| 885 | * @notify: OPP_EVENT_REMOVE notification should be sent or not |
| 886 | * |
| 887 | * This function removes an opp definition from the opp table. |
| 888 | * |
| 889 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 890 | * It is assumed that the caller holds required mutex for an RCU updater |
| 891 | * strategy. |
| 892 | */ |
| 893 | static void _opp_remove(struct opp_table *opp_table, |
| 894 | struct dev_pm_opp *opp, bool notify) |
| 895 | { |
| 896 | /* |
| 897 | * Notify the changes in the availability of the operable |
| 898 | * frequency/voltage list. |
| 899 | */ |
| 900 | if (notify) |
| 901 | srcu_notifier_call_chain(&opp_table->srcu_head, |
| 902 | OPP_EVENT_REMOVE, opp); |
| 903 | opp_debug_remove_one(opp); |
| 904 | list_del_rcu(&opp->node); |
| 905 | call_srcu(&opp_table->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu); |
| 906 | |
| 907 | _remove_opp_table(opp_table); |
| 908 | } |
| 909 | |
| 910 | /** |
| 911 | * dev_pm_opp_remove() - Remove an OPP from OPP table |
| 912 | * @dev: device for which we do this operation |
| 913 | * @freq: OPP to remove with matching 'freq' |
| 914 | * |
| 915 | * This function removes an opp from the opp table. |
| 916 | * |
| 917 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 918 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 919 | * to keep the integrity of the internal data structures. Callers should ensure |
| 920 | * that this function is *NOT* called under RCU protection or in contexts where |
| 921 | * mutex cannot be locked. |
| 922 | */ |
| 923 | void dev_pm_opp_remove(struct device *dev, unsigned long freq) |
| 924 | { |
| 925 | struct dev_pm_opp *opp; |
| 926 | struct opp_table *opp_table; |
| 927 | bool found = false; |
| 928 | |
| 929 | /* Hold our table modification lock here */ |
| 930 | mutex_lock(&opp_table_lock); |
| 931 | |
| 932 | opp_table = _find_opp_table(dev); |
| 933 | if (IS_ERR(opp_table)) |
| 934 | goto unlock; |
| 935 | |
| 936 | list_for_each_entry(opp, &opp_table->opp_list, node) { |
| 937 | if (opp->rate == freq) { |
| 938 | found = true; |
| 939 | break; |
| 940 | } |
| 941 | } |
| 942 | |
| 943 | if (!found) { |
| 944 | dev_warn(dev, "%s: Couldn't find OPP with freq: %lu\n", |
| 945 | __func__, freq); |
| 946 | goto unlock; |
| 947 | } |
| 948 | |
| 949 | _opp_remove(opp_table, opp, true); |
| 950 | unlock: |
| 951 | mutex_unlock(&opp_table_lock); |
| 952 | } |
| 953 | EXPORT_SYMBOL_GPL(dev_pm_opp_remove); |
| 954 | |
| 955 | static struct dev_pm_opp *_allocate_opp(struct device *dev, |
| 956 | struct opp_table **opp_table) |
| 957 | { |
| 958 | struct dev_pm_opp *opp; |
| 959 | |
| 960 | /* allocate new OPP node */ |
| 961 | opp = kzalloc(sizeof(*opp), GFP_KERNEL); |
| 962 | if (!opp) |
| 963 | return NULL; |
| 964 | |
| 965 | INIT_LIST_HEAD(&opp->node); |
| 966 | |
| 967 | *opp_table = _add_opp_table(dev); |
| 968 | if (!*opp_table) { |
| 969 | kfree(opp); |
| 970 | return NULL; |
| 971 | } |
| 972 | |
| 973 | return opp; |
| 974 | } |
| 975 | |
| 976 | static bool _opp_supported_by_regulators(struct dev_pm_opp *opp, |
| 977 | struct opp_table *opp_table) |
| 978 | { |
| 979 | struct regulator *reg = opp_table->regulator; |
| 980 | |
| 981 | if (!IS_ERR(reg) && |
| 982 | !regulator_is_supported_voltage(reg, opp->u_volt_min, |
| 983 | opp->u_volt_max)) { |
| 984 | pr_warn("%s: OPP minuV: %lu maxuV: %lu, not supported by regulator\n", |
| 985 | __func__, opp->u_volt_min, opp->u_volt_max); |
| 986 | return false; |
| 987 | } |
| 988 | |
| 989 | return true; |
| 990 | } |
| 991 | |
| 992 | static int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, |
| 993 | struct opp_table *opp_table) |
| 994 | { |
| 995 | struct dev_pm_opp *opp; |
| 996 | struct list_head *head = &opp_table->opp_list; |
| 997 | int ret; |
| 998 | |
| 999 | /* |
| 1000 | * Insert new OPP in order of increasing frequency and discard if |
| 1001 | * already present. |
| 1002 | * |
| 1003 | * Need to use &opp_table->opp_list in the condition part of the 'for' |
| 1004 | * loop, don't replace it with head otherwise it will become an infinite |
| 1005 | * loop. |
| 1006 | */ |
| 1007 | list_for_each_entry_rcu(opp, &opp_table->opp_list, node) { |
| 1008 | if (new_opp->rate > opp->rate) { |
| 1009 | head = &opp->node; |
| 1010 | continue; |
| 1011 | } |
| 1012 | |
| 1013 | if (new_opp->rate < opp->rate) |
| 1014 | break; |
| 1015 | |
| 1016 | /* Duplicate OPPs */ |
| 1017 | dev_warn(dev, "%s: duplicate OPPs detected. Existing: freq: %lu, volt: %lu, enabled: %d. New: freq: %lu, volt: %lu, enabled: %d\n", |
| 1018 | __func__, opp->rate, opp->u_volt, opp->available, |
| 1019 | new_opp->rate, new_opp->u_volt, new_opp->available); |
| 1020 | |
| 1021 | return opp->available && new_opp->u_volt == opp->u_volt ? |
| 1022 | 0 : -EEXIST; |
| 1023 | } |
| 1024 | |
| 1025 | new_opp->opp_table = opp_table; |
| 1026 | list_add_rcu(&new_opp->node, head); |
| 1027 | |
| 1028 | ret = opp_debug_create_one(new_opp, opp_table); |
| 1029 | if (ret) |
| 1030 | dev_err(dev, "%s: Failed to register opp to debugfs (%d)\n", |
| 1031 | __func__, ret); |
| 1032 | |
| 1033 | if (!_opp_supported_by_regulators(new_opp, opp_table)) { |
| 1034 | new_opp->available = false; |
| 1035 | dev_warn(dev, "%s: OPP not supported by regulators (%lu)\n", |
| 1036 | __func__, new_opp->rate); |
| 1037 | } |
| 1038 | |
| 1039 | return 0; |
| 1040 | } |
| 1041 | |
| 1042 | /** |
| 1043 | * _opp_add_v1() - Allocate a OPP based on v1 bindings. |
| 1044 | * @dev: device for which we do this operation |
| 1045 | * @freq: Frequency in Hz for this OPP |
| 1046 | * @u_volt: Voltage in uVolts for this OPP |
| 1047 | * @dynamic: Dynamically added OPPs. |
| 1048 | * |
| 1049 | * This function adds an opp definition to the opp table and returns status. |
| 1050 | * The opp is made available by default and it can be controlled using |
| 1051 | * dev_pm_opp_enable/disable functions and may be removed by dev_pm_opp_remove. |
| 1052 | * |
| 1053 | * NOTE: "dynamic" parameter impacts OPPs added by the dev_pm_opp_of_add_table |
| 1054 | * and freed by dev_pm_opp_of_remove_table. |
| 1055 | * |
| 1056 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1057 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1058 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1059 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1060 | * mutex cannot be locked. |
| 1061 | * |
| 1062 | * Return: |
| 1063 | * 0 On success OR |
| 1064 | * Duplicate OPPs (both freq and volt are same) and opp->available |
| 1065 | * -EEXIST Freq are same and volt are different OR |
| 1066 | * Duplicate OPPs (both freq and volt are same) and !opp->available |
| 1067 | * -ENOMEM Memory allocation failure |
| 1068 | */ |
| 1069 | static int _opp_add_v1(struct device *dev, unsigned long freq, long u_volt, |
| 1070 | bool dynamic) |
| 1071 | { |
| 1072 | struct opp_table *opp_table; |
| 1073 | struct dev_pm_opp *new_opp; |
| 1074 | unsigned long tol; |
| 1075 | int ret; |
| 1076 | |
| 1077 | /* Hold our table modification lock here */ |
| 1078 | mutex_lock(&opp_table_lock); |
| 1079 | |
| 1080 | new_opp = _allocate_opp(dev, &opp_table); |
| 1081 | if (!new_opp) { |
| 1082 | ret = -ENOMEM; |
| 1083 | goto unlock; |
| 1084 | } |
| 1085 | |
| 1086 | /* populate the opp table */ |
| 1087 | new_opp->rate = freq; |
| 1088 | tol = u_volt * opp_table->voltage_tolerance_v1 / 100; |
| 1089 | new_opp->u_volt = u_volt; |
| 1090 | new_opp->u_volt_min = u_volt - tol; |
| 1091 | new_opp->u_volt_max = u_volt + tol; |
| 1092 | new_opp->available = true; |
| 1093 | new_opp->dynamic = dynamic; |
| 1094 | |
| 1095 | ret = _opp_add(dev, new_opp, opp_table); |
| 1096 | if (ret) |
| 1097 | goto free_opp; |
| 1098 | |
| 1099 | mutex_unlock(&opp_table_lock); |
| 1100 | |
| 1101 | /* |
| 1102 | * Notify the changes in the availability of the operable |
| 1103 | * frequency/voltage list. |
| 1104 | */ |
| 1105 | srcu_notifier_call_chain(&opp_table->srcu_head, OPP_EVENT_ADD, new_opp); |
| 1106 | return 0; |
| 1107 | |
| 1108 | free_opp: |
| 1109 | _opp_remove(opp_table, new_opp, false); |
| 1110 | unlock: |
| 1111 | mutex_unlock(&opp_table_lock); |
| 1112 | return ret; |
| 1113 | } |
| 1114 | |
| 1115 | /* TODO: Support multiple regulators */ |
| 1116 | static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, |
| 1117 | struct opp_table *opp_table) |
| 1118 | { |
| 1119 | u32 microvolt[3] = {0}; |
| 1120 | u32 val; |
| 1121 | int count, ret; |
| 1122 | struct property *prop = NULL; |
| 1123 | char name[NAME_MAX]; |
| 1124 | |
| 1125 | /* Search for "opp-microvolt-<name>" */ |
| 1126 | if (opp_table->prop_name) { |
| 1127 | snprintf(name, sizeof(name), "opp-microvolt-%s", |
| 1128 | opp_table->prop_name); |
| 1129 | prop = of_find_property(opp->np, name, NULL); |
| 1130 | } |
| 1131 | |
| 1132 | if (!prop) { |
| 1133 | /* Search for "opp-microvolt" */ |
| 1134 | sprintf(name, "opp-microvolt"); |
| 1135 | prop = of_find_property(opp->np, name, NULL); |
| 1136 | |
| 1137 | /* Missing property isn't a problem, but an invalid entry is */ |
| 1138 | if (!prop) |
| 1139 | return 0; |
| 1140 | } |
| 1141 | |
| 1142 | count = of_property_count_u32_elems(opp->np, name); |
| 1143 | if (count < 0) { |
| 1144 | dev_err(dev, "%s: Invalid %s property (%d)\n", |
| 1145 | __func__, name, count); |
| 1146 | return count; |
| 1147 | } |
| 1148 | |
| 1149 | /* There can be one or three elements here */ |
| 1150 | if (count != 1 && count != 3) { |
| 1151 | dev_err(dev, "%s: Invalid number of elements in %s property (%d)\n", |
| 1152 | __func__, name, count); |
| 1153 | return -EINVAL; |
| 1154 | } |
| 1155 | |
| 1156 | ret = of_property_read_u32_array(opp->np, name, microvolt, count); |
| 1157 | if (ret) { |
| 1158 | dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret); |
| 1159 | return -EINVAL; |
| 1160 | } |
| 1161 | |
| 1162 | opp->u_volt = microvolt[0]; |
| 1163 | |
| 1164 | if (count == 1) { |
| 1165 | opp->u_volt_min = opp->u_volt; |
| 1166 | opp->u_volt_max = opp->u_volt; |
| 1167 | } else { |
| 1168 | opp->u_volt_min = microvolt[1]; |
| 1169 | opp->u_volt_max = microvolt[2]; |
| 1170 | } |
| 1171 | |
| 1172 | /* Search for "opp-microamp-<name>" */ |
| 1173 | prop = NULL; |
| 1174 | if (opp_table->prop_name) { |
| 1175 | snprintf(name, sizeof(name), "opp-microamp-%s", |
| 1176 | opp_table->prop_name); |
| 1177 | prop = of_find_property(opp->np, name, NULL); |
| 1178 | } |
| 1179 | |
| 1180 | if (!prop) { |
| 1181 | /* Search for "opp-microamp" */ |
| 1182 | sprintf(name, "opp-microamp"); |
| 1183 | prop = of_find_property(opp->np, name, NULL); |
| 1184 | } |
| 1185 | |
| 1186 | if (prop && !of_property_read_u32(opp->np, name, &val)) |
| 1187 | opp->u_amp = val; |
| 1188 | |
| 1189 | return 0; |
| 1190 | } |
| 1191 | |
| 1192 | /** |
| 1193 | * dev_pm_opp_set_supported_hw() - Set supported platforms |
| 1194 | * @dev: Device for which supported-hw has to be set. |
| 1195 | * @versions: Array of hierarchy of versions to match. |
| 1196 | * @count: Number of elements in the array. |
| 1197 | * |
| 1198 | * This is required only for the V2 bindings, and it enables a platform to |
| 1199 | * specify the hierarchy of versions it supports. OPP layer will then enable |
| 1200 | * OPPs, which are available for those versions, based on its 'opp-supported-hw' |
| 1201 | * property. |
| 1202 | * |
| 1203 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1204 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1205 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1206 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1207 | * mutex cannot be locked. |
| 1208 | */ |
| 1209 | int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, |
| 1210 | unsigned int count) |
| 1211 | { |
| 1212 | struct opp_table *opp_table; |
| 1213 | int ret = 0; |
| 1214 | |
| 1215 | /* Hold our table modification lock here */ |
| 1216 | mutex_lock(&opp_table_lock); |
| 1217 | |
| 1218 | opp_table = _add_opp_table(dev); |
| 1219 | if (!opp_table) { |
| 1220 | ret = -ENOMEM; |
| 1221 | goto unlock; |
| 1222 | } |
| 1223 | |
| 1224 | /* Make sure there are no concurrent readers while updating opp_table */ |
| 1225 | WARN_ON(!list_empty(&opp_table->opp_list)); |
| 1226 | |
| 1227 | /* Do we already have a version hierarchy associated with opp_table? */ |
| 1228 | if (opp_table->supported_hw) { |
| 1229 | dev_err(dev, "%s: Already have supported hardware list\n", |
| 1230 | __func__); |
| 1231 | ret = -EBUSY; |
| 1232 | goto err; |
| 1233 | } |
| 1234 | |
| 1235 | opp_table->supported_hw = kmemdup(versions, count * sizeof(*versions), |
| 1236 | GFP_KERNEL); |
| 1237 | if (!opp_table->supported_hw) { |
| 1238 | ret = -ENOMEM; |
| 1239 | goto err; |
| 1240 | } |
| 1241 | |
| 1242 | opp_table->supported_hw_count = count; |
| 1243 | mutex_unlock(&opp_table_lock); |
| 1244 | return 0; |
| 1245 | |
| 1246 | err: |
| 1247 | _remove_opp_table(opp_table); |
| 1248 | unlock: |
| 1249 | mutex_unlock(&opp_table_lock); |
| 1250 | |
| 1251 | return ret; |
| 1252 | } |
| 1253 | EXPORT_SYMBOL_GPL(dev_pm_opp_set_supported_hw); |
| 1254 | |
| 1255 | /** |
| 1256 | * dev_pm_opp_put_supported_hw() - Releases resources blocked for supported hw |
| 1257 | * @dev: Device for which supported-hw has to be put. |
| 1258 | * |
| 1259 | * This is required only for the V2 bindings, and is called for a matching |
| 1260 | * dev_pm_opp_set_supported_hw(). Until this is called, the opp_table structure |
| 1261 | * will not be freed. |
| 1262 | * |
| 1263 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1264 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1265 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1266 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1267 | * mutex cannot be locked. |
| 1268 | */ |
| 1269 | void dev_pm_opp_put_supported_hw(struct device *dev) |
| 1270 | { |
| 1271 | struct opp_table *opp_table; |
| 1272 | |
| 1273 | /* Hold our table modification lock here */ |
| 1274 | mutex_lock(&opp_table_lock); |
| 1275 | |
| 1276 | /* Check for existing table for 'dev' first */ |
| 1277 | opp_table = _find_opp_table(dev); |
| 1278 | if (IS_ERR(opp_table)) { |
| 1279 | dev_err(dev, "Failed to find opp_table: %ld\n", |
| 1280 | PTR_ERR(opp_table)); |
| 1281 | goto unlock; |
| 1282 | } |
| 1283 | |
| 1284 | /* Make sure there are no concurrent readers while updating opp_table */ |
| 1285 | WARN_ON(!list_empty(&opp_table->opp_list)); |
| 1286 | |
| 1287 | if (!opp_table->supported_hw) { |
| 1288 | dev_err(dev, "%s: Doesn't have supported hardware list\n", |
| 1289 | __func__); |
| 1290 | goto unlock; |
| 1291 | } |
| 1292 | |
| 1293 | kfree(opp_table->supported_hw); |
| 1294 | opp_table->supported_hw = NULL; |
| 1295 | opp_table->supported_hw_count = 0; |
| 1296 | |
| 1297 | /* Try freeing opp_table if this was the last blocking resource */ |
| 1298 | _remove_opp_table(opp_table); |
| 1299 | |
| 1300 | unlock: |
| 1301 | mutex_unlock(&opp_table_lock); |
| 1302 | } |
| 1303 | EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw); |
| 1304 | |
| 1305 | /** |
| 1306 | * dev_pm_opp_set_prop_name() - Set prop-extn name |
| 1307 | * @dev: Device for which the prop-name has to be set. |
| 1308 | * @name: name to postfix to properties. |
| 1309 | * |
| 1310 | * This is required only for the V2 bindings, and it enables a platform to |
| 1311 | * specify the extn to be used for certain property names. The properties to |
| 1312 | * which the extension will apply are opp-microvolt and opp-microamp. OPP core |
| 1313 | * should postfix the property name with -<name> while looking for them. |
| 1314 | * |
| 1315 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1316 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1317 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1318 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1319 | * mutex cannot be locked. |
| 1320 | */ |
| 1321 | int dev_pm_opp_set_prop_name(struct device *dev, const char *name) |
| 1322 | { |
| 1323 | struct opp_table *opp_table; |
| 1324 | int ret = 0; |
| 1325 | |
| 1326 | /* Hold our table modification lock here */ |
| 1327 | mutex_lock(&opp_table_lock); |
| 1328 | |
| 1329 | opp_table = _add_opp_table(dev); |
| 1330 | if (!opp_table) { |
| 1331 | ret = -ENOMEM; |
| 1332 | goto unlock; |
| 1333 | } |
| 1334 | |
| 1335 | /* Make sure there are no concurrent readers while updating opp_table */ |
| 1336 | WARN_ON(!list_empty(&opp_table->opp_list)); |
| 1337 | |
| 1338 | /* Do we already have a prop-name associated with opp_table? */ |
| 1339 | if (opp_table->prop_name) { |
| 1340 | dev_err(dev, "%s: Already have prop-name %s\n", __func__, |
| 1341 | opp_table->prop_name); |
| 1342 | ret = -EBUSY; |
| 1343 | goto err; |
| 1344 | } |
| 1345 | |
| 1346 | opp_table->prop_name = kstrdup(name, GFP_KERNEL); |
| 1347 | if (!opp_table->prop_name) { |
| 1348 | ret = -ENOMEM; |
| 1349 | goto err; |
| 1350 | } |
| 1351 | |
| 1352 | mutex_unlock(&opp_table_lock); |
| 1353 | return 0; |
| 1354 | |
| 1355 | err: |
| 1356 | _remove_opp_table(opp_table); |
| 1357 | unlock: |
| 1358 | mutex_unlock(&opp_table_lock); |
| 1359 | |
| 1360 | return ret; |
| 1361 | } |
| 1362 | EXPORT_SYMBOL_GPL(dev_pm_opp_set_prop_name); |
| 1363 | |
| 1364 | /** |
| 1365 | * dev_pm_opp_put_prop_name() - Releases resources blocked for prop-name |
| 1366 | * @dev: Device for which the prop-name has to be put. |
| 1367 | * |
| 1368 | * This is required only for the V2 bindings, and is called for a matching |
| 1369 | * dev_pm_opp_set_prop_name(). Until this is called, the opp_table structure |
| 1370 | * will not be freed. |
| 1371 | * |
| 1372 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1373 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1374 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1375 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1376 | * mutex cannot be locked. |
| 1377 | */ |
| 1378 | void dev_pm_opp_put_prop_name(struct device *dev) |
| 1379 | { |
| 1380 | struct opp_table *opp_table; |
| 1381 | |
| 1382 | /* Hold our table modification lock here */ |
| 1383 | mutex_lock(&opp_table_lock); |
| 1384 | |
| 1385 | /* Check for existing table for 'dev' first */ |
| 1386 | opp_table = _find_opp_table(dev); |
| 1387 | if (IS_ERR(opp_table)) { |
| 1388 | dev_err(dev, "Failed to find opp_table: %ld\n", |
| 1389 | PTR_ERR(opp_table)); |
| 1390 | goto unlock; |
| 1391 | } |
| 1392 | |
| 1393 | /* Make sure there are no concurrent readers while updating opp_table */ |
| 1394 | WARN_ON(!list_empty(&opp_table->opp_list)); |
| 1395 | |
| 1396 | if (!opp_table->prop_name) { |
| 1397 | dev_err(dev, "%s: Doesn't have a prop-name\n", __func__); |
| 1398 | goto unlock; |
| 1399 | } |
| 1400 | |
| 1401 | kfree(opp_table->prop_name); |
| 1402 | opp_table->prop_name = NULL; |
| 1403 | |
| 1404 | /* Try freeing opp_table if this was the last blocking resource */ |
| 1405 | _remove_opp_table(opp_table); |
| 1406 | |
| 1407 | unlock: |
| 1408 | mutex_unlock(&opp_table_lock); |
| 1409 | } |
| 1410 | EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name); |
| 1411 | |
| 1412 | /** |
| 1413 | * dev_pm_opp_set_regulator() - Set regulator name for the device |
| 1414 | * @dev: Device for which regulator name is being set. |
| 1415 | * @name: Name of the regulator. |
| 1416 | * |
| 1417 | * In order to support OPP switching, OPP layer needs to know the name of the |
| 1418 | * device's regulator, as the core would be required to switch voltages as well. |
| 1419 | * |
| 1420 | * This must be called before any OPPs are initialized for the device. |
| 1421 | * |
| 1422 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1423 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1424 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1425 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1426 | * mutex cannot be locked. |
| 1427 | */ |
| 1428 | int dev_pm_opp_set_regulator(struct device *dev, const char *name) |
| 1429 | { |
| 1430 | struct opp_table *opp_table; |
| 1431 | struct regulator *reg; |
| 1432 | int ret; |
| 1433 | |
| 1434 | mutex_lock(&opp_table_lock); |
| 1435 | |
| 1436 | opp_table = _add_opp_table(dev); |
| 1437 | if (!opp_table) { |
| 1438 | ret = -ENOMEM; |
| 1439 | goto unlock; |
| 1440 | } |
| 1441 | |
| 1442 | /* This should be called before OPPs are initialized */ |
| 1443 | if (WARN_ON(!list_empty(&opp_table->opp_list))) { |
| 1444 | ret = -EBUSY; |
| 1445 | goto err; |
| 1446 | } |
| 1447 | |
| 1448 | /* Already have a regulator set */ |
| 1449 | if (WARN_ON(!IS_ERR(opp_table->regulator))) { |
| 1450 | ret = -EBUSY; |
| 1451 | goto err; |
| 1452 | } |
| 1453 | /* Allocate the regulator */ |
| 1454 | reg = regulator_get_optional(dev, name); |
| 1455 | if (IS_ERR(reg)) { |
| 1456 | ret = PTR_ERR(reg); |
| 1457 | if (ret != -EPROBE_DEFER) |
| 1458 | dev_err(dev, "%s: no regulator (%s) found: %d\n", |
| 1459 | __func__, name, ret); |
| 1460 | goto err; |
| 1461 | } |
| 1462 | |
| 1463 | opp_table->regulator = reg; |
| 1464 | |
| 1465 | mutex_unlock(&opp_table_lock); |
| 1466 | return 0; |
| 1467 | |
| 1468 | err: |
| 1469 | _remove_opp_table(opp_table); |
| 1470 | unlock: |
| 1471 | mutex_unlock(&opp_table_lock); |
| 1472 | |
| 1473 | return ret; |
| 1474 | } |
| 1475 | EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulator); |
| 1476 | |
| 1477 | /** |
| 1478 | * dev_pm_opp_put_regulator() - Releases resources blocked for regulator |
| 1479 | * @dev: Device for which regulator was set. |
| 1480 | * |
| 1481 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1482 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1483 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1484 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1485 | * mutex cannot be locked. |
| 1486 | */ |
| 1487 | void dev_pm_opp_put_regulator(struct device *dev) |
| 1488 | { |
| 1489 | struct opp_table *opp_table; |
| 1490 | |
| 1491 | mutex_lock(&opp_table_lock); |
| 1492 | |
| 1493 | /* Check for existing table for 'dev' first */ |
| 1494 | opp_table = _find_opp_table(dev); |
| 1495 | if (IS_ERR(opp_table)) { |
| 1496 | dev_err(dev, "Failed to find opp_table: %ld\n", |
| 1497 | PTR_ERR(opp_table)); |
| 1498 | goto unlock; |
| 1499 | } |
| 1500 | |
| 1501 | if (IS_ERR(opp_table->regulator)) { |
| 1502 | dev_err(dev, "%s: Doesn't have regulator set\n", __func__); |
| 1503 | goto unlock; |
| 1504 | } |
| 1505 | |
| 1506 | /* Make sure there are no concurrent readers while updating opp_table */ |
| 1507 | WARN_ON(!list_empty(&opp_table->opp_list)); |
| 1508 | |
| 1509 | regulator_put(opp_table->regulator); |
| 1510 | opp_table->regulator = ERR_PTR(-ENXIO); |
| 1511 | |
| 1512 | /* Try freeing opp_table if this was the last blocking resource */ |
| 1513 | _remove_opp_table(opp_table); |
| 1514 | |
| 1515 | unlock: |
| 1516 | mutex_unlock(&opp_table_lock); |
| 1517 | } |
| 1518 | EXPORT_SYMBOL_GPL(dev_pm_opp_put_regulator); |
| 1519 | |
| 1520 | static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table, |
| 1521 | struct device_node *np) |
| 1522 | { |
| 1523 | unsigned int count = opp_table->supported_hw_count; |
| 1524 | u32 version; |
| 1525 | int ret; |
| 1526 | |
| 1527 | if (!opp_table->supported_hw) |
| 1528 | return true; |
| 1529 | |
| 1530 | while (count--) { |
| 1531 | ret = of_property_read_u32_index(np, "opp-supported-hw", count, |
| 1532 | &version); |
| 1533 | if (ret) { |
| 1534 | dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n", |
| 1535 | __func__, count, ret); |
| 1536 | return false; |
| 1537 | } |
| 1538 | |
| 1539 | /* Both of these are bitwise masks of the versions */ |
| 1540 | if (!(version & opp_table->supported_hw[count])) |
| 1541 | return false; |
| 1542 | } |
| 1543 | |
| 1544 | return true; |
| 1545 | } |
| 1546 | |
| 1547 | /** |
| 1548 | * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings) |
| 1549 | * @dev: device for which we do this operation |
| 1550 | * @np: device node |
| 1551 | * |
| 1552 | * This function adds an opp definition to the opp table and returns status. The |
| 1553 | * opp can be controlled using dev_pm_opp_enable/disable functions and may be |
| 1554 | * removed by dev_pm_opp_remove. |
| 1555 | * |
| 1556 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1557 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1558 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1559 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1560 | * mutex cannot be locked. |
| 1561 | * |
| 1562 | * Return: |
| 1563 | * 0 On success OR |
| 1564 | * Duplicate OPPs (both freq and volt are same) and opp->available |
| 1565 | * -EEXIST Freq are same and volt are different OR |
| 1566 | * Duplicate OPPs (both freq and volt are same) and !opp->available |
| 1567 | * -ENOMEM Memory allocation failure |
| 1568 | * -EINVAL Failed parsing the OPP node |
| 1569 | */ |
| 1570 | static int _opp_add_static_v2(struct device *dev, struct device_node *np) |
| 1571 | { |
| 1572 | struct opp_table *opp_table; |
| 1573 | struct dev_pm_opp *new_opp; |
| 1574 | u64 rate; |
| 1575 | u32 val; |
| 1576 | int ret; |
| 1577 | |
| 1578 | /* Hold our table modification lock here */ |
| 1579 | mutex_lock(&opp_table_lock); |
| 1580 | |
| 1581 | new_opp = _allocate_opp(dev, &opp_table); |
| 1582 | if (!new_opp) { |
| 1583 | ret = -ENOMEM; |
| 1584 | goto unlock; |
| 1585 | } |
| 1586 | |
| 1587 | ret = of_property_read_u64(np, "opp-hz", &rate); |
| 1588 | if (ret < 0) { |
| 1589 | dev_err(dev, "%s: opp-hz not found\n", __func__); |
| 1590 | goto free_opp; |
| 1591 | } |
| 1592 | |
| 1593 | /* Check if the OPP supports hardware's hierarchy of versions or not */ |
| 1594 | if (!_opp_is_supported(dev, opp_table, np)) { |
| 1595 | dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate); |
| 1596 | goto free_opp; |
| 1597 | } |
| 1598 | |
| 1599 | /* |
| 1600 | * Rate is defined as an unsigned long in clk API, and so casting |
| 1601 | * explicitly to its type. Must be fixed once rate is 64 bit |
| 1602 | * guaranteed in clk API. |
| 1603 | */ |
| 1604 | new_opp->rate = (unsigned long)rate; |
| 1605 | new_opp->turbo = of_property_read_bool(np, "turbo-mode"); |
| 1606 | |
| 1607 | new_opp->np = np; |
| 1608 | new_opp->dynamic = false; |
| 1609 | new_opp->available = true; |
| 1610 | |
| 1611 | if (!of_property_read_u32(np, "clock-latency-ns", &val)) |
| 1612 | new_opp->clock_latency_ns = val; |
| 1613 | |
| 1614 | ret = opp_parse_supplies(new_opp, dev, opp_table); |
| 1615 | if (ret) |
| 1616 | goto free_opp; |
| 1617 | |
| 1618 | ret = _opp_add(dev, new_opp, opp_table); |
| 1619 | if (ret) |
| 1620 | goto free_opp; |
| 1621 | |
| 1622 | /* OPP to select on device suspend */ |
| 1623 | if (of_property_read_bool(np, "opp-suspend")) { |
| 1624 | if (opp_table->suspend_opp) { |
| 1625 | dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n", |
| 1626 | __func__, opp_table->suspend_opp->rate, |
| 1627 | new_opp->rate); |
| 1628 | } else { |
| 1629 | new_opp->suspend = true; |
| 1630 | opp_table->suspend_opp = new_opp; |
| 1631 | } |
| 1632 | } |
| 1633 | |
| 1634 | if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max) |
| 1635 | opp_table->clock_latency_ns_max = new_opp->clock_latency_ns; |
| 1636 | |
| 1637 | mutex_unlock(&opp_table_lock); |
| 1638 | |
| 1639 | pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n", |
| 1640 | __func__, new_opp->turbo, new_opp->rate, new_opp->u_volt, |
| 1641 | new_opp->u_volt_min, new_opp->u_volt_max, |
| 1642 | new_opp->clock_latency_ns); |
| 1643 | |
| 1644 | /* |
| 1645 | * Notify the changes in the availability of the operable |
| 1646 | * frequency/voltage list. |
| 1647 | */ |
| 1648 | srcu_notifier_call_chain(&opp_table->srcu_head, OPP_EVENT_ADD, new_opp); |
| 1649 | return 0; |
| 1650 | |
| 1651 | free_opp: |
| 1652 | _opp_remove(opp_table, new_opp, false); |
| 1653 | unlock: |
| 1654 | mutex_unlock(&opp_table_lock); |
| 1655 | return ret; |
| 1656 | } |
| 1657 | |
| 1658 | /** |
| 1659 | * dev_pm_opp_add() - Add an OPP table from a table definitions |
| 1660 | * @dev: device for which we do this operation |
| 1661 | * @freq: Frequency in Hz for this OPP |
| 1662 | * @u_volt: Voltage in uVolts for this OPP |
| 1663 | * |
| 1664 | * This function adds an opp definition to the opp table and returns status. |
| 1665 | * The opp is made available by default and it can be controlled using |
| 1666 | * dev_pm_opp_enable/disable functions. |
| 1667 | * |
| 1668 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1669 | * Hence this function internally uses RCU updater strategy with mutex locks |
| 1670 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1671 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1672 | * mutex cannot be locked. |
| 1673 | * |
| 1674 | * Return: |
| 1675 | * 0 On success OR |
| 1676 | * Duplicate OPPs (both freq and volt are same) and opp->available |
| 1677 | * -EEXIST Freq are same and volt are different OR |
| 1678 | * Duplicate OPPs (both freq and volt are same) and !opp->available |
| 1679 | * -ENOMEM Memory allocation failure |
| 1680 | */ |
| 1681 | int dev_pm_opp_add(struct device *dev, unsigned long freq, unsigned long u_volt) |
| 1682 | { |
| 1683 | return _opp_add_v1(dev, freq, u_volt, true); |
| 1684 | } |
| 1685 | EXPORT_SYMBOL_GPL(dev_pm_opp_add); |
| 1686 | |
| 1687 | /** |
| 1688 | * _opp_set_availability() - helper to set the availability of an opp |
| 1689 | * @dev: device for which we do this operation |
| 1690 | * @freq: OPP frequency to modify availability |
| 1691 | * @availability_req: availability status requested for this opp |
| 1692 | * |
| 1693 | * Set the availability of an OPP with an RCU operation, opp_{enable,disable} |
| 1694 | * share a common logic which is isolated here. |
| 1695 | * |
| 1696 | * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the |
| 1697 | * copy operation, returns 0 if no modification was done OR modification was |
| 1698 | * successful. |
| 1699 | * |
| 1700 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1701 | * Hence this function internally uses RCU updater strategy with mutex locks to |
| 1702 | * keep the integrity of the internal data structures. Callers should ensure |
| 1703 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1704 | * mutex locking or synchronize_rcu() blocking calls cannot be used. |
| 1705 | */ |
| 1706 | static int _opp_set_availability(struct device *dev, unsigned long freq, |
| 1707 | bool availability_req) |
| 1708 | { |
| 1709 | struct opp_table *opp_table; |
| 1710 | struct dev_pm_opp *new_opp, *tmp_opp, *opp = ERR_PTR(-ENODEV); |
| 1711 | int r = 0; |
| 1712 | |
| 1713 | /* keep the node allocated */ |
| 1714 | new_opp = kmalloc(sizeof(*new_opp), GFP_KERNEL); |
| 1715 | if (!new_opp) |
| 1716 | return -ENOMEM; |
| 1717 | |
| 1718 | mutex_lock(&opp_table_lock); |
| 1719 | |
| 1720 | /* Find the opp_table */ |
| 1721 | opp_table = _find_opp_table(dev); |
| 1722 | if (IS_ERR(opp_table)) { |
| 1723 | r = PTR_ERR(opp_table); |
| 1724 | dev_warn(dev, "%s: Device OPP not found (%d)\n", __func__, r); |
| 1725 | goto unlock; |
| 1726 | } |
| 1727 | |
| 1728 | /* Do we have the frequency? */ |
| 1729 | list_for_each_entry(tmp_opp, &opp_table->opp_list, node) { |
| 1730 | if (tmp_opp->rate == freq) { |
| 1731 | opp = tmp_opp; |
| 1732 | break; |
| 1733 | } |
| 1734 | } |
| 1735 | if (IS_ERR(opp)) { |
| 1736 | r = PTR_ERR(opp); |
| 1737 | goto unlock; |
| 1738 | } |
| 1739 | |
| 1740 | /* Is update really needed? */ |
| 1741 | if (opp->available == availability_req) |
| 1742 | goto unlock; |
| 1743 | /* copy the old data over */ |
| 1744 | *new_opp = *opp; |
| 1745 | |
| 1746 | /* plug in new node */ |
| 1747 | new_opp->available = availability_req; |
| 1748 | |
| 1749 | list_replace_rcu(&opp->node, &new_opp->node); |
| 1750 | mutex_unlock(&opp_table_lock); |
| 1751 | call_srcu(&opp_table->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu); |
| 1752 | |
| 1753 | /* Notify the change of the OPP availability */ |
| 1754 | if (availability_req) |
| 1755 | srcu_notifier_call_chain(&opp_table->srcu_head, |
| 1756 | OPP_EVENT_ENABLE, new_opp); |
| 1757 | else |
| 1758 | srcu_notifier_call_chain(&opp_table->srcu_head, |
| 1759 | OPP_EVENT_DISABLE, new_opp); |
| 1760 | |
| 1761 | return 0; |
| 1762 | |
| 1763 | unlock: |
| 1764 | mutex_unlock(&opp_table_lock); |
| 1765 | kfree(new_opp); |
| 1766 | return r; |
| 1767 | } |
| 1768 | |
| 1769 | /** |
| 1770 | * dev_pm_opp_enable() - Enable a specific OPP |
| 1771 | * @dev: device for which we do this operation |
| 1772 | * @freq: OPP frequency to enable |
| 1773 | * |
| 1774 | * Enables a provided opp. If the operation is valid, this returns 0, else the |
| 1775 | * corresponding error value. It is meant to be used for users an OPP available |
| 1776 | * after being temporarily made unavailable with dev_pm_opp_disable. |
| 1777 | * |
| 1778 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1779 | * Hence this function indirectly uses RCU and mutex locks to keep the |
| 1780 | * integrity of the internal data structures. Callers should ensure that |
| 1781 | * this function is *NOT* called under RCU protection or in contexts where |
| 1782 | * mutex locking or synchronize_rcu() blocking calls cannot be used. |
| 1783 | * |
| 1784 | * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the |
| 1785 | * copy operation, returns 0 if no modification was done OR modification was |
| 1786 | * successful. |
| 1787 | */ |
| 1788 | int dev_pm_opp_enable(struct device *dev, unsigned long freq) |
| 1789 | { |
| 1790 | return _opp_set_availability(dev, freq, true); |
| 1791 | } |
| 1792 | EXPORT_SYMBOL_GPL(dev_pm_opp_enable); |
| 1793 | |
| 1794 | /** |
| 1795 | * dev_pm_opp_disable() - Disable a specific OPP |
| 1796 | * @dev: device for which we do this operation |
| 1797 | * @freq: OPP frequency to disable |
| 1798 | * |
| 1799 | * Disables a provided opp. If the operation is valid, this returns |
| 1800 | * 0, else the corresponding error value. It is meant to be a temporary |
| 1801 | * control by users to make this OPP not available until the circumstances are |
| 1802 | * right to make it available again (with a call to dev_pm_opp_enable). |
| 1803 | * |
| 1804 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1805 | * Hence this function indirectly uses RCU and mutex locks to keep the |
| 1806 | * integrity of the internal data structures. Callers should ensure that |
| 1807 | * this function is *NOT* called under RCU protection or in contexts where |
| 1808 | * mutex locking or synchronize_rcu() blocking calls cannot be used. |
| 1809 | * |
| 1810 | * Return: -EINVAL for bad pointers, -ENOMEM if no memory available for the |
| 1811 | * copy operation, returns 0 if no modification was done OR modification was |
| 1812 | * successful. |
| 1813 | */ |
| 1814 | int dev_pm_opp_disable(struct device *dev, unsigned long freq) |
| 1815 | { |
| 1816 | return _opp_set_availability(dev, freq, false); |
| 1817 | } |
| 1818 | EXPORT_SYMBOL_GPL(dev_pm_opp_disable); |
| 1819 | |
| 1820 | /** |
| 1821 | * dev_pm_opp_get_notifier() - find notifier_head of the device with opp |
| 1822 | * @dev: device pointer used to lookup OPP table. |
| 1823 | * |
| 1824 | * Return: pointer to notifier head if found, otherwise -ENODEV or |
| 1825 | * -EINVAL based on type of error casted as pointer. value must be checked |
| 1826 | * with IS_ERR to determine valid pointer or error result. |
| 1827 | * |
| 1828 | * Locking: This function must be called under rcu_read_lock(). opp_table is a |
| 1829 | * RCU protected pointer. The reason for the same is that the opp pointer which |
| 1830 | * is returned will remain valid for use with opp_get_{voltage, freq} only while |
| 1831 | * under the locked area. The pointer returned must be used prior to unlocking |
| 1832 | * with rcu_read_unlock() to maintain the integrity of the pointer. |
| 1833 | */ |
| 1834 | struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev) |
| 1835 | { |
| 1836 | struct opp_table *opp_table = _find_opp_table(dev); |
| 1837 | |
| 1838 | if (IS_ERR(opp_table)) |
| 1839 | return ERR_CAST(opp_table); /* matching type */ |
| 1840 | |
| 1841 | return &opp_table->srcu_head; |
| 1842 | } |
| 1843 | EXPORT_SYMBOL_GPL(dev_pm_opp_get_notifier); |
| 1844 | |
| 1845 | #ifdef CONFIG_OF |
| 1846 | /** |
| 1847 | * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT |
| 1848 | * entries |
| 1849 | * @dev: device pointer used to lookup OPP table. |
| 1850 | * |
| 1851 | * Free OPPs created using static entries present in DT. |
| 1852 | * |
| 1853 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 1854 | * Hence this function indirectly uses RCU updater strategy with mutex locks |
| 1855 | * to keep the integrity of the internal data structures. Callers should ensure |
| 1856 | * that this function is *NOT* called under RCU protection or in contexts where |
| 1857 | * mutex cannot be locked. |
| 1858 | */ |
| 1859 | void dev_pm_opp_of_remove_table(struct device *dev) |
| 1860 | { |
| 1861 | struct opp_table *opp_table; |
| 1862 | struct dev_pm_opp *opp, *tmp; |
| 1863 | |
| 1864 | /* Hold our table modification lock here */ |
| 1865 | mutex_lock(&opp_table_lock); |
| 1866 | |
| 1867 | /* Check for existing table for 'dev' */ |
| 1868 | opp_table = _find_opp_table(dev); |
| 1869 | if (IS_ERR(opp_table)) { |
| 1870 | int error = PTR_ERR(opp_table); |
| 1871 | |
| 1872 | if (error != -ENODEV) |
| 1873 | WARN(1, "%s: opp_table: %d\n", |
| 1874 | IS_ERR_OR_NULL(dev) ? |
| 1875 | "Invalid device" : dev_name(dev), |
| 1876 | error); |
| 1877 | goto unlock; |
| 1878 | } |
| 1879 | |
| 1880 | /* Find if opp_table manages a single device */ |
| 1881 | if (list_is_singular(&opp_table->dev_list)) { |
| 1882 | /* Free static OPPs */ |
| 1883 | list_for_each_entry_safe(opp, tmp, &opp_table->opp_list, node) { |
| 1884 | if (!opp->dynamic) |
| 1885 | _opp_remove(opp_table, opp, true); |
| 1886 | } |
| 1887 | } else { |
| 1888 | _remove_opp_dev(_find_opp_dev(dev, opp_table), opp_table); |
| 1889 | } |
| 1890 | |
| 1891 | unlock: |
| 1892 | mutex_unlock(&opp_table_lock); |
| 1893 | } |
| 1894 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table); |
| 1895 | |
| 1896 | /* Returns opp descriptor node for a device, caller must do of_node_put() */ |
| 1897 | struct device_node *_of_get_opp_desc_node(struct device *dev) |
| 1898 | { |
| 1899 | /* |
| 1900 | * TODO: Support for multiple OPP tables. |
| 1901 | * |
| 1902 | * There should be only ONE phandle present in "operating-points-v2" |
| 1903 | * property. |
| 1904 | */ |
| 1905 | |
| 1906 | return of_parse_phandle(dev->of_node, "operating-points-v2", 0); |
| 1907 | } |
| 1908 | |
| 1909 | /* Initializes OPP tables based on new bindings */ |
| 1910 | static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np) |
| 1911 | { |
| 1912 | struct device_node *np; |
| 1913 | struct opp_table *opp_table; |
| 1914 | int ret = 0, count = 0; |
| 1915 | |
| 1916 | mutex_lock(&opp_table_lock); |
| 1917 | |
| 1918 | opp_table = _managed_opp(opp_np); |
| 1919 | if (opp_table) { |
| 1920 | /* OPPs are already managed */ |
| 1921 | if (!_add_opp_dev(dev, opp_table)) |
| 1922 | ret = -ENOMEM; |
| 1923 | mutex_unlock(&opp_table_lock); |
| 1924 | return ret; |
| 1925 | } |
| 1926 | mutex_unlock(&opp_table_lock); |
| 1927 | |
| 1928 | /* We have opp-table node now, iterate over it and add OPPs */ |
| 1929 | for_each_available_child_of_node(opp_np, np) { |
| 1930 | count++; |
| 1931 | |
| 1932 | ret = _opp_add_static_v2(dev, np); |
| 1933 | if (ret) { |
| 1934 | dev_err(dev, "%s: Failed to add OPP, %d\n", __func__, |
| 1935 | ret); |
| 1936 | goto free_table; |
| 1937 | } |
| 1938 | } |
| 1939 | |
| 1940 | /* There should be one of more OPP defined */ |
| 1941 | if (WARN_ON(!count)) |
| 1942 | return -ENOENT; |
| 1943 | |
| 1944 | mutex_lock(&opp_table_lock); |
| 1945 | |
| 1946 | opp_table = _find_opp_table(dev); |
| 1947 | if (WARN_ON(IS_ERR(opp_table))) { |
| 1948 | ret = PTR_ERR(opp_table); |
| 1949 | mutex_unlock(&opp_table_lock); |
| 1950 | goto free_table; |
| 1951 | } |
| 1952 | |
| 1953 | opp_table->np = opp_np; |
| 1954 | opp_table->shared_opp = of_property_read_bool(opp_np, "opp-shared"); |
| 1955 | |
| 1956 | mutex_unlock(&opp_table_lock); |
| 1957 | |
| 1958 | return 0; |
| 1959 | |
| 1960 | free_table: |
| 1961 | dev_pm_opp_of_remove_table(dev); |
| 1962 | |
| 1963 | return ret; |
| 1964 | } |
| 1965 | |
| 1966 | /* Initializes OPP tables based on old-deprecated bindings */ |
| 1967 | static int _of_add_opp_table_v1(struct device *dev) |
| 1968 | { |
| 1969 | const struct property *prop; |
| 1970 | const __be32 *val; |
| 1971 | int nr; |
| 1972 | |
| 1973 | prop = of_find_property(dev->of_node, "operating-points", NULL); |
| 1974 | if (!prop) |
| 1975 | return -ENODEV; |
| 1976 | if (!prop->value) |
| 1977 | return -ENODATA; |
| 1978 | |
| 1979 | /* |
| 1980 | * Each OPP is a set of tuples consisting of frequency and |
| 1981 | * voltage like <freq-kHz vol-uV>. |
| 1982 | */ |
| 1983 | nr = prop->length / sizeof(u32); |
| 1984 | if (nr % 2) { |
| 1985 | dev_err(dev, "%s: Invalid OPP table\n", __func__); |
| 1986 | return -EINVAL; |
| 1987 | } |
| 1988 | |
| 1989 | val = prop->value; |
| 1990 | while (nr) { |
| 1991 | unsigned long freq = be32_to_cpup(val++) * 1000; |
| 1992 | unsigned long volt = be32_to_cpup(val++); |
| 1993 | |
| 1994 | if (_opp_add_v1(dev, freq, volt, false)) |
| 1995 | dev_warn(dev, "%s: Failed to add OPP %ld\n", |
| 1996 | __func__, freq); |
| 1997 | nr -= 2; |
| 1998 | } |
| 1999 | |
| 2000 | return 0; |
| 2001 | } |
| 2002 | |
| 2003 | /** |
| 2004 | * dev_pm_opp_of_add_table() - Initialize opp table from device tree |
| 2005 | * @dev: device pointer used to lookup OPP table. |
| 2006 | * |
| 2007 | * Register the initial OPP table with the OPP library for given device. |
| 2008 | * |
| 2009 | * Locking: The internal opp_table and opp structures are RCU protected. |
| 2010 | * Hence this function indirectly uses RCU updater strategy with mutex locks |
| 2011 | * to keep the integrity of the internal data structures. Callers should ensure |
| 2012 | * that this function is *NOT* called under RCU protection or in contexts where |
| 2013 | * mutex cannot be locked. |
| 2014 | * |
| 2015 | * Return: |
| 2016 | * 0 On success OR |
| 2017 | * Duplicate OPPs (both freq and volt are same) and opp->available |
| 2018 | * -EEXIST Freq are same and volt are different OR |
| 2019 | * Duplicate OPPs (both freq and volt are same) and !opp->available |
| 2020 | * -ENOMEM Memory allocation failure |
| 2021 | * -ENODEV when 'operating-points' property is not found or is invalid data |
| 2022 | * in device node. |
| 2023 | * -ENODATA when empty 'operating-points' property is found |
| 2024 | * -EINVAL when invalid entries are found in opp-v2 table |
| 2025 | */ |
| 2026 | int dev_pm_opp_of_add_table(struct device *dev) |
| 2027 | { |
| 2028 | struct device_node *opp_np; |
| 2029 | int ret; |
| 2030 | |
| 2031 | /* |
| 2032 | * OPPs have two version of bindings now. The older one is deprecated, |
| 2033 | * try for the new binding first. |
| 2034 | */ |
| 2035 | opp_np = _of_get_opp_desc_node(dev); |
| 2036 | if (!opp_np) { |
| 2037 | /* |
| 2038 | * Try old-deprecated bindings for backward compatibility with |
| 2039 | * older dtbs. |
| 2040 | */ |
| 2041 | return _of_add_opp_table_v1(dev); |
| 2042 | } |
| 2043 | |
| 2044 | ret = _of_add_opp_table_v2(dev, opp_np); |
| 2045 | of_node_put(opp_np); |
| 2046 | |
| 2047 | return ret; |
| 2048 | } |
| 2049 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table); |
| 2050 | #endif |