linux/include/linux/clk-provider.h
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   1/*
   2 *  linux/include/linux/clk-provider.h
   3 *
   4 *  Copyright (c) 2010-2011 Jeremy Kerr <jeremy.kerr@canonical.com>
   5 *  Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 */
  11#ifndef __LINUX_CLK_PROVIDER_H
  12#define __LINUX_CLK_PROVIDER_H
  13
  14#include <linux/io.h>
  15#include <linux/of.h>
  16
  17#ifdef CONFIG_COMMON_CLK
  18
  19/*
  20 * flags used across common struct clk.  these flags should only affect the
  21 * top-level framework.  custom flags for dealing with hardware specifics
  22 * belong in struct clk_foo
  23 */
  24#define CLK_SET_RATE_GATE       BIT(0) /* must be gated across rate change */
  25#define CLK_SET_PARENT_GATE     BIT(1) /* must be gated across re-parent */
  26#define CLK_SET_RATE_PARENT     BIT(2) /* propagate rate change up one level */
  27#define CLK_IGNORE_UNUSED       BIT(3) /* do not gate even if unused */
  28#define CLK_IS_ROOT             BIT(4) /* root clk, has no parent */
  29#define CLK_IS_BASIC            BIT(5) /* Basic clk, can't do a to_clk_foo() */
  30#define CLK_GET_RATE_NOCACHE    BIT(6) /* do not use the cached clk rate */
  31#define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
  32#define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
  33#define CLK_RECALC_NEW_RATES    BIT(9) /* recalc rates after notifications */
  34
  35struct clk;
  36struct clk_hw;
  37struct clk_core;
  38struct dentry;
  39
  40/**
  41 * struct clk_rate_request - Structure encoding the clk constraints that
  42 * a clock user might require.
  43 *
  44 * @rate:               Requested clock rate. This field will be adjusted by
  45 *                      clock drivers according to hardware capabilities.
  46 * @min_rate:           Minimum rate imposed by clk users.
  47 * @max_rate:           Maximum rate a imposed by clk users.
  48 * @best_parent_rate:   The best parent rate a parent can provide to fulfill the
  49 *                      requested constraints.
  50 * @best_parent_hw:     The most appropriate parent clock that fulfills the
  51 *                      requested constraints.
  52 *
  53 */
  54struct clk_rate_request {
  55        unsigned long rate;
  56        unsigned long min_rate;
  57        unsigned long max_rate;
  58        unsigned long best_parent_rate;
  59        struct clk_hw *best_parent_hw;
  60};
  61
  62/**
  63 * struct clk_ops -  Callback operations for hardware clocks; these are to
  64 * be provided by the clock implementation, and will be called by drivers
  65 * through the clk_* api.
  66 *
  67 * @prepare:    Prepare the clock for enabling. This must not return until
  68 *              the clock is fully prepared, and it's safe to call clk_enable.
  69 *              This callback is intended to allow clock implementations to
  70 *              do any initialisation that may sleep. Called with
  71 *              prepare_lock held.
  72 *
  73 * @unprepare:  Release the clock from its prepared state. This will typically
  74 *              undo any work done in the @prepare callback. Called with
  75 *              prepare_lock held.
  76 *
  77 * @is_prepared: Queries the hardware to determine if the clock is prepared.
  78 *              This function is allowed to sleep. Optional, if this op is not
  79 *              set then the prepare count will be used.
  80 *
  81 * @unprepare_unused: Unprepare the clock atomically.  Only called from
  82 *              clk_disable_unused for prepare clocks with special needs.
  83 *              Called with prepare mutex held. This function may sleep.
  84 *
  85 * @enable:     Enable the clock atomically. This must not return until the
  86 *              clock is generating a valid clock signal, usable by consumer
  87 *              devices. Called with enable_lock held. This function must not
  88 *              sleep.
  89 *
  90 * @disable:    Disable the clock atomically. Called with enable_lock held.
  91 *              This function must not sleep.
  92 *
  93 * @is_enabled: Queries the hardware to determine if the clock is enabled.
  94 *              This function must not sleep. Optional, if this op is not
  95 *              set then the enable count will be used.
  96 *
  97 * @disable_unused: Disable the clock atomically.  Only called from
  98 *              clk_disable_unused for gate clocks with special needs.
  99 *              Called with enable_lock held.  This function must not
 100 *              sleep.
 101 *
 102 * @recalc_rate Recalculate the rate of this clock, by querying hardware. The
 103 *              parent rate is an input parameter.  It is up to the caller to
 104 *              ensure that the prepare_mutex is held across this call.
 105 *              Returns the calculated rate.  Optional, but recommended - if
 106 *              this op is not set then clock rate will be initialized to 0.
 107 *
 108 * @round_rate: Given a target rate as input, returns the closest rate actually
 109 *              supported by the clock. The parent rate is an input/output
 110 *              parameter.
 111 *
 112 * @determine_rate: Given a target rate as input, returns the closest rate
 113 *              actually supported by the clock, and optionally the parent clock
 114 *              that should be used to provide the clock rate.
 115 *
 116 * @set_parent: Change the input source of this clock; for clocks with multiple
 117 *              possible parents specify a new parent by passing in the index
 118 *              as a u8 corresponding to the parent in either the .parent_names
 119 *              or .parents arrays.  This function in affect translates an
 120 *              array index into the value programmed into the hardware.
 121 *              Returns 0 on success, -EERROR otherwise.
 122 *
 123 * @get_parent: Queries the hardware to determine the parent of a clock.  The
 124 *              return value is a u8 which specifies the index corresponding to
 125 *              the parent clock.  This index can be applied to either the
 126 *              .parent_names or .parents arrays.  In short, this function
 127 *              translates the parent value read from hardware into an array
 128 *              index.  Currently only called when the clock is initialized by
 129 *              __clk_init.  This callback is mandatory for clocks with
 130 *              multiple parents.  It is optional (and unnecessary) for clocks
 131 *              with 0 or 1 parents.
 132 *
 133 * @set_rate:   Change the rate of this clock. The requested rate is specified
 134 *              by the second argument, which should typically be the return
 135 *              of .round_rate call.  The third argument gives the parent rate
 136 *              which is likely helpful for most .set_rate implementation.
 137 *              Returns 0 on success, -EERROR otherwise.
 138 *
 139 * @set_rate_and_parent: Change the rate and the parent of this clock. The
 140 *              requested rate is specified by the second argument, which
 141 *              should typically be the return of .round_rate call.  The
 142 *              third argument gives the parent rate which is likely helpful
 143 *              for most .set_rate_and_parent implementation. The fourth
 144 *              argument gives the parent index. This callback is optional (and
 145 *              unnecessary) for clocks with 0 or 1 parents as well as
 146 *              for clocks that can tolerate switching the rate and the parent
 147 *              separately via calls to .set_parent and .set_rate.
 148 *              Returns 0 on success, -EERROR otherwise.
 149 *
 150 * @recalc_accuracy: Recalculate the accuracy of this clock. The clock accuracy
 151 *              is expressed in ppb (parts per billion). The parent accuracy is
 152 *              an input parameter.
 153 *              Returns the calculated accuracy.  Optional - if this op is not
 154 *              set then clock accuracy will be initialized to parent accuracy
 155 *              or 0 (perfect clock) if clock has no parent.
 156 *
 157 * @get_phase:  Queries the hardware to get the current phase of a clock.
 158 *              Returned values are 0-359 degrees on success, negative
 159 *              error codes on failure.
 160 *
 161 * @set_phase:  Shift the phase this clock signal in degrees specified
 162 *              by the second argument. Valid values for degrees are
 163 *              0-359. Return 0 on success, otherwise -EERROR.
 164 *
 165 * @init:       Perform platform-specific initialization magic.
 166 *              This is not not used by any of the basic clock types.
 167 *              Please consider other ways of solving initialization problems
 168 *              before using this callback, as its use is discouraged.
 169 *
 170 * @debug_init: Set up type-specific debugfs entries for this clock.  This
 171 *              is called once, after the debugfs directory entry for this
 172 *              clock has been created.  The dentry pointer representing that
 173 *              directory is provided as an argument.  Called with
 174 *              prepare_lock held.  Returns 0 on success, -EERROR otherwise.
 175 *
 176 *
 177 * The clk_enable/clk_disable and clk_prepare/clk_unprepare pairs allow
 178 * implementations to split any work between atomic (enable) and sleepable
 179 * (prepare) contexts.  If enabling a clock requires code that might sleep,
 180 * this must be done in clk_prepare.  Clock enable code that will never be
 181 * called in a sleepable context may be implemented in clk_enable.
 182 *
 183 * Typically, drivers will call clk_prepare when a clock may be needed later
 184 * (eg. when a device is opened), and clk_enable when the clock is actually
 185 * required (eg. from an interrupt). Note that clk_prepare MUST have been
 186 * called before clk_enable.
 187 */
 188struct clk_ops {
 189        int             (*prepare)(struct clk_hw *hw);
 190        void            (*unprepare)(struct clk_hw *hw);
 191        int             (*is_prepared)(struct clk_hw *hw);
 192        void            (*unprepare_unused)(struct clk_hw *hw);
 193        int             (*enable)(struct clk_hw *hw);
 194        void            (*disable)(struct clk_hw *hw);
 195        int             (*is_enabled)(struct clk_hw *hw);
 196        void            (*disable_unused)(struct clk_hw *hw);
 197        unsigned long   (*recalc_rate)(struct clk_hw *hw,
 198                                        unsigned long parent_rate);
 199        long            (*round_rate)(struct clk_hw *hw, unsigned long rate,
 200                                        unsigned long *parent_rate);
 201        int             (*determine_rate)(struct clk_hw *hw,
 202                                          struct clk_rate_request *req);
 203        int             (*set_parent)(struct clk_hw *hw, u8 index);
 204        u8              (*get_parent)(struct clk_hw *hw);
 205        int             (*set_rate)(struct clk_hw *hw, unsigned long rate,
 206                                    unsigned long parent_rate);
 207        int             (*set_rate_and_parent)(struct clk_hw *hw,
 208                                    unsigned long rate,
 209                                    unsigned long parent_rate, u8 index);
 210        unsigned long   (*recalc_accuracy)(struct clk_hw *hw,
 211                                           unsigned long parent_accuracy);
 212        int             (*get_phase)(struct clk_hw *hw);
 213        int             (*set_phase)(struct clk_hw *hw, int degrees);
 214        void            (*init)(struct clk_hw *hw);
 215        int             (*debug_init)(struct clk_hw *hw, struct dentry *dentry);
 216};
 217
 218/**
 219 * struct clk_init_data - holds init data that's common to all clocks and is
 220 * shared between the clock provider and the common clock framework.
 221 *
 222 * @name: clock name
 223 * @ops: operations this clock supports
 224 * @parent_names: array of string names for all possible parents
 225 * @num_parents: number of possible parents
 226 * @flags: framework-level hints and quirks
 227 */
 228struct clk_init_data {
 229        const char              *name;
 230        const struct clk_ops    *ops;
 231        const char              * const *parent_names;
 232        u8                      num_parents;
 233        unsigned long           flags;
 234};
 235
 236/**
 237 * struct clk_hw - handle for traversing from a struct clk to its corresponding
 238 * hardware-specific structure.  struct clk_hw should be declared within struct
 239 * clk_foo and then referenced by the struct clk instance that uses struct
 240 * clk_foo's clk_ops
 241 *
 242 * @core: pointer to the struct clk_core instance that points back to this
 243 * struct clk_hw instance
 244 *
 245 * @clk: pointer to the per-user struct clk instance that can be used to call
 246 * into the clk API
 247 *
 248 * @init: pointer to struct clk_init_data that contains the init data shared
 249 * with the common clock framework.
 250 */
 251struct clk_hw {
 252        struct clk_core *core;
 253        struct clk *clk;
 254        const struct clk_init_data *init;
 255};
 256
 257/*
 258 * DOC: Basic clock implementations common to many platforms
 259 *
 260 * Each basic clock hardware type is comprised of a structure describing the
 261 * clock hardware, implementations of the relevant callbacks in struct clk_ops,
 262 * unique flags for that hardware type, a registration function and an
 263 * alternative macro for static initialization
 264 */
 265
 266/**
 267 * struct clk_fixed_rate - fixed-rate clock
 268 * @hw:         handle between common and hardware-specific interfaces
 269 * @fixed_rate: constant frequency of clock
 270 */
 271struct clk_fixed_rate {
 272        struct          clk_hw hw;
 273        unsigned long   fixed_rate;
 274        unsigned long   fixed_accuracy;
 275        u8              flags;
 276};
 277
 278extern const struct clk_ops clk_fixed_rate_ops;
 279struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
 280                const char *parent_name, unsigned long flags,
 281                unsigned long fixed_rate);
 282struct clk *clk_register_fixed_rate_with_accuracy(struct device *dev,
 283                const char *name, const char *parent_name, unsigned long flags,
 284                unsigned long fixed_rate, unsigned long fixed_accuracy);
 285
 286void of_fixed_clk_setup(struct device_node *np);
 287
 288/**
 289 * struct clk_gate - gating clock
 290 *
 291 * @hw:         handle between common and hardware-specific interfaces
 292 * @reg:        register controlling gate
 293 * @bit_idx:    single bit controlling gate
 294 * @flags:      hardware-specific flags
 295 * @lock:       register lock
 296 *
 297 * Clock which can gate its output.  Implements .enable & .disable
 298 *
 299 * Flags:
 300 * CLK_GATE_SET_TO_DISABLE - by default this clock sets the bit at bit_idx to
 301 *      enable the clock.  Setting this flag does the opposite: setting the bit
 302 *      disable the clock and clearing it enables the clock
 303 * CLK_GATE_HIWORD_MASK - The gate settings are only in lower 16-bit
 304 *      of this register, and mask of gate bits are in higher 16-bit of this
 305 *      register.  While setting the gate bits, higher 16-bit should also be
 306 *      updated to indicate changing gate bits.
 307 */
 308struct clk_gate {
 309        struct clk_hw hw;
 310        void __iomem    *reg;
 311        u8              bit_idx;
 312        u8              flags;
 313        spinlock_t      *lock;
 314};
 315
 316#define CLK_GATE_SET_TO_DISABLE         BIT(0)
 317#define CLK_GATE_HIWORD_MASK            BIT(1)
 318
 319extern const struct clk_ops clk_gate_ops;
 320struct clk *clk_register_gate(struct device *dev, const char *name,
 321                const char *parent_name, unsigned long flags,
 322                void __iomem *reg, u8 bit_idx,
 323                u8 clk_gate_flags, spinlock_t *lock);
 324void clk_unregister_gate(struct clk *clk);
 325
 326struct clk_div_table {
 327        unsigned int    val;
 328        unsigned int    div;
 329};
 330
 331/**
 332 * struct clk_divider - adjustable divider clock
 333 *
 334 * @hw:         handle between common and hardware-specific interfaces
 335 * @reg:        register containing the divider
 336 * @shift:      shift to the divider bit field
 337 * @width:      width of the divider bit field
 338 * @table:      array of value/divider pairs, last entry should have div = 0
 339 * @lock:       register lock
 340 *
 341 * Clock with an adjustable divider affecting its output frequency.  Implements
 342 * .recalc_rate, .set_rate and .round_rate
 343 *
 344 * Flags:
 345 * CLK_DIVIDER_ONE_BASED - by default the divisor is the value read from the
 346 *      register plus one.  If CLK_DIVIDER_ONE_BASED is set then the divider is
 347 *      the raw value read from the register, with the value of zero considered
 348 *      invalid, unless CLK_DIVIDER_ALLOW_ZERO is set.
 349 * CLK_DIVIDER_POWER_OF_TWO - clock divisor is 2 raised to the value read from
 350 *      the hardware register
 351 * CLK_DIVIDER_ALLOW_ZERO - Allow zero divisors.  For dividers which have
 352 *      CLK_DIVIDER_ONE_BASED set, it is possible to end up with a zero divisor.
 353 *      Some hardware implementations gracefully handle this case and allow a
 354 *      zero divisor by not modifying their input clock
 355 *      (divide by one / bypass).
 356 * CLK_DIVIDER_HIWORD_MASK - The divider settings are only in lower 16-bit
 357 *      of this register, and mask of divider bits are in higher 16-bit of this
 358 *      register.  While setting the divider bits, higher 16-bit should also be
 359 *      updated to indicate changing divider bits.
 360 * CLK_DIVIDER_ROUND_CLOSEST - Makes the best calculated divider to be rounded
 361 *      to the closest integer instead of the up one.
 362 * CLK_DIVIDER_READ_ONLY - The divider settings are preconfigured and should
 363 *      not be changed by the clock framework.
 364 * CLK_DIVIDER_MAX_AT_ZERO - For dividers which are like CLK_DIVIDER_ONE_BASED
 365 *      except when the value read from the register is zero, the divisor is
 366 *      2^width of the field.
 367 */
 368struct clk_divider {
 369        struct clk_hw   hw;
 370        void __iomem    *reg;
 371        u8              shift;
 372        u8              width;
 373        u8              flags;
 374        const struct clk_div_table      *table;
 375        spinlock_t      *lock;
 376};
 377
 378#define CLK_DIVIDER_ONE_BASED           BIT(0)
 379#define CLK_DIVIDER_POWER_OF_TWO        BIT(1)
 380#define CLK_DIVIDER_ALLOW_ZERO          BIT(2)
 381#define CLK_DIVIDER_HIWORD_MASK         BIT(3)
 382#define CLK_DIVIDER_ROUND_CLOSEST       BIT(4)
 383#define CLK_DIVIDER_READ_ONLY           BIT(5)
 384#define CLK_DIVIDER_MAX_AT_ZERO         BIT(6)
 385
 386extern const struct clk_ops clk_divider_ops;
 387
 388unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate,
 389                unsigned int val, const struct clk_div_table *table,
 390                unsigned long flags);
 391long divider_round_rate(struct clk_hw *hw, unsigned long rate,
 392                unsigned long *prate, const struct clk_div_table *table,
 393                u8 width, unsigned long flags);
 394int divider_get_val(unsigned long rate, unsigned long parent_rate,
 395                const struct clk_div_table *table, u8 width,
 396                unsigned long flags);
 397
 398struct clk *clk_register_divider(struct device *dev, const char *name,
 399                const char *parent_name, unsigned long flags,
 400                void __iomem *reg, u8 shift, u8 width,
 401                u8 clk_divider_flags, spinlock_t *lock);
 402struct clk *clk_register_divider_table(struct device *dev, const char *name,
 403                const char *parent_name, unsigned long flags,
 404                void __iomem *reg, u8 shift, u8 width,
 405                u8 clk_divider_flags, const struct clk_div_table *table,
 406                spinlock_t *lock);
 407void clk_unregister_divider(struct clk *clk);
 408
 409/**
 410 * struct clk_mux - multiplexer clock
 411 *
 412 * @hw:         handle between common and hardware-specific interfaces
 413 * @reg:        register controlling multiplexer
 414 * @shift:      shift to multiplexer bit field
 415 * @width:      width of mutliplexer bit field
 416 * @flags:      hardware-specific flags
 417 * @lock:       register lock
 418 *
 419 * Clock with multiple selectable parents.  Implements .get_parent, .set_parent
 420 * and .recalc_rate
 421 *
 422 * Flags:
 423 * CLK_MUX_INDEX_ONE - register index starts at 1, not 0
 424 * CLK_MUX_INDEX_BIT - register index is a single bit (power of two)
 425 * CLK_MUX_HIWORD_MASK - The mux settings are only in lower 16-bit of this
 426 *      register, and mask of mux bits are in higher 16-bit of this register.
 427 *      While setting the mux bits, higher 16-bit should also be updated to
 428 *      indicate changing mux bits.
 429 * CLK_MUX_ROUND_CLOSEST - Use the parent rate that is closest to the desired
 430 *      frequency.
 431 */
 432struct clk_mux {
 433        struct clk_hw   hw;
 434        void __iomem    *reg;
 435        u32             *table;
 436        u32             mask;
 437        u8              shift;
 438        u8              flags;
 439        spinlock_t      *lock;
 440};
 441
 442#define CLK_MUX_INDEX_ONE               BIT(0)
 443#define CLK_MUX_INDEX_BIT               BIT(1)
 444#define CLK_MUX_HIWORD_MASK             BIT(2)
 445#define CLK_MUX_READ_ONLY               BIT(3) /* mux can't be changed */
 446#define CLK_MUX_ROUND_CLOSEST           BIT(4)
 447
 448extern const struct clk_ops clk_mux_ops;
 449extern const struct clk_ops clk_mux_ro_ops;
 450
 451struct clk *clk_register_mux(struct device *dev, const char *name,
 452                const char * const *parent_names, u8 num_parents,
 453                unsigned long flags,
 454                void __iomem *reg, u8 shift, u8 width,
 455                u8 clk_mux_flags, spinlock_t *lock);
 456
 457struct clk *clk_register_mux_table(struct device *dev, const char *name,
 458                const char * const *parent_names, u8 num_parents,
 459                unsigned long flags,
 460                void __iomem *reg, u8 shift, u32 mask,
 461                u8 clk_mux_flags, u32 *table, spinlock_t *lock);
 462
 463void clk_unregister_mux(struct clk *clk);
 464
 465void of_fixed_factor_clk_setup(struct device_node *node);
 466
 467/**
 468 * struct clk_fixed_factor - fixed multiplier and divider clock
 469 *
 470 * @hw:         handle between common and hardware-specific interfaces
 471 * @mult:       multiplier
 472 * @div:        divider
 473 *
 474 * Clock with a fixed multiplier and divider. The output frequency is the
 475 * parent clock rate divided by div and multiplied by mult.
 476 * Implements .recalc_rate, .set_rate and .round_rate
 477 */
 478
 479struct clk_fixed_factor {
 480        struct clk_hw   hw;
 481        unsigned int    mult;
 482        unsigned int    div;
 483};
 484
 485extern const struct clk_ops clk_fixed_factor_ops;
 486struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
 487                const char *parent_name, unsigned long flags,
 488                unsigned int mult, unsigned int div);
 489
 490/**
 491 * struct clk_fractional_divider - adjustable fractional divider clock
 492 *
 493 * @hw:         handle between common and hardware-specific interfaces
 494 * @reg:        register containing the divider
 495 * @mshift:     shift to the numerator bit field
 496 * @mwidth:     width of the numerator bit field
 497 * @nshift:     shift to the denominator bit field
 498 * @nwidth:     width of the denominator bit field
 499 * @lock:       register lock
 500 *
 501 * Clock with adjustable fractional divider affecting its output frequency.
 502 */
 503struct clk_fractional_divider {
 504        struct clk_hw   hw;
 505        void __iomem    *reg;
 506        u8              mshift;
 507        u8              mwidth;
 508        u32             mmask;
 509        u8              nshift;
 510        u8              nwidth;
 511        u32             nmask;
 512        u8              flags;
 513        spinlock_t      *lock;
 514};
 515
 516extern const struct clk_ops clk_fractional_divider_ops;
 517struct clk *clk_register_fractional_divider(struct device *dev,
 518                const char *name, const char *parent_name, unsigned long flags,
 519                void __iomem *reg, u8 mshift, u8 mwidth, u8 nshift, u8 nwidth,
 520                u8 clk_divider_flags, spinlock_t *lock);
 521
 522/**
 523 * struct clk_multiplier - adjustable multiplier clock
 524 *
 525 * @hw:         handle between common and hardware-specific interfaces
 526 * @reg:        register containing the multiplier
 527 * @shift:      shift to the multiplier bit field
 528 * @width:      width of the multiplier bit field
 529 * @lock:       register lock
 530 *
 531 * Clock with an adjustable multiplier affecting its output frequency.
 532 * Implements .recalc_rate, .set_rate and .round_rate
 533 *
 534 * Flags:
 535 * CLK_MULTIPLIER_ZERO_BYPASS - By default, the multiplier is the value read
 536 *      from the register, with 0 being a valid value effectively
 537 *      zeroing the output clock rate. If CLK_MULTIPLIER_ZERO_BYPASS is
 538 *      set, then a null multiplier will be considered as a bypass,
 539 *      leaving the parent rate unmodified.
 540 * CLK_MULTIPLIER_ROUND_CLOSEST - Makes the best calculated divider to be
 541 *      rounded to the closest integer instead of the down one.
 542 */
 543struct clk_multiplier {
 544        struct clk_hw   hw;
 545        void __iomem    *reg;
 546        u8              shift;
 547        u8              width;
 548        u8              flags;
 549        spinlock_t      *lock;
 550};
 551
 552#define CLK_MULTIPLIER_ZERO_BYPASS              BIT(0)
 553#define CLK_MULTIPLIER_ROUND_CLOSEST    BIT(1)
 554
 555extern const struct clk_ops clk_multiplier_ops;
 556
 557/***
 558 * struct clk_composite - aggregate clock of mux, divider and gate clocks
 559 *
 560 * @hw:         handle between common and hardware-specific interfaces
 561 * @mux_hw:     handle between composite and hardware-specific mux clock
 562 * @rate_hw:    handle between composite and hardware-specific rate clock
 563 * @gate_hw:    handle between composite and hardware-specific gate clock
 564 * @mux_ops:    clock ops for mux
 565 * @rate_ops:   clock ops for rate
 566 * @gate_ops:   clock ops for gate
 567 */
 568struct clk_composite {
 569        struct clk_hw   hw;
 570        struct clk_ops  ops;
 571
 572        struct clk_hw   *mux_hw;
 573        struct clk_hw   *rate_hw;
 574        struct clk_hw   *gate_hw;
 575
 576        const struct clk_ops    *mux_ops;
 577        const struct clk_ops    *rate_ops;
 578        const struct clk_ops    *gate_ops;
 579};
 580
 581struct clk *clk_register_composite(struct device *dev, const char *name,
 582                const char * const *parent_names, int num_parents,
 583                struct clk_hw *mux_hw, const struct clk_ops *mux_ops,
 584                struct clk_hw *rate_hw, const struct clk_ops *rate_ops,
 585                struct clk_hw *gate_hw, const struct clk_ops *gate_ops,
 586                unsigned long flags);
 587
 588/***
 589 * struct clk_gpio_gate - gpio gated clock
 590 *
 591 * @hw:         handle between common and hardware-specific interfaces
 592 * @gpiod:      gpio descriptor
 593 *
 594 * Clock with a gpio control for enabling and disabling the parent clock.
 595 * Implements .enable, .disable and .is_enabled
 596 */
 597
 598struct clk_gpio {
 599        struct clk_hw   hw;
 600        struct gpio_desc *gpiod;
 601};
 602
 603extern const struct clk_ops clk_gpio_gate_ops;
 604struct clk *clk_register_gpio_gate(struct device *dev, const char *name,
 605                const char *parent_name, unsigned gpio, bool active_low,
 606                unsigned long flags);
 607
 608void of_gpio_clk_gate_setup(struct device_node *node);
 609
 610/**
 611 * struct clk_gpio_mux - gpio controlled clock multiplexer
 612 *
 613 * @hw:         see struct clk_gpio
 614 * @gpiod:      gpio descriptor to select the parent of this clock multiplexer
 615 *
 616 * Clock with a gpio control for selecting the parent clock.
 617 * Implements .get_parent, .set_parent and .determine_rate
 618 */
 619
 620extern const struct clk_ops clk_gpio_mux_ops;
 621struct clk *clk_register_gpio_mux(struct device *dev, const char *name,
 622                const char * const *parent_names, u8 num_parents, unsigned gpio,
 623                bool active_low, unsigned long flags);
 624
 625void of_gpio_mux_clk_setup(struct device_node *node);
 626
 627/**
 628 * clk_register - allocate a new clock, register it and return an opaque cookie
 629 * @dev: device that is registering this clock
 630 * @hw: link to hardware-specific clock data
 631 *
 632 * clk_register is the primary interface for populating the clock tree with new
 633 * clock nodes.  It returns a pointer to the newly allocated struct clk which
 634 * cannot be dereferenced by driver code but may be used in conjuction with the
 635 * rest of the clock API.  In the event of an error clk_register will return an
 636 * error code; drivers must test for an error code after calling clk_register.
 637 */
 638struct clk *clk_register(struct device *dev, struct clk_hw *hw);
 639struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw);
 640
 641void clk_unregister(struct clk *clk);
 642void devm_clk_unregister(struct device *dev, struct clk *clk);
 643
 644/* helper functions */
 645const char *__clk_get_name(const struct clk *clk);
 646const char *clk_hw_get_name(const struct clk_hw *hw);
 647struct clk_hw *__clk_get_hw(struct clk *clk);
 648unsigned int clk_hw_get_num_parents(const struct clk_hw *hw);
 649struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw);
 650struct clk_hw *clk_hw_get_parent_by_index(const struct clk_hw *hw,
 651                                          unsigned int index);
 652unsigned int __clk_get_enable_count(struct clk *clk);
 653unsigned long clk_hw_get_rate(const struct clk_hw *hw);
 654unsigned long __clk_get_flags(struct clk *clk);
 655unsigned long clk_hw_get_flags(const struct clk_hw *hw);
 656bool clk_hw_is_prepared(const struct clk_hw *hw);
 657bool clk_hw_is_enabled(const struct clk_hw *hw);
 658bool __clk_is_enabled(struct clk *clk);
 659struct clk *__clk_lookup(const char *name);
 660int __clk_mux_determine_rate(struct clk_hw *hw,
 661                             struct clk_rate_request *req);
 662int __clk_determine_rate(struct clk_hw *core, struct clk_rate_request *req);
 663int __clk_mux_determine_rate_closest(struct clk_hw *hw,
 664                                     struct clk_rate_request *req);
 665void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent);
 666void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
 667                           unsigned long max_rate);
 668
 669static inline void __clk_hw_set_clk(struct clk_hw *dst, struct clk_hw *src)
 670{
 671        dst->clk = src->clk;
 672        dst->core = src->core;
 673}
 674
 675/*
 676 * FIXME clock api without lock protection
 677 */
 678unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate);
 679
 680struct of_device_id;
 681
 682typedef void (*of_clk_init_cb_t)(struct device_node *);
 683
 684struct clk_onecell_data {
 685        struct clk **clks;
 686        unsigned int clk_num;
 687};
 688
 689extern struct of_device_id __clk_of_table;
 690
 691#define CLK_OF_DECLARE(name, compat, fn) OF_DECLARE_1(clk, name, compat, fn)
 692
 693#ifdef CONFIG_OF
 694int of_clk_add_provider(struct device_node *np,
 695                        struct clk *(*clk_src_get)(struct of_phandle_args *args,
 696                                                   void *data),
 697                        void *data);
 698void of_clk_del_provider(struct device_node *np);
 699struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
 700                                  void *data);
 701struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data);
 702int of_clk_get_parent_count(struct device_node *np);
 703int of_clk_parent_fill(struct device_node *np, const char **parents,
 704                       unsigned int size);
 705const char *of_clk_get_parent_name(struct device_node *np, int index);
 706
 707void of_clk_init(const struct of_device_id *matches);
 708
 709#else /* !CONFIG_OF */
 710
 711static inline int of_clk_add_provider(struct device_node *np,
 712                        struct clk *(*clk_src_get)(struct of_phandle_args *args,
 713                                                   void *data),
 714                        void *data)
 715{
 716        return 0;
 717}
 718#define of_clk_del_provider(np) \
 719        { while (0); }
 720static inline struct clk *of_clk_src_simple_get(
 721        struct of_phandle_args *clkspec, void *data)
 722{
 723        return ERR_PTR(-ENOENT);
 724}
 725static inline struct clk *of_clk_src_onecell_get(
 726        struct of_phandle_args *clkspec, void *data)
 727{
 728        return ERR_PTR(-ENOENT);
 729}
 730static inline int of_clk_get_parent_count(struct device_node *np)
 731{
 732        return 0;
 733}
 734static inline int of_clk_parent_fill(struct device_node *np,
 735                                     const char **parents, unsigned int size)
 736{
 737        return 0;
 738}
 739static inline const char *of_clk_get_parent_name(struct device_node *np,
 740                                                 int index)
 741{
 742        return NULL;
 743}
 744#define of_clk_init(matches) \
 745        { while (0); }
 746#endif /* CONFIG_OF */
 747
 748/*
 749 * wrap access to peripherals in accessor routines
 750 * for improved portability across platforms
 751 */
 752
 753#if IS_ENABLED(CONFIG_PPC)
 754
 755static inline u32 clk_readl(u32 __iomem *reg)
 756{
 757        return ioread32be(reg);
 758}
 759
 760static inline void clk_writel(u32 val, u32 __iomem *reg)
 761{
 762        iowrite32be(val, reg);
 763}
 764
 765#else   /* platform dependent I/O accessors */
 766
 767static inline u32 clk_readl(u32 __iomem *reg)
 768{
 769        return readl(reg);
 770}
 771
 772static inline void clk_writel(u32 val, u32 __iomem *reg)
 773{
 774        writel(val, reg);
 775}
 776
 777#endif  /* platform dependent I/O accessors */
 778
 779#ifdef CONFIG_DEBUG_FS
 780struct dentry *clk_debugfs_add_file(struct clk_hw *hw, char *name, umode_t mode,
 781                                void *data, const struct file_operations *fops);
 782#endif
 783
 784#endif /* CONFIG_COMMON_CLK */
 785#endif /* CLK_PROVIDER_H */
 786