include/dm/pinctrl.h

   1 /*
   2  * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@socionext.com>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #ifndef __PINCTRL_H
   8 #define __PINCTRL_H
   9
  10 /**
  11  * struct pinconf_param - pin config parameters
  12  *
  13  * @property: property name in DT nodes
  14  * @param: ID for this config parameter
  15  * @default_value: default value for this config parameter used in case
  16  *      no value is specified in DT nodes
  17  */
  18 struct pinconf_param {
  19         const char * const property;
  20         unsigned int param;
  21         u32 default_value;
  22 };
  23
  24 /**
  25  * struct pinctrl_ops - pin control operations, to be implemented by
  26  * pin controller drivers.
  27  *
  28  * The @set_state is the only mandatory operation.  You can implement your
  29  * pinctrl driver with its own @set_state.  In this case, the other callbacks
  30  * are not required.  Otherwise, generic pinctrl framework is also available;
  31  * use pinctrl_generic_set_state for @set_state, and implement other operations
  32  * depending on your necessity.
  33  *
  34  * @get_pins_count: return number of selectable named pins available
  35  *      in this driver.  (necessary to parse "pins" property in DTS)
  36  * @get_pin_name: return the pin name of the pin selector,
  37  *      called by the core to figure out which pin it shall do
  38  *      operations to.  (necessary to parse "pins" property in DTS)
  39  * @get_groups_count: return number of selectable named groups available
  40  *      in this driver.  (necessary to parse "groups" property in DTS)
  41  * @get_group_name: return the group name of the group selector,
  42  *      called by the core to figure out which pin group it shall do
  43  *      operations to.  (necessary to parse "groups" property in DTS)
  44  * @get_functions_count: return number of selectable named functions available
  45  *      in this driver.  (necessary for pin-muxing)
  46  * @get_function_name: return the function name of the muxing selector,
  47  *      called by the core to figure out which mux setting it shall map a
  48  *      certain device to.  (necessary for pin-muxing)
  49  * @pinmux_set: enable a certain muxing function with a certain pin.
  50  *      The @func_selector selects a certain function whereas @pin_selector
  51  *      selects a certain pin to be used. On simple controllers one of them
  52  *      may be ignored.  (necessary for pin-muxing against a single pin)
  53  * @pinmux_group_set: enable a certain muxing function with a certain pin
  54  *      group.  The @func_selector selects a certain function whereas
  55  *      @group_selector selects a certain set of pins to be used. On simple
  56  *      controllers one of them may be ignored.
  57  *      (necessary for pin-muxing against a pin group)
  58  * @pinconf_num_params: number of driver-specific parameters to be parsed
  59  *      from device trees  (necessary for pin-configuration)
  60  * @pinconf_params: list of driver_specific parameters to be parsed from
  61  *      device trees  (necessary for pin-configuration)
  62  * @pinconf_set: configure an individual pin with a given parameter.
  63  *      (necessary for pin-configuration against a single pin)
  64  * @pinconf_group_set: configure all pins in a group with a given parameter.
  65  *      (necessary for pin-configuration against a pin group)
  66  * @set_state: do pinctrl operations specified by @config, a pseudo device
  67  *      pointing a config node. (necessary for pinctrl_full)
  68  * @set_state_simple: do needed pinctrl operations for a peripherl @periph.
  69  *      (necessary for pinctrl_simple)
  70  */
  71 struct pinctrl_ops {
  72         int (*get_pins_count)(struct udevice *dev);
  73         const char *(*get_pin_name)(struct udevice *dev, unsigned selector);
  74         int (*get_groups_count)(struct udevice *dev);
  75         const char *(*get_group_name)(struct udevice *dev, unsigned selector);
  76         int (*get_functions_count)(struct udevice *dev);
  77         const char *(*get_function_name)(struct udevice *dev,
  78                                          unsigned selector);
  79         int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
  80                           unsigned func_selector);
  81         int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
  82                                 unsigned func_selector);
  83         unsigned int pinconf_num_params;
  84         const struct pinconf_param *pinconf_params;
  85         int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
  86                            unsigned param, unsigned argument);
  87         int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
  88                                  unsigned param, unsigned argument);
  89         int (*set_state)(struct udevice *dev, struct udevice *config);
  90
  91         /* for pinctrl-simple */
  92         int (*set_state_simple)(struct udevice *dev, struct udevice *periph);
  93         /**
  94          * request() - Request a particular pinctrl function
  95          *
  96          * This activates the selected function.
  97          *
  98          * @dev:        Device to adjust (UCLASS_PINCTRL)
  99          * @func:       Function number (driver-specific)
 100          * @return 0 if OK, -ve on error
 101          */
 102         int (*request)(struct udevice *dev, int func, int flags);
 103
 104         /**
 105         * get_periph_id() - get the peripheral ID for a device
 106         *
 107         * This generally looks at the peripheral's device tree node to work
 108         * out the peripheral ID. The return value is normally interpreted as
 109         * enum periph_id. so long as this is defined by the platform (which it
 110         * should be).
 111         *
 112         * @dev:         Pinctrl device to use for decoding
 113         * @periph:      Device to check
 114         * @return peripheral ID of @periph, or -ENOENT on error
 115         */
 116         int (*get_periph_id)(struct udevice *dev, struct udevice *periph);
 117
 118         /**
 119          * get_gpio_mux() - get the mux value for a particular GPIO
 120          *
 121          * This allows the raw mux value for a GPIO to be obtained. It is
 122          * useful for displaying the function being used by that GPIO, such
 123          * as with the 'gpio' command. This function is internal to the GPIO
 124          * subsystem and should not be used by generic code. Typically it is
 125          * used by a GPIO driver with knowledge of the SoC pinctrl setup.
 126          *
 127         * @dev:         Pinctrl device to use
 128         * @banknum:     GPIO bank number
 129         * @index:       GPIO index within the bank
 130         * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
 131          */
 132         int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);
 133 };
 134
 135 #define pinctrl_get_ops(dev)    ((struct pinctrl_ops *)(dev)->driver->ops)
 136
 137 /**
 138  * Generic pin configuration paramters
 139  *
 140  * enum pin_config_param - possible pin configuration parameters
 141  * @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it
 142  *      weakly drives the last value on a tristate bus, also known as a "bus
 143  *      holder", "bus keeper" or "repeater". This allows another device on the
 144  *      bus to change the value by driving the bus high or low and switching to
 145  *      tristate. The argument is ignored.
 146  * @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a
 147  *      transition from say pull-up to pull-down implies that you disable
 148  *      pull-up in the process, this setting disables all biasing.
 149  * @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance
 150  *      mode, also know as "third-state" (tristate) or "high-Z" or "floating".
 151  *      On output pins this effectively disconnects the pin, which is useful
 152  *      if for example some other pin is going to drive the signal connected
 153  *      to it for a while. Pins used for input are usually always high
 154  *      impedance.
 155  * @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
 156  *      impedance to GROUND). If the argument is != 0 pull-down is enabled,
 157  *      if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
 158  * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
 159  *      on embedded knowledge of the controller hardware, like current mux
 160  *      function. The pull direction and possibly strength too will normally
 161  *      be decided completely inside the hardware block and not be readable
 162  *      from the kernel side.
 163  *      If the argument is != 0 pull up/down is enabled, if it is 0, the
 164  *      configuration is ignored. The proper way to disable it is to use
 165  *      @PIN_CONFIG_BIAS_DISABLE.
 166  * @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high
 167  *      impedance to VDD). If the argument is != 0 pull-up is enabled,
 168  *      if it is 0, pull-up is total, i.e. the pin is connected to VDD.
 169  * @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open
 170  *      collector) which means it is usually wired with other output ports
 171  *      which are then pulled up with an external resistor. Setting this
 172  *      config will enable open drain mode, the argument is ignored.
 173  * @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source
 174  *      (open emitter). Setting this config will enable open source mode, the
 175  *      argument is ignored.
 176  * @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
 177  *      low, this is the most typical case and is typically achieved with two
 178  *      active transistors on the output. Setting this config will enable
 179  *      push-pull mode, the argument is ignored.
 180  * @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current
 181  *      passed as argument. The argument is in mA.
 182  * @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode,
 183  *      which means it will wait for signals to settle when reading inputs. The
 184  *      argument gives the debounce time in usecs. Setting the
 185  *      argument to zero turns debouncing off.
 186  * @PIN_CONFIG_INPUT_ENABLE: enable the pin's input.  Note that this does not
 187  *      affect the pin's ability to drive output.  1 enables input, 0 disables
 188  *      input.
 189  * @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
 190  *      schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
 191  *      the threshold value is given on a custom format as argument when
 192  *      setting pins to this mode.
 193  * @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin.
 194  *      If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
 195  *      schmitt-trigger mode is disabled.
 196  * @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power
 197  *      operation, if several modes of operation are supported these can be
 198  *      passed in the argument on a custom form, else just use argument 1
 199  *      to indicate low power mode, argument 0 turns low power mode off.
 200  * @PIN_CONFIG_OUTPUT_ENABLE: this will enable the pin's output mode
 201  *      without driving a value there. For most platforms this reduces to
 202  *      enable the output buffers and then let the pin controller current
 203  *      configuration (eg. the currently selected mux function) drive values on
 204  *      the line. Use argument 1 to enable output mode, argument 0 to disable
 205  *      it.
 206  * @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a
 207  *      value on the line. Use argument 1 to indicate high level, argument 0 to
 208  *      indicate low level. (Please see Documentation/driver-api/pinctl.rst,
 209  *      section "GPIO mode pitfalls" for a discussion around this parameter.)
 210  * @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power
 211  *      supplies, the argument to this parameter (on a custom format) tells
 212  *      the driver which alternative power source to use.
 213  * @PIN_CONFIG_SLEEP_HARDWARE_STATE: indicate this is sleep related state.
 214  * @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to
 215  *      this parameter (on a custom format) tells the driver which alternative
 216  *      slew rate to use.
 217  * @PIN_CONFIG_SKEW_DELAY: if the pin has programmable skew rate (on inputs)
 218  *      or latch delay (on outputs) this parameter (in a custom format)
 219  *      specifies the clock skew or latch delay. It typically controls how
 220  *      many double inverters are put in front of the line.
 221  * @PIN_CONFIG_END: this is the last enumerator for pin configurations, if
 222  *      you need to pass in custom configurations to the pin controller, use
 223  *      PIN_CONFIG_END+1 as the base offset.
 224  * @PIN_CONFIG_MAX: this is the maximum configuration value that can be
 225  *      presented using the packed format.
 226  */
 227 enum pin_config_param {
 228         PIN_CONFIG_BIAS_BUS_HOLD,
 229         PIN_CONFIG_BIAS_DISABLE,
 230         PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
 231         PIN_CONFIG_BIAS_PULL_DOWN,
 232         PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
 233         PIN_CONFIG_BIAS_PULL_UP,
 234         PIN_CONFIG_DRIVE_OPEN_DRAIN,
 235         PIN_CONFIG_DRIVE_OPEN_SOURCE,
 236         PIN_CONFIG_DRIVE_PUSH_PULL,
 237         PIN_CONFIG_DRIVE_STRENGTH,
 238         PIN_CONFIG_INPUT_DEBOUNCE,
 239         PIN_CONFIG_INPUT_ENABLE,
 240         PIN_CONFIG_INPUT_SCHMITT,
 241         PIN_CONFIG_INPUT_SCHMITT_ENABLE,
 242         PIN_CONFIG_LOW_POWER_MODE,
 243         PIN_CONFIG_OUTPUT_ENABLE,
 244         PIN_CONFIG_OUTPUT,
 245         PIN_CONFIG_POWER_SOURCE,
 246         PIN_CONFIG_SLEEP_HARDWARE_STATE,
 247         PIN_CONFIG_SLEW_RATE,
 248         PIN_CONFIG_SKEW_DELAY,
 249         PIN_CONFIG_END = 0x7F,
 250         PIN_CONFIG_MAX = 0xFF,
 251 };
 252
 253 #if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
 254 /**
 255  * pinctrl_generic_set_state() - generic set_state operation
 256  * Parse the DT node of @config and its children and handle generic properties
 257  * such as "pins", "groups", "functions", and pin configuration parameters.
 258  *
 259  * @pctldev: pinctrl device
 260  * @config: config device (pseudo device), pointing a config node in DTS
 261  * @return: 0 on success, or negative error code on failure
 262  */
 263 int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
 264 #else
 265 static inline int pinctrl_generic_set_state(struct udevice *pctldev,
 266                                             struct udevice *config)
 267 {
 268         return -EINVAL;
 269 }
 270 #endif
 271
 272 #if CONFIG_IS_ENABLED(PINCTRL)
 273 /**
 274  * pinctrl_select_state() - set a device to a given state
 275  *
 276  * @dev: peripheral device
 277  * @statename: state name, like "default"
 278  * @return: 0 on success, or negative error code on failure
 279  */
 280 int pinctrl_select_state(struct udevice *dev, const char *statename);
 281 #else
 282 static inline int pinctrl_select_state(struct udevice *dev,
 283                                        const char *statename)
 284 {
 285         return -EINVAL;
 286 }
 287 #endif
 288
 289 /**
 290  * pinctrl_request() - Request a particular pinctrl function
 291  *
 292  * @dev:        Device to check (UCLASS_PINCTRL)
 293  * @func:       Function number (driver-specific)
 294  * @flags:      Flags (driver-specific)
 295  * @return 0 if OK, -ve on error
 296  */
 297 int pinctrl_request(struct udevice *dev, int func, int flags);
 298
 299 /**
 300  * pinctrl_request_noflags() - Request a particular pinctrl function
 301  *
 302  * This is similar to pinctrl_request() but uses 0 for @flags.
 303  *
 304  * @dev:        Device to check (UCLASS_PINCTRL)
 305  * @func:       Function number (driver-specific)
 306  * @return 0 if OK, -ve on error
 307  */
 308 int pinctrl_request_noflags(struct udevice *dev, int func);
 309
 310 /**
 311  * pinctrl_get_periph_id() - get the peripheral ID for a device
 312  *
 313  * This generally looks at the peripheral's device tree node to work out the
 314  * peripheral ID. The return value is normally interpreted as enum periph_id.
 315  * so long as this is defined by the platform (which it should be).
 316  *
 317  * @dev:        Pinctrl device to use for decoding
 318  * @periph:     Device to check
 319  * @return peripheral ID of @periph, or -ENOENT on error
 320  */
 321 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
 322
 323 /**
 324  * pinctrl_decode_pin_config() - decode pin configuration flags
 325  *
 326  * This decodes some of the PIN_CONFIG values into flags, with each value
 327  * being (1 << pin_cfg). This does not support things with values like the
 328  * slew rate.
 329  *
 330  * @blob:       Device tree blob
 331  * @node:       Node containing the PIN_CONFIG values
 332  * @return decoded flag value, or -ve on error
 333  */
 334 int pinctrl_decode_pin_config(const void *blob, int node);
 335
 336 /**
 337  * pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
 338  *
 339  * This allows the raw mux value for a GPIO to be obtained. It is
 340  * useful for displaying the function being used by that GPIO, such
 341  * as with the 'gpio' command. This function is internal to the GPIO
 342  * subsystem and should not be used by generic code. Typically it is
 343  * used by a GPIO driver with knowledge of the SoC pinctrl setup.
 344  *
 345  * @dev:        Pinctrl device to use
 346  * @banknum:    GPIO bank number
 347  * @index:      GPIO index within the bank
 348  * @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
 349 */
 350 int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
 351
 352 #endif /* __PINCTRL_H */