mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
77eaa19e73
GPIO drivers want to be able to show if a pin is enabled for input, output, or is being used by another function. Some drivers can easily find this and the code is included in the driver. For some SoCs this is more complex. Conceptually this should be handled by pinctrl rather than GPIO. Most pinctrl drivers will have this feature anyway. Add a method by which a GPIO driver can obtain the pin mux value given a GPIO reference. This avoids repeating the code in two places. Signed-off-by: Simon Glass <sjg@chromium.org>
333 lines
14 KiB
C
333 lines
14 KiB
C
/*
|
|
* Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#ifndef __PINCTRL_H
|
|
#define __PINCTRL_H
|
|
|
|
/**
|
|
* struct pinconf_param - pin config parameters
|
|
*
|
|
* @property: property name in DT nodes
|
|
* @param: ID for this config parameter
|
|
* @default_value: default value for this config parameter used in case
|
|
* no value is specified in DT nodes
|
|
*/
|
|
struct pinconf_param {
|
|
const char * const property;
|
|
unsigned int param;
|
|
u32 default_value;
|
|
};
|
|
|
|
/**
|
|
* struct pinctrl_ops - pin control operations, to be implemented by
|
|
* pin controller drivers.
|
|
*
|
|
* The @set_state is the only mandatory operation. You can implement your
|
|
* pinctrl driver with its own @set_state. In this case, the other callbacks
|
|
* are not required. Otherwise, generic pinctrl framework is also available;
|
|
* use pinctrl_generic_set_state for @set_state, and implement other operations
|
|
* depending on your necessity.
|
|
*
|
|
* @get_pins_count: return number of selectable named pins available
|
|
* in this driver. (necessary to parse "pins" property in DTS)
|
|
* @get_pin_name: return the pin name of the pin selector,
|
|
* called by the core to figure out which pin it shall do
|
|
* operations to. (necessary to parse "pins" property in DTS)
|
|
* @get_groups_count: return number of selectable named groups available
|
|
* in this driver. (necessary to parse "groups" property in DTS)
|
|
* @get_group_name: return the group name of the group selector,
|
|
* called by the core to figure out which pin group it shall do
|
|
* operations to. (necessary to parse "groups" property in DTS)
|
|
* @get_functions_count: return number of selectable named functions available
|
|
* in this driver. (necessary for pin-muxing)
|
|
* @get_function_name: return the function name of the muxing selector,
|
|
* called by the core to figure out which mux setting it shall map a
|
|
* certain device to. (necessary for pin-muxing)
|
|
* @pinmux_set: enable a certain muxing function with a certain pin.
|
|
* The @func_selector selects a certain function whereas @pin_selector
|
|
* selects a certain pin to be used. On simple controllers one of them
|
|
* may be ignored. (necessary for pin-muxing against a single pin)
|
|
* @pinmux_group_set: enable a certain muxing function with a certain pin
|
|
* group. The @func_selector selects a certain function whereas
|
|
* @group_selector selects a certain set of pins to be used. On simple
|
|
* controllers one of them may be ignored.
|
|
* (necessary for pin-muxing against a pin group)
|
|
* @pinconf_num_params: number of driver-specific parameters to be parsed
|
|
* from device trees (necessary for pin-configuration)
|
|
* @pinconf_params: list of driver_specific parameters to be parsed from
|
|
* device trees (necessary for pin-configuration)
|
|
* @pinconf_set: configure an individual pin with a given parameter.
|
|
* (necessary for pin-configuration against a single pin)
|
|
* @pinconf_group_set: configure all pins in a group with a given parameter.
|
|
* (necessary for pin-configuration against a pin group)
|
|
* @set_state: do pinctrl operations specified by @config, a pseudo device
|
|
* pointing a config node. (necessary for pinctrl_full)
|
|
* @set_state_simple: do needed pinctrl operations for a peripherl @periph.
|
|
* (necessary for pinctrl_simple)
|
|
*/
|
|
struct pinctrl_ops {
|
|
int (*get_pins_count)(struct udevice *dev);
|
|
const char *(*get_pin_name)(struct udevice *dev, unsigned selector);
|
|
int (*get_groups_count)(struct udevice *dev);
|
|
const char *(*get_group_name)(struct udevice *dev, unsigned selector);
|
|
int (*get_functions_count)(struct udevice *dev);
|
|
const char *(*get_function_name)(struct udevice *dev,
|
|
unsigned selector);
|
|
int (*pinmux_set)(struct udevice *dev, unsigned pin_selector,
|
|
unsigned func_selector);
|
|
int (*pinmux_group_set)(struct udevice *dev, unsigned group_selector,
|
|
unsigned func_selector);
|
|
unsigned int pinconf_num_params;
|
|
const struct pinconf_param *pinconf_params;
|
|
int (*pinconf_set)(struct udevice *dev, unsigned pin_selector,
|
|
unsigned param, unsigned argument);
|
|
int (*pinconf_group_set)(struct udevice *dev, unsigned group_selector,
|
|
unsigned param, unsigned argument);
|
|
int (*set_state)(struct udevice *dev, struct udevice *config);
|
|
|
|
/* for pinctrl-simple */
|
|
int (*set_state_simple)(struct udevice *dev, struct udevice *periph);
|
|
/**
|
|
* request() - Request a particular pinctrl function
|
|
*
|
|
* This activates the selected function.
|
|
*
|
|
* @dev: Device to adjust (UCLASS_PINCTRL)
|
|
* @func: Function number (driver-specific)
|
|
* @return 0 if OK, -ve on error
|
|
*/
|
|
int (*request)(struct udevice *dev, int func, int flags);
|
|
|
|
/**
|
|
* get_periph_id() - get the peripheral ID for a device
|
|
*
|
|
* This generally looks at the peripheral's device tree node to work
|
|
* out the peripheral ID. The return value is normally interpreted as
|
|
* enum periph_id. so long as this is defined by the platform (which it
|
|
* should be).
|
|
*
|
|
* @dev: Pinctrl device to use for decoding
|
|
* @periph: Device to check
|
|
* @return peripheral ID of @periph, or -ENOENT on error
|
|
*/
|
|
int (*get_periph_id)(struct udevice *dev, struct udevice *periph);
|
|
|
|
/**
|
|
* get_gpio_mux() - get the mux value for a particular GPIO
|
|
*
|
|
* This allows the raw mux value for a GPIO to be obtained. It is
|
|
* useful for displaying the function being used by that GPIO, such
|
|
* as with the 'gpio' command. This function is internal to the GPIO
|
|
* subsystem and should not be used by generic code. Typically it is
|
|
* used by a GPIO driver with knowledge of the SoC pinctrl setup.
|
|
*
|
|
* @dev: Pinctrl device to use
|
|
* @banknum: GPIO bank number
|
|
* @index: GPIO index within the bank
|
|
* @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
|
|
*/
|
|
int (*get_gpio_mux)(struct udevice *dev, int banknum, int index);
|
|
};
|
|
|
|
#define pinctrl_get_ops(dev) ((struct pinctrl_ops *)(dev)->driver->ops)
|
|
|
|
/**
|
|
* Generic pin configuration paramters
|
|
*
|
|
* @PIN_CONFIG_BIAS_DISABLE: disable any pin bias on the pin, a
|
|
* transition from say pull-up to pull-down implies that you disable
|
|
* pull-up in the process, this setting disables all biasing.
|
|
* @PIN_CONFIG_BIAS_HIGH_IMPEDANCE: the pin will be set to a high impedance
|
|
* mode, also know as "third-state" (tristate) or "high-Z" or "floating".
|
|
* On output pins this effectively disconnects the pin, which is useful
|
|
* if for example some other pin is going to drive the signal connected
|
|
* to it for a while. Pins used for input are usually always high
|
|
* impedance.
|
|
* @PIN_CONFIG_BIAS_BUS_HOLD: the pin will be set to weakly latch so that it
|
|
* weakly drives the last value on a tristate bus, also known as a "bus
|
|
* holder", "bus keeper" or "repeater". This allows another device on the
|
|
* bus to change the value by driving the bus high or low and switching to
|
|
* tristate. The argument is ignored.
|
|
* @PIN_CONFIG_BIAS_PULL_UP: the pin will be pulled up (usually with high
|
|
* impedance to VDD). If the argument is != 0 pull-up is enabled,
|
|
* if it is 0, pull-up is total, i.e. the pin is connected to VDD.
|
|
* @PIN_CONFIG_BIAS_PULL_DOWN: the pin will be pulled down (usually with high
|
|
* impedance to GROUND). If the argument is != 0 pull-down is enabled,
|
|
* if it is 0, pull-down is total, i.e. the pin is connected to GROUND.
|
|
* @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
|
|
* on embedded knowledge of the controller hardware, like current mux
|
|
* function. The pull direction and possibly strength too will normally
|
|
* be decided completely inside the hardware block and not be readable
|
|
* from the kernel side.
|
|
* If the argument is != 0 pull up/down is enabled, if it is 0, the
|
|
* configuration is ignored. The proper way to disable it is to use
|
|
* @PIN_CONFIG_BIAS_DISABLE.
|
|
* @PIN_CONFIG_DRIVE_PUSH_PULL: the pin will be driven actively high and
|
|
* low, this is the most typical case and is typically achieved with two
|
|
* active transistors on the output. Setting this config will enable
|
|
* push-pull mode, the argument is ignored.
|
|
* @PIN_CONFIG_DRIVE_OPEN_DRAIN: the pin will be driven with open drain (open
|
|
* collector) which means it is usually wired with other output ports
|
|
* which are then pulled up with an external resistor. Setting this
|
|
* config will enable open drain mode, the argument is ignored.
|
|
* @PIN_CONFIG_DRIVE_OPEN_SOURCE: the pin will be driven with open source
|
|
* (open emitter). Setting this config will enable open source mode, the
|
|
* argument is ignored.
|
|
* @PIN_CONFIG_DRIVE_STRENGTH: the pin will sink or source at most the current
|
|
* passed as argument. The argument is in mA.
|
|
* @PIN_CONFIG_INPUT_ENABLE: enable the pin's input. Note that this does not
|
|
* affect the pin's ability to drive output. 1 enables input, 0 disables
|
|
* input.
|
|
* @PIN_CONFIG_INPUT_SCHMITT_ENABLE: control schmitt-trigger mode on the pin.
|
|
* If the argument != 0, schmitt-trigger mode is enabled. If it's 0,
|
|
* schmitt-trigger mode is disabled.
|
|
* @PIN_CONFIG_INPUT_SCHMITT: this will configure an input pin to run in
|
|
* schmitt-trigger mode. If the schmitt-trigger has adjustable hysteresis,
|
|
* the threshold value is given on a custom format as argument when
|
|
* setting pins to this mode.
|
|
* @PIN_CONFIG_INPUT_DEBOUNCE: this will configure the pin to debounce mode,
|
|
* which means it will wait for signals to settle when reading inputs. The
|
|
* argument gives the debounce time in usecs. Setting the
|
|
* argument to zero turns debouncing off.
|
|
* @PIN_CONFIG_POWER_SOURCE: if the pin can select between different power
|
|
* supplies, the argument to this parameter (on a custom format) tells
|
|
* the driver which alternative power source to use.
|
|
* @PIN_CONFIG_SLEW_RATE: if the pin can select slew rate, the argument to
|
|
* this parameter (on a custom format) tells the driver which alternative
|
|
* slew rate to use.
|
|
* @PIN_CONFIG_LOW_POWER_MODE: this will configure the pin for low power
|
|
* operation, if several modes of operation are supported these can be
|
|
* passed in the argument on a custom form, else just use argument 1
|
|
* to indicate low power mode, argument 0 turns low power mode off.
|
|
* @PIN_CONFIG_OUTPUT: this will configure the pin as an output. Use argument
|
|
* 1 to indicate high level, argument 0 to indicate low level. (Please
|
|
* see Documentation/pinctrl.txt, section "GPIO mode pitfalls" for a
|
|
* discussion around this parameter.)
|
|
* @PIN_CONFIG_END: this is the last enumerator for pin configurations, if
|
|
* you need to pass in custom configurations to the pin controller, use
|
|
* PIN_CONFIG_END+1 as the base offset.
|
|
*/
|
|
#define PIN_CONFIG_BIAS_DISABLE 0
|
|
#define PIN_CONFIG_BIAS_HIGH_IMPEDANCE 1
|
|
#define PIN_CONFIG_BIAS_BUS_HOLD 2
|
|
#define PIN_CONFIG_BIAS_PULL_UP 3
|
|
#define PIN_CONFIG_BIAS_PULL_DOWN 4
|
|
#define PIN_CONFIG_BIAS_PULL_PIN_DEFAULT 5
|
|
#define PIN_CONFIG_DRIVE_PUSH_PULL 6
|
|
#define PIN_CONFIG_DRIVE_OPEN_DRAIN 7
|
|
#define PIN_CONFIG_DRIVE_OPEN_SOURCE 8
|
|
#define PIN_CONFIG_DRIVE_STRENGTH 9
|
|
#define PIN_CONFIG_INPUT_ENABLE 10
|
|
#define PIN_CONFIG_INPUT_SCHMITT_ENABLE 11
|
|
#define PIN_CONFIG_INPUT_SCHMITT 12
|
|
#define PIN_CONFIG_INPUT_DEBOUNCE 13
|
|
#define PIN_CONFIG_POWER_SOURCE 14
|
|
#define PIN_CONFIG_SLEW_RATE 15
|
|
#define PIN_CONFIG_LOW_POWER_MODE 16
|
|
#define PIN_CONFIG_OUTPUT 17
|
|
#define PIN_CONFIG_END 0x7FFF
|
|
|
|
#if CONFIG_IS_ENABLED(PINCTRL_GENERIC)
|
|
/**
|
|
* pinctrl_generic_set_state() - generic set_state operation
|
|
* Parse the DT node of @config and its children and handle generic properties
|
|
* such as "pins", "groups", "functions", and pin configuration parameters.
|
|
*
|
|
* @pctldev: pinctrl device
|
|
* @config: config device (pseudo device), pointing a config node in DTS
|
|
* @return: 0 on success, or negative error code on failure
|
|
*/
|
|
int pinctrl_generic_set_state(struct udevice *pctldev, struct udevice *config);
|
|
#else
|
|
static inline int pinctrl_generic_set_state(struct udevice *pctldev,
|
|
struct udevice *config)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
#endif
|
|
|
|
#if CONFIG_IS_ENABLED(PINCTRL)
|
|
/**
|
|
* pinctrl_select_state() - set a device to a given state
|
|
*
|
|
* @dev: peripheral device
|
|
* @statename: state name, like "default"
|
|
* @return: 0 on success, or negative error code on failure
|
|
*/
|
|
int pinctrl_select_state(struct udevice *dev, const char *statename);
|
|
#else
|
|
static inline int pinctrl_select_state(struct udevice *dev,
|
|
const char *statename)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
#endif
|
|
|
|
/**
|
|
* pinctrl_request() - Request a particular pinctrl function
|
|
*
|
|
* @dev: Device to check (UCLASS_PINCTRL)
|
|
* @func: Function number (driver-specific)
|
|
* @flags: Flags (driver-specific)
|
|
* @return 0 if OK, -ve on error
|
|
*/
|
|
int pinctrl_request(struct udevice *dev, int func, int flags);
|
|
|
|
/**
|
|
* pinctrl_request_noflags() - Request a particular pinctrl function
|
|
*
|
|
* This is similar to pinctrl_request() but uses 0 for @flags.
|
|
*
|
|
* @dev: Device to check (UCLASS_PINCTRL)
|
|
* @func: Function number (driver-specific)
|
|
* @return 0 if OK, -ve on error
|
|
*/
|
|
int pinctrl_request_noflags(struct udevice *dev, int func);
|
|
|
|
/**
|
|
* pinctrl_get_periph_id() - get the peripheral ID for a device
|
|
*
|
|
* This generally looks at the peripheral's device tree node to work out the
|
|
* peripheral ID. The return value is normally interpreted as enum periph_id.
|
|
* so long as this is defined by the platform (which it should be).
|
|
*
|
|
* @dev: Pinctrl device to use for decoding
|
|
* @periph: Device to check
|
|
* @return peripheral ID of @periph, or -ENOENT on error
|
|
*/
|
|
int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph);
|
|
|
|
/**
|
|
* pinctrl_decode_pin_config() - decode pin configuration flags
|
|
*
|
|
* This decodes some of the PIN_CONFIG values into flags, with each value
|
|
* being (1 << pin_cfg). This does not support things with values like the
|
|
* slew rate.
|
|
*
|
|
* @blob: Device tree blob
|
|
* @node: Node containing the PIN_CONFIG values
|
|
* @return decoded flag value, or -ve on error
|
|
*/
|
|
int pinctrl_decode_pin_config(const void *blob, int node);
|
|
|
|
/**
|
|
* pinctrl_get_gpio_mux() - get the mux value for a particular GPIO
|
|
*
|
|
* This allows the raw mux value for a GPIO to be obtained. It is
|
|
* useful for displaying the function being used by that GPIO, such
|
|
* as with the 'gpio' command. This function is internal to the GPIO
|
|
* subsystem and should not be used by generic code. Typically it is
|
|
* used by a GPIO driver with knowledge of the SoC pinctrl setup.
|
|
*
|
|
* @dev: Pinctrl device to use
|
|
* @banknum: GPIO bank number
|
|
* @index: GPIO index within the bank
|
|
* @return mux value (SoC-specific, e.g. 0 for input, 1 for output)
|
|
*/
|
|
int pinctrl_get_gpio_mux(struct udevice *dev, int banknum, int index);
|
|
|
|
#endif /* __PINCTRL_H */
|