229 lines
9.4 KiB
C
229 lines
9.4 KiB
C
/*
|
|
* Interface the generic pinconfig portions of the pinctrl subsystem
|
|
*
|
|
* Copyright (C) 2011 ST-Ericsson SA
|
|
* Written on behalf of Linaro for ST-Ericsson
|
|
* This interface is used in the core to keep track of pins.
|
|
*
|
|
* Author: Linus Walleij <linus.walleij@linaro.org>
|
|
*
|
|
* License terms: GNU General Public License (GPL) version 2
|
|
*/
|
|
#ifndef __LINUX_PINCTRL_PINCONF_GENERIC_H
|
|
#define __LINUX_PINCTRL_PINCONF_GENERIC_H
|
|
|
|
/**
|
|
* enum pin_config_param - possible pin configuration parameters
|
|
* @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_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_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_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_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_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_STRENGTH: the pin will sink or source at most the current
|
|
* passed as argument. The argument is in mA.
|
|
* @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_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: 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_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_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_ENABLE: this will enable the pin's output mode
|
|
* without driving a value there. For most platforms this reduces to
|
|
* enable the output buffers and then let the pin controller current
|
|
* configuration (eg. the currently selected mux function) drive values on
|
|
* the line. Use argument 1 to enable output mode, argument 0 to disable
|
|
* it.
|
|
* @PIN_CONFIG_OUTPUT: this will configure the pin as an output and drive a
|
|
* value on the line. Use argument 1 to indicate high level, argument 0 to
|
|
* indicate low level. (Please see Documentation/driver-api/pinctl.rst,
|
|
* section "GPIO mode pitfalls" for a discussion around this parameter.)
|
|
* @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_SLEEP_HARDWARE_STATE: indicate this is sleep related state.
|
|
* @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_SKEW_DELAY: if the pin has programmable skew rate (on inputs)
|
|
* or latch delay (on outputs) this parameter (in a custom format)
|
|
* specifies the clock skew or latch delay. It typically controls how
|
|
* many double inverters are put in front of the line.
|
|
* @PIN_CONFIG_PERSIST_STATE: retain pin state across sleep or controller reset
|
|
* @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.
|
|
* @PIN_CONFIG_MAX: this is the maximum configuration value that can be
|
|
* presented using the packed format.
|
|
*/
|
|
enum pin_config_param {
|
|
PIN_CONFIG_BIAS_BUS_HOLD,
|
|
PIN_CONFIG_BIAS_DISABLE,
|
|
PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
|
|
PIN_CONFIG_BIAS_PULL_DOWN,
|
|
PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
|
|
PIN_CONFIG_BIAS_PULL_UP,
|
|
PIN_CONFIG_DRIVE_OPEN_DRAIN,
|
|
PIN_CONFIG_DRIVE_OPEN_SOURCE,
|
|
PIN_CONFIG_DRIVE_PUSH_PULL,
|
|
PIN_CONFIG_DRIVE_STRENGTH,
|
|
PIN_CONFIG_INPUT_DEBOUNCE,
|
|
PIN_CONFIG_INPUT_ENABLE,
|
|
PIN_CONFIG_INPUT_SCHMITT,
|
|
PIN_CONFIG_INPUT_SCHMITT_ENABLE,
|
|
PIN_CONFIG_LOW_POWER_MODE,
|
|
PIN_CONFIG_OUTPUT_ENABLE,
|
|
PIN_CONFIG_OUTPUT,
|
|
PIN_CONFIG_POWER_SOURCE,
|
|
PIN_CONFIG_SLEEP_HARDWARE_STATE,
|
|
PIN_CONFIG_SLEW_RATE,
|
|
PIN_CONFIG_SKEW_DELAY,
|
|
PIN_CONFIG_PERSIST_STATE,
|
|
PIN_CONFIG_END = 0x7F,
|
|
PIN_CONFIG_MAX = 0xFF,
|
|
};
|
|
|
|
/*
|
|
* Helpful configuration macro to be used in tables etc.
|
|
*/
|
|
#define PIN_CONF_PACKED(p, a) ((a << 8) | ((unsigned long) p & 0xffUL))
|
|
|
|
/*
|
|
* The following inlines stuffs a configuration parameter and data value
|
|
* into and out of an unsigned long argument, as used by the generic pin config
|
|
* system. We put the parameter in the lower 8 bits and the argument in the
|
|
* upper 24 bits.
|
|
*/
|
|
|
|
static inline enum pin_config_param pinconf_to_config_param(unsigned long config)
|
|
{
|
|
return (enum pin_config_param) (config & 0xffUL);
|
|
}
|
|
|
|
static inline u32 pinconf_to_config_argument(unsigned long config)
|
|
{
|
|
return (u32) ((config >> 8) & 0xffffffUL);
|
|
}
|
|
|
|
static inline unsigned long pinconf_to_config_packed(enum pin_config_param param,
|
|
u32 argument)
|
|
{
|
|
return PIN_CONF_PACKED(param, argument);
|
|
}
|
|
|
|
#ifdef CONFIG_GENERIC_PINCONF
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
#define PCONFDUMP(a, b, c, d) { \
|
|
.param = a, .display = b, .format = c, .has_arg = d \
|
|
}
|
|
|
|
struct pin_config_item {
|
|
const enum pin_config_param param;
|
|
const char * const display;
|
|
const char * const format;
|
|
bool has_arg;
|
|
};
|
|
#endif /* CONFIG_DEBUG_FS */
|
|
|
|
#ifdef CONFIG_OF
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/pinctrl/machine.h>
|
|
struct pinctrl_dev;
|
|
struct pinctrl_map;
|
|
|
|
struct pinconf_generic_params {
|
|
const char * const property;
|
|
enum pin_config_param param;
|
|
u32 default_value;
|
|
};
|
|
|
|
int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
|
|
struct device_node *np, struct pinctrl_map **map,
|
|
unsigned *reserved_maps, unsigned *num_maps,
|
|
enum pinctrl_map_type type);
|
|
int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev,
|
|
struct device_node *np_config, struct pinctrl_map **map,
|
|
unsigned *num_maps, enum pinctrl_map_type type);
|
|
void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev,
|
|
struct pinctrl_map *map, unsigned num_maps);
|
|
|
|
static inline int pinconf_generic_dt_node_to_map_group(
|
|
struct pinctrl_dev *pctldev, struct device_node *np_config,
|
|
struct pinctrl_map **map, unsigned *num_maps)
|
|
{
|
|
return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps,
|
|
PIN_MAP_TYPE_CONFIGS_GROUP);
|
|
}
|
|
|
|
static inline int pinconf_generic_dt_node_to_map_pin(
|
|
struct pinctrl_dev *pctldev, struct device_node *np_config,
|
|
struct pinctrl_map **map, unsigned *num_maps)
|
|
{
|
|
return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps,
|
|
PIN_MAP_TYPE_CONFIGS_PIN);
|
|
}
|
|
|
|
static inline int pinconf_generic_dt_node_to_map_all(
|
|
struct pinctrl_dev *pctldev, struct device_node *np_config,
|
|
struct pinctrl_map **map, unsigned *num_maps)
|
|
{
|
|
/*
|
|
* passing the type as PIN_MAP_TYPE_INVALID causes the underlying parser
|
|
* to infer the map type from the DT properties used.
|
|
*/
|
|
return pinconf_generic_dt_node_to_map(pctldev, np_config, map, num_maps,
|
|
PIN_MAP_TYPE_INVALID);
|
|
}
|
|
#endif
|
|
|
|
#endif /* CONFIG_GENERIC_PINCONF */
|
|
|
|
#endif /* __LINUX_PINCTRL_PINCONF_GENERIC_H */
|