summaryrefslogtreecommitdiff
path: root/include/linux/pinctrl/pinconf-generic.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/pinctrl/pinconf-generic.h')
-rw-r--r--include/linux/pinctrl/pinconf-generic.h210
1 files changed, 210 insertions, 0 deletions
diff --git a/include/linux/pinctrl/pinconf-generic.h b/include/linux/pinctrl/pinconf-generic.h
new file mode 100644
index 000000000..fe65962b2
--- /dev/null
+++ b/include/linux/pinctrl/pinconf-generic.h
@@ -0,0 +1,210 @@
+/*
+ * 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
+
+/*
+ * You shouldn't even be able to compile with these enums etc unless you're
+ * using generic pin config. That is why this is defined out.
+ */
+#ifdef CONFIG_GENERIC_PINCONF
+
+/**
+ * enum pin_config_param - possible pin configuration parameters
+ * @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.
+ */
+enum pin_config_param {
+ PIN_CONFIG_BIAS_DISABLE,
+ PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
+ PIN_CONFIG_BIAS_BUS_HOLD,
+ PIN_CONFIG_BIAS_PULL_UP,
+ PIN_CONFIG_BIAS_PULL_DOWN,
+ PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
+ PIN_CONFIG_DRIVE_PUSH_PULL,
+ PIN_CONFIG_DRIVE_OPEN_DRAIN,
+ PIN_CONFIG_DRIVE_OPEN_SOURCE,
+ PIN_CONFIG_DRIVE_STRENGTH,
+ PIN_CONFIG_INPUT_ENABLE,
+ PIN_CONFIG_INPUT_SCHMITT_ENABLE,
+ PIN_CONFIG_INPUT_SCHMITT,
+ PIN_CONFIG_INPUT_DEBOUNCE,
+ PIN_CONFIG_POWER_SOURCE,
+ PIN_CONFIG_SLEW_RATE,
+ PIN_CONFIG_LOW_POWER_MODE,
+ PIN_CONFIG_OUTPUT,
+ PIN_CONFIG_END = 0x7FFF,
+};
+
+#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 */
+
+/*
+ * Helpful configuration macro to be used in tables etc.
+ */
+#define PIN_CONF_PACKED(p, a) ((a << 16) | ((unsigned long) p & 0xffffUL))
+
+/*
+ * 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 16 bits and the argument in the
+ * upper 16 bits.
+ */
+
+static inline enum pin_config_param pinconf_to_config_param(unsigned long config)
+{
+ return (enum pin_config_param) (config & 0xffffUL);
+}
+
+static inline u16 pinconf_to_config_argument(unsigned long config)
+{
+ return (enum pin_config_param) ((config >> 16) & 0xffffUL);
+}
+
+static inline unsigned long pinconf_to_config_packed(enum pin_config_param param,
+ u16 argument)
+{
+ return PIN_CONF_PACKED(param, argument);
+}
+
+#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);
+
+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 */