linux_dsm_epyc7002/drivers/pinctrl/core.h
Stephen Warren 652162d469 pinctrl: allow concurrent gpio and mux function ownership of pins
Per recent updates to Documentation/gpio.txt, gpiolib drivers should
inform pinctrl when a GPIO is requested. pinctrl then marks that pin as
in-use for that GPIO function.

When an SoC muxes pins in a group, it's quite possible for the group to
contain e.g. 6 pins, but only 4 of them actually be needed by the HW
module that's mux'd to them. In this case, the other 2 pins could be
used as GPIOs. However, pinctrl marks all the pins within the group as
in-use by the selected mux function. To allow the expected gpiolib
interaction, separate the concepts of pin ownership into two parts: One
for the mux function and one for GPIO usage. Finally, allow those two
ownerships to exist in parallel.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-03-12 22:43:09 +01:00

157 lines
4.8 KiB
C

/*
* Core private header for the pin control subsystem
*
* Copyright (C) 2011 ST-Ericsson SA
* Written on behalf of Linaro for ST-Ericsson
*
* Author: Linus Walleij <linus.walleij@linaro.org>
*
* License terms: GNU General Public License (GPL) version 2
*/
#include <linux/mutex.h>
#include <linux/radix-tree.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/machine.h>
struct pinctrl_gpio_range;
/**
* struct pinctrl_dev - pin control class device
* @node: node to include this pin controller in the global pin controller list
* @desc: the pin controller descriptor supplied when initializing this pin
* controller
* @pin_desc_tree: each pin descriptor for this pin controller is stored in
* this radix tree
* @gpio_ranges: a list of GPIO ranges that is handled by this pin controller,
* ranges are added to this list at runtime
* @dev: the device entry for this pin controller
* @owner: module providing the pin controller, used for refcounting
* @driver_data: driver data for drivers registering to the pin controller
* subsystem
* @p: result of pinctrl_get() for this device
* @device_root: debugfs root for this device
*/
struct pinctrl_dev {
struct list_head node;
struct pinctrl_desc *desc;
struct radix_tree_root pin_desc_tree;
struct list_head gpio_ranges;
struct device *dev;
struct module *owner;
void *driver_data;
struct pinctrl *p;
#ifdef CONFIG_DEBUG_FS
struct dentry *device_root;
#endif
};
/**
* struct pinctrl - per-device pin control state holder
* @node: global list node
* @dev: the device using this pin control handle
* @states: a list of states for this device
* @state: the current state
*/
struct pinctrl {
struct list_head node;
struct device *dev;
struct list_head states;
struct pinctrl_state *state;
};
/**
* struct pinctrl_state - a pinctrl state for a device
* @node: list not for struct pinctrl's @states field
* @name: the name of this state
* @settings: a list of settings for this state
*/
struct pinctrl_state {
struct list_head node;
const char *name;
struct list_head settings;
};
/**
* struct pinctrl_setting_mux - setting data for MAP_TYPE_MUX_GROUP
* @group: the group selector to program
* @func: the function selector to program
*/
struct pinctrl_setting_mux {
unsigned group;
unsigned func;
};
/**
* struct pinctrl_setting_configs - setting data for MAP_TYPE_CONFIGS_*
* @group_or_pin: the group selector or pin ID to program
* @configs: a pointer to an array of config parameters/values to program into
* hardware. Each individual pin controller defines the format and meaning
* of config parameters.
* @num_configs: the number of entries in array @configs
*/
struct pinctrl_setting_configs {
unsigned group_or_pin;
unsigned long *configs;
unsigned num_configs;
};
/**
* struct pinctrl_setting - an individual mux or config setting
* @node: list node for struct pinctrl_settings's @settings field
* @type: the type of setting
* @pctldev: pin control device handling to be programmed
* @data: Data specific to the setting type
*/
struct pinctrl_setting {
struct list_head node;
enum pinctrl_map_type type;
struct pinctrl_dev *pctldev;
union {
struct pinctrl_setting_mux mux;
struct pinctrl_setting_configs configs;
} data;
};
/**
* struct pin_desc - pin descriptor for each physical pin in the arch
* @pctldev: corresponding pin control device
* @name: a name for the pin, e.g. the name of the pin/pad/finger on a
* datasheet or such
* @dynamic_name: if the name of this pin was dynamically allocated
* @mux_usecount: If zero, the pin is not claimed, and @owner should be NULL.
* If non-zero, this pin is claimed by @owner. This field is an integer
* rather than a boolean, since pinctrl_get() might process multiple
* mapping table entries that refer to, and hence claim, the same group
* or pin, and each of these will increment the @usecount.
* @mux_owner: The name of device that called pinctrl_get().
* @mux_setting: The most recent selected mux setting for this pin, if any.
* @gpio_owner: If pinctrl_request_gpio() was called for this pin, this is
* the name of the GPIO that "owns" this pin.
*/
struct pin_desc {
struct pinctrl_dev *pctldev;
const char *name;
bool dynamic_name;
/* These fields only added when supporting pinmux drivers */
#ifdef CONFIG_PINMUX
unsigned mux_usecount;
const char *mux_owner;
const struct pinctrl_setting_mux *mux_setting;
const char *gpio_owner;
#endif
};
struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *dev_name);
int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name);
int pinctrl_get_group_selector(struct pinctrl_dev *pctldev,
const char *pin_group);
static inline struct pin_desc *pin_desc_get(struct pinctrl_dev *pctldev,
unsigned int pin)
{
return radix_tree_lookup(&pctldev->pin_desc_tree, pin);
}
extern struct mutex pinctrl_mutex;