alistair23-linux/drivers/pinctrl/core.h
Stephen Warren 3cc70ed32c pinctrl: record a pin owner, not mux function, when requesting pins
When pins are requested/acquired/got, some device becomes the owner of
their mux setting. At this point, it isn't certain which mux function
will be selected for the pin, since this may vary between each of the
device's states in the pinctrl mapping table. As such, we should record
the owning device, not what we think the initial mux setting will be,
when requesting pins.

This doesn't make a lot of difference right now since pinctrl_get gets
only one single device/state combination, but this will make a difference
when pinctrl_get gets all states, and pinctrl_select_state can switch
between states.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-02-22 17:59:35 +01:00

106 lines
3.5 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/pinctrl/pinconf.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
* @pin_desc_tree_lock: lock for the descriptor tree
* @gpio_ranges: a list of GPIO ranges that is handled by this pin controller,
* ranges are added to this list at runtime
* @gpio_ranges_lock: lock for the GPIO ranges list
* @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
* @pinctrl_hogs_lock: lock for the pin control hog list
* @pinctrl_hogs: list of pin control maps hogged by 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;
spinlock_t pin_desc_tree_lock;
struct list_head gpio_ranges;
struct mutex gpio_ranges_lock;
struct device *dev;
struct module *owner;
void *driver_data;
struct mutex pinctrl_hogs_lock;
struct list_head pinctrl_hogs;
#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
* @usecount: the number of active users of this pin controller setting, used
* to keep track of nested use cases
* @pctldev: pin control device handling this pin control handle
* @mutex: a lock for the pin control state holder
* @func_selector: the function selector for the pinmux device handling
* this pinmux
* @groups: the group selectors for the pinmux device and
* selector combination handling this pinmux, this is a list that
* will be traversed on all pinmux operations such as
* get/put/enable/disable
*/
struct pinctrl {
struct list_head node;
struct device *dev;
unsigned usecount;
struct pinctrl_dev *pctldev;
struct mutex mutex;
#ifdef CONFIG_PINMUX
unsigned func_selector;
struct list_head groups;
#endif
};
/**
* 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
* @lock: a lock to protect the descriptor structure
* @mux_requested: whether the pin is already requested by pinmux or not
* @mux_function: a named muxing function for the pin that will be passed to
* subdrivers and shown in debugfs etc
*/
struct pin_desc {
struct pinctrl_dev *pctldev;
const char *name;
bool dynamic_name;
spinlock_t lock;
/* These fields only added when supporting pinmux drivers */
#ifdef CONFIG_PINMUX
const char *owner;
#endif
};
struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *dev_name);
struct pin_desc *pin_desc_get(struct pinctrl_dev *pctldev, unsigned int pin);
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);