linux/drivers/pinctrl/core.h
Stephen Warren 5d2eaf8090 pinctrl: Don't copy function name when requesting a pin
Instead, store a pointer to the currently assigned function.

This allows us to delete the mux_requested variable from pin_desc; a pin
is requested if its currently assigned function is non-NULL.

When a pin is requested as a GPIO rather than a regular function, the
assigned function name is dynamically constructed. In this case, we have
to kstrdup() the dynamically constructed name, so that mux_function doesn't
pointed at stack data. This requires pin_free to be told whether to free
the mux_function pointer or not.

This removes the hard-coded maximum function name length.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-10-20 11:50:07 +02:00

71 lines
2.4 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
*/
/**
* 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
* @pinmux_hogs_lock: lock for the pinmux hog list
* @pinmux_hogs: list of pinmux maps hogged by 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;
#ifdef CONFIG_PINMUX
struct mutex pinmux_hogs_lock;
struct list_head pinmux_hogs;
#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
* @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;
spinlock_t lock;
/* These fields only added when supporting pinmux drivers */
#ifdef CONFIG_PINMUX
const char *mux_function;
#endif
};
struct pinctrl_dev *get_pinctrl_dev_from_dev(struct device *dev,
const char *dev_name);
struct pin_desc *pin_desc_get(struct pinctrl_dev *pctldev, int pin);
int pinctrl_get_device_gpio_range(unsigned gpio,
struct pinctrl_dev **outdev,
struct pinctrl_gpio_range **outrange);