- 根目录:
- drivers
- pinctrl
- pinmux.c
/*
* Core driver for the pin muxing portions of the pin control subsystem
*
* Copyright (C) 2011 ST-Ericsson SA
* Written on behalf of Linaro for ST-Ericsson
* Based on bits of regulator core, gpio core and clk core
*
* Author: Linus Walleij <linus.walleij@linaro.org>
*
* License terms: GNU General Public License (GPL) version 2
*/
#define pr_fmt(fmt) "pinmux core: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/radix-tree.h>
#include <linux/err.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinmux.h>
#include "core.h"
/* List of pinmuxes */
static DEFINE_MUTEX(pinmux_list_mutex);
static LIST_HEAD(pinmux_list);
/* Global pinmux maps */
static struct pinmux_map *pinmux_maps;
static unsigned pinmux_maps_num;
/**
* struct pinmux_group - group list item for pinmux groups
* @node: pinmux group list node
* @group_selector: the group selector for this group
*/
struct pinmux_group {
struct list_head node;
unsigned group_selector;
};
/**
* struct pinmux - per-device pinmux state holder
* @node: global list node
* @dev: the device using this pinmux
* @usecount: the number of active users of this mux setting, used to keep
* track of nested use cases
* @pctldev: pin control device handling this pinmux
* @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
* @mutex: a lock for the pinmux state holder
*/
struct pinmux {
struct list_head node;
struct device *dev;
unsigned usecount;
struct pinctrl_dev *pctldev;
unsigned func_selector;
struct list_head groups;
struct mutex mutex;
};
/**
* struct pinmux_hog - a list item to stash mux hogs
* @node: pinmux hog list node
* @map: map entry responsible for this hogging
* @pmx: the pinmux hogged by this item
*/
struct pinmux_hog {
struct list_head node;
struct pinmux_map const *map;
struct pinmux *pmx;
};
/**
* pin_request() - request a single pin to be muxed in, typically for GPIO
* @pin: the pin number in the global pin space
* @function: a functional name to give to this pin, passed to the driver
* so it knows what function to mux in, e.g. the string "gpioNN"
* means that you want to mux in the pin for use as GPIO number NN
* @gpio_range: the range matching the GPIO pin if this is a request for a
* single GPIO pin
*/
static int pin_request(struct pinctrl_dev *pctldev,
int pin, const char *function,
struct pinctrl_gpio_range *gpio_range)
{
struct pin_desc *desc;
const struct pinmux_ops *ops = pctldev->desc->pmxops;
int status = -EINVAL;
dev_dbg(pctldev->dev, "request pin %d for %s\n", pin, function);
desc = pin_desc_get(pctldev, pin);
if (desc == NULL) {
dev_err(pctldev->dev,
"pin is not registered so it cannot be requested\n");
goto out;
}
if (!function) {
dev_err(pctldev->dev, "no function name given\n");
return -EINVAL;
}
spin_lock(&desc->lock);
if (desc->mux_function) {
spin_unlock(&desc->lock);
dev_err(pctldev->dev,
"pin already requested\n");
goto out;
}
desc->mux_function = function;
spin_unlock(&desc->lock);
/* Let each pin increase references to this module */
if (!try_module_get(pctldev->owner)) {
dev_err(pctldev->dev,
"could not increase module refcount for pin %d\n",
pin);
status = -EINVAL;
goto out_free_pin;
}
/*
* If there is no kind of request function for the pin we just assume
* we got it by default and proceed.
*/
if (gpio_range && ops->gpio_request_enable)
/* This requests and enables a single GPIO pin */
status = ops->gpio_request_enable(pctldev, gpio_range, pin);
else if (ops->request)
status = ops->request(pctldev, pin);
else
status = 0;
if (status)
dev_err(pctldev->dev, "->request on device %s failed for pin %d\n",
pctldev->desc->name, pin);
out_free_pin:
if (status) {
spin_lock(&desc->lock);
desc->mux_function = NULL;
spin_unlock(&desc->lock);
}
out:
if (status)
dev_err(pctldev->dev, "pin-%d (%s) status %d\n",
pin, function ? : "?", status);
return status;
}
/**
* pin_free() - release a single muxed in pin so something else can be muxed
* @pctldev: pin controller device handling this pin
* @pin: the pin to free
* @gpio_range: the range matching the GPIO pin if this is a request for a
* single GPIO pin
*
* This function returns a pointer to the function name in use. This is used
* for callers that dynamically allocate a function name so it can be freed
* once the pin is free. This is done for GPIO request functions.
*/
static const char *pin_free(struct pinctrl_dev *pctldev, int pin,
struct pinctrl_gpio_range *gpio_range)
{
const struct pinmux_ops *ops = pctldev->desc->pmxops;
struct pin_desc *desc;
const char *func;
desc = pin_desc_get(pctldev, pin);
if (desc == NULL) {
dev_err(pctldev->dev,
"pin is not registered so it cannot be freed\n");
return NULL;
}
/*
* If there is no kind of request function for the pin we just assume
* we got it by default and proceed.
*/
if (gpio_range && ops->gpio_disable_free)
ops->gpio_disable_free(pctldev, gpio_range, pin);
else if (ops->free)
ops->free(pctldev, pin);
spin_lock(&desc->lock);
func = desc->mux_function;
desc->mux_function = NULL;
spin_unlock(&desc->lock);
module_put(pctldev->owner);
return func;
}
/**
* pinmux_request_gpio() - request a single pin to be muxed in as GPIO
* @gpio: the GPIO pin number from the GPIO subsystem number space
*
* This function should *ONLY* be used from gpiolib-based GPIO drivers,
* as part of their gpio_request() semantics, platforms and individual drivers
* shall *NOT* request GPIO pins to be muxed in.
*/
int pinmux_request_gpio(unsigned gpio)
{
char gpiostr[16];
const char *function;
struct pinctrl_dev *pctldev;
struct pinctrl_gpio_range *range;
int ret;
int pin;
ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
if (ret)
return -EINVAL;
/* Convert to the pin controllers number space */
pin = gpio - range->base + range->pin_base;
/* Conjure some name stating what chip and pin this is taken by */
snprintf(gpiostr, 15, "%s:%d", range->name, gpio);
function = kstrdup(gpiostr, GFP_KERNEL);
if (!function)
return -EINVAL;
ret = pin_request(pctldev, pin, function, range);
if (ret < 0)
kfree(function);
return ret;
}
EXPORT_SYMBOL_GPL(pinmux_request_gpio);
/**
* pinmux_free_gpio() - free a single pin, currently used as GPIO
* @gpio: the GPIO pin number from the GPIO subsystem number space
*
* This function should *ONLY* be used from gpiolib-based GPIO drivers,
* as part of their gpio_free() semantics, platforms and individual drivers
* shall *NOT* request GPIO pins to be muxed out.
*/
void pinmux_free_gpio(unsigned gpio)
{
struct pinctrl_dev *pctldev;
struct pinctrl_gpio_range *range;
int ret;
int pin;
const char *func;
ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
if (ret)
return;
/* Convert to the pin controllers number space */
pin = gpio - range->base + range->pin_base;
func = pin_free(pctldev, pin, range);
kfree(func);
}
EXPORT_SYMBOL_GPL(pinmux_free_gpio);
static int pinmux_gpio_direction(unsigned gpio, bool input)
{
struct pinctrl_dev *pctldev;
struct pinctrl_gpio_range *range;
const struct pinmux_ops *ops;
int ret;
int pin;
ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
if (ret)
return ret;
ops = pctldev->desc->pmxops;
/* Convert to the pin controllers number space */
pin = gpio - range->base + range->pin_base;
if (ops->gpio_set_direction)
ret = ops->gpio_set_direction(pctldev, range, pin, input);
else
ret = 0;
return ret;
}
/**
* pinmux_gpio_direction_input() - request a GPIO pin to go into input mode
* @gpio: the GPIO pin number from the GPIO subsystem number space
*
* This function should *ONLY* be used from gpiolib-based GPIO drivers,
* as part of their gpio_direction_input() semantics, platforms and individual
* drivers shall *NOT* touch pinmux GPIO calls.
*/
int pinmux_gpio_direction_input(unsigned gpio)
{
return pinmux_gpio_direction(gpio, true);
}
EXPORT_SYMBOL_GPL(pinmux_gpio_direction_input);
/**
* pinmux_gpio_direction_output() - request a GPIO pin to go into output mode
* @gpio: the GPIO pin number from the GPIO subsystem number space
*
* This function should *ONLY* be used from gpiolib-based GPIO drivers,
* as part of their gpio_direction_output() semantics, platforms and individual
* drivers shall *NOT* touch pinmux GPIO calls.
*/
int pinmux_gpio_direction_output(unsigned gpio)
{
return pinmux_gpio_direction(gpio, false);
}
EXPORT_SYMBOL_GPL(pinmux_gpio_direction_output);
/**
* pinmux_register_mappings() - register a set of pinmux mappings
* @maps: the pinmux mappings table to register, this should be marked with
* __initdata so it can be discarded after boot, this function will
* perform a shallow copy for the mapping entries.
* @num_maps: the number of maps in the mapping table
*
* Only call this once during initialization of your machine, the function is
* tagged as __init and won't be callable after init has completed. The map
* passed into this function will be owned by the pinmux core and cannot be
* freed.
*/
int __init pinmux_register_mappings(struct pinmux_map const *maps,
unsigned num_maps)
{
void *tmp_maps;
int i;
pr_debug("add %d pinmux maps\n", num_maps);
/* First sanity check the new mapping */
for (i = 0; i < num_maps; i++) {
if (!maps[i].name) {
pr_err("failed to register map %d: no map name given\n",
i);
return -EINVAL;
}
if (!maps[i].ctrl_dev && !maps[i].ctrl_dev_name) {
pr_err("failed to register map %s (%d): no pin control device given\n",
maps[i].name, i);
return -EINVAL;
}
if (!maps[i].function) {
pr_err("failed to register map %s (%d): no function ID given\n",
maps[i].name, i);
return -EINVAL;
}
if (!maps[i].dev && !maps[i].dev_name)
pr_debug("add system map %s function %s with no device\n",
maps[i].name,
maps[i].function);
else
pr_debug("register map %s, function %s\n",
maps[i].name,
maps[i].function);
}
/*
* Make a copy of the map array - string pointers will end up in the
* kernel const section anyway so these do not need to be deep copied.
*/
if (!pinmux_maps_num) {
/* On first call, just copy them */
tmp_maps = kmemdup(maps,
sizeof(struct pinmux_map) * num_maps,
GFP_KERNEL);
if (!tmp_maps)
return -ENOMEM;
} else {
/* Subsequent calls, reallocate array to new size */
size_t oldsize = sizeof(struct pinmux_map) * pinmux_maps_num;
size_t newsize = sizeof(struct pinmux_map) * num_maps;
tmp_maps = krealloc(pinmux_maps, oldsize + newsize, GFP_KERNEL);
if (!tmp_maps)
return -ENOMEM;
memcpy((tmp_maps + oldsize), maps, newsize);
}
pinmux_maps = tmp_maps;
pinmux_maps_num += num_maps;
return 0;
}
/**
* acquire_pins() - acquire all the pins for a certain function on a pinmux
* @pctldev: the device to take the pins on
* @func_selector: the function selector to acquire the pins for
* @group_selector: the group selector containing the pins to acquire
*/
static int acquire_pins(struct pinctrl_dev *pctldev,
unsigned func_selector,
unsigned group_selector)
{
const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
const char *func = pmxops->get_function_name(pctldev,
func_selector);
const unsigned *pins;
unsigned num_pins;
int ret;
int i;
ret = pctlops->get_group_pins(pctldev, group_selector,
&pins, &num_pins);
if (ret)
return ret;
dev_dbg(pctldev->dev, "requesting the %u pins from group %u\n",
num_pins, group_selector);
/* Try to allocate all pins in this group, one by one */
for (i = 0; i < num_pins; i++) {
ret = pin_request(pctldev, pins[i], func, NULL);
if (ret) {
dev_err(pctldev->dev,
"could not get pin %d for function %s on device %s - conflicting mux mappings?\n",
pins[i], func ? : "(undefined)",
pinctrl_dev_get_name(pctldev));
/* On error release all taken pins */
i--; /* this pin just failed */
for (; i >= 0; i--)
pin_free(pctldev, pins[i], NULL);
return -ENODEV;
}
}
return 0;
}
/**
* release_pins() - release pins taken by earlier acquirement
* @pctldev: the device to free the pins on
* @group_selector: the group selector containing the pins to free
*/
static void release_pins(struct pinctrl_dev *pctldev,
unsigned group_selector)
{
const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
const unsigned *pins;
unsigned num_pins;
int ret;
int i;
ret = pctlops->get_group_pins(pctldev, group_selector,
&pins, &num_pins);
if (ret) {
dev_err(pctldev->dev, "could not get pins to release for group selector %d\n",
group_selector);
return;
}
for (i = 0; i < num_pins; i++)
pin_free(pctldev, pins[i], NULL);
}
/**
* pinmux_check_pin_group() - check function and pin group combo
* @pctldev: device to check the pin group vs function for
* @func_selector: the function selector to check the pin group for, we have
* already looked this up in the calling function
* @pin_group: the pin group to match to the function
*
* This function will check that the pinmux driver can supply the
* selected pin group for a certain function, returns the group selector if
* the group and function selector will work fine together, else returns
* negative
*/
static int pinmux_check_pin_group(struct pinctrl_dev *pctldev,
unsigned func_selector,
const char *pin_group)
{
const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
int ret;
/*
* If the driver does not support different pin groups for the
* functions, we only support group 0, and assume this exists.
*/
if (!pctlops || !pctlops->list_groups)
return 0;
/*
* Passing NULL (no specific group) will select the first and
* hopefully only group of pins available for this function.
*/
if (!pin_group) {
char const * const *groups;
unsigned num_groups;
ret = pmxops->get_function_groups(pctldev, func_selector,
&groups, &num_groups);
if (ret)
return ret;
if (num_groups < 1)
return -EINVAL;
ret = pinctrl_get_group_selector(pctldev, groups[0]);
if (ret < 0) {
dev_err(pctldev->dev,
"function %s wants group %s but the pin controller does not seem to have that group\n",
pmxops->get_function_name(pctldev, func_selector),
groups[0]);
return ret;
}
if (num_groups > 1)
dev_dbg(pctldev->dev,
"function %s support more than one group, default-selecting first group %s (%d)\n",
pmxops->get_function_name(pctldev, func_selector),
groups[0],
ret);
return ret;
}
dev_dbg(pctldev->dev,
"check if we have pin group %s on controller %s\n",
pin_group, pinctrl_dev_get_name(pctldev));
ret = pinctrl_get_group_selector(pctldev, pin_group);
if (ret < 0) {
dev_dbg(pctldev->dev,
"%s does not support pin group %s with function %s\n",
pinctrl_dev_get_name(pctldev),
pin_group,
pmxops->get_function_name(pctldev, func_selector));
}
return ret;
}
/**
* pinmux_search_function() - check pin control driver for a certain function
* @pctldev: device to check for function and position
* @map: function map containing the function and position to look for
* @func_selector: returns the applicable function selector if found
* @group_selector: returns the applicable group selector if found
*
* This will search the pinmux driver for an applicable
* function with a specific pin group, returns 0 if these can be mapped
* negative otherwise
*/
static int pinmux_search_function(struct pinctrl_dev *pctldev,
struct pinmux_map const *map,
unsigned *func_selector,
unsigned *group_selector)
{
const struct pinmux_ops *ops = pctldev->desc->pmxops;
unsigned selector = 0;
/* See if this pctldev has this function */
while (ops->list_functions(pctldev, selector) >= 0) {
const char *fname = ops->get_function_name(pctldev,
selector);
int ret;
if (!strcmp(map->function, fname)) {
/* Found the function, check pin group */
ret = pinmux_check_pin_group(pctldev, selector,
map->group);
if (ret < 0)
return ret;
/* This function and group selector can be used */
*func_selector = selector;
*group_selector = ret;
return 0;
}
selector++;
}
pr_err("%s does not support function %s\n",
pinctrl_dev_get_name(pctldev), map->function);
return -EINVAL;
}
/**
* pinmux_enable_muxmap() - enable a map entry for a certain pinmux
*/
static int pinmux_enable_muxmap(struct pinctrl_dev *pctldev,
struct pinmux *pmx,
struct device *dev,
const char *devname,
struct pinmux_map const *map)
{
unsigned func_selector;
unsigned group_selector;
struct pinmux_group *grp;
int ret;
/*
* Note that we're not locking the pinmux mutex here, because
* this is only called at pinmux initialization time when it
* has not been added to any list and thus is not reachable
* by anyone else.
*/
if (pmx->pctldev && pmx->pctldev != pctldev) {
dev_err(pctldev->dev,
"different pin control devices given for device %s, function %s\n",
devname, map->function);
return -EINVAL;
}
pmx->dev = dev;
pmx->pctldev = pctldev;
/* Now go into the driver and try to match a function and group */
ret = pinmux_search_function(pctldev, map, &func_selector,
&group_selector);
if (ret < 0)
return ret;
/*
* If the function selector is already set, it needs to be identical,
* we support several groups with one function but not several
* functions with one or several groups in the same pinmux.
*/
if (pmx->func_selector != UINT_MAX &&
pmx->func_selector != func_selector) {
dev_err(pctldev->dev,
"dual function defines in the map for device %s\n",
devname);
return -EINVAL;
}
pmx->func_selector = func_selector;
/* Now add this group selector, we may have many of them */
grp = kmalloc(sizeof(struct pinmux_group), GFP_KERNEL);
if (!grp)
return -ENOMEM;
grp->group_selector = group_selector;
ret = acquire_pins(pctldev, func_selector, group_selector);
if (ret) {
kfree(grp);
return ret;
}
list_add(&grp->node, &pmx->groups);
return 0;
}
static void pinmux_free_groups(struct pinmux *pmx)
{
struct list_head *node, *tmp;
list_for_each_safe(node, tmp, &pmx->groups) {
struct pinmux_group *grp =
list_entry(node, struct pinmux_group, node);
/* Release all pins taken by this group */
release_pins(pmx->pctldev, grp->group_selector);
list_del(node);
kfree(grp);
}
}
/**
* pinmux_get() - retrieves the pinmux for a certain device
* @dev: the device to get the pinmux for
* @name: an optional specific mux mapping name or NULL, the name is only
* needed if you want to have more than one mapping per device, or if you
* need an anonymous pinmux (not tied to any specific device)
*/
struct pinmux *pinmux_get(struct device *dev, const char *name)
{
struct pinmux_map const *map = NULL;
struct pinctrl_dev *pctldev = NULL;
const char *devname = NULL;
struct pinmux *pmx;
bool found_map;
unsigned num_maps = 0;
int ret = -ENODEV;
int i;
/* We must have dev or ID or both */
if (!dev && !name)
return ERR_PTR(-EINVAL);
if (dev)
devname = dev_name(dev);
pr_debug("get mux %s for device %s\n", name,
devname ? devname : "(none)");
/*
* create the state cookie holder struct pinmux for each
* mapping, this is what consumers will get when requesting
* a pinmux handle with pinmux_get()
*/
pmx = kzalloc(sizeof(struct pinmux), GFP_KERNEL);
if (pmx == NULL)
return ERR_PTR(-ENOMEM);
mutex_init(&pmx->mutex);
pmx->func_selector = UINT_MAX;
INIT_LIST_HEAD(&pmx->groups);
/* Iterate over the pinmux maps to locate the right ones */
for (i = 0; i < pinmux_maps_num; i++) {
map = &pinmux_maps[i];
found_map = false;
/*
* First, try to find the pctldev given in the map
*/
pctldev = get_pinctrl_dev_from_dev(map->ctrl_dev,
map->ctrl_dev_name);
if (!pctldev) {
const char *devname = NULL;
if (map->ctrl_dev)
devname = dev_name(map->ctrl_dev);
else if (map->ctrl_dev_name)
devname = map->ctrl_dev_name;
pr_warning("could not find a pinctrl device for pinmux function %s, fishy, they shall all have one\n",
map->function);
pr_warning("given pinctrl device name: %s",
devname ? devname : "UNDEFINED");
/* Continue to check the other mappings anyway... */
continue;
}
pr_debug("in map, found pctldev %s to handle function %s",
dev_name(pctldev->dev), map->function);
/*
* If we're looking for a specific named map, this must match,
* else we loop and look for the next.
*/
if (name != NULL) {
if (map->name == NULL)
continue;
if (strcmp(map->name, name))
continue;
}
/*
* This is for the case where no device name is given, we
* already know that the function name matches from above
* code.
*/
if (!map->dev_name && (name != NULL))
found_map = true;
/* If the mapping has a device set up it must match */
if (map->dev_name &&
(!devname || !strcmp(map->dev_name, devname)))
/* MATCH! */
found_map = true;
/* If this map is applicable, then apply it */
if (found_map) {
ret = pinmux_enable_muxmap(pctldev, pmx, dev,
devname, map);
if (ret) {
pinmux_free_groups(pmx);
kfree(pmx);
return ERR_PTR(ret);
}
num_maps++;
}
}
/* We should have atleast one map, right */
if (!num_maps) {
pr_err("could not find any mux maps for device %s, ID %s\n",
devname ? devname : "(anonymous)",
name ? name : "(undefined)");
kfree(pmx);
return ERR_PTR(-EINVAL);
}
pr_debug("found %u mux maps for device %s, UD %s\n",
num_maps,
devname ? devname : "(anonymous)",
name ? name : "(undefined)");
/* Add the pinmux to the global list */
mutex_lock(&pinmux_list_mutex);
list_add(&pmx->node, &pinmux_list);
mutex_unlock(&pinmux_list_mutex);
return pmx;
}
EXPORT_SYMBOL_GPL(pinmux_get);
/**
* pinmux_put() - release a previously claimed pinmux
* @pmx: a pinmux previously claimed by pinmux_get()
*/
void pinmux_put(struct pinmux *pmx)
{
if (pmx == NULL)
return;
mutex_lock(&pmx->mutex);
if (pmx->usecount)
pr_warn("releasing pinmux with active users!\n");
/* Free the groups and all acquired pins */
pinmux_free_groups(pmx);
mutex_unlock(&pmx->mutex);
/* Remove from list */
mutex_lock(&pinmux_list_mutex);
list_del(&pmx->node);
mutex_unlock(&pinmux_list_mutex);
kfree(pmx);
}
EXPORT_SYMBOL_GPL(pinmux_put);
/**
* pinmux_enable() - enable a certain pinmux setting
* @pmx: the pinmux to enable, previously claimed by pinmux_get()
*/
int pinmux_enable(struct pinmux *pmx)
{
int ret = 0;
if (pmx == NULL)
return -EINVAL;
mutex_lock(&pmx->mutex);
if (pmx->usecount++ == 0) {
struct pinctrl_dev *pctldev = pmx->pctldev;
const struct pinmux_ops *ops = pctldev->desc->pmxops;
struct pinmux_group *grp;
list_for_each_entry(grp, &pmx->groups, node) {
ret = ops->enable(pctldev, pmx->func_selector,
grp->group_selector);
if (ret) {
/*
* TODO: call disable() on all groups we called
* enable() on to this point?
*/
pmx->usecount--;
break;
}
}
}
mutex_unlock(&pmx->mutex);
return ret;
}
EXPORT_SYMBOL_GPL(pinmux_enable);
/**
* pinmux_disable() - disable a certain pinmux setting
* @pmx: the pinmux to disable, previously claimed by pinmux_get()
*/
void pinmux_disable(struct pinmux *pmx)
{
if (pmx == NULL)
return;
mutex_lock(&pmx->mutex);
if (--pmx->usecount == 0) {
struct pinctrl_dev *pctldev = pmx->pctldev;
const struct pinmux_ops *ops = pctldev->desc->pmxops;
struct pinmux_group *grp;
list_for_each_entry(grp, &pmx->groups, node) {
ops->disable(pctldev, pmx->func_selector,
grp->group_selector);
}
}
mutex_unlock(&pmx->mutex);
}
EXPORT_SYMBOL_GPL(pinmux_disable);
int pinmux_check_ops(struct pinctrl_dev *pctldev)
{
const struct pinmux_ops *ops = pctldev->desc->pmxops;
unsigned selector = 0;
/* Check that we implement required operations */
if (!ops->list_functions ||
!ops->get_function_name ||
!ops->get_function_groups ||
!ops->enable ||
!ops->disable)
return -EINVAL;
/* Check that all functions registered have names */
while (ops->list_functions(pctldev, selector) >= 0) {
const char *fname = ops->get_function_name(pctldev,
selector);
if (!fname) {
pr_err("pinmux ops has no name for function%u\n",
selector);
return -EINVAL;
}
selector++;
}
return 0;
}
/* Hog a single map entry and add to the hoglist */
static int pinmux_hog_map(struct pinctrl_dev *pctldev,
struct pinmux_map const *map)
{
struct pinmux_hog *hog;
struct pinmux *pmx;
int ret;
if (map->dev || map->dev_name) {
/*
* TODO: the day we have device tree support, we can
* traverse the device tree and hog to specific device nodes
* without any problems, so then we can hog pinmuxes for
* all devices that just want a static pin mux at this point.
*/
dev_err(pctldev->dev, "map %s wants to hog a non-system pinmux, this is not going to work\n",
map->name);
return -EINVAL;
}
hog = kzalloc(sizeof(struct pinmux_hog), GFP_KERNEL);
if (!hog)
return -ENOMEM;
pmx = pinmux_get(NULL, map->name);
if (IS_ERR(pmx)) {
kfree(hog);
dev_err(pctldev->dev,
"could not get the %s pinmux mapping for hogging\n",
map->name);
return PTR_ERR(pmx);
}
ret = pinmux_enable(pmx);
if (ret) {
pinmux_put(pmx);
kfree(hog);
dev_err(pctldev->dev,
"could not enable the %s pinmux mapping for hogging\n",
map->name);
return ret;
}
hog->map = map;
hog->pmx = pmx;
dev_info(pctldev->dev, "hogged map %s, function %s\n", map->name,
map->function);
mutex_lock(&pctldev->pinmux_hogs_lock);
list_add(&hog->node, &pctldev->pinmux_hogs);
mutex_unlock(&pctldev->pinmux_hogs_lock);
return 0;
}
/**
* pinmux_hog_maps() - hog specific map entries on controller device
* @pctldev: the pin control device to hog entries on
*
* When the pin controllers are registered, there may be some specific pinmux
* map entries that need to be hogged, i.e. get+enabled until the system shuts
* down.
*/
int pinmux_hog_maps(struct pinctrl_dev *pctldev)
{
struct device *dev = pctldev->dev;
const char *devname = dev_name(dev);
int ret;
int i;
INIT_LIST_HEAD(&pctldev->pinmux_hogs);
mutex_init(&pctldev->pinmux_hogs_lock);
for (i = 0; i < pinmux_maps_num; i++) {
struct pinmux_map const *map = &pinmux_maps[i];
if (!map->hog_on_boot)
continue;
if ((map->ctrl_dev == dev) ||
(map->ctrl_dev_name &&
!strcmp(map->ctrl_dev_name, devname))) {
/* OK time to hog! */
ret = pinmux_hog_map(pctldev, map);
if (ret)
return ret;
}
}
return 0;
}
/**
* pinmux_unhog_maps() - unhog specific map entries on controller device
* @pctldev: the pin control device to unhog entries on
*/
void pinmux_unhog_maps(struct pinctrl_dev *pctldev)
{
struct list_head *node, *tmp;
mutex_lock(&pctldev->pinmux_hogs_lock);
list_for_each_safe(node, tmp, &pctldev->pinmux_hogs) {
struct pinmux_hog *hog =
list_entry(node, struct pinmux_hog, node);
pinmux_disable(hog->pmx);
pinmux_put(hog->pmx);
list_del(node);
kfree(hog);
}
mutex_unlock(&pctldev->pinmux_hogs_lock);
}
#ifdef CONFIG_DEBUG_FS
/* Called from pincontrol core */
static int pinmux_functions_show(struct seq_file *s, void *what)
{
struct pinctrl_dev *pctldev = s->private;
const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
unsigned func_selector = 0;
while (pmxops->list_functions(pctldev, func_selector) >= 0) {
const char *func = pmxops->get_function_name(pctldev,
func_selector);
const char * const *groups;
unsigned num_groups;
int ret;
int i;
ret = pmxops->get_function_groups(pctldev, func_selector,
&groups, &num_groups);
if (ret)
seq_printf(s, "function %s: COULD NOT GET GROUPS\n",
func);
seq_printf(s, "function: %s, groups = [ ", func);
for (i = 0; i < num_groups; i++)
seq_printf(s, "%s ", groups[i]);
seq_puts(s, "]\n");
func_selector++;
}
return 0;
}
static int pinmux_pins_show(struct seq_file *s, void *what)
{
struct pinctrl_dev *pctldev = s->private;
unsigned i, pin;
seq_puts(s, "Pinmux settings per pin\n");
seq_puts(s, "Format: pin (name): pinmuxfunction\n");
/* The pin number can be retrived from the pin controller descriptor */
for (i = 0; i < pctldev->desc->npins; i++) {
struct pin_desc *desc;
pin = pctldev->desc->pins[i].number;
desc = pin_desc_get(pctldev, pin);
/* Skip if we cannot search the pin */
if (desc == NULL)
continue;
seq_printf(s, "pin %d (%s): %s\n", pin,
desc->name ? desc->name : "unnamed",
desc->mux_function ? desc->mux_function
: "UNCLAIMED");
}
return 0;
}
static int pinmux_hogs_show(struct seq_file *s, void *what)
{
struct pinctrl_dev *pctldev = s->private;
struct pinmux_hog *hog;
seq_puts(s, "Pinmux map hogs held by device\n");
list_for_each_entry(hog, &pctldev->pinmux_hogs, node)
seq_printf(s, "%s\n", hog->map->name);
return 0;
}
static int pinmux_show(struct seq_file *s, void *what)
{
struct pinmux *pmx;
seq_puts(s, "Requested pinmuxes and their maps:\n");
list_for_each_entry(pmx, &pinmux_list, node) {
struct pinctrl_dev *pctldev = pmx->pctldev;
const struct pinmux_ops *pmxops;
const struct pinctrl_ops *pctlops;
struct pinmux_group *grp;
if (!pctldev) {
seq_puts(s, "NO PIN CONTROLLER DEVICE\n");
continue;
}
pmxops = pctldev->desc->pmxops;
pctlops = pctldev->desc->pctlops;
seq_printf(s, "device: %s function: %s (%u),",
pinctrl_dev_get_name(pmx->pctldev),
pmxops->get_function_name(pctldev,
pmx->func_selector),
pmx->func_selector);
seq_printf(s, " groups: [");
list_for_each_entry(grp, &pmx->groups, node) {
seq_printf(s, " %s (%u)",
pctlops->get_group_name(pctldev,
grp->group_selector),
grp->group_selector);
}
seq_printf(s, " ]");
seq_printf(s, " users: %u map-> %s\n",
pmx->usecount,
pmx->dev ? dev_name(pmx->dev) : "(system)");
}
return 0;
}
static int pinmux_maps_show(struct seq_file *s, void *what)
{
int i;
seq_puts(s, "Pinmux maps:\n");
for (i = 0; i < pinmux_maps_num; i++) {
struct pinmux_map const *map = &pinmux_maps[i];
seq_printf(s, "%s:\n", map->name);
if (map->dev || map->dev_name)
seq_printf(s, " device: %s\n",
map->dev ? dev_name(map->dev) :
map->dev_name);
else
seq_printf(s, " SYSTEM MUX\n");
seq_printf(s, " controlling device %s\n",
map->ctrl_dev ? dev_name(map->ctrl_dev) :
map->ctrl_dev_name);
seq_printf(s, " function: %s\n", map->function);
seq_printf(s, " group: %s\n", map->group ? map->group :
"(default)");
}
return 0;
}
static int pinmux_functions_open(struct inode *inode, struct file *file)
{
return single_open(file, pinmux_functions_show, inode->i_private);
}
static int pinmux_pins_open(struct inode *inode, struct file *file)
{
return single_open(file, pinmux_pins_show, inode->i_private);
}
static int pinmux_hogs_open(struct inode *inode, struct file *file)
{
return single_open(file, pinmux_hogs_show, inode->i_private);
}
static int pinmux_open(struct inode *inode, struct file *file)
{
return single_open(file, pinmux_show, NULL);
}
static int pinmux_maps_open(struct inode *inode, struct file *file)
{
return single_open(file, pinmux_maps_show, NULL);
}
static const struct file_operations pinmux_functions_ops = {
.open = pinmux_functions_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations pinmux_pins_ops = {
.open = pinmux_pins_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations pinmux_hogs_ops = {
.open = pinmux_hogs_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations pinmux_ops = {
.open = pinmux_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations pinmux_maps_ops = {
.open = pinmux_maps_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
void pinmux_init_device_debugfs(struct dentry *devroot,
struct pinctrl_dev *pctldev)
{
debugfs_create_file("pinmux-functions", S_IFREG | S_IRUGO,
devroot, pctldev, &pinmux_functions_ops);
debugfs_create_file("pinmux-pins", S_IFREG | S_IRUGO,
devroot, pctldev, &pinmux_pins_ops);
debugfs_create_file("pinmux-hogs", S_IFREG | S_IRUGO,
devroot, pctldev, &pinmux_hogs_ops);
}
void pinmux_init_debugfs(struct dentry *subsys_root)
{
debugfs_create_file("pinmuxes", S_IFREG | S_IRUGO,
subsys_root, NULL, &pinmux_ops);
debugfs_create_file("pinmux-maps", S_IFREG | S_IRUGO,
subsys_root, NULL, &pinmux_maps_ops);
}
#endif /* CONFIG_DEBUG_FS */