// SPDX-License-Identifier: GPL-2.0-only
/*
* Device tree integration for the pin control subsystem
*
* Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
*/
#include <linux/device.h>
#include <linux/of.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/slab.h>
#include "core.h"
#include "devicetree.h"
/**
* struct pinctrl_dt_map - mapping table chunk parsed from device tree
* @node: list node for struct pinctrl's @dt_maps field
* @pctldev: the pin controller that allocated this struct, and will free it
* @maps: the mapping table entries
*/
struct pinctrl_dt_map {
struct list_head node;
struct pinctrl_dev *pctldev;
struct pinctrl_map *map;
unsigned num_maps;
};
static void dt_free_map(struct pinctrl_dev *pctldev,
struct pinctrl_map *map, unsigned num_maps)
{
if (pctldev) {
const struct pinctrl_ops *ops = pctldev->desc->pctlops;
if (ops->dt_free_map)
ops->dt_free_map(pctldev, map, num_maps);
} else {
/* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
kfree(map);
}
}
void pinctrl_dt_free_maps(struct pinctrl *p)
{
struct pinctrl_dt_map *dt_map, *n1;
list_for_each_entry_safe(dt_map, n1, &p->dt_maps, node) {
pinctrl_unregister_map(dt_map->map);
list_del(&dt_map->node);
dt_free_map(dt_map->pctldev, dt_map->map,
dt_map->num_maps);
kfree(dt_map);
}
of_node_put(p->dev->of_node);
}
static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,
struct pinctrl_dev *pctldev,
struct pinctrl_map *map, unsigned num_maps)
{
int i;
struct pinctrl_dt_map *dt_map;
/* Initialize common mapping table entry fields */
for (i = 0; i < num_maps; i++) {
map[i].dev_name = dev_name(p->dev);
map[i].name = statename;
if (pctldev)
map[i].ctrl_dev_name = dev_name(pctldev->dev);
}
/* Remember the converted mapping table entries */
dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);
if (!dt_map) {
dt_free_map(pctldev, map, num_maps);
return -ENOMEM;
}
dt_map->pctldev = pctldev;
dt_map->map = map;
dt_map->num_maps = num_maps;
list_add_tail(&dt_map->node, &p->dt_maps);
return pinctrl_register_map(map, num_maps, false);
}
struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
{
return get_pinctrl_dev_from_of_node(np);
}
static int dt_to_map_one_config(struct pinctrl *p,
struct pinctrl_dev *hog_pctldev,
const char *statename,
struct device_node *np_config)
{
struct pinctrl_dev *pctldev = NULL;
struct device_node *np_pctldev;
const struct pinctrl_ops *ops;
int ret;
struct pinctrl_map *map;
unsigned num_maps;
bool allow_default = false;
/* Find the pin controller containing np_config */
np_pctldev = of_node_get(np_config);
for (;;) {
if (!allow_default)
allow_default = of_property_read_bool(np_pctldev,
"pinctrl-use-default");
np_pctldev = of_get_next_parent(np_pctldev);
if (!np_pctldev || of_node_is_root(np_pctldev)) {
of_node_put(np_pctldev);
/* keep deferring if modules are enabled unless we've timed out */
if (IS_ENABLED(CONFIG_MODULES) && !allow_default)
return driver_deferred_probe_check_state_continue(p->dev);
return driver_deferred_probe_check_state(p->dev);
}
/* If we're creating a hog we can use the passed pctldev */
if (hog_pctldev && (np_pctldev == p->dev->of_node)) {
pctldev = hog_pctldev;
break;
}
pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
if (pctldev)
break;
/* Do not defer probing of hogs (circular loop) */
if (np_pctldev == p->dev->of_node) {
of_node_put(np_pctldev);
return -ENODEV;
}
}
of_node_put(np_pctldev);
/*
* Call pinctrl driver to parse device tree node, and
* generate mapping table entries
*/
ops = pctldev->desc->pctlops;
if (!ops->dt_node_to_map) {
dev_err(p->dev, "pctldev %s doesn't support DT\n",
dev_name(pctldev->dev));
return -ENODEV;
}
ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
if (ret < 0)
return ret;
/* Stash the mapping table chunk away for later use */
return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
}
static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
{
struct pinctrl_map *map;
map = kzalloc(sizeof(*map), GFP_KERNEL);
if (!map)
return -ENOMEM;
/* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
map->type = PIN_MAP_TYPE_DUMMY_STATE;
return dt_remember_or_free_map(p, statename, NULL, map, 1);
}
bool pinctrl_dt_has_hogs(struct pinctrl_dev *pctldev)
{
struct device_node *np;
struct property *prop;
int size;
np = pctldev->dev->of_node;
if (!np)
return false;
prop = of_find_property(np, "pinctrl-0", &size);
return prop ? true : false;
}
int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
{
struct device_node *np = p->dev->of_node;
int state, ret;
char *propname;
struct property *prop;
const char *statename;
const __be32 *list;
int size, config;
phandle phandle;
struct device_node *np_config;
/* CONFIG_OF enabled, p->dev not instantiated from DT */
if (!np) {
if (of_have_populated_dt())
dev_dbg(p->dev,
"no of_node; not parsing pinctrl DT\n");
return 0;
}
/* We may store pointers to property names within the node */
of_node_get(np);
/* For each defined state ID */
for (state = 0; ; state++) {
/* Retrieve the pinctrl-* property */
propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
prop = of_find_property(np, propname, &size);
kfree(propname);
if (!prop) {
if (state == 0) {
of_node_put(np);
return -ENODEV;
}
break;
}
list = prop->value;
size /= sizeof(*list);
/* Determine whether pinctrl-names property names the state */
ret = of_property_read_string_index(np, "pinctrl-names",
state, &statename);
/*
* If not, statename is just the integer state ID. But rather
* than dynamically allocate it and have to free it later,
* just point part way into the property name for the string.
*/
if (ret < 0) {
/* strlen("pinctrl-") == 8 */
statename = prop->name + 8;
}
/* For every referenced pin configuration node in it */
for (config = 0; config < size; config++) {
phandle = be32_to_cpup(list++);
/* Look up the pin configuration node */
np_config = of_find_node_by_phandle(phandle);
if (!np_config) {
dev_err(p->dev,
"prop %s index %i invalid phandle\n",
prop->name, config);
ret = -EINVAL;
goto err;
}
/* Parse the node */
ret = dt_to_map_one_config(p, pctldev, statename,
np_config);
of_node_put(np_config);
if (ret < 0)
goto err;
}
/* No entries in DT? Generate a dummy state table entry */
if (!size) {
ret = dt_remember_dummy_state(p, statename);
if (ret < 0)
goto err;
}
}
return 0;
err:
pinctrl_dt_free_maps(p);
return ret;
}
/*
* For pinctrl binding, typically #pinctrl-cells is for the pin controller
* device, so either parent or grandparent. See pinctrl-bindings.txt.
*/
static int pinctrl_find_cells_size(const struct device_node *np)
{
const char *cells_name = "#pinctrl-cells";
int cells_size, error;
error = of_property_read_u32(np->parent, cells_name, &cells_size);
if (error) {
error = of_property_read_u32(np->parent->parent,
cells_name, &cells_size);
if (error)
return -ENOENT;
}
return cells_size;
}
/**
* pinctrl_get_list_and_count - Gets the list and it's cell size and number
* @np: pointer to device node with the property
* @list_name: property that contains the list
* @list: pointer for the list found
* @cells_size: pointer for the cell size found
* @nr_elements: pointer for the number of elements found
*
* Typically np is a single pinctrl entry containing the list.
*/
static int pinctrl_get_list_and_count(const struct device_node *np,
const char *list_name,
const __be32 **list,
int *cells_size,
int *nr_elements)
{
int size;
*cells_size = 0;
*nr_elements = 0;
*list = of_get_property(np, list_name, &size);
if (!*list)
return -ENOENT;
*cells_size = pinctrl_find_cells_size(np);
if (*cells_size < 0)
return -ENOENT;
/* First element is always the index within the pinctrl device */
*nr_elements = (size / sizeof(**list)) / (*cells_size + 1);
return 0;
}
/**
* pinctrl_count_index_with_args - Count number of elements in a pinctrl entry
* @np: pointer to device node with the property
* @list_name: property that contains the list
*
* Counts the number of elements in a pinctrl array consisting of an index
* within the controller and a number of u32 entries specified for each
* entry. Note that device_node is always for the parent pin controller device.
*/
int pinctrl_count_index_with_args(const struct device_node *np,
const char *list_name)
{
const __be32 *list;
int size, nr_cells, error;
error = pinctrl_get_list_and_count(np, list_name, &list,
&nr_cells, &size);
if (error)
return error;
return size;
}
EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);
/**
* pinctrl_copy_args - Populates of_phandle_args based on index
* @np: pointer to device node with the property
* @list: pointer to a list with the elements
* @index: entry within the list of elements
* @nr_cells: number of cells in the list
* @nr_elem: number of elements for each entry in the list
* @out_args: returned values
*
* Populates the of_phandle_args based on the index in the list.
*/
static int pinctrl_copy_args(const struct device_node *np,
const __be32 *list,
int index, int nr_cells, int nr_elem,
struct of_phandle_args *out_args)
{
int i;
memset(out_args, 0, sizeof(*out_args));
out_args->np = (struct device_node *)np;
out_args->args_count = nr_cells + 1;
if (index >= nr_elem)
return -EINVAL;
list += index * (nr_cells + 1);
for (i = 0; i < nr_cells + 1; i++)
out_args->args[i] = be32_to_cpup(list++);
return 0;
}
/**
* pinctrl_parse_index_with_args - Find a node pointed by index in a list
* @np: pointer to device node with the property
* @list_name: property that contains the list
* @index: index within the list
* @out_arts: entries in the list pointed by index
*
* Finds the selected element in a pinctrl array consisting of an index
* within the controller and a number of u32 entries specified for each
* entry. Note that device_node is always for the parent pin controller device.
*/
int pinctrl_parse_index_with_args(const struct device_node *np,
const char *list_name, int index,
struct of_phandle_args *out_args)
{
const __be32 *list;
int nr_elem, nr_cells, error;
error = pinctrl_get_list_and_count(np, list_name, &list,
&nr_cells, &nr_elem);
if (error || !nr_cells)
return error;
error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,
out_args);
if (error)
return error;
return 0;
}
EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);
