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-rw-r--r--drivers/pinctrl/devicetree.c427
1 files changed, 427 insertions, 0 deletions
diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c
new file mode 100644
index 000000000..6e0a40962
--- /dev/null
+++ b/drivers/pinctrl/devicetree.c
@@ -0,0 +1,427 @@
+// 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
+ * @map: the mapping table entries
+ * @num_maps: number of 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)
+{
+ int i;
+
+ for (i = 0; i < num_maps; ++i) {
+ kfree_const(map[i].dev_name);
+ map[i].dev_name = NULL;
+ }
+
+ 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_mappings(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++) {
+ const char *devname;
+
+ devname = kstrdup_const(dev_name(p->dev), GFP_KERNEL);
+ if (!devname)
+ goto err_free_map;
+
+ map[i].dev_name = devname;
+ 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)
+ goto err_free_map;
+
+ 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_mappings(map, num_maps);
+
+err_free_map:
+ dt_free_map(pctldev, map, num_maps);
+ return -ENOMEM;
+}
+
+struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
+{
+ return get_pinctrl_dev_from_of_node(np);
+}
+EXPORT_SYMBOL_GPL(of_pinctrl_get);
+
+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);
+ ret = -ENODEV;
+ /* keep deferring if modules are enabled */
+ if (IS_ENABLED(CONFIG_MODULES) && !allow_default && ret < 0)
+ ret = -EPROBE_DEFER;
+ return ret;
+ }
+ /* 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;
+ else if (num_maps == 0) {
+ /*
+ * If we have no valid maps (maybe caused by empty pinctrl node
+ * or typing error) ther is no need remember this, so just
+ * return.
+ */
+ dev_info(p->dev,
+ "there is not valid maps for state %s\n", statename);
+ return 0;
+ }
+
+ /* 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);
+}
+
+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);
+ if (!propname)
+ return -ENOMEM;
+ 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)
+ statename = prop->name + strlen("pinctrl-");
+
+ /* 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_args: 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);