| // 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) |
| { |
| 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_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++) { |
| 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_map(map, num_maps, false); |
| |
| 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); |
| } |
| |
| 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) |
| 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_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); |