| /* | 
 |  * Device tree integration for the pin control subsystem | 
 |  * | 
 |  * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved. | 
 |  * | 
 |  * This program is free software; you can redistribute it and/or modify it | 
 |  * under the terms and conditions of the GNU General Public License, | 
 |  * version 2, as published by the Free Software Foundation. | 
 |  * | 
 |  * This program is distributed in the hope it will be useful, but WITHOUT | 
 |  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | 
 |  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for | 
 |  * more details. | 
 |  * | 
 |  * You should have received a copy of the GNU General Public License | 
 |  * along with this program.  If not, see <http://www.gnu.org/licenses/>. | 
 |  */ | 
 |  | 
 | #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 *pctldev, | 
 | 				const char *statename, | 
 | 				struct device_node *np_config) | 
 | { | 
 | 	struct device_node *np_pctldev; | 
 | 	const struct pinctrl_ops *ops; | 
 | 	int ret; | 
 | 	struct pinctrl_map *map; | 
 | 	unsigned num_maps; | 
 |  | 
 | 	/* Find the pin controller containing np_config */ | 
 | 	np_pctldev = of_node_get(np_config); | 
 | 	for (;;) { | 
 | 		np_pctldev = of_get_next_parent(np_pctldev); | 
 | 		if (!np_pctldev || of_node_is_root(np_pctldev)) { | 
 | 			dev_info(p->dev, "could not find pctldev for node %pOF, deferring probe\n", | 
 | 				np_config); | 
 | 			of_node_put(np_pctldev); | 
 | 			/* OK let's just assume this will appear later then */ | 
 | 			return -EPROBE_DEFER; | 
 | 		} | 
 | 		/* If we're creating a hog we can use the passed pctldev */ | 
 | 		if (pctldev && (np_pctldev == p->dev->of_node)) | 
 | 			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); |