drivers/pinctrl/pinconf.c - kernel/mindspeed - Git at Google

 /*
  * Core driver for the pin config portions of the pin control subsystem
  *
  * Copyright (C) 2011 ST-Ericsson SA
  * Written on behalf of Linaro for ST-Ericsson
  *
  * Author: Linus Walleij <linus.walleij@linaro.org>
  *
  * License terms: GNU General Public License (GPL) version 2
  */
 #define pr_fmt(fmt) "pinconfig core: " fmt

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/device.h>
 #include <linux/slab.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>
 #include <linux/pinctrl/machine.h>
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/pinctrl/pinconf.h>
 #include "core.h"
 #include "pinconf.h"

 int pinconf_check_ops(struct pinctrl_dev *pctldev)
 {
 	const struct pinconf_ops *ops = pctldev->desc->confops;

 	/* We have to be able to config the pins in SOME way */
 	if (!ops->pin_config_set && !ops->pin_config_group_set) {
 		dev_err(pctldev->dev,
 			"pinconf has to be able to set a pins config\n");
 		return -EINVAL;
 	}
 	return 0;
 }

 int pinconf_validate_map(struct pinctrl_map const *map, int i)
 {
 	if (!map->data.configs.group_or_pin) {
 		pr_err("failed to register map %s (%d): no group/pin given\n",
 		       map->name, i);
 		return -EINVAL;
 	}

 	if (!map->data.configs.num_configs ||
 			!map->data.configs.configs) {
 		pr_err("failed to register map %s (%d): no configs given\n",
 		       map->name, i);
 		return -EINVAL;
 	}

 	return 0;
 }

 int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
 			   unsigned long *config)
 {
 	const struct pinconf_ops *ops = pctldev->desc->confops;

 	if (!ops || !ops->pin_config_get) {
 		dev_dbg(pctldev->dev, "cannot get pin configuration, missing "
 			"pin_config_get() function in driver\n");
 		return -ENOTSUPP;
 	}

 	return ops->pin_config_get(pctldev, pin, config);
 }

 int pin_config_group_get(const char *dev_name, const char *pin_group,
 			 unsigned long *config)
 {
 	struct pinctrl_dev *pctldev;
 	const struct pinconf_ops *ops;
 	int selector, ret;

 	pctldev = get_pinctrl_dev_from_devname(dev_name);
 	if (!pctldev) {
 		ret = -EINVAL;
 		return ret;
 	}

 	mutex_lock(&pctldev->mutex);

 	ops = pctldev->desc->confops;

 	if (!ops || !ops->pin_config_group_get) {
 		dev_dbg(pctldev->dev, "cannot get configuration for pin "
 			"group, missing group config get function in "
 			"driver\n");
 		ret = -ENOTSUPP;
 		goto unlock;
 	}

 	selector = pinctrl_get_group_selector(pctldev, pin_group);
 	if (selector < 0) {
 		ret = selector;
 		goto unlock;
 	}

 	ret = ops->pin_config_group_get(pctldev, selector, config);

 unlock:
 	mutex_unlock(&pctldev->mutex);
 	return ret;
 }

 int pinconf_map_to_setting(struct pinctrl_map const *map,
 			  struct pinctrl_setting *setting)
 {
 	struct pinctrl_dev *pctldev = setting->pctldev;
 	int pin;

 	switch (setting->type) {
 	case PIN_MAP_TYPE_CONFIGS_PIN:
 		pin = pin_get_from_name(pctldev,
 					map->data.configs.group_or_pin);
 		if (pin < 0) {
 			dev_err(pctldev->dev, "could not map pin config for \"%s\"",
 				map->data.configs.group_or_pin);
 			return pin;
 		}
 		setting->data.configs.group_or_pin = pin;
 		break;
 	case PIN_MAP_TYPE_CONFIGS_GROUP:
 		pin = pinctrl_get_group_selector(pctldev,
 					 map->data.configs.group_or_pin);
 		if (pin < 0) {
 			dev_err(pctldev->dev, "could not map group config for \"%s\"",
 				map->data.configs.group_or_pin);
 			return pin;
 		}
 		setting->data.configs.group_or_pin = pin;
 		break;
 	default:
 		return -EINVAL;
 	}

 	setting->data.configs.num_configs = map->data.configs.num_configs;
 	setting->data.configs.configs = map->data.configs.configs;

 	return 0;
 }

 void pinconf_free_setting(struct pinctrl_setting const *setting)
 {
 }

 int pinconf_apply_setting(struct pinctrl_setting const *setting)
 {
 	struct pinctrl_dev *pctldev = setting->pctldev;
 	const struct pinconf_ops *ops = pctldev->desc->confops;
 	int ret;

 	if (!ops) {
 		dev_err(pctldev->dev, "missing confops\n");
 		return -EINVAL;
 	}

 	switch (setting->type) {
 	case PIN_MAP_TYPE_CONFIGS_PIN:
 		if (!ops->pin_config_set) {
 			dev_err(pctldev->dev, "missing pin_config_set op\n");
 			return -EINVAL;
 		}
 		ret = ops->pin_config_set(pctldev,
 				setting->data.configs.group_or_pin,
 				setting->data.configs.configs,
 				setting->data.configs.num_configs);
 		if (ret < 0) {
 			dev_err(pctldev->dev,
 				"pin_config_set op failed for pin %d\n",
 				setting->data.configs.group_or_pin);
 			return ret;
 		}
 		break;
 	case PIN_MAP_TYPE_CONFIGS_GROUP:
 		if (!ops->pin_config_group_set) {
 			dev_err(pctldev->dev,
 				"missing pin_config_group_set op\n");
 			return -EINVAL;
 		}
 		ret = ops->pin_config_group_set(pctldev,
 				setting->data.configs.group_or_pin,
 				setting->data.configs.configs,
 				setting->data.configs.num_configs);
 		if (ret < 0) {
 			dev_err(pctldev->dev,
 				"pin_config_group_set op failed for group %d\n",
 				setting->data.configs.group_or_pin);
 			return ret;
 		}
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 #ifdef CONFIG_DEBUG_FS

 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
 {
 	struct pinctrl_dev *pctldev;
 	const struct pinconf_ops *confops;
 	int i;

 	pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
 	if (pctldev)
 		confops = pctldev->desc->confops;
 	else
 		confops = NULL;

 	switch (map->type) {
 	case PIN_MAP_TYPE_CONFIGS_PIN:
 		seq_printf(s, "pin ");
 		break;
 	case PIN_MAP_TYPE_CONFIGS_GROUP:
 		seq_printf(s, "group ");
 		break;
 	default:
 		break;
 	}

 	seq_printf(s, "%s\n", map->data.configs.group_or_pin);

 	for (i = 0; i < map->data.configs.num_configs; i++) {
 		seq_printf(s, "config ");
 		if (confops && confops->pin_config_config_dbg_show)
 			confops->pin_config_config_dbg_show(pctldev, s,
 						map->data.configs.configs[i]);
 		else
 			seq_printf(s, "%08lx", map->data.configs.configs[i]);
 		seq_printf(s, "\n");
 	}
 }

 void pinconf_show_setting(struct seq_file *s,
 			  struct pinctrl_setting const *setting)
 {
 	struct pinctrl_dev *pctldev = setting->pctldev;
 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 	const struct pinconf_ops *confops = pctldev->desc->confops;
 	struct pin_desc *desc;
 	int i;

 	switch (setting->type) {
 	case PIN_MAP_TYPE_CONFIGS_PIN:
 		desc = pin_desc_get(setting->pctldev,
 				    setting->data.configs.group_or_pin);
 		seq_printf(s, "pin %s (%d)",
 			   desc->name ? desc->name : "unnamed",
 			   setting->data.configs.group_or_pin);
 		break;
 	case PIN_MAP_TYPE_CONFIGS_GROUP:
 		seq_printf(s, "group %s (%d)",
 			   pctlops->get_group_name(pctldev,
 					setting->data.configs.group_or_pin),
 			   setting->data.configs.group_or_pin);
 		break;
 	default:
 		break;
 	}

 	/*
 	 * FIXME: We should really get the pin controler to dump the config
 	 * values, so they can be decoded to something meaningful.
 	 */
 	for (i = 0; i < setting->data.configs.num_configs; i++) {
 		seq_printf(s, " ");
 		if (confops && confops->pin_config_config_dbg_show)
 			confops->pin_config_config_dbg_show(pctldev, s,
 				setting->data.configs.configs[i]);
 		else
 			seq_printf(s, "%08lx",
 				   setting->data.configs.configs[i]);
 	}

 	seq_printf(s, "\n");
 }

 static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
 			     struct seq_file *s, int pin)
 {
 	const struct pinconf_ops *ops = pctldev->desc->confops;

 	/* no-op when not using generic pin config */
 	pinconf_generic_dump_pins(pctldev, s, NULL, pin);
 	if (ops && ops->pin_config_dbg_show)
 		ops->pin_config_dbg_show(pctldev, s, pin);
 }

 static int pinconf_pins_show(struct seq_file *s, void *what)
 {
 	struct pinctrl_dev *pctldev = s->private;
 	unsigned i, pin;

 	seq_puts(s, "Pin config settings per pin\n");
 	seq_puts(s, "Format: pin (name): configs\n");

 	mutex_lock(&pctldev->mutex);

 	/* 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):", pin,
 			   desc->name ? desc->name : "unnamed");

 		pinconf_dump_pin(pctldev, s, pin);

 		seq_printf(s, "\n");
 	}

 	mutex_unlock(&pctldev->mutex);

 	return 0;
 }

 static void pinconf_dump_group(struct pinctrl_dev *pctldev,
 			       struct seq_file *s, unsigned selector,
 			       const char *gname)
 {
 	const struct pinconf_ops *ops = pctldev->desc->confops;

 	/* no-op when not using generic pin config */
 	pinconf_generic_dump_pins(pctldev, s, gname, 0);
 	if (ops && ops->pin_config_group_dbg_show)
 		ops->pin_config_group_dbg_show(pctldev, s, selector);
 }

 static int pinconf_groups_show(struct seq_file *s, void *what)
 {
 	struct pinctrl_dev *pctldev = s->private;
 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 	unsigned ngroups = pctlops->get_groups_count(pctldev);
 	unsigned selector = 0;

 	seq_puts(s, "Pin config settings per pin group\n");
 	seq_puts(s, "Format: group (name): configs\n");

 	while (selector < ngroups) {
 		const char *gname = pctlops->get_group_name(pctldev, selector);

 		seq_printf(s, "%u (%s):", selector, gname);
 		pinconf_dump_group(pctldev, s, selector, gname);
 		seq_printf(s, "\n");

 		selector++;
 	}

 	return 0;
 }

 static int pinconf_pins_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, pinconf_pins_show, inode->i_private);
 }

 static int pinconf_groups_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, pinconf_groups_show, inode->i_private);
 }

 static const struct file_operations pinconf_pins_ops = {
 	.open		= pinconf_pins_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 static const struct file_operations pinconf_groups_ops = {
 	.open		= pinconf_groups_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };

 #define MAX_NAME_LEN 15

 struct dbg_cfg {
 	enum pinctrl_map_type map_type;
 	char dev_name[MAX_NAME_LEN+1];
 	char state_name[MAX_NAME_LEN+1];
 	char pin_name[MAX_NAME_LEN+1];
 };

 /*
  * Goal is to keep this structure as global in order to simply read the
  * pinconf-config file after a write to check config is as expected
  */
 static struct dbg_cfg pinconf_dbg_conf;

 /**
  * pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
  * map, of the dev/pin/state that was last written to pinconf-config file.
  * @s: string filled in  with config description
  * @d: not used
  */
 static int pinconf_dbg_config_print(struct seq_file *s, void *d)
 {
 	struct pinctrl_maps *maps_node;
 	const struct pinctrl_map *map;
 	const struct pinctrl_map *found = NULL;
 	struct pinctrl_dev *pctldev;
 	const struct pinconf_ops *confops = NULL;
 	struct dbg_cfg *dbg = &pinconf_dbg_conf;
 	int i, j;
 	unsigned long config;

 	mutex_lock(&pinctrl_maps_mutex);

 	/* Parse the pinctrl map and look for the elected pin/state */
 	for_each_maps(maps_node, i, map) {
 		if (map->type != dbg->map_type)
 			continue;
 		if (strcmp(map->dev_name, dbg->dev_name))
 			continue;
 		if (strcmp(map->name, dbg->state_name))
 			continue;

 		for (j = 0; j < map->data.configs.num_configs; j++) {
 			if (!strcmp(map->data.configs.group_or_pin,
 					dbg->pin_name)) {
 				/* We found the right pin / state */
 				found = map;
 				break;
 			}
 		}
 	}

 	if (!found) {
 		seq_printf(s, "No config found for dev/state/pin, expected:\n");
 		seq_printf(s, "Searched dev:%s\n", dbg->dev_name);
 		seq_printf(s, "Searched state:%s\n", dbg->state_name);
 		seq_printf(s, "Searched pin:%s\n", dbg->pin_name);
 		seq_printf(s, "Use: modify config_pin <devname> "\
 				"<state> <pinname> <value>\n");
 		goto exit;
 	}

 	pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
 	config = *found->data.configs.configs;
 	seq_printf(s, "Dev %s has config of %s in state %s: 0x%08lX\n",
 			dbg->dev_name, dbg->pin_name,
 			dbg->state_name, config);

 	if (pctldev)
 		confops = pctldev->desc->confops;

 	if (confops && confops->pin_config_config_dbg_show)
 		confops->pin_config_config_dbg_show(pctldev, s, config);

 exit:
 	mutex_unlock(&pinctrl_maps_mutex);

 	return 0;
 }

 /**
  * pinconf_dbg_config_write() - modify the pinctrl config in the pinctrl
  * map, of a dev/pin/state entry based on user entries to pinconf-config
  * @user_buf: contains the modification request with expected format:
  *     modify config_pin <devicename> <state> <pinname> <newvalue>
  * modify is literal string, alternatives like add/delete not supported yet
  * config_pin is literal, alternatives like config_mux not supported yet
  * <devicename> <state> <pinname> are values that should match the pinctrl-maps
  * <newvalue> reflects the new config and is driver dependant
  */
 static ssize_t pinconf_dbg_config_write(struct file *file,
 	const char __user *user_buf, size_t count, loff_t *ppos)
 {
 	struct pinctrl_maps *maps_node;
 	const struct pinctrl_map *map;
 	const struct pinctrl_map *found = NULL;
 	struct pinctrl_dev *pctldev;
 	const struct pinconf_ops *confops = NULL;
 	struct dbg_cfg *dbg = &pinconf_dbg_conf;
 	const struct pinctrl_map_configs *configs;
 	char config[MAX_NAME_LEN+1];
 	char buf[128];
 	char *b = &buf[0];
 	int buf_size;
 	char *token;
 	int i;

 	/* Get userspace string and assure termination */
 	buf_size = min(count, sizeof(buf) - 1);
 	if (copy_from_user(buf, user_buf, buf_size))
 		return -EFAULT;
 	buf[buf_size] = 0;

 	/*
 	 * need to parse entry and extract parameters:
 	 * modify configs_pin devicename state pinname newvalue
 	 */

 	/* Get arg: 'modify' */
 	token = strsep(&b, " ");
 	if (!token)
 		return -EINVAL;
 	if (strcmp(token, "modify"))
 		return -EINVAL;

 	/* Get arg type: "config_pin" type supported so far */
 	token = strsep(&b, " ");
 	if (!token)
 		return -EINVAL;
 	if (strcmp(token, "config_pin"))
 		return -EINVAL;
 	dbg->map_type = PIN_MAP_TYPE_CONFIGS_PIN;

 	/* get arg 'device_name' */
 	token = strsep(&b, " ");
 	if (token == NULL)
 		return -EINVAL;
 	if (strlen(token) >= MAX_NAME_LEN)
 		return -EINVAL;
 	strncpy(dbg->dev_name, token, MAX_NAME_LEN);

 	/* get arg 'state_name' */
 	token = strsep(&b, " ");
 	if (token == NULL)
 		return -EINVAL;
 	if (strlen(token) >= MAX_NAME_LEN)
 		return -EINVAL;
 	strncpy(dbg->state_name, token, MAX_NAME_LEN);

 	/* get arg 'pin_name' */
 	token = strsep(&b, " ");
 	if (token == NULL)
 		return -EINVAL;
 	if (strlen(token) >= MAX_NAME_LEN)
 		return -EINVAL;
 	strncpy(dbg->pin_name, token, MAX_NAME_LEN);

 	/* get new_value of config' */
 	token = strsep(&b, " ");
 	if (token == NULL)
 		return -EINVAL;
 	if (strlen(token) >= MAX_NAME_LEN)
 		return -EINVAL;
 	strncpy(config, token, MAX_NAME_LEN);

 	mutex_lock(&pinctrl_maps_mutex);

 	/* Parse the pinctrl map and look for the selected dev/state/pin */
 	for_each_maps(maps_node, i, map) {
 		if (strcmp(map->dev_name, dbg->dev_name))
 			continue;
 		if (map->type != dbg->map_type)
 			continue;
 		if (strcmp(map->name, dbg->state_name))
 			continue;

 		/*  we found the right pin / state, so overwrite config */
 		if (!strcmp(map->data.configs.group_or_pin, dbg->pin_name)) {
 			found = map;
 			break;
 		}
 	}

 	if (!found) {
 		count = -EINVAL;
 		goto exit;
 	}

 	pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
 	if (pctldev)
 		confops = pctldev->desc->confops;

 	if (confops && confops->pin_config_dbg_parse_modify) {
 		configs = &found->data.configs;
 		for (i = 0; i < configs->num_configs; i++) {
 			confops->pin_config_dbg_parse_modify(pctldev,
 						     config,
 						     &configs->configs[i]);
 		}
 	}

 exit:
 	mutex_unlock(&pinctrl_maps_mutex);

 	return count;
 }

 static int pinconf_dbg_config_open(struct inode *inode, struct file *file)
 {
 	return single_open(file, pinconf_dbg_config_print, inode->i_private);
 }

 static const struct file_operations pinconf_dbg_pinconfig_fops = {
 	.open = pinconf_dbg_config_open,
 	.write = pinconf_dbg_config_write,
 	.read = seq_read,
 	.llseek = seq_lseek,
 	.release = single_release,
 	.owner = THIS_MODULE,
 };

 void pinconf_init_device_debugfs(struct dentry *devroot,
 			 struct pinctrl_dev *pctldev)
 {
 	debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
 			    devroot, pctldev, &pinconf_pins_ops);
 	debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
 			    devroot, pctldev, &pinconf_groups_ops);
 	debugfs_create_file("pinconf-config",  (S_IRUGO | S_IWUSR | S_IWGRP),
 			    devroot, pctldev, &pinconf_dbg_pinconfig_fops);
 }

 #endif
	/*
	* Core driver for the pin config portions of the pin control subsystem
	*
	* Copyright (C) 2011 ST-Ericsson SA
	* Written on behalf of Linaro for ST-Ericsson
	*
	* Author: Linus Walleij <linus.walleij@linaro.org>
	*
	* License terms: GNU General Public License (GPL) version 2
	*/
	#define pr_fmt(fmt) "pinconfig core: " fmt

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/device.h>
	#include <linux/slab.h>
	#include <linux/debugfs.h>
	#include <linux/seq_file.h>
	#include <linux/uaccess.h>
	#include <linux/pinctrl/machine.h>
	#include <linux/pinctrl/pinctrl.h>
	#include <linux/pinctrl/pinconf.h>
	#include "core.h"
	#include "pinconf.h"

	int pinconf_check_ops(struct pinctrl_dev *pctldev)
	{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	/* We have to be able to config the pins in SOME way */
	if (!ops->pin_config_set && !ops->pin_config_group_set) {
	dev_err(pctldev->dev,
	"pinconf has to be able to set a pins config\n");
	return -EINVAL;
	}
	return 0;
	}

	int pinconf_validate_map(struct pinctrl_map const *map, int i)
	{
	if (!map->data.configs.group_or_pin) {
	pr_err("failed to register map %s (%d): no group/pin given\n",
	map->name, i);
	return -EINVAL;
	}

	if (!map->data.configs.num_configs \|\|
	!map->data.configs.configs) {
	pr_err("failed to register map %s (%d): no configs given\n",
	map->name, i);
	return -EINVAL;
	}

	return 0;
	}

	int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
	unsigned long *config)
	{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	if (!ops \|\| !ops->pin_config_get) {
	dev_dbg(pctldev->dev, "cannot get pin configuration, missing "
	"pin_config_get() function in driver\n");
	return -ENOTSUPP;
	}

	return ops->pin_config_get(pctldev, pin, config);
	}

	int pin_config_group_get(const char dev_name, const char pin_group,
	unsigned long *config)
	{
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *ops;
	int selector, ret;

	pctldev = get_pinctrl_dev_from_devname(dev_name);
	if (!pctldev) {
	ret = -EINVAL;
	return ret;
	}

	mutex_lock(&pctldev->mutex);

	ops = pctldev->desc->confops;

	if (!ops \|\| !ops->pin_config_group_get) {
	dev_dbg(pctldev->dev, "cannot get configuration for pin "
	"group, missing group config get function in "
	"driver\n");
	ret = -ENOTSUPP;
	goto unlock;
	}

	selector = pinctrl_get_group_selector(pctldev, pin_group);
	if (selector < 0) {
	ret = selector;
	goto unlock;
	}

	ret = ops->pin_config_group_get(pctldev, selector, config);

	unlock:
	mutex_unlock(&pctldev->mutex);
	return ret;
	}

	int pinconf_map_to_setting(struct pinctrl_map const *map,
	struct pinctrl_setting *setting)
	{
	struct pinctrl_dev *pctldev = setting->pctldev;
	int pin;

	switch (setting->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
	pin = pin_get_from_name(pctldev,
	map->data.configs.group_or_pin);
	if (pin < 0) {
	dev_err(pctldev->dev, "could not map pin config for \"%s\"",
	map->data.configs.group_or_pin);
	return pin;
	}
	setting->data.configs.group_or_pin = pin;
	break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
	pin = pinctrl_get_group_selector(pctldev,
	map->data.configs.group_or_pin);
	if (pin < 0) {
	dev_err(pctldev->dev, "could not map group config for \"%s\"",
	map->data.configs.group_or_pin);
	return pin;
	}
	setting->data.configs.group_or_pin = pin;
	break;
	default:
	return -EINVAL;
	}

	setting->data.configs.num_configs = map->data.configs.num_configs;
	setting->data.configs.configs = map->data.configs.configs;

	return 0;
	}

	void pinconf_free_setting(struct pinctrl_setting const *setting)
	{
	}

	int pinconf_apply_setting(struct pinctrl_setting const *setting)
	{
	struct pinctrl_dev *pctldev = setting->pctldev;
	const struct pinconf_ops *ops = pctldev->desc->confops;
	int ret;

	if (!ops) {
	dev_err(pctldev->dev, "missing confops\n");
	return -EINVAL;
	}

	switch (setting->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
	if (!ops->pin_config_set) {
	dev_err(pctldev->dev, "missing pin_config_set op\n");
	return -EINVAL;
	}
	ret = ops->pin_config_set(pctldev,
	setting->data.configs.group_or_pin,
	setting->data.configs.configs,
	setting->data.configs.num_configs);
	if (ret < 0) {
	dev_err(pctldev->dev,
	"pin_config_set op failed for pin %d\n",
	setting->data.configs.group_or_pin);
	return ret;
	}
	break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
	if (!ops->pin_config_group_set) {
	dev_err(pctldev->dev,
	"missing pin_config_group_set op\n");
	return -EINVAL;
	}
	ret = ops->pin_config_group_set(pctldev,
	setting->data.configs.group_or_pin,
	setting->data.configs.configs,
	setting->data.configs.num_configs);
	if (ret < 0) {
	dev_err(pctldev->dev,
	"pin_config_group_set op failed for group %d\n",
	setting->data.configs.group_or_pin);
	return ret;
	}
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}

	#ifdef CONFIG_DEBUG_FS

	void pinconf_show_map(struct seq_file s, struct pinctrl_map const map)
	{
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *confops;
	int i;

	pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
	if (pctldev)
	confops = pctldev->desc->confops;
	else
	confops = NULL;

	switch (map->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
	seq_printf(s, "pin ");
	break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
	seq_printf(s, "group ");
	break;
	default:
	break;
	}

	seq_printf(s, "%s\n", map->data.configs.group_or_pin);

	for (i = 0; i < map->data.configs.num_configs; i++) {
	seq_printf(s, "config ");
	if (confops && confops->pin_config_config_dbg_show)
	confops->pin_config_config_dbg_show(pctldev, s,
	map->data.configs.configs[i]);
	else
	seq_printf(s, "%08lx", map->data.configs.configs[i]);
	seq_printf(s, "\n");
	}
	}

	void pinconf_show_setting(struct seq_file *s,
	struct pinctrl_setting const *setting)
	{
	struct pinctrl_dev *pctldev = setting->pctldev;
	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
	const struct pinconf_ops *confops = pctldev->desc->confops;
	struct pin_desc *desc;
	int i;

	switch (setting->type) {
	case PIN_MAP_TYPE_CONFIGS_PIN:
	desc = pin_desc_get(setting->pctldev,
	setting->data.configs.group_or_pin);
	seq_printf(s, "pin %s (%d)",
	desc->name ? desc->name : "unnamed",
	setting->data.configs.group_or_pin);
	break;
	case PIN_MAP_TYPE_CONFIGS_GROUP:
	seq_printf(s, "group %s (%d)",
	pctlops->get_group_name(pctldev,
	setting->data.configs.group_or_pin),
	setting->data.configs.group_or_pin);
	break;
	default:
	break;
	}

	/*
	* FIXME: We should really get the pin controler to dump the config
	* values, so they can be decoded to something meaningful.
	*/
	for (i = 0; i < setting->data.configs.num_configs; i++) {
	seq_printf(s, " ");
	if (confops && confops->pin_config_config_dbg_show)
	confops->pin_config_config_dbg_show(pctldev, s,
	setting->data.configs.configs[i]);
	else
	seq_printf(s, "%08lx",
	setting->data.configs.configs[i]);
	}

	seq_printf(s, "\n");
	}

	static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
	struct seq_file *s, int pin)
	{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	/* no-op when not using generic pin config */
	pinconf_generic_dump_pins(pctldev, s, NULL, pin);
	if (ops && ops->pin_config_dbg_show)
	ops->pin_config_dbg_show(pctldev, s, pin);
	}

	static int pinconf_pins_show(struct seq_file s, void what)
	{
	struct pinctrl_dev *pctldev = s->private;
	unsigned i, pin;

	seq_puts(s, "Pin config settings per pin\n");
	seq_puts(s, "Format: pin (name): configs\n");

	mutex_lock(&pctldev->mutex);

	/* 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):", pin,
	desc->name ? desc->name : "unnamed");

	pinconf_dump_pin(pctldev, s, pin);

	seq_printf(s, "\n");
	}

	mutex_unlock(&pctldev->mutex);

	return 0;
	}

	static void pinconf_dump_group(struct pinctrl_dev *pctldev,
	struct seq_file *s, unsigned selector,
	const char *gname)
	{
	const struct pinconf_ops *ops = pctldev->desc->confops;

	/* no-op when not using generic pin config */
	pinconf_generic_dump_pins(pctldev, s, gname, 0);
	if (ops && ops->pin_config_group_dbg_show)
	ops->pin_config_group_dbg_show(pctldev, s, selector);
	}

	static int pinconf_groups_show(struct seq_file s, void what)
	{
	struct pinctrl_dev *pctldev = s->private;
	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
	unsigned ngroups = pctlops->get_groups_count(pctldev);
	unsigned selector = 0;

	seq_puts(s, "Pin config settings per pin group\n");
	seq_puts(s, "Format: group (name): configs\n");

	while (selector < ngroups) {
	const char *gname = pctlops->get_group_name(pctldev, selector);

	seq_printf(s, "%u (%s):", selector, gname);
	pinconf_dump_group(pctldev, s, selector, gname);
	seq_printf(s, "\n");

	selector++;
	}

	return 0;
	}

	static int pinconf_pins_open(struct inode inode, struct file file)
	{
	return single_open(file, pinconf_pins_show, inode->i_private);
	}

	static int pinconf_groups_open(struct inode inode, struct file file)
	{
	return single_open(file, pinconf_groups_show, inode->i_private);
	}

	static const struct file_operations pinconf_pins_ops = {
	.open = pinconf_pins_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	static const struct file_operations pinconf_groups_ops = {
	.open = pinconf_groups_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	};

	#define MAX_NAME_LEN 15

	struct dbg_cfg {
	enum pinctrl_map_type map_type;
	char dev_name[MAX_NAME_LEN+1];
	char state_name[MAX_NAME_LEN+1];
	char pin_name[MAX_NAME_LEN+1];
	};

	/*
	* Goal is to keep this structure as global in order to simply read the
	* pinconf-config file after a write to check config is as expected
	*/
	static struct dbg_cfg pinconf_dbg_conf;

	/**
	* pinconf_dbg_config_print() - display the pinctrl config from the pinctrl
	* map, of the dev/pin/state that was last written to pinconf-config file.
	* @s: string filled in with config description
	* @d: not used
	*/
	static int pinconf_dbg_config_print(struct seq_file s, void d)
	{
	struct pinctrl_maps *maps_node;
	const struct pinctrl_map *map;
	const struct pinctrl_map *found = NULL;
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *confops = NULL;
	struct dbg_cfg *dbg = &pinconf_dbg_conf;
	int i, j;
	unsigned long config;

	mutex_lock(&pinctrl_maps_mutex);

	/* Parse the pinctrl map and look for the elected pin/state */
	for_each_maps(maps_node, i, map) {
	if (map->type != dbg->map_type)
	continue;
	if (strcmp(map->dev_name, dbg->dev_name))
	continue;
	if (strcmp(map->name, dbg->state_name))
	continue;

	for (j = 0; j < map->data.configs.num_configs; j++) {
	if (!strcmp(map->data.configs.group_or_pin,
	dbg->pin_name)) {
	/* We found the right pin / state */
	found = map;
	break;
	}
	}
	}

	if (!found) {
	seq_printf(s, "No config found for dev/state/pin, expected:\n");
	seq_printf(s, "Searched dev:%s\n", dbg->dev_name);
	seq_printf(s, "Searched state:%s\n", dbg->state_name);
	seq_printf(s, "Searched pin:%s\n", dbg->pin_name);
	seq_printf(s, "Use: modify config_pin <devname> "\
	"<state> <pinname> <value>\n");
	goto exit;
	}

	pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
	config = *found->data.configs.configs;
	seq_printf(s, "Dev %s has config of %s in state %s: 0x%08lX\n",
	dbg->dev_name, dbg->pin_name,
	dbg->state_name, config);

	if (pctldev)
	confops = pctldev->desc->confops;

	if (confops && confops->pin_config_config_dbg_show)
	confops->pin_config_config_dbg_show(pctldev, s, config);

	exit:
	mutex_unlock(&pinctrl_maps_mutex);

	return 0;
	}

	/**
	* pinconf_dbg_config_write() - modify the pinctrl config in the pinctrl
	* map, of a dev/pin/state entry based on user entries to pinconf-config
	* @user_buf: contains the modification request with expected format:
	* modify config_pin <devicename> <state> <pinname> <newvalue>
	* modify is literal string, alternatives like add/delete not supported yet
	* config_pin is literal, alternatives like config_mux not supported yet
	* <devicename> <state> <pinname> are values that should match the pinctrl-maps
	* <newvalue> reflects the new config and is driver dependant
	*/
	static ssize_t pinconf_dbg_config_write(struct file *file,
	const char __user user_buf, size_t count, loff_t ppos)
	{
	struct pinctrl_maps *maps_node;
	const struct pinctrl_map *map;
	const struct pinctrl_map *found = NULL;
	struct pinctrl_dev *pctldev;
	const struct pinconf_ops *confops = NULL;
	struct dbg_cfg *dbg = &pinconf_dbg_conf;
	const struct pinctrl_map_configs *configs;
	char config[MAX_NAME_LEN+1];
	char buf[128];
	char *b = &buf[0];
	int buf_size;
	char *token;
	int i;

	/* Get userspace string and assure termination */
	buf_size = min(count, sizeof(buf) - 1);
	if (copy_from_user(buf, user_buf, buf_size))
	return -EFAULT;
	buf[buf_size] = 0;

	/*
	* need to parse entry and extract parameters:
	* modify configs_pin devicename state pinname newvalue
	*/

	/* Get arg: 'modify' */
	token = strsep(&b, " ");
	if (!token)
	return -EINVAL;
	if (strcmp(token, "modify"))
	return -EINVAL;

	/* Get arg type: "config_pin" type supported so far */
	token = strsep(&b, " ");
	if (!token)
	return -EINVAL;
	if (strcmp(token, "config_pin"))
	return -EINVAL;
	dbg->map_type = PIN_MAP_TYPE_CONFIGS_PIN;

	/* get arg 'device_name' */
	token = strsep(&b, " ");
	if (token == NULL)
	return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
	return -EINVAL;
	strncpy(dbg->dev_name, token, MAX_NAME_LEN);

	/* get arg 'state_name' */
	token = strsep(&b, " ");
	if (token == NULL)
	return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
	return -EINVAL;
	strncpy(dbg->state_name, token, MAX_NAME_LEN);

	/* get arg 'pin_name' */
	token = strsep(&b, " ");
	if (token == NULL)
	return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
	return -EINVAL;
	strncpy(dbg->pin_name, token, MAX_NAME_LEN);

	/* get new_value of config' */
	token = strsep(&b, " ");
	if (token == NULL)
	return -EINVAL;
	if (strlen(token) >= MAX_NAME_LEN)
	return -EINVAL;
	strncpy(config, token, MAX_NAME_LEN);

	mutex_lock(&pinctrl_maps_mutex);

	/* Parse the pinctrl map and look for the selected dev/state/pin */
	for_each_maps(maps_node, i, map) {
	if (strcmp(map->dev_name, dbg->dev_name))
	continue;
	if (map->type != dbg->map_type)
	continue;
	if (strcmp(map->name, dbg->state_name))
	continue;

	/* we found the right pin / state, so overwrite config */
	if (!strcmp(map->data.configs.group_or_pin, dbg->pin_name)) {
	found = map;
	break;
	}
	}

	if (!found) {
	count = -EINVAL;
	goto exit;
	}

	pctldev = get_pinctrl_dev_from_devname(found->ctrl_dev_name);
	if (pctldev)
	confops = pctldev->desc->confops;

	if (confops && confops->pin_config_dbg_parse_modify) {
	configs = &found->data.configs;
	for (i = 0; i < configs->num_configs; i++) {
	confops->pin_config_dbg_parse_modify(pctldev,
	config,
	&configs->configs[i]);
	}
	}

	exit:
	mutex_unlock(&pinctrl_maps_mutex);

	return count;
	}

	static int pinconf_dbg_config_open(struct inode inode, struct file file)
	{
	return single_open(file, pinconf_dbg_config_print, inode->i_private);
	}

	static const struct file_operations pinconf_dbg_pinconfig_fops = {
	.open = pinconf_dbg_config_open,
	.write = pinconf_dbg_config_write,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
	.owner = THIS_MODULE,
	};

	void pinconf_init_device_debugfs(struct dentry *devroot,
	struct pinctrl_dev *pctldev)
	{
	debugfs_create_file("pinconf-pins", S_IFREG \| S_IRUGO,
	devroot, pctldev, &pinconf_pins_ops);
	debugfs_create_file("pinconf-groups", S_IFREG \| S_IRUGO,
	devroot, pctldev, &pinconf_groups_ops);
	debugfs_create_file("pinconf-config", (S_IRUGO \| S_IWUSR \| S_IWGRP),
	devroot, pctldev, &pinconf_dbg_pinconfig_fops);
	}

	#endif