/*
 * 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/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(const struct pinctrl_map *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, .pin_config_get missing 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(const struct pinctrl_map *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(const struct pinctrl_setting *setting)
{
}

int pinconf_apply_setting(const struct pinctrl_setting *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;
}

int pinconf_set_config(struct pinctrl_dev *pctldev, unsigned pin,
		       unsigned long *configs, size_t nconfigs)
{
	const struct pinconf_ops *ops;

	ops = pctldev->desc->confops;
	if (!ops || !ops->pin_config_set)
		return -ENOTSUPP;

	return ops->pin_config_set(pctldev, pin, configs, nconfigs);
}

#ifdef CONFIG_DEBUG_FS

static void pinconf_show_config(struct seq_file *s, struct pinctrl_dev *pctldev,
		      unsigned long *configs, unsigned num_configs)
{
	const struct pinconf_ops *confops;
	int i;

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

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

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

	pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);

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

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

	pinconf_show_config(s, pctldev, map->data.configs.configs,
			    map->data.configs.num_configs);
}

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

	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,
			   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 controller to dump the config
	 * values, so they can be decoded to something meaningful.
	 */
	pinconf_show_config(s, pctldev, setting->data.configs.configs,
			    setting->data.configs.num_configs);
}

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)
			continue;

		seq_printf(s, "pin %d (%s): ", pin, desc->name);

		pinconf_dump_pin(pctldev, s, pin);
		seq_putc(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_putc(s, '\n');
		selector++;
	}

	return 0;
}

DEFINE_SHOW_ATTRIBUTE(pinconf_pins);
DEFINE_SHOW_ATTRIBUTE(pinconf_groups);

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_fops);
	debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
			    devroot, pctldev, &pinconf_groups_fops);
}

#endif