// SPDX-License-Identifier: GPL-2.0
/*
 * Functions corresponding to enumeration type attributes under
 * BIOS Enumeration GUID for use with dell-wmi-sysman
 *
 *  Copyright (c) 2020 Dell Inc.
 */

#include "dell-wmi-sysman.h"

get_instance_id(enumeration);

static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
        int instance_id = get_enumeration_instance_id(kobj);
        union acpi_object *obj;
        ssize_t ret;

        if (instance_id < 0)
                return instance_id;

        /* need to use specific instance_id and guid combination to get right data */
        obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
        if (!obj)
                return -EIO;
        if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < ENUM_MIN_ELEMENTS ||
            obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) {
                kfree(obj);
                return -EIO;
        }
        ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer);
        kfree(obj);
        return ret;
}

/**
 * validate_enumeration_input() - Validate input of current_value against possible values
 * @instance_id: The instance on which input is validated
 * @buf: Input value
 */
static int validate_enumeration_input(int instance_id, const char *buf)
{
        char *options, *tmp, *p;
        int ret = -EINVAL;

        options = tmp = kstrdup(wmi_priv.enumeration_data[instance_id].possible_values,
                                 GFP_KERNEL);
        if (!options)
                return -ENOMEM;

        while ((p = strsep(&options, ";")) != NULL) {
                if (!*p)
                        continue;
                if (!strcasecmp(p, buf)) {
                        ret = 0;
                        break;
                }
        }

        kfree(tmp);
        return ret;
}

attribute_s_property_show(display_name_language_code, enumeration);
static struct kobj_attribute displ_langcode =
                __ATTR_RO(display_name_language_code);

attribute_s_property_show(display_name, enumeration);
static struct kobj_attribute displ_name =
                __ATTR_RO(display_name);

attribute_s_property_show(default_value, enumeration);
static struct kobj_attribute default_val =
                __ATTR_RO(default_value);

attribute_property_store(current_value, enumeration);
static struct kobj_attribute current_val =
                __ATTR_RW_MODE(current_value, 0600);

attribute_s_property_show(dell_modifier, enumeration);
static struct kobj_attribute modifier =
                __ATTR_RO(dell_modifier);

attribute_s_property_show(dell_value_modifier, enumeration);
static struct kobj_attribute value_modfr =
                __ATTR_RO(dell_value_modifier);

attribute_s_property_show(possible_values, enumeration);
static struct kobj_attribute poss_val =
                __ATTR_RO(possible_values);

static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
                         char *buf)
{
        return sprintf(buf, "enumeration\n");
}
static struct kobj_attribute type =
                __ATTR_RO(type);

static struct attribute *enumeration_attrs[] = {
        &displ_langcode.attr,
        &displ_name.attr,
        &default_val.attr,
        &current_val.attr,
        &modifier.attr,
        &value_modfr.attr,
        &poss_val.attr,
        &type.attr,
        NULL,
};

static const struct attribute_group enumeration_attr_group = {
        .attrs = enumeration_attrs,
};

int alloc_enum_data(void)
{
        int ret = 0;

        wmi_priv.enumeration_instances_count =
                get_instance_count(DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
        wmi_priv.enumeration_data = kzalloc_objs(struct enumeration_data,
                                                 wmi_priv.enumeration_instances_count);
        if (!wmi_priv.enumeration_data) {
                wmi_priv.enumeration_instances_count = 0;
                ret = -ENOMEM;
        }
        return ret;
}

/**
 * populate_enum_data() - Populate all properties of an instance under enumeration attribute
 * @enumeration_obj: ACPI object with enumeration data
 * @instance_id: The instance to enumerate
 * @attr_name_kobj: The parent kernel object
 * @enum_property_count: Total properties count under enumeration type
 */
int populate_enum_data(union acpi_object *enumeration_obj, int instance_id,
                        struct kobject *attr_name_kobj, u32 enum_property_count)
{
        int i, next_obj, value_modifier_count, possible_values_count;

        wmi_priv.enumeration_data[instance_id].attr_name_kobj = attr_name_kobj;
        if (check_property_type(enumeration, ATTR_NAME, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.enumeration_data[instance_id].attribute_name,
                enumeration_obj[ATTR_NAME].string.pointer);
        if (check_property_type(enumeration, DISPL_NAME_LANG_CODE, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.enumeration_data[instance_id].display_name_language_code,
                enumeration_obj[DISPL_NAME_LANG_CODE].string.pointer);
        if (check_property_type(enumeration, DISPLAY_NAME, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.enumeration_data[instance_id].display_name,
                enumeration_obj[DISPLAY_NAME].string.pointer);
        if (check_property_type(enumeration, DEFAULT_VAL, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.enumeration_data[instance_id].default_value,
                enumeration_obj[DEFAULT_VAL].string.pointer);
        if (check_property_type(enumeration, MODIFIER, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.enumeration_data[instance_id].dell_modifier,
                enumeration_obj[MODIFIER].string.pointer);

        next_obj = MODIFIER + 1;

        if (next_obj >= enum_property_count)
                return -EINVAL;

        if (check_property_type(enumeration, next_obj, ACPI_TYPE_INTEGER))
                return -EINVAL;
        value_modifier_count = (uintptr_t)enumeration_obj[next_obj++].string.pointer;

        for (i = 0; i < value_modifier_count; i++) {
                if (next_obj >= enum_property_count)
                        return -EINVAL;
                if (check_property_type(enumeration, next_obj, ACPI_TYPE_STRING))
                        return -EINVAL;
                strcat(wmi_priv.enumeration_data[instance_id].dell_value_modifier,
                        enumeration_obj[next_obj++].string.pointer);
                strcat(wmi_priv.enumeration_data[instance_id].dell_value_modifier, ";");
        }

        if (next_obj >= enum_property_count)
                return -EINVAL;

        if (check_property_type(enumeration, next_obj, ACPI_TYPE_INTEGER))
                return -EINVAL;
        possible_values_count = (uintptr_t) enumeration_obj[next_obj++].string.pointer;

        for (i = 0; i < possible_values_count; i++) {
                if (next_obj >= enum_property_count)
                        return -EINVAL;
                if (check_property_type(enumeration, next_obj, ACPI_TYPE_STRING))
                        return -EINVAL;
                strcat(wmi_priv.enumeration_data[instance_id].possible_values,
                        enumeration_obj[next_obj++].string.pointer);
                strcat(wmi_priv.enumeration_data[instance_id].possible_values, ";");
        }

        return sysfs_create_group(attr_name_kobj, &enumeration_attr_group);
}

/**
 * exit_enum_attributes() - Clear all attribute data
 *
 * Clears all data allocated for this group of attributes
 */
void exit_enum_attributes(void)
{
        int instance_id;

        for (instance_id = 0; instance_id < wmi_priv.enumeration_instances_count; instance_id++) {
                if (wmi_priv.enumeration_data[instance_id].attr_name_kobj)
                        sysfs_remove_group(wmi_priv.enumeration_data[instance_id].attr_name_kobj,
                                                                &enumeration_attr_group);
        }
        wmi_priv.enumeration_instances_count = 0;

        kfree(wmi_priv.enumeration_data);
        wmi_priv.enumeration_data = NULL;
}