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

#include "dell-wmi-sysman.h"

enum string_properties {MIN_LEN = 6, MAX_LEN};

get_instance_id(str);

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

        if (instance_id < 0)
                return -EIO;

        /* need to use specific instance_id and guid combination to get right data */
        obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
        if (!obj)
                return -EIO;
        if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < STR_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_str_input() - Validate input of current_value against min and max lengths
 * @instance_id: The instance on which input is validated
 * @buf: Input value
 */
static int validate_str_input(int instance_id, const char *buf)
{
        int in_len = strlen(buf);

        if ((in_len < wmi_priv.str_data[instance_id].min_length) ||
                        (in_len > wmi_priv.str_data[instance_id].max_length))
                return -EINVAL;

        return 0;
}

attribute_s_property_show(display_name_language_code, str);
static struct kobj_attribute str_displ_langcode =
                __ATTR_RO(display_name_language_code);

attribute_s_property_show(display_name, str);
static struct kobj_attribute str_displ_name =
                __ATTR_RO(display_name);

attribute_s_property_show(default_value, str);
static struct kobj_attribute str_default_val =
                __ATTR_RO(default_value);

attribute_property_store(current_value, str);
static struct kobj_attribute str_current_val =
                __ATTR_RW_MODE(current_value, 0600);

attribute_s_property_show(dell_modifier, str);
static struct kobj_attribute str_modifier =
                __ATTR_RO(dell_modifier);

attribute_n_property_show(min_length, str);
static struct kobj_attribute str_min_length =
                __ATTR_RO(min_length);

attribute_n_property_show(max_length, str);
static struct kobj_attribute str_max_length =
                __ATTR_RO(max_length);

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

static struct attribute *str_attrs[] = {
        &str_displ_langcode.attr,
        &str_displ_name.attr,
        &str_default_val.attr,
        &str_current_val.attr,
        &str_modifier.attr,
        &str_min_length.attr,
        &str_max_length.attr,
        &str_type.attr,
        NULL,
};

static const struct attribute_group str_attr_group = {
        .attrs = str_attrs,
};

int alloc_str_data(void)
{
        int ret = 0;

        wmi_priv.str_instances_count = get_instance_count(DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
        wmi_priv.str_data = kzalloc_objs(struct str_data,
                                         wmi_priv.str_instances_count);
        if (!wmi_priv.str_data) {
                wmi_priv.str_instances_count = 0;
                ret = -ENOMEM;
        }
        return ret;
}

/**
 * populate_str_data() - Populate all properties of an instance under string attribute
 * @str_obj: ACPI object with string data
 * @instance_id: The instance to enumerate
 * @attr_name_kobj: The parent kernel object
 */
int populate_str_data(union acpi_object *str_obj, int instance_id, struct kobject *attr_name_kobj)
{
        wmi_priv.str_data[instance_id].attr_name_kobj = attr_name_kobj;
        if (check_property_type(str, ATTR_NAME, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.str_data[instance_id].attribute_name,
                     str_obj[ATTR_NAME].string.pointer);
        if (check_property_type(str, DISPL_NAME_LANG_CODE, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.str_data[instance_id].display_name_language_code,
                     str_obj[DISPL_NAME_LANG_CODE].string.pointer);
        if (check_property_type(str, DISPLAY_NAME, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.str_data[instance_id].display_name,
                     str_obj[DISPLAY_NAME].string.pointer);
        if (check_property_type(str, DEFAULT_VAL, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.str_data[instance_id].default_value,
                     str_obj[DEFAULT_VAL].string.pointer);
        if (check_property_type(str, MODIFIER, ACPI_TYPE_STRING))
                return -EINVAL;
        strlcpy_attr(wmi_priv.str_data[instance_id].dell_modifier,
                     str_obj[MODIFIER].string.pointer);
        if (check_property_type(str, MIN_LEN, ACPI_TYPE_INTEGER))
                return -EINVAL;
        wmi_priv.str_data[instance_id].min_length = (uintptr_t)str_obj[MIN_LEN].string.pointer;
        if (check_property_type(str, MAX_LEN, ACPI_TYPE_INTEGER))
                return -EINVAL;
        wmi_priv.str_data[instance_id].max_length = (uintptr_t) str_obj[MAX_LEN].string.pointer;

        return sysfs_create_group(attr_name_kobj, &str_attr_group);
}

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

        for (instance_id = 0; instance_id < wmi_priv.str_instances_count; instance_id++) {
                if (wmi_priv.str_data[instance_id].attr_name_kobj)
                        sysfs_remove_group(wmi_priv.str_data[instance_id].attr_name_kobj,
                                                                &str_attr_group);
        }
        wmi_priv.str_instances_count = 0;

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