LXR linux/drivers/platform/x86/dell/dell-wmi-sysman/string-attributes.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Functions corresponding to string type attributes under BIOS String GUID for use with
   4 * dell-wmi-sysman
   5 *
   6 *  Copyright (c) 2020 Dell Inc.
   7 */
   8
   9#include "dell-wmi-sysman.h"
  10
  11enum string_properties {MIN_LEN = 6, MAX_LEN};
  12
  13get_instance_id(str);
  14
  15static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
  16{
  17        int instance_id = get_str_instance_id(kobj);
  18        union acpi_object *obj;
  19        ssize_t ret;
  20
  21        if (instance_id < 0)
  22                return -EIO;
  23
  24        /* need to use specific instance_id and guid combination to get right data */
  25        obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
  26        if (!obj)
  27                return -EIO;
  28        if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) {
  29                kfree(obj);
  30                return -EINVAL;
  31        }
  32        ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer);
  33        kfree(obj);
  34        return ret;
  35}
  36
  37/**
  38 * validate_str_input() - Validate input of current_value against min and max lengths
  39 * @instance_id: The instance on which input is validated
  40 * @buf: Input value
  41 */
  42static int validate_str_input(int instance_id, const char *buf)
  43{
  44        int in_len = strlen(buf);
  45
  46        if ((in_len < wmi_priv.str_data[instance_id].min_length) ||
  47                        (in_len > wmi_priv.str_data[instance_id].max_length))
  48                return -EINVAL;
  49
  50        return 0;
  51}
  52
  53attribute_s_property_show(display_name_language_code, str);
  54static struct kobj_attribute str_displ_langcode =
  55                __ATTR_RO(display_name_language_code);
  56
  57attribute_s_property_show(display_name, str);
  58static struct kobj_attribute str_displ_name =
  59                __ATTR_RO(display_name);
  60
  61attribute_s_property_show(default_value, str);
  62static struct kobj_attribute str_default_val =
  63                __ATTR_RO(default_value);
  64
  65attribute_property_store(current_value, str);
  66static struct kobj_attribute str_current_val =
  67                __ATTR_RW_MODE(current_value, 0600);
  68
  69attribute_s_property_show(dell_modifier, str);
  70static struct kobj_attribute str_modifier =
  71                __ATTR_RO(dell_modifier);
  72
  73attribute_n_property_show(min_length, str);
  74static struct kobj_attribute str_min_length =
  75                __ATTR_RO(min_length);
  76
  77attribute_n_property_show(max_length, str);
  78static struct kobj_attribute str_max_length =
  79                __ATTR_RO(max_length);
  80
  81static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
  82                         char *buf)
  83{
  84        return sprintf(buf, "string\n");
  85}
  86static struct kobj_attribute str_type =
  87        __ATTR_RO(type);
  88
  89static struct attribute *str_attrs[] = {
  90        &str_displ_langcode.attr,
  91        &str_displ_name.attr,
  92        &str_default_val.attr,
  93        &str_current_val.attr,
  94        &str_modifier.attr,
  95        &str_min_length.attr,
  96        &str_max_length.attr,
  97        &str_type.attr,
  98        NULL,
  99};
 100
 101static const struct attribute_group str_attr_group = {
 102        .attrs = str_attrs,
 103};
 104
 105int alloc_str_data(void)
 106{
 107        int ret = 0;
 108
 109        wmi_priv.str_instances_count = get_instance_count(DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID);
 110        wmi_priv.str_data = kcalloc(wmi_priv.str_instances_count,
 111                                        sizeof(struct str_data), GFP_KERNEL);
 112        if (!wmi_priv.str_data) {
 113                wmi_priv.str_instances_count = 0;
 114                ret = -ENOMEM;
 115        }
 116        return ret;
 117}
 118
 119/**
 120 * populate_str_data() - Populate all properties of an instance under string attribute
 121 * @str_obj: ACPI object with string data
 122 * @instance_id: The instance to enumerate
 123 * @attr_name_kobj: The parent kernel object
 124 */
 125int populate_str_data(union acpi_object *str_obj, int instance_id, struct kobject *attr_name_kobj)
 126{
 127        wmi_priv.str_data[instance_id].attr_name_kobj = attr_name_kobj;
 128        if (check_property_type(str, ATTR_NAME, ACPI_TYPE_STRING))
 129                return -EINVAL;
 130        strlcpy_attr(wmi_priv.str_data[instance_id].attribute_name,
 131                     str_obj[ATTR_NAME].string.pointer);
 132        if (check_property_type(str, DISPL_NAME_LANG_CODE, ACPI_TYPE_STRING))
 133                return -EINVAL;
 134        strlcpy_attr(wmi_priv.str_data[instance_id].display_name_language_code,
 135                     str_obj[DISPL_NAME_LANG_CODE].string.pointer);
 136        if (check_property_type(str, DISPLAY_NAME, ACPI_TYPE_STRING))
 137                return -EINVAL;
 138        strlcpy_attr(wmi_priv.str_data[instance_id].display_name,
 139                     str_obj[DISPLAY_NAME].string.pointer);
 140        if (check_property_type(str, DEFAULT_VAL, ACPI_TYPE_STRING))
 141                return -EINVAL;
 142        strlcpy_attr(wmi_priv.str_data[instance_id].default_value,
 143                     str_obj[DEFAULT_VAL].string.pointer);
 144        if (check_property_type(str, MODIFIER, ACPI_TYPE_STRING))
 145                return -EINVAL;
 146        strlcpy_attr(wmi_priv.str_data[instance_id].dell_modifier,
 147                     str_obj[MODIFIER].string.pointer);
 148        if (check_property_type(str, MIN_LEN, ACPI_TYPE_INTEGER))
 149                return -EINVAL;
 150        wmi_priv.str_data[instance_id].min_length = (uintptr_t)str_obj[MIN_LEN].string.pointer;
 151        if (check_property_type(str, MAX_LEN, ACPI_TYPE_INTEGER))
 152                return -EINVAL;
 153        wmi_priv.str_data[instance_id].max_length = (uintptr_t) str_obj[MAX_LEN].string.pointer;
 154
 155        return sysfs_create_group(attr_name_kobj, &str_attr_group);
 156}
 157
 158/**
 159 * exit_str_attributes() - Clear all attribute data
 160 *
 161 * Clears all data allocated for this group of attributes
 162 */
 163void exit_str_attributes(void)
 164{
 165        int instance_id;
 166
 167        for (instance_id = 0; instance_id < wmi_priv.str_instances_count; instance_id++) {
 168                if (wmi_priv.str_data[instance_id].attr_name_kobj)
 169                        sysfs_remove_group(wmi_priv.str_data[instance_id].attr_name_kobj,
 170                                                                &str_attr_group);
 171        }
 172        wmi_priv.str_instances_count = 0;
 173
 174        kfree(wmi_priv.str_data);
 175        wmi_priv.str_data = NULL;
 176}
 177