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 11 enum string_properties {MIN_LEN = 6, MAX_LEN}; 12 13 get_instance_id(str); 14 15 static 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->type != ACPI_TYPE_PACKAGE || obj->package.count < STR_MIN_ELEMENTS || 29 obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) { 30 kfree(obj); 31 return -EIO; 32 } 33 ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer); 34 kfree(obj); 35 return ret; 36 } 37 38 /** 39 * validate_str_input() - Validate input of current_value against min and max lengths 40 * @instance_id: The instance on which input is validated 41 * @buf: Input value 42 */ 43 static int validate_str_input(int instance_id, const char *buf) 44 { 45 int in_len = strlen(buf); 46 47 if ((in_len < wmi_priv.str_data[instance_id].min_length) || 48 (in_len > wmi_priv.str_data[instance_id].max_length)) 49 return -EINVAL; 50 51 return 0; 52 } 53 54 attribute_s_property_show(display_name_language_code, str); 55 static struct kobj_attribute str_displ_langcode = 56 __ATTR_RO(display_name_language_code); 57 58 attribute_s_property_show(display_name, str); 59 static struct kobj_attribute str_displ_name = 60 __ATTR_RO(display_name); 61 62 attribute_s_property_show(default_value, str); 63 static struct kobj_attribute str_default_val = 64 __ATTR_RO(default_value); 65 66 attribute_property_store(current_value, str); 67 static struct kobj_attribute str_current_val = 68 __ATTR_RW_MODE(current_value, 0600); 69 70 attribute_s_property_show(dell_modifier, str); 71 static struct kobj_attribute str_modifier = 72 __ATTR_RO(dell_modifier); 73 74 attribute_n_property_show(min_length, str); 75 static struct kobj_attribute str_min_length = 76 __ATTR_RO(min_length); 77 78 attribute_n_property_show(max_length, str); 79 static struct kobj_attribute str_max_length = 80 __ATTR_RO(max_length); 81 82 static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, 83 char *buf) 84 { 85 return sprintf(buf, "string\n"); 86 } 87 static struct kobj_attribute str_type = 88 __ATTR_RO(type); 89 90 static struct attribute *str_attrs[] = { 91 &str_displ_langcode.attr, 92 &str_displ_name.attr, 93 &str_default_val.attr, 94 &str_current_val.attr, 95 &str_modifier.attr, 96 &str_min_length.attr, 97 &str_max_length.attr, 98 &str_type.attr, 99 NULL, 100 }; 101 102 static const struct attribute_group str_attr_group = { 103 .attrs = str_attrs, 104 }; 105 106 int alloc_str_data(void) 107 { 108 int ret = 0; 109 110 wmi_priv.str_instances_count = get_instance_count(DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID); 111 wmi_priv.str_data = kcalloc(wmi_priv.str_instances_count, 112 sizeof(struct str_data), GFP_KERNEL); 113 if (!wmi_priv.str_data) { 114 wmi_priv.str_instances_count = 0; 115 ret = -ENOMEM; 116 } 117 return ret; 118 } 119 120 /** 121 * populate_str_data() - Populate all properties of an instance under string attribute 122 * @str_obj: ACPI object with string data 123 * @instance_id: The instance to enumerate 124 * @attr_name_kobj: The parent kernel object 125 */ 126 int populate_str_data(union acpi_object *str_obj, int instance_id, struct kobject *attr_name_kobj) 127 { 128 wmi_priv.str_data[instance_id].attr_name_kobj = attr_name_kobj; 129 if (check_property_type(str, ATTR_NAME, ACPI_TYPE_STRING)) 130 return -EINVAL; 131 strlcpy_attr(wmi_priv.str_data[instance_id].attribute_name, 132 str_obj[ATTR_NAME].string.pointer); 133 if (check_property_type(str, DISPL_NAME_LANG_CODE, ACPI_TYPE_STRING)) 134 return -EINVAL; 135 strlcpy_attr(wmi_priv.str_data[instance_id].display_name_language_code, 136 str_obj[DISPL_NAME_LANG_CODE].string.pointer); 137 if (check_property_type(str, DISPLAY_NAME, ACPI_TYPE_STRING)) 138 return -EINVAL; 139 strlcpy_attr(wmi_priv.str_data[instance_id].display_name, 140 str_obj[DISPLAY_NAME].string.pointer); 141 if (check_property_type(str, DEFAULT_VAL, ACPI_TYPE_STRING)) 142 return -EINVAL; 143 strlcpy_attr(wmi_priv.str_data[instance_id].default_value, 144 str_obj[DEFAULT_VAL].string.pointer); 145 if (check_property_type(str, MODIFIER, ACPI_TYPE_STRING)) 146 return -EINVAL; 147 strlcpy_attr(wmi_priv.str_data[instance_id].dell_modifier, 148 str_obj[MODIFIER].string.pointer); 149 if (check_property_type(str, MIN_LEN, ACPI_TYPE_INTEGER)) 150 return -EINVAL; 151 wmi_priv.str_data[instance_id].min_length = (uintptr_t)str_obj[MIN_LEN].string.pointer; 152 if (check_property_type(str, MAX_LEN, ACPI_TYPE_INTEGER)) 153 return -EINVAL; 154 wmi_priv.str_data[instance_id].max_length = (uintptr_t) str_obj[MAX_LEN].string.pointer; 155 156 return sysfs_create_group(attr_name_kobj, &str_attr_group); 157 } 158 159 /** 160 * exit_str_attributes() - Clear all attribute data 161 * 162 * Clears all data allocated for this group of attributes 163 */ 164 void exit_str_attributes(void) 165 { 166 int instance_id; 167 168 for (instance_id = 0; instance_id < wmi_priv.str_instances_count; instance_id++) { 169 if (wmi_priv.str_data[instance_id].attr_name_kobj) 170 sysfs_remove_group(wmi_priv.str_data[instance_id].attr_name_kobj, 171 &str_attr_group); 172 } 173 wmi_priv.str_instances_count = 0; 174 175 kfree(wmi_priv.str_data); 176 wmi_priv.str_data = NULL; 177 } 178