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->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 */ 42 static 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 53 attribute_s_property_show(display_name_language_code, str); 54 static struct kobj_attribute str_displ_langcode = 55 __ATTR_RO(display_name_language_code); 56 57 attribute_s_property_show(display_name, str); 58 static struct kobj_attribute str_displ_name = 59 __ATTR_RO(display_name); 60 61 attribute_s_property_show(default_value, str); 62 static struct kobj_attribute str_default_val = 63 __ATTR_RO(default_value); 64 65 attribute_property_store(current_value, str); 66 static struct kobj_attribute str_current_val = 67 __ATTR_RW_MODE(current_value, 0600); 68 69 attribute_s_property_show(dell_modifier, str); 70 static struct kobj_attribute str_modifier = 71 __ATTR_RO(dell_modifier); 72 73 attribute_n_property_show(min_length, str); 74 static struct kobj_attribute str_min_length = 75 __ATTR_RO(min_length); 76 77 attribute_n_property_show(max_length, str); 78 static struct kobj_attribute str_max_length = 79 __ATTR_RO(max_length); 80 81 static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, 82 char *buf) 83 { 84 return sprintf(buf, "string\n"); 85 } 86 static struct kobj_attribute str_type = 87 __ATTR_RO(type); 88 89 static 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 }; 100 101 static const struct attribute_group str_attr_group = { 102 .attrs = str_attrs, 103 }; 104 105 int 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 */ 125 int 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 */ 163 void 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