1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Functions corresponding to enumeration type attributes under
4  * BIOS Enumeration GUID for use with dell-wmi-sysman
5  *
6  *  Copyright (c) 2020 Dell Inc.
7  */
8 
9 #include "dell-wmi-sysman.h"
10 
11 get_instance_id(enumeration);
12 
current_value_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)13 static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
14 {
15 	int instance_id = get_enumeration_instance_id(kobj);
16 	union acpi_object *obj;
17 	ssize_t ret;
18 
19 	if (instance_id < 0)
20 		return instance_id;
21 
22 	/* need to use specific instance_id and guid combination to get right data */
23 	obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
24 	if (!obj)
25 		return -EIO;
26 	if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) {
27 		kfree(obj);
28 		return -EINVAL;
29 	}
30 	ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer);
31 	kfree(obj);
32 	return ret;
33 }
34 
35 /**
36  * validate_enumeration_input() - Validate input of current_value against possible values
37  * @instance_id: The instance on which input is validated
38  * @buf: Input value
39  */
validate_enumeration_input(int instance_id,const char * buf)40 static int validate_enumeration_input(int instance_id, const char *buf)
41 {
42 	char *options, *tmp, *p;
43 	int ret = -EINVAL;
44 
45 	options = tmp = kstrdup(wmi_priv.enumeration_data[instance_id].possible_values,
46 				 GFP_KERNEL);
47 	if (!options)
48 		return -ENOMEM;
49 
50 	while ((p = strsep(&options, ";")) != NULL) {
51 		if (!*p)
52 			continue;
53 		if (!strcasecmp(p, buf)) {
54 			ret = 0;
55 			break;
56 		}
57 	}
58 
59 	kfree(tmp);
60 	return ret;
61 }
62 
63 attribute_s_property_show(display_name_language_code, enumeration);
64 static struct kobj_attribute displ_langcode =
65 		__ATTR_RO(display_name_language_code);
66 
67 attribute_s_property_show(display_name, enumeration);
68 static struct kobj_attribute displ_name =
69 		__ATTR_RO(display_name);
70 
71 attribute_s_property_show(default_value, enumeration);
72 static struct kobj_attribute default_val =
73 		__ATTR_RO(default_value);
74 
75 attribute_property_store(current_value, enumeration);
76 static struct kobj_attribute current_val =
77 		__ATTR_RW_MODE(current_value, 0600);
78 
79 attribute_s_property_show(dell_modifier, enumeration);
80 static struct kobj_attribute modifier =
81 		__ATTR_RO(dell_modifier);
82 
83 attribute_s_property_show(dell_value_modifier, enumeration);
84 static struct kobj_attribute value_modfr =
85 		__ATTR_RO(dell_value_modifier);
86 
87 attribute_s_property_show(possible_values, enumeration);
88 static struct kobj_attribute poss_val =
89 		__ATTR_RO(possible_values);
90 
type_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)91 static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
92 			 char *buf)
93 {
94 	return sprintf(buf, "enumeration\n");
95 }
96 static struct kobj_attribute type =
97 		__ATTR_RO(type);
98 
99 static struct attribute *enumeration_attrs[] = {
100 	&displ_langcode.attr,
101 	&displ_name.attr,
102 	&default_val.attr,
103 	&current_val.attr,
104 	&modifier.attr,
105 	&value_modfr.attr,
106 	&poss_val.attr,
107 	&type.attr,
108 	NULL,
109 };
110 
111 static const struct attribute_group enumeration_attr_group = {
112 	.attrs = enumeration_attrs,
113 };
114 
alloc_enum_data(void)115 int alloc_enum_data(void)
116 {
117 	int ret = 0;
118 
119 	wmi_priv.enumeration_instances_count =
120 		get_instance_count(DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID);
121 	wmi_priv.enumeration_data = kcalloc(wmi_priv.enumeration_instances_count,
122 					sizeof(struct enumeration_data), GFP_KERNEL);
123 	if (!wmi_priv.enumeration_data) {
124 		wmi_priv.enumeration_instances_count = 0;
125 		ret = -ENOMEM;
126 	}
127 	return ret;
128 }
129 
130 /**
131  * populate_enum_data() - Populate all properties of an instance under enumeration attribute
132  * @enumeration_obj: ACPI object with enumeration data
133  * @instance_id: The instance to enumerate
134  * @attr_name_kobj: The parent kernel object
135  * @enum_property_count: Total properties count under enumeration type
136  */
populate_enum_data(union acpi_object * enumeration_obj,int instance_id,struct kobject * attr_name_kobj,u32 enum_property_count)137 int populate_enum_data(union acpi_object *enumeration_obj, int instance_id,
138 			struct kobject *attr_name_kobj, u32 enum_property_count)
139 {
140 	int i, next_obj, value_modifier_count, possible_values_count;
141 
142 	wmi_priv.enumeration_data[instance_id].attr_name_kobj = attr_name_kobj;
143 	if (check_property_type(enumeration, ATTR_NAME, ACPI_TYPE_STRING))
144 		return -EINVAL;
145 	strlcpy_attr(wmi_priv.enumeration_data[instance_id].attribute_name,
146 		enumeration_obj[ATTR_NAME].string.pointer);
147 	if (check_property_type(enumeration, DISPL_NAME_LANG_CODE, ACPI_TYPE_STRING))
148 		return -EINVAL;
149 	strlcpy_attr(wmi_priv.enumeration_data[instance_id].display_name_language_code,
150 		enumeration_obj[DISPL_NAME_LANG_CODE].string.pointer);
151 	if (check_property_type(enumeration, DISPLAY_NAME, ACPI_TYPE_STRING))
152 		return -EINVAL;
153 	strlcpy_attr(wmi_priv.enumeration_data[instance_id].display_name,
154 		enumeration_obj[DISPLAY_NAME].string.pointer);
155 	if (check_property_type(enumeration, DEFAULT_VAL, ACPI_TYPE_STRING))
156 		return -EINVAL;
157 	strlcpy_attr(wmi_priv.enumeration_data[instance_id].default_value,
158 		enumeration_obj[DEFAULT_VAL].string.pointer);
159 	if (check_property_type(enumeration, MODIFIER, ACPI_TYPE_STRING))
160 		return -EINVAL;
161 	strlcpy_attr(wmi_priv.enumeration_data[instance_id].dell_modifier,
162 		enumeration_obj[MODIFIER].string.pointer);
163 
164 	next_obj = MODIFIER + 1;
165 
166 	if (next_obj >= enum_property_count)
167 		return -EINVAL;
168 
169 	if (check_property_type(enumeration, next_obj, ACPI_TYPE_INTEGER))
170 		return -EINVAL;
171 	value_modifier_count = (uintptr_t)enumeration_obj[next_obj++].string.pointer;
172 
173 	for (i = 0; i < value_modifier_count; i++) {
174 		if (next_obj >= enum_property_count)
175 			return -EINVAL;
176 		if (check_property_type(enumeration, next_obj, ACPI_TYPE_STRING))
177 			return -EINVAL;
178 		strcat(wmi_priv.enumeration_data[instance_id].dell_value_modifier,
179 			enumeration_obj[next_obj++].string.pointer);
180 		strcat(wmi_priv.enumeration_data[instance_id].dell_value_modifier, ";");
181 	}
182 
183 	if (next_obj >= enum_property_count)
184 		return -EINVAL;
185 
186 	if (check_property_type(enumeration, next_obj, ACPI_TYPE_INTEGER))
187 		return -EINVAL;
188 	possible_values_count = (uintptr_t) enumeration_obj[next_obj++].string.pointer;
189 
190 	for (i = 0; i < possible_values_count; i++) {
191 		if (next_obj >= enum_property_count)
192 			return -EINVAL;
193 		if (check_property_type(enumeration, next_obj, ACPI_TYPE_STRING))
194 			return -EINVAL;
195 		strcat(wmi_priv.enumeration_data[instance_id].possible_values,
196 			enumeration_obj[next_obj++].string.pointer);
197 		strcat(wmi_priv.enumeration_data[instance_id].possible_values, ";");
198 	}
199 
200 	return sysfs_create_group(attr_name_kobj, &enumeration_attr_group);
201 }
202 
203 /**
204  * exit_enum_attributes() - Clear all attribute data
205  *
206  * Clears all data allocated for this group of attributes
207  */
exit_enum_attributes(void)208 void exit_enum_attributes(void)
209 {
210 	int instance_id;
211 
212 	for (instance_id = 0; instance_id < wmi_priv.enumeration_instances_count; instance_id++) {
213 		if (wmi_priv.enumeration_data[instance_id].attr_name_kobj)
214 			sysfs_remove_group(wmi_priv.enumeration_data[instance_id].attr_name_kobj,
215 								&enumeration_attr_group);
216 	}
217 	wmi_priv.enumeration_instances_count = 0;
218 
219 	kfree(wmi_priv.enumeration_data);
220 	wmi_priv.enumeration_data = NULL;
221 }
222