drivers/platform/x86/dell-wmi-sysman/int-attributes.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Functions corresponding to integer type attributes under BIOS Integer 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 int_properties {MIN_VALUE = 6, MAX_VALUE, SCALAR_INCR};
  12
  13 get_instance_id(integer);
  14
  15 static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
  16 {
  17         int instance_id = get_integer_instance_id(kobj);
  18         union acpi_object *obj;
  19         ssize_t ret;
  20
  21         if (instance_id < 0)
  22                 return instance_id;
  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_INTEGER_ATTRIBUTE_GUID);
  26         if (!obj)
  27                 return -EIO;
  28         if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_INTEGER) {
  29                 kfree(obj);
  30                 return -EINVAL;
  31         }
  32         ret = snprintf(buf, PAGE_SIZE, "%lld\n", obj->package.elements[CURRENT_VAL].integer.value);
  33         kfree(obj);
  34         return ret;
  35 }
  36
  37 /**
  38  * validate_integer_input() - Validate input of current_value against lower and upper bound
  39  * @instance_id: The instance on which input is validated
  40  * @buf: Input value
  41  */
  42 static int validate_integer_input(int instance_id, char *buf)
  43 {
  44         int in_val;
  45         int ret;
  46
  47         ret = kstrtoint(buf, 0, &in_val);
  48         if (ret)
  49                 return ret;
  50         if (in_val < wmi_priv.integer_data[instance_id].min_value ||
  51                         in_val > wmi_priv.integer_data[instance_id].max_value)
  52                 return -EINVAL;
  53
  54         /* workaround for BIOS error.
  55          * validate input to avoid setting 0 when integer input passed with + sign
  56          */
  57         if (*buf == '+')
  58                 memmove(buf, (buf + 1), strlen(buf + 1) + 1);
  59
  60         return ret;
  61 }
  62
  63 attribute_s_property_show(display_name_language_code, integer);
  64 static struct kobj_attribute integer_displ_langcode =
  65         __ATTR_RO(display_name_language_code);
  66
  67 attribute_s_property_show(display_name, integer);
  68 static struct kobj_attribute integer_displ_name =
  69         __ATTR_RO(display_name);
  70
  71 attribute_n_property_show(default_value, integer);
  72 static struct kobj_attribute integer_default_val =
  73         __ATTR_RO(default_value);
  74
  75 attribute_property_store(current_value, integer);
  76 static struct kobj_attribute integer_current_val =
  77         __ATTR_RW_MODE(current_value, 0600);
  78
  79 attribute_s_property_show(dell_modifier, integer);
  80 static struct kobj_attribute integer_modifier =
  81         __ATTR_RO(dell_modifier);
  82
  83 attribute_n_property_show(min_value, integer);
  84 static struct kobj_attribute integer_lower_bound =
  85         __ATTR_RO(min_value);
  86
  87 attribute_n_property_show(max_value, integer);
  88 static struct kobj_attribute integer_upper_bound =
  89         __ATTR_RO(max_value);
  90
  91 attribute_n_property_show(scalar_increment, integer);
  92 static struct kobj_attribute integer_scalar_increment =
  93         __ATTR_RO(scalar_increment);
  94
  95 static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr,
  96                          char *buf)
  97 {
  98         return sprintf(buf, "integer\n");
  99 }
 100 static struct kobj_attribute integer_type =
 101         __ATTR_RO(type);
 102
 103 static struct attribute *integer_attrs[] = {
 104         &integer_displ_langcode.attr,
 105         &integer_displ_name.attr,
 106         &integer_default_val.attr,
 107         &integer_current_val.attr,
 108         &integer_modifier.attr,
 109         &integer_lower_bound.attr,
 110         &integer_upper_bound.attr,
 111         &integer_scalar_increment.attr,
 112         &integer_type.attr,
 113         NULL,
 114 };
 115
 116 static const struct attribute_group integer_attr_group = {
 117         .attrs = integer_attrs,
 118 };
 119
 120 int alloc_int_data(void)
 121 {
 122         int ret = 0;
 123
 124         wmi_priv.integer_instances_count = get_instance_count(DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID);
 125         wmi_priv.integer_data = kcalloc(wmi_priv.integer_instances_count,
 126                                         sizeof(struct integer_data), GFP_KERNEL);
 127         if (!wmi_priv.integer_data) {
 128                 wmi_priv.integer_instances_count = 0;
 129                 ret = -ENOMEM;
 130         }
 131         return ret;
 132 }
 133
 134 /**
 135  * populate_int_data() - Populate all properties of an instance under integer attribute
 136  * @integer_obj: ACPI object with integer data
 137  * @instance_id: The instance to enumerate
 138  * @attr_name_kobj: The parent kernel object
 139  */
 140 int populate_int_data(union acpi_object *integer_obj, int instance_id,
 141                         struct kobject *attr_name_kobj)
 142 {
 143         wmi_priv.integer_data[instance_id].attr_name_kobj = attr_name_kobj;
 144         strlcpy_attr(wmi_priv.integer_data[instance_id].attribute_name,
 145                 integer_obj[ATTR_NAME].string.pointer);
 146         strlcpy_attr(wmi_priv.integer_data[instance_id].display_name_language_code,
 147                 integer_obj[DISPL_NAME_LANG_CODE].string.pointer);
 148         strlcpy_attr(wmi_priv.integer_data[instance_id].display_name,
 149                 integer_obj[DISPLAY_NAME].string.pointer);
 150         wmi_priv.integer_data[instance_id].default_value =
 151                 (uintptr_t)integer_obj[DEFAULT_VAL].string.pointer;
 152         strlcpy_attr(wmi_priv.integer_data[instance_id].dell_modifier,
 153                 integer_obj[MODIFIER].string.pointer);
 154         wmi_priv.integer_data[instance_id].min_value =
 155                 (uintptr_t)integer_obj[MIN_VALUE].string.pointer;
 156         wmi_priv.integer_data[instance_id].max_value =
 157                 (uintptr_t)integer_obj[MAX_VALUE].string.pointer;
 158         wmi_priv.integer_data[instance_id].scalar_increment =
 159                 (uintptr_t)integer_obj[SCALAR_INCR].string.pointer;
 160
 161         return sysfs_create_group(attr_name_kobj, &integer_attr_group);
 162 }
 163
 164 /**
 165  * exit_int_attributes() - Clear all attribute data
 166  *
 167  * Clears all data allocated for this group of attributes
 168  */
 169 void exit_int_attributes(void)
 170 {
 171         int instance_id;
 172
 173         for (instance_id = 0; instance_id < wmi_priv.integer_instances_count; instance_id++) {
 174                 if (wmi_priv.integer_data[instance_id].attr_name_kobj)
 175                         sysfs_remove_group(wmi_priv.integer_data[instance_id].attr_name_kobj,
 176                                                                 &integer_attr_group);
 177         }
 178         kfree(wmi_priv.integer_data);
 179 }