drivers/base/physical_location.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Device physical location support
   4  *
   5  * Author: Won Chung <wonchung@google.com>
   6  */
   7
   8 #include <linux/acpi.h>
   9 #include <linux/sysfs.h>
  10
  11 #include "physical_location.h"
  12
  13 bool dev_add_physical_location(struct device *dev)
  14 {
  15         struct acpi_pld_info *pld;
  16         acpi_status status;
  17
  18         if (!has_acpi_companion(dev))
  19                 return false;
  20
  21         status = acpi_get_physical_device_location(ACPI_HANDLE(dev), &pld);
  22         if (ACPI_FAILURE(status))
  23                 return false;
  24
  25         dev->physical_location =
  26                 kzalloc(sizeof(*dev->physical_location), GFP_KERNEL);
  27         if (!dev->physical_location)
  28                 return false;
  29         dev->physical_location->panel = pld->panel;
  30         dev->physical_location->vertical_position = pld->vertical_position;
  31         dev->physical_location->horizontal_position = pld->horizontal_position;
  32         dev->physical_location->dock = pld->dock;
  33         dev->physical_location->lid = pld->lid;
  34
  35         ACPI_FREE(pld);
  36         return true;
  37 }
  38
  39 static ssize_t panel_show(struct device *dev, struct device_attribute *attr,
  40         char *buf)
  41 {
  42         const char *panel;
  43
  44         switch (dev->physical_location->panel) {
  45         case DEVICE_PANEL_TOP:
  46                 panel = "top";
  47                 break;
  48         case DEVICE_PANEL_BOTTOM:
  49                 panel = "bottom";
  50                 break;
  51         case DEVICE_PANEL_LEFT:
  52                 panel = "left";
  53                 break;
  54         case DEVICE_PANEL_RIGHT:
  55                 panel = "right";
  56                 break;
  57         case DEVICE_PANEL_FRONT:
  58                 panel = "front";
  59                 break;
  60         case DEVICE_PANEL_BACK:
  61                 panel = "back";
  62                 break;
  63         default:
  64                 panel = "unknown";
  65         }
  66         return sysfs_emit(buf, "%s\n", panel);
  67 }
  68 static DEVICE_ATTR_RO(panel);
  69
  70 static ssize_t vertical_position_show(struct device *dev,
  71         struct device_attribute *attr, char *buf)
  72 {
  73         const char *vertical_position;
  74
  75         switch (dev->physical_location->vertical_position) {
  76         case DEVICE_VERT_POS_UPPER:
  77                 vertical_position = "upper";
  78                 break;
  79         case DEVICE_VERT_POS_CENTER:
  80                 vertical_position = "center";
  81                 break;
  82         case DEVICE_VERT_POS_LOWER:
  83                 vertical_position = "lower";
  84                 break;
  85         default:
  86                 vertical_position = "unknown";
  87         }
  88         return sysfs_emit(buf, "%s\n", vertical_position);
  89 }
  90 static DEVICE_ATTR_RO(vertical_position);
  91
  92 static ssize_t horizontal_position_show(struct device *dev,
  93         struct device_attribute *attr, char *buf)
  94 {
  95         const char *horizontal_position;
  96
  97         switch (dev->physical_location->horizontal_position) {
  98         case DEVICE_HORI_POS_LEFT:
  99                 horizontal_position = "left";
 100                 break;
 101         case DEVICE_HORI_POS_CENTER:
 102                 horizontal_position = "center";
 103                 break;
 104         case DEVICE_HORI_POS_RIGHT:
 105                 horizontal_position = "right";
 106                 break;
 107         default:
 108                 horizontal_position = "unknown";
 109         }
 110         return sysfs_emit(buf, "%s\n", horizontal_position);
 111 }
 112 static DEVICE_ATTR_RO(horizontal_position);
 113
 114 static ssize_t dock_show(struct device *dev, struct device_attribute *attr,
 115         char *buf)
 116 {
 117         return sysfs_emit(buf, "%s\n",
 118                 dev->physical_location->dock ? "yes" : "no");
 119 }
 120 static DEVICE_ATTR_RO(dock);
 121
 122 static ssize_t lid_show(struct device *dev, struct device_attribute *attr,
 123         char *buf)
 124 {
 125         return sysfs_emit(buf, "%s\n",
 126                 dev->physical_location->lid ? "yes" : "no");
 127 }
 128 static DEVICE_ATTR_RO(lid);
 129
 130 static struct attribute *dev_attr_physical_location[] = {
 131         &dev_attr_panel.attr,
 132         &dev_attr_vertical_position.attr,
 133         &dev_attr_horizontal_position.attr,
 134         &dev_attr_dock.attr,
 135         &dev_attr_lid.attr,
 136         NULL,
 137 };
 138
 139 const struct attribute_group dev_attr_physical_location_group = {
 140         .name = "physical_location",
 141         .attrs = dev_attr_physical_location,
 142 };
 143