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         dev->physical_location->panel = pld->panel;
  28         dev->physical_location->vertical_position = pld->vertical_position;
  29         dev->physical_location->horizontal_position = pld->horizontal_position;
  30         dev->physical_location->dock = pld->dock;
  31         dev->physical_location->lid = pld->lid;
  32
  33         return true;
  34 }
  35
  36 static ssize_t panel_show(struct device *dev, struct device_attribute *attr,
  37         char *buf)
  38 {
  39         const char *panel;
  40
  41         switch (dev->physical_location->panel) {
  42         case DEVICE_PANEL_TOP:
  43                 panel = "top";
  44                 break;
  45         case DEVICE_PANEL_BOTTOM:
  46                 panel = "bottom";
  47                 break;
  48         case DEVICE_PANEL_LEFT:
  49                 panel = "left";
  50                 break;
  51         case DEVICE_PANEL_RIGHT:
  52                 panel = "right";
  53                 break;
  54         case DEVICE_PANEL_FRONT:
  55                 panel = "front";
  56                 break;
  57         default:
  58                 panel = "unknown";
  59         }
  60         return sysfs_emit(buf, "%s\n", panel);
  61 }
  62 static DEVICE_ATTR_RO(panel);
  63
  64 static ssize_t vertical_position_show(struct device *dev,
  65         struct device_attribute *attr, char *buf)
  66 {
  67         const char *vertical_position;
  68
  69         switch (dev->physical_location->vertical_position) {
  70         case DEVICE_VERT_POS_UPPER:
  71                 vertical_position = "upper";
  72                 break;
  73         case DEVICE_VERT_POS_CENTER:
  74                 vertical_position = "center";
  75                 break;
  76         case DEVICE_VERT_POS_LOWER:
  77                 vertical_position = "lower";
  78                 break;
  79         default:
  80                 vertical_position = "unknown";
  81         }
  82         return sysfs_emit(buf, "%s\n", vertical_position);
  83 }
  84 static DEVICE_ATTR_RO(vertical_position);
  85
  86 static ssize_t horizontal_position_show(struct device *dev,
  87         struct device_attribute *attr, char *buf)
  88 {
  89         const char *horizontal_position;
  90
  91         switch (dev->physical_location->horizontal_position) {
  92         case DEVICE_HORI_POS_LEFT:
  93                 horizontal_position = "left";
  94                 break;
  95         case DEVICE_HORI_POS_CENTER:
  96                 horizontal_position = "center";
  97                 break;
  98         case DEVICE_HORI_POS_RIGHT:
  99                 horizontal_position = "right";
 100                 break;
 101         default:
 102                 horizontal_position = "unknown";
 103         }
 104         return sysfs_emit(buf, "%s\n", horizontal_position);
 105 }
 106 static DEVICE_ATTR_RO(horizontal_position);
 107
 108 static ssize_t dock_show(struct device *dev, struct device_attribute *attr,
 109         char *buf)
 110 {
 111         return sysfs_emit(buf, "%s\n",
 112                 dev->physical_location->dock ? "yes" : "no");
 113 }
 114 static DEVICE_ATTR_RO(dock);
 115
 116 static ssize_t lid_show(struct device *dev, struct device_attribute *attr,
 117         char *buf)
 118 {
 119         return sysfs_emit(buf, "%s\n",
 120                 dev->physical_location->lid ? "yes" : "no");
 121 }
 122 static DEVICE_ATTR_RO(lid);
 123
 124 static struct attribute *dev_attr_physical_location[] = {
 125         &dev_attr_panel.attr,
 126         &dev_attr_vertical_position.attr,
 127         &dev_attr_horizontal_position.attr,
 128         &dev_attr_dock.attr,
 129         &dev_attr_lid.attr,
 130         NULL,
 131 };
 132
 133 const struct attribute_group dev_attr_physical_location_group = {
 134         .name = "physical_location",
 135         .attrs = dev_attr_physical_location,
 136 };
 137