drivers/thermal/int3403_thermal.c

   1 /*
   2  * ACPI INT3403 thermal driver
   3  * Copyright (c) 2013, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/types.h>
  19 #include <linux/acpi.h>
  20 #include <linux/thermal.h>
  21
  22 #define INT3403_TYPE_SENSOR             0x03
  23 #define INT3403_PERF_CHANGED_EVENT      0x80
  24 #define INT3403_THERMAL_EVENT           0x90
  25
  26 #define DECI_KELVIN_TO_MILLI_CELSIUS(t, off) (((t) - (off)) * 100)
  27 #define KELVIN_OFFSET   2732
  28 #define MILLI_CELSIUS_TO_DECI_KELVIN(t, off) (((t) / 100) + (off))
  29
  30 #define ACPI_INT3403_CLASS              "int3403"
  31 #define ACPI_INT3403_FILE_STATE         "state"
  32
  33 struct int3403_sensor {
  34         struct thermal_zone_device *tzone;
  35         unsigned long *thresholds;
  36 };
  37
  38 static int sys_get_curr_temp(struct thermal_zone_device *tzone,
  39                                 unsigned long *temp)
  40 {
  41         struct acpi_device *device = tzone->devdata;
  42         unsigned long long tmp;
  43         acpi_status status;
  44
  45         status = acpi_evaluate_integer(device->handle, "_TMP", NULL, &tmp);
  46         if (ACPI_FAILURE(status))
  47                 return -EIO;
  48
  49         *temp = DECI_KELVIN_TO_MILLI_CELSIUS(tmp, KELVIN_OFFSET);
  50
  51         return 0;
  52 }
  53
  54 static int sys_get_trip_hyst(struct thermal_zone_device *tzone,
  55                 int trip, unsigned long *temp)
  56 {
  57         struct acpi_device *device = tzone->devdata;
  58         unsigned long long hyst;
  59         acpi_status status;
  60
  61         status = acpi_evaluate_integer(device->handle, "GTSH", NULL, &hyst);
  62         if (ACPI_FAILURE(status))
  63                 return -EIO;
  64
  65         /*
  66          * Thermal hysteresis represents a temperature difference.
  67          * Kelvin and Celsius have same degree size. So the
  68          * conversion here between tenths of degree Kelvin unit
  69          * and Milli-Celsius unit is just to multiply 100.
  70          */
  71         *temp = hyst * 100;
  72
  73         return 0;
  74 }
  75
  76 static int sys_get_trip_temp(struct thermal_zone_device *tzone,
  77                 int trip, unsigned long *temp)
  78 {
  79         struct acpi_device *device = tzone->devdata;
  80         struct int3403_sensor *obj = acpi_driver_data(device);
  81
  82         /*
  83          * get_trip_temp is a mandatory callback but
  84          * PATx method doesn't return any value, so return
  85          * cached value, which was last set from user space.
  86          */
  87         *temp = obj->thresholds[trip];
  88
  89         return 0;
  90 }
  91
  92 static int sys_get_trip_type(struct thermal_zone_device *thermal,
  93                 int trip, enum thermal_trip_type *type)
  94 {
  95         /* Mandatory callback, may not mean much here */
  96         *type = THERMAL_TRIP_PASSIVE;
  97
  98         return 0;
  99 }
 100
 101 int sys_set_trip_temp(struct thermal_zone_device *tzone, int trip,
 102                                                         unsigned long temp)
 103 {
 104         struct acpi_device *device = tzone->devdata;
 105         acpi_status status;
 106         char name[10];
 107         int ret = 0;
 108         struct int3403_sensor *obj = acpi_driver_data(device);
 109
 110         snprintf(name, sizeof(name), "PAT%d", trip);
 111         if (acpi_has_method(device->handle, name)) {
 112                 status = acpi_execute_simple_method(device->handle, name,
 113                                 MILLI_CELSIUS_TO_DECI_KELVIN(temp,
 114                                                         KELVIN_OFFSET));
 115                 if (ACPI_FAILURE(status))
 116                         ret = -EIO;
 117                 else
 118                         obj->thresholds[trip] = temp;
 119         } else {
 120                 ret = -EIO;
 121                 dev_err(&device->dev, "sys_set_trip_temp: method not found\n");
 122         }
 123
 124         return ret;
 125 }
 126
 127 static struct thermal_zone_device_ops tzone_ops = {
 128         .get_temp = sys_get_curr_temp,
 129         .get_trip_temp = sys_get_trip_temp,
 130         .get_trip_type = sys_get_trip_type,
 131         .set_trip_temp = sys_set_trip_temp,
 132         .get_trip_hyst =  sys_get_trip_hyst,
 133 };
 134
 135 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
 136 {
 137         struct int3403_sensor *obj;
 138
 139         if (!device)
 140                 return;
 141
 142         obj = acpi_driver_data(device);
 143         if (!obj)
 144                 return;
 145
 146         switch (event) {
 147         case INT3403_PERF_CHANGED_EVENT:
 148                 break;
 149         case INT3403_THERMAL_EVENT:
 150                 thermal_zone_device_update(obj->tzone);
 151                 break;
 152         default:
 153                 dev_err(&device->dev, "Unsupported event [0x%x]\n", event);
 154                 break;
 155         }
 156 }
 157
 158 static int acpi_int3403_add(struct acpi_device *device)
 159 {
 160         int result = 0;
 161         unsigned long long ptyp;
 162         acpi_status status;
 163         struct int3403_sensor *obj;
 164         unsigned long long trip_cnt;
 165         int trip_mask = 0;
 166
 167         if (!device)
 168                 return -EINVAL;
 169
 170         status = acpi_evaluate_integer(device->handle, "PTYP", NULL, &ptyp);
 171         if (ACPI_FAILURE(status))
 172                 return -EINVAL;
 173
 174         if (ptyp != INT3403_TYPE_SENSOR)
 175                 return -EINVAL;
 176
 177         obj = devm_kzalloc(&device->dev, sizeof(*obj), GFP_KERNEL);
 178         if (!obj)
 179                 return -ENOMEM;
 180
 181         device->driver_data = obj;
 182
 183         status = acpi_evaluate_integer(device->handle, "PATC", NULL,
 184                                                 &trip_cnt);
 185         if (ACPI_FAILURE(status))
 186                 trip_cnt = 0;
 187
 188         if (trip_cnt) {
 189                 /* We have to cache, thresholds can't be readback */
 190                 obj->thresholds = devm_kzalloc(&device->dev,
 191                                         sizeof(*obj->thresholds) * trip_cnt,
 192                                         GFP_KERNEL);
 193                 if (!obj->thresholds)
 194                         return -ENOMEM;
 195                 trip_mask = BIT(trip_cnt) - 1;
 196         }
 197         obj->tzone = thermal_zone_device_register(acpi_device_bid(device),
 198                                 trip_cnt, trip_mask, device, &tzone_ops,
 199                                 NULL, 0, 0);
 200         if (IS_ERR(obj->tzone)) {
 201                 result = PTR_ERR(obj->tzone);
 202                 return result;
 203         }
 204
 205         strcpy(acpi_device_name(device), "INT3403");
 206         strcpy(acpi_device_class(device), ACPI_INT3403_CLASS);
 207
 208         return 0;
 209 }
 210
 211 static int acpi_int3403_remove(struct acpi_device *device)
 212 {
 213         struct int3403_sensor *obj;
 214
 215         obj = acpi_driver_data(device);
 216         thermal_zone_device_unregister(obj->tzone);
 217
 218         return 0;
 219 }
 220
 221 ACPI_MODULE_NAME("int3403");
 222 static const struct acpi_device_id int3403_device_ids[] = {
 223         {"INT3403", 0},
 224         {"", 0},
 225 };
 226 MODULE_DEVICE_TABLE(acpi, int3403_device_ids);
 227
 228 static struct acpi_driver acpi_int3403_driver = {
 229         .name = "INT3403",
 230         .class = ACPI_INT3403_CLASS,
 231         .ids = int3403_device_ids,
 232         .ops = {
 233                 .add = acpi_int3403_add,
 234                 .remove = acpi_int3403_remove,
 235                 .notify = acpi_thermal_notify,
 236                 },
 237 };
 238
 239 module_acpi_driver(acpi_int3403_driver);
 240
 241 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 242 MODULE_LICENSE("GPL v2");
 243 MODULE_DESCRIPTION("ACPI INT3403 thermal driver");