drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c

   1 /*
   2  * inv_mpu_acpi: ACPI processing for creating client devices
   3  * Copyright (c) 2015, 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 #ifdef CONFIG_ACPI
  16
  17 #include <linux/kernel.h>
  18 #include <linux/i2c.h>
  19 #include <linux/dmi.h>
  20 #include <linux/acpi.h>
  21 #include "inv_mpu_iio.h"
  22
  23 enum inv_mpu_product_name {
  24         INV_MPU_NOT_MATCHED,
  25         INV_MPU_ASUS_T100TA,
  26 };
  27
  28 static enum inv_mpu_product_name matched_product_name;
  29
  30 static int __init asus_t100_matched(const struct dmi_system_id *d)
  31 {
  32         matched_product_name = INV_MPU_ASUS_T100TA;
  33
  34         return 0;
  35 }
  36
  37 static const struct dmi_system_id inv_mpu_dev_list[] = {
  38         {
  39         .callback = asus_t100_matched,
  40         .ident = "Asus Transformer Book T100",
  41                 .matches = {
  42                         DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC"),
  43                         DMI_MATCH(DMI_PRODUCT_NAME, "T100TA"),
  44                         DMI_MATCH(DMI_PRODUCT_VERSION, "1.0"),
  45                 },
  46         },
  47         /* Add more matching tables here..*/
  48         {}
  49 };
  50
  51 static int asus_acpi_get_sensor_info(struct acpi_device *adev,
  52                                      struct i2c_client *client,
  53                                      struct i2c_board_info *info)
  54 {
  55         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
  56         int i;
  57         acpi_status status;
  58         union acpi_object *cpm;
  59         int ret;
  60
  61         status = acpi_evaluate_object(adev->handle, "CNF0", NULL, &buffer);
  62         if (ACPI_FAILURE(status))
  63                 return -ENODEV;
  64
  65         cpm = buffer.pointer;
  66         for (i = 0; i < cpm->package.count; ++i) {
  67                 union acpi_object *elem;
  68                 int j;
  69
  70                 elem = &cpm->package.elements[i];
  71                 for (j = 0; j < elem->package.count; ++j) {
  72                         union acpi_object *sub_elem;
  73
  74                         sub_elem = &elem->package.elements[j];
  75                         if (sub_elem->type == ACPI_TYPE_STRING)
  76                                 strlcpy(info->type, sub_elem->string.pointer,
  77                                         sizeof(info->type));
  78                         else if (sub_elem->type == ACPI_TYPE_INTEGER) {
  79                                 if (sub_elem->integer.value != client->addr) {
  80                                         info->addr = sub_elem->integer.value;
  81                                         break; /* Not a MPU6500 primary */
  82                                 }
  83                         }
  84                 }
  85         }
  86         ret = cpm->package.count;
  87         kfree(buffer.pointer);
  88
  89         return ret;
  90 }
  91
  92 static int acpi_i2c_check_resource(struct acpi_resource *ares, void *data)
  93 {
  94         struct acpi_resource_i2c_serialbus *sb;
  95         u32 *addr = data;
  96
  97         if (i2c_acpi_get_i2c_resource(ares, &sb)) {
  98                 if (*addr)
  99                         *addr |= (sb->slave_address << 16);
 100                 else
 101                         *addr = sb->slave_address;
 102         }
 103
 104         /* Tell the ACPI core that we already copied this address */
 105         return 1;
 106 }
 107
 108 static int inv_mpu_process_acpi_config(struct i2c_client *client,
 109                                        unsigned short *primary_addr,
 110                                        unsigned short *secondary_addr)
 111 {
 112         const struct acpi_device_id *id;
 113         struct acpi_device *adev;
 114         u32 i2c_addr = 0;
 115         LIST_HEAD(resources);
 116         int ret;
 117
 118         id = acpi_match_device(client->dev.driver->acpi_match_table,
 119                                &client->dev);
 120         if (!id)
 121                 return -ENODEV;
 122
 123         adev = ACPI_COMPANION(&client->dev);
 124         if (!adev)
 125                 return -ENODEV;
 126
 127         ret = acpi_dev_get_resources(adev, &resources,
 128                                      acpi_i2c_check_resource, &i2c_addr);
 129         if (ret < 0)
 130                 return ret;
 131
 132         acpi_dev_free_resource_list(&resources);
 133         *primary_addr = i2c_addr & 0x0000ffff;
 134         *secondary_addr = (i2c_addr & 0xffff0000) >> 16;
 135
 136         return 0;
 137 }
 138
 139 int inv_mpu_acpi_create_mux_client(struct i2c_client *client)
 140 {
 141         struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(&client->dev));
 142
 143         st->mux_client = NULL;
 144         if (ACPI_HANDLE(&client->dev)) {
 145                 struct i2c_board_info info;
 146                 struct acpi_device *adev;
 147                 int ret = -1;
 148
 149                 adev = ACPI_COMPANION(&client->dev);
 150                 memset(&info, 0, sizeof(info));
 151
 152                 dmi_check_system(inv_mpu_dev_list);
 153                 switch (matched_product_name) {
 154                 case INV_MPU_ASUS_T100TA:
 155                         ret = asus_acpi_get_sensor_info(adev, client,
 156                                                         &info);
 157                         break;
 158                 /* Add more matched product processing here */
 159                 default:
 160                         break;
 161                 }
 162
 163                 if (ret < 0) {
 164                         /* No matching DMI, so create device on INV6XX type */
 165                         unsigned short primary, secondary;
 166
 167                         ret = inv_mpu_process_acpi_config(client, &primary,
 168                                                           &secondary);
 169                         if (!ret && secondary) {
 170                                 char *name;
 171
 172                                 info.addr = secondary;
 173                                 strlcpy(info.type, dev_name(&adev->dev),
 174                                         sizeof(info.type));
 175                                 name = strchr(info.type, ':');
 176                                 if (name)
 177                                         *name = '\0';
 178                                 strlcat(info.type, "-client",
 179                                         sizeof(info.type));
 180                         } else
 181                                 return 0; /* no secondary addr, which is OK */
 182                 }
 183                 st->mux_client = i2c_new_device(st->muxc->adapter[0], &info);
 184                 if (!st->mux_client)
 185                         return -ENODEV;
 186         }
 187
 188         return 0;
 189 }
 190
 191 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client)
 192 {
 193         struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(&client->dev));
 194
 195         i2c_unregister_device(st->mux_client);
 196 }
 197 #else
 198
 199 #include "inv_mpu_iio.h"
 200
 201 int inv_mpu_acpi_create_mux_client(struct i2c_client *client)
 202 {
 203         return 0;
 204 }
 205
 206 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client)
 207 {
 208 }
 209 #endif