drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * inv_mpu_acpi: ACPI processing for creating client devices
   4  * Copyright (c) 2015, Intel Corporation.
   5  */
   6
   7 #ifdef CONFIG_ACPI
   8
   9 #include <linux/kernel.h>
  10 #include <linux/i2c.h>
  11 #include <linux/dmi.h>
  12 #include <linux/acpi.h>
  13 #include "inv_mpu_iio.h"
  14
  15 enum inv_mpu_product_name {
  16         INV_MPU_NOT_MATCHED,
  17         INV_MPU_ASUS_T100TA,
  18 };
  19
  20 static enum inv_mpu_product_name matched_product_name;
  21
  22 static int __init asus_t100_matched(const struct dmi_system_id *d)
  23 {
  24         matched_product_name = INV_MPU_ASUS_T100TA;
  25
  26         return 0;
  27 }
  28
  29 static const struct dmi_system_id inv_mpu_dev_list[] = {
  30         {
  31         .callback = asus_t100_matched,
  32         .ident = "Asus Transformer Book T100",
  33                 .matches = {
  34                         DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC"),
  35                         DMI_MATCH(DMI_PRODUCT_NAME, "T100TA"),
  36                         DMI_MATCH(DMI_PRODUCT_VERSION, "1.0"),
  37                 },
  38         },
  39         /* Add more matching tables here..*/
  40         {}
  41 };
  42
  43 static int asus_acpi_get_sensor_info(struct acpi_device *adev,
  44                                      struct i2c_client *client,
  45                                      struct i2c_board_info *info)
  46 {
  47         struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
  48         int i;
  49         acpi_status status;
  50         union acpi_object *cpm;
  51         int ret;
  52
  53         status = acpi_evaluate_object(adev->handle, "CNF0", NULL, &buffer);
  54         if (ACPI_FAILURE(status))
  55                 return -ENODEV;
  56
  57         cpm = buffer.pointer;
  58         for (i = 0; i < cpm->package.count; ++i) {
  59                 union acpi_object *elem;
  60                 int j;
  61
  62                 elem = &cpm->package.elements[i];
  63                 for (j = 0; j < elem->package.count; ++j) {
  64                         union acpi_object *sub_elem;
  65
  66                         sub_elem = &elem->package.elements[j];
  67                         if (sub_elem->type == ACPI_TYPE_STRING)
  68                                 strscpy(info->type, sub_elem->string.pointer,
  69                                         sizeof(info->type));
  70                         else if (sub_elem->type == ACPI_TYPE_INTEGER) {
  71                                 if (sub_elem->integer.value != client->addr) {
  72                                         info->addr = sub_elem->integer.value;
  73                                         break; /* Not a MPU6500 primary */
  74                                 }
  75                         }
  76                 }
  77         }
  78         ret = cpm->package.count;
  79         kfree(buffer.pointer);
  80
  81         return ret;
  82 }
  83
  84 static int acpi_i2c_check_resource(struct acpi_resource *ares, void *data)
  85 {
  86         struct acpi_resource_i2c_serialbus *sb;
  87         u32 *addr = data;
  88
  89         if (i2c_acpi_get_i2c_resource(ares, &sb)) {
  90                 if (*addr)
  91                         *addr |= (sb->slave_address << 16);
  92                 else
  93                         *addr = sb->slave_address;
  94         }
  95
  96         /* Tell the ACPI core that we already copied this address */
  97         return 1;
  98 }
  99
 100 static int inv_mpu_process_acpi_config(struct i2c_client *client,
 101                                        unsigned short *primary_addr,
 102                                        unsigned short *secondary_addr)
 103 {
 104         struct acpi_device *adev = ACPI_COMPANION(&client->dev);
 105         const struct acpi_device_id *id;
 106         u32 i2c_addr = 0;
 107         LIST_HEAD(resources);
 108         int ret;
 109
 110         id = acpi_match_device(client->dev.driver->acpi_match_table,
 111                                &client->dev);
 112         if (!id)
 113                 return -ENODEV;
 114
 115         ret = acpi_dev_get_resources(adev, &resources,
 116                                      acpi_i2c_check_resource, &i2c_addr);
 117         if (ret < 0)
 118                 return ret;
 119
 120         acpi_dev_free_resource_list(&resources);
 121         *primary_addr = i2c_addr & 0x0000ffff;
 122         *secondary_addr = (i2c_addr & 0xffff0000) >> 16;
 123
 124         return 0;
 125 }
 126
 127 int inv_mpu_acpi_create_mux_client(struct i2c_client *client)
 128 {
 129         struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(&client->dev));
 130         struct acpi_device *adev = ACPI_COMPANION(&client->dev);
 131
 132         st->mux_client = NULL;
 133         if (adev) {
 134                 struct i2c_board_info info;
 135                 struct i2c_client *mux_client;
 136                 int ret = -1;
 137
 138                 memset(&info, 0, sizeof(info));
 139
 140                 dmi_check_system(inv_mpu_dev_list);
 141                 switch (matched_product_name) {
 142                 case INV_MPU_ASUS_T100TA:
 143                         ret = asus_acpi_get_sensor_info(adev, client,
 144                                                         &info);
 145                         break;
 146                 /* Add more matched product processing here */
 147                 default:
 148                         break;
 149                 }
 150
 151                 if (ret < 0) {
 152                         /* No matching DMI, so create device on INV6XX type */
 153                         unsigned short primary, secondary;
 154
 155                         ret = inv_mpu_process_acpi_config(client, &primary,
 156                                                           &secondary);
 157                         if (!ret && secondary) {
 158                                 char *name;
 159
 160                                 info.addr = secondary;
 161                                 strscpy(info.type, dev_name(&adev->dev),
 162                                         sizeof(info.type));
 163                                 name = strchr(info.type, ':');
 164                                 if (name)
 165                                         *name = '\0';
 166                                 strlcat(info.type, "-client",
 167                                         sizeof(info.type));
 168                         } else
 169                                 return 0; /* no secondary addr, which is OK */
 170                 }
 171                 mux_client = i2c_new_client_device(st->muxc->adapter[0], &info);
 172                 if (IS_ERR(mux_client))
 173                         return PTR_ERR(mux_client);
 174                 st->mux_client = mux_client;
 175         }
 176
 177         return 0;
 178 }
 179
 180 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client)
 181 {
 182         struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(&client->dev));
 183
 184         i2c_unregister_device(st->mux_client);
 185 }
 186 #else
 187
 188 #include "inv_mpu_iio.h"
 189
 190 int inv_mpu_acpi_create_mux_client(struct i2c_client *client)
 191 {
 192         return 0;
 193 }
 194
 195 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client)
 196 {
 197 }
 198 #endif