drivers/iio/accel/da311.c

   1 /**
   2  * IIO driver for the MiraMEMS DA311 3-axis accelerometer
   3  *
   4  * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
   5  * Copyright (c) 2011-2013 MiraMEMS Sensing Technology Co., Ltd.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms and conditions of the GNU General Public License,
   9  * version 2, as published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/i2c.h>
  14 #include <linux/iio/iio.h>
  15 #include <linux/iio/sysfs.h>
  16 #include <linux/byteorder/generic.h>
  17
  18 #define DA311_CHIP_ID                   0x13
  19
  20 /*
  21  * Note register addressed go from 0 - 0x3f and then wrap.
  22  * For some reason there are 2 banks with 0 - 0x3f addresses,
  23  * rather then a single 0-0x7f bank.
  24  */
  25
  26 /* Bank 0 regs */
  27 #define DA311_REG_BANK                  0x0000
  28 #define DA311_REG_LDO_REG               0x0006
  29 #define DA311_REG_CHIP_ID               0x000f
  30 #define DA311_REG_TEMP_CFG_REG          0x001f
  31 #define DA311_REG_CTRL_REG1             0x0020
  32 #define DA311_REG_CTRL_REG3             0x0022
  33 #define DA311_REG_CTRL_REG4             0x0023
  34 #define DA311_REG_CTRL_REG5             0x0024
  35 #define DA311_REG_CTRL_REG6             0x0025
  36 #define DA311_REG_STATUS_REG            0x0027
  37 #define DA311_REG_OUT_X_L               0x0028
  38 #define DA311_REG_OUT_X_H               0x0029
  39 #define DA311_REG_OUT_Y_L               0x002a
  40 #define DA311_REG_OUT_Y_H               0x002b
  41 #define DA311_REG_OUT_Z_L               0x002c
  42 #define DA311_REG_OUT_Z_H               0x002d
  43 #define DA311_REG_INT1_CFG              0x0030
  44 #define DA311_REG_INT1_SRC              0x0031
  45 #define DA311_REG_INT1_THS              0x0032
  46 #define DA311_REG_INT1_DURATION         0x0033
  47 #define DA311_REG_INT2_CFG              0x0034
  48 #define DA311_REG_INT2_SRC              0x0035
  49 #define DA311_REG_INT2_THS              0x0036
  50 #define DA311_REG_INT2_DURATION         0x0037
  51 #define DA311_REG_CLICK_CFG             0x0038
  52 #define DA311_REG_CLICK_SRC             0x0039
  53 #define DA311_REG_CLICK_THS             0x003a
  54 #define DA311_REG_TIME_LIMIT            0x003b
  55 #define DA311_REG_TIME_LATENCY          0x003c
  56 #define DA311_REG_TIME_WINDOW           0x003d
  57
  58 /* Bank 1 regs */
  59 #define DA311_REG_SOFT_RESET            0x0105
  60 #define DA311_REG_OTP_XOFF_L            0x0110
  61 #define DA311_REG_OTP_XOFF_H            0x0111
  62 #define DA311_REG_OTP_YOFF_L            0x0112
  63 #define DA311_REG_OTP_YOFF_H            0x0113
  64 #define DA311_REG_OTP_ZOFF_L            0x0114
  65 #define DA311_REG_OTP_ZOFF_H            0x0115
  66 #define DA311_REG_OTP_XSO               0x0116
  67 #define DA311_REG_OTP_YSO               0x0117
  68 #define DA311_REG_OTP_ZSO               0x0118
  69 #define DA311_REG_OTP_TRIM_OSC          0x011b
  70 #define DA311_REG_LPF_ABSOLUTE          0x011c
  71 #define DA311_REG_TEMP_OFF1             0x0127
  72 #define DA311_REG_TEMP_OFF2             0x0128
  73 #define DA311_REG_TEMP_OFF3             0x0129
  74 #define DA311_REG_OTP_TRIM_THERM_H      0x011a
  75
  76 /*
  77  * a value of + or -1024 corresponds to + or - 1G
  78  * scale = 9.81 / 1024 = 0.009580078
  79  */
  80
  81 static const int da311_nscale = 9580078;
  82
  83 #define DA311_CHANNEL(reg, axis) {      \
  84         .type = IIO_ACCEL,      \
  85         .address = reg, \
  86         .modified = 1,  \
  87         .channel2 = IIO_MOD_##axis,     \
  88         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
  89         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
  90 }
  91
  92 static const struct iio_chan_spec da311_channels[] = {
  93         /* | 0x80 comes from the android driver */
  94         DA311_CHANNEL(DA311_REG_OUT_X_L | 0x80, X),
  95         DA311_CHANNEL(DA311_REG_OUT_Y_L | 0x80, Y),
  96         DA311_CHANNEL(DA311_REG_OUT_Z_L | 0x80, Z),
  97 };
  98
  99 struct da311_data {
 100         struct i2c_client *client;
 101 };
 102
 103 static int da311_register_mask_write(struct i2c_client *client, u16 addr,
 104                                      u8 mask, u8 data)
 105 {
 106         int ret;
 107         u8 tmp_data = 0;
 108
 109         if (addr & 0xff00) {
 110                 /* Select bank 1 */
 111                 ret = i2c_smbus_write_byte_data(client, DA311_REG_BANK, 0x01);
 112                 if (ret < 0)
 113                         return ret;
 114         }
 115
 116         if (mask != 0xff) {
 117                 ret = i2c_smbus_read_byte_data(client, addr);
 118                 if (ret < 0)
 119                         return ret;
 120                 tmp_data = ret;
 121         }
 122
 123         tmp_data &= ~mask;
 124         tmp_data |= data & mask;
 125         ret = i2c_smbus_write_byte_data(client, addr & 0xff, tmp_data);
 126         if (ret < 0)
 127                 return ret;
 128
 129         if (addr & 0xff00) {
 130                 /* Back to bank 0 */
 131                 ret = i2c_smbus_write_byte_data(client, DA311_REG_BANK, 0x00);
 132                 if (ret < 0)
 133                         return ret;
 134         }
 135
 136         return 0;
 137 }
 138
 139 /* Init sequence taken from the android driver */
 140 static int da311_reset(struct i2c_client *client)
 141 {
 142         static const struct {
 143                 u16 addr;
 144                 u8 mask;
 145                 u8 data;
 146         } init_data[] = {
 147                 { DA311_REG_TEMP_CFG_REG,       0xff,   0x08 },
 148                 { DA311_REG_CTRL_REG5,          0xff,   0x80 },
 149                 { DA311_REG_CTRL_REG4,          0x30,   0x00 },
 150                 { DA311_REG_CTRL_REG1,          0xff,   0x6f },
 151                 { DA311_REG_TEMP_CFG_REG,       0xff,   0x88 },
 152                 { DA311_REG_LDO_REG,            0xff,   0x02 },
 153                 { DA311_REG_OTP_TRIM_OSC,       0xff,   0x27 },
 154                 { DA311_REG_LPF_ABSOLUTE,       0xff,   0x30 },
 155                 { DA311_REG_TEMP_OFF1,          0xff,   0x3f },
 156                 { DA311_REG_TEMP_OFF2,          0xff,   0xff },
 157                 { DA311_REG_TEMP_OFF3,          0xff,   0x0f },
 158         };
 159         int i, ret;
 160
 161         /* Reset */
 162         ret = da311_register_mask_write(client, DA311_REG_SOFT_RESET,
 163                                         0xff, 0xaa);
 164         if (ret < 0)
 165                 return ret;
 166
 167         for (i = 0; i < ARRAY_SIZE(init_data); i++) {
 168                 ret = da311_register_mask_write(client,
 169                                                 init_data[i].addr,
 170                                                 init_data[i].mask,
 171                                                 init_data[i].data);
 172                 if (ret < 0)
 173                         return ret;
 174         }
 175
 176         return 0;
 177 }
 178
 179 static int da311_enable(struct i2c_client *client, bool enable)
 180 {
 181         u8 data = enable ? 0x00 : 0x20;
 182
 183         return da311_register_mask_write(client, DA311_REG_TEMP_CFG_REG,
 184                                          0x20, data);
 185 }
 186
 187 static int da311_read_raw(struct iio_dev *indio_dev,
 188                                 struct iio_chan_spec const *chan,
 189                                 int *val, int *val2, long mask)
 190 {
 191         struct da311_data *data = iio_priv(indio_dev);
 192         int ret;
 193
 194         switch (mask) {
 195         case IIO_CHAN_INFO_RAW:
 196                 ret = i2c_smbus_read_word_data(data->client, chan->address);
 197                 if (ret < 0)
 198                         return ret;
 199                 /*
 200                  * Values are 12 bits, stored as 16 bits with the 4
 201                  * least significant bits always 0.
 202                  */
 203                 *val = (short)ret >> 4;
 204                 return IIO_VAL_INT;
 205         case IIO_CHAN_INFO_SCALE:
 206                 *val = 0;
 207                 *val2 = da311_nscale;
 208                 return IIO_VAL_INT_PLUS_NANO;
 209         default:
 210                 return -EINVAL;
 211         }
 212 }
 213
 214 static const struct iio_info da311_info = {
 215         .driver_module  = THIS_MODULE,
 216         .read_raw       = da311_read_raw,
 217 };
 218
 219 static int da311_probe(struct i2c_client *client,
 220                         const struct i2c_device_id *id)
 221 {
 222         int ret;
 223         struct iio_dev *indio_dev;
 224         struct da311_data *data;
 225
 226         ret = i2c_smbus_read_byte_data(client, DA311_REG_CHIP_ID);
 227         if (ret != DA311_CHIP_ID)
 228                 return (ret < 0) ? ret : -ENODEV;
 229
 230         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 231         if (!indio_dev)
 232                 return -ENOMEM;
 233
 234         data = iio_priv(indio_dev);
 235         data->client = client;
 236         i2c_set_clientdata(client, indio_dev);
 237
 238         indio_dev->dev.parent = &client->dev;
 239         indio_dev->info = &da311_info;
 240         indio_dev->name = "da311";
 241         indio_dev->modes = INDIO_DIRECT_MODE;
 242         indio_dev->channels = da311_channels;
 243         indio_dev->num_channels = ARRAY_SIZE(da311_channels);
 244
 245         ret = da311_reset(client);
 246         if (ret < 0)
 247                 return ret;
 248
 249         ret = da311_enable(client, true);
 250         if (ret < 0)
 251                 return ret;
 252
 253         ret = iio_device_register(indio_dev);
 254         if (ret < 0) {
 255                 dev_err(&client->dev, "device_register failed\n");
 256                 da311_enable(client, false);
 257         }
 258
 259         return ret;
 260 }
 261
 262 static int da311_remove(struct i2c_client *client)
 263 {
 264         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 265
 266         iio_device_unregister(indio_dev);
 267
 268         return da311_enable(client, false);
 269 }
 270
 271 #ifdef CONFIG_PM_SLEEP
 272 static int da311_suspend(struct device *dev)
 273 {
 274         return da311_enable(to_i2c_client(dev), false);
 275 }
 276
 277 static int da311_resume(struct device *dev)
 278 {
 279         return da311_enable(to_i2c_client(dev), true);
 280 }
 281 #endif
 282
 283 static SIMPLE_DEV_PM_OPS(da311_pm_ops, da311_suspend, da311_resume);
 284
 285 static const struct i2c_device_id da311_i2c_id[] = {
 286         {"da311", 0},
 287         {}
 288 };
 289 MODULE_DEVICE_TABLE(i2c, da311_i2c_id);
 290
 291 static struct i2c_driver da311_driver = {
 292         .driver = {
 293                 .name = "da311",
 294                 .pm = &da311_pm_ops,
 295         },
 296         .probe          = da311_probe,
 297         .remove         = da311_remove,
 298         .id_table       = da311_i2c_id,
 299 };
 300
 301 module_i2c_driver(da311_driver);
 302
 303 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 304 MODULE_DESCRIPTION("MiraMEMS DA311 3-Axis Accelerometer driver");
 305 MODULE_LICENSE("GPL v2");