drivers/iio/accel/da280.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * IIO driver for the MiraMEMS DA217 and DA280 3-axis accelerometer and
   4  * IIO driver for the MiraMEMS DA226 2-axis accelerometer
   5  *
   6  * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/i2c.h>
  11 #include <linux/acpi.h>
  12 #include <linux/iio/iio.h>
  13 #include <linux/iio/sysfs.h>
  14 #include <linux/byteorder/generic.h>
  15
  16 #define DA280_REG_CHIP_ID               0x01
  17 #define DA280_REG_ACC_X_LSB             0x02
  18 #define DA280_REG_ACC_Y_LSB             0x04
  19 #define DA280_REG_ACC_Z_LSB             0x06
  20 #define DA280_REG_MODE_BW               0x11
  21
  22 #define DA280_CHIP_ID                   0x13
  23 #define DA280_MODE_ENABLE               0x1e
  24 #define DA280_MODE_DISABLE              0x9e
  25
  26 /*
  27  * a value of + or -4096 corresponds to + or - 1G
  28  * scale = 9.81 / 4096 = 0.002395019
  29  */
  30
  31 static const int da280_nscale = 2395019;
  32
  33 #define DA280_CHANNEL(reg, axis) {      \
  34         .type = IIO_ACCEL,      \
  35         .address = reg, \
  36         .modified = 1,  \
  37         .channel2 = IIO_MOD_##axis,     \
  38         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
  39         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
  40 }
  41
  42 static const struct iio_chan_spec da280_channels[] = {
  43         DA280_CHANNEL(DA280_REG_ACC_X_LSB, X),
  44         DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y),
  45         DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z),
  46 };
  47
  48 struct da280_match_data {
  49         const char *name;
  50         int num_channels;
  51 };
  52
  53 struct da280_data {
  54         struct i2c_client *client;
  55 };
  56
  57 static int da280_enable(struct i2c_client *client, bool enable)
  58 {
  59         u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE;
  60
  61         return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data);
  62 }
  63
  64 static int da280_read_raw(struct iio_dev *indio_dev,
  65                                 struct iio_chan_spec const *chan,
  66                                 int *val, int *val2, long mask)
  67 {
  68         struct da280_data *data = iio_priv(indio_dev);
  69         int ret;
  70
  71         switch (mask) {
  72         case IIO_CHAN_INFO_RAW:
  73                 ret = i2c_smbus_read_word_data(data->client, chan->address);
  74                 if (ret < 0)
  75                         return ret;
  76                 /*
  77                  * Values are 14 bits, stored as 16 bits with the 2
  78                  * least significant bits always 0.
  79                  */
  80                 *val = (short)ret >> 2;
  81                 return IIO_VAL_INT;
  82         case IIO_CHAN_INFO_SCALE:
  83                 *val = 0;
  84                 *val2 = da280_nscale;
  85                 return IIO_VAL_INT_PLUS_NANO;
  86         default:
  87                 return -EINVAL;
  88         }
  89 }
  90
  91 static const struct iio_info da280_info = {
  92         .read_raw       = da280_read_raw,
  93 };
  94
  95 static void da280_disable(void *client)
  96 {
  97         da280_enable(client, false);
  98 }
  99
 100 static int da280_probe(struct i2c_client *client)
 101 {
 102         const struct da280_match_data *match_data;
 103         struct iio_dev *indio_dev;
 104         struct da280_data *data;
 105         int ret;
 106
 107         ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID);
 108         if (ret != DA280_CHIP_ID)
 109                 return (ret < 0) ? ret : -ENODEV;
 110
 111         match_data = i2c_get_match_data(client);
 112         if (!match_data) {
 113                 dev_err(&client->dev, "Error match-data not set\n");
 114                 return -EINVAL;
 115         }
 116
 117         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 118         if (!indio_dev)
 119                 return -ENOMEM;
 120
 121         data = iio_priv(indio_dev);
 122         data->client = client;
 123
 124         indio_dev->info = &da280_info;
 125         indio_dev->modes = INDIO_DIRECT_MODE;
 126         indio_dev->channels = da280_channels;
 127         indio_dev->num_channels = match_data->num_channels;
 128         indio_dev->name = match_data->name;
 129
 130         ret = da280_enable(client, true);
 131         if (ret < 0)
 132                 return ret;
 133
 134         ret = devm_add_action_or_reset(&client->dev, da280_disable, client);
 135         if (ret)
 136                 return ret;
 137
 138         return devm_iio_device_register(&client->dev, indio_dev);
 139 }
 140
 141 static int da280_suspend(struct device *dev)
 142 {
 143         return da280_enable(to_i2c_client(dev), false);
 144 }
 145
 146 static int da280_resume(struct device *dev)
 147 {
 148         return da280_enable(to_i2c_client(dev), true);
 149 }
 150
 151 static DEFINE_SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
 152
 153 static const struct da280_match_data da217_match_data = { "da217", 3 };
 154 static const struct da280_match_data da226_match_data = { "da226", 2 };
 155 static const struct da280_match_data da280_match_data = { "da280", 3 };
 156
 157 static const struct acpi_device_id da280_acpi_match[] = {
 158         { "NSA2513", (kernel_ulong_t)&da217_match_data },
 159         { "MIRAACC", (kernel_ulong_t)&da280_match_data },
 160         {}
 161 };
 162 MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
 163
 164 static const struct i2c_device_id da280_i2c_id[] = {
 165         { "da217", (kernel_ulong_t)&da217_match_data },
 166         { "da226", (kernel_ulong_t)&da226_match_data },
 167         { "da280", (kernel_ulong_t)&da280_match_data },
 168         {}
 169 };
 170 MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
 171
 172 static struct i2c_driver da280_driver = {
 173         .driver = {
 174                 .name = "da280",
 175                 .acpi_match_table = da280_acpi_match,
 176                 .pm = pm_sleep_ptr(&da280_pm_ops),
 177         },
 178         .probe          = da280_probe,
 179         .id_table       = da280_i2c_id,
 180 };
 181
 182 module_i2c_driver(da280_driver);
 183
 184 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 185 MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
 186 MODULE_LICENSE("GPL v2");