1 // SPDX-License-Identifier: GPL-2.0-only 2 /** 3 * IIO driver for the MiraMEMS 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 enum da280_chipset { da226, da280 }; 27 28 /* 29 * a value of + or -4096 corresponds to + or - 1G 30 * scale = 9.81 / 4096 = 0.002395019 31 */ 32 33 static const int da280_nscale = 2395019; 34 35 #define DA280_CHANNEL(reg, axis) { \ 36 .type = IIO_ACCEL, \ 37 .address = reg, \ 38 .modified = 1, \ 39 .channel2 = IIO_MOD_##axis, \ 40 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 41 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 42 } 43 44 static const struct iio_chan_spec da280_channels[] = { 45 DA280_CHANNEL(DA280_REG_ACC_X_LSB, X), 46 DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y), 47 DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z), 48 }; 49 50 struct da280_data { 51 struct i2c_client *client; 52 }; 53 54 static int da280_enable(struct i2c_client *client, bool enable) 55 { 56 u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE; 57 58 return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data); 59 } 60 61 static int da280_read_raw(struct iio_dev *indio_dev, 62 struct iio_chan_spec const *chan, 63 int *val, int *val2, long mask) 64 { 65 struct da280_data *data = iio_priv(indio_dev); 66 int ret; 67 68 switch (mask) { 69 case IIO_CHAN_INFO_RAW: 70 ret = i2c_smbus_read_word_data(data->client, chan->address); 71 if (ret < 0) 72 return ret; 73 /* 74 * Values are 14 bits, stored as 16 bits with the 2 75 * least significant bits always 0. 76 */ 77 *val = (short)ret >> 2; 78 return IIO_VAL_INT; 79 case IIO_CHAN_INFO_SCALE: 80 *val = 0; 81 *val2 = da280_nscale; 82 return IIO_VAL_INT_PLUS_NANO; 83 default: 84 return -EINVAL; 85 } 86 } 87 88 static const struct iio_info da280_info = { 89 .read_raw = da280_read_raw, 90 }; 91 92 static enum da280_chipset da280_match_acpi_device(struct device *dev) 93 { 94 const struct acpi_device_id *id; 95 96 id = acpi_match_device(dev->driver->acpi_match_table, dev); 97 if (!id) 98 return -EINVAL; 99 100 return (enum da280_chipset) id->driver_data; 101 } 102 103 static int da280_probe(struct i2c_client *client, 104 const struct i2c_device_id *id) 105 { 106 int ret; 107 struct iio_dev *indio_dev; 108 struct da280_data *data; 109 enum da280_chipset chip; 110 111 ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID); 112 if (ret != DA280_CHIP_ID) 113 return (ret < 0) ? ret : -ENODEV; 114 115 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 116 if (!indio_dev) 117 return -ENOMEM; 118 119 data = iio_priv(indio_dev); 120 data->client = client; 121 i2c_set_clientdata(client, indio_dev); 122 123 indio_dev->dev.parent = &client->dev; 124 indio_dev->info = &da280_info; 125 indio_dev->modes = INDIO_DIRECT_MODE; 126 indio_dev->channels = da280_channels; 127 128 if (ACPI_HANDLE(&client->dev)) { 129 chip = da280_match_acpi_device(&client->dev); 130 } else { 131 chip = id->driver_data; 132 } 133 134 if (chip == da226) { 135 indio_dev->name = "da226"; 136 indio_dev->num_channels = 2; 137 } else { 138 indio_dev->name = "da280"; 139 indio_dev->num_channels = 3; 140 } 141 142 ret = da280_enable(client, true); 143 if (ret < 0) 144 return ret; 145 146 ret = iio_device_register(indio_dev); 147 if (ret < 0) { 148 dev_err(&client->dev, "device_register failed\n"); 149 da280_enable(client, false); 150 } 151 152 return ret; 153 } 154 155 static int da280_remove(struct i2c_client *client) 156 { 157 struct iio_dev *indio_dev = i2c_get_clientdata(client); 158 159 iio_device_unregister(indio_dev); 160 161 return da280_enable(client, false); 162 } 163 164 #ifdef CONFIG_PM_SLEEP 165 static int da280_suspend(struct device *dev) 166 { 167 return da280_enable(to_i2c_client(dev), false); 168 } 169 170 static int da280_resume(struct device *dev) 171 { 172 return da280_enable(to_i2c_client(dev), true); 173 } 174 #endif 175 176 static SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume); 177 178 static const struct acpi_device_id da280_acpi_match[] = { 179 {"MIRAACC", da280}, 180 {}, 181 }; 182 MODULE_DEVICE_TABLE(acpi, da280_acpi_match); 183 184 static const struct i2c_device_id da280_i2c_id[] = { 185 { "da226", da226 }, 186 { "da280", da280 }, 187 {} 188 }; 189 MODULE_DEVICE_TABLE(i2c, da280_i2c_id); 190 191 static struct i2c_driver da280_driver = { 192 .driver = { 193 .name = "da280", 194 .acpi_match_table = ACPI_PTR(da280_acpi_match), 195 .pm = &da280_pm_ops, 196 }, 197 .probe = da280_probe, 198 .remove = da280_remove, 199 .id_table = da280_i2c_id, 200 }; 201 202 module_i2c_driver(da280_driver); 203 204 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 205 MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver"); 206 MODULE_LICENSE("GPL v2"); 207