1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * mCube MC3230 3-Axis Accelerometer 4 * 5 * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com> 6 * 7 * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c. 8 */ 9 10 #include <linux/i2c.h> 11 #include <linux/module.h> 12 #include <linux/iio/iio.h> 13 #include <linux/iio/sysfs.h> 14 15 #define MC3230_REG_XOUT 0x00 16 #define MC3230_REG_YOUT 0x01 17 #define MC3230_REG_ZOUT 0x02 18 19 #define MC3230_REG_MODE 0x07 20 #define MC3230_MODE_OPCON_MASK 0x03 21 #define MC3230_MODE_OPCON_WAKE 0x01 22 #define MC3230_MODE_OPCON_STANDBY 0x03 23 24 #define MC3230_REG_CHIP_ID 0x18 25 #define MC3230_CHIP_ID 0x01 26 27 #define MC3230_REG_PRODUCT_CODE 0x3b 28 #define MC3230_PRODUCT_CODE 0x19 29 30 /* 31 * The accelerometer has one measurement range: 32 * 33 * -1.5g - +1.5g (8-bit, signed) 34 * 35 * scale = (1.5 + 1.5) * 9.81 / (2^8 - 1) = 0.115411765 36 */ 37 38 static const int mc3230_nscale = 115411765; 39 40 #define MC3230_CHANNEL(reg, axis) { \ 41 .type = IIO_ACCEL, \ 42 .address = reg, \ 43 .modified = 1, \ 44 .channel2 = IIO_MOD_##axis, \ 45 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 46 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 47 } 48 49 static const struct iio_chan_spec mc3230_channels[] = { 50 MC3230_CHANNEL(MC3230_REG_XOUT, X), 51 MC3230_CHANNEL(MC3230_REG_YOUT, Y), 52 MC3230_CHANNEL(MC3230_REG_ZOUT, Z), 53 }; 54 55 struct mc3230_data { 56 struct i2c_client *client; 57 }; 58 59 static int mc3230_set_opcon(struct mc3230_data *data, int opcon) 60 { 61 int ret; 62 struct i2c_client *client = data->client; 63 64 ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE); 65 if (ret < 0) { 66 dev_err(&client->dev, "failed to read mode reg: %d\n", ret); 67 return ret; 68 } 69 70 ret &= ~MC3230_MODE_OPCON_MASK; 71 ret |= opcon; 72 73 ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret); 74 if (ret < 0) { 75 dev_err(&client->dev, "failed to write mode reg: %d\n", ret); 76 return ret; 77 } 78 79 return 0; 80 } 81 82 static int mc3230_read_raw(struct iio_dev *indio_dev, 83 struct iio_chan_spec const *chan, 84 int *val, int *val2, long mask) 85 { 86 struct mc3230_data *data = iio_priv(indio_dev); 87 int ret; 88 89 switch (mask) { 90 case IIO_CHAN_INFO_RAW: 91 ret = i2c_smbus_read_byte_data(data->client, chan->address); 92 if (ret < 0) 93 return ret; 94 *val = sign_extend32(ret, 7); 95 return IIO_VAL_INT; 96 case IIO_CHAN_INFO_SCALE: 97 *val = 0; 98 *val2 = mc3230_nscale; 99 return IIO_VAL_INT_PLUS_NANO; 100 default: 101 return -EINVAL; 102 } 103 } 104 105 static const struct iio_info mc3230_info = { 106 .read_raw = mc3230_read_raw, 107 }; 108 109 static int mc3230_probe(struct i2c_client *client) 110 { 111 int ret; 112 struct iio_dev *indio_dev; 113 struct mc3230_data *data; 114 115 /* First check chip-id and product-id */ 116 ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID); 117 if (ret != MC3230_CHIP_ID) 118 return (ret < 0) ? ret : -ENODEV; 119 120 ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE); 121 if (ret != MC3230_PRODUCT_CODE) 122 return (ret < 0) ? ret : -ENODEV; 123 124 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 125 if (!indio_dev) { 126 dev_err(&client->dev, "iio allocation failed!\n"); 127 return -ENOMEM; 128 } 129 130 data = iio_priv(indio_dev); 131 data->client = client; 132 i2c_set_clientdata(client, indio_dev); 133 134 indio_dev->info = &mc3230_info; 135 indio_dev->name = "mc3230"; 136 indio_dev->modes = INDIO_DIRECT_MODE; 137 indio_dev->channels = mc3230_channels; 138 indio_dev->num_channels = ARRAY_SIZE(mc3230_channels); 139 140 ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE); 141 if (ret < 0) 142 return ret; 143 144 ret = iio_device_register(indio_dev); 145 if (ret < 0) { 146 dev_err(&client->dev, "device_register failed\n"); 147 mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY); 148 } 149 150 return ret; 151 } 152 153 static void mc3230_remove(struct i2c_client *client) 154 { 155 struct iio_dev *indio_dev = i2c_get_clientdata(client); 156 157 iio_device_unregister(indio_dev); 158 159 mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY); 160 } 161 162 static int mc3230_suspend(struct device *dev) 163 { 164 struct mc3230_data *data; 165 166 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); 167 168 return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY); 169 } 170 171 static int mc3230_resume(struct device *dev) 172 { 173 struct mc3230_data *data; 174 175 data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); 176 177 return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE); 178 } 179 180 static DEFINE_SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume); 181 182 static const struct i2c_device_id mc3230_i2c_id[] = { 183 {"mc3230", 0}, 184 {} 185 }; 186 MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id); 187 188 static struct i2c_driver mc3230_driver = { 189 .driver = { 190 .name = "mc3230", 191 .pm = pm_sleep_ptr(&mc3230_pm_ops), 192 }, 193 .probe_new = mc3230_probe, 194 .remove = mc3230_remove, 195 .id_table = mc3230_i2c_id, 196 }; 197 198 module_i2c_driver(mc3230_driver); 199 200 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 201 MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver"); 202 MODULE_LICENSE("GPL v2"); 203