1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * tsys02d.c - Support for Measurement-Specialties tsys02d temperature sensor 4 * 5 * Copyright (c) 2015 Measurement-Specialties 6 * 7 * (7-bit I2C slave address 0x40) 8 * 9 * Datasheet: 10 * http://www.meas-spec.com/downloads/Digital_Sensor_TSYS02D.pdf 11 */ 12 13 #include <linux/init.h> 14 #include <linux/device.h> 15 #include <linux/kernel.h> 16 #include <linux/stat.h> 17 #include <linux/module.h> 18 #include <linux/iio/iio.h> 19 #include <linux/iio/sysfs.h> 20 21 #include "../common/ms_sensors/ms_sensors_i2c.h" 22 23 #define TSYS02D_RESET 0xFE 24 25 static const int tsys02d_samp_freq[4] = { 20, 40, 70, 140 }; 26 /* String copy of the above const for readability purpose */ 27 static const char tsys02d_show_samp_freq[] = "20 40 70 140"; 28 29 static int tsys02d_read_raw(struct iio_dev *indio_dev, 30 struct iio_chan_spec const *channel, int *val, 31 int *val2, long mask) 32 { 33 int ret; 34 s32 temperature; 35 struct ms_ht_dev *dev_data = iio_priv(indio_dev); 36 37 switch (mask) { 38 case IIO_CHAN_INFO_PROCESSED: 39 switch (channel->type) { 40 case IIO_TEMP: /* in milli °C */ 41 ret = ms_sensors_ht_read_temperature(dev_data, 42 &temperature); 43 if (ret) 44 return ret; 45 *val = temperature; 46 47 return IIO_VAL_INT; 48 default: 49 return -EINVAL; 50 } 51 case IIO_CHAN_INFO_SAMP_FREQ: 52 *val = tsys02d_samp_freq[dev_data->res_index]; 53 54 return IIO_VAL_INT; 55 default: 56 return -EINVAL; 57 } 58 } 59 60 static int tsys02d_write_raw(struct iio_dev *indio_dev, 61 struct iio_chan_spec const *chan, 62 int val, int val2, long mask) 63 { 64 struct ms_ht_dev *dev_data = iio_priv(indio_dev); 65 int i, ret; 66 67 switch (mask) { 68 case IIO_CHAN_INFO_SAMP_FREQ: 69 i = ARRAY_SIZE(tsys02d_samp_freq); 70 while (i-- > 0) 71 if (val == tsys02d_samp_freq[i]) 72 break; 73 if (i < 0) 74 return -EINVAL; 75 mutex_lock(&dev_data->lock); 76 dev_data->res_index = i; 77 ret = ms_sensors_write_resolution(dev_data, i); 78 mutex_unlock(&dev_data->lock); 79 80 return ret; 81 default: 82 return -EINVAL; 83 } 84 } 85 86 static const struct iio_chan_spec tsys02d_channels[] = { 87 { 88 .type = IIO_TEMP, 89 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED), 90 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), 91 } 92 }; 93 94 static ssize_t tsys02_read_battery_low(struct device *dev, 95 struct device_attribute *attr, 96 char *buf) 97 { 98 struct iio_dev *indio_dev = dev_to_iio_dev(dev); 99 struct ms_ht_dev *dev_data = iio_priv(indio_dev); 100 101 return ms_sensors_show_battery_low(dev_data, buf); 102 } 103 104 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(tsys02d_show_samp_freq); 105 static IIO_DEVICE_ATTR(battery_low, S_IRUGO, 106 tsys02_read_battery_low, NULL, 0); 107 108 static struct attribute *tsys02d_attributes[] = { 109 &iio_const_attr_sampling_frequency_available.dev_attr.attr, 110 &iio_dev_attr_battery_low.dev_attr.attr, 111 NULL, 112 }; 113 114 static const struct attribute_group tsys02d_attribute_group = { 115 .attrs = tsys02d_attributes, 116 }; 117 118 static const struct iio_info tsys02d_info = { 119 .read_raw = tsys02d_read_raw, 120 .write_raw = tsys02d_write_raw, 121 .attrs = &tsys02d_attribute_group, 122 }; 123 124 static int tsys02d_probe(struct i2c_client *client, 125 const struct i2c_device_id *id) 126 { 127 struct ms_ht_dev *dev_data; 128 struct iio_dev *indio_dev; 129 int ret; 130 u64 serial_number; 131 132 if (!i2c_check_functionality(client->adapter, 133 I2C_FUNC_SMBUS_WRITE_BYTE_DATA | 134 I2C_FUNC_SMBUS_WRITE_BYTE | 135 I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { 136 dev_err(&client->dev, 137 "Adapter does not support some i2c transaction\n"); 138 return -EOPNOTSUPP; 139 } 140 141 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data)); 142 if (!indio_dev) 143 return -ENOMEM; 144 145 dev_data = iio_priv(indio_dev); 146 dev_data->client = client; 147 dev_data->res_index = 0; 148 mutex_init(&dev_data->lock); 149 150 indio_dev->info = &tsys02d_info; 151 indio_dev->name = id->name; 152 indio_dev->modes = INDIO_DIRECT_MODE; 153 indio_dev->channels = tsys02d_channels; 154 indio_dev->num_channels = ARRAY_SIZE(tsys02d_channels); 155 156 i2c_set_clientdata(client, indio_dev); 157 158 ret = ms_sensors_reset(client, TSYS02D_RESET, 15000); 159 if (ret) 160 return ret; 161 162 ret = ms_sensors_read_serial(client, &serial_number); 163 if (ret) 164 return ret; 165 dev_info(&client->dev, "Serial number : %llx", serial_number); 166 167 return devm_iio_device_register(&client->dev, indio_dev); 168 } 169 170 static const struct i2c_device_id tsys02d_id[] = { 171 {"tsys02d", 0}, 172 {} 173 }; 174 MODULE_DEVICE_TABLE(i2c, tsys02d_id); 175 176 static struct i2c_driver tsys02d_driver = { 177 .probe = tsys02d_probe, 178 .id_table = tsys02d_id, 179 .driver = { 180 .name = "tsys02d", 181 }, 182 }; 183 184 module_i2c_driver(tsys02d_driver); 185 186 MODULE_DESCRIPTION("Measurement-Specialties tsys02d temperature driver"); 187 MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>"); 188 MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>"); 189 MODULE_LICENSE("GPL v2"); 190