// SPDX-License-Identifier: GPL-2.0-only /* * TI ADC081C/ADC101C/ADC121C 8/10/12-bit ADC driver * * Copyright (C) 2012 Avionic Design GmbH * Copyright (C) 2016 Intel * * Datasheets: * http://www.ti.com/lit/ds/symlink/adc081c021.pdf * http://www.ti.com/lit/ds/symlink/adc101c021.pdf * http://www.ti.com/lit/ds/symlink/adc121c021.pdf * * The devices have a very similar interface and differ mostly in the number of * bits handled. For the 8-bit and 10-bit models the least-significant 4 or 2 * bits of value registers are reserved. */ #include #include #include #include #include #include #include #include #include #include struct adc081c { struct i2c_client *i2c; struct regulator *ref; /* 8, 10 or 12 */ int bits; }; #define REG_CONV_RES 0x00 static int adc081c_read_raw(struct iio_dev *iio, struct iio_chan_spec const *channel, int *value, int *shift, long mask) { struct adc081c *adc = iio_priv(iio); int err; switch (mask) { case IIO_CHAN_INFO_RAW: err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES); if (err < 0) return err; *value = (err & 0xFFF) >> (12 - adc->bits); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: err = regulator_get_voltage(adc->ref); if (err < 0) return err; *value = err / 1000; *shift = adc->bits; return IIO_VAL_FRACTIONAL_LOG2; default: break; } return -EINVAL; } #define ADCxx1C_CHAN(_bits) { \ .type = IIO_VOLTAGE, \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .scan_type = { \ .sign = 'u', \ .realbits = (_bits), \ .storagebits = 16, \ .shift = 12 - (_bits), \ .endianness = IIO_CPU, \ }, \ } #define DEFINE_ADCxx1C_CHANNELS(_name, _bits) \ static const struct iio_chan_spec _name ## _channels[] = { \ ADCxx1C_CHAN((_bits)), \ IIO_CHAN_SOFT_TIMESTAMP(1), \ }; \ #define ADC081C_NUM_CHANNELS 2 struct adcxx1c_model { const struct iio_chan_spec* channels; int bits; }; #define ADCxx1C_MODEL(_name, _bits) \ { \ .channels = _name ## _channels, \ .bits = (_bits), \ } DEFINE_ADCxx1C_CHANNELS(adc081c, 8); DEFINE_ADCxx1C_CHANNELS(adc101c, 10); DEFINE_ADCxx1C_CHANNELS(adc121c, 12); /* Model ids are indexes in _models array */ enum adcxx1c_model_id { ADC081C = 0, ADC101C = 1, ADC121C = 2, }; static struct adcxx1c_model adcxx1c_models[] = { ADCxx1C_MODEL(adc081c, 8), ADCxx1C_MODEL(adc101c, 10), ADCxx1C_MODEL(adc121c, 12), }; static const struct iio_info adc081c_info = { .read_raw = adc081c_read_raw, }; static irqreturn_t adc081c_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct adc081c *data = iio_priv(indio_dev); u16 buf[8]; /* 2 bytes data + 6 bytes padding + 8 bytes timestamp */ int ret; ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES); if (ret < 0) goto out; buf[0] = ret; iio_push_to_buffers_with_timestamp(indio_dev, buf, iio_get_time_ns(indio_dev)); out: iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int adc081c_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct iio_dev *iio; struct adc081c *adc; struct adcxx1c_model *model; int err; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) return -EOPNOTSUPP; if (ACPI_COMPANION(&client->dev)) { const struct acpi_device_id *ad_id; ad_id = acpi_match_device(client->dev.driver->acpi_match_table, &client->dev); if (!ad_id) return -ENODEV; model = &adcxx1c_models[ad_id->driver_data]; } else { model = &adcxx1c_models[id->driver_data]; } iio = devm_iio_device_alloc(&client->dev, sizeof(*adc)); if (!iio) return -ENOMEM; adc = iio_priv(iio); adc->i2c = client; adc->bits = model->bits; adc->ref = devm_regulator_get(&client->dev, "vref"); if (IS_ERR(adc->ref)) return PTR_ERR(adc->ref); err = regulator_enable(adc->ref); if (err < 0) return err; iio->dev.parent = &client->dev; iio->dev.of_node = client->dev.of_node; iio->name = dev_name(&client->dev); iio->modes = INDIO_DIRECT_MODE; iio->info = &adc081c_info; iio->channels = model->channels; iio->num_channels = ADC081C_NUM_CHANNELS; err = iio_triggered_buffer_setup(iio, NULL, adc081c_trigger_handler, NULL); if (err < 0) { dev_err(&client->dev, "iio triggered buffer setup failed\n"); goto err_regulator_disable; } err = iio_device_register(iio); if (err < 0) goto err_buffer_cleanup; i2c_set_clientdata(client, iio); return 0; err_buffer_cleanup: iio_triggered_buffer_cleanup(iio); err_regulator_disable: regulator_disable(adc->ref); return err; } static int adc081c_remove(struct i2c_client *client) { struct iio_dev *iio = i2c_get_clientdata(client); struct adc081c *adc = iio_priv(iio); iio_device_unregister(iio); iio_triggered_buffer_cleanup(iio); regulator_disable(adc->ref); return 0; } static const struct i2c_device_id adc081c_id[] = { { "adc081c", ADC081C }, { "adc101c", ADC101C }, { "adc121c", ADC121C }, { } }; MODULE_DEVICE_TABLE(i2c, adc081c_id); #ifdef CONFIG_OF static const struct of_device_id adc081c_of_match[] = { { .compatible = "ti,adc081c" }, { .compatible = "ti,adc101c" }, { .compatible = "ti,adc121c" }, { } }; MODULE_DEVICE_TABLE(of, adc081c_of_match); #endif #ifdef CONFIG_ACPI static const struct acpi_device_id adc081c_acpi_match[] = { { "ADC081C", ADC081C }, { "ADC101C", ADC101C }, { "ADC121C", ADC121C }, { } }; MODULE_DEVICE_TABLE(acpi, adc081c_acpi_match); #endif static struct i2c_driver adc081c_driver = { .driver = { .name = "adc081c", .of_match_table = of_match_ptr(adc081c_of_match), .acpi_match_table = ACPI_PTR(adc081c_acpi_match), }, .probe = adc081c_probe, .remove = adc081c_remove, .id_table = adc081c_id, }; module_i2c_driver(adc081c_driver); MODULE_AUTHOR("Thierry Reding "); MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver"); MODULE_LICENSE("GPL v2");