| // 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: |
| * https://www.ti.com/lit/ds/symlink/adc081c021.pdf |
| * https://www.ti.com/lit/ds/symlink/adc101c021.pdf |
| * https://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 <linux/err.h> |
| #include <linux/i2c.h> |
| #include <linux/module.h> |
| #include <linux/mod_devicetable.h> |
| #include <linux/property.h> |
| |
| #include <linux/iio/iio.h> |
| #include <linux/iio/buffer.h> |
| #include <linux/iio/trigger_consumer.h> |
| #include <linux/iio/triggered_buffer.h> |
| #include <linux/regulator/consumer.h> |
| |
| struct adc081c { |
| struct i2c_client *i2c; |
| struct regulator *ref; |
| |
| /* 8, 10 or 12 */ |
| int bits; |
| |
| /* Ensure natural alignment of buffer elements */ |
| struct { |
| u16 channel; |
| s64 ts __aligned(8); |
| } scan; |
| }; |
| |
| #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); |
| int ret; |
| |
| ret = i2c_smbus_read_word_swapped(data->i2c, REG_CONV_RES); |
| if (ret < 0) |
| goto out; |
| data->scan.channel = ret; |
| iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, |
| iio_get_time_ns(indio_dev)); |
| out: |
| iio_trigger_notify_done(indio_dev->trig); |
| return IRQ_HANDLED; |
| } |
| |
| static void adc081c_reg_disable(void *reg) |
| { |
| regulator_disable(reg); |
| } |
| |
| static int adc081c_probe(struct i2c_client *client) |
| { |
| const struct i2c_device_id *id = i2c_client_get_device_id(client); |
| struct iio_dev *iio; |
| struct adc081c *adc; |
| const struct adcxx1c_model *model; |
| int err; |
| |
| if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) |
| return -EOPNOTSUPP; |
| |
| if (dev_fwnode(&client->dev)) |
| model = device_get_match_data(&client->dev); |
| 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; |
| |
| err = devm_add_action_or_reset(&client->dev, adc081c_reg_disable, |
| adc->ref); |
| if (err) |
| return err; |
| |
| 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 = devm_iio_triggered_buffer_setup(&client->dev, iio, NULL, |
| adc081c_trigger_handler, NULL); |
| if (err < 0) { |
| dev_err(&client->dev, "iio triggered buffer setup failed\n"); |
| return err; |
| } |
| |
| return devm_iio_device_register(&client->dev, iio); |
| } |
| |
| static const struct i2c_device_id adc081c_id[] = { |
| { "adc081c", ADC081C }, |
| { "adc101c", ADC101C }, |
| { "adc121c", ADC121C }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, adc081c_id); |
| |
| static const struct acpi_device_id adc081c_acpi_match[] = { |
| /* Used on some AAEON boards */ |
| { "ADC081C", (kernel_ulong_t)&adcxx1c_models[ADC081C] }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(acpi, adc081c_acpi_match); |
| |
| static const struct of_device_id adc081c_of_match[] = { |
| { .compatible = "ti,adc081c", .data = &adcxx1c_models[ADC081C] }, |
| { .compatible = "ti,adc101c", .data = &adcxx1c_models[ADC101C] }, |
| { .compatible = "ti,adc121c", .data = &adcxx1c_models[ADC121C] }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, adc081c_of_match); |
| |
| static struct i2c_driver adc081c_driver = { |
| .driver = { |
| .name = "adc081c", |
| .of_match_table = adc081c_of_match, |
| .acpi_match_table = adc081c_acpi_match, |
| }, |
| .probe_new = adc081c_probe, |
| .id_table = adc081c_id, |
| }; |
| module_i2c_driver(adc081c_driver); |
| |
| MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>"); |
| MODULE_DESCRIPTION("Texas Instruments ADC081C/ADC101C/ADC121C driver"); |
| MODULE_LICENSE("GPL v2"); |