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1// SPDX-License-Identifier: GPL-2.0+2/*3 * ti-adc161s626.c - Texas Instruments ADC161S626 1-channel differential ADC4 *5 * ADC Devices Supported:6 * adc141s626 - 14-bit ADC7 * adc161s626 - 16-bit ADC8 *9 * Copyright (C) 2016-201810 * Author: Matt Ranostay <matt.ranostay@konsulko.com>11 */12 13#include <linux/module.h>14#include <linux/mod_devicetable.h>15#include <linux/init.h>16#include <linux/err.h>17#include <linux/spi/spi.h>18#include <linux/iio/iio.h>19#include <linux/iio/trigger.h>20#include <linux/iio/buffer.h>21#include <linux/iio/trigger_consumer.h>22#include <linux/iio/triggered_buffer.h>23#include <linux/regulator/consumer.h>24 25#define TI_ADC_DRV_NAME "ti-adc161s626"26 27enum {28 TI_ADC141S626,29 TI_ADC161S626,30};31 32static const struct iio_chan_spec ti_adc141s626_channels[] = {33 {34 .type = IIO_VOLTAGE,35 .channel = 0,36 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |37 BIT(IIO_CHAN_INFO_SCALE) |38 BIT(IIO_CHAN_INFO_OFFSET),39 .scan_index = 0,40 .scan_type = {41 .sign = 's',42 .realbits = 14,43 .storagebits = 16,44 },45 },46 IIO_CHAN_SOFT_TIMESTAMP(1),47};48 49static const struct iio_chan_spec ti_adc161s626_channels[] = {50 {51 .type = IIO_VOLTAGE,52 .channel = 0,53 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |54 BIT(IIO_CHAN_INFO_SCALE) |55 BIT(IIO_CHAN_INFO_OFFSET),56 .scan_index = 0,57 .scan_type = {58 .sign = 's',59 .realbits = 16,60 .storagebits = 16,61 },62 },63 IIO_CHAN_SOFT_TIMESTAMP(1),64};65 66struct ti_adc_data {67 struct iio_dev *indio_dev;68 struct spi_device *spi;69 struct regulator *ref;70 71 u8 read_size;72 u8 shift;73 74 u8 buffer[16] __aligned(IIO_DMA_MINALIGN);75};76 77static int ti_adc_read_measurement(struct ti_adc_data *data,78 struct iio_chan_spec const *chan, int *val)79{80 int ret;81 82 switch (data->read_size) {83 case 2: {84 __be16 buf;85 86 ret = spi_read(data->spi, (void *) &buf, 2);87 if (ret)88 return ret;89 90 *val = be16_to_cpu(buf);91 break;92 }93 case 3: {94 __be32 buf;95 96 ret = spi_read(data->spi, (void *) &buf, 3);97 if (ret)98 return ret;99 100 *val = be32_to_cpu(buf) >> 8;101 break;102 }103 default:104 return -EINVAL;105 }106 107 *val = sign_extend32(*val >> data->shift, chan->scan_type.realbits - 1);108 109 return 0;110}111 112static irqreturn_t ti_adc_trigger_handler(int irq, void *private)113{114 struct iio_poll_func *pf = private;115 struct iio_dev *indio_dev = pf->indio_dev;116 struct ti_adc_data *data = iio_priv(indio_dev);117 int ret;118 119 ret = ti_adc_read_measurement(data, &indio_dev->channels[0],120 (int *) &data->buffer);121 if (!ret)122 iio_push_to_buffers_with_timestamp(indio_dev,123 data->buffer,124 iio_get_time_ns(indio_dev));125 126 iio_trigger_notify_done(indio_dev->trig);127 128 return IRQ_HANDLED;129}130 131static int ti_adc_read_raw(struct iio_dev *indio_dev,132 struct iio_chan_spec const *chan,133 int *val, int *val2, long mask)134{135 struct ti_adc_data *data = iio_priv(indio_dev);136 int ret;137 138 switch (mask) {139 case IIO_CHAN_INFO_RAW:140 iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {141 ret = ti_adc_read_measurement(data, chan, val);142 if (ret)143 return ret;144 return IIO_VAL_INT;145 }146 unreachable();147 case IIO_CHAN_INFO_SCALE:148 ret = regulator_get_voltage(data->ref);149 if (ret < 0)150 return ret;151 152 *val = ret / 1000;153 *val2 = chan->scan_type.realbits;154 155 return IIO_VAL_FRACTIONAL_LOG2;156 case IIO_CHAN_INFO_OFFSET:157 *val = 1 << (chan->scan_type.realbits - 1);158 return IIO_VAL_INT;159 }160 161 return 0;162}163 164static const struct iio_info ti_adc_info = {165 .read_raw = ti_adc_read_raw,166};167 168static void ti_adc_reg_disable(void *reg)169{170 regulator_disable(reg);171}172 173static int ti_adc_probe(struct spi_device *spi)174{175 struct iio_dev *indio_dev;176 struct ti_adc_data *data;177 int ret;178 179 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data));180 if (!indio_dev)181 return -ENOMEM;182 183 indio_dev->info = &ti_adc_info;184 indio_dev->name = TI_ADC_DRV_NAME;185 indio_dev->modes = INDIO_DIRECT_MODE;186 187 data = iio_priv(indio_dev);188 data->spi = spi;189 190 switch (spi_get_device_id(spi)->driver_data) {191 case TI_ADC141S626:192 indio_dev->channels = ti_adc141s626_channels;193 indio_dev->num_channels = ARRAY_SIZE(ti_adc141s626_channels);194 data->shift = 0;195 data->read_size = 2;196 break;197 case TI_ADC161S626:198 indio_dev->channels = ti_adc161s626_channels;199 indio_dev->num_channels = ARRAY_SIZE(ti_adc161s626_channels);200 data->shift = 6;201 data->read_size = 3;202 break;203 }204 205 data->ref = devm_regulator_get(&spi->dev, "vdda");206 if (IS_ERR(data->ref))207 return PTR_ERR(data->ref);208 209 ret = regulator_enable(data->ref);210 if (ret < 0)211 return ret;212 213 ret = devm_add_action_or_reset(&spi->dev, ti_adc_reg_disable,214 data->ref);215 if (ret)216 return ret;217 218 ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL,219 ti_adc_trigger_handler, NULL);220 if (ret)221 return ret;222 223 return devm_iio_device_register(&spi->dev, indio_dev);224}225 226static const struct of_device_id ti_adc_dt_ids[] = {227 { .compatible = "ti,adc141s626", },228 { .compatible = "ti,adc161s626", },229 { }230};231MODULE_DEVICE_TABLE(of, ti_adc_dt_ids);232 233static const struct spi_device_id ti_adc_id[] = {234 { "adc141s626", TI_ADC141S626 },235 { "adc161s626", TI_ADC161S626 },236 { }237};238MODULE_DEVICE_TABLE(spi, ti_adc_id);239 240static struct spi_driver ti_adc_driver = {241 .driver = {242 .name = TI_ADC_DRV_NAME,243 .of_match_table = ti_adc_dt_ids,244 },245 .probe = ti_adc_probe,246 .id_table = ti_adc_id,247};248module_spi_driver(ti_adc_driver);249 250MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");251MODULE_DESCRIPTION("Texas Instruments ADC1x1S 1-channel differential ADC");252MODULE_LICENSE("GPL");253