iio/dac/ad5592r.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * AD5592R Digital <-> Analog converters driver
0004  *
0005  * Copyright 2015-2016 Analog Devices Inc.
0006  * Author: Paul Cercueil <paul.cercueil@analog.com>
0007  */
0008
0009 #include "ad5592r-base.h"
0010
0011 #include <linux/bitops.h>
0012 #include <linux/module.h>
0013 #include <linux/mod_devicetable.h>
0014 #include <linux/spi/spi.h>
0015
0016 #define AD5592R_GPIO_READBACK_EN    BIT(10)
0017 #define AD5592R_LDAC_READBACK_EN    BIT(6)
0018
0019 static int ad5592r_spi_wnop_r16(struct ad5592r_state *st, __be16 *buf)
0020 {
0021     struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
0022     struct spi_transfer t = {
0023             .tx_buf = &st->spi_msg_nop,
0024             .rx_buf = buf,
0025             .len = 2
0026         };
0027
0028     st->spi_msg_nop = 0; /* NOP */
0029
0030     return spi_sync_transfer(spi, &t, 1);
0031 }
0032
0033 static int ad5592r_write_dac(struct ad5592r_state *st, unsigned chan, u16 value)
0034 {
0035     struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
0036
0037     st->spi_msg = cpu_to_be16(BIT(15) | (chan << 12) | value);
0038
0039     return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
0040 }
0041
0042 static int ad5592r_read_adc(struct ad5592r_state *st, unsigned chan, u16 *value)
0043 {
0044     struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
0045     int ret;
0046
0047     st->spi_msg = cpu_to_be16((AD5592R_REG_ADC_SEQ << 11) | BIT(chan));
0048
0049     ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
0050     if (ret)
0051         return ret;
0052
0053     /*
0054      * Invalid data:
0055      * See Figure 40. Single-Channel ADC Conversion Sequence
0056      */
0057     ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
0058     if (ret)
0059         return ret;
0060
0061     ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
0062     if (ret)
0063         return ret;
0064
0065     *value = be16_to_cpu(st->spi_msg);
0066
0067     return 0;
0068 }
0069
0070 static int ad5592r_reg_write(struct ad5592r_state *st, u8 reg, u16 value)
0071 {
0072     struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
0073
0074     st->spi_msg = cpu_to_be16((reg << 11) | value);
0075
0076     return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
0077 }
0078
0079 static int ad5592r_reg_read(struct ad5592r_state *st, u8 reg, u16 *value)
0080 {
0081     struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
0082     int ret;
0083
0084     st->spi_msg = cpu_to_be16((AD5592R_REG_LDAC << 11) |
0085                    AD5592R_LDAC_READBACK_EN | (reg << 2));
0086
0087     ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
0088     if (ret)
0089         return ret;
0090
0091     ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
0092     if (ret)
0093         return ret;
0094
0095     *value = be16_to_cpu(st->spi_msg);
0096
0097     return 0;
0098 }
0099
0100 static int ad5592r_gpio_read(struct ad5592r_state *st, u8 *value)
0101 {
0102     int ret;
0103
0104     ret = ad5592r_reg_write(st, AD5592R_REG_GPIO_IN_EN,
0105                 AD5592R_GPIO_READBACK_EN | st->gpio_in);
0106     if (ret)
0107         return ret;
0108
0109     ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
0110     if (ret)
0111         return ret;
0112
0113     *value = (u8) be16_to_cpu(st->spi_msg);
0114
0115     return 0;
0116 }
0117
0118 static const struct ad5592r_rw_ops ad5592r_rw_ops = {
0119     .write_dac = ad5592r_write_dac,
0120     .read_adc = ad5592r_read_adc,
0121     .reg_write = ad5592r_reg_write,
0122     .reg_read = ad5592r_reg_read,
0123     .gpio_read = ad5592r_gpio_read,
0124 };
0125
0126 static int ad5592r_spi_probe(struct spi_device *spi)
0127 {
0128     const struct spi_device_id *id = spi_get_device_id(spi);
0129
0130     return ad5592r_probe(&spi->dev, id->name, &ad5592r_rw_ops);
0131 }
0132
0133 static void ad5592r_spi_remove(struct spi_device *spi)
0134 {
0135     ad5592r_remove(&spi->dev);
0136 }
0137
0138 static const struct spi_device_id ad5592r_spi_ids[] = {
0139     { .name = "ad5592r", },
0140     {}
0141 };
0142 MODULE_DEVICE_TABLE(spi, ad5592r_spi_ids);
0143
0144 static const struct of_device_id ad5592r_of_match[] = {
0145     { .compatible = "adi,ad5592r", },
0146     {},
0147 };
0148 MODULE_DEVICE_TABLE(of, ad5592r_of_match);
0149
0150 static const struct acpi_device_id ad5592r_acpi_match[] = {
0151     {"ADS5592", },
0152     { },
0153 };
0154 MODULE_DEVICE_TABLE(acpi, ad5592r_acpi_match);
0155
0156 static struct spi_driver ad5592r_spi_driver = {
0157     .driver = {
0158         .name = "ad5592r",
0159         .of_match_table = ad5592r_of_match,
0160         .acpi_match_table = ad5592r_acpi_match,
0161     },
0162     .probe = ad5592r_spi_probe,
0163     .remove = ad5592r_spi_remove,
0164     .id_table = ad5592r_spi_ids,
0165 };
0166 module_spi_driver(ad5592r_spi_driver);
0167
0168 MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
0169 MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
0170 MODULE_LICENSE("GPL v2");
0171 MODULE_IMPORT_NS(IIO_AD5592R);