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1// SPDX-License-Identifier: GPL-2.02/*3 *4 * x9250.c -- Renesas X9250 potentiometers IIO driver5 *6 * Copyright 2023 CS GROUP France7 *8 * Author: Herve Codina <herve.codina@bootlin.com>9 */10 11#include <linux/delay.h>12#include <linux/gpio/consumer.h>13#include <linux/iio/iio.h>14#include <linux/limits.h>15#include <linux/module.h>16#include <linux/regulator/consumer.h>17#include <linux/slab.h>18#include <linux/spi/spi.h>19 20struct x9250_cfg {21 const char *name;22 int kohms;23};24 25struct x9250 {26 struct spi_device *spi;27 const struct x9250_cfg *cfg;28 struct gpio_desc *wp_gpio;29};30 31#define X9250_ID 0x5032#define X9250_CMD_RD_WCR(_p) (0x90 | (_p))33#define X9250_CMD_WR_WCR(_p) (0xa0 | (_p))34 35static int x9250_write8(struct x9250 *x9250, u8 cmd, u8 val)36{37 u8 txbuf[3];38 39 txbuf[0] = X9250_ID;40 txbuf[1] = cmd;41 txbuf[2] = val;42 43 return spi_write_then_read(x9250->spi, txbuf, ARRAY_SIZE(txbuf), NULL, 0);44}45 46static int x9250_read8(struct x9250 *x9250, u8 cmd, u8 *val)47{48 u8 txbuf[2];49 50 txbuf[0] = X9250_ID;51 txbuf[1] = cmd;52 53 return spi_write_then_read(x9250->spi, txbuf, ARRAY_SIZE(txbuf), val, 1);54}55 56#define X9250_CHANNEL(ch) { \57 .type = IIO_RESISTANCE, \58 .indexed = 1, \59 .output = 1, \60 .channel = (ch), \61 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \62 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \63 .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW), \64}65 66static const struct iio_chan_spec x9250_channels[] = {67 X9250_CHANNEL(0),68 X9250_CHANNEL(1),69 X9250_CHANNEL(2),70 X9250_CHANNEL(3),71};72 73static int x9250_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,74 int *val, int *val2, long mask)75{76 struct x9250 *x9250 = iio_priv(indio_dev);77 int ch = chan->channel;78 int ret;79 u8 v;80 81 switch (mask) {82 case IIO_CHAN_INFO_RAW:83 ret = x9250_read8(x9250, X9250_CMD_RD_WCR(ch), &v);84 if (ret)85 return ret;86 *val = v;87 return IIO_VAL_INT;88 89 case IIO_CHAN_INFO_SCALE:90 *val = 1000 * x9250->cfg->kohms;91 *val2 = U8_MAX;92 return IIO_VAL_FRACTIONAL;93 }94 95 return -EINVAL;96}97 98static int x9250_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,99 const int **vals, int *type, int *length, long mask)100{101 static const int range[] = {0, 1, 255}; /* min, step, max */102 103 switch (mask) {104 case IIO_CHAN_INFO_RAW:105 *length = ARRAY_SIZE(range);106 *vals = range;107 *type = IIO_VAL_INT;108 return IIO_AVAIL_RANGE;109 }110 111 return -EINVAL;112}113 114static int x9250_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,115 int val, int val2, long mask)116{117 struct x9250 *x9250 = iio_priv(indio_dev);118 int ch = chan->channel;119 int ret;120 121 if (mask != IIO_CHAN_INFO_RAW)122 return -EINVAL;123 124 if (val > U8_MAX || val < 0)125 return -EINVAL;126 127 gpiod_set_value_cansleep(x9250->wp_gpio, 0);128 ret = x9250_write8(x9250, X9250_CMD_WR_WCR(ch), val);129 gpiod_set_value_cansleep(x9250->wp_gpio, 1);130 131 return ret;132}133 134static const struct iio_info x9250_info = {135 .read_raw = x9250_read_raw,136 .read_avail = x9250_read_avail,137 .write_raw = x9250_write_raw,138};139 140enum x9250_type {141 X9250T,142 X9250U,143};144 145static const struct x9250_cfg x9250_cfg[] = {146 [X9250T] = { .name = "x9250t", .kohms = 100, },147 [X9250U] = { .name = "x9250u", .kohms = 50, },148};149 150static const char *const x9250_regulator_names[] = {151 "vcc",152 "avp",153 "avn",154};155 156static int x9250_probe(struct spi_device *spi)157{158 struct iio_dev *indio_dev;159 struct x9250 *x9250;160 int ret;161 162 ret = devm_regulator_bulk_get_enable(&spi->dev, ARRAY_SIZE(x9250_regulator_names),163 x9250_regulator_names);164 if (ret)165 return dev_err_probe(&spi->dev, ret, "Failed to get regulators\n");166 167 /*168 * The x9250 needs a 5ms maximum delay after the power-supplies are set169 * before performing the first write (1ms for the first read).170 */171 usleep_range(5000, 6000);172 173 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*x9250));174 if (!indio_dev)175 return -ENOMEM;176 177 x9250 = iio_priv(indio_dev);178 x9250->spi = spi;179 x9250->cfg = spi_get_device_match_data(spi);180 x9250->wp_gpio = devm_gpiod_get_optional(&spi->dev, "wp", GPIOD_OUT_LOW);181 if (IS_ERR(x9250->wp_gpio))182 return dev_err_probe(&spi->dev, PTR_ERR(x9250->wp_gpio),183 "failed to get wp gpio\n");184 185 indio_dev->info = &x9250_info;186 indio_dev->channels = x9250_channels;187 indio_dev->num_channels = ARRAY_SIZE(x9250_channels);188 indio_dev->name = x9250->cfg->name;189 190 return devm_iio_device_register(&spi->dev, indio_dev);191}192 193static const struct of_device_id x9250_of_match[] = {194 { .compatible = "renesas,x9250t", .data = &x9250_cfg[X9250T]},195 { .compatible = "renesas,x9250u", .data = &x9250_cfg[X9250U]},196 { }197};198MODULE_DEVICE_TABLE(of, x9250_of_match);199 200static const struct spi_device_id x9250_id_table[] = {201 { "x9250t", (kernel_ulong_t)&x9250_cfg[X9250T] },202 { "x9250u", (kernel_ulong_t)&x9250_cfg[X9250U] },203 { }204};205MODULE_DEVICE_TABLE(spi, x9250_id_table);206 207static struct spi_driver x9250_spi_driver = {208 .driver = {209 .name = "x9250",210 .of_match_table = x9250_of_match,211 },212 .id_table = x9250_id_table,213 .probe = x9250_probe,214};215 216module_spi_driver(x9250_spi_driver);217 218MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");219MODULE_DESCRIPTION("X9250 ALSA SoC driver");220MODULE_LICENSE("GPL");221