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1// SPDX-License-Identifier: GPL-2.02/*3 * AD7606 SPI ADC driver4 *5 * Copyright 2011 Analog Devices Inc.6 */7 8#include <linux/module.h>9#include <linux/spi/spi.h>10#include <linux/types.h>11#include <linux/err.h>12 13#include <linux/iio/iio.h>14#include "ad7606.h"15 16#define MAX_SPI_FREQ_HZ		23500000	/* VDRIVE above 4.75 V */17 18#define AD7616_CONFIGURATION_REGISTER	0x0219#define AD7616_OS_MASK			GENMASK(4, 2)20#define AD7616_BURST_MODE		BIT(6)21#define AD7616_SEQEN_MODE		BIT(5)22#define AD7616_RANGE_CH_A_ADDR_OFF	0x0423#define AD7616_RANGE_CH_B_ADDR_OFF	0x0624/*25 * Range of channels from a group are stored in 2 registers.26 * 0, 1, 2, 3 in a register followed by 4, 5, 6, 7 in second register.27 * For channels from second group(8-15) the order is the same, only with28 * an offset of 2 for register address.29 */30#define AD7616_RANGE_CH_ADDR(ch)	((ch) >> 2)31/* The range of the channel is stored in 2 bits */32#define AD7616_RANGE_CH_MSK(ch)		(0b11 << (((ch) & 0b11) * 2))33#define AD7616_RANGE_CH_MODE(ch, mode)	((mode) << ((((ch) & 0b11)) * 2))34 35#define AD7606_CONFIGURATION_REGISTER	0x0236#define AD7606_SINGLE_DOUT		0x0037 38/*39 * Range for AD7606B channels are stored in registers starting with address 0x3.40 * Each register stores range for 2 channels(4 bits per channel).41 */42#define AD7606_RANGE_CH_MSK(ch)		(GENMASK(3, 0) << (4 * ((ch) & 0x1)))43#define AD7606_RANGE_CH_MODE(ch, mode)	\44	((GENMASK(3, 0) & mode) << (4 * ((ch) & 0x1)))45#define AD7606_RANGE_CH_ADDR(ch)	(0x03 + ((ch) >> 1))46#define AD7606_OS_MODE			0x0847 48static const struct iio_chan_spec ad7616_sw_channels[] = {49	IIO_CHAN_SOFT_TIMESTAMP(16),50	AD7616_CHANNEL(0),51	AD7616_CHANNEL(1),52	AD7616_CHANNEL(2),53	AD7616_CHANNEL(3),54	AD7616_CHANNEL(4),55	AD7616_CHANNEL(5),56	AD7616_CHANNEL(6),57	AD7616_CHANNEL(7),58	AD7616_CHANNEL(8),59	AD7616_CHANNEL(9),60	AD7616_CHANNEL(10),61	AD7616_CHANNEL(11),62	AD7616_CHANNEL(12),63	AD7616_CHANNEL(13),64	AD7616_CHANNEL(14),65	AD7616_CHANNEL(15),66};67 68static const struct iio_chan_spec ad7606b_sw_channels[] = {69	IIO_CHAN_SOFT_TIMESTAMP(8),70	AD7616_CHANNEL(0),71	AD7616_CHANNEL(1),72	AD7616_CHANNEL(2),73	AD7616_CHANNEL(3),74	AD7616_CHANNEL(4),75	AD7616_CHANNEL(5),76	AD7616_CHANNEL(6),77	AD7616_CHANNEL(7),78};79 80static const unsigned int ad7606B_oversampling_avail[9] = {81	1, 2, 4, 8, 16, 32, 64, 128, 25682};83 84static u16 ad7616_spi_rd_wr_cmd(int addr, char isWriteOp)85{86	/*87	 * The address of register consist of one w/r bit88	 * 6 bits of address followed by one reserved bit.89	 */90	return ((addr & 0x7F) << 1) | ((isWriteOp & 0x1) << 7);91}92 93static u16 ad7606B_spi_rd_wr_cmd(int addr, char is_write_op)94{95	/*96	 * The address of register consists of one bit which97	 * specifies a read command placed in bit 6, followed by98	 * 6 bits of address.99	 */100	return (addr & 0x3F) | (((~is_write_op) & 0x1) << 6);101}102 103static int ad7606_spi_read_block(struct device *dev,104				 int count, void *buf)105{106	struct spi_device *spi = to_spi_device(dev);107	int i, ret;108	unsigned short *data = buf;109	__be16 *bdata = buf;110 111	ret = spi_read(spi, buf, count * 2);112	if (ret < 0) {113		dev_err(&spi->dev, "SPI read error\n");114		return ret;115	}116 117	for (i = 0; i < count; i++)118		data[i] = be16_to_cpu(bdata[i]);119 120	return 0;121}122 123static int ad7606_spi_reg_read(struct ad7606_state *st, unsigned int addr)124{125	struct spi_device *spi = to_spi_device(st->dev);126	struct spi_transfer t[] = {127		{128			.tx_buf = &st->d16[0],129			.len = 2,130			.cs_change = 0,131		}, {132			.rx_buf = &st->d16[1],133			.len = 2,134		},135	};136	int ret;137 138	st->d16[0] = cpu_to_be16(st->bops->rd_wr_cmd(addr, 0) << 8);139 140	ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));141	if (ret < 0)142		return ret;143 144	return be16_to_cpu(st->d16[1]);145}146 147static int ad7606_spi_reg_write(struct ad7606_state *st,148				unsigned int addr,149				unsigned int val)150{151	struct spi_device *spi = to_spi_device(st->dev);152 153	st->d16[0] = cpu_to_be16((st->bops->rd_wr_cmd(addr, 1) << 8) |154				  (val & 0x1FF));155 156	return spi_write(spi, &st->d16[0], sizeof(st->d16[0]));157}158 159static int ad7606_spi_write_mask(struct ad7606_state *st,160				 unsigned int addr,161				 unsigned long mask,162				 unsigned int val)163{164	int readval;165 166	readval = st->bops->reg_read(st, addr);167	if (readval < 0)168		return readval;169 170	readval &= ~mask;171	readval |= val;172 173	return st->bops->reg_write(st, addr, readval);174}175 176static int ad7616_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)177{178	struct ad7606_state *st = iio_priv(indio_dev);179	unsigned int ch_addr, mode, ch_index;180 181 182	/*183	 * Ad7616 has 16 channels divided in group A and group B.184	 * The range of channels from A are stored in registers with address 4185	 * while channels from B are stored in register with address 6.186	 * The last bit from channels determines if it is from group A or B187	 * because the order of channels in iio is 0A, 0B, 1A, 1B...188	 */189	ch_index = ch >> 1;190 191	ch_addr = AD7616_RANGE_CH_ADDR(ch_index);192 193	if ((ch & 0x1) == 0) /* channel A */194		ch_addr += AD7616_RANGE_CH_A_ADDR_OFF;195	else	/* channel B */196		ch_addr += AD7616_RANGE_CH_B_ADDR_OFF;197 198	/* 0b01 for 2.5v, 0b10 for 5v and 0b11 for 10v */199	mode = AD7616_RANGE_CH_MODE(ch_index, ((val + 1) & 0b11));200	return st->bops->write_mask(st, ch_addr, AD7616_RANGE_CH_MSK(ch_index),201				     mode);202}203 204static int ad7616_write_os_sw(struct iio_dev *indio_dev, int val)205{206	struct ad7606_state *st = iio_priv(indio_dev);207 208	return st->bops->write_mask(st, AD7616_CONFIGURATION_REGISTER,209				     AD7616_OS_MASK, val << 2);210}211 212static int ad7606_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)213{214	struct ad7606_state *st = iio_priv(indio_dev);215 216	return ad7606_spi_write_mask(st,217				     AD7606_RANGE_CH_ADDR(ch),218				     AD7606_RANGE_CH_MSK(ch),219				     AD7606_RANGE_CH_MODE(ch, val));220}221 222static int ad7606_write_os_sw(struct iio_dev *indio_dev, int val)223{224	struct ad7606_state *st = iio_priv(indio_dev);225 226	return ad7606_spi_reg_write(st, AD7606_OS_MODE, val);227}228 229static int ad7616_sw_mode_config(struct iio_dev *indio_dev)230{231	struct ad7606_state *st = iio_priv(indio_dev);232 233	/*234	 * Scale can be configured individually for each channel235	 * in software mode.236	 */237	indio_dev->channels = ad7616_sw_channels;238 239	st->write_scale = ad7616_write_scale_sw;240	st->write_os = &ad7616_write_os_sw;241 242	/* Activate Burst mode and SEQEN MODE */243	return st->bops->write_mask(st,244			      AD7616_CONFIGURATION_REGISTER,245			      AD7616_BURST_MODE | AD7616_SEQEN_MODE,246			      AD7616_BURST_MODE | AD7616_SEQEN_MODE);247}248 249static int ad7606B_sw_mode_config(struct iio_dev *indio_dev)250{251	struct ad7606_state *st = iio_priv(indio_dev);252	DECLARE_BITMAP(os, 3);253 254	bitmap_fill(os, 3);255	/*256	 * Software mode is enabled when all three oversampling257	 * pins are set to high. If oversampling gpios are defined258	 * in the device tree, then they need to be set to high,259	 * otherwise, they must be hardwired to VDD260	 */261	if (st->gpio_os) {262		gpiod_set_array_value(st->gpio_os->ndescs,263				      st->gpio_os->desc, st->gpio_os->info, os);264	}265	/* OS of 128 and 256 are available only in software mode */266	st->oversampling_avail = ad7606B_oversampling_avail;267	st->num_os_ratios = ARRAY_SIZE(ad7606B_oversampling_avail);268 269	st->write_scale = ad7606_write_scale_sw;270	st->write_os = &ad7606_write_os_sw;271 272	/* Configure device spi to output on a single channel */273	st->bops->reg_write(st,274			    AD7606_CONFIGURATION_REGISTER,275			    AD7606_SINGLE_DOUT);276 277	/*278	 * Scale can be configured individually for each channel279	 * in software mode.280	 */281	indio_dev->channels = ad7606b_sw_channels;282 283	return 0;284}285 286static const struct ad7606_bus_ops ad7606_spi_bops = {287	.read_block = ad7606_spi_read_block,288};289 290static const struct ad7606_bus_ops ad7616_spi_bops = {291	.read_block = ad7606_spi_read_block,292	.reg_read = ad7606_spi_reg_read,293	.reg_write = ad7606_spi_reg_write,294	.write_mask = ad7606_spi_write_mask,295	.rd_wr_cmd = ad7616_spi_rd_wr_cmd,296	.sw_mode_config = ad7616_sw_mode_config,297};298 299static const struct ad7606_bus_ops ad7606B_spi_bops = {300	.read_block = ad7606_spi_read_block,301	.reg_read = ad7606_spi_reg_read,302	.reg_write = ad7606_spi_reg_write,303	.write_mask = ad7606_spi_write_mask,304	.rd_wr_cmd = ad7606B_spi_rd_wr_cmd,305	.sw_mode_config = ad7606B_sw_mode_config,306};307 308static int ad7606_spi_probe(struct spi_device *spi)309{310	const struct spi_device_id *id = spi_get_device_id(spi);311	const struct ad7606_bus_ops *bops;312 313	switch (id->driver_data) {314	case ID_AD7616:315		bops = &ad7616_spi_bops;316		break;317	case ID_AD7606B:318		bops = &ad7606B_spi_bops;319		break;320	default:321		bops = &ad7606_spi_bops;322		break;323	}324 325	return ad7606_probe(&spi->dev, spi->irq, NULL,326			    id->name, id->driver_data,327			    bops);328}329 330static const struct spi_device_id ad7606_id_table[] = {331	{ "ad7605-4", ID_AD7605_4 },332	{ "ad7606-4", ID_AD7606_4 },333	{ "ad7606-6", ID_AD7606_6 },334	{ "ad7606-8", ID_AD7606_8 },335	{ "ad7606b",  ID_AD7606B },336	{ "ad7616",   ID_AD7616 },337	{ }338};339MODULE_DEVICE_TABLE(spi, ad7606_id_table);340 341static const struct of_device_id ad7606_of_match[] = {342	{ .compatible = "adi,ad7605-4" },343	{ .compatible = "adi,ad7606-4" },344	{ .compatible = "adi,ad7606-6" },345	{ .compatible = "adi,ad7606-8" },346	{ .compatible = "adi,ad7606b" },347	{ .compatible = "adi,ad7616" },348	{ }349};350MODULE_DEVICE_TABLE(of, ad7606_of_match);351 352static struct spi_driver ad7606_driver = {353	.driver = {354		.name = "ad7606",355		.of_match_table = ad7606_of_match,356		.pm = AD7606_PM_OPS,357	},358	.probe = ad7606_spi_probe,359	.id_table = ad7606_id_table,360};361module_spi_driver(ad7606_driver);362 363MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");364MODULE_DESCRIPTION("Analog Devices AD7606 ADC");365MODULE_LICENSE("GPL v2");366MODULE_IMPORT_NS(IIO_AD7606);367