[PATCH v2] drivers: iio: adc: add support for ad777x family

From: ranechita
Date: Wed May 29 2024 - 11:04:42 EST


Added support for ad7770,ad7771,ad7779 ADCs. The
data is streamed only on the spi-mode, without
using the data lines.

Signed-off-by: ranechita <ramona.nechita@xxxxxxxxxx>
---
drivers/iio/adc/Kconfig | 11 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ad7779.c | 951 +++++++++++++++++++++++++++++++++++++++
3 files changed, 963 insertions(+)
create mode 100644 drivers/iio/adc/ad7779.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 0d9282fa67f5..3e42cbc365d7 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -206,6 +206,17 @@ config AD7768_1
To compile this driver as a module, choose M here: the module will be
called ad7768-1.

+config AD7779
+ tristate "Analog Devices AD7779 ADC driver"
+ depends on SPI
+ select IIO_BUFFER
+ help
+ Say yes here to build support for Analog Devices AD7779 SPI
+ analog to digital converter (ADC)
+
+ To compile this driver as a module, choose M here: the module will be
+ called ad7779.
+
config AD7780
tristate "Analog Devices AD7780 and similar ADCs driver"
depends on SPI
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index b3c434722364..e25997e926bb 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_AD7606_IFACE_SPI) += ad7606_spi.o
obj-$(CONFIG_AD7606) += ad7606.o
obj-$(CONFIG_AD7766) += ad7766.o
obj-$(CONFIG_AD7768_1) += ad7768-1.o
+obj-$(CONFIG_AD7779) += ad7779.o
obj-$(CONFIG_AD7780) += ad7780.o
obj-$(CONFIG_AD7791) += ad7791.o
obj-$(CONFIG_AD7793) += ad7793.o
diff --git a/drivers/iio/adc/ad7779.c b/drivers/iio/adc/ad7779.c
new file mode 100644
index 000000000000..089e352e2d40
--- /dev/null
+++ b/drivers/iio/adc/ad7779.c
@@ -0,0 +1,951 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AD777X ADC
+ *
+ * Copyright 2023 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/clk.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/string.h>
+#include <linux/units.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/sysfs.h>
+
+#define AD777X_SPI_READ_CMD BIT(7)
+
+#define AD777X_DISABLE_SD BIT(7)
+
+#define AD777X_REG_CH_DISABLE 0x08
+#define AD777X_REG_CH_SYNC_OFFSET(ch) (0x09 + (ch))
+#define AD777X_REG_CH_CONFIG(ch) (0x00 + (ch))
+#define AD777X_REG_GENERAL_USER_CONFIG_1 0x11
+#define AD777X_REG_GENERAL_USER_CONFIG_2 0x12
+#define AD777X_REG_GENERAL_USER_CONFIG_3 0x13
+#define AD777X_REG_DOUT_FORMAT 0x14
+#define AD777X_REG_ADC_MUX_CONFIG 0x15
+#define AD777X_REG_GPIO_CONFIG 0x17
+#define AD777X_REG_BUFFER_CONFIG_1 0x19
+#define AD777X_REG_GLOBAL_MUX_CONFIG 0x16
+#define AD777X_REG_BUFFER_CONFIG_2 0x1A
+#define AD777X_REG_GPIO_DATA 0x18
+#define AD777X_REG_CH_OFFSET_UPPER_BYTE(ch) (0x1C + (ch) * 6)
+#define AD777X_REG_CH_OFFSET_LOWER_BYTE(ch) (0x1E + (ch) * 6)
+#define AD777X_REG_CH_GAIN_UPPER_BYTE(ch) (0x1F + (ch) * 6)
+#define AD777X_REG_CH_OFFSET_MID_BYTE(ch) (0x1D + (ch) * 6)
+#define AD777X_REG_CH_GAIN_MID_BYTE(ch) (0x20 + (ch) * 6)
+#define AD777X_REG_CH_ERR_REG(ch) (0x4C + (ch))
+#define AD777X_REG_CH0_1_SAT_ERR 0x54
+#define AD777X_REG_CH_GAIN_LOWER_BYTE(ch) (0x21 + (ch) * 6)
+#define AD777X_REG_CH2_3_SAT_ERR 0x55
+#define AD777X_REG_CH4_5_SAT_ERR 0x56
+#define AD777X_REG_CH6_7_SAT_ERR 0x57
+#define AD777X_REG_CHX_ERR_REG_EN 0x58
+#define AD777X_REG_GEN_ERR_REG_1 0x59
+#define AD777X_REG_GEN_ERR_REG_1_EN 0x5A
+#define AD777X_REG_GEN_ERR_REG_2 0x5B
+#define AD777X_REG_GEN_ERR_REG_2_EN 0x5C
+#define AD777X_REG_STATUS_REG_1 0x5D
+#define AD777X_REG_STATUS_REG_2 0x5E
+#define AD777X_REG_STATUS_REG_3 0x5F
+#define AD777X_REG_SRC_N_MSB 0x60
+#define AD777X_REG_SRC_N_LSB 0x61
+#define AD777X_REG_SRC_IF_MSB 0x62
+#define AD777X_REG_SRC_IF_LSB 0x63
+#define AD777X_REG_SRC_UPDATE 0x64
+
+#define AD777X_FILTER_MSK BIT(6)
+#define AD777X_MOD_POWERMODE_MSK BIT(6)
+#define AD777X_MOD_PDB_REFOUT_MSK BIT(4)
+#define AD777X_MOD_SPI_EN_MSK BIT(4)
+
+/* AD777X_REG_DOUT_FORMAT */
+#define AD777X_DOUT_FORMAT_MSK GENMASK(7, 6)
+#define AD777X_DOUT_HEADER_FORMAT BIT(5)
+#define AD777X_DCLK_CLK_DIV_MSK GENMASK(3, 1)
+
+#define AD777X_REFMUX_CTRL_MSK GENMASK(7, 6)
+#define AD777X_SPI_CRC_EN_MSK BIT(0)
+
+#define AD777X_MAXCLK_LOWPOWER 4096000
+#define AD777X_NUM_CHANNELS 8
+#define AD777X_RESET_BUF_SIZE 8
+
+#define AD777X_LOWPOWER_DIV 512
+#define AD777X_HIGHPOWER_DIV 2048
+
+#define AD777X_SINC3_MAXFREQ (16 * HZ_PER_KHZ)
+#define AD777X_SINC5_MAXFREQ (128 * HZ_PER_KHZ)
+
+#define AD777X_DEFAULT_SAMPLING_FREQ (8 * HZ_PER_KHZ)
+#define AD777X_DEFAULT_SAMPLING_2LINE (4 * HZ_PER_KHZ)
+#define AD777X_DEFAULT_SAMPLING_1LINE (2 * HZ_PER_KHZ)
+
+#define AD777X_SPIMODE_MAX_SAMP_FREQ (16 * HZ_PER_KHZ)
+
+#define GAIN_REL 0x555555
+#define AD777X_FREQ_MSB_MSK GENMASK(15, 8)
+#define AD777X_FREQ_LSB_MSK GENMASK(7, 0)
+#define AD777X_UPPER GENMASK(23, 16)
+#define AD777X_MID GENMASK(15, 8)
+#define AD777X_LOWER GENMASK(7, 0)
+
+#define AD777X_REG_READ_MSK GENMASK(6, 0)
+
+#define AD777X_CRC8_POLY 0x07
+DECLARE_CRC8_TABLE(ad777x_crc8_table);
+
+enum ad777x_filter {
+ AD777X_SINC3,
+ AD777X_SINC5,
+};
+
+enum ad777x_variant {
+ ad7770,
+ ad7771,
+ ad7779,
+};
+
+enum ad777x_power_mode {
+ AD777X_LOW_POWER,
+ AD777X_HIGH_POWER,
+};
+
+struct ad777x_chip_info {
+ const char *name;
+ struct iio_chan_spec const *channels;
+};
+
+struct ad777x_state {
+ struct spi_device *spi;
+ const struct ad777x_chip_info *chip_info;
+ struct clk *mclk;
+ struct regulator *vref;
+ unsigned int sampling_freq;
+ enum ad777x_power_mode power_mode;
+ enum ad777x_filter filter_enabled;
+ unsigned int active_ch;
+ unsigned int spidata_mode;
+ unsigned int crc_enabled;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+ u8 reg_rx_buf[3] ____cacheline_aligned;
+ u8 reg_tx_buf[3];
+ __be32 spidata_rx[8];
+ __be32 spidata_tx[8];
+ u8 reset_buf[8];
+};
+
+static const char * const ad777x_filter_type[] = {
+ [AD777X_SINC3] = "sinc3_filter",
+ [AD777X_SINC5] = "sinc5_filter",
+};
+
+static int ad777x_spi_read(struct ad777x_state *st, u8 reg, u8 *rbuf)
+{
+ int ret;
+ int length = 2;
+ u8 crc_buf[2];
+ u8 exp_crc = 0;
+ struct spi_transfer reg_read_tr[] = {
+ {
+ .tx_buf = st->reg_tx_buf,
+ .rx_buf = st->reg_rx_buf,
+ },
+ };
+
+ if (st->crc_enabled)
+ length = 3;
+ reg_read_tr[0].len = length;
+
+ st->reg_tx_buf[0] = AD777X_SPI_READ_CMD | (reg & 0x7F);
+ st->reg_tx_buf[1] = 0;
+ st->reg_tx_buf[2] = crc8(ad777x_crc8_table, st->reg_tx_buf, 2, 0);
+
+ ret = spi_sync_transfer(st->spi, reg_read_tr, ARRAY_SIZE(reg_read_tr));
+ if (ret)
+ return ret;
+
+ crc_buf[0] = AD777X_SPI_READ_CMD | FIELD_GET(AD777X_REG_READ_MSK, reg);
+ crc_buf[1] = st->reg_rx_buf[1];
+ exp_crc = crc8(ad777x_crc8_table, crc_buf, 2, 0);
+ if (st->crc_enabled && exp_crc != st->reg_rx_buf[2]) {
+ dev_err(&st->spi->dev, "Bad CRC %x, expected %x",
+ st->reg_rx_buf[2], exp_crc);
+ return -EINVAL;
+ }
+ *rbuf = st->reg_rx_buf[1];
+
+ return 0;
+}
+
+static int ad777x_spi_write(struct ad777x_state *st, u8 reg, u8 val)
+{
+ int length = 2;
+ struct spi_transfer reg_write_tr[] = {
+ {
+ .tx_buf = st->reg_tx_buf,
+ },
+ };
+
+ if (st->crc_enabled)
+ length = 3;
+ reg_write_tr[0].len = length;
+
+ st->reg_tx_buf[0] = reg & 0x7F;
+ st->reg_tx_buf[1] = val;
+ st->reg_tx_buf[2] = crc8(ad777x_crc8_table, st->reg_tx_buf, 2, 0);
+
+ return spi_sync_transfer(st->spi, reg_write_tr, ARRAY_SIZE(reg_write_tr));
+}
+
+static int ad777x_spi_write_mask(struct ad777x_state *st, u8 reg, u8 mask,
+ u8 val)
+{
+ int ret;
+ u8 regval, data;
+
+ ret = ad777x_spi_read(st, reg, &data);
+ if (ret)
+ return ret;
+
+ regval = data;
+ regval &= ~mask;
+ regval |= val;
+
+ if (regval == data)
+ return 0;
+
+ return ad777x_spi_write(st, reg, regval);
+
+}
+
+static int ad777x_reg_access(struct iio_dev *indio_dev,
+ unsigned int reg,
+ unsigned int writeval,
+ unsigned int *readval)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+
+ if (readval)
+ return ad777x_spi_read(st, reg, (u8 *)readval);
+
+ return ad777x_spi_write(st, reg, writeval);
+}
+
+static int ad777x_set_sampling_frequency(struct ad777x_state *st,
+ unsigned int sampling_freq)
+{
+ int ret;
+ unsigned int dec;
+ unsigned int div;
+ unsigned int decimal;
+ int temp;
+ unsigned int kfreq;
+ u8 msb, lsb;
+
+ if (st->filter_enabled == AD777X_SINC3 &&
+ sampling_freq > AD777X_SINC3_MAXFREQ)
+ return -EINVAL;
+
+ if (st->filter_enabled == AD777X_SINC5 &&
+ sampling_freq > AD777X_SINC5_MAXFREQ)
+ return -EINVAL;
+
+ if (st->spidata_mode == 1 &&
+ sampling_freq > AD777X_SPIMODE_MAX_SAMP_FREQ)
+ return -EINVAL;
+
+ if (st->power_mode == AD777X_LOW_POWER)
+ div = AD777X_LOWPOWER_DIV;
+ else
+ div = AD777X_HIGHPOWER_DIV;
+
+ kfreq = sampling_freq / KILO;
+ dec = div / kfreq;
+
+ lsb = FIELD_GET(AD777X_FREQ_LSB_MSK, dec);
+ msb = FIELD_GET(AD777X_FREQ_MSB_MSK, dec);
+
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_N_LSB, lsb);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_N_MSB, msb);
+ if (ret)
+ return ret;
+
+ if (div % kfreq) {
+ temp = (div * KILO) / kfreq;
+ decimal = ((temp - dec * KILO) << 16) / KILO;
+ lsb = FIELD_GET(AD777X_FREQ_LSB_MSK, decimal);
+ msb = FIELD_GET(AD777X_FREQ_MSB_MSK, decimal);
+
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_IF_LSB, lsb);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_IF_MSB, msb);
+ if (ret)
+ return ret;
+ } else {
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_IF_LSB, 0x0);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_IF_MSB, 0x0);
+ if (ret)
+ return ret;
+ }
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_UPDATE, 0x1);
+ if (ret)
+ return ret;
+ fsleep(15);
+ ret = ad777x_spi_write(st, AD777X_REG_SRC_UPDATE, 0x0);
+ if (ret)
+ return ret;
+ fsleep(15);
+
+ st->sampling_freq = sampling_freq;
+
+ return 0;
+}
+
+static int ad777x_get_filter(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+ u8 temp;
+ int ret;
+
+ ret = ad777x_spi_read(st, AD777X_REG_GENERAL_USER_CONFIG_2, &temp);
+ if (ret)
+ return ret;
+
+ return FIELD_GET(AD777X_FILTER_MSK, temp);
+}
+
+static int ad777x_set_filter(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ unsigned int mode)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = ad777x_spi_write_mask(st,
+ AD777X_REG_GENERAL_USER_CONFIG_2,
+ AD777X_FILTER_MSK,
+ FIELD_PREP(AD777X_FILTER_MSK, mode));
+ if (ret < 0)
+ return ret;
+
+ ret = ad777x_set_sampling_frequency(st, st->sampling_freq);
+ if (ret < 0)
+ return ret;
+
+ st->filter_enabled = mode;
+
+ return 0;
+}
+
+static int ad777x_get_calibscale(struct ad777x_state *st, int channel)
+{
+ int ret;
+ u8 low, mid, high;
+
+ ret = ad777x_spi_read(st, AD777X_REG_CH_GAIN_LOWER_BYTE(channel), &low);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_read(st, AD777X_REG_CH_GAIN_MID_BYTE(channel), &mid);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_read(st, AD777X_REG_CH_GAIN_UPPER_BYTE(channel), &high);
+ if (ret)
+ return ret;
+
+ return FIELD_PREP(AD777X_UPPER, high) | FIELD_PREP(AD777X_MID, mid) |
+ FIELD_PREP(AD777X_LOWER, low);
+}
+
+static int ad777x_set_calibscale(struct ad777x_state *st, int channel, int val)
+{
+ int ret;
+ u8 msb, mid, lsb;
+ unsigned int gain;
+ unsigned long long tmp;
+
+ tmp = val * 5592405LL;
+ gain = DIV_ROUND_CLOSEST_ULL(tmp, MEGA);
+ msb = FIELD_GET(AD777X_UPPER, gain);
+ mid = FIELD_GET(AD777X_MID, gain);
+ lsb = FIELD_GET(AD777X_LOWER, gain);
+ ret = ad777x_spi_write(st,
+ AD777X_REG_CH_GAIN_UPPER_BYTE(channel),
+ msb);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write(st,
+ AD777X_REG_CH_GAIN_MID_BYTE(channel),
+ mid);
+ if (ret)
+ return ret;
+ return ad777x_spi_write(st,
+ AD777X_REG_CH_GAIN_LOWER_BYTE(channel),
+ lsb);
+}
+
+static int ad777x_get_calibbias(struct ad777x_state *st, int channel)
+{
+ int ret;
+ u8 low, mid, high;
+
+ ret = ad777x_spi_read(st, AD777X_REG_CH_OFFSET_LOWER_BYTE(channel),
+ &low);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_read(st, AD777X_REG_CH_OFFSET_MID_BYTE(channel), &mid);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_read(st,
+ AD777X_REG_CH_OFFSET_UPPER_BYTE(channel),
+ &high);
+ if (ret)
+ return ret;
+
+ return FIELD_PREP(AD777X_UPPER, high) | FIELD_PREP(AD777X_MID, mid) |
+ FIELD_PREP(AD777X_LOWER, low);
+}
+
+static int ad777x_set_calibbias(struct ad777x_state *st, int channel, int val)
+{
+ int ret;
+ u8 msb, mid, lsb;
+
+ msb = FIELD_GET(AD777X_UPPER, val);
+ mid = FIELD_GET(AD777X_MID, val);
+ lsb = FIELD_GET(AD777X_LOWER, val);
+ ret = ad777x_spi_write(st,
+ AD777X_REG_CH_OFFSET_UPPER_BYTE(channel),
+ msb);
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write(st,
+ AD777X_REG_CH_OFFSET_MID_BYTE(channel),
+ mid);
+ if (ret)
+ return ret;
+ return ad777x_spi_write(st,
+ AD777X_REG_CH_OFFSET_LOWER_BYTE(channel),
+ lsb);
+}
+
+static int ad777x_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_CALIBSCALE:
+ *val = ad777x_get_calibscale(st, chan->channel);
+ iio_device_release_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+ *val2 = GAIN_REL;
+ return IIO_VAL_FRACTIONAL;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ *val = ad777x_get_calibbias(st, chan->channel);
+ iio_device_release_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = st->sampling_freq;
+ iio_device_release_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+ return IIO_VAL_INT;
+ }
+
+ iio_device_release_direct_mode(indio_dev);
+
+ return -EINVAL;
+}
+
+static int ad777x_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_CALIBSCALE:
+ return ad777x_set_calibscale(st, chan->channel, val2);
+ case IIO_CHAN_INFO_CALIBBIAS:
+ return ad777x_set_calibbias(st, chan->channel, val);
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return ad777x_set_sampling_frequency(st, val);
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad777x_update_scan_mode(struct iio_dev *indio_dev,
+ const unsigned long *scan_mask)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+
+ bitmap_copy((unsigned long *)&st->active_ch, scan_mask, AD777X_NUM_CHANNELS);
+
+ return 0;
+}
+
+static int ad777x_buffer_postenable(struct iio_dev *indio_dev)
+{
+ int ret;
+ struct ad777x_state *st = iio_priv(indio_dev);
+
+ ret = ad777x_spi_write_mask(st,
+ AD777X_REG_GENERAL_USER_CONFIG_3,
+ AD777X_MOD_SPI_EN_MSK,
+ FIELD_PREP(AD777X_MOD_SPI_EN_MSK, 1));
+ if (ret)
+ return ret;
+ enable_irq(st->spi->irq);
+
+ return 0;
+}
+
+static int ad777x_buffer_predisable(struct iio_dev *indio_dev)
+{
+ int ret;
+ struct ad777x_state *st = iio_priv(indio_dev);
+
+ disable_irq_nosync(st->spi->irq);
+ ret = ad777x_spi_write(st,
+ AD777X_REG_GENERAL_USER_CONFIG_3,
+ AD777X_DISABLE_SD);
+ return ret;
+}
+
+static irqreturn_t ad777x_irq_handler(int irq, void *data)
+{
+ struct iio_dev *indio_dev = data;
+ struct ad777x_state *st = iio_priv(indio_dev);
+ int ret;
+ __be32 tmp[8];
+ int i;
+ int k = 0;
+
+ struct spi_transfer sd_readback_tr[] = {
+ {
+ .rx_buf = st->spidata_rx,
+ .tx_buf = st->spidata_tx,
+ .len = 32,
+ }
+ };
+
+ if (iio_buffer_enabled(indio_dev)) {
+ st->spidata_tx[0] = AD777X_SPI_READ_CMD;
+ ret = spi_sync_transfer(st->spi, sd_readback_tr,
+ ARRAY_SIZE(sd_readback_tr));
+ if (ret) {
+ dev_err(&st->spi->dev,
+ "spi transfer error in irq handler");
+ return IRQ_HANDLED;
+ }
+ for (i = 0; i < AD777X_NUM_CHANNELS; i++) {
+ if (st->active_ch & BIT(i))
+ tmp[k++] = __be32_to_cpu(st->spidata_rx[i]);
+ }
+ iio_push_to_buffers(indio_dev, &tmp[0]);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int ad777x_reset(struct iio_dev *indio_dev, struct gpio_desc *reset_gpio)
+{
+ struct ad777x_state *st = iio_priv(indio_dev);
+ int ret;
+ struct spi_transfer reg_read_tr[] = {
+ {
+ .tx_buf = st->reset_buf,
+ .len = 8,
+ },
+ };
+
+ memset(st->reset_buf, 0xff, sizeof(st->reset_buf));
+
+ if (reset_gpio) {
+ gpiod_set_value(reset_gpio, 1);
+ fsleep(230);
+ return 0;
+ }
+
+ ret = spi_sync_transfer(st->spi, reg_read_tr,
+ ARRAY_SIZE(reg_read_tr));
+ if (ret)
+ return ret;
+
+ fsleep(230);
+
+ return 0;
+}
+
+static const struct iio_info ad777x_info = {
+ .read_raw = ad777x_read_raw,
+ .write_raw = ad777x_write_raw,
+ .debugfs_reg_access = &ad777x_reg_access,
+ .update_scan_mode = &ad777x_update_scan_mode,
+};
+
+static const struct iio_enum ad777x_filter_enum = {
+ .items = ad777x_filter_type,
+ .num_items = ARRAY_SIZE(ad777x_filter_type),
+ .get = ad777x_get_filter,
+ .set = ad777x_set_filter,
+};
+
+static const struct iio_chan_spec_ext_info ad777x_ext_filter[] = {
+ IIO_ENUM("filter_type", IIO_SHARED_BY_ALL, &ad777x_filter_enum),
+ IIO_ENUM_AVAILABLE("filter_type", IIO_SHARED_BY_ALL,
+ &ad777x_filter_enum),
+ { }
+};
+
+#define AD777x_CHAN_S(index, _ext_info) \
+ { \
+ .type = IIO_VOLTAGE, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_CALIBSCALE) | \
+ BIT(IIO_CHAN_INFO_CALIBBIAS), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .address = (index), \
+ .indexed = 1, \
+ .channel = (index), \
+ .scan_index = (index), \
+ .ext_info = (_ext_info), \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 24, \
+ .storagebits = 32, \
+ }, \
+ }
+
+#define AD777x_CHAN_NO_FILTER_S(index) \
+ AD777x_CHAN_S(index, NULL)
+
+#define AD777x_CHAN_FILTER_S(index) \
+ AD777x_CHAN_S(index, ad777x_ext_filter)
+
+static const struct iio_chan_spec ad777x_channels[] = {
+ AD777x_CHAN_NO_FILTER_S(0),
+ AD777x_CHAN_NO_FILTER_S(1),
+ AD777x_CHAN_NO_FILTER_S(2),
+ AD777x_CHAN_NO_FILTER_S(3),
+ AD777x_CHAN_NO_FILTER_S(4),
+ AD777x_CHAN_NO_FILTER_S(5),
+ AD777x_CHAN_NO_FILTER_S(6),
+ AD777x_CHAN_NO_FILTER_S(7),
+};
+
+static const struct iio_chan_spec ad777x_channels_filter[] = {
+ AD777x_CHAN_FILTER_S(0),
+ AD777x_CHAN_FILTER_S(1),
+ AD777x_CHAN_FILTER_S(2),
+ AD777x_CHAN_FILTER_S(3),
+ AD777x_CHAN_FILTER_S(4),
+ AD777x_CHAN_FILTER_S(5),
+ AD777x_CHAN_FILTER_S(6),
+ AD777x_CHAN_FILTER_S(7),
+};
+
+const struct iio_buffer_setup_ops ad777x_buffer_setup_ops = {
+ .postenable = ad777x_buffer_postenable,
+ .predisable = ad777x_buffer_predisable,
+};
+
+static void ad777x_clk_disable(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
+static void ad777x_reg_disable(void *data)
+{
+ regulator_disable(data);
+}
+
+static int ad777x_register(struct ad777x_state *st, struct iio_dev *indio_dev)
+{
+ int ret;
+ struct device *dev = &st->spi->dev;
+
+ indio_dev->name = st->chip_info->name;
+ indio_dev->info = &ad777x_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = st->chip_info->channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad777x_channels);
+
+ ret = devm_request_threaded_irq(dev, st->spi->irq, NULL,
+ ad777x_irq_handler, IRQF_ONESHOT,
+ indio_dev->name, indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "request irq %d failed\n",
+ st->spi->irq);
+
+ ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev,
+ &ad777x_buffer_setup_ops,
+ NULL);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "setup buffer failed\n");
+
+ ret = ad777x_spi_write_mask(st, AD777X_REG_DOUT_FORMAT,
+ AD777X_DCLK_CLK_DIV_MSK,
+ FIELD_PREP(AD777X_DCLK_CLK_DIV_MSK, 7));
+ if (ret)
+ return ret;
+ st->spidata_mode = 1;
+
+ disable_irq_nosync(st->spi->irq);
+
+ return devm_iio_device_register(&st->spi->dev, indio_dev);
+}
+
+static int ad777x_powerup(struct ad777x_state *st, struct gpio_desc *start_gpio)
+{
+ int ret;
+
+ ret = ad777x_spi_write_mask(st, AD777X_REG_GENERAL_USER_CONFIG_1,
+ AD777X_MOD_POWERMODE_MSK,
+ FIELD_PREP(AD777X_MOD_POWERMODE_MSK, 1));
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write_mask(st, AD777X_REG_GENERAL_USER_CONFIG_1,
+ AD777X_MOD_PDB_REFOUT_MSK,
+ FIELD_PREP(AD777X_MOD_PDB_REFOUT_MSK, 1));
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write_mask(st, AD777X_REG_DOUT_FORMAT,
+ AD777X_DCLK_CLK_DIV_MSK,
+ FIELD_PREP(AD777X_DCLK_CLK_DIV_MSK, 1));
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write_mask(st, AD777X_REG_ADC_MUX_CONFIG,
+ AD777X_REFMUX_CTRL_MSK,
+ FIELD_PREP(AD777X_REFMUX_CTRL_MSK, 1));
+ if (ret)
+ return ret;
+ ret = ad777x_spi_write_mask(st, AD777X_REG_GEN_ERR_REG_1_EN,
+ AD777X_SPI_CRC_EN_MSK,
+ FIELD_PREP(AD777X_SPI_CRC_EN_MSK, 1));
+ if (ret)
+ return ret;
+
+ st->power_mode = AD777X_HIGH_POWER;
+ st->crc_enabled = true;
+ ret = ad777x_set_sampling_frequency(st, AD777X_DEFAULT_SAMPLING_FREQ);
+ if (ret)
+ return ret;
+
+ gpiod_set_value(start_gpio, 0);
+ fsleep(15);
+ gpiod_set_value(start_gpio, 1);
+ fsleep(15);
+ gpiod_set_value(start_gpio, 0);
+ fsleep(15);
+
+ return 0;
+}
+
+static int ad777x_probe(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev;
+ struct ad777x_state *st;
+ struct gpio_desc *reset_gpio;
+ struct gpio_desc *start_gpio;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+
+ st->vref = devm_regulator_get_optional(&spi->dev, "vref");
+ if (IS_ERR(st->vref))
+ return PTR_ERR(st->vref);
+
+ ret = regulator_enable(st->vref);
+ if (ret)
+ return ret;
+
+ ret = devm_add_action_or_reset(&spi->dev, ad777x_reg_disable,
+ st->vref);
+ if (ret)
+ return ret;
+
+ st->mclk = devm_clk_get(&spi->dev, "mclk");
+ if (IS_ERR(st->mclk))
+ return PTR_ERR(st->mclk);
+
+ ret = clk_prepare_enable(st->mclk);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_add_action_or_reset(&spi->dev, ad777x_clk_disable,
+ st->mclk);
+ if (ret)
+ return ret;
+
+ reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(reset_gpio))
+ return PTR_ERR(reset_gpio);
+
+ start_gpio = devm_gpiod_get(&spi->dev, "start", GPIOD_OUT_HIGH);
+ if (IS_ERR(start_gpio))
+ return PTR_ERR(start_gpio);
+
+ crc8_populate_msb(ad777x_crc8_table, AD777X_CRC8_POLY);
+ st->spi = spi;
+
+ st->chip_info = spi_get_device_match_data(spi);
+ if (!st->chip_info)
+ return -ENODEV;
+
+ ret = ad777x_reset(indio_dev, start_gpio);
+ if (ret)
+ return ret;
+
+ ad777x_powerup(st, start_gpio);
+ if (ret)
+ return ret;
+
+ if (spi->irq)
+ ret = ad777x_register(st, indio_dev);
+
+ return ret;
+}
+
+static int __maybe_unused ad777x_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad777x_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = ad777x_spi_write_mask(st, AD777X_REG_GENERAL_USER_CONFIG_1,
+ AD777X_MOD_POWERMODE_MSK,
+ FIELD_PREP(AD777X_MOD_POWERMODE_MSK,
+ AD777X_LOW_POWER));
+ if (ret)
+ return ret;
+
+ st->power_mode = AD777X_LOW_POWER;
+ return 0;
+}
+
+static int __maybe_unused ad777x_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ad777x_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = ad777x_spi_write_mask(st, AD777X_REG_GENERAL_USER_CONFIG_1,
+ AD777X_MOD_POWERMODE_MSK,
+ FIELD_PREP(AD777X_MOD_POWERMODE_MSK,
+ AD777X_HIGH_POWER));
+ if (ret)
+ return ret;
+
+ st->power_mode = AD777X_HIGH_POWER;
+
+ return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(ad777x_pm_ops, ad777x_suspend, ad777x_resume);
+
+static const struct ad777x_chip_info ad7770_chip_info = {
+ .name = "ad7770",
+ .channels = ad777x_channels,
+};
+
+static const struct ad777x_chip_info ad7771_chip_info = {
+ .name = "ad7771",
+ .channels = ad777x_channels_filter,
+};
+
+static const struct ad777x_chip_info ad7779_chip_info = {
+ .name = "ad7779",
+ .channels = ad777x_channels,
+};
+
+static const struct spi_device_id ad777x_id[] = {
+ {
+ .name = "ad7770",
+ .driver_data = (__kernel_ulong_t)&ad7770_chip_info
+ },
+ {
+ .name = "ad7771",
+ .driver_data = (__kernel_ulong_t)&ad7771_chip_info
+ },
+ {
+ .name = "ad7779",
+ .driver_data = (__kernel_ulong_t)&ad7779_chip_info
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, ad777x_id);
+
+static const struct of_device_id ad777x_of_table[] = {
+ {
+ .compatible = "adi,ad7770",
+ .data = &ad7770_chip_info,
+ },
+ {
+ .compatible = "adi,ad7771",
+ .data = &ad7771_chip_info,
+ },
+ {
+ .compatible = "adi,ad7779",
+ .data = &ad7779_chip_info,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad777x_of_table);
+
+static struct spi_driver ad777x_driver = {
+ .driver = {
+ .name = "ad777x",
+ .pm = pm_sleep_ptr(&ad777x_pm_ops),
+ .of_match_table = ad777x_of_table,
+ },
+ .probe = ad777x_probe,
+ .id_table = ad777x_id,
+};
+module_spi_driver(ad777x_driver);
+
+MODULE_AUTHOR("Ramona Alexandra Nechita <ramona.nechita@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices AD777X ADC");
+MODULE_LICENSE("GPL");
--
2.43.0