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-rw-r--r--drivers/iio/adc/ad7606_spi.c365
1 files changed, 365 insertions, 0 deletions
diff --git a/drivers/iio/adc/ad7606_spi.c b/drivers/iio/adc/ad7606_spi.c
new file mode 100644
index 000000000..263a778bc
--- /dev/null
+++ b/drivers/iio/adc/ad7606_spi.c
@@ -0,0 +1,365 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AD7606 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+#include <linux/err.h>
+
+#include <linux/iio/iio.h>
+#include "ad7606.h"
+
+#define MAX_SPI_FREQ_HZ 23500000 /* VDRIVE above 4.75 V */
+
+#define AD7616_CONFIGURATION_REGISTER 0x02
+#define AD7616_OS_MASK GENMASK(4, 2)
+#define AD7616_BURST_MODE BIT(6)
+#define AD7616_SEQEN_MODE BIT(5)
+#define AD7616_RANGE_CH_A_ADDR_OFF 0x04
+#define AD7616_RANGE_CH_B_ADDR_OFF 0x06
+/*
+ * Range of channels from a group are stored in 2 registers.
+ * 0, 1, 2, 3 in a register followed by 4, 5, 6, 7 in second register.
+ * For channels from second group(8-15) the order is the same, only with
+ * an offset of 2 for register address.
+ */
+#define AD7616_RANGE_CH_ADDR(ch) ((ch) >> 2)
+/* The range of the channel is stored in 2 bits */
+#define AD7616_RANGE_CH_MSK(ch) (0b11 << (((ch) & 0b11) * 2))
+#define AD7616_RANGE_CH_MODE(ch, mode) ((mode) << ((((ch) & 0b11)) * 2))
+
+#define AD7606_CONFIGURATION_REGISTER 0x02
+#define AD7606_SINGLE_DOUT 0x00
+
+/*
+ * Range for AD7606B channels are stored in registers starting with address 0x3.
+ * Each register stores range for 2 channels(4 bits per channel).
+ */
+#define AD7606_RANGE_CH_MSK(ch) (GENMASK(3, 0) << (4 * ((ch) & 0x1)))
+#define AD7606_RANGE_CH_MODE(ch, mode) \
+ ((GENMASK(3, 0) & mode) << (4 * ((ch) & 0x1)))
+#define AD7606_RANGE_CH_ADDR(ch) (0x03 + ((ch) >> 1))
+#define AD7606_OS_MODE 0x08
+
+static const struct iio_chan_spec ad7616_sw_channels[] = {
+ IIO_CHAN_SOFT_TIMESTAMP(16),
+ AD7616_CHANNEL(0),
+ AD7616_CHANNEL(1),
+ AD7616_CHANNEL(2),
+ AD7616_CHANNEL(3),
+ AD7616_CHANNEL(4),
+ AD7616_CHANNEL(5),
+ AD7616_CHANNEL(6),
+ AD7616_CHANNEL(7),
+ AD7616_CHANNEL(8),
+ AD7616_CHANNEL(9),
+ AD7616_CHANNEL(10),
+ AD7616_CHANNEL(11),
+ AD7616_CHANNEL(12),
+ AD7616_CHANNEL(13),
+ AD7616_CHANNEL(14),
+ AD7616_CHANNEL(15),
+};
+
+static const struct iio_chan_spec ad7606b_sw_channels[] = {
+ IIO_CHAN_SOFT_TIMESTAMP(8),
+ AD7616_CHANNEL(0),
+ AD7616_CHANNEL(1),
+ AD7616_CHANNEL(2),
+ AD7616_CHANNEL(3),
+ AD7616_CHANNEL(4),
+ AD7616_CHANNEL(5),
+ AD7616_CHANNEL(6),
+ AD7616_CHANNEL(7),
+};
+
+static const unsigned int ad7606B_oversampling_avail[9] = {
+ 1, 2, 4, 8, 16, 32, 64, 128, 256
+};
+
+static u16 ad7616_spi_rd_wr_cmd(int addr, char isWriteOp)
+{
+ /*
+ * The address of register consist of one w/r bit
+ * 6 bits of address followed by one reserved bit.
+ */
+ return ((addr & 0x7F) << 1) | ((isWriteOp & 0x1) << 7);
+}
+
+static u16 ad7606B_spi_rd_wr_cmd(int addr, char is_write_op)
+{
+ /*
+ * The address of register consists of one bit which
+ * specifies a read command placed in bit 6, followed by
+ * 6 bits of address.
+ */
+ return (addr & 0x3F) | (((~is_write_op) & 0x1) << 6);
+}
+
+static int ad7606_spi_read_block(struct device *dev,
+ int count, void *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ int i, ret;
+ unsigned short *data = buf;
+ __be16 *bdata = buf;
+
+ ret = spi_read(spi, buf, count * 2);
+ if (ret < 0) {
+ dev_err(&spi->dev, "SPI read error\n");
+ return ret;
+ }
+
+ for (i = 0; i < count; i++)
+ data[i] = be16_to_cpu(bdata[i]);
+
+ return 0;
+}
+
+static int ad7606_spi_reg_read(struct ad7606_state *st, unsigned int addr)
+{
+ struct spi_device *spi = to_spi_device(st->dev);
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->d16[0],
+ .len = 2,
+ .cs_change = 0,
+ }, {
+ .rx_buf = &st->d16[1],
+ .len = 2,
+ },
+ };
+ int ret;
+
+ st->d16[0] = cpu_to_be16(st->bops->rd_wr_cmd(addr, 0) << 8);
+
+ ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(st->d16[1]);
+}
+
+static int ad7606_spi_reg_write(struct ad7606_state *st,
+ unsigned int addr,
+ unsigned int val)
+{
+ struct spi_device *spi = to_spi_device(st->dev);
+
+ st->d16[0] = cpu_to_be16((st->bops->rd_wr_cmd(addr, 1) << 8) |
+ (val & 0x1FF));
+
+ return spi_write(spi, &st->d16[0], sizeof(st->d16[0]));
+}
+
+static int ad7606_spi_write_mask(struct ad7606_state *st,
+ unsigned int addr,
+ unsigned long mask,
+ unsigned int val)
+{
+ int readval;
+
+ readval = st->bops->reg_read(st, addr);
+ if (readval < 0)
+ return readval;
+
+ readval &= ~mask;
+ readval |= val;
+
+ return st->bops->reg_write(st, addr, readval);
+}
+
+static int ad7616_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+ unsigned int ch_addr, mode, ch_index;
+
+
+ /*
+ * Ad7616 has 16 channels divided in group A and group B.
+ * The range of channels from A are stored in registers with address 4
+ * while channels from B are stored in register with address 6.
+ * The last bit from channels determines if it is from group A or B
+ * because the order of channels in iio is 0A, 0B, 1A, 1B...
+ */
+ ch_index = ch >> 1;
+
+ ch_addr = AD7616_RANGE_CH_ADDR(ch_index);
+
+ if ((ch & 0x1) == 0) /* channel A */
+ ch_addr += AD7616_RANGE_CH_A_ADDR_OFF;
+ else /* channel B */
+ ch_addr += AD7616_RANGE_CH_B_ADDR_OFF;
+
+ /* 0b01 for 2.5v, 0b10 for 5v and 0b11 for 10v */
+ mode = AD7616_RANGE_CH_MODE(ch_index, ((val + 1) & 0b11));
+ return st->bops->write_mask(st, ch_addr, AD7616_RANGE_CH_MSK(ch_index),
+ mode);
+}
+
+static int ad7616_write_os_sw(struct iio_dev *indio_dev, int val)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ return st->bops->write_mask(st, AD7616_CONFIGURATION_REGISTER,
+ AD7616_OS_MASK, val << 2);
+}
+
+static int ad7606_write_scale_sw(struct iio_dev *indio_dev, int ch, int val)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ return ad7606_spi_write_mask(st,
+ AD7606_RANGE_CH_ADDR(ch),
+ AD7606_RANGE_CH_MSK(ch),
+ AD7606_RANGE_CH_MODE(ch, val));
+}
+
+static int ad7606_write_os_sw(struct iio_dev *indio_dev, int val)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ return ad7606_spi_reg_write(st, AD7606_OS_MODE, val);
+}
+
+static int ad7616_sw_mode_config(struct iio_dev *indio_dev)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+
+ /*
+ * Scale can be configured individually for each channel
+ * in software mode.
+ */
+ indio_dev->channels = ad7616_sw_channels;
+
+ st->write_scale = ad7616_write_scale_sw;
+ st->write_os = &ad7616_write_os_sw;
+
+ /* Activate Burst mode and SEQEN MODE */
+ return st->bops->write_mask(st,
+ AD7616_CONFIGURATION_REGISTER,
+ AD7616_BURST_MODE | AD7616_SEQEN_MODE,
+ AD7616_BURST_MODE | AD7616_SEQEN_MODE);
+}
+
+static int ad7606B_sw_mode_config(struct iio_dev *indio_dev)
+{
+ struct ad7606_state *st = iio_priv(indio_dev);
+ unsigned long os[3] = {1};
+
+ /*
+ * Software mode is enabled when all three oversampling
+ * pins are set to high. If oversampling gpios are defined
+ * in the device tree, then they need to be set to high,
+ * otherwise, they must be hardwired to VDD
+ */
+ if (st->gpio_os) {
+ gpiod_set_array_value(ARRAY_SIZE(os),
+ st->gpio_os->desc, st->gpio_os->info, os);
+ }
+ /* OS of 128 and 256 are available only in software mode */
+ st->oversampling_avail = ad7606B_oversampling_avail;
+ st->num_os_ratios = ARRAY_SIZE(ad7606B_oversampling_avail);
+
+ st->write_scale = ad7606_write_scale_sw;
+ st->write_os = &ad7606_write_os_sw;
+
+ /* Configure device spi to output on a single channel */
+ st->bops->reg_write(st,
+ AD7606_CONFIGURATION_REGISTER,
+ AD7606_SINGLE_DOUT);
+
+ /*
+ * Scale can be configured individually for each channel
+ * in software mode.
+ */
+ indio_dev->channels = ad7606b_sw_channels;
+
+ return 0;
+}
+
+static const struct ad7606_bus_ops ad7606_spi_bops = {
+ .read_block = ad7606_spi_read_block,
+};
+
+static const struct ad7606_bus_ops ad7616_spi_bops = {
+ .read_block = ad7606_spi_read_block,
+ .reg_read = ad7606_spi_reg_read,
+ .reg_write = ad7606_spi_reg_write,
+ .write_mask = ad7606_spi_write_mask,
+ .rd_wr_cmd = ad7616_spi_rd_wr_cmd,
+ .sw_mode_config = ad7616_sw_mode_config,
+};
+
+static const struct ad7606_bus_ops ad7606B_spi_bops = {
+ .read_block = ad7606_spi_read_block,
+ .reg_read = ad7606_spi_reg_read,
+ .reg_write = ad7606_spi_reg_write,
+ .write_mask = ad7606_spi_write_mask,
+ .rd_wr_cmd = ad7606B_spi_rd_wr_cmd,
+ .sw_mode_config = ad7606B_sw_mode_config,
+};
+
+static int ad7606_spi_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ const struct ad7606_bus_ops *bops;
+
+ switch (id->driver_data) {
+ case ID_AD7616:
+ bops = &ad7616_spi_bops;
+ break;
+ case ID_AD7606B:
+ bops = &ad7606B_spi_bops;
+ break;
+ default:
+ bops = &ad7606_spi_bops;
+ break;
+ }
+
+ return ad7606_probe(&spi->dev, spi->irq, NULL,
+ id->name, id->driver_data,
+ bops);
+}
+
+static const struct spi_device_id ad7606_id_table[] = {
+ { "ad7605-4", ID_AD7605_4 },
+ { "ad7606-4", ID_AD7606_4 },
+ { "ad7606-6", ID_AD7606_6 },
+ { "ad7606-8", ID_AD7606_8 },
+ { "ad7606b", ID_AD7606B },
+ { "ad7616", ID_AD7616 },
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad7606_id_table);
+
+static const struct of_device_id ad7606_of_match[] = {
+ { .compatible = "adi,ad7605-4" },
+ { .compatible = "adi,ad7606-4" },
+ { .compatible = "adi,ad7606-6" },
+ { .compatible = "adi,ad7606-8" },
+ { .compatible = "adi,ad7606b" },
+ { .compatible = "adi,ad7616" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ad7606_of_match);
+
+static struct spi_driver ad7606_driver = {
+ .driver = {
+ .name = "ad7606",
+ .of_match_table = ad7606_of_match,
+ .pm = AD7606_PM_OPS,
+ },
+ .probe = ad7606_spi_probe,
+ .id_table = ad7606_id_table,
+};
+module_spi_driver(ad7606_driver);
+
+MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(IIO_AD7606);