--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Analog Devices AD3552R
+ * Digital to Analog converter driver
+ *
+ * Copyright 2021 Analog Devices Inc.
+ */
+#include <asm/unaligned.h>
+#include <linux/device.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+/* Register addresses */
+/* Primary address space */
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_A 0x00
+#define AD3552R_MASK_SOFTWARE_RESET (BIT(7) | BIT(0))
+#define AD3552R_MASK_ADDR_ASCENSION BIT(5)
+#define AD3552R_MASK_SDO_ACTIVE BIT(4)
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_B 0x01
+#define AD3552R_MASK_SINGLE_INST BIT(7)
+#define AD3552R_MASK_SHORT_INSTRUCTION BIT(3)
+#define AD3552R_REG_ADDR_DEVICE_CONFIG 0x02
+#define AD3552R_MASK_DEVICE_STATUS(n) BIT(4 + (n))
+#define AD3552R_MASK_CUSTOM_MODES GENMASK(3, 2)
+#define AD3552R_MASK_OPERATING_MODES GENMASK(1, 0)
+#define AD3552R_REG_ADDR_CHIP_TYPE 0x03
+#define AD3552R_MASK_CLASS GENMASK(7, 0)
+#define AD3552R_REG_ADDR_PRODUCT_ID_L 0x04
+#define AD3552R_REG_ADDR_PRODUCT_ID_H 0x05
+#define AD3552R_REG_ADDR_CHIP_GRADE 0x06
+#define AD3552R_MASK_GRADE GENMASK(7, 4)
+#define AD3552R_MASK_DEVICE_REVISION GENMASK(3, 0)
+#define AD3552R_REG_ADDR_SCRATCH_PAD 0x0A
+#define AD3552R_REG_ADDR_SPI_REVISION 0x0B
+#define AD3552R_REG_ADDR_VENDOR_L 0x0C
+#define AD3552R_REG_ADDR_VENDOR_H 0x0D
+#define AD3552R_REG_ADDR_STREAM_MODE 0x0E
+#define AD3552R_MASK_LENGTH GENMASK(7, 0)
+#define AD3552R_REG_ADDR_TRANSFER_REGISTER 0x0F
+#define AD3552R_MASK_MULTI_IO_MODE GENMASK(7, 6)
+#define AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE BIT(2)
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_C 0x10
+#define AD3552R_MASK_CRC_ENABLE (GENMASK(7, 6) |\
+ GENMASK(1, 0))
+#define AD3552R_MASK_STRICT_REGISTER_ACCESS BIT(5)
+#define AD3552R_REG_ADDR_INTERFACE_STATUS_A 0x11
+#define AD3552R_MASK_INTERFACE_NOT_READY BIT(7)
+#define AD3552R_MASK_CLOCK_COUNTING_ERROR BIT(5)
+#define AD3552R_MASK_INVALID_OR_NO_CRC BIT(3)
+#define AD3552R_MASK_WRITE_TO_READ_ONLY_REGISTER BIT(2)
+#define AD3552R_MASK_PARTIAL_REGISTER_ACCESS BIT(1)
+#define AD3552R_MASK_REGISTER_ADDRESS_INVALID BIT(0)
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_D 0x14
+#define AD3552R_MASK_ALERT_ENABLE_PULLUP BIT(6)
+#define AD3552R_MASK_MEM_CRC_EN BIT(4)
+#define AD3552R_MASK_SDO_DRIVE_STRENGTH GENMASK(3, 2)
+#define AD3552R_MASK_DUAL_SPI_SYNCHROUNOUS_EN BIT(1)
+#define AD3552R_MASK_SPI_CONFIG_DDR BIT(0)
+#define AD3552R_REG_ADDR_SH_REFERENCE_CONFIG 0x15
+#define AD3552R_MASK_IDUMP_FAST_MODE BIT(6)
+#define AD3552R_MASK_SAMPLE_HOLD_DIFFERENTIAL_USER_EN BIT(5)
+#define AD3552R_MASK_SAMPLE_HOLD_USER_TRIM GENMASK(4, 3)
+#define AD3552R_MASK_SAMPLE_HOLD_USER_ENABLE BIT(2)
+#define AD3552R_MASK_REFERENCE_VOLTAGE_SEL GENMASK(1, 0)
+#define AD3552R_REG_ADDR_ERR_ALARM_MASK 0x16
+#define AD3552R_MASK_REF_RANGE_ALARM BIT(6)
+#define AD3552R_MASK_CLOCK_COUNT_ERR_ALARM BIT(5)
+#define AD3552R_MASK_MEM_CRC_ERR_ALARM BIT(4)
+#define AD3552R_MASK_SPI_CRC_ERR_ALARM BIT(3)
+#define AD3552R_MASK_WRITE_TO_READ_ONLY_ALARM BIT(2)
+#define AD3552R_MASK_PARTIAL_REGISTER_ACCESS_ALARM BIT(1)
+#define AD3552R_MASK_REGISTER_ADDRESS_INVALID_ALARM BIT(0)
+#define AD3552R_REG_ADDR_ERR_STATUS 0x17
+#define AD3552R_MASK_REF_RANGE_ERR_STATUS BIT(6)
+#define AD3552R_MASK_DUAL_SPI_STREAM_EXCEEDS_DAC_ERR_STATUS BIT(5)
+#define AD3552R_MASK_MEM_CRC_ERR_STATUS BIT(4)
+#define AD3552R_MASK_RESET_STATUS BIT(0)
+#define AD3552R_REG_ADDR_POWERDOWN_CONFIG 0x18
+#define AD3552R_MASK_CH_DAC_POWERDOWN(ch) BIT(4 + (ch))
+#define AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(ch) BIT(ch)
+#define AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE 0x19
+#define AD3552R_MASK_CH_OUTPUT_RANGE_SEL(ch) ((ch) ? GENMASK(7, 4) :\
+ GENMASK(3, 0))
+#define AD3552R_REG_ADDR_CH_OFFSET(ch) (0x1B + (ch) * 2)
+#define AD3552R_MASK_CH_OFFSET_BITS_0_7 GENMASK(7, 0)
+#define AD3552R_REG_ADDR_CH_GAIN(ch) (0x1C + (ch) * 2)
+#define AD3552R_MASK_CH_RANGE_OVERRIDE BIT(7)
+#define AD3552R_MASK_CH_GAIN_SCALING_N GENMASK(6, 5)
+#define AD3552R_MASK_CH_GAIN_SCALING_P GENMASK(4, 3)
+#define AD3552R_MASK_CH_OFFSET_POLARITY BIT(2)
+#define AD3552R_MASK_CH_OFFSET_BIT_8 BIT(0)
+/*
+ * Secondary region
+ * For multibyte registers specify the highest address because the access is
+ * done in descending order
+ */
+#define AD3552R_SECONDARY_REGION_START 0x28
+#define AD3552R_REG_ADDR_HW_LDAC_16B 0x28
+#define AD3552R_REG_ADDR_CH_DAC_16B(ch) (0x2C - (1 - ch) * 2)
+#define AD3552R_REG_ADDR_DAC_PAGE_MASK_16B 0x2E
+#define AD3552R_REG_ADDR_CH_SELECT_16B 0x2F
+#define AD3552R_REG_ADDR_INPUT_PAGE_MASK_16B 0x31
+#define AD3552R_REG_ADDR_SW_LDAC_16B 0x32
+#define AD3552R_REG_ADDR_CH_INPUT_16B(ch) (0x36 - (1 - ch) * 2)
+/* 3 bytes registers */
+#define AD3552R_REG_START_24B 0x37
+#define AD3552R_REG_ADDR_HW_LDAC_24B 0x37
+#define AD3552R_REG_ADDR_CH_DAC_24B(ch) (0x3D - (1 - ch) * 3)
+#define AD3552R_REG_ADDR_DAC_PAGE_MASK_24B 0x40
+#define AD3552R_REG_ADDR_CH_SELECT_24B 0x41
+#define AD3552R_REG_ADDR_INPUT_PAGE_MASK_24B 0x44
+#define AD3552R_REG_ADDR_SW_LDAC_24B 0x45
+#define AD3552R_REG_ADDR_CH_INPUT_24B(ch) (0x4B - (1 - ch) * 3)
+
+/* Useful defines */
+#define AD3552R_NUM_CH 2
+#define AD3552R_MASK_CH(ch) BIT(ch)
+#define AD3552R_MASK_ALL_CH GENMASK(1, 0)
+#define AD3552R_MAX_REG_SIZE 3
+#define AD3552R_READ_BIT BIT(7)
+#define AD3552R_ADDR_MASK GENMASK(6, 0)
+#define AD3552R_MASK_DAC_12B 0xFFF0
+#define AD3552R_DEFAULT_CONFIG_B_VALUE 0x8
+#define AD3552R_SCRATCH_PAD_TEST_VAL1 0x34
+#define AD3552R_SCRATCH_PAD_TEST_VAL2 0xB2
+#define AD3552R_GAIN_SCALE 1000
+#define AD3552R_LDAC_PULSE_US 100
+
+enum ad3552r_ch_vref_select {
+ /* Internal source with Vref I/O floating */
+ AD3552R_INTERNAL_VREF_PIN_FLOATING,
+ /* Internal source with Vref I/O at 2.5V */
+ AD3552R_INTERNAL_VREF_PIN_2P5V,
+ /* External source with Vref I/O as input */
+ AD3552R_EXTERNAL_VREF_PIN_INPUT
+};
+
+enum ad3542r_id {
+ AD3542R_ID = 0x4008,
+ AD3552R_ID = 0x4009,
+};
+
+enum ad3552r_ch_output_range {
+ /* Range from 0 V to 2.5 V. Requires Rfb1x connection */
+ AD3552R_CH_OUTPUT_RANGE_0__2P5V,
+ /* Range from 0 V to 5 V. Requires Rfb1x connection */
+ AD3552R_CH_OUTPUT_RANGE_0__5V,
+ /* Range from 0 V to 10 V. Requires Rfb2x connection */
+ AD3552R_CH_OUTPUT_RANGE_0__10V,
+ /* Range from -5 V to 5 V. Requires Rfb2x connection */
+ AD3552R_CH_OUTPUT_RANGE_NEG_5__5V,
+ /* Range from -10 V to 10 V. Requires Rfb4x connection */
+ AD3552R_CH_OUTPUT_RANGE_NEG_10__10V,
+};
+
+static const s32 ad3552r_ch_ranges[][2] = {
+ [AD3552R_CH_OUTPUT_RANGE_0__2P5V] = {0, 2500},
+ [AD3552R_CH_OUTPUT_RANGE_0__5V] = {0, 5000},
+ [AD3552R_CH_OUTPUT_RANGE_0__10V] = {0, 10000},
+ [AD3552R_CH_OUTPUT_RANGE_NEG_5__5V] = {-5000, 5000},
+ [AD3552R_CH_OUTPUT_RANGE_NEG_10__10V] = {-10000, 10000}
+};
+
+enum ad3542r_ch_output_range {
+ /* Range from 0 V to 2.5 V. Requires Rfb1x connection */
+ AD3542R_CH_OUTPUT_RANGE_0__2P5V,
+ /* Range from 0 V to 3 V. Requires Rfb1x connection */
+ AD3542R_CH_OUTPUT_RANGE_0__3V,
+ /* Range from 0 V to 5 V. Requires Rfb1x connection */
+ AD3542R_CH_OUTPUT_RANGE_0__5V,
+ /* Range from 0 V to 10 V. Requires Rfb2x connection */
+ AD3542R_CH_OUTPUT_RANGE_0__10V,
+ /* Range from -2.5 V to 7.5 V. Requires Rfb2x connection */
+ AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V,
+ /* Range from -5 V to 5 V. Requires Rfb2x connection */
+ AD3542R_CH_OUTPUT_RANGE_NEG_5__5V,
+};
+
+static const s32 ad3542r_ch_ranges[][2] = {
+ [AD3542R_CH_OUTPUT_RANGE_0__2P5V] = {0, 2500},
+ [AD3542R_CH_OUTPUT_RANGE_0__3V] = {0, 3000},
+ [AD3542R_CH_OUTPUT_RANGE_0__5V] = {0, 5000},
+ [AD3542R_CH_OUTPUT_RANGE_0__10V] = {0, 10000},
+ [AD3542R_CH_OUTPUT_RANGE_NEG_2P5__7P5V] = {-2500, 7500},
+ [AD3542R_CH_OUTPUT_RANGE_NEG_5__5V] = {-5000, 5000}
+};
+
+enum ad3552r_ch_gain_scaling {
+ /* Gain scaling of 1 */
+ AD3552R_CH_GAIN_SCALING_1,
+ /* Gain scaling of 0.5 */
+ AD3552R_CH_GAIN_SCALING_0_5,
+ /* Gain scaling of 0.25 */
+ AD3552R_CH_GAIN_SCALING_0_25,
+ /* Gain scaling of 0.125 */
+ AD3552R_CH_GAIN_SCALING_0_125,
+};
+
+/* Gain * AD3552R_GAIN_SCALE */
+static const s32 gains_scaling_table[] = {
+ [AD3552R_CH_GAIN_SCALING_1] = 1000,
+ [AD3552R_CH_GAIN_SCALING_0_5] = 500,
+ [AD3552R_CH_GAIN_SCALING_0_25] = 250,
+ [AD3552R_CH_GAIN_SCALING_0_125] = 125
+};
+
+enum ad3552r_dev_attributes {
+ /* - Direct register values */
+ /* From 0-3 */
+ AD3552R_SDO_DRIVE_STRENGTH,
+ /*
+ * 0 -> Internal Vref, vref_io pin floating (default)
+ * 1 -> Internal Vref, vref_io driven by internal vref
+ * 2 or 3 -> External Vref
+ */
+ AD3552R_VREF_SELECT,
+ /* Read registers in ascending order if set. Else descending */
+ AD3552R_ADDR_ASCENSION,
+};
+
+enum ad3552r_ch_attributes {
+ /* DAC powerdown */
+ AD3552R_CH_DAC_POWERDOWN,
+ /* DAC amplifier powerdown */
+ AD3552R_CH_AMPLIFIER_POWERDOWN,
+ /* Select the output range. Select from enum ad3552r_ch_output_range */
+ AD3552R_CH_OUTPUT_RANGE_SEL,
+ /*
+ * Over-rider the range selector in order to manually set the output
+ * voltage range
+ */
+ AD3552R_CH_RANGE_OVERRIDE,
+ /* Manually set the offset voltage */
+ AD3552R_CH_GAIN_OFFSET,
+ /* Sets the polarity of the offset. */
+ AD3552R_CH_GAIN_OFFSET_POLARITY,
+ /* PDAC gain scaling */
+ AD3552R_CH_GAIN_SCALING_P,
+ /* NDAC gain scaling */
+ AD3552R_CH_GAIN_SCALING_N,
+ /* Rfb value */
+ AD3552R_CH_RFB,
+ /* Channel select. When set allow Input -> DAC and Mask -> DAC */
+ AD3552R_CH_SELECT,
+};
+
+struct ad3552r_ch_data {
+ s32 scale_int;
+ s32 scale_dec;
+ s32 offset_int;
+ s32 offset_dec;
+ s16 gain_offset;
+ u16 rfb;
+ u8 n;
+ u8 p;
+ u8 range;
+ bool range_override;
+};
+
+struct ad3552r_desc {
+ /* Used to look the spi bus for atomic operations where needed */
+ struct mutex lock;
+ struct gpio_desc *gpio_reset;
+ struct gpio_desc *gpio_ldac;
+ struct spi_device *spi;
+ struct ad3552r_ch_data ch_data[AD3552R_NUM_CH];
+ struct iio_chan_spec channels[AD3552R_NUM_CH + 1];
+ unsigned long enabled_ch;
+ unsigned int num_ch;
+ enum ad3542r_id chip_id;
+};
+
+static const u16 addr_mask_map[][2] = {
+ [AD3552R_ADDR_ASCENSION] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_A,
+ AD3552R_MASK_ADDR_ASCENSION
+ },
+ [AD3552R_SDO_DRIVE_STRENGTH] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_SDO_DRIVE_STRENGTH
+ },
+ [AD3552R_VREF_SELECT] = {
+ AD3552R_REG_ADDR_SH_REFERENCE_CONFIG,
+ AD3552R_MASK_REFERENCE_VOLTAGE_SEL
+ },
+};
+
+/* 0 -> reg addr, 1->ch0 mask, 2->ch1 mask */
+static const u16 addr_mask_map_ch[][3] = {
+ [AD3552R_CH_DAC_POWERDOWN] = {
+ AD3552R_REG_ADDR_POWERDOWN_CONFIG,
+ AD3552R_MASK_CH_DAC_POWERDOWN(0),
+ AD3552R_MASK_CH_DAC_POWERDOWN(1)
+ },
+ [AD3552R_CH_AMPLIFIER_POWERDOWN] = {
+ AD3552R_REG_ADDR_POWERDOWN_CONFIG,
+ AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(0),
+ AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(1)
+ },
+ [AD3552R_CH_OUTPUT_RANGE_SEL] = {
+ AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE,
+ AD3552R_MASK_CH_OUTPUT_RANGE_SEL(0),
+ AD3552R_MASK_CH_OUTPUT_RANGE_SEL(1)
+ },
+ [AD3552R_CH_SELECT] = {
+ AD3552R_REG_ADDR_CH_SELECT_16B,
+ AD3552R_MASK_CH(0),
+ AD3552R_MASK_CH(1)
+ }
+};
+
+static u8 _ad3552r_reg_len(u8 addr)
+{
+ switch (addr) {
+ case AD3552R_REG_ADDR_HW_LDAC_16B:
+ case AD3552R_REG_ADDR_CH_SELECT_16B:
+ case AD3552R_REG_ADDR_SW_LDAC_16B:
+ case AD3552R_REG_ADDR_HW_LDAC_24B:
+ case AD3552R_REG_ADDR_CH_SELECT_24B:
+ case AD3552R_REG_ADDR_SW_LDAC_24B:
+ return 1;
+ default:
+ break;
+ }
+
+ if (addr > AD3552R_REG_ADDR_HW_LDAC_24B)
+ return 3;
+ if (addr > AD3552R_REG_ADDR_HW_LDAC_16B)
+ return 2;
+
+ return 1;
+}
+
+/* SPI transfer to device */
+static int ad3552r_transfer(struct ad3552r_desc *dac, u8 addr, u32 len,
+ u8 *data, bool is_read)
+{
+ /* Maximum transfer: Addr (1B) + 2 * (Data Reg (3B)) + SW LDAC(1B) */
+ u8 buf[8];
+
+ buf[0] = addr & AD3552R_ADDR_MASK;
+ buf[0] |= is_read ? AD3552R_READ_BIT : 0;
+ if (is_read)
+ return spi_write_then_read(dac->spi, buf, 1, data, len);
+
+ memcpy(buf + 1, data, len);
+ return spi_write_then_read(dac->spi, buf, len + 1, NULL, 0);
+}
+
+static int ad3552r_write_reg(struct ad3552r_desc *dac, u8 addr, u16 val)
+{
+ u8 reg_len;
+ u8 buf[AD3552R_MAX_REG_SIZE] = { 0 };
+
+ reg_len = _ad3552r_reg_len(addr);
+ if (reg_len == 2)
+ /* Only DAC register are 2 bytes wide */
+ val &= AD3552R_MASK_DAC_12B;
+ if (reg_len == 1)
+ buf[0] = val & 0xFF;
+ else
+ /* reg_len can be 2 or 3, but 3rd bytes needs to be set to 0 */
+ put_unaligned_be16(val, buf);
+
+ return ad3552r_transfer(dac, addr, reg_len, buf, false);
+}
+
+static int ad3552r_read_reg(struct ad3552r_desc *dac, u8 addr, u16 *val)
+{
+ int err;
+ u8 reg_len, buf[AD3552R_MAX_REG_SIZE] = { 0 };
+
+ reg_len = _ad3552r_reg_len(addr);
+ err = ad3552r_transfer(dac, addr, reg_len, buf, true);
+ if (err)
+ return err;
+
+ if (reg_len == 1)
+ *val = buf[0];
+ else
+ /* reg_len can be 2 or 3, but only first 2 bytes are relevant */
+ *val = get_unaligned_be16(buf);
+
+ return 0;
+}
+
+static u16 ad3552r_field_prep(u16 val, u16 mask)
+{
+ return (val << __ffs(mask)) & mask;
+}
+
+/* Update field of a register, shift val if needed */
+static int ad3552r_update_reg_field(struct ad3552r_desc *dac, u8 addr, u16 mask,
+ u16 val)
+{
+ int ret;
+ u16 reg;
+
+ ret = ad3552r_read_reg(dac, addr, ®);
+ if (ret < 0)
+ return ret;
+
+ reg &= ~mask;
+ reg |= ad3552r_field_prep(val, mask);
+
+ return ad3552r_write_reg(dac, addr, reg);
+}
+
+static int ad3552r_set_ch_value(struct ad3552r_desc *dac,
+ enum ad3552r_ch_attributes attr,
+ u8 ch,
+ u16 val)
+{
+ /* Update register related to attributes in chip */
+ return ad3552r_update_reg_field(dac, addr_mask_map_ch[attr][0],
+ addr_mask_map_ch[attr][ch + 1], val);
+}
+
+#define AD3552R_CH_DAC(_idx) ((struct iio_chan_spec) { \
+ .type = IIO_VOLTAGE, \
+ .output = true, \
+ .indexed = true, \
+ .channel = _idx, \
+ .scan_index = _idx, \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_BE, \
+ }, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_ENABLE) | \
+ BIT(IIO_CHAN_INFO_OFFSET), \
+})
+
+static int ad3552r_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val,
+ int *val2,
+ long mask)
+{
+ struct ad3552r_desc *dac = iio_priv(indio_dev);
+ u16 tmp_val;
+ int err;
+ u8 ch = chan->channel;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&dac->lock);
+ err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_CH_DAC_24B(ch),
+ &tmp_val);
+ mutex_unlock(&dac->lock);
+ if (err < 0)
+ return err;
+ *val = tmp_val;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_ENABLE:
+ mutex_lock(&dac->lock);
+ err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_POWERDOWN_CONFIG,
+ &tmp_val);
+ mutex_unlock(&dac->lock);
+ if (err < 0)
+ return err;
+ *val = !((tmp_val & AD3552R_MASK_CH_DAC_POWERDOWN(ch)) >>
+ __ffs(AD3552R_MASK_CH_DAC_POWERDOWN(ch)));
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = dac->ch_data[ch].scale_int;
+ *val2 = dac->ch_data[ch].scale_dec;
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_OFFSET:
+ *val = dac->ch_data[ch].offset_int;
+ *val2 = dac->ch_data[ch].offset_dec;
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad3552r_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ struct ad3552r_desc *dac = iio_priv(indio_dev);
+ int err;
+
+ mutex_lock(&dac->lock);
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ err = ad3552r_write_reg(dac,
+ AD3552R_REG_ADDR_CH_DAC_24B(chan->channel),
+ val);
+ break;
+ case IIO_CHAN_INFO_ENABLE:
+ err = ad3552r_set_ch_value(dac, AD3552R_CH_DAC_POWERDOWN,
+ chan->channel, !val);
+ break;
+ default:
+ err = -EINVAL;
+ break;
+ }
+ mutex_unlock(&dac->lock);
+
+ return err;
+}
+
+static const struct iio_info ad3552r_iio_info = {
+ .read_raw = ad3552r_read_raw,
+ .write_raw = ad3552r_write_raw
+};
+
+static int32_t ad3552r_trigger_hw_ldac(struct gpio_desc *ldac)
+{
+ gpiod_set_value_cansleep(ldac, 0);
+ usleep_range(AD3552R_LDAC_PULSE_US, AD3552R_LDAC_PULSE_US + 10);
+ gpiod_set_value_cansleep(ldac, 1);
+
+ return 0;
+}
+
+static int ad3552r_write_all_channels(struct ad3552r_desc *dac, u8 *data)
+{
+ int err, len;
+ u8 addr, buff[AD3552R_NUM_CH * AD3552R_MAX_REG_SIZE + 1];
+
+ addr = AD3552R_REG_ADDR_CH_INPUT_24B(1);
+ /* CH1 */
+ memcpy(buff, data + 2, 2);
+ buff[2] = 0;
+ /* CH0 */
+ memcpy(buff + 3, data, 2);
+ buff[5] = 0;
+ len = 6;
+ if (!dac->gpio_ldac) {
+ /* Software LDAC */
+ buff[6] = AD3552R_MASK_ALL_CH;
+ ++len;
+ }
+ err = ad3552r_transfer(dac, addr, len, buff, false);
+ if (err)
+ return err;
+
+ if (dac->gpio_ldac)
+ return ad3552r_trigger_hw_ldac(dac->gpio_ldac);
+
+ return 0;
+}
+
+static int ad3552r_write_codes(struct ad3552r_desc *dac, u32 mask, u8 *data)
+{
+ int err;
+ u8 addr, buff[AD3552R_MAX_REG_SIZE];
+
+ if (mask == AD3552R_MASK_ALL_CH) {
+ if (memcmp(data, data + 2, 2) != 0)
+ return ad3552r_write_all_channels(dac, data);
+
+ addr = AD3552R_REG_ADDR_INPUT_PAGE_MASK_24B;
+ } else {
+ addr = AD3552R_REG_ADDR_CH_INPUT_24B(__ffs(mask));
+ }
+
+ memcpy(buff, data, 2);
+ buff[2] = 0;
+ err = ad3552r_transfer(dac, addr, 3, data, false);
+ if (err)
+ return err;
+
+ if (dac->gpio_ldac)
+ return ad3552r_trigger_hw_ldac(dac->gpio_ldac);
+
+ return ad3552r_write_reg(dac, AD3552R_REG_ADDR_SW_LDAC_24B, mask);
+}
+
+static irqreturn_t ad3552r_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct iio_buffer *buf = indio_dev->buffer;
+ struct ad3552r_desc *dac = iio_priv(indio_dev);
+ /* Maximum size of a scan */
+ u8 buff[AD3552R_NUM_CH * AD3552R_MAX_REG_SIZE];
+ int err;
+
+ memset(buff, 0, sizeof(buff));
+ err = iio_pop_from_buffer(buf, buff);
+ if (err)
+ goto end;
+
+ mutex_lock(&dac->lock);
+ ad3552r_write_codes(dac, *indio_dev->active_scan_mask, buff);
+ mutex_unlock(&dac->lock);
+end:
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static int ad3552r_check_scratch_pad(struct ad3552r_desc *dac)
+{
+ const u16 val1 = AD3552R_SCRATCH_PAD_TEST_VAL1;
+ const u16 val2 = AD3552R_SCRATCH_PAD_TEST_VAL2;
+ u16 val;
+ int err;
+
+ err = ad3552r_write_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, val1);
+ if (err < 0)
+ return err;
+
+ err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, &val);
+ if (err < 0)
+ return err;
+
+ if (val1 != val)
+ return -ENODEV;
+
+ err = ad3552r_write_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, val2);
+ if (err < 0)
+ return err;
+
+ err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_SCRATCH_PAD, &val);
+ if (err < 0)
+ return err;
+
+ if (val2 != val)
+ return -ENODEV;
+
+ return 0;
+}
+
+struct reg_addr_pool {
+ struct ad3552r_desc *dac;
+ u8 addr;
+};
+
+static int ad3552r_read_reg_wrapper(struct reg_addr_pool *addr)
+{
+ int err;
+ u16 val;
+
+ err = ad3552r_read_reg(addr->dac, addr->addr, &val);
+ if (err)
+ return err;
+
+ return val;
+}
+
+static int ad3552r_reset(struct ad3552r_desc *dac)
+{
+ struct reg_addr_pool addr;
+ int ret;
+ u16 val;
+
+ dac->gpio_reset = devm_gpiod_get_optional(&dac->spi->dev, "reset",
+ GPIOD_OUT_LOW);
+ if (IS_ERR(dac->gpio_reset))
+ return dev_err_probe(&dac->spi->dev, PTR_ERR(dac->gpio_reset),
+ "Error while getting gpio reset");
+
+ if (dac->gpio_reset) {
+ /* Perform hardware reset */
+ usleep_range(10, 20);
+ gpiod_set_value_cansleep(dac->gpio_reset, 1);
+ } else {
+ /* Perform software reset if no GPIO provided */
+ ret = ad3552r_update_reg_field(dac,
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_A,
+ AD3552R_MASK_SOFTWARE_RESET,
+ AD3552R_MASK_SOFTWARE_RESET);
+ if (ret < 0)
+ return ret;
+
+ }
+
+ addr.dac = dac;
+ addr.addr = AD3552R_REG_ADDR_INTERFACE_CONFIG_B;
+ ret = readx_poll_timeout(ad3552r_read_reg_wrapper, &addr, val,
+ val == AD3552R_DEFAULT_CONFIG_B_VALUE ||
+ val < 0,
+ 5000, 50000);
+ if (val < 0)
+ ret = val;
+ if (ret) {
+ dev_err(&dac->spi->dev, "Error while resetting");
+ return ret;
+ }
+
+ ret = readx_poll_timeout(ad3552r_read_reg_wrapper, &addr, val,
+ !(val & AD3552R_MASK_INTERFACE_NOT_READY) ||
+ val < 0,
+ 5000, 50000);
+ if (val < 0)
+ ret = val;
+ if (ret) {
+ dev_err(&dac->spi->dev, "Error while resetting");
+ return ret;
+ }
+
+ return ad3552r_update_reg_field(dac,
+ addr_mask_map[AD3552R_ADDR_ASCENSION][0],
+ addr_mask_map[AD3552R_ADDR_ASCENSION][1],
+ val);
+}
+
+static void ad3552r_get_custom_range(struct ad3552r_desc *dac, s32 i, s32 *v_min,
+ s32 *v_max)
+{
+ s64 vref, tmp, common, offset, gn, gp;
+ /*
+ * From datasheet formula (In Volts):
+ * Vmin = 2.5 + [(GainN + Offset / 1024) * 2.5 * Rfb * 1.03]
+ * Vmax = 2.5 - [(GainP + Offset / 1024) * 2.5 * Rfb * 1.03]
+ * Calculus are converted to milivolts
+ */
+ vref = 2500;
+ /* 2.5 * 1.03 * 1000 (To mV) */
+ common = 2575 * dac->ch_data[i].rfb;
+ offset = dac->ch_data[i].gain_offset;
+
+ gn = gains_scaling_table[dac->ch_data[i].n];
+ tmp = (1024 * gn + AD3552R_GAIN_SCALE * offset) * common;
+ tmp = div_s64(tmp, 1024 * AD3552R_GAIN_SCALE);
+ *v_max = vref + tmp;
+
+ gp = gains_scaling_table[dac->ch_data[i].p];
+ tmp = (1024 * gp - AD3552R_GAIN_SCALE * offset) * common;
+ tmp = div_s64(tmp, 1024 * AD3552R_GAIN_SCALE);
+ *v_min = vref - tmp;
+}
+
+static void ad3552r_calc_gain_and_offset(struct ad3552r_desc *dac, s32 ch)
+{
+ s32 idx, v_max, v_min, span, rem;
+ s64 tmp;
+
+ if (dac->ch_data[ch].range_override) {
+ ad3552r_get_custom_range(dac, ch, &v_min, &v_max);
+ } else {
+ /* Normal range */
+ idx = dac->ch_data[ch].range;
+ if (dac->chip_id == AD3542R_ID) {
+ v_min = ad3542r_ch_ranges[idx][0];
+ v_max = ad3542r_ch_ranges[idx][1];
+ } else {
+ v_min = ad3552r_ch_ranges[idx][0];
+ v_max = ad3552r_ch_ranges[idx][1];
+ }
+ }
+
+ /*
+ * From datasheet formula:
+ * Vout = Span * (D / 65536) + Vmin
+ * Converted to scale and offset:
+ * Scale = Span / 65536
+ * Offset = 65536 * Vmin / Span
+ *
+ * Reminders are in micros in order to be printed as
+ * IIO_VAL_INT_PLUS_MICRO
+ */
+ span = v_max - v_min;
+ dac->ch_data[ch].scale_int = div_s64_rem(span, 65536, &rem);
+ /* Do operations in microvolts */
+ dac->ch_data[ch].scale_dec = DIV_ROUND_CLOSEST((s64)rem * 1000000,
+ 65536);
+
+ dac->ch_data[ch].offset_int = div_s64_rem(v_min * 65536, span, &rem);
+ tmp = (s64)rem * 1000000;
+ dac->ch_data[ch].offset_dec = div_s64(tmp, span);
+}
+
+static int ad3552r_find_range(u16 id, s32 *vals)
+{
+ int i, len;
+ const s32 (*ranges)[2];
+
+ if (id == AD3542R_ID) {
+ len = ARRAY_SIZE(ad3542r_ch_ranges);
+ ranges = ad3542r_ch_ranges;
+ } else {
+ len = ARRAY_SIZE(ad3552r_ch_ranges);
+ ranges = ad3552r_ch_ranges;
+ }
+
+ for (i = 0; i < len; i++)
+ if (vals[0] == ranges[i][0] * 1000 &&
+ vals[1] == ranges[i][1] * 1000)
+ return i;
+
+ return -EINVAL;
+}
+
+static int ad3552r_configure_custom_gain(struct ad3552r_desc *dac,
+ struct fwnode_handle *child,
+ u32 ch)
+{
+ struct device *dev = &dac->spi->dev;
+ struct fwnode_handle *gain_child;
+ u32 val;
+ int err;
+ u8 addr;
+ u16 reg = 0, offset;
+
+ gain_child = fwnode_get_named_child_node(child,
+ "custom-output-range-config");
+ if (IS_ERR(gain_child)) {
+ dev_err(dev,
+ "mandatory custom-output-range-config property missing\n");
+ return PTR_ERR(gain_child);
+ }
+
+ dac->ch_data[ch].range_override = 1;
+ reg |= ad3552r_field_prep(1, AD3552R_MASK_CH_RANGE_OVERRIDE);
+
+ err = fwnode_property_read_u32(gain_child, "adi,gain-scaling-p", &val);
+ if (err) {
+ dev_err(dev, "mandatory adi,gain-scaling-p property missing\n");
+ goto put_child;
+ }
+ reg |= ad3552r_field_prep(val, AD3552R_MASK_CH_GAIN_SCALING_P);
+ dac->ch_data[ch].p = val;
+
+ err = fwnode_property_read_u32(gain_child, "adi,gain-scaling-n", &val);
+ if (err) {
+ dev_err(dev, "mandatory adi,gain-scaling-n property missing\n");
+ goto put_child;
+ }
+ reg |= ad3552r_field_prep(val, AD3552R_MASK_CH_GAIN_SCALING_N);
+ dac->ch_data[ch].n = val;
+
+ err = fwnode_property_read_u32(gain_child, "adi,rfb-ohms", &val);
+ if (err) {
+ dev_err(dev, "mandatory adi,rfb-ohms property missing\n");
+ goto put_child;
+ }
+ dac->ch_data[ch].rfb = val;
+
+ err = fwnode_property_read_u32(gain_child, "adi,gain-offset", &val);
+ if (err) {
+ dev_err(dev, "mandatory adi,gain-offset property missing\n");
+ goto put_child;
+ }
+ dac->ch_data[ch].gain_offset = val;
+
+ offset = abs((s32)val);
+ reg |= ad3552r_field_prep((offset >> 8), AD3552R_MASK_CH_OFFSET_BIT_8);
+
+ reg |= ad3552r_field_prep((s32)val < 0, AD3552R_MASK_CH_OFFSET_POLARITY);
+ addr = AD3552R_REG_ADDR_CH_GAIN(ch);
+ err = ad3552r_write_reg(dac, addr,
+ offset & AD3552R_MASK_CH_OFFSET_BITS_0_7);
+ if (err) {
+ dev_err(dev, "Error writing register\n");
+ goto put_child;
+ }
+
+ err = ad3552r_write_reg(dac, addr, reg);
+ if (err) {
+ dev_err(dev, "Error writing register\n");
+ goto put_child;
+ }
+
+put_child:
+ fwnode_handle_put(gain_child);
+
+ return err;
+}
+
+static void ad3552r_reg_disable(void *reg)
+{
+ regulator_disable(reg);
+}
+
+static int ad3552r_configure_device(struct ad3552r_desc *dac)
+{
+ struct device *dev = &dac->spi->dev;
+ struct fwnode_handle *child;
+ struct regulator *vref;
+ int err, cnt = 0, voltage, delta = 100000;
+ u32 vals[2], val, ch;
+
+ dac->gpio_ldac = devm_gpiod_get_optional(dev, "ldac", GPIOD_OUT_HIGH);
+ if (IS_ERR(dac->gpio_ldac))
+ return dev_err_probe(dev, PTR_ERR(dac->gpio_ldac),
+ "Error getting gpio ldac");
+
+ vref = devm_regulator_get_optional(dev, "vref");
+ if (IS_ERR(vref)) {
+ if (PTR_ERR(vref) != -ENODEV)
+ return dev_err_probe(dev, PTR_ERR(vref),
+ "Error getting vref");
+
+ if (device_property_read_bool(dev, "adi,vref-out-en"))
+ val = AD3552R_INTERNAL_VREF_PIN_2P5V;
+ else
+ val = AD3552R_INTERNAL_VREF_PIN_FLOATING;
+ } else {
+ err = regulator_enable(vref);
+ if (err) {
+ dev_err(dev, "Failed to enable external vref supply\n");
+ return err;
+ }
+
+ err = devm_add_action_or_reset(dev, ad3552r_reg_disable, vref);
+ if (err) {
+ regulator_disable(vref);
+ return err;
+ }
+
+ voltage = regulator_get_voltage(vref);
+ if (voltage > 2500000 + delta || voltage < 2500000 - delta) {
+ dev_warn(dev, "vref-supply must be 2.5V");
+ return -EINVAL;
+ }
+ val = AD3552R_EXTERNAL_VREF_PIN_INPUT;
+ }
+
+ err = ad3552r_update_reg_field(dac,
+ addr_mask_map[AD3552R_VREF_SELECT][0],
+ addr_mask_map[AD3552R_VREF_SELECT][1],
+ val);
+ if (err)
+ return err;
+
+ err = device_property_read_u32(dev, "adi,sdo-drive-strength", &val);
+ if (!err) {
+ if (val > 3) {
+ dev_err(dev, "adi,sdo-drive-strength must be less than 4\n");
+ return -EINVAL;
+ }
+
+ err = ad3552r_update_reg_field(dac,
+ addr_mask_map[AD3552R_SDO_DRIVE_STRENGTH][0],
+ addr_mask_map[AD3552R_SDO_DRIVE_STRENGTH][1],
+ val);
+ if (err)
+ return err;
+ }
+
+ dac->num_ch = device_get_child_node_count(dev);
+ if (!dac->num_ch) {
+ dev_err(dev, "No channels defined\n");
+ return -ENODEV;
+ }
+
+ device_for_each_child_node(dev, child) {
+ err = fwnode_property_read_u32(child, "reg", &ch);
+ if (err) {
+ dev_err(dev, "mandatory reg property missing\n");
+ goto put_child;
+ }
+ if (ch >= AD3552R_NUM_CH) {
+ dev_err(dev, "reg must be less than %d\n",
+ AD3552R_NUM_CH);
+ err = -EINVAL;
+ goto put_child;
+ }
+
+ if (fwnode_property_present(child, "adi,output-range-microvolt")) {
+ err = fwnode_property_read_u32_array(child,
+ "adi,output-range-microvolt",
+ vals,
+ 2);
+ if (err) {
+ dev_err(dev,
+ "adi,output-range-microvolt property could not be parsed\n");
+ goto put_child;
+ }
+
+ err = ad3552r_find_range(dac->chip_id, vals);
+ if (err < 0) {
+ dev_err(dev,
+ "Invalid adi,output-range-microvolt value\n");
+ goto put_child;
+ }
+ val = err;
+ err = ad3552r_set_ch_value(dac,
+ AD3552R_CH_OUTPUT_RANGE_SEL,
+ ch, val);
+ if (err)
+ goto put_child;
+
+ dac->ch_data[ch].range = val;
+ } else if (dac->chip_id == AD3542R_ID) {
+ dev_err(dev,
+ "adi,output-range-microvolt is required for ad3542r\n");
+ err = -EINVAL;
+ goto put_child;
+ } else {
+ err = ad3552r_configure_custom_gain(dac, child, ch);
+ if (err)
+ goto put_child;
+ }
+
+ ad3552r_calc_gain_and_offset(dac, ch);
+ dac->enabled_ch |= BIT(ch);
+
+ err = ad3552r_set_ch_value(dac, AD3552R_CH_SELECT, ch, 1);
+ if (err < 0)
+ goto put_child;
+
+ dac->channels[cnt] = AD3552R_CH_DAC(ch);
+ ++cnt;
+
+ }
+
+ /* Disable unused channels */
+ for_each_clear_bit(ch, &dac->enabled_ch, AD3552R_NUM_CH) {
+ err = ad3552r_set_ch_value(dac, AD3552R_CH_AMPLIFIER_POWERDOWN,
+ ch, 1);
+ if (err)
+ return err;
+ }
+
+ dac->num_ch = cnt;
+
+ return 0;
+put_child:
+ fwnode_handle_put(child);
+
+ return err;
+}
+
+static int ad3552r_init(struct ad3552r_desc *dac)
+{
+ int err;
+ u16 val, id;
+
+ err = ad3552r_reset(dac);
+ if (err) {
+ dev_err(&dac->spi->dev, "Reset failed\n");
+ return err;
+ }
+
+ err = ad3552r_check_scratch_pad(dac);
+ if (err) {
+ dev_err(&dac->spi->dev, "Scratch pad test failed\n");
+ return err;
+ }
+
+ err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_PRODUCT_ID_L, &val);
+ if (err) {
+ dev_err(&dac->spi->dev, "Fail read PRODUCT_ID_L\n");
+ return err;
+ }
+
+ id = val;
+ err = ad3552r_read_reg(dac, AD3552R_REG_ADDR_PRODUCT_ID_H, &val);
+ if (err) {
+ dev_err(&dac->spi->dev, "Fail read PRODUCT_ID_H\n");
+ return err;
+ }
+
+ id |= val << 8;
+ if (id != dac->chip_id) {
+ dev_err(&dac->spi->dev, "Product id not matching\n");
+ return -ENODEV;
+ }
+
+ return ad3552r_configure_device(dac);
+}
+
+static int ad3552r_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ struct ad3552r_desc *dac;
+ struct iio_dev *indio_dev;
+ int err;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*dac));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ dac = iio_priv(indio_dev);
+ dac->spi = spi;
+ dac->chip_id = id->driver_data;
+
+ mutex_init(&dac->lock);
+
+ err = ad3552r_init(dac);
+ if (err)
+ return err;
+
+ /* Config triggered buffer device */
+ if (dac->chip_id == AD3552R_ID)
+ indio_dev->name = "ad3552r";
+ else
+ indio_dev->name = "ad3542r";
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->info = &ad3552r_iio_info;
+ indio_dev->num_channels = dac->num_ch;
+ indio_dev->channels = dac->channels;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ err = devm_iio_triggered_buffer_setup_ext(&indio_dev->dev, indio_dev, NULL,
+ &ad3552r_trigger_handler,
+ IIO_BUFFER_DIRECTION_OUT,
+ NULL,
+ NULL);
+ if (err)
+ return err;
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct spi_device_id ad3552r_id[] = {
+ { "ad3542r", AD3542R_ID },
+ { "ad3552r", AD3552R_ID },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, ad3552r_id);
+
+static const struct of_device_id ad3552r_of_match[] = {
+ { .compatible = "adi,ad3542r"},
+ { .compatible = "adi,ad3552r"},
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad3552r_of_match);
+
+static struct spi_driver ad3552r_driver = {
+ .driver = {
+ .name = "ad3552r",
+ .of_match_table = ad3552r_of_match,
+ },
+ .probe = ad3552r_probe,
+ .id_table = ad3552r_id
+};
+module_spi_driver(ad3552r_driver);
+
+MODULE_AUTHOR("Mihail Chindris <mihail.chindris@analog.com>");
+MODULE_DESCRIPTION("Analog Device AD3552R DAC");
+MODULE_LICENSE("GPL v2");
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