[PATCH v4 6/6] drivers:iio:dac: Add AD3552R driver support

From: Mihail Chindris
Date: Fri Aug 20 2021 - 13:01:34 EST

The AD3552R-16 is a low drift ultrafast, 16-bit accuracy,
current output digital-to-analog converter (DAC) designed
to generate multiple output voltage span ranges.
The AD3552R-16 operates with a fixed 2.5V reference.

analog.com/media/en/technical-documentation/data-sheets/ad3552r.pdf

Signed-off-by: Mihail Chindris <mihail.chindris@xxxxxxxxxx>
---
drivers/iio/dac/Kconfig | 10 +
drivers/iio/dac/Makefile | 1 +
drivers/iio/dac/ad3552r.c | 1419 +++++++++++++++++++++++++++++++++++++
3 files changed, 1430 insertions(+)
create mode 100644 drivers/iio/dac/ad3552r.c

diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index 75e1f2b48638..ced6428f2c92 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -6,6 +6,16 @@

menu "Digital to analog converters"

+config AD3552R
+ tristate "Analog Devices AD3552R DAC driver"
+ depends on SPI_MASTER
+ help
+ Say yes here to build support for Analog Devices AD3552R
+ Digital to Analog Converter.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad3552r.
+
config AD5064
tristate "Analog Devices AD5064 and similar multi-channel DAC driver"
depends on (SPI_MASTER && I2C!=m) || I2C
diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
index 33e16f14902a..dffe36efd8ff 100644
--- a/drivers/iio/dac/Makefile
+++ b/drivers/iio/dac/Makefile
@@ -4,6 +4,7 @@
#

# When adding new entries keep the list in alphabetical order
+obj-$(CONFIG_AD3552R) += ad3552r.o
obj-$(CONFIG_AD5360) += ad5360.o
obj-$(CONFIG_AD5380) += ad5380.o
obj-$(CONFIG_AD5421) += ad5421.o
diff --git a/drivers/iio/dac/ad3552r.c b/drivers/iio/dac/ad3552r.c
new file mode 100644
index 000000000000..89993dd87522
--- /dev/null
+++ b/drivers/iio/dac/ad3552r.c
@@ -0,0 +1,1419 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Analog Devices AD3552R
+ * Digital to Analog converter driver
+ *
+ * Copyright 2021 Analog Devices Inc.
+ */
+#include <linux/iopoll.h>
+#include <linux/device.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+#include <linux/time64.h>
+#include <linux/unaligned/be_byteshift.h>
+
+/* Register addresses */
+/* Primary address space */
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_A 0x00
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_B 0x01
+#define AD3552R_REG_ADDR_DEVICE_CONFIG 0x02
+#define AD3552R_REG_ADDR_CHIP_TYPE 0x03
+#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_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_REG_ADDR_TRANSFER_REGISTER 0x0F
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_C 0x10
+#define AD3552R_REG_ADDR_INTERFACE_STATUS_A 0x11
+#define AD3552R_REG_ADDR_INTERFACE_CONFIG_D 0x14
+#define AD3552R_REG_ADDR_SH_REFERENCE_CONFIG 0x15
+#define AD3552R_REG_ADDR_ERR_ALARM_MASK 0x16
+#define AD3552R_REG_ADDR_ERR_STATUS 0x17
+#define AD3552R_REG_ADDR_POWERDOWN_CONFIG 0x18
+#define AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE 0x19
+#define AD3552R_REG_ADDR_CH_OFFSET(ch) (0x1B + (ch) * 2)
+#define AD3552R_REG_ADDR_CH_GAIN(ch) (0x1C + (ch) * 2)
+/*
+ * 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)
+
+#define AD3552R_REG_ADDR_MAX 0x4B
+
+/* AD3552R_REG_ADDR_INTERFACE_CONFIG_A */
+#define AD3552R_MASK_SOFTWARE_RESET (BIT(7) | BIT(0))
+#define AD3552R_MASK_ADDR_ASCENSION BIT(5)
+#define AD3552R_MASK_SDO_ACTIVE BIT(4)
+/* AD3552R_REG_ADDR_INTERFACE_CONFIG_B */
+#define AD3552R_MASK_SINGLE_INST BIT(7)
+#define AD3552R_MASK_SHORT_INSTRUCTION BIT(3)
+/* AD3552R_REG_ADDR_DEVICE_CONFIG */
+#define AD3552R_MASK_DEVICE_STATUS(n) BIT(4 + (n))
+#define AD3552R_MASK_CUSTOM_MODES (BIT(3) | BIT(2))
+#define AD3552R_MASK_OPERATING_MODES (BIT(1) | BIT(0))
+/* AD3552R_REG_ADDR_CHIP_TYPE */
+#define AD3552R_MASK_CLASS 0x0F
+/* AD3552R_REG_ADDR_CHIP_GRADE */
+#define AD3552R_MASK_GRADE 0xF0
+#define AD3552R_MASK_DEVICE_REVISION 0x0F
+/* AD3552R_REG_ADDR_STREAM_MODE */
+#define AD3552R_MASK_LENGTH 0x0F
+/* AD3552R_REG_ADDR_TRANSFER_REGISTER */
+#define AD3552R_MASK_MULTI_IO_MODE (BIT(7) | BIT(6))
+#define AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE BIT(2)
+/* AD3552R_REG_ADDR_INTERFACE_CONFIG_C */
+#define AD3552R_MASK_CRC_ENABLE (BIT(7) | BIT(6) |\
+ BIT(1) | BIT(0))
+#define AD3552R_MASK_STRICT_REGISTER_ACCESS BIT(5)
+/* AD3552R_REG_ADDR_INTERFACE_STATUS_A */
+#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)
+/* AD3552R_REG_ADDR_INTERFACE_CONFIG_D */
+#define AD3552R_MASK_ALERT_ENABLE_PULLUP BIT(6)
+#define AD3552R_MASK_MEM_CRC_EN BIT(4)
+#define AD3552R_MASK_SDO_DRIVE_STRENGTH (BIT(3) | BIT(2))
+#define AD3552R_MASK_DUAL_SPI_SYNCHROUNOUS_EN BIT(1)
+#define AD3552R_MASK_SPI_CONFIG_DDR BIT(0)
+/* AD3552R_REG_ADDR_SH_REFERENCE_CONFIG */
+#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 (BIT(4) | BIT(3))
+#define AD3552R_MASK_SAMPLE_HOLD_USER_ENABLE BIT(2)
+#define AD3552R_MASK_REFERENCE_VOLTAGE_SEL (BIT(1) | BIT(0))
+/* AD3552R_REG_ADDR_ERR_ALARM_MASK */
+#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)
+/* AD3552R_REG_ADDR_ERR_STATUS */
+#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)
+/* AD3552R_REG_ADDR_POWERDOWN_CONFIG */
+#define AD3552R_MASK_CH_DAC_POWERDOWN(ch) BIT(4 + (ch))
+#define AD3552R_MASK_CH_AMPLIFIER_POWERDOWN(ch) BIT(ch)
+/* AD3552R_REG_ADDR_CH0_CH1_OUTPUT_RANGE */
+#define AD3552R_MASK_CH_OUTPUT_RANGE_SEL(ch) ((ch) ? 0xF0 : 0x0F)
+/* AD3552R_REG_ADDR_CH_GAIN */
+#define AD3552R_MASK_CH_RANGE_OVERRIDE BIT(7)
+#define AD3552R_MASK_CH_GAIN_SCALING_N (BIT(6) | BIT(5))
+#define AD3552R_MASK_CH_GAIN_SCALING_P (BIT(4) | BIT(3))
+#define AD3552R_MASK_CH_OFFSET_POLARITY BIT(2)
+#define AD3552R_MASK_CH_OFFSET_BIT_8 BIT(0)
+/* AD3552R_REG_ADDR_CH_OFFSET */
+#define AD3552R_MASK_CH_OFFSET_BITS_0_7 0xFF
+
+/* Useful defines */
+#define AD3552R_NUM_CH 2
+#define AD3552R_MASK_CH(ch) BIT(ch)
+#define AD3552R_PAGE_CH 2
+#define AD3552R_MAX_REG_SIZE 3
+#define AD3552R_READ_BIT (1 << 7)
+#define AD3552R_ADDR_MASK (~AD3552R_READ_BIT)
+#define AD3552R_CRC_ENABLE_VALUE (BIT(6) | BIT(1))
+#define AD3552R_CRC_DISABLE_VALUE (BIT(1) | BIT(0))
+#define AD3552R_CRC_POLY 0x07
+#define AD3552R_CRC_SEED 0xA5
+#define AD3552R_MASK_DAC_12B 0xFFF0
+#define AD3552R_DEFAULT_CONFIG_B_VALUE 0x8
+#define SCRATCH_PAD_TEST_VAL1 0x34
+#define SCRATCH_PAD_TEST_VAL2 0xB2
+#define TO_MICROS 1000000
+#define GAIN_SCALE 1000
+#define AD3552R_READ true
+#define AD3552R_WRITE false
+#define LDAC_PULSE_US 10
+
+enum ad3552r_ch_output_range {
+ /* Range from 0 V to 2.5 V. Requires Rfb1x connection */
+ AD3552R_CH_OUTPUT_RANGE_0__2_5V,
+ /* 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 -2.5 V to 7.5 V. Requires Rfb2x connection */
+ AD3552R_CH_OUTPUT_RANGE_NEG_5__5V,
+ /* Range from -6.5 V to 3.5 V. Requires Rfb4x connection */
+ AD3552R_CH_OUTPUT_RANGE_NEG_10__10V,
+};
+
+static const s32 ch_ranges[][2] = {
+ [AD3552R_CH_OUTPUT_RANGE_0__2_5V] = {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 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 * 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,
+ /* Enable / Disable CRC */
+ AD3552R_CRC_ENABLE,
+ /* Spi mode: Strandard, Dual or Quad */
+ AD3552R_SPI_MULTI_IO_MODE,
+ /* Spi data rate: Single or dual */
+ AD3552R_SPI_DATA_RATE,
+ /* Dual spi synchronous mode */
+ AD3552R_SPI_SYNCHRONOUS_ENABLE,
+
+ /* - Direct register values (Private) */
+ /* Read registers in ascending order if set. Else descending */
+ AD3552R_ADDR_ASCENSION,
+ /* Single instruction mode if set. Else, stream mode */
+ AD3552R_SINGLE_INST,
+ /* Number of addresses to loop on when stream writing. */
+ AD3552R_STREAM_MODE,
+ /* Keep stream value if set. */
+ AD3552R_STREAM_LENGTH_KEEP_VALUE,
+};
+
+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,
+ /* Trigger a software LDAC */
+ AD3552R_CH_TRIGGER_SOFTWARE_LDAC,
+ /* Hardware LDAC Mask */
+ AD3552R_CH_HW_LDAC_MASK,
+ /* Rfb value */
+ AD3552R_CH_RFB,
+ /* Channel select. When set allow Input -> DAC and Mask -> DAC */
+ AD3552R_CH_SELECT,
+ /* Raw value to be set to dac */
+ AD3552R_CH_CODE
+};
+
+struct ad3552r_ch_data {
+ u16 gain_offset : 9;
+ u16 range_override : 1;
+ u16 n : 2;
+ u16 p : 2;
+ u16 offset_polarity : 1;
+ u16 rfb;
+ u8 range;
+ s32 scale_int;
+ s32 scale_dec;
+ s32 offset_int;
+ s32 offset_dec;
+ bool prec_en;
+};
+
+struct ad3552r_desc {
+ struct iio_dev *indio_dev;
+ 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;
+ bool use_input_regs;
+ u8 buf_data[2 * (AD3552R_MAX_REG_SIZE + 2)] ____cacheline_aligned;
+};
+
+static const u16 addr_mask_map[][2] = {
+ [AD3552R_ADDR_ASCENSION] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_A,
+ AD3552R_MASK_ADDR_ASCENSION
+ },
+ [AD3552R_SINGLE_INST] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_B,
+ AD3552R_MASK_SINGLE_INST
+ },
+ [AD3552R_STREAM_MODE] = {
+ AD3552R_REG_ADDR_STREAM_MODE,
+ AD3552R_MASK_LENGTH
+ },
+ [AD3552R_STREAM_LENGTH_KEEP_VALUE] = {
+ AD3552R_REG_ADDR_TRANSFER_REGISTER,
+ AD3552R_MASK_STREAM_LENGTH_KEEP_VALUE
+ },
+ [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
+ },
+ [AD3552R_CRC_ENABLE] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_C,
+ AD3552R_MASK_CRC_ENABLE
+ },
+ [AD3552R_SPI_MULTI_IO_MODE] = {
+ AD3552R_REG_ADDR_TRANSFER_REGISTER,
+ AD3552R_MASK_MULTI_IO_MODE
+ },
+ [AD3552R_SPI_DATA_RATE] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_SPI_CONFIG_DDR
+ },
+ [AD3552R_SPI_SYNCHRONOUS_ENABLE] = {
+ AD3552R_REG_ADDR_INTERFACE_CONFIG_D,
+ AD3552R_MASK_DUAL_SPI_SYNCHROUNOUS_EN
+ },
+};
+
+/* 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)
+ },
+ /*
+ * This attributes are update by the chip on 16B and 24B no matter to
+ * what register the write is done
+ */
+ [AD3552R_CH_TRIGGER_SOFTWARE_LDAC] = {
+ AD3552R_REG_ADDR_SW_LDAC_16B,
+ AD3552R_MASK_CH(0),
+ AD3552R_MASK_CH(1)
+ },
+ [AD3552R_CH_HW_LDAC_MASK] = {
+ AD3552R_REG_ADDR_HW_LDAC_16B,
+ AD3552R_MASK_CH(0),
+ AD3552R_MASK_CH(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)
+{
+ if (addr > AD3552R_REG_ADDR_MAX)
+ return 0;
+
+ 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)
+{
+ int err;
+ u8 instr;
+
+ instr = addr & AD3552R_ADDR_MASK;
+ instr |= is_read ? AD3552R_READ_BIT : 0;
+ dac->buf_data[0] = instr;
+ if (is_read) {
+ err = spi_write_then_read(dac->spi, dac->buf_data, 1,
+ dac->buf_data + 1, len);
+ if (err)
+ return err;
+
+ memcpy(data, dac->buf_data + 1, len);
+
+ return 0;
+ }
+
+ memcpy(dac->buf_data + 1, data, len);
+ return spi_write(dac->spi, dac->buf_data, len + 1);
+}
+
+static int ad3552r_write_reg(struct ad3552r_desc *dac, u8 addr, u16 val)
+{
+ u8 reg_len, buf[AD3552R_MAX_REG_SIZE] = { 0 };
+
+ reg_len = _ad3552r_reg_len(addr);
+ if (!reg_len)
+ return -EINVAL;
+
+ 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 */
+ *((u16 *)buf) = cpu_to_be16(val);
+
+ return ad3552r_transfer(dac, addr, reg_len, buf,
+ AD3552R_WRITE);
+}
+
+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);
+ if (!reg_len)
+ return -EINVAL;
+
+ err = ad3552r_transfer(dac, addr, reg_len, buf, AD3552R_READ);
+ 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 = be16_to_cpu(*((u16 *)buf));
+
+ return 0;
+}
+
+/* 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, &reg);
+ if (ret < 0)
+ return ret;
+
+ reg = (reg & ~mask) | (val << __ffs(mask));
+
+ return ad3552r_write_reg(dac, addr, reg);
+}
+
+static int ad3552r_set_dev_value(struct ad3552r_desc *dac,
+ enum ad3552r_dev_attributes attr,
+ u16 val)
+{
+ switch (attr) {
+ case AD3552R_SPI_MULTI_IO_MODE:
+ case AD3552R_SPI_DATA_RATE:
+ case AD3552R_SPI_SYNCHRONOUS_ENABLE:
+ case AD3552R_CRC_ENABLE:
+ /* Not implemented */
+ return -EINVAL;
+ default:
+ return ad3552r_update_reg_field(dac, addr_mask_map[attr][0],
+ addr_mask_map[attr][1], val);
+ }
+
+ return 0;
+}
+
+static int ad3552r_set_offset_value(struct ad3552r_desc *dac, u8 ch, int val)
+{
+ int err;
+
+ err = ad3552r_write_reg(dac, AD3552R_REG_ADDR_CH_OFFSET(ch),
+ val & AD3552R_MASK_CH_OFFSET_BITS_0_7);
+ if (err)
+ return err;
+
+ err = ad3552r_update_reg_field(dac,
+ AD3552R_REG_ADDR_CH_GAIN(ch),
+ AD3552R_MASK_CH_OFFSET_BIT_8,
+ (val >> 8) & AD3552R_MASK_CH_OFFSET_BIT_8);
+ if (err)
+ return err;
+
+ dac->ch_data[ch].gain_offset = val;
+
+ return 0;
+}
+
+static int ad3552r_set_gain_value(struct ad3552r_desc *dac,
+ enum ad3552r_ch_attributes attr,
+ u8 ch,
+ int val)
+{
+ int reg_mask, err;
+
+ if (attr == AD3552R_CH_GAIN_OFFSET)
+ return ad3552r_set_offset_value(dac, ch, val);
+
+ switch (attr) {
+ case AD3552R_CH_RANGE_OVERRIDE:
+ val = !!val;
+ reg_mask = AD3552R_MASK_CH_RANGE_OVERRIDE;
+ break;
+ case AD3552R_CH_GAIN_OFFSET_POLARITY:
+ val = !!val;
+ reg_mask = AD3552R_MASK_CH_OFFSET_POLARITY;
+ break;
+ case AD3552R_CH_GAIN_SCALING_P:
+ reg_mask = AD3552R_MASK_CH_GAIN_SCALING_P;
+ break;
+ case AD3552R_CH_GAIN_SCALING_N:
+ reg_mask = AD3552R_MASK_CH_GAIN_SCALING_N;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ err = ad3552r_update_reg_field(dac, AD3552R_REG_ADDR_CH_GAIN(ch),
+ reg_mask, val);
+ if (err)
+ return err;
+
+ switch (attr) {
+ case AD3552R_CH_RANGE_OVERRIDE:
+ dac->ch_data[ch].range_override = val;
+ break;
+ case AD3552R_CH_GAIN_OFFSET_POLARITY:
+ dac->ch_data[ch].offset_polarity = val;
+ break;
+ case AD3552R_CH_GAIN_SCALING_P:
+ dac->ch_data[ch].p = val;
+ break;
+ case AD3552R_CH_GAIN_SCALING_N:
+ dac->ch_data[ch].n = val;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/* Iterate over mask and write required bytes */
+static int ad3552r_write_codes(struct ad3552r_desc *dac, u32 mask, u8 *vals)
+{
+ int err, i, reg_len, k = 0;
+ unsigned long lmask = mask;
+ u8 addr, buff[AD3552R_NUM_CH * AD3552R_MAX_REG_SIZE];
+ u16 val;
+
+ /* If writing to consecutive registers do just one transfer */
+
+ if (mask == (AD3552R_MASK_CH(0) | AD3552R_MASK_CH(1)) &&
+ dac->ch_data[0].prec_en == dac->ch_data[1].prec_en) {
+ if (dac->use_input_regs) {
+ if (dac->ch_data[0].prec_en)
+ addr = AD3552R_REG_ADDR_CH_INPUT_24B(1);
+ else
+ addr = AD3552R_REG_ADDR_CH_INPUT_16B(1);
+ } else {
+ if (dac->ch_data[0].prec_en)
+ addr = AD3552R_REG_ADDR_CH_DAC_24B(1);
+ else
+ addr = AD3552R_REG_ADDR_CH_DAC_16B(1);
+ }
+
+ reg_len = _ad3552r_reg_len(addr);
+ buff[0] = vals[0];
+ buff[reg_len] = vals[2];
+ if (dac->ch_data[0].prec_en) {
+ /* Reg_len is 3 here */
+ buff[1] = vals[1];
+ buff[2] = 0;
+ buff[4] = vals[3];
+ buff[5] = 0;
+ } else {
+ buff[1] = vals[1] & 0xf0;
+ buff[3] = vals[3] & 0xf0;
+ }
+
+ err = ad3552r_transfer(dac, addr, reg_len * 2, buff,
+ AD3552R_WRITE);
+ if (err)
+ return err;
+ } else {
+
+ k = 0;
+ for_each_set_bit(i, &lmask, AD3552R_NUM_CH + 1) {
+ /* Writing to mask CH */
+ if (i == AD3552R_PAGE_CH)
+ addr = dac->ch_data[0].prec_en ?
+ AD3552R_REG_ADDR_INPUT_PAGE_MASK_24B :
+ AD3552R_REG_ADDR_INPUT_PAGE_MASK_16B;
+ else
+ addr = dac->ch_data[i].prec_en ?
+ AD3552R_REG_ADDR_CH_INPUT_24B(i) :
+ AD3552R_REG_ADDR_CH_INPUT_16B(i);
+
+ reg_len = _ad3552r_reg_len(addr);
+ val = be16_to_cpu(*((u16 *)(vals + k)));
+
+ k += 2;
+ err = ad3552r_write_reg(dac, addr, val);
+ if (err)
+ return err;
+ }
+ }
+
+ if (dac->gpio_ldac) {
+ gpiod_set_value_cansleep(dac->gpio_ldac, 0);
+ usleep_range(LDAC_PULSE_US, LDAC_PULSE_US + 10);
+ gpiod_set_value_cansleep(dac->gpio_ldac, 1);
+ }
+
+ return 0;
+}
+
+static int ad3552r_get_ch_value(struct ad3552r_desc *dac,
+ enum ad3552r_ch_attributes attr,
+ u8 ch,
+ u16 *val)
+{
+ int ret;
+ u16 reg;
+ u8 addr;
+ u16 mask;
+
+ /* Attributes not defined in addr_mask_map_ch */
+ switch (attr) {
+ case AD3552R_CH_CODE:
+ return ad3552r_read_reg(dac, AD3552R_REG_ADDR_CH_DAC_24B(ch),
+ val);
+ case AD3552R_CH_RFB:
+ *val = dac->ch_data[ch].rfb;
+ return 0;
+ default:
+ break;
+ }
+
+ if (attr >= AD3552R_CH_RANGE_OVERRIDE &&
+ attr <= AD3552R_CH_GAIN_SCALING_N)
+ return -EINVAL;
+
+ addr = addr_mask_map_ch[attr][0];
+ if (addr == AD3552R_REG_ADDR_SW_LDAC_24B ||
+ addr == AD3552R_REG_ADDR_SW_LDAC_16B) {
+ dev_err(&dac->indio_dev->dev, "Write only registers\n");
+ /* LDAC are write only registers */
+ return -EINVAL;
+ }
+
+ ret = ad3552r_read_reg(dac, addr, &reg);
+ if (ret < 0)
+ return ret;
+
+ mask = addr_mask_map_ch[attr][ch + 1];
+ *val = (reg & mask) >> __ffs(mask);
+
+ return 0;
+}
+
+static int ad3552r_set_ch_value(struct ad3552r_desc *dac,
+ enum ad3552r_ch_attributes attr,
+ u8 ch,
+ u16 val)
+{
+ int ret;
+
+ /* Attributes not defined in addr_mask_map_ch */
+ switch (attr) {
+ case AD3552R_CH_CODE:
+ return ad3552r_write_reg(dac, AD3552R_REG_ADDR_CH_DAC_24B(ch),
+ val);
+ case AD3552R_CH_RFB:
+ dac->ch_data[ch].rfb = val;
+ return 0;
+ default:
+ break;
+ }
+
+ if (attr >= AD3552R_CH_RANGE_OVERRIDE &&
+ attr <= AD3552R_CH_GAIN_SCALING_N)
+ return ad3552r_set_gain_value(dac, attr, ch, val);
+
+ /* Update register related to attributes in chip */
+ ret = ad3552r_update_reg_field(dac, addr_mask_map_ch[attr][0],
+ addr_mask_map_ch[attr][ch + 1], val);
+ if (ret < 0)
+ return ret;
+
+ /* Update software structures */
+ if (attr == AD3552R_CH_OUTPUT_RANGE_SEL) {
+ val %= AD3552R_CH_OUTPUT_RANGE_NEG_10__10V + 1;
+ dac->ch_data[ch].range = val;
+ }
+
+ return ret;
+}
+
+static ssize_t ad3552r_write_ext(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ const char *buf, size_t len)
+{
+ struct ad3552r_desc *dac = iio_priv(indio_dev);
+ int val, frac, err;
+
+ err = iio_str_to_fixpoint(buf, 0, &val, &frac);
+ if (err < 0)
+ return err;
+
+ dac->ch_data[chan->channel].prec_en = !!val;
+
+ return len;
+}
+
+static ssize_t ad3552r_read_ext(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ char *buf)
+{
+ struct ad3552r_desc *dac = iio_priv(indio_dev);
+ int val;
+
+ if (private != 0)
+ return -EINVAL;
+
+ val = dac->ch_data[chan->channel].prec_en;
+
+ return iio_format_value(buf, IIO_VAL_INT, 1, &val);
+}
+
+#define AD3552R_CH_ATTR(_name, _what) { \
+ .name = _name, \
+ .read = ad3552r_read_ext, \
+ .write = ad3552r_write_ext, \
+ .private = _what, \
+ .shared = IIO_SEPARATE, \
+}
+
+static const struct iio_chan_spec_ext_info ad3552r_ext_info[] = {
+ AD3552R_CH_ATTR("precision_mode_en", 0),
+ {},
+};
+
+#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, \
+ }, \
+ .ext_info = ad3552r_ext_info, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_ENABLE) | \
+ BIT(IIO_CHAN_INFO_OFFSET), \
+})
+
+#define AD3552R_CH_DAC_PAGE(_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), \
+ .modified = 1, \
+ .channel2 = IIO_MOD_X_AND_Z, \
+})
+
+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);
+ if (chan->channel == AD3552R_PAGE_CH)
+ err = ad3552r_read_reg(dac,
+ AD3552R_REG_ADDR_DAC_PAGE_MASK_24B,
+ &tmp_val);
+ else
+ err = ad3552r_get_ch_value(dac, AD3552R_CH_CODE, ch,
+ &tmp_val);
+ if (err < 0) {
+ mutex_unlock(&dac->lock);
+ return err;
+ }
+
+ *val = tmp_val;
+ mutex_unlock(&dac->lock);
+ break;
+ case IIO_CHAN_INFO_ENABLE:
+ mutex_lock(&dac->lock);
+ err = ad3552r_get_ch_value(dac, AD3552R_CH_DAC_POWERDOWN,
+ ch, &tmp_val);
+ if (err < 0) {
+ mutex_unlock(&dac->lock);
+ return err;
+ }
+ *val = !tmp_val;
+ mutex_unlock(&dac->lock);
+ break;
+ 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;
+ }
+
+ return IIO_VAL_INT;
+}
+
+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);
+ enum ad3552r_ch_attributes attr;
+ int err = 0;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (chan->channel == AD3552R_PAGE_CH) {
+ mutex_lock(&dac->lock);
+ err = ad3552r_write_reg(dac,
+ AD3552R_REG_ADDR_DAC_PAGE_MASK_24B,
+ val);
+ mutex_unlock(&dac->lock);
+
+ return err;
+ }
+
+ attr = AD3552R_CH_CODE;
+ break;
+ case IIO_CHAN_INFO_ENABLE:
+ attr = AD3552R_CH_DAC_POWERDOWN;
+ val = !val;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ mutex_lock(&dac->lock);
+ err = ad3552r_set_ch_value(dac, attr, chan->channel, val);
+ mutex_unlock(&dac->lock);
+
+ return err;
+}
+
+static int ad3552r_update_scan_mode(struct iio_dev *indio_dev,
+ const unsigned long *scan_mask)
+{
+ u32 mask;
+
+ mask = *scan_mask;
+ /* If writing to mask, can't write to other channels */
+ if ((mask & AD3552R_MASK_CH(AD3552R_PAGE_CH)) &&
+ (mask & (~AD3552R_MASK_CH(AD3552R_PAGE_CH))))
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * Device type specific information.
+ */
+static const struct iio_info ad3552r_iio_info = {
+ .read_raw = ad3552r_read_raw,
+ .write_raw = ad3552r_write_raw,
+ .update_scan_mode = ad3552r_update_scan_mode
+};
+
+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);
+ char buff[AD3552R_NUM_CH * AD3552R_MAX_REG_SIZE];
+ int err;
+
+ memset(buff, 0, sizeof(buff));
+ mutex_lock(&dac->lock);
+ err = iio_buffer_remove_sample(buf, buff);
+ if (err)
+ goto end;
+
+ err = ad3552r_write_codes(dac, *indio_dev->active_scan_mask, buff);
+ if (err)
+ goto end;
+
+end:
+ iio_trigger_notify_done(indio_dev->trig);
+ mutex_unlock(&dac->lock);
+
+ return IRQ_HANDLED;
+}
+
+static int ad3552r_setup_trigger_buffer(struct device *dev,
+ struct iio_dev *indio_dev, int irq)
+{
+ struct ad3552r_desc *dac = iio_priv(indio_dev);
+ struct iio_trigger *hwtrig;
+ int err;
+
+ /* Configure trigger buffer */
+ err = devm_iio_triggered_buffer_setup_ext(dev, indio_dev, NULL,
+ &ad3552r_trigger_handler,
+ IIO_BUFFER_DIRECTION_OUT,
+ NULL,
+ NULL);
+ if (err)
+ return err;
+
+ if (!irq)
+ return 0;
+
+ hwtrig = devm_iio_trigger_alloc(dev, "%s-ldac-dev%d",
+ indio_dev->name,
+ iio_device_id(indio_dev));
+ if (!hwtrig)
+ return -ENOMEM;
+
+ hwtrig->dev.parent = dev;
+ iio_trigger_set_drvdata(hwtrig, dac);
+ err = devm_iio_trigger_register(dev, hwtrig);
+ if (err < 0)
+ return err;
+
+ return devm_request_threaded_irq(dev, irq,
+ iio_trigger_generic_data_rdy_poll,
+ NULL,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ indio_dev->name,
+ hwtrig);
+}
+
+static int ad3552r_check_scratch_pad(struct ad3552r_desc *dac)
+{
+ const u16 val1 = SCRATCH_PAD_TEST_VAL1;
+ const u16 val2 = 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 u16 ad3552r_read_reg_pool(struct reg_addr_pool *addr)
+{
+ u16 val = 0;
+
+ ad3552r_read_reg(addr->dac, addr->addr, &val);
+
+ 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 PTR_ERR(dac->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_pool,
+ &addr,
+ val,
+ (val == AD3552R_DEFAULT_CONFIG_B_VALUE),
+ 5000,
+ 50000);
+ if (ret) {
+ dev_err(&dac->spi->dev, "Err: %d\n", ret);
+ return ret;
+ }
+
+ ret = readx_poll_timeout(ad3552r_read_reg_pool,
+ &addr,
+ val,
+ (!(val & AD3552R_MASK_INTERFACE_NOT_READY)),
+ 5000,
+ 50000);
+ if (ret) {
+ dev_err(&dac->spi->dev, "Err: %d\n", ret);
+ return ret;
+ }
+
+ ret = ad3552r_set_dev_value(dac, AD3552R_ADDR_ASCENSION, 0);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+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;
+ if (dac->ch_data[i].offset_polarity)
+ offset *= -1;
+
+ gn = gains_scaling_table[dac->ch_data[i].n];
+ tmp = (1024 * gn + GAIN_SCALE * offset) * common;
+ tmp = div_s64(tmp, 1024 * GAIN_SCALE);
+ *v_max = vref + tmp;
+
+ gp = gains_scaling_table[dac->ch_data[i].p];
+ tmp = (1024 * gp - GAIN_SCALE * offset) * common;
+ tmp = div_s64(tmp, 1024 * GAIN_SCALE);
+ *v_min = vref - tmp;
+}
+
+static void ad3552r_set_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;
+ v_max = ch_ranges[idx][1];
+ v_min = ch_ranges[idx][0];
+ }
+
+ /*
+ * 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);
+ dac->ch_data[ch].scale_dec = DIV_ROUND_CLOSEST((s64)rem * TO_MICROS,
+ 65536);
+
+ dac->ch_data[ch].offset_int = div_s64_rem(v_min * 65536, span,
+ &rem);
+ tmp = (s64)rem * TO_MICROS;
+ dac->ch_data[ch].offset_dec = div_s64(tmp, span);
+}
+
+static const char * const gain_dts_names[] = {
+ "adi,gain-scaling-p",
+ "adi,gain-scaling-n",
+ "adi,rfb"
+};
+
+static int ad3552r_configure_device(struct ad3552r_desc *dac)
+{
+ static const enum ad3552r_ch_attributes gain_attrs[] = {
+ AD3552R_CH_GAIN_SCALING_P,
+ AD3552R_CH_GAIN_SCALING_N,
+ AD3552R_CH_RFB
+ };
+ struct fwnode_handle *child, *custom_gain_child = NULL;
+ int i, err, cnt = 0;
+ u32 val, ch;
+ bool is_custom;
+
+ dac->gpio_ldac = devm_gpiod_get_optional(&dac->spi->dev, "ldac",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(dac->gpio_ldac))
+ return PTR_ERR(dac->gpio_ldac);
+
+ dac->use_input_regs = device_property_read_bool(&dac->spi->dev,
+ "adi,synch_channels");
+
+ err = device_property_read_u32(&dac->spi->dev, "adi,vref-select", &val);
+ if (!err) {
+ if (val > 2) {
+ dev_err(&dac->spi->dev, "%s must be less than 3\n",
+ "adi,vref-select");
+ return -EINVAL;
+ }
+ err = ad3552r_set_dev_value(dac, AD3552R_VREF_SELECT, val);
+ if (err)
+ return err;
+ }
+
+ err = device_property_read_u32(&dac->spi->dev, "adi,sdo-drive-strength",
+ &val);
+ if (!err) {
+ if (val > 3) {
+ dev_err(&dac->spi->dev, "%s must be less than 4\n",
+ "adi,sdo-drive-strength");
+ return -EINVAL;
+ }
+ err = ad3552r_set_dev_value(dac, AD3552R_SDO_DRIVE_STRENGTH,
+ val);
+ if (err)
+ return err;
+ }
+
+ dac->num_ch = device_get_child_node_count(&dac->spi->dev);
+ if (!dac->num_ch) {
+ dev_err(&dac->spi->dev, "No channels defined\n");
+ return -ENODEV;
+ }
+
+ device_for_each_child_node(&dac->spi->dev, child) {
+ err = fwnode_property_read_u32(child, "reg", &ch);
+ if (err) {
+ dev_err(&dac->spi->dev, "Mandory reg property missing\n");
+ goto put_child;
+ }
+ if (ch >= AD3552R_NUM_CH) {
+ dev_err(&dac->spi->dev, "reg must be less than %d\n",
+ AD3552R_NUM_CH);
+ err = -EINVAL;
+ goto put_child;
+ }
+
+ if (fwnode_property_present(child, "adi,output-range")) {
+ is_custom = false;
+ err = fwnode_property_read_u32(child,
+ "adi,output-range",
+ &val);
+ if (err) {
+ dev_err(&dac->spi->dev,
+ "Mandory adi,output-range property missing\n");
+ goto put_child;
+ }
+
+ if (val > AD3552R_CH_OUTPUT_RANGE_NEG_10__10V) {
+ dev_err(&dac->spi->dev,
+ "adi,output-range must be less or equal than %d\n",
+ AD3552R_CH_OUTPUT_RANGE_NEG_10__10V + 1);
+ err = -EINVAL;
+ goto put_child;
+ }
+
+ err = ad3552r_set_ch_value(dac,
+ AD3552R_CH_OUTPUT_RANGE_SEL,
+ ch, val);
+ if (err)
+ goto put_child;
+ } else {
+ is_custom = true;
+ custom_gain_child =
+ fwnode_get_named_child_node(child,
+ "custom-output-range-config");
+ if (IS_ERR(custom_gain_child)) {
+ err = PTR_ERR(custom_gain_child);
+ dev_err(&dac->spi->dev,
+ "Mandory custom-output-range-config property missing\n");
+ goto put_child;
+ }
+
+ err = fwnode_property_read_u32(custom_gain_child,
+ "adi,gain-offset", &val);
+ if (err) {
+ dev_err(&dac->spi->dev,
+ "Mandory adi,gain-offset property missing\n");
+ goto put_child;
+ }
+
+ err = ad3552r_set_ch_value(dac,
+ AD3552R_CH_GAIN_OFFSET,
+ ch, abs((s32)val));
+ if (err)
+ goto put_child;
+
+ err = ad3552r_set_ch_value(dac, AD3552R_CH_GAIN_OFFSET_POLARITY,
+ ch, (s32)val < 0);
+ if (err)
+ goto put_child;
+
+ for (i = 0; i < ARRAY_SIZE(gain_attrs); ++i) {
+ err = fwnode_property_read_u32(custom_gain_child,
+ gain_dts_names[i],
+ &val);
+ if (err) {
+ dev_err(&dac->spi->dev,
+ "Mandory %s property missing\n",
+ gain_dts_names[i]);
+ goto put_child;
+ }
+
+ err = ad3552r_set_ch_value(dac, gain_attrs[i],
+ ch, val);
+ if (err)
+ goto put_child;
+ }
+ }
+
+ ad3552r_set_gain_and_offset(dac, ch);
+ err = ad3552r_set_ch_value(dac, AD3552R_CH_RANGE_OVERRIDE, ch,
+ is_custom);
+ if (err)
+ goto put_child;
+
+ dac->enabled_ch |= BIT(ch);
+
+ err = ad3552r_set_ch_value(dac, AD3552R_CH_SELECT, ch, 1);
+ if (err < 0)
+ return err;
+
+ dac->channels[cnt] = AD3552R_CH_DAC(ch);
+ ++cnt;
+
+ }
+
+ if (cnt == AD3552R_NUM_CH) {
+ dac->channels[cnt] = AD3552R_CH_DAC_PAGE(AD3552R_PAGE_CH);
+ ++cnt;
+ } else {
+ /* Disable unused channels */
+ for_each_clear_bit(ch, &dac->enabled_ch, AD3552R_PAGE_CH) {
+ err = ad3552r_set_ch_value(dac,
+ AD3552R_CH_AMPLIFIER_POWERDOWN,
+ ch,
+ 0);
+ if (err)
+ goto put_child;
+ }
+ }
+
+ dac->num_ch = cnt;
+
+put_child:
+ if (!IS_ERR_OR_NULL(custom_gain_child))
+ fwnode_handle_put(custom_gain_child);
+ fwnode_handle_put(child);
+
+ return err;
+}
+
+static int ad3552r_init(struct ad3552r_desc *dac)
+{
+ int err;
+
+ 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;
+ }
+
+ return ad3552r_configure_device(dac);
+}
+
+static int ad3552r_probe(struct spi_device *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->indio_dev = indio_dev;
+ dac->spi = spi;
+
+ mutex_init(&dac->lock);
+
+ err = ad3552r_init(dac);
+ if (err)
+ return err;
+
+ /* Config triggered buffer device */
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = "ad3552r";
+ 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 = ad3552r_setup_trigger_buffer(&spi->dev, indio_dev, spi->irq);
+ if (err)
+ return err;
+
+ return devm_iio_device_register(&spi->dev, indio_dev);
+}
+
+static const struct of_device_id ad3552r_of_match[] = {
+ { .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
+};
+module_spi_driver(ad3552r_driver);
+
+MODULE_AUTHOR("Mihail Chindris <mihail.chindris@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Device AD3552R DAC");
+MODULE_LICENSE("GPL v2");
--
2.27.0