[PATCH v4 0/2] iio: dac: Add support for AD5529R DAC

[PATCH v4 0/2] iio: dac: Add support for AD5529R DAC

[Janani Sunil]

This patch series adds support for Analog Devices AD5529R, a 16 channel
16 and 12 bit voltage Digital-to-Analog Converter (DAC) with integrated
precision reference. The AD5529R operates from both unipolar and
bipolar supplies. The device communicates via SPI interface.

**Device Overview:**
The AD5529R features 16 independent DAC channels, with 16 or 12 bit
resolution, allowing independently programmable output ranges. The
internal 4.096V precision reference sets the accuracy of the output
voltage.

**Features Implemented:**
- Support for AD5529R 12-bit and 16-bit variants via device match data.
- Reset support via GPIO.
- Dual regmap configuration to handle 8 and 16 bit registers.
- Per-channel output range configuration from devicetree.
- Optional external reference and bipolar supply handling.

**Patch Summary:**
1. **dt-bindings**: Binding documentation with channel configuration.
2. **driver**: Implement IIO DAC Driver with regmap support.

**Testing:**
The driver was compiled and tested on the EVAL-AD5529R-ARDZ using a
coraZ7 with a mainline v7.0 kernel.

**Driver Rationale:**
AD5529R introduces:
1. A unique register layout
2. Mixed 8-bit and 16-bit register accesses
3. Hardware specific features like function generators, multi-die
hotpath registers etc.

The device warrants its own drivers due to these fundamental
architectural differences, that would require substantial changes to
existing drivers without providing reusable benefits. The standalone
driver also allows future extensions for related devices in the same
family.

Signed-off-by: Janani Sunil <janani.sunil@analog.com>
---
Changes in v4:
- Fix DT child-node regex for hexadecimal channel addresses.
- Wrap long DT binding description lines.
- Simplify optional `vref-supply` and `hvss-supply` handling.
- Update REF_SEL programming for optional external reference use.
- Clean up range parsing and error messages.
- Simplify debugfs register access by calling regmap helpers directly.
- Add clarifying comments for reset settling time and RAW reads from `DAC_INPUT_A`.
- Remove an unused vref regulator pointer and an include.
- Rename the REF_SEL bit define and clean up small driver details.
- Toggle pins defined as PWM pins, instead of GPIOs
- Update cover letter to sync up latest changes.
- Link to v3: https://lore.kernel.org/r/20260519-ad5529r-driver-v3-0-267c0731aa68@analog.com

Changes in v3:
- Split into adi,ad5529r-16 and adi,ad5529r-12 device tree compatibles
- Add DT-based output range configuration via adi,output-range-microvolt
- Expand DT binding: vref-supply, clear/tg GPIOs, interrupts, muxout
- Correct power supply voltage specifications as per datasheet
- Reduce SPI frequency limit to 25MHz as per datasheet specs
- Switch to autoincrement addressing mode, remove +1 register offsets
- Use DT match data instead of device ID detection for fallback support
- Implement dynamic scale/offset calculation per configured channel range
- Added explicit val_format_endian and reg_stride for 16-bit regmap bus
- Code cleanup: alphabetical includes, ARRAY_SIZE(), unused defines
- Minor: .sign→.format field, simplify read/write order, optional hvss-supply
- Remove redundant driver documentation ad5529r.rst
- Link to v2: https://lore.kernel.org/r/20260508-ad5529r-driver-v2-0-e315441685d7@analog.com

Changes in v2:
- Fix IIO scale to use millivolts per ABI requirement
- Fix documentation voltage calculations (2.5V not 2.048V)
- Fix bipolar ranges in documentation (±5V, ±10V, ±15V, ±20V)
- Fix alphabetical ordering in documentation index
- Add missing newline to documentation file
- Fix scale units description (millivolts not microvolts)
- Include a section for driver rationale in the cover letter
- Reword contents in cover letter 12/16 bit generic->variant
- Add dependency array for spi-cpha and spi-cpol properties
- Link to v1: https://lore.kernel.org/r/20260507-ad5529r-driver-v1-0-b4460f3cb44f@analog.com

---
Janani Sunil (2):
      dt-bindings: iio: dac: Add AD5529R
      iio: dac: Add AD5529R DAC driver support

 .../devicetree/bindings/iio/dac/adi,ad5529r.yaml   | 208 +++++++++
 MAINTAINERS                                        |   8 +
 drivers/iio/dac/Kconfig                            |  17 +
 drivers/iio/dac/Makefile                           |   1 +
 drivers/iio/dac/ad5529r.c                          | 517 +++++++++++++++++++++
 5 files changed, 751 insertions(+)
---
base-commit: 93df88612859e8e19dec93c69d563b4b73e9bd4b
change-id: 20260507-ad5529r-driver-866bbdd864de

Best regards,
-- 
Janani Sunil <janani.sunil@analog.com>

[PATCH v4 1/2] dt-bindings: iio: dac: Add AD5529R

[Janani Sunil]

Devicetree bindings for AD5529R 16 channel 12/16 bit high voltage,
buffered voltage output digital-to-analog converter (DAC) with an
integrated precision reference.

Signed-off-by: Janani Sunil <janani.sunil@analog.com>
---
 .../devicetree/bindings/iio/dac/adi,ad5529r.yaml   | 208 +++++++++++++++++++++
 MAINTAINERS                                        |   7 +
 2 files changed, 215 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
new file mode 100644
index 000000000000..cc994f439be5
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
@@ -0,0 +1,208 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/dac/adi,ad5529r.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD5529R 16-Channel 12/16-bit High Voltage DAC
+
+maintainers:
+  - Janani Sunil <janani.sunil@analog.com>
+
+description: |
+  The AD5529R is a 16-channel, 12-bit or 16-bit, high voltage, buffered voltage
+  output digital-to-analog converter (DAC) with an integrated precision reference.
+  The device operates from unipolar and bipolar supplies. It is guaranteed
+  monotonic and has built-in rail-to-rail output buffers that can source or
+  sink up to 25mA.
+
+  Specifications:
+  * 16 independent 12-bit or 16-bit DAC channels
+  * Independently programmable output ranges: 0V to 5V, 0V to 10V, 0V to 20V,
+    0V to 40V, ±5V, ±10V, ±15V, and ±20V
+  * The device supports SPI communication with Mode 0 and Mode 3.
+  * 4.096V precision reference, 12ppm/°C maximum
+  * Built-in function generation: Toggle, Sinusoidal Dither, and Ramp waveforms
+  * Multiplexer for output voltage, load current sense and die temperature
+
+  Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad5529r.pdf
+
+properties:
+  compatible:
+    enum:
+      - adi,ad5529r-16   # 16-bit variant
+      - adi,ad5529r-12   # 12-bit variant
+
+  reg:
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 25000000
+    description:
+      Maximum SPI frequency. The device supports SPI Mode 0 and Mode 3.
+      Read operations are limited to 25MHz maximum.
+
+  reset-gpios:
+    maxItems: 1
+    description:
+      GPIO connected to the RESET pin. Active low. When asserted low,
+      performs a power-on reset and initializes the device to its default state.
+
+  clear-gpios:
+    maxItems: 1
+    description:
+      GPIO connected to the CLEAR pin. Active low. When asserted low,
+      clears all DAC data registers without affecting configuration settings.
+
+  interrupts:
+    maxItems: 1
+    description:
+      Interrupt connected to the ALARM pin. Active low interrupt output
+      for overtemperature conditions, SPI CRC errors, and function completion.
+
+  pwms:
+    minItems: 1
+    maxItems: 4
+    description:
+      PWM signals connected to the TG0-TG3 toggle pins. Pulsing these pins
+      based on trigger edge settings allows selected DACs to be updated
+      synchronously for digital function generation.
+
+  pwm-names:
+    minItems: 1
+    maxItems: 4
+    items:
+      enum: [ tg0, tg1, tg2, tg3 ]
+
+  io-channels:
+    maxItems: 1
+    description:
+      ADC channel connected to the MUXOUT pin for monitoring output voltage,
+      load current sense, and die temperature.
+
+  io-channel-names:
+    const: muxout
+
+  vdd-supply:
+    description: Digital power supply (1.08V to 1.98V)
+
+  avdd-supply:
+    description: Analog power supply (4.75V to 5.25V)
+
+  hvdd-supply:
+    description:
+      High voltage positive supply (7V to 45V). Supply voltage should be chosen
+      based on configured output ranges (see datasheet Table 9).
+
+  hvss-supply:
+    description:
+      High voltage negative supply (-22.5V to 0V). Required only when using
+      bipolar output ranges (±5V, ±10V, ±15V, ±20V). Supply voltage should be
+      chosen based on configured output ranges (see datasheet Table 9).
+
+  vref-supply:
+    description:
+      External voltage reference supply (4.056V to 4.136V, typically 4.096V).
+      When specified, the device uses external reference mode and the VREF pin
+      becomes an input. The device uses the internal 4.096V precision reference
+      otherwise.
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^channel@([0-9a-f])$":
+    type: object
+    description: Child nodes for individual channel configuration
+
+    properties:
+      reg:
+        description: Channel number.
+        minimum: 0
+        maximum: 15
+
+      adi,output-range-microvolt:
+        description: |
+          Output voltage range for this channel as [min, max] in microvolts.
+          If not specified, defaults to 0V to 5V range.
+        oneOf:
+          - items:
+              - const: 0
+              - enum: [5000000, 10000000, 20000000, 40000000]
+          - items:
+              - const: -5000000
+              - const: 5000000
+          - items:
+              - const: -10000000
+              - const: 10000000
+          - items:
+              - const: -15000000
+              - const: 15000000
+          - items:
+              - const: -20000000
+              - const: 20000000
+
+    required:
+      - reg
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - vdd-supply
+  - avdd-supply
+  - hvdd-supply
+
+dependencies:
+  spi-cpha: [ spi-cpol ]
+  spi-cpol: [ spi-cpha ]
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        dac@0 {
+            compatible = "adi,ad5529r-16";
+            reg = <0>;
+            spi-max-frequency = <25000000>;
+
+            vdd-supply = <&vdd_regulator>;
+            avdd-supply = <&avdd_regulator>;
+            hvdd-supply = <&hvdd_regulator>;
+            hvss-supply = <&hvss_regulator>;
+
+            reset-gpios = <&gpio0 87 GPIO_ACTIVE_LOW>;
+
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            channel@0 {
+                reg = <0>;
+                adi,output-range-microvolt = <0 5000000>;
+            };
+
+            channel@1 {
+                reg = <1>;
+                adi,output-range-microvolt = <(-10000000) 10000000>;
+            };
+
+            channel@2 {
+                reg = <2>;
+                adi,output-range-microvolt = <0 40000000>;
+            };
+        };
+    };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index d6c3c7d22403..320e84765ce6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1507,6 +1507,13 @@ W:	https://ez.analog.com/linux-software-drivers
 F:	Documentation/devicetree/bindings/iio/adc/adi,ad4851.yaml
 F:	drivers/iio/adc/ad4851.c
 
+ANALOG DEVICES INC AD5529R DRIVER
+M:	Janani Sunil <janani.sunil@analog.com>
+L:	linux-iio@vger.kernel.org
+S:	Supported
+W:	https://ez.analog.com/linux-software-drivers
+F:	Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
+
 ANALOG DEVICES INC AD5706R DRIVER
 M:	Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
 L:	linux-iio@vger.kernel.org

-- 
2.43.0

[PATCH v4 2/2] iio: dac: Add AD5529R DAC driver support

[Janani Sunil]

Add support for AD5529R 16-channel, 12/16 bit Digital to Analog Converter

Signed-off-by: Janani Sunil <janani.sunil@analog.com>
---
 MAINTAINERS               |   1 +
 drivers/iio/dac/Kconfig   |  17 ++
 drivers/iio/dac/Makefile  |   1 +
 drivers/iio/dac/ad5529r.c | 517 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 536 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 320e84765ce6..143714e27d51 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1513,6 +1513,7 @@ L:	linux-iio@vger.kernel.org
 S:	Supported
 W:	https://ez.analog.com/linux-software-drivers
 F:	Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
+F:	drivers/iio/dac/ad5529r.c
 
 ANALOG DEVICES INC AD5706R DRIVER
 M:	Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index 657c68e75542..bb1d59889a2a 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -134,6 +134,23 @@ config AD5449
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5449.
 
+config AD5529R
+	tristate "Analog Devices AD5529R High Voltage DAC driver"
+	depends on SPI_MASTER
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices AD5529R
+	  16-Channel, 12-Bit/16-Bit, 40V High Voltage Precision Digital to Analog
+	  Converter.
+
+	  The device features multiple output voltage ranges from -20V to +20V,
+	  built-in 4.096V voltage reference, and digital functions including
+	  toggle, dither, and ramp modes. Supports both 12-bit and 16-bit
+	  resolution variants.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad5529r.
+
 config AD5592R_BASE
 	tristate
 
diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
index 003431798498..f35e060b3643 100644
--- a/drivers/iio/dac/Makefile
+++ b/drivers/iio/dac/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_AD5446) += ad5446.o
 obj-$(CONFIG_AD5446_SPI) += ad5446-spi.o
 obj-$(CONFIG_AD5446_I2C) += ad5446-i2c.o
 obj-$(CONFIG_AD5449) += ad5449.o
+obj-$(CONFIG_AD5529R) += ad5529r.o
 obj-$(CONFIG_AD5592R_BASE) += ad5592r-base.o
 obj-$(CONFIG_AD5592R) += ad5592r.o
 obj-$(CONFIG_AD5593R) += ad5593r.o
diff --git a/drivers/iio/dac/ad5529r.c b/drivers/iio/dac/ad5529r.c
new file mode 100644
index 000000000000..d2d0287d0f95
--- /dev/null
+++ b/drivers/iio/dac/ad5529r.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AD5529R Digital-to-Analog Converter Driver
+ * 16-Channel, 12/16-Bit, 40V High Voltage Precision DAC
+ *
+ * Copyright 2026 Analog Devices Inc.
+ * Author: Janani Sunil <janani.sunil@analog.com>
+ */
+
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/dev_printk.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/iio/iio.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+#include <linux/spi/spi.h>
+
+#define AD5529R_REG_INTERFACE_CONFIG_A		0x00
+#define AD5529R_REG_DEVICE_CONFIG		0x02
+#define AD5529R_REG_CHIP_GRADE			0x06
+#define AD5529R_REG_SCRATCH_PAD			0x0A
+#define AD5529R_REG_SPI_REVISION		0x0B
+#define AD5529R_REG_VENDOR_H			0x0D
+#define AD5529R_REG_STREAM_MODE			0x0E
+#define AD5529R_REG_INTERFACE_STATUS_A		0x11
+#define AD5529R_REG_MULTI_DAC_CH_SEL		0x14
+#define AD5529R_REG_OUT_RANGE_BASE		0x3C
+#define AD5529R_REG_OUT_RANGE(ch)		(AD5529R_REG_OUT_RANGE_BASE + (ch) * 2)
+#define AD5529R_REG_DAC_INPUT_A_BASE		0x148
+#define AD5529R_REG_DAC_INPUT_A(ch)		(AD5529R_REG_DAC_INPUT_A_BASE + (ch) * 2)
+#define AD5529R_REG_DAC_DATA_READBACK_BASE	0x16A
+#define AD5529R_REG_TSENS_ALERT_FLAG		0x18C
+#define AD5529R_REG_TSENS_SHTD_FLAG		0x18E
+#define AD5529R_REG_FUNC_BUSY			0x1A0
+#define AD5529R_REG_REF_SEL			0x1A2
+#define AD5529R_REG_INIT_CRC_ERR_STAT		0x1A4
+#define AD5529R_REG_MULTI_DAC_HOTPATH_SW_LDAC	0x1A8
+
+#define   AD5529R_INTERFACE_CONFIG_A_SW_RESET	(BIT(7) | BIT(0))
+#define   AD5529R_INTERFACE_CONFIG_A_ADDR_ASCENSION	BIT(5)
+#define   AD5529R_INTERFACE_CONFIG_A_SDO_ENABLE	BIT(4)
+#define   AD5529R_REF_SEL_INTERNAL_REF		BIT(0)
+#define   AD5529R_MAX_REGISTER			0x232
+#define   AD5529R_8BIT_REG_MAX			0x13
+#define   AD5529R_SPI_READ_FLAG			0x80
+
+struct ad5529r_model_data {
+	const char *model_name;
+	unsigned int resolution;
+	const struct iio_chan_spec *channels;
+	unsigned int num_channels;
+};
+
+#define AD5529R_DAC_CHANNEL(chan, bits) {			\
+	.type = IIO_VOLTAGE,					\
+	.indexed = 1,						\
+	.output = 1,						\
+	.channel = (chan),					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
+			      BIT(IIO_CHAN_INFO_SCALE) |	\
+			      BIT(IIO_CHAN_INFO_OFFSET),	\
+	.scan_type = {						\
+		.format = 'u',					\
+		.realbits = (bits),				\
+		.storagebits = 16,				\
+	},							\
+}
+
+static const char * const ad5529r_supply_names[] = {
+	"vdd",
+	"avdd",
+	"hvdd",
+};
+
+static const struct iio_chan_spec ad5529r_channels_16bit[] = {
+	AD5529R_DAC_CHANNEL(0, 16),
+	AD5529R_DAC_CHANNEL(1, 16),
+	AD5529R_DAC_CHANNEL(2, 16),
+	AD5529R_DAC_CHANNEL(3, 16),
+	AD5529R_DAC_CHANNEL(4, 16),
+	AD5529R_DAC_CHANNEL(5, 16),
+	AD5529R_DAC_CHANNEL(6, 16),
+	AD5529R_DAC_CHANNEL(7, 16),
+	AD5529R_DAC_CHANNEL(8, 16),
+	AD5529R_DAC_CHANNEL(9, 16),
+	AD5529R_DAC_CHANNEL(10, 16),
+	AD5529R_DAC_CHANNEL(11, 16),
+	AD5529R_DAC_CHANNEL(12, 16),
+	AD5529R_DAC_CHANNEL(13, 16),
+	AD5529R_DAC_CHANNEL(14, 16),
+	AD5529R_DAC_CHANNEL(15, 16),
+};
+
+static const struct iio_chan_spec ad5529r_channels_12bit[] = {
+	AD5529R_DAC_CHANNEL(0, 12),
+	AD5529R_DAC_CHANNEL(1, 12),
+	AD5529R_DAC_CHANNEL(2, 12),
+	AD5529R_DAC_CHANNEL(3, 12),
+	AD5529R_DAC_CHANNEL(4, 12),
+	AD5529R_DAC_CHANNEL(5, 12),
+	AD5529R_DAC_CHANNEL(6, 12),
+	AD5529R_DAC_CHANNEL(7, 12),
+	AD5529R_DAC_CHANNEL(8, 12),
+	AD5529R_DAC_CHANNEL(9, 12),
+	AD5529R_DAC_CHANNEL(10, 12),
+	AD5529R_DAC_CHANNEL(11, 12),
+	AD5529R_DAC_CHANNEL(12, 12),
+	AD5529R_DAC_CHANNEL(13, 12),
+	AD5529R_DAC_CHANNEL(14, 12),
+	AD5529R_DAC_CHANNEL(15, 12),
+};
+
+static const struct ad5529r_model_data ad5529r_16bit_model_data = {
+	.model_name = "ad5529r-16",
+	.resolution = 16,
+	.channels = ad5529r_channels_16bit,
+	.num_channels = ARRAY_SIZE(ad5529r_channels_16bit),
+};
+
+static const struct ad5529r_model_data ad5529r_12bit_model_data = {
+	.model_name = "ad5529r-12",
+	.resolution = 12,
+	.channels = ad5529r_channels_12bit,
+	.num_channels = ARRAY_SIZE(ad5529r_channels_12bit),
+};
+
+enum ad5529r_output_range {
+	AD5529R_RANGE_0V_5V,
+	AD5529R_RANGE_0V_10V,
+	AD5529R_RANGE_0V_20V,
+	AD5529R_RANGE_0V_40V,
+	AD5529R_RANGE_NEG5V_5V,
+	AD5529R_RANGE_NEG10V_10V,
+	AD5529R_RANGE_NEG15V_15V,
+	AD5529R_RANGE_NEG20V_20V,
+};
+
+static const s32 ad5529r_output_ranges_mv[8][2] = {
+	[AD5529R_RANGE_0V_5V] = { 0, 5000 },
+	[AD5529R_RANGE_0V_10V] = { 0, 10000 },
+	[AD5529R_RANGE_0V_20V] = { 0, 20000 },
+	[AD5529R_RANGE_0V_40V] = { 0, 40000 },
+	[AD5529R_RANGE_NEG5V_5V] = { -5000, 5000 },
+	[AD5529R_RANGE_NEG10V_10V] = { -10000, 10000 },
+	[AD5529R_RANGE_NEG15V_15V] = { -15000, 15000 },
+	[AD5529R_RANGE_NEG20V_20V] = { -20000, 20000 },
+};
+
+struct ad5529r_state {
+	struct spi_device *spi;
+	const struct ad5529r_model_data *model_data;
+	struct regmap *regmap_8bit;
+	struct regmap *regmap_16bit;
+	enum ad5529r_output_range output_range_idx[16];
+};
+
+static const struct regmap_range ad5529r_8bit_readable_ranges[] = {
+	regmap_reg_range(AD5529R_REG_INTERFACE_CONFIG_A, AD5529R_REG_CHIP_GRADE),
+	regmap_reg_range(AD5529R_REG_SCRATCH_PAD, AD5529R_REG_VENDOR_H),
+	regmap_reg_range(AD5529R_REG_STREAM_MODE, AD5529R_REG_INTERFACE_STATUS_A),
+};
+
+static const struct regmap_range ad5529r_16bit_readable_ranges[] = {
+	regmap_reg_range(AD5529R_REG_MULTI_DAC_CH_SEL, AD5529R_REG_INIT_CRC_ERR_STAT),
+	regmap_reg_range(AD5529R_REG_MULTI_DAC_HOTPATH_SW_LDAC, AD5529R_MAX_REGISTER),
+};
+
+static const struct regmap_access_table ad5529r_8bit_readable_table = {
+	.yes_ranges = ad5529r_8bit_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(ad5529r_8bit_readable_ranges),
+};
+
+static const struct regmap_access_table ad5529r_16bit_readable_table = {
+	.yes_ranges = ad5529r_16bit_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(ad5529r_16bit_readable_ranges),
+};
+
+static const struct regmap_range ad5529r_8bit_read_only_ranges[] = {
+	regmap_reg_range(AD5529R_REG_DEVICE_CONFIG, AD5529R_REG_CHIP_GRADE),
+	regmap_reg_range(AD5529R_REG_SPI_REVISION, AD5529R_REG_VENDOR_H),
+};
+
+static const struct regmap_range ad5529r_16bit_read_only_ranges[] = {
+	regmap_reg_range(AD5529R_REG_DAC_DATA_READBACK_BASE,
+			 (AD5529R_REG_DAC_DATA_READBACK_BASE + 15 * 2)),
+	regmap_reg_range(AD5529R_REG_TSENS_ALERT_FLAG, AD5529R_REG_TSENS_SHTD_FLAG),
+	regmap_reg_range(AD5529R_REG_FUNC_BUSY, AD5529R_REG_FUNC_BUSY),
+	regmap_reg_range(AD5529R_REG_INIT_CRC_ERR_STAT, AD5529R_REG_INIT_CRC_ERR_STAT),
+};
+
+static const struct regmap_access_table ad5529r_8bit_writeable_table = {
+	.no_ranges = ad5529r_8bit_read_only_ranges,
+	.n_no_ranges = ARRAY_SIZE(ad5529r_8bit_read_only_ranges),
+};
+
+static const struct regmap_access_table ad5529r_16bit_writeable_table = {
+	.no_ranges = ad5529r_16bit_read_only_ranges,
+	.n_no_ranges = ARRAY_SIZE(ad5529r_16bit_read_only_ranges),
+};
+
+static const struct regmap_config ad5529r_regmap_8bit_config = {
+	.name = "ad5529r-8bit",
+	.reg_bits = 16,
+	.val_bits = 8,
+	.max_register = AD5529R_8BIT_REG_MAX,
+	.read_flag_mask = AD5529R_SPI_READ_FLAG,
+	.rd_table = &ad5529r_8bit_readable_table,
+	.wr_table = &ad5529r_8bit_writeable_table,
+};
+
+static const struct regmap_config ad5529r_regmap_16bit_config = {
+	.name = "ad5529r-16bit",
+	.reg_bits = 16,
+	.val_bits = 16,
+	.max_register = AD5529R_MAX_REGISTER,
+	.read_flag_mask = AD5529R_SPI_READ_FLAG,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+	.rd_table = &ad5529r_16bit_readable_table,
+	.wr_table = &ad5529r_16bit_writeable_table,
+	.reg_stride = 2,
+};
+
+static struct regmap *ad5529r_get_regmap(struct ad5529r_state *st,
+					 unsigned int reg)
+{
+	if (reg <= AD5529R_8BIT_REG_MAX)
+		return st->regmap_8bit;
+
+	return st->regmap_16bit;
+}
+
+static int ad5529r_reset(struct ad5529r_state *st)
+{
+	struct reset_control *rst;
+	int ret;
+
+	rst = devm_reset_control_get_optional_exclusive(&st->spi->dev, NULL);
+	if (IS_ERR(rst))
+		return PTR_ERR(rst);
+
+	if (rst) {
+		ret = reset_control_deassert(rst);
+		if (ret)
+			return ret;
+	} else {
+		ret = regmap_write(st->regmap_8bit, AD5529R_REG_INTERFACE_CONFIG_A,
+				   AD5529R_INTERFACE_CONFIG_A_SW_RESET);
+		if (ret)
+			return ret;
+	}
+
+	/*
+	 * Wait 10 ms for digital initialization to complete.
+	 * Per datasheet, Interface Status A register NOT_READY_ERR bit is
+	 * set if SPI transactions are attempted before digital initialization
+	 * completes.
+	 */
+	fsleep(10000);
+
+	return regmap_write(st->regmap_8bit, AD5529R_REG_INTERFACE_CONFIG_A,
+			    AD5529R_INTERFACE_CONFIG_A_SDO_ENABLE |
+			    AD5529R_INTERFACE_CONFIG_A_ADDR_ASCENSION);
+}
+
+static int ad5529r_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct ad5529r_state *st = iio_priv(indio_dev);
+	unsigned int reg_addr, reg_val_h;
+	int ret, range_idx, span_mv;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		/*
+		 * Read from DAC_INPUT_A register rather than DAC_DATA_READBACK.
+		 * The DAC operates in transparent mode and directly reflects
+		 * whatever value is written to the INPUT_A register.
+		 */
+		reg_addr = AD5529R_REG_DAC_INPUT_A(chan->channel);
+		ret = regmap_read(st->regmap_16bit, reg_addr, &reg_val_h);
+		if (ret)
+			return ret;
+
+		*val = reg_val_h;
+
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		range_idx = st->output_range_idx[chan->channel];
+
+		span_mv = ad5529r_output_ranges_mv[range_idx][1] -
+			  ad5529r_output_ranges_mv[range_idx][0];
+		*val = span_mv;
+		*val2 = st->model_data->resolution;
+
+		return IIO_VAL_FRACTIONAL_LOG2;
+	case IIO_CHAN_INFO_OFFSET:
+		range_idx = st->output_range_idx[chan->channel];
+
+		if (ad5529r_output_ranges_mv[range_idx][0] < 0)
+			*val = -(1 << (st->model_data->resolution - 1));
+		else
+			*val = 0;
+
+		return IIO_VAL_INT;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ad5529r_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct ad5529r_state *st = iio_priv(indio_dev);
+	unsigned int reg_addr;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (val < 0 || val > GENMASK(st->model_data->resolution - 1, 0))
+			return -EINVAL;
+
+		reg_addr = AD5529R_REG_DAC_INPUT_A(chan->channel);
+
+		return regmap_write(st->regmap_16bit, reg_addr, val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ad5529r_find_output_range(const s32 *vals)
+{
+	for (unsigned int i = 0; i < ARRAY_SIZE(ad5529r_output_ranges_mv); i++) {
+		if (vals[0] == ad5529r_output_ranges_mv[i][0] * 1000 &&
+		    vals[1] == ad5529r_output_ranges_mv[i][1] * 1000)
+			return i;
+	}
+
+	return -EINVAL;
+}
+
+static int ad5529r_parse_channel_ranges(struct device *dev,
+					struct ad5529r_state *st)
+{
+	int ret, range_idx;
+	u32 ch;
+	s32 vals[2];
+
+	device_for_each_child_node_scoped(dev, child) {
+		range_idx = AD5529R_RANGE_0V_5V;
+
+		ret = fwnode_property_read_u32(child, "reg", &ch);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Missing reg property in channel node\n");
+
+		if (ch >= 16)
+			return dev_err_probe(dev, -EINVAL,
+					     "Invalid channel number: %u\n", ch);
+
+		/* Read u32 property into s32 to handle negative voltage ranges */
+		if (!fwnode_property_read_u32_array(child,
+						    "adi,output-range-microvolt",
+						    (u32 *)vals, ARRAY_SIZE(vals))) {
+			range_idx = ad5529r_find_output_range(vals);
+			if (range_idx < 0)
+				return dev_err_probe(dev, range_idx,
+						     "Invalid range [%d %d] for ch %u\n",
+						     vals[0], vals[1], ch);
+		}
+
+		st->output_range_idx[ch] = range_idx;
+		ret = regmap_write(st->regmap_16bit,
+				   AD5529R_REG_OUT_RANGE(ch), range_idx);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Failed to configure range for ch %u\n",
+					     ch);
+	}
+
+	return 0;
+}
+
+static int ad5529r_reg_access(struct iio_dev *indio_dev,
+			      unsigned int reg,
+			      unsigned int writeval,
+			      unsigned int *readval)
+{
+	struct ad5529r_state *st = iio_priv(indio_dev);
+
+	if (readval)
+		return regmap_read(ad5529r_get_regmap(st, reg), reg, readval);
+
+	return regmap_write(ad5529r_get_regmap(st, reg), reg, writeval);
+}
+
+static const struct iio_info ad5529r_info = {
+	.read_raw = ad5529r_read_raw,
+	.write_raw = ad5529r_write_raw,
+	.debugfs_reg_access = ad5529r_reg_access,
+};
+
+static int ad5529r_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct iio_dev *indio_dev;
+	struct ad5529r_state *st;
+	bool external_vref;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+
+	st->spi = spi;
+
+	st->model_data = spi_get_device_match_data(spi);
+	if (!st->model_data)
+		return dev_err_probe(dev, -EINVAL, "Failed to identify device variant\n");
+
+	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(ad5529r_supply_names),
+					     ad5529r_supply_names);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Failed to get and enable regulators\n");
+
+	ret = devm_regulator_get_enable_optional(dev, "hvss");
+	if (ret && ret != -ENODEV)
+		return dev_err_probe(dev, ret,
+				     "Failed to get and enable hvss regulator\n");
+
+	/*
+	 * The datasheet mentions a 4.096V external reference for correct
+	 * operation.
+	 */
+	ret = devm_regulator_get_enable_optional(dev, "vref");
+	if (ret && ret != -ENODEV)
+		return dev_err_probe(dev, ret,
+				     "Failed to get and enable vref regulator\n");
+
+	external_vref = ret != -ENODEV;
+
+	st->regmap_8bit = devm_regmap_init_spi(spi, &ad5529r_regmap_8bit_config);
+	if (IS_ERR(st->regmap_8bit))
+		return dev_err_probe(dev, PTR_ERR(st->regmap_8bit),
+				     "Failed to initialize 8-bit regmap\n");
+
+	st->regmap_16bit = devm_regmap_init_spi(spi, &ad5529r_regmap_16bit_config);
+	if (IS_ERR(st->regmap_16bit))
+		return dev_err_probe(dev, PTR_ERR(st->regmap_16bit),
+				     "Failed to initialize 16-bit regmap\n");
+
+	ret = ad5529r_reset(st);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to reset device\n");
+
+	ret = regmap_assign_bits(st->regmap_16bit, AD5529R_REG_REF_SEL,
+				 AD5529R_REF_SEL_INTERNAL_REF,
+				 external_vref ? 0 : AD5529R_REF_SEL_INTERNAL_REF);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to configure reference\n");
+
+	ret = ad5529r_parse_channel_ranges(dev, st);
+	if (ret)
+		return ret;
+
+	indio_dev->name = st->model_data->model_name;
+	indio_dev->info = &ad5529r_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = st->model_data->channels;
+	indio_dev->num_channels = st->model_data->num_channels;
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id ad5529r_of_match[] = {
+	{ .compatible = "adi,ad5529r-16", .data = &ad5529r_16bit_model_data },
+	{ .compatible = "adi,ad5529r-12", .data = &ad5529r_12bit_model_data },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ad5529r_of_match);
+
+static const struct spi_device_id ad5529r_id[] = {
+	{
+		.name = "ad5529r-16",
+		.driver_data = (kernel_ulong_t)&ad5529r_16bit_model_data,
+	},
+	{
+		.name = "ad5529r-12",
+		.driver_data = (kernel_ulong_t)&ad5529r_12bit_model_data,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, ad5529r_id);
+
+static struct spi_driver ad5529r_driver = {
+	.driver = {
+		.name = "ad5529r",
+		.of_match_table = ad5529r_of_match,
+	},
+	.probe = ad5529r_probe,
+	.id_table = ad5529r_id,
+};
+module_spi_driver(ad5529r_driver);
+
+MODULE_AUTHOR("Janani Sunil <janani.sunil@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD5529R 12/16-bit DAC driver");
+MODULE_LICENSE("GPL");

-- 
2.43.0

Re: [PATCH v4 2/2] iio: dac: Add AD5529R DAC driver support

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The hardware reset logic fails to guarantee a reset pulse and skips software reset, breaking module reload.
--

commit e9e9fe5da17e349af411f3cecc999fcff44de1e2
Author: Janani Sunil <janani.sunil@analog.com>

iio: dac: Add AD5529R DAC driver support

This commit adds driver support for the Analog Devices AD5529R 16-channel,
12/16-bit DAC. It provides basic IIO voltage output capabilities and supports
configuring output ranges.

> diff --git a/drivers/iio/dac/ad5529r.c b/drivers/iio/dac/ad5529r.c
> new file mode 100644
> index 0000000000000..d2d0287d0f951
> --- /dev/null
> +++ b/drivers/iio/dac/ad5529r.c

[ ... ]

> +static int ad5529r_reset(struct ad5529r_state *st)
> +{
> +	struct reset_control *rst;
> +	int ret;
> +
> +	rst = devm_reset_control_get_optional_exclusive(&st->spi->dev, NULL);
> +	if (IS_ERR(rst))
> +		return PTR_ERR(rst);
> +
> +	if (rst) {
> +		ret = reset_control_deassert(rst);
> +		if (ret)
> +			return ret;
> +	} else {
> +		ret = regmap_write(st->regmap_8bit, AD5529R_REG_INTERFACE_CONFIG_A,
> +				   AD5529R_INTERFACE_CONFIG_A_SW_RESET);
> +		if (ret)
> +			return ret;
> +	}

[Severity: High]
Does this code ensure the device is actually reset on driver reload?

If the driver is unbound and rebound, the hardware reset line might already
be deasserted. Since reset_control_deassert() is called without a prior
assert, and there is no teardown action registered to assert the line on
unbind, will the device fail to receive a physical reset pulse?

Because a hardware reset control is present, the software reset in the else
block is also skipped. Could this combination leave the device in an
unpredictable state on subsequent probes?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260609-ad5529r-driver-v4-0-2e4c02234a1a@analog.com?part=2

Re: [PATCH v4 1/2] dt-bindings: iio: dac: Add AD5529R

[Conor Dooley]

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Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

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