iio: adc: add Nuvoton NCT7201 ADC driver

Change since version 10:
- Fix comments
- Add interrupt handler function to call iio_push_event()

Change since version 9:
- Fix comments
- Change vin_mask and mask from CPU-endian to little-endian
- Fix access to restricted __le16

Change since version 8:
- dev_err_probe(), move the definition from device.h to dev_printk.h
- Use USEC_PER_MSEC rather than the hard coded value of 1000
- Use one dev for both regmap and regmap16

Change since version 7:
- Fix comments
- Derive dev from the respective regmap
- Generate the mask from the number of voltage input channels

Change since version 6:
- Fix comments
- Add use_single_read in regmap_config
- Remove unused definitions
- Do not shadow the return code by -EIO and let regmap API caller to decide
- Use simple English in all error messages
- Use a local variable for the struct device pointers. This increases code readability with shortened lines.
- Use fsleep instead of mdelay
- Use 16 bits type __le16 instead of u8 data[2]

Change since version 5:
- Fix comments
- Add NUVOTON NCT7201 IIO DRIVER section in MAINTAINERS
- Add vdd-supply and vref-supply to the DT example
- Remove mutex since the regmap should already have an internal lock
- Remove redundant assigning values
- Check errors on regmap_write

Change since version 4:
- Fix comments
- Add interrupts and reset-gpios to the DT example
- Use the FIELD_PREP and FIELD_GET
- Add use_single_write in regmap_config
- Use regmap_access_table

Change since version 3:
- Fix comments
- Don't put nct720"x" in the name, just call it nct7201
- Remove differential inputs until conversions are finished
- Add NCT7201_ prefix in all macros and avoid the tables
- Correct event threshold values in raw units
- Add with and without interrupt callback function to have the event config part and one that doesn't
- Remove print an error message if regmap_wirte failed case

Change since version 2:
- Remvoe read-vin-data-size property, default use read word vin data
- Use regmap instead of i2c smbus API
- IIO should be IIO_CHAN_INFO_RAW and _SCALE not _PROCESSED
- Use dev_xxx_probe in probe function and dev_xxx in other functions
- Use devm_iio_device_register replace of iio_device_register
- Use guard(mutex) replace of mutex_lock
- Use get_unaligned_le16 conversion API

Changes since version 1:
- Add new property in iio:adc binding document
- Add new driver for Nuvoton NCT720x driver

Eason Yang (2):
dt-bindings: iio: adc: add NCT7201 ADCs
iio: adc: add support for Nuvoton NCT7201

 .../bindings/iio/adc/nuvoton,nct7201.yaml     |  70 +++
 MAINTAINERS                                   |   7 +
 drivers/iio/adc/Kconfig                       |  11 +
 drivers/iio/adc/Makefile                      |   1 +
 drivers/iio/adc/nct7201.c                     | 501 ++++++++++++++++++
 5 files changed, 590 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/nuvoton,nct7201.yaml
 create mode 100644 drivers/iio/adc/nct7201.c

2.34.1

Add a binding specification for the Nuvoton NCT7201/NCT7202 up to 12-bit ADCs with I2C interface.

---
 .../bindings/iio/adc/nuvoton,nct7201.yaml     | 70 +++++++++++++++++++
 MAINTAINERS                                   |  6 ++
 2 files changed, 76 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/adc/nuvoton,nct7201.yaml

new file mode 100644
index 000000000000..8ce7d415d956
@@ -0,0 +1,70 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/nuvoton,nct7201.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Nuvoton nct7201 and similar ADCs
+
+maintainers:
+  - Eason Yang <[email protected]>
+
+description: |
+  The NCT7201/NCT7202 is a Nuvoton Hardware Monitor IC, contains up to 12
+  voltage monitoring channels, with SMBus interface, and up to 4 sets SMBus
+  address selection by ADDR connection. It also provides ALERT# signal for
+  event notification and reset input RSTIN# to recover it from a fault
+  condition.
+
+  NCT7201 contains 8 voltage monitor inputs (VIN1~VIN8).
+  NCT7202 contains 12 voltage monitor inputs (VIN1~VIN12).
+
+properties:
+  compatible:
+    enum:
+      - nuvoton,nct7201
+      - nuvoton,nct7202
+
+  reg:
+    maxItems: 1
+
+  vdd-supply:
+    description:
+      A 3.3V to supply that powers the chip.
+
+  vref-supply:
+    description:
+      The regulator supply for the ADC reference voltage.
+
+  interrupts:
+    maxItems: 1
+
+  reset-gpios:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        adc@1d {
+            compatible = "nuvoton,nct7202";
+            reg = <0x1d>;
+            vdd-supply = <&vdd>;
+            vref-supply = <&vref>;
+            interrupt-parent = <&gpio3>;
+            interrupts = <30 IRQ_TYPE_LEVEL_LOW>;
+            reset-gpios = <&gpio3 28 GPIO_ACTIVE_LOW>;
+        };
+    };
+...

index f21f1dabb5fe..2e4000866a7c 100644
@@ -17432,6 +17432,12 @@ F:	drivers/nubus/
 F:	include/linux/nubus.h
 F:	include/uapi/linux/nubus.h
 
+NUVOTON NCT7201 IIO DRIVER
+M:	Eason Yang <[email protected]>
+L:	[email protected]
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/adc/nuvoton,nct7201.yaml
+
 NVIDIA (rivafb and nvidiafb) FRAMEBUFFER DRIVER
 M:	Antonino Daplas <[email protected]>
 L:	[email protected]

2.34.1

Add Nuvoton NCT7201/NCT7202 system voltage monitor 12-bit ADC driver

NCT7201/NCT7202 supports up to 12 analog voltage monitor inputs and up to 4 SMBus addresses by ADDR pin. Meanwhile, ALERT# hardware event pins for independent alarm signals, and all the threshold values could be set for system protection without any timing delay. It also supports reset input RSTIN# to recover system from a fault condition.

Currently, only single-edge mode conversion and threshold events are supported.

---
 MAINTAINERS               |   1 +
 drivers/iio/adc/Kconfig   |  11 +
 drivers/iio/adc/Makefile  |   1 +
 drivers/iio/adc/nct7201.c | 501 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 514 insertions(+)
 create mode 100644 drivers/iio/adc/nct7201.c

index 2e4000866a7c..855ae5c19f92 100644
@@ -17437,6 +17437,7 @@ M:	Eason Yang <[email protected]>
 L:	[email protected]
 S:	Maintained
 F:	Documentation/devicetree/bindings/iio/adc/nuvoton,nct7201.yaml
+F:	drivers/iio/adc/nct7201.c
 
 NVIDIA (rivafb and nvidiafb) FRAMEBUFFER DRIVER
 M:	Antonino Daplas <[email protected]>

index 6529df1a498c..6d6af1b51b5e 100644
@@ -1092,6 +1092,17 @@ config NAU7802
 	  To compile this driver as a module, choose M here: the
 	  module will be called nau7802.
 
+config NCT7201
+	tristate "Nuvoton Instruments NCT7201 and NCT7202 Power Monitor"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  If you say yes here you get support for the Nuvoton NCT7201 and
+	  NCT7202 Voltage Monitor.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called nct7201.
+
 config NPCM_ADC
 	tristate "Nuvoton NPCM ADC driver"
 	depends on ARCH_NPCM || COMPILE_TEST

index 3e918c3eec69..54e8a7541af6 100644
@@ -97,6 +97,7 @@ obj-$(CONFIG_MESON_SARADC) += meson_saradc.o
 obj-$(CONFIG_MP2629_ADC) += mp2629_adc.o
 obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o
 obj-$(CONFIG_NAU7802) += nau7802.o
+obj-$(CONFIG_NCT7201) += nct7201.o
 obj-$(CONFIG_NPCM_ADC) += npcm_adc.o
 obj-$(CONFIG_PAC1921) += pac1921.o
 obj-$(CONFIG_PAC1934) += pac1934.o

2.34.1

LGTM,

With Best Regards,
Andy Shevchenko

Series applied to the testing branch of iio.git.
I'll push out as togreg once it's had some basic build testing.

thanks,

Jonathan