linux-kernel - [PATCH v3 0/2] Adding support for Microchip MCP47FEB02

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Message-ID: <20251209-mcp47feb02-v3-0-bb0ba9052f4f@microchip.com>
Date: Tue, 9 Dec 2025 18:06:22 +0200
From: Ariana Lazar <ariana.lazar@...rochip.com>
To: Ariana Lazar <ariana.lazar@...rochip.com>, Jonathan Cameron
	<jic23@...nel.org>, David Lechner <dlechner@...libre.com>,
	Nuno Sá <nuno.sa@...log.com>, Andy Shevchenko
	<andy@...nel.org>, Rob Herring <robh@...nel.org>, Krzysztof Kozlowski
	<krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>
CC: <linux-iio@...r.kernel.org>, <devicetree@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>, Conor Dooley <conor.dooley@...rochip.com>
Subject: [PATCH v3 0/2] Adding support for Microchip MCP47FEB02

Adding support for Microchip MCP47F(E/V)B(0/1/2)1, MCP47F(E/V)B(0/1/2)2,
MCP47F(E/V)B(0/1/2)4 and MCP47F(E/V)B(0/1/2)8 series of buffered voltage
output Digital-to-Analog converters with an I2C Interface. This driver
covers the following part numbers:
 - With nonvolatile memory:
   - MCP47FEB01, MCP47FEB11, MCP47FEB21, MCP47FEB02, MCP47FEB12,
   - MCP47FEB22, MCP47FEB04, MCP47FEB14, MCP47FEB24, MCP47FEB08,
     MCP47FEB18, MCP47FEB28
 - With volatile memory:
   - MCP47FVB01, MCP47FVB11, MCP47FVB21, MCP47FVB02, MCP47FVB12,
     MCP47FVB22, MCP47FVB04, MCP47FVB14, MCP47FVB24, MCP47FVB08,
     MCP47FVB18, MCP47FVB28

The families support up to 8 output channels. The devices can be 8-bit,
10-bit and 12-bit resolution.

---
Changes in v3:
- fix review comments driver:
    run pahole on mcp47feb02_features, mcp47feb02_channel_data and
      mcp47feb02_data structs
    rephase comment with datasheet links
    add missing include files
    remove shift operations from defines and provided the shifted values
      instead
    remove MCP47FEB02_DELAY_1_MS define, renamed _MV to _mV
    correct style issue in struct definition 
    remove fwnode_property_present
    protect setting active mask bits operation with mutex
    use unsigned int instead of int where possible
    use IIO_DEVICE_ATTR_WO() for store_eeprom instead of IIO_DEVICE_ATTR()
    refractor Kconfig entry for better visibility
- Link to v2: https://lore.kernel.org/r/20251103-mcp47feb02-v2-0-8c37741bd97a@microchip.com

Changes in v2:
v2:
- fix review comments device tree binding:
    corrected the use of patternProperties and enum with an array of
      channel numbers instead of minimum/maximum
    gave more specific names to the labels of the channels
    removed '|' from where it was unneccesarry
    removed unneccesarry setting of attributes to true

- fix review comments driver:
    replace custom write function with regmap_update_bits.
    add read_flag_mask field to regmap_config struct and shifted all
       register addresses with 3 bits in order to correctly apply R/W
       command mask
    change cache_type field of regmap_config structs to REGCACHE_MAPLE
    add val_format_endian field to regmap_config struct as
       REGMAP_ENDIAN_BIG
    keep in powerdown_mode last value written to register before reloading
       the driver
    create defines for magic bits used in probe function
    remove unneccesarry channel enabled checks
    add in parse_fw initialization of reg with 0, check for valid
    reg number after reading it from devicetree and nonzero num_channels
    initialize vref_mv, vref1_mv, vdd_mv
    replace CH_0, ... CH_7 masks with DAC_CTRL_BITS(ch) and  G_0, ... G_7
      with DAC_GAIN_BIT(ch)
    correct write_powerdown function to write normal operation into
      specific bit mask from power-down register when a channel exits
      power-down mode.
    add const pointer to info in data struct
    delete device_property_present checks for vref, vref1. Read vref1 only
      if have_ext_vref1 is present in features
    protect write operations with mutex using scoped_guard or guard
    refactor probe function by creating 2 setup functions,
      mcp47feb02_init_ctrl_regs and mcp47feb02_init_ch_scales.
    correct info/debug messages where it was specified
    use devm_iio_device_register and deleted remove() function
    in write_raw only update struct data if regmap write succeeds

v1:
- first version committed to review
- Link to v1: https://lore.kernel.org/r/20250922-mcp47feb02-v1-0-06cb4acaa347@microchip.com

Signed-off-by: Ariana Lazar <ariana.lazar@...rochip.com>

---
Ariana Lazar (2):
      dt-bindings: iio: dac: adding support for Microchip MCP47FEB02
      iio: dac: adding support for Microchip MCP47FEB02

 .../bindings/iio/dac/microchip,mcp47feb02.yaml     |  302 +++++
 MAINTAINERS                                        |    7 +
 drivers/iio/dac/Kconfig                            |   17 +
 drivers/iio/dac/Makefile                           |    1 +
 drivers/iio/dac/mcp47feb02.c                       | 1254 ++++++++++++++++++++
 5 files changed, 1581 insertions(+)
---
base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494
change-id: 20250825-mcp47feb02-31c77857ae29

Best regards,
-- 
Ariana Lazar <ariana.lazar@...rochip.com>