[PATCH v3 0/2] hwmon: (fs1603) Add driver for TDK FS160x and FS1006 uPOL converters

[Kevin Jia]

The TDK FS1603, FS1604, FS1606 and FS1006 are uPOL DC-DC converters with
an integrated inductor. They report input and output voltage, output
current and temperature over a proprietary I2C register map. They are not
PMBus devices, and their register numbers collide with PMBus command codes.

Patch 1 adds a devicetree binding, and patch 2 adds a read-only hwmon
driver. The model cannot be detected from the part, so it is declared
through the I2C device name or the devicetree compatible. Parts that
encode telemetry like the FS1603 list tdk,fs1603 as a fallback.

The TDK vendor prefix is added by the FS1412 series, which this series
depends on:
https://lore.kernel.org/all/20261020-hwmon-pmbus-fs1412-v4-0-27ece4e43d04@xxxxxxxxxx/

Tested on FS1603, FS1604, FS1006-3300, FS1006-5000 and FS1606-0600 parts
with the driver backported to 6.12.

Signed-off-by: Kevin Jia <kjia@xxxxxxxxxx>
---
Changes in v3:
- Drop the vendor-prefixes patch, the TDK prefix is added by the FS1412
  series (Guenter).
- dt-bindings: Move to a dedicated tdk,fs1603.yaml, where the FS1604,
  FS1006-3300, FS1006-5000 and FS1606-2500 fall back to tdk,fs1603
  (Krzysztof, Guenter).
- hwmon: Drop the OCSet probe check. OCSet is a programmable over-current
  level and not really an ID, so it warned falsely on boards that
  reprogram it.
- hwmon: Match only tdk,fs1603, tdk,fs1606 and tdk,fs1606-0600, and share
  driver data between parts that encode telemetry the same way (Guenter).
- Link to v2: https://patch.msgid.link/20261020-fs1603-v2-0-0986107a5cd2@xxxxxxxxxx

Changes in v2:
- hwmon: Scale in1_crit by the feedback divider ratio measured at probe.
  Further testing after v1 found that on boards that raise the rail with a
  feedback divider, as the FS1606-0600 is used, VOUT_SET holds the 0.6 V
  feedback target while VOUT reports the rail, so v1 reported the
  feedback-pin trip point (about 0.72 V) as in1_crit on every such rail.
- hwmon: Use named initializers in fs1603_id[] (Sashiko).
- Link to v1: https://patch.msgid.link/20261019-fs1603-v1-0-8adf972386c1@xxxxxxxxxx

---
Kevin Jia (2):
      dt-bindings: hwmon: Add TDK FS160x and FS1006
      hwmon: (fs1603) Add driver for TDK FS160x and FS1006 uPOL converters

 .../devicetree/bindings/hwmon/tdk,fs1603.yaml      |  53 +++
 Documentation/hwmon/fs1603.rst                     |  75 ++++
 Documentation/hwmon/index.rst                      |   1 +
 MAINTAINERS                                        |   8 +
 drivers/hwmon/Kconfig                              |  11 +
 drivers/hwmon/Makefile                             |   1 +
 drivers/hwmon/fs1603.c                             | 498 +++++++++++++++++++++
 7 files changed, 647 insertions(+)
---
base-commit: 400be69515c327ced60082b27ede902a8d93cbdb
change-id: 20261016-fs1603-25483c5edc57
prerequisite-message-id: <20261020-hwmon-pmbus-fs1412-v4-0-27ece4e43d04@xxxxxxxxxx>
prerequisite-patch-id: 48986e9a4b228cab399cc8b28ab5cebedebbca09
prerequisite-patch-id: e9d346bc8703fcb8032b663bddb7514ce31f2c1c
prerequisite-patch-id: 460dc5083895fdd9fc430ce886736561151571bf
prerequisite-patch-id: 34cc05e38fdf5462d315c20f186a2c2904a572f2

Best regards,
--  
Kevin Jia <kjia@xxxxxxxxxx>