[PATCH v8 0/6] mfd: Add support for NXP MC33978/MC34978 MSDI

Oleksij Rempel
2026-03-29T09:06:25Z

changes v7:
- drop gpiolib irq fix and make pinctrl more robust against NULL point
dereference.

This series adds support for the NXP MC33978/MC34978 Multiple Switch Detection
Interface (MSDI) via the MFD framework.

Architecture overview:
* mfd: Core driver handling 2-frame pipelined SPI, regulator sequencing, and
linear irq_domain. Harvests status bits from SPI MISO MSB.
* pinctrl: Exposes 22 physical switch inputs as standard GPIOs. Proxies IRQs to
the MFD domain.
* hwmon: Exposes thermal limits, VBATP/VDDQ voltage boundaries, and dynamic
fault alarms.
* mux: Controls the 24-to-1 AMUX routing analog signals (switch voltages,
temperature, VBATP) to an external ADC.

Initial pinctrl implementation by David Jander, reworked into this MFD
architecture.

Best regards,
Oleksij

David Jander (1):
pinctrl: add NXP MC33978/MC34978 pinctrl driver

Oleksij Rempel (5):
dt-bindings: pinctrl: add NXP MC33978/MC34978 MSDI
mfd: add NXP MC33978/MC34978 core driver
pinctrl: core: Make pin group callbacks optional for pin-only drivers
hwmon: add NXP MC33978/MC34978 driver
mux: add NXP MC33978/MC34978 AMUX driver

.../bindings/pinctrl/nxp,mc33978.yaml | 158 +++
drivers/hwmon/Kconfig | 10 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/mc33978-hwmon.c | 548 ++++++++++
drivers/mfd/Kconfig | 15 +
drivers/mfd/Makefile | 2 +
drivers/mfd/mc33978.c | 988 ++++++++++++++++++
drivers/mux/Kconfig | 14 +
drivers/mux/Makefile | 2 +
drivers/mux/mc33978-mux.c | 136 +++
drivers/pinctrl/Kconfig | 14 +
drivers/pinctrl/Makefile | 1 +
drivers/pinctrl/core.c | 41 +-
drivers/pinctrl/pinconf.c | 9 +-
drivers/pinctrl/pinctrl-mc33978.c | 839 +++++++++++++++
include/linux/mfd/mc33978.h | 92 ++
16 files changed, 2863 insertions(+), 7 deletions(-)
create mode 100644 Documentation/devicetree/bindings/pinctrl/nxp,mc33978.yaml
create mode 100644 drivers/hwmon/mc33978-hwmon.c
create mode 100644 drivers/mfd/mc33978.c
create mode 100644 drivers/mux/mc33978-mux.c
create mode 100644 drivers/pinctrl/pinctrl-mc33978.c
create mode 100644 include/linux/mfd/mc33978.h

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2.47.3