[PATCH v10 0/3] Add RP1 PWM controller support

[Andrea della Porta]

This patchset adds support for the PWM controller found on the
Raspberry Pi RP1 southbridge. This is necessary to operate the
cooling fan connected to one of the PWM channels.

The tachometer pin for the fan speed is managed by the firmware 
running on the RP1's M-core. It uses the PHASE2 register
to report the RPM, which will be exported by this driver via
a function. A subsequent patch will add the function to read the
speed to this driver and a new device and driver to read the RPM
and export this value via hwmon.
 
Subsequent patches will also add the CPU thermal zone, which
acts as a consumer of the PWM device.

Best regards,
Andrea


CHANGES in V10:

- regmap reworked in favor of writel/readl, since no syscon is needed
  anymore.
- removed the read_tachometer function, it will be reintroduced again
  if a future patchset dealing also with the consumer driver. As a
  result, get rid of the common header file with the function prototype.
- dropped the mutex and locking mechanism since it's no longer needed.
- Makefile: removed dependency from REGMAP_MMIO

Link to V9:
https://lore.kernel.org/all/cover.1789724999.git.andrea.porta@suse.com/


Naushir Patuck (2):
  dt-bindings: pwm: Add Raspberry Pi RP1 PWM controller
  pwm: rp1: Add RP1 PWM controller driver

Stanimir Varbanov (1):
  arm64: dts: broadcom: rpi-5: Add RP1 PWM node

 .../bindings/pwm/raspberrypi,rp1-pwm.yaml     |  66 +++
 .../boot/dts/broadcom/bcm2712-rpi-5-b.dts     |  12 +
 arch/arm64/boot/dts/broadcom/rp1-common.dtsi  |   9 +
 drivers/pwm/Kconfig                           |   7 +
 drivers/pwm/Makefile                          |   1 +
 drivers/pwm/pwm-rp1.c                         | 417 ++++++++++++++++++
 6 files changed, 512 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pwm/raspberrypi,rp1-pwm.yaml
 create mode 100644 drivers/pwm/pwm-rp1.c

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2.35.3