input: Introduce support for SPMI haptics found on Qcom PMICs

This series introduces a driver for the SPMI haptics hardware block found in Qualcomm PMICs. SPMI haptics support LRA (Linear Resonant Actuator) style haptics, as well as ERM (Eccentric Rotating Mass). It also supports several modes of driving the haptics, e.g. by loading the pattern to play into an internal buffer, or using PWM.

More information about the hardware can be found here:

        https://gitlab.com/sdm845-mainline/linux/-/wikis/PMI8998-QPNP-Haptics

This driver has been written based on downstream sources as no public documentation is available. It includes initial support for LRA haptics in buffer mode, this combination seems to be the most common and will enable haptics on the OnePlus 6 and 6T, PocoPhone F1, OnePlus 5 and several other Qualcomm devices with mainline kernel support.

The driver is implemented using the ff-memless (forcefeedback) input framework and makes an attempt to control the strength of vibration relative to the magnitude set from userspace.

~ Caleb

Changes since v1:
- Replace old QPNP naming with SPMI
- Address Bjorn's comments on the driver, various style and code cleanups
- Address Bjorn's comments on the DT bindings and DTS
- Pickup patches from Joel and Jami to enable haptics on the OnePlus 5 and Poco F1.

Caleb Connolly (4):
dt-bindings: input: add Qualcomm SPMI haptics driver
input: add Qualcomm SPMI haptics driver
arm64: dts: qcom: pmi8998: introduce spmi haptics
arm64: dts: qcom: sdm845-oneplus-common: add haptics

Jami Kettunen (1):
arm64: dts: qcom: msm8998-oneplus-common: Enable PMI8998 haptics

Joel Selvaraj (1):
arm64: dts: qcom: sdm845-xiaomi-beryllium: add haptics

 .../bindings/input/qcom,spmi-haptics.yaml          | 128 +++
 .../boot/dts/qcom/msm8998-oneplus-common.dtsi      |   6 +
 arch/arm64/boot/dts/qcom/pmi8998.dtsi              |  16 +
 .../arm64/boot/dts/qcom/sdm845-oneplus-common.dtsi |   6 +
 .../boot/dts/qcom/sdm845-xiaomi-beryllium.dts      |   5 +
 drivers/input/misc/Kconfig                         |  12 +
 drivers/input/misc/Makefile                        |   1 +
 drivers/input/misc/qcom-spmi-haptics.c             | 980 +++++++++++++++++++++
 include/dt-bindings/input/qcom,spmi-haptics.h      |  32 +
 9 files changed, 1186 insertions(+)