[PATCH v6 0/3] riscv: rtc: sophgo: add mfd and rtc support for CV1800

[Jingbao Qiu]

Real Time Clock (RTC) is an independently powered module
within the chip, which includes a 32KHz oscillator and
a Power On Reset/POR submodule. It can be used for time
display and timed alarm generation.

Power On Reset/POR submodule only using register resources
so it should be empty. The 32KHz oscillator only provides
pulses for RTC in hardware.

Changes since v5:
- remove unnecessary lock
- fix cv1800_rtc_alarm_irq_enable()
- remove duplicate checks
- using alrm->enabled instead of unconditionally
  enabling
- remove disable alarms on probe
- using rtc_update_irq() replace mess of alarm
- remove leak clk
- useing devm_rtc_allocate_device() and
  devm_rtc_register_device() instead old way
- add judgment for rtc_enable_sec_counter()
- add POR nodes in DTS. This POR device shares
  the register region with the RTC device

v5: https://lore.kernel.org/all/20240108072253.30183-1-qiujingbao.dlmu@xxxxxxxxx/

Changes since v4:
- remove POR dt-bindings because it empty
- remove MFD dt-bindings because SoC does
  not have MFDs
- add syscon attribute to share registers
  with POR

v4: https://lore.kernel.org/all/20231229090643.116575-1-qiujingbao.dlmu@xxxxxxxxx/

Changes since v3:
- temporarily not submitting RTC driver code
  waiting for communication with IC designer
- add MFD dt-bindings
- add POR dt-bindings

v3: https://lore.kernel.org/all/20231226100431.331616-1-qiujingbao.dlmu@xxxxxxxxx/

Changes since v2:
- add mfd support for CV1800
- add rtc to mfd
- using regmap replace iomap
- merge register address in dts

v2: https://lore.kernel.org/lkml/20231217110952.78784-1-qiujingbao.dlmu@xxxxxxxxx/

Changes since v1
- fix duplicate names in subject
- using RTC replace RTC controller
- improve the properties of dt-bindings
- using `unevaluatedProperties` replace `additionalProperties`
- dt-bindings passed the test
- using `devm_platform_ioremap_resource()` replace
  `platform_get_resource()` and `devm_ioremap_resource()`
- fix random order of the code
- fix wrong wrapping of the `devm_request_irq()` and map the flag with dts
- using devm_clk_get_enabled replace `devm_clk_get()` and
  `clk_prepare_enable()`
- fix return style
- add rtc clock calibration function
- use spinlock when write register on read/set time

v1: https://lore.kernel.org/lkml/20231121094642.2973795-1-qiujingbao.dlmu@xxxxxxxxx/

Jingbao Qiu (3):
  dt-bindings: rtc: sophgo: add RTC support for Sophgo CV1800 series SoC
  rtc: sophgo: add rtc support for Sophgo CV1800 SoC
  riscv: dts: sophgo: add rtc dt node for CV1800

 .../bindings/rtc/sophgo,cv1800-rtc.yaml       |  55 +++
 arch/riscv/boot/dts/sophgo/cv1800b.dtsi       |  12 +
 drivers/rtc/Kconfig                           |   7 +
 drivers/rtc/Makefile                          |   1 +
 drivers/rtc/rtc-cv1800.c                      | 397 ++++++++++++++++++
 5 files changed, 472 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/rtc/sophgo,cv1800-rtc.yaml
 create mode 100644 drivers/rtc/rtc-cv1800.c


base-commit: e3d3fe7e7bf08820a83c9d9a4c38c7b29a2927f1
-- 
2.43.0