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 v7: - pass checkpatch.pl --strict - using u32 replace uint32 - using devm_kzalloc(*) replace devm_kzalloc(sizeof()) - sort header files alphabetically - delete unnecessary header files - fix wrap error - drop dependent description - using hardware automatic calibration replace software calibration. see documentation 197 page v7: https://lore.kernel.org/all/20240122080500.2621-1-qiujingbao.dlmu@xxxxxxxxx/ documentation: https://github.com/milkv-duo/duo-files/blob/main/duo/datasheet/CV1800B-CV1801B-Preliminary-Datasheet-full-en.pdf Changes since v6: - completely delete POR dt node - remove syscon tag - use devm_regmap_init_mmio() replace syscon_node_to_regmap v6: https://lore.kernel.org/all/20240115160600.5444-1-qiujingbao.dlmu@xxxxxxxxx/ 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 (2): dt-bindings: rtc: sophgo: add RTC support for Sophgo CV1800 series SoC rtc: sophgo: add rtc support for Sophgo CV1800 SoC .../bindings/rtc/sophgo,cv1800-rtc.yaml | 53 ++++ drivers/rtc/Kconfig | 10 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-cv1800.c | 244 ++++++++++++++++++ 4 files changed, 308 insertions(+) create mode 100644 Documentation/devicetree/bindings/rtc/sophgo,cv1800-rtc.yaml create mode 100644 drivers/rtc/rtc-cv1800.c base-commit: 14688f1a91e1f37bc6bf50ff5241e857f24338e0 -- 2.25.1
