Hi Zhuxu Ran, On Sat, Oct 03, 2026 at 07:55:06PM +0800, Zhuxu Ran wrote: > Add a driver for the CV1800 RTC seconds counter described by the > upstream devicetree. Map the node's register range, enable the RTC > clock, and implement reading and setting the 32-bit counter. Bind > the existing sysreset driver as a child when enabled. > > Adapt the register definitions and seconds-counter sequence from > Linux drivers/rtc/rtc-cv1800.c by Jingbao Qiu. > > Link: https://git.kernel.org/linus/d9f82683b123ce315cc36c4b20a5bc3d8644f947 > > Signed-off-by: Zhuxu Ran <[email protected]>
Overall on this patch I think it is better to have consistent names: the driver file name is cv1800, but in other places like the config or the driver name you call it cv1800b. It is better to choose one and stick to it. > --- > drivers/rtc/Kconfig | 9 ++++ > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-cv1800.c | 123 > +++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 133 insertions(+) > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index 5b44cc99c97..547ac1643c9 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -54,6 +54,15 @@ config RTC_ARMADA38X > This adds support for the in-chip RTC that can be found in the > Armada 38x Marvell's SoC devices. > > +config RTC_CV1800B > + bool "Enable Sophgo CV1800B RTC driver" > + depends on DM_RTC > + select REGMAP > + help > + Enable access to the RTC seconds counter found on Sophgo CV1800 > + series SoCs. When system reset support is enabled, the driver also > + binds the reset function provided by the RTC subsystem. > + > config RTC_PCF2127 > bool "Enable PCF2127 driver" > depends on DM_RTC > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index 742481ce185..961fe5409f0 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -7,6 +7,7 @@ > obj-$(CONFIG_$(PHASE_)DM_RTC) += rtc-uclass.o > > obj-$(CONFIG_RTC_ARMADA38X) += armada38x.o > +obj-$(CONFIG_RTC_CV1800B) += rtc-cv1800.o > obj-$(CONFIG_RTC_DAVINCI) += davinci.o > obj-$(CONFIG_RTC_DS1307) += ds1307.o > obj-$(CONFIG_RTC_DS1337) += ds1337.o > diff --git a/drivers/rtc/rtc-cv1800.c b/drivers/rtc/rtc-cv1800.c > new file mode 100644 > index 00000000000..3a2b7b25748 > --- /dev/null > +++ b/drivers/rtc/rtc-cv1800.c > @@ -0,0 +1,123 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2026 Zhuxu Ran <[email protected]> > + * > + * Based on the Linux driver by Jingbao Qiu <[email protected]>. > + */ > + > +#include <clk.h> > +#include <dm.h> > +#include <dm/lists.h> > +#include <regmap.h> > +#include <rtc.h> > +#include <linux/bitops.h> > +#include <linux/errno.h> > +#include <linux/err.h> > + > +#define SEC_PULSE_GEN 0x1004 > +#define SET_SEC_CNTR_VAL 0x1010 > +#define SET_SEC_CNTR_TRIG 0x1014 > +#define SEC_CNTR_VAL 0x1018 > +#define MACRO_RG_SET_T 0x1498 > + > +#define SEL_SEC_PULSE BIT(31) > + > +struct cv1800_rtc_priv { > + struct regmap *regmap; > + struct clk clk; > +}; > + > +static int cv1800_rtc_get(struct udevice *dev, struct rtc_time *time) > +{ > + struct cv1800_rtc_priv *priv = dev_get_priv(dev); > + u32 value; > + int ret; > + > + ret = regmap_read(priv->regmap, SEC_PULSE_GEN, &value); > + if (ret) > + return ret; > + if (value & SEL_SEC_PULSE) > + return -EINVAL; > + > + ret = regmap_read(priv->regmap, SEC_CNTR_VAL, &value); > + if (ret) > + return ret; > + > + rtc_to_tm(value, time); > + > + return 0; > +} > + > +static int cv1800_rtc_set(struct udevice *dev, const struct rtc_time *time) > +{ > + struct cv1800_rtc_priv *priv = dev_get_priv(dev); > + time64_t seconds; > + int ret; > + > + if (time->tm_year < 1970) > + return -EINVAL; > + > + seconds = rtc_mktime(time); > + if (seconds < 0 || seconds > U32_MAX) > + return -ERANGE; > + > + ret = regmap_write(priv->regmap, SET_SEC_CNTR_VAL, seconds); > + if (ret) > + return ret; > + > + ret = regmap_write(priv->regmap, SET_SEC_CNTR_TRIG, 1); > + if (ret) > + return ret; > + > + ret = regmap_write(priv->regmap, MACRO_RG_SET_T, seconds); > + if (ret) > + return ret; > + > + return regmap_update_bits(priv->regmap, SEC_PULSE_GEN, > + SEL_SEC_PULSE, 0); > +} > + > +static int cv1800_rtc_bind(struct udevice *dev) > +{ > + if (!CONFIG_IS_ENABLED(SYSRESET_CV1800B)) > + return 0; > + > + return device_bind_driver_to_node(dev, "cv1800b_sysreset", > + "sysreset", dev_ofnode(dev), NULL); > +} > + > +static int cv1800_rtc_probe(struct udevice *dev) > +{ > + struct cv1800_rtc_priv *priv = dev_get_priv(dev); > + int ret; > + > + priv->regmap = devm_regmap_init(dev, NULL, NULL, NULL); > + if (IS_ERR(priv->regmap)) > + return PTR_ERR(priv->regmap); > + > + ret = clk_get_by_name(dev, "rtc", &priv->clk); > + if (ret) > + return ret; > + > + return clk_enable(&priv->clk); > +} > + > +static const struct rtc_ops cv1800_rtc_ops = { > + .get = cv1800_rtc_get, > + .set = cv1800_rtc_set, > +}; > + > +static const struct udevice_id cv1800_rtc_ids[] = { > + { .compatible = "sophgo,cv1800b-rtc" }, > + { } > +}; > + > +U_BOOT_DRIVER(cv1800b_rtc) = { > + .name = "cv1800b_rtc", > + .id = UCLASS_RTC, > + .of_match = cv1800_rtc_ids, > + .bind = cv1800_rtc_bind, > + .probe = cv1800_rtc_probe, > + .ops = &cv1800_rtc_ops, > + .priv_auto = sizeof(struct cv1800_rtc_priv), > +}; > > -- > 2.55.0 > Best regards, -- Hiago
