diff options
Diffstat (limited to 'drivers/rtc/rv8803.c')
| -rw-r--r-- | drivers/rtc/rv8803.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/drivers/rtc/rv8803.c b/drivers/rtc/rv8803.c new file mode 100644 index 0000000000..2ab40f0833 --- /dev/null +++ b/drivers/rtc/rv8803.c @@ -0,0 +1,167 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Date & Time support for Micro Crystal RV-8803-C7. + * + * based on ds1307.c which is + * (C) Copyright 2001, 2002, 2003 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * Keith Outwater, keith_outwater@mvis.com` + * Steven Scholz, steven.scholz@imc-berlin.de + * + */ + +#include <common.h> +#include <command.h> +#include <dm.h> +#include <rtc.h> +#include <i2c.h> + +/* + * RTC register addresses + */ +#define RTC_SEC_REG_ADDR 0x00 +#define RTC_MIN_REG_ADDR 0x01 +#define RTC_HR_REG_ADDR 0x02 +#define RTC_DAY_REG_ADDR 0x03 +#define RTC_DATE_REG_ADDR 0x04 +#define RTC_MON_REG_ADDR 0x05 +#define RTC_YR_REG_ADDR 0x06 + +#define RTC_FLAG_REG_ADDR 0x0E +#define RTC_FLAG_BIT_V1F BIT(0) +#define RTC_FLAG_BIT_V2F BIT(1) + +#define RTC_CTL_REG_ADDR 0x0F +#define RTC_CTL_BIT_RST BIT(0) + +static int rv8803_rtc_set(struct udevice *dev, const struct rtc_time *tm) +{ + int ret; + u8 buf[7]; + + debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday, + tm->tm_hour, tm->tm_min, tm->tm_sec); + + if (tm->tm_year < 2000 || tm->tm_year > 2099) + printf("WARNING: year should be between 2000 and 2099!\n"); + + buf[RTC_YR_REG_ADDR] = bin2bcd(tm->tm_year % 100); + buf[RTC_MON_REG_ADDR] = bin2bcd(tm->tm_mon); + buf[RTC_DAY_REG_ADDR] = 1 << (tm->tm_wday & 0x7); + buf[RTC_DATE_REG_ADDR] = bin2bcd(tm->tm_mday); + buf[RTC_HR_REG_ADDR] = bin2bcd(tm->tm_hour); + buf[RTC_MIN_REG_ADDR] = bin2bcd(tm->tm_min); + buf[RTC_SEC_REG_ADDR] = bin2bcd(tm->tm_sec); + + ret = dm_i2c_write(dev, 0, buf, sizeof(buf)); + if (ret < 0) + return ret; + + return 0; +} + +static int rv8803_rtc_get(struct udevice *dev, struct rtc_time *tm) +{ + int ret; + u8 buf[7]; + int flags; + + flags = dm_i2c_reg_read(dev, RTC_FLAG_REG_ADDR); + if (flags < 0) + return flags; + debug("%s: flags=%Xh\n", __func__, flags); + + if (flags & RTC_FLAG_BIT_V1F) + printf("### Warning: temperature compensation has stopped\n"); + + if (flags & RTC_FLAG_BIT_V2F) { + printf("### Warning: Voltage low, data is invalid\n"); + return -1; + } + + ret = dm_i2c_read(dev, 0, buf, sizeof(buf)); + if (ret < 0) + return ret; + + tm->tm_sec = bcd2bin(buf[RTC_SEC_REG_ADDR] & 0x7F); + tm->tm_min = bcd2bin(buf[RTC_MIN_REG_ADDR] & 0x7F); + tm->tm_hour = bcd2bin(buf[RTC_HR_REG_ADDR] & 0x3F); + tm->tm_mday = bcd2bin(buf[RTC_DATE_REG_ADDR] & 0x3F); + tm->tm_mon = bcd2bin(buf[RTC_MON_REG_ADDR] & 0x1F); + tm->tm_year = bcd2bin(buf[RTC_YR_REG_ADDR]) + 2000; + tm->tm_wday = fls(buf[RTC_DAY_REG_ADDR] & 0x7F) - 1; + tm->tm_yday = 0; + tm->tm_isdst = 0; + + debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday, + tm->tm_hour, tm->tm_min, tm->tm_sec); + + return 0; +} + +static int rv8803_rtc_reset(struct udevice *dev) +{ + int ret; + struct rtc_time tmp = { + .tm_year = 2000, + .tm_mon = 1, + .tm_mday = 1, + .tm_hour = 0, + .tm_min = 0, + .tm_sec = 0, + }; + + /* assert reset */ + ret = dm_i2c_reg_write(dev, RTC_CTL_REG_ADDR, RTC_CTL_BIT_RST); + if (ret < 0) + return ret; + + /* clear all flags */ + ret = dm_i2c_reg_write(dev, RTC_FLAG_REG_ADDR, 0); + if (ret < 0) + return ret; + + ret = rv8803_rtc_set(dev, &tmp); + if (ret < 0) + return ret; + + /* clear reset */ + ret = dm_i2c_reg_write(dev, RTC_CTL_REG_ADDR, 0); + if (ret < 0) + return ret; + + debug("RTC: %4d-%02d-%02d %2d:%02d:%02d UTC\n", + tmp.tm_year, tmp.tm_mon, tmp.tm_mday, + tmp.tm_hour, tmp.tm_min, tmp.tm_sec); + + return 0; +} + +static int rv8803_probe(struct udevice *dev) +{ + i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS | + DM_I2C_CHIP_WR_ADDRESS); + + return 0; +} + +static const struct rtc_ops rv8803_rtc_ops = { + .get = rv8803_rtc_get, + .set = rv8803_rtc_set, + .reset = rv8803_rtc_reset, +}; + +static const struct udevice_id rv8803_rtc_ids[] = { + { .compatible = "microcrystal,rv8803", }, + { } +}; + +U_BOOT_DRIVER(rtc_rv8803) = { + .name = "rtc-rv8803", + .id = UCLASS_RTC, + .probe = rv8803_probe, + .of_match = rv8803_rtc_ids, + .ops = &rv8803_rtc_ops, +}; |