diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index cad667a404..aa6d90158c 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -166,4 +166,13 @@ config RTC_STM32 help Enable STM32 RTC driver. This driver supports the rtc that is present on some STM32 SoCs. + +config RTC_ABX80X + bool "Enable Abracon ABx80x RTC driver" + depends on DM_RTC + help + If you say yes here you get support for Abracon AB080X and AB180X + families of ultra-low-power battery- and capacitor-backed real-time + clock chips. + endmenu diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index ef66dc4bf0..6a45a9c874 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -55,3 +55,4 @@ obj-$(CONFIG_RTC_S35392A) += s35392a.o obj-$(CONFIG_RTC_STM32) += stm32_rtc.o obj-$(CONFIG_SANDBOX) += sandbox_rtc.o obj-$(CONFIG_RTC_X1205) += x1205.o +obj-$(CONFIG_RTC_ABX80X) += abx80x.o diff --git a/drivers/rtc/abx80x.c b/drivers/rtc/abx80x.c new file mode 100644 index 0000000000..528b06cbd6 --- /dev/null +++ b/drivers/rtc/abx80x.c @@ -0,0 +1,553 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A driver for the I2C members of the Abracon AB x8xx RTC family, + * and compatible: AB 1805 and AB 0805 + * + * Copyright 2014-2015 Macq S.A. + * Copyright 2020 Linaro + * + * Author: Philippe De Muyter + * Author: Alexandre Belloni + * Author: Ying-Chun Liu (PaulLiu) + * + */ + +#include +#include +#include +#include +#include + +#define ABX8XX_REG_HTH 0x00 +#define ABX8XX_REG_SC 0x01 +#define ABX8XX_REG_MN 0x02 +#define ABX8XX_REG_HR 0x03 +#define ABX8XX_REG_DA 0x04 +#define ABX8XX_REG_MO 0x05 +#define ABX8XX_REG_YR 0x06 +#define ABX8XX_REG_WD 0x07 + +#define ABX8XX_REG_AHTH 0x08 +#define ABX8XX_REG_ASC 0x09 +#define ABX8XX_REG_AMN 0x0a +#define ABX8XX_REG_AHR 0x0b +#define ABX8XX_REG_ADA 0x0c +#define ABX8XX_REG_AMO 0x0d +#define ABX8XX_REG_AWD 0x0e + +#define ABX8XX_REG_STATUS 0x0f +#define ABX8XX_STATUS_AF BIT(2) +#define ABX8XX_STATUS_BLF BIT(4) +#define ABX8XX_STATUS_WDT BIT(6) + +#define ABX8XX_REG_CTRL1 0x10 +#define ABX8XX_CTRL_WRITE BIT(0) +#define ABX8XX_CTRL_ARST BIT(2) +#define ABX8XX_CTRL_12_24 BIT(6) + +#define ABX8XX_REG_CTRL2 0x11 +#define ABX8XX_CTRL2_RSVD BIT(5) + +#define ABX8XX_REG_IRQ 0x12 +#define ABX8XX_IRQ_AIE BIT(2) +#define ABX8XX_IRQ_IM_1_4 (0x3 << 5) + +#define ABX8XX_REG_CD_TIMER_CTL 0x18 + +#define ABX8XX_REG_OSC 0x1c +#define ABX8XX_OSC_FOS BIT(3) +#define ABX8XX_OSC_BOS BIT(4) +#define ABX8XX_OSC_ACAL_512 BIT(5) +#define ABX8XX_OSC_ACAL_1024 BIT(6) + +#define ABX8XX_OSC_OSEL BIT(7) + +#define ABX8XX_REG_OSS 0x1d +#define ABX8XX_OSS_OF BIT(1) +#define ABX8XX_OSS_OMODE BIT(4) + +#define ABX8XX_REG_WDT 0x1b +#define ABX8XX_WDT_WDS BIT(7) +#define ABX8XX_WDT_BMB_MASK 0x7c +#define ABX8XX_WDT_BMB_SHIFT 2 +#define ABX8XX_WDT_MAX_TIME (ABX8XX_WDT_BMB_MASK >> ABX8XX_WDT_BMB_SHIFT) +#define ABX8XX_WDT_WRB_MASK 0x03 +#define ABX8XX_WDT_WRB_1HZ 0x02 + +#define ABX8XX_REG_CFG_KEY 0x1f +#define ABX8XX_CFG_KEY_OSC 0xa1 +#define ABX8XX_CFG_KEY_MISC 0x9d + +#define ABX8XX_REG_ID0 0x28 + +#define ABX8XX_REG_OUT_CTRL 0x30 +#define ABX8XX_OUT_CTRL_EXDS BIT(4) + +#define ABX8XX_REG_TRICKLE 0x20 +#define ABX8XX_TRICKLE_CHARGE_ENABLE 0xa0 +#define ABX8XX_TRICKLE_STANDARD_DIODE 0x8 +#define ABX8XX_TRICKLE_SCHOTTKY_DIODE 0x4 + +static u8 trickle_resistors[] = {0, 3, 6, 11}; + +enum abx80x_chip {AB0801, AB0803, AB0804, AB0805, + AB1801, AB1803, AB1804, AB1805, RV1805, ABX80X}; + +struct abx80x_cap { + u16 pn; + bool has_tc; + bool has_wdog; +}; + +static struct abx80x_cap abx80x_caps[] = { + [AB0801] = {.pn = 0x0801}, + [AB0803] = {.pn = 0x0803}, + [AB0804] = {.pn = 0x0804, .has_tc = true, .has_wdog = true}, + [AB0805] = {.pn = 0x0805, .has_tc = true, .has_wdog = true}, + [AB1801] = {.pn = 0x1801}, + [AB1803] = {.pn = 0x1803}, + [AB1804] = {.pn = 0x1804, .has_tc = true, .has_wdog = true}, + [AB1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true}, + [RV1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true}, + [ABX80X] = {.pn = 0} +}; + +static int abx80x_rtc_read8(struct udevice *dev, unsigned int reg) +{ + int ret = 0; + u8 buf; + + if (reg > 0xff) + return -EINVAL; + + ret = dm_i2c_read(dev, reg, &buf, sizeof(buf)); + if (ret < 0) + return ret; + + return buf; +} + +static int abx80x_rtc_write8(struct udevice *dev, unsigned int reg, int val) +{ + u8 buf = (u8)val; + + if (reg > 0xff) + return -EINVAL; + + return dm_i2c_write(dev, reg, &buf, sizeof(buf)); +} + +static int abx80x_is_rc_mode(struct udevice *dev) +{ + int flags = 0; + + flags = dm_i2c_reg_read(dev, ABX8XX_REG_OSS); + if (flags < 0) { + log_err("Failed to read autocalibration attribute\n"); + return flags; + } + + return (flags & ABX8XX_OSS_OMODE) ? 1 : 0; +} + +static int abx80x_enable_trickle_charger(struct udevice *dev, u8 trickle_cfg) +{ + int err; + + /* + * Write the configuration key register to enable access to the Trickle + * register + */ + err = dm_i2c_reg_write(dev, ABX8XX_REG_CFG_KEY, ABX8XX_CFG_KEY_MISC); + if (err < 0) { + log_err("Unable to write configuration key\n"); + return -EIO; + } + + err = dm_i2c_reg_write(dev, ABX8XX_REG_TRICKLE, + ABX8XX_TRICKLE_CHARGE_ENABLE | trickle_cfg); + if (err < 0) { + log_err("Unable to write trickle register\n"); + return -EIO; + } + + return 0; +} + +static int abx80x_rtc_read_time(struct udevice *dev, struct rtc_time *tm) +{ + unsigned char buf[8]; + int err, flags, rc_mode = 0; + + /* Read the Oscillator Failure only in XT mode */ + rc_mode = abx80x_is_rc_mode(dev); + if (rc_mode < 0) + return rc_mode; + + if (!rc_mode) { + flags = dm_i2c_reg_read(dev, ABX8XX_REG_OSS); + if (flags < 0) { + log_err("Unable to read oscillator status.\n"); + return flags; + } + + if (flags & ABX8XX_OSS_OF) + log_debug("Oscillator fail, data is not accurate.\n"); + } + + err = dm_i2c_read(dev, ABX8XX_REG_HTH, + buf, sizeof(buf)); + if (err < 0) { + log_err("Unable to read date\n"); + return -EIO; + } + + tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F); + tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F); + tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F); + tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7; + tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F); + tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F); + tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 2000; + + return 0; +} + +static int abx80x_rtc_set_time(struct udevice *dev, const struct rtc_time *tm) +{ + unsigned char buf[8]; + int err, flags; + + if (tm->tm_year < 2000) + return -EINVAL; + + buf[ABX8XX_REG_HTH] = 0; + buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec); + buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min); + buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour); + buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday); + buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon); + buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 2000); + buf[ABX8XX_REG_WD] = tm->tm_wday; + + err = dm_i2c_write(dev, ABX8XX_REG_HTH, + buf, sizeof(buf)); + if (err < 0) { + log_err("Unable to write to date registers\n"); + return -EIO; + } + + /* Clear the OF bit of Oscillator Status Register */ + flags = dm_i2c_reg_read(dev, ABX8XX_REG_OSS); + if (flags < 0) { + log_err("Unable to read oscillator status.\n"); + return flags; + } + + err = dm_i2c_reg_write(dev, ABX8XX_REG_OSS, + flags & ~ABX8XX_OSS_OF); + if (err < 0) { + log_err("Unable to write oscillator status register\n"); + return err; + } + + return 0; +} + +static int abx80x_rtc_set_autocalibration(struct udevice *dev, + int autocalibration) +{ + int retval, flags = 0; + + if (autocalibration != 0 && autocalibration != 1024 && + autocalibration != 512) { + log_err("autocalibration value outside permitted range\n"); + return -EINVAL; + } + + flags = dm_i2c_reg_read(dev, ABX8XX_REG_OSC); + if (flags < 0) + return flags; + + if (autocalibration == 0) { + flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024); + } else if (autocalibration == 1024) { + /* 1024 autocalibration is 0x10 */ + flags |= ABX8XX_OSC_ACAL_1024; + flags &= ~(ABX8XX_OSC_ACAL_512); + } else { + /* 512 autocalibration is 0x11 */ + flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512); + } + + /* Unlock write access to Oscillator Control Register */ + retval = dm_i2c_reg_write(dev, ABX8XX_REG_CFG_KEY, + ABX8XX_CFG_KEY_OSC); + if (retval < 0) { + log_err("Failed to write CONFIG_KEY register\n"); + return retval; + } + + retval = dm_i2c_reg_write(dev, ABX8XX_REG_OSC, flags); + + return retval; +} + +static int abx80x_rtc_get_autocalibration(struct udevice *dev) +{ + int flags = 0, autocalibration; + + flags = dm_i2c_reg_read(dev, ABX8XX_REG_OSC); + if (flags < 0) + return flags; + + if (flags & ABX8XX_OSC_ACAL_512) + autocalibration = 512; + else if (flags & ABX8XX_OSC_ACAL_1024) + autocalibration = 1024; + else + autocalibration = 0; + + return autocalibration; +} + +static struct rtc_time default_tm = { 0, 0, 0, 1, 1, 2000, 6, 0, 0 }; + +static int abx80x_rtc_reset(struct udevice *dev) +{ + int ret = 0; + + int autocalib = abx80x_rtc_get_autocalibration(dev); + + if (autocalib != 0) + abx80x_rtc_set_autocalibration(dev, 0); + + ret = abx80x_rtc_set_time(dev, &default_tm); + if (ret != 0) { + log_err("cannot set time to default_tm. error %d\n", ret); + return ret; + } + + return ret; +} + +static const struct rtc_ops abx80x_rtc_ops = { + .get = abx80x_rtc_read_time, + .set = abx80x_rtc_set_time, + .reset = abx80x_rtc_reset, + .read8 = abx80x_rtc_read8, + .write8 = abx80x_rtc_write8 +}; + +static int abx80x_dt_trickle_cfg(struct udevice *dev) +{ + const char *diode; + int trickle_cfg = 0; + int i, ret = 0; + u32 tmp; + + diode = ofnode_read_string(dev_ofnode(dev), "abracon,tc-diode"); + if (!diode) + return ret; + + if (!strcmp(diode, "standard")) { + trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE; + } else if (!strcmp(diode, "schottky")) { + trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE; + } else { + log_err("Invalid tc-diode value: %s\n", diode); + return -EINVAL; + } + + ret = ofnode_read_u32(dev_ofnode(dev), "abracon,tc-resistor", &tmp); + if (ret) + return ret; + + for (i = 0; i < sizeof(trickle_resistors); i++) + if (trickle_resistors[i] == tmp) + break; + + if (i == sizeof(trickle_resistors)) { + log_err("Invalid tc-resistor value: %u\n", tmp); + return -EINVAL; + } + + return (trickle_cfg | i); +} + +static int abx80x_probe(struct udevice *dev) +{ + int i, data, err, trickle_cfg = -EINVAL; + unsigned char buf[7]; + unsigned int part = dev->driver_data; + unsigned int partnumber; + unsigned int majrev, minrev; + unsigned int lot; + unsigned int wafer; + unsigned int uid; + + err = dm_i2c_read(dev, ABX8XX_REG_ID0, buf, sizeof(buf)); + if (err < 0) { + log_err("Unable to read partnumber\n"); + return -EIO; + } + + partnumber = (buf[0] << 8) | buf[1]; + majrev = buf[2] >> 3; + minrev = buf[2] & 0x7; + lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3]; + uid = ((buf[4] & 0x7f) << 8) | buf[5]; + wafer = (buf[6] & 0x7c) >> 2; + log_debug("model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n", + partnumber, majrev, minrev, lot, wafer, uid); + + data = dm_i2c_reg_read(dev, ABX8XX_REG_CTRL1); + if (data < 0) { + log_err("Unable to read control register\n"); + return -EIO; + } + + err = dm_i2c_reg_write(dev, ABX8XX_REG_CTRL1, + ((data & ~(ABX8XX_CTRL_12_24 | + ABX8XX_CTRL_ARST)) | + ABX8XX_CTRL_WRITE)); + if (err < 0) { + log_err("Unable to write control register\n"); + return -EIO; + } + + /* Configure RV1805 specifics */ + if (part == RV1805) { + /* + * Avoid accidentally entering test mode. This can happen + * on the RV1805 in case the reserved bit 5 in control2 + * register is set. RV-1805-C3 datasheet indicates that + * the bit should be cleared in section 11h - Control2. + */ + data = dm_i2c_reg_read(dev, ABX8XX_REG_CTRL2); + if (data < 0) { + log_err("Unable to read control2 register\n"); + return -EIO; + } + + err = dm_i2c_reg_write(dev, ABX8XX_REG_CTRL2, + data & ~ABX8XX_CTRL2_RSVD); + if (err < 0) { + log_err("Unable to write control2 register\n"); + return -EIO; + } + + /* + * Avoid extra power leakage. The RV1805 uses smaller + * 10pin package and the EXTI input is not present. + * Disable it to avoid leakage. + */ + data = dm_i2c_reg_read(dev, ABX8XX_REG_OUT_CTRL); + if (data < 0) { + log_err("Unable to read output control register\n"); + return -EIO; + } + + /* + * Write the configuration key register to enable access to + * the config2 register + */ + err = dm_i2c_reg_write(dev, ABX8XX_REG_CFG_KEY, + ABX8XX_CFG_KEY_MISC); + if (err < 0) { + log_err("Unable to write configuration key\n"); + return -EIO; + } + + err = dm_i2c_reg_write(dev, ABX8XX_REG_OUT_CTRL, + data | ABX8XX_OUT_CTRL_EXDS); + if (err < 0) { + log_err("Unable to write output control register\n"); + return -EIO; + } + } + + /* part autodetection */ + if (part == ABX80X) { + for (i = 0; abx80x_caps[i].pn; i++) + if (partnumber == abx80x_caps[i].pn) + break; + if (abx80x_caps[i].pn == 0) { + log_err("Unknown part: %04x\n", partnumber); + return -EINVAL; + } + part = i; + } + + if (partnumber != abx80x_caps[part].pn) { + log_err("partnumber mismatch %04x != %04x\n", + partnumber, abx80x_caps[part].pn); + return -EINVAL; + } + + if (abx80x_caps[part].has_tc) + trickle_cfg = abx80x_dt_trickle_cfg(dev); + + if (trickle_cfg > 0) { + log_debug("Enabling trickle charger: %02x\n", trickle_cfg); + abx80x_enable_trickle_charger(dev, trickle_cfg); + } + + err = dm_i2c_reg_write(dev, ABX8XX_REG_CD_TIMER_CTL, BIT(2)); + if (err) + return err; + + return 0; +} + +static const struct udevice_id abx80x_of_match[] = { + { + .compatible = "abracon,abx80x", + .data = ABX80X + }, + { + .compatible = "abracon,ab0801", + .data = AB0801 + }, + { + .compatible = "abracon,ab0803", + .data = AB0803 + }, + { + .compatible = "abracon,ab0804", + .data = AB0804 + }, + { + .compatible = "abracon,ab0805", + .data = AB0805 + }, + { + .compatible = "abracon,ab1801", + .data = AB1801 + }, + { + .compatible = "abracon,ab1803", + .data = AB1803 + }, + { + .compatible = "abracon,ab1804", + .data = AB1804 + }, + { + .compatible = "abracon,ab1805", + .data = AB1805 + }, + { + .compatible = "microcrystal,rv1805", + .data = RV1805 + }, + { } +}; + +U_BOOT_DRIVER(abx80x_rtc) = { + .name = "rtc-abx80x", + .id = UCLASS_RTC, + .probe = abx80x_probe, + .of_match = abx80x_of_match, + .ops = &abx80x_rtc_ops, +};