blob: 823aff03f5f02a86c43d4d25817271b3217c6ac7 [file] [log] [blame]
// 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 <phdm@macqel.be>
* Author: Alexandre Belloni <alexandre.belloni@bootlin.com>
* Author: Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>
*
*/
#include <common.h>
#include <dm.h>
#include <i2c.h>
#include <rtc.h>
#include <log.h>
#include <linux/bitfield.h>
#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
#define ABX8XX_REG_EXTRAM 0x3f
#define ABX8XX_EXTRAM_XADS GENMASK(1, 0)
#define ABX8XX_SRAM_BASE 0x40
#define ABX8XX_SRAM_WIN_SIZE 0x40U
#define ABX8XX_RAM_SIZE 256
#define RAM_ADDR_LOWER GENMASK(5, 0)
#define RAM_ADDR_UPPER GENMASK(7, 6)
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_xfer(struct udevice *dev, unsigned int offset,
u8 *val, unsigned int bytes, bool write)
{
int ret;
if (offset + bytes > ABX8XX_RAM_SIZE)
return -EINVAL;
while (bytes) {
u8 extram, reg, len, lower, upper;
lower = FIELD_GET(RAM_ADDR_LOWER, offset);
upper = FIELD_GET(RAM_ADDR_UPPER, offset);
extram = FIELD_PREP(ABX8XX_EXTRAM_XADS, upper);
reg = ABX8XX_SRAM_BASE + lower;
len = min(lower + bytes, ABX8XX_SRAM_WIN_SIZE) - lower;
ret = dm_i2c_reg_write(dev, ABX8XX_REG_EXTRAM, extram);
if (ret)
return ret;
if (write)
ret = dm_i2c_write(dev, reg, val, len);
else
ret = dm_i2c_read(dev, reg, val, len);
if (ret)
return ret;
offset += len;
val += len;
bytes -= len;
}
return 0;
}
static int abx80x_rtc_read(struct udevice *dev, unsigned int offset, u8 *val,
unsigned int bytes)
{
return abx80x_rtc_xfer(dev, offset, val, bytes, false);
}
static int abx80x_rtc_write(struct udevice *dev, unsigned int offset,
const u8 *val, unsigned int bytes)
{
return abx80x_rtc_xfer(dev, offset, (u8 *)val, bytes, true);
}
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,
.read = abx80x_rtc_read,
.write = abx80x_rtc_write,
};
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,
};