From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/rtc/rtc-rx8025.c | 592 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 592 insertions(+) create mode 100644 drivers/rtc/rtc-rx8025.c (limited to 'drivers/rtc/rtc-rx8025.c') diff --git a/drivers/rtc/rtc-rx8025.c b/drivers/rtc/rtc-rx8025.c new file mode 100644 index 0000000000..aabe62c283 --- /dev/null +++ b/drivers/rtc/rtc-rx8025.c @@ -0,0 +1,592 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for Epson's RTC module RX-8025 SA/NB + * + * Copyright (C) 2009 Wolfgang Grandegger + * + * Copyright (C) 2005 by Digi International Inc. + * All rights reserved. + * + * Modified by fengjh at rising.com.cn + * + * 2006.11 + * + * Code cleanup by Sergei Poselenov, + * Converted to new style by Wolfgang Grandegger + * Alarm and periodic interrupt added by Dmitry Rakhchev + */ +#include +#include +#include +#include +#include +#include +#include + +/* Register definitions */ +#define RX8025_REG_SEC 0x00 +#define RX8025_REG_MIN 0x01 +#define RX8025_REG_HOUR 0x02 +#define RX8025_REG_WDAY 0x03 +#define RX8025_REG_MDAY 0x04 +#define RX8025_REG_MONTH 0x05 +#define RX8025_REG_YEAR 0x06 +#define RX8025_REG_DIGOFF 0x07 +#define RX8025_REG_ALWMIN 0x08 +#define RX8025_REG_ALWHOUR 0x09 +#define RX8025_REG_ALWWDAY 0x0a +#define RX8025_REG_ALDMIN 0x0b +#define RX8025_REG_ALDHOUR 0x0c +/* 0x0d is reserved */ +#define RX8025_REG_CTRL1 0x0e +#define RX8025_REG_CTRL2 0x0f + +#define RX8025_BIT_CTRL1_CT (7 << 0) +/* 1 Hz periodic level irq */ +#define RX8025_BIT_CTRL1_CT_1HZ 4 +#define RX8025_BIT_CTRL1_TEST BIT(3) +#define RX8025_BIT_CTRL1_1224 BIT(5) +#define RX8025_BIT_CTRL1_DALE BIT(6) +#define RX8025_BIT_CTRL1_WALE BIT(7) + +#define RX8025_BIT_CTRL2_DAFG BIT(0) +#define RX8025_BIT_CTRL2_WAFG BIT(1) +#define RX8025_BIT_CTRL2_CTFG BIT(2) +#define RX8025_BIT_CTRL2_PON BIT(4) +#define RX8025_BIT_CTRL2_XST BIT(5) +#define RX8025_BIT_CTRL2_VDET BIT(6) + +#define RX8035_BIT_HOUR_1224 BIT(7) + +/* Clock precision adjustment */ +#define RX8025_ADJ_RESOLUTION 3050 /* in ppb */ +#define RX8025_ADJ_DATA_MAX 62 +#define RX8025_ADJ_DATA_MIN -62 + +enum rx_model { + model_rx_unknown, + model_rx_8025, + model_rx_8035, + model_last +}; + +static const struct i2c_device_id rx8025_id[] = { + { "rx8025", model_rx_8025 }, + { "rx8035", model_rx_8035 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, rx8025_id); + +struct rx8025_data { + struct rtc_device *rtc; + enum rx_model model; + u8 ctrl1; + int is_24; +}; + +static s32 rx8025_read_reg(const struct i2c_client *client, u8 number) +{ + return i2c_smbus_read_byte_data(client, number << 4); +} + +static int rx8025_read_regs(const struct i2c_client *client, + u8 number, u8 length, u8 *values) +{ + int ret = i2c_smbus_read_i2c_block_data(client, number << 4, length, + values); + if (ret != length) + return ret < 0 ? ret : -EIO; + + return 0; +} + +static s32 rx8025_write_reg(const struct i2c_client *client, u8 number, + u8 value) +{ + return i2c_smbus_write_byte_data(client, number << 4, value); +} + +static s32 rx8025_write_regs(const struct i2c_client *client, + u8 number, u8 length, const u8 *values) +{ + return i2c_smbus_write_i2c_block_data(client, number << 4, + length, values); +} + +static int rx8025_is_osc_stopped(enum rx_model model, int ctrl2) +{ + int xstp = ctrl2 & RX8025_BIT_CTRL2_XST; + /* XSTP bit has different polarity on RX-8025 vs RX-8035. + * RX-8025: 0 == oscillator stopped + * RX-8035: 1 == oscillator stopped + */ + + if (model == model_rx_8025) + xstp = !xstp; + + return xstp; +} + +static int rx8025_check_validity(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct rx8025_data *drvdata = dev_get_drvdata(dev); + int ctrl2; + int xstp; + + ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2); + if (ctrl2 < 0) + return ctrl2; + + if (ctrl2 & RX8025_BIT_CTRL2_VDET) + dev_warn(dev, "power voltage drop detected\n"); + + if (ctrl2 & RX8025_BIT_CTRL2_PON) { + dev_warn(dev, "power-on reset detected, date is invalid\n"); + return -EINVAL; + } + + xstp = rx8025_is_osc_stopped(drvdata->model, ctrl2); + if (xstp) { + dev_warn(dev, "crystal stopped, date is invalid\n"); + return -EINVAL; + } + + return 0; +} + +static int rx8025_reset_validity(struct i2c_client *client) +{ + struct rx8025_data *drvdata = i2c_get_clientdata(client); + int ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2); + + if (ctrl2 < 0) + return ctrl2; + + ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET); + + if (drvdata->model == model_rx_8025) + ctrl2 |= RX8025_BIT_CTRL2_XST; + else + ctrl2 &= ~(RX8025_BIT_CTRL2_XST); + + return rx8025_write_reg(client, RX8025_REG_CTRL2, + ctrl2); +} + +static irqreturn_t rx8025_handle_irq(int irq, void *dev_id) +{ + struct i2c_client *client = dev_id; + struct rx8025_data *rx8025 = i2c_get_clientdata(client); + int status, xstp; + + rtc_lock(rx8025->rtc); + status = rx8025_read_reg(client, RX8025_REG_CTRL2); + if (status < 0) + goto out; + + xstp = rx8025_is_osc_stopped(rx8025->model, status); + if (xstp) + dev_warn(&client->dev, "Oscillation stop was detected," + "you may have to readjust the clock\n"); + + if (status & RX8025_BIT_CTRL2_CTFG) { + /* periodic */ + status &= ~RX8025_BIT_CTRL2_CTFG; + rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF); + } + + if (status & RX8025_BIT_CTRL2_DAFG) { + /* alarm */ + status &= RX8025_BIT_CTRL2_DAFG; + if (rx8025_write_reg(client, RX8025_REG_CTRL1, + rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE)) + goto out; + rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF); + } + +out: + rtc_unlock(rx8025->rtc); + + return IRQ_HANDLED; +} + +static int rx8025_get_time(struct device *dev, struct rtc_time *dt) +{ + struct i2c_client *client = to_i2c_client(dev); + struct rx8025_data *rx8025 = dev_get_drvdata(dev); + u8 date[7]; + int err; + + err = rx8025_check_validity(dev); + if (err) + return err; + + err = rx8025_read_regs(client, RX8025_REG_SEC, 7, date); + if (err) + return err; + + dev_dbg(dev, "%s: read %7ph\n", __func__, date); + + dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f); + dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f); + if (rx8025->is_24) + dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f); + else + dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12 + + (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0); + + dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f); + dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1; + dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]) + 100; + + dev_dbg(dev, "%s: date %ptRr\n", __func__, dt); + + return 0; +} + +static int rx8025_set_time(struct device *dev, struct rtc_time *dt) +{ + struct i2c_client *client = to_i2c_client(dev); + struct rx8025_data *rx8025 = dev_get_drvdata(dev); + u8 date[7]; + int ret; + + /* + * Here the read-only bits are written as "0". I'm not sure if that + * is sound. + */ + date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec); + date[RX8025_REG_MIN] = bin2bcd(dt->tm_min); + if (rx8025->is_24) + date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour); + else + date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0) + | bin2bcd((dt->tm_hour + 11) % 12 + 1); + + date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday); + date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday); + date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1); + date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year - 100); + + dev_dbg(dev, "%s: write %7ph\n", __func__, date); + + ret = rx8025_write_regs(client, RX8025_REG_SEC, 7, date); + if (ret < 0) + return ret; + + return rx8025_reset_validity(client); +} + +static int rx8025_init_client(struct i2c_client *client) +{ + struct rx8025_data *rx8025 = i2c_get_clientdata(client); + u8 ctrl[2], ctrl2; + int need_clear = 0; + int hour_reg; + int err; + + err = rx8025_read_regs(client, RX8025_REG_CTRL1, 2, ctrl); + if (err) + goto out; + + /* Keep test bit zero ! */ + rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST; + + if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) { + dev_warn(&client->dev, "Alarm was detected\n"); + need_clear = 1; + } + + if (ctrl[1] & RX8025_BIT_CTRL2_CTFG) + need_clear = 1; + + if (need_clear) { + ctrl2 = ctrl[1]; + ctrl2 &= ~(RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG | + RX8025_BIT_CTRL2_DAFG); + + err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2); + } + + if (rx8025->model == model_rx_8035) { + /* In RX-8035, 12/24 flag is in the hour register */ + hour_reg = rx8025_read_reg(client, RX8025_REG_HOUR); + if (hour_reg < 0) + return hour_reg; + rx8025->is_24 = (hour_reg & RX8035_BIT_HOUR_1224); + } else { + rx8025->is_24 = (ctrl[1] & RX8025_BIT_CTRL1_1224); + } +out: + return err; +} + +/* Alarm support */ +static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t) +{ + struct i2c_client *client = to_i2c_client(dev); + struct rx8025_data *rx8025 = dev_get_drvdata(dev); + u8 ald[2]; + int ctrl2, err; + + err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald); + if (err) + return err; + + ctrl2 = rx8025_read_reg(client, RX8025_REG_CTRL2); + if (ctrl2 < 0) + return ctrl2; + + dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n", + __func__, ald[0], ald[1], ctrl2); + + /* Hardware alarms precision is 1 minute! */ + t->time.tm_sec = 0; + t->time.tm_min = bcd2bin(ald[0] & 0x7f); + if (rx8025->is_24) + t->time.tm_hour = bcd2bin(ald[1] & 0x3f); + else + t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12 + + (ald[1] & 0x20 ? 12 : 0); + + dev_dbg(dev, "%s: date: %ptRr\n", __func__, &t->time); + t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE); + t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled; + + return err; +} + +static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t) +{ + struct i2c_client *client = to_i2c_client(dev); + struct rx8025_data *rx8025 = dev_get_drvdata(dev); + u8 ald[2]; + int err; + + ald[0] = bin2bcd(t->time.tm_min); + if (rx8025->is_24) + ald[1] = bin2bcd(t->time.tm_hour); + else + ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0) + | bin2bcd((t->time.tm_hour + 11) % 12 + 1); + + dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]); + + if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) { + rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE; + err = rx8025_write_reg(client, RX8025_REG_CTRL1, + rx8025->ctrl1); + if (err) + return err; + } + err = rx8025_write_regs(client, RX8025_REG_ALDMIN, 2, ald); + if (err) + return err; + + if (t->enabled) { + rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE; + err = rx8025_write_reg(client, RX8025_REG_CTRL1, + rx8025->ctrl1); + if (err) + return err; + } + + return 0; +} + +static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct i2c_client *client = to_i2c_client(dev); + struct rx8025_data *rx8025 = dev_get_drvdata(dev); + u8 ctrl1; + int err; + + ctrl1 = rx8025->ctrl1; + if (enabled) + ctrl1 |= RX8025_BIT_CTRL1_DALE; + else + ctrl1 &= ~RX8025_BIT_CTRL1_DALE; + + if (ctrl1 != rx8025->ctrl1) { + rx8025->ctrl1 = ctrl1; + err = rx8025_write_reg(client, RX8025_REG_CTRL1, + rx8025->ctrl1); + if (err) + return err; + } + return 0; +} + +/* + * According to the RX8025 SA/NB application manual the frequency and + * temperature characteristics can be approximated using the following + * equation: + * + * df = a * (ut - t)**2 + * + * df: Frequency deviation in any temperature + * a : Coefficient = (-35 +-5) * 10**-9 + * ut: Ultimate temperature in degree = +25 +-5 degree + * t : Any temperature in degree + */ +static int rx8025_read_offset(struct device *dev, long *offset) +{ + struct i2c_client *client = to_i2c_client(dev); + int digoff; + + digoff = rx8025_read_reg(client, RX8025_REG_DIGOFF); + if (digoff < 0) + return digoff; + + *offset = digoff >= 64 ? digoff - 128 : digoff; + if (*offset > 0) + (*offset)--; + *offset *= RX8025_ADJ_RESOLUTION; + + return 0; +} + +static int rx8025_set_offset(struct device *dev, long offset) +{ + struct i2c_client *client = to_i2c_client(dev); + u8 digoff; + + offset /= RX8025_ADJ_RESOLUTION; + if (offset > RX8025_ADJ_DATA_MAX) + offset = RX8025_ADJ_DATA_MAX; + else if (offset < RX8025_ADJ_DATA_MIN) + offset = RX8025_ADJ_DATA_MIN; + else if (offset > 0) + offset++; + else if (offset < 0) + offset += 128; + digoff = offset; + + return rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff); +} + +static const struct rtc_class_ops rx8025_rtc_ops = { + .read_time = rx8025_get_time, + .set_time = rx8025_set_time, + .read_alarm = rx8025_read_alarm, + .set_alarm = rx8025_set_alarm, + .alarm_irq_enable = rx8025_alarm_irq_enable, + .read_offset = rx8025_read_offset, + .set_offset = rx8025_set_offset, +}; + +static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + long adj; + int err; + + dev_warn_once(dev, "clock_adjust_ppb is deprecated, use offset\n"); + err = rx8025_read_offset(dev, &adj); + if (err) + return err; + + return sprintf(buf, "%ld\n", -adj); +} + +static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + long adj; + int err; + + dev_warn_once(dev, "clock_adjust_ppb is deprecated, use offset\n"); + if (kstrtol(buf, 10, &adj) != 0) + return -EINVAL; + + err = rx8025_set_offset(dev, -adj); + + return err ? err : count; +} + +static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR, + rx8025_sysfs_show_clock_adjust, + rx8025_sysfs_store_clock_adjust); + +static struct attribute *rx8025_attrs[] = { + &dev_attr_clock_adjust_ppb.attr, + NULL +}; + +static const struct attribute_group rx8025_attr_group = { + .attrs = rx8025_attrs, +}; + +static int rx8025_probe(struct i2c_client *client) +{ + const struct i2c_device_id *id = i2c_match_id(rx8025_id, client); + struct i2c_adapter *adapter = client->adapter; + struct rx8025_data *rx8025; + int err = 0; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA + | I2C_FUNC_SMBUS_I2C_BLOCK)) { + dev_err(&adapter->dev, + "doesn't support required functionality\n"); + return -EIO; + } + + rx8025 = devm_kzalloc(&client->dev, sizeof(*rx8025), GFP_KERNEL); + if (!rx8025) + return -ENOMEM; + + i2c_set_clientdata(client, rx8025); + + if (id) + rx8025->model = id->driver_data; + + err = rx8025_init_client(client); + if (err) + return err; + + rx8025->rtc = devm_rtc_allocate_device(&client->dev); + if (IS_ERR(rx8025->rtc)) + return PTR_ERR(rx8025->rtc); + + rx8025->rtc->ops = &rx8025_rtc_ops; + rx8025->rtc->range_min = RTC_TIMESTAMP_BEGIN_1900; + rx8025->rtc->range_max = RTC_TIMESTAMP_END_2099; + + if (client->irq > 0) { + dev_info(&client->dev, "IRQ %d supplied\n", client->irq); + err = devm_request_threaded_irq(&client->dev, client->irq, NULL, + rx8025_handle_irq, + IRQF_ONESHOT, + "rx8025", client); + if (err) + clear_bit(RTC_FEATURE_ALARM, rx8025->rtc->features); + } + + rx8025->rtc->max_user_freq = 1; + + set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rx8025->rtc->features); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rx8025->rtc->features); + + err = rtc_add_group(rx8025->rtc, &rx8025_attr_group); + if (err) + return err; + + return devm_rtc_register_device(rx8025->rtc); +} + +static struct i2c_driver rx8025_driver = { + .driver = { + .name = "rtc-rx8025", + }, + .probe = rx8025_probe, + .id_table = rx8025_id, +}; + +module_i2c_driver(rx8025_driver); + +MODULE_AUTHOR("Wolfgang Grandegger "); +MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3