// SPDX-License-Identifier: GPL-2.0-only /* * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips. * * Copyright (C) 2005 James Chapman (ds1337 core) * Copyright (C) 2006 David Brownell * Copyright (C) 2009 Matthias Fuchs (rx8025 support) * Copyright (C) 2012 Bertrand Achard (nvram access fixes) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * We can't determine type by probing, but if we expect pre-Linux code * to have set the chip up as a clock (turning on the oscillator and * setting the date and time), Linux can ignore the non-clock features. * That's a natural job for a factory or repair bench. */ enum ds_type { unknown_ds_type, /* always first and 0 */ ds_1307, ds_1308, ds_1337, ds_1338, ds_1339, ds_1340, ds_1341, ds_1388, ds_3231, m41t0, m41t00, m41t11, mcp794xx, rx_8025, rx_8130, last_ds_type /* always last */ /* rs5c372 too? different address... */ }; /* RTC registers don't differ much, except for the century flag */ #define DS1307_REG_SECS 0x00 /* 00-59 */ # define DS1307_BIT_CH 0x80 # define DS1340_BIT_nEOSC 0x80 # define MCP794XX_BIT_ST 0x80 #define DS1307_REG_MIN 0x01 /* 00-59 */ # define M41T0_BIT_OF 0x80 #define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */ # define DS1307_BIT_12HR 0x40 /* in REG_HOUR */ # define DS1307_BIT_PM 0x20 /* in REG_HOUR */ # define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */ # define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */ #define DS1307_REG_WDAY 0x03 /* 01-07 */ # define MCP794XX_BIT_VBATEN 0x08 #define DS1307_REG_MDAY 0x04 /* 01-31 */ #define DS1307_REG_MONTH 0x05 /* 01-12 */ # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */ #define DS1307_REG_YEAR 0x06 /* 00-99 */ /* * Other registers (control, status, alarms, trickle charge, NVRAM, etc) * start at 7, and they differ a LOT. Only control and status matter for * basic RTC date and time functionality; be careful using them. */ #define DS1307_REG_CONTROL 0x07 /* or ds1338 */ # define DS1307_BIT_OUT 0x80 # define DS1338_BIT_OSF 0x20 # define DS1307_BIT_SQWE 0x10 # define DS1307_BIT_RS1 0x02 # define DS1307_BIT_RS0 0x01 #define DS1337_REG_CONTROL 0x0e # define DS1337_BIT_nEOSC 0x80 # define DS1339_BIT_BBSQI 0x20 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */ # define DS1337_BIT_RS2 0x10 # define DS1337_BIT_RS1 0x08 # define DS1337_BIT_INTCN 0x04 # define DS1337_BIT_A2IE 0x02 # define DS1337_BIT_A1IE 0x01 #define DS1340_REG_CONTROL 0x07 # define DS1340_BIT_OUT 0x80 # define DS1340_BIT_FT 0x40 # define DS1340_BIT_CALIB_SIGN 0x20 # define DS1340_M_CALIBRATION 0x1f #define DS1340_REG_FLAG 0x09 # define DS1340_BIT_OSF 0x80 #define DS1337_REG_STATUS 0x0f # define DS1337_BIT_OSF 0x80 # define DS3231_BIT_EN32KHZ 0x08 # define DS1337_BIT_A2I 0x02 # define DS1337_BIT_A1I 0x01 #define DS1339_REG_ALARM1_SECS 0x07 #define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0 #define RX8025_REG_CTRL1 0x0e # define RX8025_BIT_2412 0x20 #define RX8025_REG_CTRL2 0x0f # define RX8025_BIT_PON 0x10 # define RX8025_BIT_VDET 0x40 # define RX8025_BIT_XST 0x20 #define RX8130_REG_ALARM_MIN 0x17 #define RX8130_REG_ALARM_HOUR 0x18 #define RX8130_REG_ALARM_WEEK_OR_DAY 0x19 #define RX8130_REG_EXTENSION 0x1c #define RX8130_REG_EXTENSION_WADA BIT(3) #define RX8130_REG_FLAG 0x1d #define RX8130_REG_FLAG_VLF BIT(1) #define RX8130_REG_FLAG_AF BIT(3) #define RX8130_REG_CONTROL0 0x1e #define RX8130_REG_CONTROL0_AIE BIT(3) #define RX8130_REG_CONTROL1 0x1f #define RX8130_REG_CONTROL1_INIEN BIT(4) #define RX8130_REG_CONTROL1_CHGEN BIT(5) #define MCP794XX_REG_CONTROL 0x07 # define MCP794XX_BIT_ALM0_EN 0x10 # define MCP794XX_BIT_ALM1_EN 0x20 #define MCP794XX_REG_ALARM0_BASE 0x0a #define MCP794XX_REG_ALARM0_CTRL 0x0d #define MCP794XX_REG_ALARM1_BASE 0x11 #define MCP794XX_REG_ALARM1_CTRL 0x14 # define MCP794XX_BIT_ALMX_IF BIT(3) # define MCP794XX_BIT_ALMX_C0 BIT(4) # define MCP794XX_BIT_ALMX_C1 BIT(5) # define MCP794XX_BIT_ALMX_C2 BIT(6) # define MCP794XX_BIT_ALMX_POL BIT(7) # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \ MCP794XX_BIT_ALMX_C1 | \ MCP794XX_BIT_ALMX_C2) #define M41TXX_REG_CONTROL 0x07 # define M41TXX_BIT_OUT BIT(7) # define M41TXX_BIT_FT BIT(6) # define M41TXX_BIT_CALIB_SIGN BIT(5) # define M41TXX_M_CALIBRATION GENMASK(4, 0) #define DS1388_REG_WDOG_HUN_SECS 0x08 #define DS1388_REG_WDOG_SECS 0x09 #define DS1388_REG_FLAG 0x0b # define DS1388_BIT_WF BIT(6) # define DS1388_BIT_OSF BIT(7) #define DS1388_REG_CONTROL 0x0c # define DS1388_BIT_RST BIT(0) # define DS1388_BIT_WDE BIT(1) # define DS1388_BIT_nEOSC BIT(7) /* negative offset step is -2.034ppm */ #define M41TXX_NEG_OFFSET_STEP_PPB 2034 /* positive offset step is +4.068ppm */ #define M41TXX_POS_OFFSET_STEP_PPB 4068 /* Min and max values supported with 'offset' interface by M41TXX */ #define M41TXX_MIN_OFFSET ((-31) * M41TXX_NEG_OFFSET_STEP_PPB) #define M41TXX_MAX_OFFSET ((31) * M41TXX_POS_OFFSET_STEP_PPB) struct ds1307 { enum ds_type type; struct device *dev; struct regmap *regmap; const char *name; struct rtc_device *rtc; #ifdef CONFIG_COMMON_CLK struct clk_hw clks[2]; #endif }; struct chip_desc { unsigned alarm:1; u16 nvram_offset; u16 nvram_size; u8 offset; /* register's offset */ u8 century_reg; u8 century_enable_bit; u8 century_bit; u8 bbsqi_bit; irq_handler_t irq_handler; const struct rtc_class_ops *rtc_ops; u16 trickle_charger_reg; u8 (*do_trickle_setup)(struct ds1307 *, u32, bool); /* Does the RTC require trickle-resistor-ohms to select the value of * the resistor between Vcc and Vbackup? */ bool requires_trickle_resistor; /* Some RTC's batteries and supercaps were charged by default, others * allow charging but were not configured previously to do so. * Remember this behavior to stay backwards compatible. */ bool charge_default; }; static const struct chip_desc chips[last_ds_type]; static int ds1307_get_time(struct device *dev, struct rtc_time *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); int tmp, ret; const struct chip_desc *chip = &chips[ds1307->type]; u8 regs[7]; if (ds1307->type == rx_8130) { unsigned int regflag; ret = regmap_read(ds1307->regmap, RX8130_REG_FLAG, ®flag); if (ret) { dev_err(dev, "%s error %d\n", "read", ret); return ret; } if (regflag & RX8130_REG_FLAG_VLF) { dev_warn_once(dev, "oscillator failed, set time!\n"); return -EINVAL; } } /* read the RTC date and time registers all at once */ ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs, sizeof(regs)); if (ret) { dev_err(dev, "%s error %d\n", "read", ret); return ret; } dev_dbg(dev, "%s: %7ph\n", "read", regs); /* if oscillator fail bit is set, no data can be trusted */ if (ds1307->type == m41t0 && regs[DS1307_REG_MIN] & M41T0_BIT_OF) { dev_warn_once(dev, "oscillator failed, set time!\n"); return -EINVAL; } tmp = regs[DS1307_REG_SECS]; switch (ds1307->type) { case ds_1307: case m41t0: case m41t00: case m41t11: if (tmp & DS1307_BIT_CH) return -EINVAL; break; case ds_1308: case ds_1338: if (tmp & DS1307_BIT_CH) return -EINVAL; ret = regmap_read(ds1307->regmap, DS1307_REG_CONTROL, &tmp); if (ret) return ret; if (tmp & DS1338_BIT_OSF) return -EINVAL; break; case ds_1340: if (tmp & DS1340_BIT_nEOSC) return -EINVAL; ret = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp); if (ret) return ret; if (tmp & DS1340_BIT_OSF) return -EINVAL; break; case ds_1388: ret = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &tmp); if (ret) return ret; if (tmp & DS1388_BIT_OSF) return -EINVAL; break; case mcp794xx: if (!(tmp & MCP794XX_BIT_ST)) return -EINVAL; break; default: break; } t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f); t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f); tmp = regs[DS1307_REG_HOUR] & 0x3f; t->tm_hour = bcd2bin(tmp); /* rx8130 is bit position, not BCD */ if (ds1307->type == rx_8130) t->tm_wday = fls(regs[DS1307_REG_WDAY] & 0x7f); else t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1; t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f); tmp = regs[DS1307_REG_MONTH] & 0x1f; t->tm_mon = bcd2bin(tmp) - 1; t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100; if (regs[chip->century_reg] & chip->century_bit && IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY)) t->tm_year += 100; dev_dbg(dev, "%s secs=%d, mins=%d, " "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n", "read", t->tm_sec, t->tm_min, t->tm_hour, t->tm_mday, t->tm_mon, t->tm_year, t->tm_wday); return 0; } static int ds1307_set_time(struct device *dev, struct rtc_time *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); const struct chip_desc *chip = &chips[ds1307->type]; int result; int tmp; u8 regs[7]; dev_dbg(dev, "%s secs=%d, mins=%d, " "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n", "write", t->tm_sec, t->tm_min, t->tm_hour, t->tm_mday, t->tm_mon, t->tm_year, t->tm_wday); if (t->tm_year < 100) return -EINVAL; #ifdef CONFIG_RTC_DRV_DS1307_CENTURY if (t->tm_year > (chip->century_bit ? 299 : 199)) return -EINVAL; #else if (t->tm_year > 199) return -EINVAL; #endif regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec); regs[DS1307_REG_MIN] = bin2bcd(t->tm_min); regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour); /* rx8130 is bit position, not BCD */ if (ds1307->type == rx_8130) regs[DS1307_REG_WDAY] = 1 << t->tm_wday; else regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1); regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday); regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1); /* assume 20YY not 19YY */ tmp = t->tm_year - 100; regs[DS1307_REG_YEAR] = bin2bcd(tmp); if (chip->century_enable_bit) regs[chip->century_reg] |= chip->century_enable_bit; if (t->tm_year > 199 && chip->century_bit) regs[chip->century_reg] |= chip->century_bit; switch (ds1307->type) { case ds_1308: case ds_1338: regmap_update_bits(ds1307->regmap, DS1307_REG_CONTROL, DS1338_BIT_OSF, 0); break; case ds_1340: regmap_update_bits(ds1307->regmap, DS1340_REG_FLAG, DS1340_BIT_OSF, 0); break; case ds_1388: regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, DS1388_BIT_OSF, 0); break; case mcp794xx: /* * these bits were cleared when preparing the date/time * values and need to be set again before writing the * regsfer out to the device. */ regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST; regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN; break; default: break; } dev_dbg(dev, "%s: %7ph\n", "write", regs); result = regmap_bulk_write(ds1307->regmap, chip->offset, regs, sizeof(regs)); if (result) { dev_err(dev, "%s error %d\n", "write", result); return result; } if (ds1307->type == rx_8130) { /* clear Voltage Loss Flag as data is available now */ result = regmap_write(ds1307->regmap, RX8130_REG_FLAG, ~(u8)RX8130_REG_FLAG_VLF); if (result) { dev_err(dev, "%s error %d\n", "write", result); return result; } } return 0; } static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); int ret; u8 regs[9]; /* read all ALARM1, ALARM2, and status registers at once */ ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, sizeof(regs)); if (ret) { dev_err(dev, "%s error %d\n", "alarm read", ret); return ret; } dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read", ®s[0], ®s[4], ®s[7]); /* * report alarm time (ALARM1); assume 24 hour and day-of-month modes, * and that all four fields are checked matches */ t->time.tm_sec = bcd2bin(regs[0] & 0x7f); t->time.tm_min = bcd2bin(regs[1] & 0x7f); t->time.tm_hour = bcd2bin(regs[2] & 0x3f); t->time.tm_mday = bcd2bin(regs[3] & 0x3f); /* ... and status */ t->enabled = !!(regs[7] & DS1337_BIT_A1IE); t->pending = !!(regs[8] & DS1337_BIT_A1I); dev_dbg(dev, "%s secs=%d, mins=%d, " "hours=%d, mday=%d, enabled=%d, pending=%d\n", "alarm read", t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_mday, t->enabled, t->pending); return 0; } static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); unsigned char regs[9]; u8 control, status; int ret; dev_dbg(dev, "%s secs=%d, mins=%d, " "hours=%d, mday=%d, enabled=%d, pending=%d\n", "alarm set", t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_mday, t->enabled, t->pending); /* read current status of both alarms and the chip */ ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, sizeof(regs)); if (ret) { dev_err(dev, "%s error %d\n", "alarm write", ret); return ret; } control = regs[7]; status = regs[8]; dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)", ®s[0], ®s[4], control, status); /* set ALARM1, using 24 hour and day-of-month modes */ regs[0] = bin2bcd(t->time.tm_sec); regs[1] = bin2bcd(t->time.tm_min); regs[2] = bin2bcd(t->time.tm_hour); regs[3] = bin2bcd(t->time.tm_mday); /* set ALARM2 to non-garbage */ regs[4] = 0; regs[5] = 0; regs[6] = 0; /* disable alarms */ regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE); regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I); ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs, sizeof(regs)); if (ret) { dev_err(dev, "can't set alarm time\n"); return ret; } /* optionally enable ALARM1 */ if (t->enabled) { dev_dbg(dev, "alarm IRQ armed\n"); regs[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */ regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]); } return 0; } static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct ds1307 *ds1307 = dev_get_drvdata(dev); return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, DS1337_BIT_A1IE, enabled ? DS1337_BIT_A1IE : 0); } static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode) { u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE : DS1307_TRICKLE_CHARGER_NO_DIODE; setup |= DS13XX_TRICKLE_CHARGER_MAGIC; switch (ohms) { case 250: setup |= DS1307_TRICKLE_CHARGER_250_OHM; break; case 2000: setup |= DS1307_TRICKLE_CHARGER_2K_OHM; break; case 4000: setup |= DS1307_TRICKLE_CHARGER_4K_OHM; break; default: dev_warn(ds1307->dev, "Unsupported ohm value %u in dt\n", ohms); return 0; } return setup; } static u8 do_trickle_setup_rx8130(struct ds1307 *ds1307, u32 ohms, bool diode) { /* make sure that the backup battery is enabled */ u8 setup = RX8130_REG_CONTROL1_INIEN; if (diode) setup |= RX8130_REG_CONTROL1_CHGEN; return setup; } static irqreturn_t rx8130_irq(int irq, void *dev_id) { struct ds1307 *ds1307 = dev_id; u8 ctl[3]; int ret; rtc_lock(ds1307->rtc); /* Read control registers. */ ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, sizeof(ctl)); if (ret < 0) goto out; if (!(ctl[1] & RX8130_REG_FLAG_AF)) goto out; ctl[1] &= ~RX8130_REG_FLAG_AF; ctl[2] &= ~RX8130_REG_CONTROL0_AIE; ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl, sizeof(ctl)); if (ret < 0) goto out; rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); out: rtc_unlock(ds1307->rtc); return IRQ_HANDLED; } static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); u8 ald[3], ctl[3]; int ret; /* Read alarm registers. */ ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald, sizeof(ald)); if (ret < 0) return ret; /* Read control registers. */ ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, sizeof(ctl)); if (ret < 0) return ret; t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE); t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF); /* Report alarm 0 time assuming 24-hour and day-of-month modes. */ t->time.tm_sec = -1; t->time.tm_min = bcd2bin(ald[0] & 0x7f); t->time.tm_hour = bcd2bin(ald[1] & 0x7f); t->time.tm_wday = -1; t->time.tm_mday = bcd2bin(ald[2] & 0x7f); t->time.tm_mon = -1; t->time.tm_year = -1; t->time.tm_yday = -1; t->time.tm_isdst = -1; dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n", __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled); return 0; } static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); u8 ald[3], ctl[3]; int ret; dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " "enabled=%d pending=%d\n", __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled, t->pending); /* Read control registers. */ ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl, sizeof(ctl)); if (ret < 0) return ret; ctl[0] &= RX8130_REG_EXTENSION_WADA; ctl[1] &= ~RX8130_REG_FLAG_AF; ctl[2] &= ~RX8130_REG_CONTROL0_AIE; ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl, sizeof(ctl)); if (ret < 0) return ret; /* Hardware alarm precision is 1 minute! */ ald[0] = bin2bcd(t->time.tm_min); ald[1] = bin2bcd(t->time.tm_hour); ald[2] = bin2bcd(t->time.tm_mday); ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald, sizeof(ald)); if (ret < 0) return ret; if (!t->enabled) return 0; ctl[2] |= RX8130_REG_CONTROL0_AIE; return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]); } static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct ds1307 *ds1307 = dev_get_drvdata(dev); int ret, reg; ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, ®); if (ret < 0) return ret; if (enabled) reg |= RX8130_REG_CONTROL0_AIE; else reg &= ~RX8130_REG_CONTROL0_AIE; return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg); } static irqreturn_t mcp794xx_irq(int irq, void *dev_id) { struct ds1307 *ds1307 = dev_id; struct mutex *lock = &ds1307->rtc->ops_lock; int reg, ret; mutex_lock(lock); /* Check and clear alarm 0 interrupt flag. */ ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, ®); if (ret) goto out; if (!(reg & MCP794XX_BIT_ALMX_IF)) goto out; reg &= ~MCP794XX_BIT_ALMX_IF; ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg); if (ret) goto out; /* Disable alarm 0. */ ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL, MCP794XX_BIT_ALM0_EN, 0); if (ret) goto out; rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); out: mutex_unlock(lock); return IRQ_HANDLED; } static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); u8 regs[10]; int ret; /* Read control and alarm 0 registers. */ ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, sizeof(regs)); if (ret) return ret; t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN); /* Report alarm 0 time assuming 24-hour and day-of-month modes. */ t->time.tm_sec = bcd2bin(regs[3] & 0x7f); t->time.tm_min = bcd2bin(regs[4] & 0x7f); t->time.tm_hour = bcd2bin(regs[5] & 0x3f); t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1; t->time.tm_mday = bcd2bin(regs[7] & 0x3f); t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1; t->time.tm_year = -1; t->time.tm_yday = -1; t->time.tm_isdst = -1; dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " "enabled=%d polarity=%d irq=%d match=%lu\n", __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled, !!(regs[6] & MCP794XX_BIT_ALMX_POL), !!(regs[6] & MCP794XX_BIT_ALMX_IF), (regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4); return 0; } /* * We may have a random RTC weekday, therefore calculate alarm weekday based * on current weekday we read from the RTC timekeeping regs */ static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm) { struct rtc_time tm_now; int days_now, days_alarm, ret; ret = ds1307_get_time(dev, &tm_now); if (ret) return ret; days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60); days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60); return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1; } static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct ds1307 *ds1307 = dev_get_drvdata(dev); unsigned char regs[10]; int wday, ret; wday = mcp794xx_alm_weekday(dev, &t->time); if (wday < 0) return wday; dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d " "enabled=%d pending=%d\n", __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled, t->pending); /* Read control and alarm 0 registers. */ ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs, sizeof(regs)); if (ret) return ret; /* Set alarm 0, using 24-hour and day-of-month modes. */ regs[3] = bin2bcd(t->time.tm_sec); regs[4] = bin2bcd(t->time.tm_min); regs[5] = bin2bcd(t->time.tm_hour); regs[6] = wday; regs[7] = bin2bcd(t->time.tm_mday); regs[8] = bin2bcd(t->time.tm_mon + 1); /* Clear the alarm 0 interrupt flag. */ regs[6] &= ~MCP794XX_BIT_ALMX_IF; /* Set alarm match: second, minute, hour, day, date, month. */ regs[6] |= MCP794XX_MSK_ALMX_MATCH; /* Disable interrupt. We will not enable until completely programmed */ regs[0] &= ~MCP794XX_BIT_ALM0_EN; ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs, sizeof(regs)); if (ret) return ret; if (!t->enabled) return 0; regs[0] |= MCP794XX_BIT_ALM0_EN; return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]); } static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct ds1307 *ds1307 = dev_get_drvdata(dev); return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL, MCP794XX_BIT_ALM0_EN, enabled ? MCP794XX_BIT_ALM0_EN : 0); } static int m41txx_rtc_read_offset(struct device *dev, long *offset) { struct ds1307 *ds1307 = dev_get_drvdata(dev); unsigned int ctrl_reg; u8 val; regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); val = ctrl_reg & M41TXX_M_CALIBRATION; /* check if positive */ if (ctrl_reg & M41TXX_BIT_CALIB_SIGN) *offset = (val * M41TXX_POS_OFFSET_STEP_PPB); else *offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB); return 0; } static int m41txx_rtc_set_offset(struct device *dev, long offset) { struct ds1307 *ds1307 = dev_get_drvdata(dev); unsigned int ctrl_reg; if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET)) return -ERANGE; if (offset >= 0) { ctrl_reg = DIV_ROUND_CLOSEST(offset, M41TXX_POS_OFFSET_STEP_PPB); ctrl_reg |= M41TXX_BIT_CALIB_SIGN; } else { ctrl_reg = DIV_ROUND_CLOSEST(abs(offset), M41TXX_NEG_OFFSET_STEP_PPB); } return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN, ctrl_reg); } #ifdef CONFIG_WATCHDOG_CORE static int ds1388_wdt_start(struct watchdog_device *wdt_dev) { struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); u8 regs[2]; int ret; ret = regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, DS1388_BIT_WF, 0); if (ret) return ret; ret = regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, DS1388_BIT_WDE | DS1388_BIT_RST, 0); if (ret) return ret; /* * watchdog timeouts are measured in seconds. So ignore hundredths of * seconds field. */ regs[0] = 0; regs[1] = bin2bcd(wdt_dev->timeout); ret = regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, sizeof(regs)); if (ret) return ret; return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, DS1388_BIT_WDE | DS1388_BIT_RST, DS1388_BIT_WDE | DS1388_BIT_RST); } static int ds1388_wdt_stop(struct watchdog_device *wdt_dev) { struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); return regmap_update_bits(ds1307->regmap, DS1388_REG_CONTROL, DS1388_BIT_WDE | DS1388_BIT_RST, 0); } static int ds1388_wdt_ping(struct watchdog_device *wdt_dev) { struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); u8 regs[2]; return regmap_bulk_read(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, sizeof(regs)); } static int ds1388_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int val) { struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); u8 regs[2]; wdt_dev->timeout = val; regs[0] = 0; regs[1] = bin2bcd(wdt_dev->timeout); return regmap_bulk_write(ds1307->regmap, DS1388_REG_WDOG_HUN_SECS, regs, sizeof(regs)); } #endif static const struct rtc_class_ops rx8130_rtc_ops = { .read_time = ds1307_get_time, .set_time = ds1307_set_time, .read_alarm = rx8130_read_alarm, .set_alarm = rx8130_set_alarm, .alarm_irq_enable = rx8130_alarm_irq_enable, }; static const struct rtc_class_ops mcp794xx_rtc_ops = { .read_time = ds1307_get_time, .set_time = ds1307_set_time, .read_alarm = mcp794xx_read_alarm, .set_alarm = mcp794xx_set_alarm, .alarm_irq_enable = mcp794xx_alarm_irq_enable, }; static const struct rtc_class_ops m41txx_rtc_ops = { .read_time = ds1307_get_time, .set_time = ds1307_set_time, .read_alarm = ds1337_read_alarm, .set_alarm = ds1337_set_alarm, .alarm_irq_enable = ds1307_alarm_irq_enable, .read_offset = m41txx_rtc_read_offset, .set_offset = m41txx_rtc_set_offset, }; static const struct chip_desc chips[last_ds_type] = { [ds_1307] = { .nvram_offset = 8, .nvram_size = 56, }, [ds_1308] = { .nvram_offset = 8, .nvram_size = 56, }, [ds_1337] = { .alarm = 1, .century_reg = DS1307_REG_MONTH, .century_bit = DS1337_BIT_CENTURY, }, [ds_1338] = { .nvram_offset = 8, .nvram_size = 56, }, [ds_1339] = { .alarm = 1, .century_reg = DS1307_REG_MONTH, .century_bit = DS1337_BIT_CENTURY, .bbsqi_bit = DS1339_BIT_BBSQI, .trickle_charger_reg = 0x10, .do_trickle_setup = &do_trickle_setup_ds1339, .requires_trickle_resistor = true, .charge_default = true, }, [ds_1340] = { .century_reg = DS1307_REG_HOUR, .century_enable_bit = DS1340_BIT_CENTURY_EN, .century_bit = DS1340_BIT_CENTURY, .do_trickle_setup = &do_trickle_setup_ds1339, .trickle_charger_reg = 0x08, .requires_trickle_resistor = true, .charge_default = true, }, [ds_1341] = { .century_reg = DS1307_REG_MONTH, .century_bit = DS1337_BIT_CENTURY, }, [ds_1388] = { .offset = 1, .trickle_charger_reg = 0x0a, }, [ds_3231] = { .alarm = 1, .century_reg = DS1307_REG_MONTH, .century_bit = DS1337_BIT_CENTURY, .bbsqi_bit = DS3231_BIT_BBSQW, }, [rx_8130] = { .alarm = 1, /* this is battery backed SRAM */ .nvram_offset = 0x20, .nvram_size = 4, /* 32bit (4 word x 8 bit) */ .offset = 0x10, .irq_handler = rx8130_irq, .rtc_ops = &rx8130_rtc_ops, .trickle_charger_reg = RX8130_REG_CONTROL1, .do_trickle_setup = &do_trickle_setup_rx8130, }, [m41t0] = { .rtc_ops = &m41txx_rtc_ops, }, [m41t00] = { .rtc_ops = &m41txx_rtc_ops, }, [m41t11] = { /* this is battery backed SRAM */ .nvram_offset = 8, .nvram_size = 56, .rtc_ops = &m41txx_rtc_ops, }, [mcp794xx] = { .alarm = 1, /* this is battery backed SRAM */ .nvram_offset = 0x20, .nvram_size = 0x40, .irq_handler = mcp794xx_irq, .rtc_ops = &mcp794xx_rtc_ops, }, }; static const struct i2c_device_id ds1307_id[] = { { "ds1307", ds_1307 }, { "ds1308", ds_1308 }, { "ds1337", ds_1337 }, { "ds1338", ds_1338 }, { "ds1339", ds_1339 }, { "ds1388", ds_1388 }, { "ds1340", ds_1340 }, { "ds1341", ds_1341 }, { "ds3231", ds_3231 }, { "m41t0", m41t0 }, { "m41t00", m41t00 }, { "m41t11", m41t11 }, { "mcp7940x", mcp794xx }, { "mcp7941x", mcp794xx }, { "pt7c4338", ds_1307 }, { "rx8025", rx_8025 }, { "isl12057", ds_1337 }, { "rx8130", rx_8130 }, { } }; MODULE_DEVICE_TABLE(i2c, ds1307_id); static const struct of_device_id ds1307_of_match[] = { { .compatible = "dallas,ds1307", .data = (void *)ds_1307 }, { .compatible = "dallas,ds1308", .data = (void *)ds_1308 }, { .compatible = "dallas,ds1337", .data = (void *)ds_1337 }, { .compatible = "dallas,ds1338", .data = (void *)ds_1338 }, { .compatible = "dallas,ds1339", .data = (void *)ds_1339 }, { .compatible = "dallas,ds1388", .data = (void *)ds_1388 }, { .compatible = "dallas,ds1340", .data = (void *)ds_1340 }, { .compatible = "dallas,ds1341", .data = (void *)ds_1341 }, { .compatible = "maxim,ds3231", .data = (void *)ds_3231 }, { .compatible = "st,m41t0", .data = (void *)m41t0 }, { .compatible = "st,m41t00", .data = (void *)m41t00 }, { .compatible = "st,m41t11", .data = (void *)m41t11 }, { .compatible = "microchip,mcp7940x", .data = (void *)mcp794xx }, { .compatible = "microchip,mcp7941x", .data = (void *)mcp794xx }, { .compatible = "pericom,pt7c4338", .data = (void *)ds_1307 }, { .compatible = "epson,rx8025", .data = (void *)rx_8025 }, { .compatible = "isil,isl12057", .data = (void *)ds_1337 }, { .compatible = "epson,rx8130", .data = (void *)rx_8130 }, { } }; MODULE_DEVICE_TABLE(of, ds1307_of_match); /* * The ds1337 and ds1339 both have two alarms, but we only use the first * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm * signal; ds1339 chips have only one alarm signal. */ static irqreturn_t ds1307_irq(int irq, void *dev_id) { struct ds1307 *ds1307 = dev_id; struct mutex *lock = &ds1307->rtc->ops_lock; int stat, ret; mutex_lock(lock); ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat); if (ret) goto out; if (stat & DS1337_BIT_A1I) { stat &= ~DS1337_BIT_A1I; regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat); ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, DS1337_BIT_A1IE, 0); if (ret) goto out; rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF); } out: mutex_unlock(lock); return IRQ_HANDLED; } /*----------------------------------------------------------------------*/ static const struct rtc_class_ops ds13xx_rtc_ops = { .read_time = ds1307_get_time, .set_time = ds1307_set_time, .read_alarm = ds1337_read_alarm, .set_alarm = ds1337_set_alarm, .alarm_irq_enable = ds1307_alarm_irq_enable, }; static ssize_t frequency_test_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); bool freq_test_en; int ret; ret = kstrtobool(buf, &freq_test_en); if (ret) { dev_err(dev, "Failed to store RTC Frequency Test attribute\n"); return ret; } regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT, freq_test_en ? M41TXX_BIT_FT : 0); return count; } static ssize_t frequency_test_show(struct device *dev, struct device_attribute *attr, char *buf) { struct ds1307 *ds1307 = dev_get_drvdata(dev->parent); unsigned int ctrl_reg; regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); return sysfs_emit(buf, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" : "off\n"); } static DEVICE_ATTR_RW(frequency_test); static struct attribute *rtc_freq_test_attrs[] = { &dev_attr_frequency_test.attr, NULL, }; static const struct attribute_group rtc_freq_test_attr_group = { .attrs = rtc_freq_test_attrs, }; static int ds1307_add_frequency_test(struct ds1307 *ds1307) { int err; switch (ds1307->type) { case m41t0: case m41t00: case m41t11: err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group); if (err) return err; break; default: break; } return 0; } /*----------------------------------------------------------------------*/ static int ds1307_nvram_read(void *priv, unsigned int offset, void *val, size_t bytes) { struct ds1307 *ds1307 = priv; const struct chip_desc *chip = &chips[ds1307->type]; return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset, val, bytes); } static int ds1307_nvram_write(void *priv, unsigned int offset, void *val, size_t bytes) { struct ds1307 *ds1307 = priv; const struct chip_desc *chip = &chips[ds1307->type]; return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset, val, bytes); } /*----------------------------------------------------------------------*/ static u8 ds1307_trickle_init(struct ds1307 *ds1307, const struct chip_desc *chip) { u32 ohms, chargeable; bool diode = chip->charge_default; if (!chip->do_trickle_setup) return 0; if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms", &ohms) && chip->requires_trickle_resistor) return 0; /* aux-voltage-chargeable takes precedence over the deprecated * trickle-diode-disable */ if (!device_property_read_u32(ds1307->dev, "aux-voltage-chargeable", &chargeable)) { switch (chargeable) { case 0: diode = false; break; case 1: diode = true; break; default: dev_warn(ds1307->dev, "unsupported aux-voltage-chargeable value\n"); break; } } else if (device_property_read_bool(ds1307->dev, "trickle-diode-disable")) { diode = false; } return chip->do_trickle_setup(ds1307, ohms, diode); } /*----------------------------------------------------------------------*/ #if IS_REACHABLE(CONFIG_HWMON) /* * Temperature sensor support for ds3231 devices. */ #define DS3231_REG_TEMPERATURE 0x11 /* * A user-initiated temperature conversion is not started by this function, * so the temperature is updated once every 64 seconds. */ static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC) { struct ds1307 *ds1307 = dev_get_drvdata(dev); u8 temp_buf[2]; s16 temp; int ret; ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE, temp_buf, sizeof(temp_buf)); if (ret) return ret; /* * Temperature is represented as a 10-bit code with a resolution of * 0.25 degree celsius and encoded in two's complement format. */ temp = (temp_buf[0] << 8) | temp_buf[1]; temp >>= 6; *mC = temp * 250; return 0; } static ssize_t ds3231_hwmon_show_temp(struct device *dev, struct device_attribute *attr, char *buf) { int ret; s32 temp; ret = ds3231_hwmon_read_temp(dev, &temp); if (ret) return ret; return sprintf(buf, "%d\n", temp); } static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp, NULL, 0); static struct attribute *ds3231_hwmon_attrs[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, NULL, }; ATTRIBUTE_GROUPS(ds3231_hwmon); static void ds1307_hwmon_register(struct ds1307 *ds1307) { struct device *dev; if (ds1307->type != ds_3231) return; dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name, ds1307, ds3231_hwmon_groups); if (IS_ERR(dev)) { dev_warn(ds1307->dev, "unable to register hwmon device %ld\n", PTR_ERR(dev)); } } #else static void ds1307_hwmon_register(struct ds1307 *ds1307) { } #endif /* CONFIG_RTC_DRV_DS1307_HWMON */ /*----------------------------------------------------------------------*/ /* * Square-wave output support for DS3231 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf */ #ifdef CONFIG_COMMON_CLK enum { DS3231_CLK_SQW = 0, DS3231_CLK_32KHZ, }; #define clk_sqw_to_ds1307(clk) \ container_of(clk, struct ds1307, clks[DS3231_CLK_SQW]) #define clk_32khz_to_ds1307(clk) \ container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ]) static int ds3231_clk_sqw_rates[] = { 1, 1024, 4096, 8192, }; static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value) { struct mutex *lock = &ds1307->rtc->ops_lock; int ret; mutex_lock(lock); ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL, mask, value); mutex_unlock(lock); return ret; } static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); int control, ret; int rate_sel = 0; ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control); if (ret) return ret; if (control & DS1337_BIT_RS1) rate_sel += 1; if (control & DS1337_BIT_RS2) rate_sel += 2; return ds3231_clk_sqw_rates[rate_sel]; } static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate) { int i; for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) { if (ds3231_clk_sqw_rates[i] <= rate) return ds3231_clk_sqw_rates[i]; } return 0; } static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); int control = 0; int rate_sel; for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates); rate_sel++) { if (ds3231_clk_sqw_rates[rate_sel] == rate) break; } if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates)) return -EINVAL; if (rate_sel & 1) control |= DS1337_BIT_RS1; if (rate_sel & 2) control |= DS1337_BIT_RS2; return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2, control); } static int ds3231_clk_sqw_prepare(struct clk_hw *hw) { struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0); } static void ds3231_clk_sqw_unprepare(struct clk_hw *hw) { struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN); } static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw) { struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw); int control, ret; ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control); if (ret) return ret; return !(control & DS1337_BIT_INTCN); } static const struct clk_ops ds3231_clk_sqw_ops = { .prepare = ds3231_clk_sqw_prepare, .unprepare = ds3231_clk_sqw_unprepare, .is_prepared = ds3231_clk_sqw_is_prepared, .recalc_rate = ds3231_clk_sqw_recalc_rate, .round_rate = ds3231_clk_sqw_round_rate, .set_rate = ds3231_clk_sqw_set_rate, }; static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { return 32768; } static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable) { struct mutex *lock = &ds1307->rtc->ops_lock; int ret; mutex_lock(lock); ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS, DS3231_BIT_EN32KHZ, enable ? DS3231_BIT_EN32KHZ : 0); mutex_unlock(lock); return ret; } static int ds3231_clk_32khz_prepare(struct clk_hw *hw) { struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); return ds3231_clk_32khz_control(ds1307, true); } static void ds3231_clk_32khz_unprepare(struct clk_hw *hw) { struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); ds3231_clk_32khz_control(ds1307, false); } static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw) { struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw); int status, ret; ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status); if (ret) return ret; return !!(status & DS3231_BIT_EN32KHZ); } static const struct clk_ops ds3231_clk_32khz_ops = { .prepare = ds3231_clk_32khz_prepare, .unprepare = ds3231_clk_32khz_unprepare, .is_prepared = ds3231_clk_32khz_is_prepared, .recalc_rate = ds3231_clk_32khz_recalc_rate, }; static const char *ds3231_clks_names[] = { [DS3231_CLK_SQW] = "ds3231_clk_sqw", [DS3231_CLK_32KHZ] = "ds3231_clk_32khz", }; static struct clk_init_data ds3231_clks_init[] = { [DS3231_CLK_SQW] = { .ops = &ds3231_clk_sqw_ops, }, [DS3231_CLK_32KHZ] = { .ops = &ds3231_clk_32khz_ops, }, }; static int ds3231_clks_register(struct ds1307 *ds1307) { struct device_node *node = ds1307->dev->of_node; struct clk_onecell_data *onecell; int i; onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL); if (!onecell) return -ENOMEM; onecell->clk_num = ARRAY_SIZE(ds3231_clks_init); onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num, sizeof(onecell->clks[0]), GFP_KERNEL); if (!onecell->clks) return -ENOMEM; /* optional override of the clockname */ device_property_read_string_array(ds1307->dev, "clock-output-names", ds3231_clks_names, ARRAY_SIZE(ds3231_clks_names)); for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) { struct clk_init_data init = ds3231_clks_init[i]; /* * Interrupt signal due to alarm conditions and square-wave * output share same pin, so don't initialize both. */ if (i == DS3231_CLK_SQW && test_bit(RTC_FEATURE_ALARM, ds1307->rtc->features)) continue; init.name = ds3231_clks_names[i]; ds1307->clks[i].init = &init; onecell->clks[i] = devm_clk_register(ds1307->dev, &ds1307->clks[i]); if (IS_ERR(onecell->clks[i])) return PTR_ERR(onecell->clks[i]); } if (node) of_clk_add_provider(node, of_clk_src_onecell_get, onecell); return 0; } static void ds1307_clks_register(struct ds1307 *ds1307) { int ret; if (ds1307->type != ds_3231) return; ret = ds3231_clks_register(ds1307); if (ret) { dev_warn(ds1307->dev, "unable to register clock device %d\n", ret); } } #else static void ds1307_clks_register(struct ds1307 *ds1307) { } #endif /* CONFIG_COMMON_CLK */ #ifdef CONFIG_WATCHDOG_CORE static const struct watchdog_info ds1388_wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "DS1388 watchdog", }; static const struct watchdog_ops ds1388_wdt_ops = { .owner = THIS_MODULE, .start = ds1388_wdt_start, .stop = ds1388_wdt_stop, .ping = ds1388_wdt_ping, .set_timeout = ds1388_wdt_set_timeout, }; static void ds1307_wdt_register(struct ds1307 *ds1307) { struct watchdog_device *wdt; int err; int val; if (ds1307->type != ds_1388) return; wdt = devm_kzalloc(ds1307->dev, sizeof(*wdt), GFP_KERNEL); if (!wdt) return; err = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &val); if (!err && val & DS1388_BIT_WF) wdt->bootstatus = WDIOF_CARDRESET; wdt->info = &ds1388_wdt_info; wdt->ops = &ds1388_wdt_ops; wdt->timeout = 99; wdt->max_timeout = 99; wdt->min_timeout = 1; watchdog_init_timeout(wdt, 0, ds1307->dev); watchdog_set_drvdata(wdt, ds1307); devm_watchdog_register_device(ds1307->dev, wdt); } #else static void ds1307_wdt_register(struct ds1307 *ds1307) { } #endif /* CONFIG_WATCHDOG_CORE */ static const struct regmap_config regmap_config = { .reg_bits = 8, .val_bits = 8, }; static int ds1307_probe(struct i2c_client *client) { const struct i2c_device_id *id = i2c_client_get_device_id(client); struct ds1307 *ds1307; const void *match; int err = -ENODEV; int tmp; const struct chip_desc *chip; bool want_irq; bool ds1307_can_wakeup_device = false; unsigned char regs[8]; struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev); u8 trickle_charger_setup = 0; ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL); if (!ds1307) return -ENOMEM; dev_set_drvdata(&client->dev, ds1307); ds1307->dev = &client->dev; ds1307->name = client->name; ds1307->regmap = devm_regmap_init_i2c(client, ®map_config); if (IS_ERR(ds1307->regmap)) { dev_err(ds1307->dev, "regmap allocation failed\n"); return PTR_ERR(ds1307->regmap); } i2c_set_clientdata(client, ds1307); match = device_get_match_data(&client->dev); if (match) { ds1307->type = (uintptr_t)match; chip = &chips[ds1307->type]; } else if (id) { chip = &chips[id->driver_data]; ds1307->type = id->driver_data; } else { return -ENODEV; } want_irq = client->irq > 0 && chip->alarm; if (!pdata) trickle_charger_setup = ds1307_trickle_init(ds1307, chip); else if (pdata->trickle_charger_setup) trickle_charger_setup = pdata->trickle_charger_setup; if (trickle_charger_setup && chip->trickle_charger_reg) { dev_dbg(ds1307->dev, "writing trickle charger info 0x%x to 0x%x\n", trickle_charger_setup, chip->trickle_charger_reg); regmap_write(ds1307->regmap, chip->trickle_charger_reg, trickle_charger_setup); } /* * For devices with no IRQ directly connected to the SoC, the RTC chip * can be forced as a wakeup source by stating that explicitly in * the device's .dts file using the "wakeup-source" boolean property. * If the "wakeup-source" property is set, don't request an IRQ. * This will guarantee the 'wakealarm' sysfs entry is available on the device, * if supported by the RTC. */ if (chip->alarm && device_property_read_bool(&client->dev, "wakeup-source")) ds1307_can_wakeup_device = true; switch (ds1307->type) { case ds_1337: case ds_1339: case ds_1341: case ds_3231: /* get registers that the "rtc" read below won't read... */ err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL, regs, 2); if (err) { dev_dbg(ds1307->dev, "read error %d\n", err); goto exit; } /* oscillator off? turn it on, so clock can tick. */ if (regs[0] & DS1337_BIT_nEOSC) regs[0] &= ~DS1337_BIT_nEOSC; /* * Using IRQ or defined as wakeup-source? * Disable the square wave and both alarms. * For some variants, be sure alarms can trigger when we're * running on Vbackup (BBSQI/BBSQW) */ if (want_irq || ds1307_can_wakeup_device) { regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit; regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE); } regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[0]); /* oscillator fault? clear flag, and warn */ if (regs[1] & DS1337_BIT_OSF) { regmap_write(ds1307->regmap, DS1337_REG_STATUS, regs[1] & ~DS1337_BIT_OSF); dev_warn(ds1307->dev, "SET TIME!\n"); } break; case rx_8025: err = regmap_bulk_read(ds1307->regmap, RX8025_REG_CTRL1 << 4 | 0x08, regs, 2); if (err) { dev_dbg(ds1307->dev, "read error %d\n", err); goto exit; } /* oscillator off? turn it on, so clock can tick. */ if (!(regs[1] & RX8025_BIT_XST)) { regs[1] |= RX8025_BIT_XST; regmap_write(ds1307->regmap, RX8025_REG_CTRL2 << 4 | 0x08, regs[1]); dev_warn(ds1307->dev, "oscillator stop detected - SET TIME!\n"); } if (regs[1] & RX8025_BIT_PON) { regs[1] &= ~RX8025_BIT_PON; regmap_write(ds1307->regmap, RX8025_REG_CTRL2 << 4 | 0x08, regs[1]); dev_warn(ds1307->dev, "power-on detected\n"); } if (regs[1] & RX8025_BIT_VDET) { regs[1] &= ~RX8025_BIT_VDET; regmap_write(ds1307->regmap, RX8025_REG_CTRL2 << 4 | 0x08, regs[1]); dev_warn(ds1307->dev, "voltage drop detected\n"); } /* make sure we are running in 24hour mode */ if (!(regs[0] & RX8025_BIT_2412)) { u8 hour; /* switch to 24 hour mode */ regmap_write(ds1307->regmap, RX8025_REG_CTRL1 << 4 | 0x08, regs[0] | RX8025_BIT_2412); err = regmap_bulk_read(ds1307->regmap, RX8025_REG_CTRL1 << 4 | 0x08, regs, 2); if (err) { dev_dbg(ds1307->dev, "read error %d\n", err); goto exit; } /* correct hour */ hour = bcd2bin(regs[DS1307_REG_HOUR]); if (hour == 12) hour = 0; if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM) hour += 12; regmap_write(ds1307->regmap, DS1307_REG_HOUR << 4 | 0x08, hour); } break; case ds_1388: err = regmap_read(ds1307->regmap, DS1388_REG_CONTROL, &tmp); if (err) { dev_dbg(ds1307->dev, "read error %d\n", err); goto exit; } /* oscillator off? turn it on, so clock can tick. */ if (tmp & DS1388_BIT_nEOSC) { tmp &= ~DS1388_BIT_nEOSC; regmap_write(ds1307->regmap, DS1388_REG_CONTROL, tmp); } break; default: break; } /* read RTC registers */ err = regmap_bulk_read(ds1307->regmap, chip->offset, regs, sizeof(regs)); if (err) { dev_dbg(ds1307->dev, "read error %d\n", err); goto exit; } if (ds1307->type == mcp794xx && !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) { regmap_write(ds1307->regmap, DS1307_REG_WDAY, regs[DS1307_REG_WDAY] | MCP794XX_BIT_VBATEN); } tmp = regs[DS1307_REG_HOUR]; switch (ds1307->type) { case ds_1340: case m41t0: case m41t00: case m41t11: /* * NOTE: ignores century bits; fix before deploying * systems that will run through year 2100. */ break; case rx_8025: break; default: if (!(tmp & DS1307_BIT_12HR)) break; /* * Be sure we're in 24 hour mode. Multi-master systems * take note... */ tmp = bcd2bin(tmp & 0x1f); if (tmp == 12) tmp = 0; if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM) tmp += 12; regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR, bin2bcd(tmp)); } ds1307->rtc = devm_rtc_allocate_device(ds1307->dev); if (IS_ERR(ds1307->rtc)) return PTR_ERR(ds1307->rtc); if (want_irq || ds1307_can_wakeup_device) device_set_wakeup_capable(ds1307->dev, true); else clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features); if (ds1307_can_wakeup_device && !want_irq) { dev_info(ds1307->dev, "'wakeup-source' is set, request for an IRQ is disabled!\n"); /* We cannot support UIE mode if we do not have an IRQ line */ clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, ds1307->rtc->features); } if (want_irq) { err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL, chip->irq_handler ?: ds1307_irq, IRQF_SHARED | IRQF_ONESHOT, ds1307->name, ds1307); if (err) { client->irq = 0; device_set_wakeup_capable(ds1307->dev, false); clear_bit(RTC_FEATURE_ALARM, ds1307->rtc->features); dev_err(ds1307->dev, "unable to request IRQ!\n"); } else { dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq); } } ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops; err = ds1307_add_frequency_test(ds1307); if (err) return err; err = devm_rtc_register_device(ds1307->rtc); if (err) return err; if (chip->nvram_size) { struct nvmem_config nvmem_cfg = { .name = "ds1307_nvram", .word_size = 1, .stride = 1, .size = chip->nvram_size, .reg_read = ds1307_nvram_read, .reg_write = ds1307_nvram_write, .priv = ds1307, }; devm_rtc_nvmem_register(ds1307->rtc, &nvmem_cfg); } ds1307_hwmon_register(ds1307); ds1307_clks_register(ds1307); ds1307_wdt_register(ds1307); return 0; exit: return err; } static struct i2c_driver ds1307_driver = { .driver = { .name = "rtc-ds1307", .of_match_table = ds1307_of_match, }, .probe = ds1307_probe, .id_table = ds1307_id, }; module_i2c_driver(ds1307_driver); MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips"); MODULE_LICENSE("GPL");