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- /*
- * 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)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
- #include <linux/bcd.h>
- #include <linux/i2c.h>
- #include <linux/init.h>
- #include <linux/module.h>
- #include <linux/rtc/ds1307.h>
- #include <linux/rtc.h>
- #include <linux/slab.h>
- #include <linux/string.h>
- /*
- * 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 {
- ds_1307,
- ds_1337,
- ds_1338,
- ds_1339,
- ds_1340,
- ds_1388,
- ds_3231,
- m41t00,
- mcp794xx,
- rx_8025,
- 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 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 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
- struct ds1307 {
- u8 offset; /* register's offset */
- u8 regs[11];
- u16 nvram_offset;
- struct bin_attribute *nvram;
- enum ds_type type;
- unsigned long flags;
- #define HAS_NVRAM 0 /* bit 0 == sysfs file active */
- #define HAS_ALARM 1 /* bit 1 == irq claimed */
- struct i2c_client *client;
- struct rtc_device *rtc;
- s32 (*read_block_data)(const struct i2c_client *client, u8 command,
- u8 length, u8 *values);
- s32 (*write_block_data)(const struct i2c_client *client, u8 command,
- u8 length, const u8 *values);
- };
- struct chip_desc {
- unsigned alarm:1;
- u16 nvram_offset;
- u16 nvram_size;
- u16 trickle_charger_reg;
- u8 trickle_charger_setup;
- u8 (*do_trickle_setup)(struct i2c_client *, uint32_t, bool);
- };
- static u8 do_trickle_setup_ds1339(struct i2c_client *,
- uint32_t ohms, bool diode);
- static struct chip_desc chips[last_ds_type] = {
- [ds_1307] = {
- .nvram_offset = 8,
- .nvram_size = 56,
- },
- [ds_1337] = {
- .alarm = 1,
- },
- [ds_1338] = {
- .nvram_offset = 8,
- .nvram_size = 56,
- },
- [ds_1339] = {
- .alarm = 1,
- .trickle_charger_reg = 0x10,
- .do_trickle_setup = &do_trickle_setup_ds1339,
- },
- [ds_1340] = {
- .trickle_charger_reg = 0x08,
- },
- [ds_1388] = {
- .trickle_charger_reg = 0x0a,
- },
- [ds_3231] = {
- .alarm = 1,
- },
- [mcp794xx] = {
- .alarm = 1,
- /* this is battery backed SRAM */
- .nvram_offset = 0x20,
- .nvram_size = 0x40,
- },
- };
- static const struct i2c_device_id ds1307_id[] = {
- { "ds1307", ds_1307 },
- { "ds1337", ds_1337 },
- { "ds1338", ds_1338 },
- { "ds1339", ds_1339 },
- { "ds1388", ds_1388 },
- { "ds1340", ds_1340 },
- { "ds3231", ds_3231 },
- { "m41t00", m41t00 },
- { "mcp7940x", mcp794xx },
- { "mcp7941x", mcp794xx },
- { "pt7c4338", ds_1307 },
- { "rx8025", rx_8025 },
- { }
- };
- MODULE_DEVICE_TABLE(i2c, ds1307_id);
- /*----------------------------------------------------------------------*/
- #define BLOCK_DATA_MAX_TRIES 10
- static s32 ds1307_read_block_data_once(const struct i2c_client *client,
- u8 command, u8 length, u8 *values)
- {
- s32 i, data;
- for (i = 0; i < length; i++) {
- data = i2c_smbus_read_byte_data(client, command + i);
- if (data < 0)
- return data;
- values[i] = data;
- }
- return i;
- }
- static s32 ds1307_read_block_data(const struct i2c_client *client, u8 command,
- u8 length, u8 *values)
- {
- u8 oldvalues[255];
- s32 ret;
- int tries = 0;
- dev_dbg(&client->dev, "ds1307_read_block_data (length=%d)\n", length);
- ret = ds1307_read_block_data_once(client, command, length, values);
- if (ret < 0)
- return ret;
- do {
- if (++tries > BLOCK_DATA_MAX_TRIES) {
- dev_err(&client->dev,
- "ds1307_read_block_data failed\n");
- return -EIO;
- }
- memcpy(oldvalues, values, length);
- ret = ds1307_read_block_data_once(client, command, length,
- values);
- if (ret < 0)
- return ret;
- } while (memcmp(oldvalues, values, length));
- return length;
- }
- static s32 ds1307_write_block_data(const struct i2c_client *client, u8 command,
- u8 length, const u8 *values)
- {
- u8 currvalues[255];
- int tries = 0;
- dev_dbg(&client->dev, "ds1307_write_block_data (length=%d)\n", length);
- do {
- s32 i, ret;
- if (++tries > BLOCK_DATA_MAX_TRIES) {
- dev_err(&client->dev,
- "ds1307_write_block_data failed\n");
- return -EIO;
- }
- for (i = 0; i < length; i++) {
- ret = i2c_smbus_write_byte_data(client, command + i,
- values[i]);
- if (ret < 0)
- return ret;
- }
- ret = ds1307_read_block_data_once(client, command, length,
- currvalues);
- if (ret < 0)
- return ret;
- } while (memcmp(currvalues, values, length));
- return length;
- }
- /*----------------------------------------------------------------------*/
- /* These RTC devices are not designed to be connected to a SMbus adapter.
- SMbus limits block operations length to 32 bytes, whereas it's not
- limited on I2C buses. As a result, accesses may exceed 32 bytes;
- in that case, split them into smaller blocks */
- static s32 ds1307_native_smbus_write_block_data(const struct i2c_client *client,
- u8 command, u8 length, const u8 *values)
- {
- u8 suboffset = 0;
- if (length <= I2C_SMBUS_BLOCK_MAX)
- return i2c_smbus_write_i2c_block_data(client,
- command, length, values);
- while (suboffset < length) {
- s32 retval = i2c_smbus_write_i2c_block_data(client,
- command + suboffset,
- min(I2C_SMBUS_BLOCK_MAX, length - suboffset),
- values + suboffset);
- if (retval < 0)
- return retval;
- suboffset += I2C_SMBUS_BLOCK_MAX;
- }
- return length;
- }
- static s32 ds1307_native_smbus_read_block_data(const struct i2c_client *client,
- u8 command, u8 length, u8 *values)
- {
- u8 suboffset = 0;
- if (length <= I2C_SMBUS_BLOCK_MAX)
- return i2c_smbus_read_i2c_block_data(client,
- command, length, values);
- while (suboffset < length) {
- s32 retval = i2c_smbus_read_i2c_block_data(client,
- command + suboffset,
- min(I2C_SMBUS_BLOCK_MAX, length - suboffset),
- values + suboffset);
- if (retval < 0)
- return retval;
- suboffset += I2C_SMBUS_BLOCK_MAX;
- }
- return length;
- }
- /*----------------------------------------------------------------------*/
- /*
- * 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 i2c_client *client = dev_id;
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- struct mutex *lock = &ds1307->rtc->ops_lock;
- int stat, control;
- mutex_lock(lock);
- stat = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS);
- if (stat < 0)
- goto out;
- if (stat & DS1337_BIT_A1I) {
- stat &= ~DS1337_BIT_A1I;
- i2c_smbus_write_byte_data(client, DS1337_REG_STATUS, stat);
- control = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
- if (control < 0)
- goto out;
- control &= ~DS1337_BIT_A1IE;
- i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, control);
- rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
- }
- out:
- mutex_unlock(lock);
- return IRQ_HANDLED;
- }
- /*----------------------------------------------------------------------*/
- static int ds1307_get_time(struct device *dev, struct rtc_time *t)
- {
- struct ds1307 *ds1307 = dev_get_drvdata(dev);
- int tmp;
- /* read the RTC date and time registers all at once */
- tmp = ds1307->read_block_data(ds1307->client,
- ds1307->offset, 7, ds1307->regs);
- if (tmp != 7) {
- dev_err(dev, "%s error %d\n", "read", tmp);
- return -EIO;
- }
- dev_dbg(dev, "%s: %7ph\n", "read", ds1307->regs);
- t->tm_sec = bcd2bin(ds1307->regs[DS1307_REG_SECS] & 0x7f);
- t->tm_min = bcd2bin(ds1307->regs[DS1307_REG_MIN] & 0x7f);
- tmp = ds1307->regs[DS1307_REG_HOUR] & 0x3f;
- t->tm_hour = bcd2bin(tmp);
- t->tm_wday = bcd2bin(ds1307->regs[DS1307_REG_WDAY] & 0x07) - 1;
- t->tm_mday = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
- tmp = ds1307->regs[DS1307_REG_MONTH] & 0x1f;
- t->tm_mon = bcd2bin(tmp) - 1;
- /* assume 20YY not 19YY, and ignore DS1337_BIT_CENTURY */
- t->tm_year = bcd2bin(ds1307->regs[DS1307_REG_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);
- /* initial clock setting can be undefined */
- return rtc_valid_tm(t);
- }
- static int ds1307_set_time(struct device *dev, struct rtc_time *t)
- {
- struct ds1307 *ds1307 = dev_get_drvdata(dev);
- int result;
- int tmp;
- u8 *buf = ds1307->regs;
- 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);
- buf[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
- buf[DS1307_REG_MIN] = bin2bcd(t->tm_min);
- buf[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
- buf[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
- buf[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
- buf[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
- /* assume 20YY not 19YY */
- tmp = t->tm_year - 100;
- buf[DS1307_REG_YEAR] = bin2bcd(tmp);
- switch (ds1307->type) {
- case ds_1337:
- case ds_1339:
- case ds_3231:
- buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
- break;
- case ds_1340:
- buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN
- | DS1340_BIT_CENTURY;
- break;
- case mcp794xx:
- /*
- * these bits were cleared when preparing the date/time
- * values and need to be set again before writing the
- * buffer out to the device.
- */
- buf[DS1307_REG_SECS] |= MCP794XX_BIT_ST;
- buf[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;
- break;
- default:
- break;
- }
- dev_dbg(dev, "%s: %7ph\n", "write", buf);
- result = ds1307->write_block_data(ds1307->client,
- ds1307->offset, 7, buf);
- if (result < 0) {
- 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 i2c_client *client = to_i2c_client(dev);
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- int ret;
- if (!test_bit(HAS_ALARM, &ds1307->flags))
- return -EINVAL;
- /* read all ALARM1, ALARM2, and status registers at once */
- ret = ds1307->read_block_data(client,
- DS1339_REG_ALARM1_SECS, 9, ds1307->regs);
- if (ret != 9) {
- dev_err(dev, "%s error %d\n", "alarm read", ret);
- return -EIO;
- }
- dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
- "alarm read",
- ds1307->regs[0], ds1307->regs[1],
- ds1307->regs[2], ds1307->regs[3],
- ds1307->regs[4], ds1307->regs[5],
- ds1307->regs[6], ds1307->regs[7],
- ds1307->regs[8]);
- /*
- * 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(ds1307->regs[0] & 0x7f);
- t->time.tm_min = bcd2bin(ds1307->regs[1] & 0x7f);
- t->time.tm_hour = bcd2bin(ds1307->regs[2] & 0x3f);
- t->time.tm_mday = bcd2bin(ds1307->regs[3] & 0x3f);
- t->time.tm_mon = -1;
- t->time.tm_year = -1;
- t->time.tm_wday = -1;
- t->time.tm_yday = -1;
- t->time.tm_isdst = -1;
- /* ... and status */
- t->enabled = !!(ds1307->regs[7] & DS1337_BIT_A1IE);
- t->pending = !!(ds1307->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 i2c_client *client = to_i2c_client(dev);
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- unsigned char *buf = ds1307->regs;
- u8 control, status;
- int ret;
- if (!test_bit(HAS_ALARM, &ds1307->flags))
- return -EINVAL;
- 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 = ds1307->read_block_data(client,
- DS1339_REG_ALARM1_SECS, 9, buf);
- if (ret != 9) {
- dev_err(dev, "%s error %d\n", "alarm write", ret);
- return -EIO;
- }
- control = ds1307->regs[7];
- status = ds1307->regs[8];
- dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
- "alarm set (old status)",
- ds1307->regs[0], ds1307->regs[1],
- ds1307->regs[2], ds1307->regs[3],
- ds1307->regs[4], ds1307->regs[5],
- ds1307->regs[6], control, status);
- /* set ALARM1, using 24 hour and day-of-month modes */
- buf[0] = bin2bcd(t->time.tm_sec);
- buf[1] = bin2bcd(t->time.tm_min);
- buf[2] = bin2bcd(t->time.tm_hour);
- buf[3] = bin2bcd(t->time.tm_mday);
- /* set ALARM2 to non-garbage */
- buf[4] = 0;
- buf[5] = 0;
- buf[6] = 0;
- /* optionally enable ALARM1 */
- buf[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
- if (t->enabled) {
- dev_dbg(dev, "alarm IRQ armed\n");
- buf[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
- }
- buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
- ret = ds1307->write_block_data(client,
- DS1339_REG_ALARM1_SECS, 9, buf);
- if (ret < 0) {
- dev_err(dev, "can't set alarm time\n");
- return ret;
- }
- return 0;
- }
- static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
- {
- struct i2c_client *client = to_i2c_client(dev);
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- int ret;
- if (!test_bit(HAS_ALARM, &ds1307->flags))
- return -ENOTTY;
- ret = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
- if (ret < 0)
- return ret;
- if (enabled)
- ret |= DS1337_BIT_A1IE;
- else
- ret &= ~DS1337_BIT_A1IE;
- ret = i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, ret);
- if (ret < 0)
- return ret;
- return 0;
- }
- 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,
- };
- /*----------------------------------------------------------------------*/
- /*
- * Alarm support for mcp794xx devices.
- */
- #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 (1 << 3)
- # define MCP794XX_BIT_ALMX_C0 (1 << 4)
- # define MCP794XX_BIT_ALMX_C1 (1 << 5)
- # define MCP794XX_BIT_ALMX_C2 (1 << 6)
- # define MCP794XX_BIT_ALMX_POL (1 << 7)
- # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \
- MCP794XX_BIT_ALMX_C1 | \
- MCP794XX_BIT_ALMX_C2)
- static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
- {
- struct i2c_client *client = dev_id;
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- struct mutex *lock = &ds1307->rtc->ops_lock;
- int reg, ret;
- mutex_lock(lock);
- /* Check and clear alarm 0 interrupt flag. */
- reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_ALARM0_CTRL);
- if (reg < 0)
- goto out;
- if (!(reg & MCP794XX_BIT_ALMX_IF))
- goto out;
- reg &= ~MCP794XX_BIT_ALMX_IF;
- ret = i2c_smbus_write_byte_data(client, MCP794XX_REG_ALARM0_CTRL, reg);
- if (ret < 0)
- goto out;
- /* Disable alarm 0. */
- reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_CONTROL);
- if (reg < 0)
- goto out;
- reg &= ~MCP794XX_BIT_ALM0_EN;
- ret = i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, reg);
- if (ret < 0)
- 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 i2c_client *client = to_i2c_client(dev);
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- u8 *regs = ds1307->regs;
- int ret;
- if (!test_bit(HAS_ALARM, &ds1307->flags))
- return -EINVAL;
- /* Read control and alarm 0 registers. */
- ret = ds1307->read_block_data(client, MCP794XX_REG_CONTROL, 10, regs);
- if (ret < 0)
- 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(ds1307->regs[3] & 0x7f);
- t->time.tm_min = bcd2bin(ds1307->regs[4] & 0x7f);
- t->time.tm_hour = bcd2bin(ds1307->regs[5] & 0x3f);
- t->time.tm_wday = bcd2bin(ds1307->regs[6] & 0x7) - 1;
- t->time.tm_mday = bcd2bin(ds1307->regs[7] & 0x3f);
- t->time.tm_mon = bcd2bin(ds1307->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=%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,
- !!(ds1307->regs[6] & MCP794XX_BIT_ALMX_POL),
- !!(ds1307->regs[6] & MCP794XX_BIT_ALMX_IF),
- (ds1307->regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);
- return 0;
- }
- static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)
- {
- struct i2c_client *client = to_i2c_client(dev);
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- unsigned char *regs = ds1307->regs;
- int ret;
- if (!test_bit(HAS_ALARM, &ds1307->flags))
- return -EINVAL;
- 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 = ds1307->read_block_data(client, MCP794XX_REG_CONTROL, 10, regs);
- if (ret < 0)
- 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] = bin2bcd(t->time.tm_wday + 1);
- 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 = ds1307->write_block_data(client, MCP794XX_REG_CONTROL, 10, regs);
- if (ret < 0)
- return ret;
- if (!t->enabled)
- return 0;
- regs[0] |= MCP794XX_BIT_ALM0_EN;
- return i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, regs[0]);
- }
- static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)
- {
- struct i2c_client *client = to_i2c_client(dev);
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- int reg;
- if (!test_bit(HAS_ALARM, &ds1307->flags))
- return -EINVAL;
- reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_CONTROL);
- if (reg < 0)
- return reg;
- if (enabled)
- reg |= MCP794XX_BIT_ALM0_EN;
- else
- reg &= ~MCP794XX_BIT_ALM0_EN;
- return i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, reg);
- }
- 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 ssize_t
- ds1307_nvram_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *attr,
- char *buf, loff_t off, size_t count)
- {
- struct i2c_client *client;
- struct ds1307 *ds1307;
- int result;
- client = kobj_to_i2c_client(kobj);
- ds1307 = i2c_get_clientdata(client);
- result = ds1307->read_block_data(client, ds1307->nvram_offset + off,
- count, buf);
- if (result < 0)
- dev_err(&client->dev, "%s error %d\n", "nvram read", result);
- return result;
- }
- static ssize_t
- ds1307_nvram_write(struct file *filp, struct kobject *kobj,
- struct bin_attribute *attr,
- char *buf, loff_t off, size_t count)
- {
- struct i2c_client *client;
- struct ds1307 *ds1307;
- int result;
- client = kobj_to_i2c_client(kobj);
- ds1307 = i2c_get_clientdata(client);
- result = ds1307->write_block_data(client, ds1307->nvram_offset + off,
- count, buf);
- if (result < 0) {
- dev_err(&client->dev, "%s error %d\n", "nvram write", result);
- return result;
- }
- return count;
- }
- /*----------------------------------------------------------------------*/
- static u8 do_trickle_setup_ds1339(struct i2c_client *client,
- uint32_t ohms, bool diode)
- {
- u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
- DS1307_TRICKLE_CHARGER_NO_DIODE;
- 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(&client->dev,
- "Unsupported ohm value %u in dt\n", ohms);
- return 0;
- }
- return setup;
- }
- static void ds1307_trickle_of_init(struct i2c_client *client,
- struct chip_desc *chip)
- {
- uint32_t ohms = 0;
- bool diode = true;
- if (!chip->do_trickle_setup)
- goto out;
- if (of_property_read_u32(client->dev.of_node, "trickle-resistor-ohms" , &ohms))
- goto out;
- if (of_property_read_bool(client->dev.of_node, "trickle-diode-disable"))
- diode = false;
- chip->trickle_charger_setup = chip->do_trickle_setup(client,
- ohms, diode);
- out:
- return;
- }
- static int ds1307_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
- {
- struct ds1307 *ds1307;
- int err = -ENODEV;
- int tmp;
- struct chip_desc *chip = &chips[id->driver_data];
- struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
- bool want_irq = false;
- unsigned char *buf;
- struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
- irq_handler_t irq_handler = ds1307_irq;
- static const int bbsqi_bitpos[] = {
- [ds_1337] = 0,
- [ds_1339] = DS1339_BIT_BBSQI,
- [ds_3231] = DS3231_BIT_BBSQW,
- };
- const struct rtc_class_ops *rtc_ops = &ds13xx_rtc_ops;
- if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)
- && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
- return -EIO;
- ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
- if (!ds1307)
- return -ENOMEM;
- i2c_set_clientdata(client, ds1307);
- ds1307->client = client;
- ds1307->type = id->driver_data;
- if (!pdata && client->dev.of_node)
- ds1307_trickle_of_init(client, chip);
- else if (pdata && pdata->trickle_charger_setup)
- chip->trickle_charger_setup = pdata->trickle_charger_setup;
- if (chip->trickle_charger_setup && chip->trickle_charger_reg) {
- dev_dbg(&client->dev, "writing trickle charger info 0x%x to 0x%x\n",
- DS13XX_TRICKLE_CHARGER_MAGIC | chip->trickle_charger_setup,
- chip->trickle_charger_reg);
- i2c_smbus_write_byte_data(client, chip->trickle_charger_reg,
- DS13XX_TRICKLE_CHARGER_MAGIC |
- chip->trickle_charger_setup);
- }
- buf = ds1307->regs;
- if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) {
- ds1307->read_block_data = ds1307_native_smbus_read_block_data;
- ds1307->write_block_data = ds1307_native_smbus_write_block_data;
- } else {
- ds1307->read_block_data = ds1307_read_block_data;
- ds1307->write_block_data = ds1307_write_block_data;
- }
- switch (ds1307->type) {
- case ds_1337:
- case ds_1339:
- case ds_3231:
- /* get registers that the "rtc" read below won't read... */
- tmp = ds1307->read_block_data(ds1307->client,
- DS1337_REG_CONTROL, 2, buf);
- if (tmp != 2) {
- dev_dbg(&client->dev, "read error %d\n", tmp);
- err = -EIO;
- goto exit;
- }
- /* oscillator off? turn it on, so clock can tick. */
- if (ds1307->regs[0] & DS1337_BIT_nEOSC)
- ds1307->regs[0] &= ~DS1337_BIT_nEOSC;
- /*
- * Using IRQ? Disable the square wave and both alarms.
- * For some variants, be sure alarms can trigger when we're
- * running on Vbackup (BBSQI/BBSQW)
- */
- if (ds1307->client->irq > 0 && chip->alarm) {
- ds1307->regs[0] |= DS1337_BIT_INTCN
- | bbsqi_bitpos[ds1307->type];
- ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
- want_irq = true;
- }
- i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL,
- ds1307->regs[0]);
- /* oscillator fault? clear flag, and warn */
- if (ds1307->regs[1] & DS1337_BIT_OSF) {
- i2c_smbus_write_byte_data(client, DS1337_REG_STATUS,
- ds1307->regs[1] & ~DS1337_BIT_OSF);
- dev_warn(&client->dev, "SET TIME!\n");
- }
- break;
- case rx_8025:
- tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
- RX8025_REG_CTRL1 << 4 | 0x08, 2, buf);
- if (tmp != 2) {
- dev_dbg(&client->dev, "read error %d\n", tmp);
- err = -EIO;
- goto exit;
- }
- /* oscillator off? turn it on, so clock can tick. */
- if (!(ds1307->regs[1] & RX8025_BIT_XST)) {
- ds1307->regs[1] |= RX8025_BIT_XST;
- i2c_smbus_write_byte_data(client,
- RX8025_REG_CTRL2 << 4 | 0x08,
- ds1307->regs[1]);
- dev_warn(&client->dev,
- "oscillator stop detected - SET TIME!\n");
- }
- if (ds1307->regs[1] & RX8025_BIT_PON) {
- ds1307->regs[1] &= ~RX8025_BIT_PON;
- i2c_smbus_write_byte_data(client,
- RX8025_REG_CTRL2 << 4 | 0x08,
- ds1307->regs[1]);
- dev_warn(&client->dev, "power-on detected\n");
- }
- if (ds1307->regs[1] & RX8025_BIT_VDET) {
- ds1307->regs[1] &= ~RX8025_BIT_VDET;
- i2c_smbus_write_byte_data(client,
- RX8025_REG_CTRL2 << 4 | 0x08,
- ds1307->regs[1]);
- dev_warn(&client->dev, "voltage drop detected\n");
- }
- /* make sure we are running in 24hour mode */
- if (!(ds1307->regs[0] & RX8025_BIT_2412)) {
- u8 hour;
- /* switch to 24 hour mode */
- i2c_smbus_write_byte_data(client,
- RX8025_REG_CTRL1 << 4 | 0x08,
- ds1307->regs[0] |
- RX8025_BIT_2412);
- tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
- RX8025_REG_CTRL1 << 4 | 0x08, 2, buf);
- if (tmp != 2) {
- dev_dbg(&client->dev, "read error %d\n", tmp);
- err = -EIO;
- goto exit;
- }
- /* correct hour */
- hour = bcd2bin(ds1307->regs[DS1307_REG_HOUR]);
- if (hour == 12)
- hour = 0;
- if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
- hour += 12;
- i2c_smbus_write_byte_data(client,
- DS1307_REG_HOUR << 4 | 0x08,
- hour);
- }
- break;
- case ds_1388:
- ds1307->offset = 1; /* Seconds starts at 1 */
- break;
- case mcp794xx:
- rtc_ops = &mcp794xx_rtc_ops;
- if (ds1307->client->irq > 0 && chip->alarm) {
- irq_handler = mcp794xx_irq;
- want_irq = true;
- }
- break;
- default:
- break;
- }
- read_rtc:
- /* read RTC registers */
- tmp = ds1307->read_block_data(ds1307->client, ds1307->offset, 8, buf);
- if (tmp != 8) {
- dev_dbg(&client->dev, "read error %d\n", tmp);
- err = -EIO;
- goto exit;
- }
- /*
- * minimal sanity checking; some chips (like DS1340) don't
- * specify the extra bits as must-be-zero, but there are
- * still a few values that are clearly out-of-range.
- */
- tmp = ds1307->regs[DS1307_REG_SECS];
- switch (ds1307->type) {
- case ds_1307:
- case m41t00:
- /* clock halted? turn it on, so clock can tick. */
- if (tmp & DS1307_BIT_CH) {
- i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
- dev_warn(&client->dev, "SET TIME!\n");
- goto read_rtc;
- }
- break;
- case ds_1338:
- /* clock halted? turn it on, so clock can tick. */
- if (tmp & DS1307_BIT_CH)
- i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
- /* oscillator fault? clear flag, and warn */
- if (ds1307->regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {
- i2c_smbus_write_byte_data(client, DS1307_REG_CONTROL,
- ds1307->regs[DS1307_REG_CONTROL]
- & ~DS1338_BIT_OSF);
- dev_warn(&client->dev, "SET TIME!\n");
- goto read_rtc;
- }
- break;
- case ds_1340:
- /* clock halted? turn it on, so clock can tick. */
- if (tmp & DS1340_BIT_nEOSC)
- i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
- tmp = i2c_smbus_read_byte_data(client, DS1340_REG_FLAG);
- if (tmp < 0) {
- dev_dbg(&client->dev, "read error %d\n", tmp);
- err = -EIO;
- goto exit;
- }
- /* oscillator fault? clear flag, and warn */
- if (tmp & DS1340_BIT_OSF) {
- i2c_smbus_write_byte_data(client, DS1340_REG_FLAG, 0);
- dev_warn(&client->dev, "SET TIME!\n");
- }
- break;
- case mcp794xx:
- /* make sure that the backup battery is enabled */
- if (!(ds1307->regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {
- i2c_smbus_write_byte_data(client, DS1307_REG_WDAY,
- ds1307->regs[DS1307_REG_WDAY]
- | MCP794XX_BIT_VBATEN);
- }
- /* clock halted? turn it on, so clock can tick. */
- if (!(tmp & MCP794XX_BIT_ST)) {
- i2c_smbus_write_byte_data(client, DS1307_REG_SECS,
- MCP794XX_BIT_ST);
- dev_warn(&client->dev, "SET TIME!\n");
- goto read_rtc;
- }
- break;
- default:
- break;
- }
- tmp = ds1307->regs[DS1307_REG_HOUR];
- switch (ds1307->type) {
- case ds_1340:
- case m41t00:
- /*
- * 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 (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
- tmp += 12;
- i2c_smbus_write_byte_data(client,
- ds1307->offset + DS1307_REG_HOUR,
- bin2bcd(tmp));
- }
- if (want_irq) {
- device_set_wakeup_capable(&client->dev, true);
- set_bit(HAS_ALARM, &ds1307->flags);
- }
- ds1307->rtc = devm_rtc_device_register(&client->dev, client->name,
- rtc_ops, THIS_MODULE);
- if (IS_ERR(ds1307->rtc)) {
- return PTR_ERR(ds1307->rtc);
- }
- if (want_irq) {
- err = devm_request_threaded_irq(&client->dev,
- client->irq, NULL, irq_handler,
- IRQF_SHARED | IRQF_ONESHOT,
- ds1307->rtc->name, client);
- if (err) {
- client->irq = 0;
- device_set_wakeup_capable(&client->dev, false);
- clear_bit(HAS_ALARM, &ds1307->flags);
- dev_err(&client->dev, "unable to request IRQ!\n");
- } else
- dev_dbg(&client->dev, "got IRQ %d\n", client->irq);
- }
- if (chip->nvram_size) {
- ds1307->nvram = devm_kzalloc(&client->dev,
- sizeof(struct bin_attribute),
- GFP_KERNEL);
- if (!ds1307->nvram) {
- dev_err(&client->dev, "cannot allocate memory for nvram sysfs\n");
- } else {
- ds1307->nvram->attr.name = "nvram";
- ds1307->nvram->attr.mode = S_IRUGO | S_IWUSR;
- sysfs_bin_attr_init(ds1307->nvram);
- ds1307->nvram->read = ds1307_nvram_read;
- ds1307->nvram->write = ds1307_nvram_write;
- ds1307->nvram->size = chip->nvram_size;
- ds1307->nvram_offset = chip->nvram_offset;
- err = sysfs_create_bin_file(&client->dev.kobj,
- ds1307->nvram);
- if (err) {
- dev_err(&client->dev,
- "unable to create sysfs file: %s\n",
- ds1307->nvram->attr.name);
- } else {
- set_bit(HAS_NVRAM, &ds1307->flags);
- dev_info(&client->dev, "%zu bytes nvram\n",
- ds1307->nvram->size);
- }
- }
- }
- return 0;
- exit:
- return err;
- }
- static int ds1307_remove(struct i2c_client *client)
- {
- struct ds1307 *ds1307 = i2c_get_clientdata(client);
- if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))
- sysfs_remove_bin_file(&client->dev.kobj, ds1307->nvram);
- return 0;
- }
- static struct i2c_driver ds1307_driver = {
- .driver = {
- .name = "rtc-ds1307",
- },
- .probe = ds1307_probe,
- .remove = ds1307_remove,
- .id_table = ds1307_id,
- };
- module_i2c_driver(ds1307_driver);
- MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
- MODULE_LICENSE("GPL");
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