838 lines
21 KiB
C
838 lines
21 KiB
C
/*
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* rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips.
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*
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* Copyright (C) 2005 James Chapman (ds1337 core)
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* Copyright (C) 2006 David Brownell
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/i2c.h>
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#include <linux/string.h>
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#include <linux/rtc.h>
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#include <linux/bcd.h>
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/* We can't determine type by probing, but if we expect pre-Linux code
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* to have set the chip up as a clock (turning on the oscillator and
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* setting the date and time), Linux can ignore the non-clock features.
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* That's a natural job for a factory or repair bench.
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*/
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enum ds_type {
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ds_1307,
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ds_1337,
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ds_1338,
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ds_1339,
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ds_1340,
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m41t00,
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// rs5c372 too? different address...
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};
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/* RTC registers don't differ much, except for the century flag */
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#define DS1307_REG_SECS 0x00 /* 00-59 */
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# define DS1307_BIT_CH 0x80
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# define DS1340_BIT_nEOSC 0x80
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#define DS1307_REG_MIN 0x01 /* 00-59 */
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#define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
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# define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
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# define DS1307_BIT_PM 0x20 /* in REG_HOUR */
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# define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
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# define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
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#define DS1307_REG_WDAY 0x03 /* 01-07 */
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#define DS1307_REG_MDAY 0x04 /* 01-31 */
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#define DS1307_REG_MONTH 0x05 /* 01-12 */
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# define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */
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#define DS1307_REG_YEAR 0x06 /* 00-99 */
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/* Other registers (control, status, alarms, trickle charge, NVRAM, etc)
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* start at 7, and they differ a LOT. Only control and status matter for
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* basic RTC date and time functionality; be careful using them.
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*/
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#define DS1307_REG_CONTROL 0x07 /* or ds1338 */
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# define DS1307_BIT_OUT 0x80
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# define DS1338_BIT_OSF 0x20
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# define DS1307_BIT_SQWE 0x10
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# define DS1307_BIT_RS1 0x02
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# define DS1307_BIT_RS0 0x01
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#define DS1337_REG_CONTROL 0x0e
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# define DS1337_BIT_nEOSC 0x80
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# define DS1339_BIT_BBSQI 0x20
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# define DS1337_BIT_RS2 0x10
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# define DS1337_BIT_RS1 0x08
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# define DS1337_BIT_INTCN 0x04
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# define DS1337_BIT_A2IE 0x02
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# define DS1337_BIT_A1IE 0x01
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#define DS1340_REG_CONTROL 0x07
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# define DS1340_BIT_OUT 0x80
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# define DS1340_BIT_FT 0x40
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# define DS1340_BIT_CALIB_SIGN 0x20
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# define DS1340_M_CALIBRATION 0x1f
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#define DS1340_REG_FLAG 0x09
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# define DS1340_BIT_OSF 0x80
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#define DS1337_REG_STATUS 0x0f
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# define DS1337_BIT_OSF 0x80
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# define DS1337_BIT_A2I 0x02
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# define DS1337_BIT_A1I 0x01
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#define DS1339_REG_ALARM1_SECS 0x07
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#define DS1339_REG_TRICKLE 0x10
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struct ds1307 {
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u8 reg_addr;
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u8 regs[11];
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enum ds_type type;
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unsigned long flags;
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#define HAS_NVRAM 0 /* bit 0 == sysfs file active */
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#define HAS_ALARM 1 /* bit 1 == irq claimed */
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struct i2c_msg msg[2];
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struct i2c_client *client;
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struct rtc_device *rtc;
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struct work_struct work;
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};
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struct chip_desc {
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unsigned nvram56:1;
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unsigned alarm:1;
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};
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static const struct chip_desc chips[] = {
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[ds_1307] = {
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.nvram56 = 1,
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},
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[ds_1337] = {
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.alarm = 1,
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},
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[ds_1338] = {
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.nvram56 = 1,
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},
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[ds_1339] = {
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.alarm = 1,
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},
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[ds_1340] = {
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},
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[m41t00] = {
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}, };
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static const struct i2c_device_id ds1307_id[] = {
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{ "ds1307", ds_1307 },
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{ "ds1337", ds_1337 },
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{ "ds1338", ds_1338 },
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{ "ds1339", ds_1339 },
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{ "ds1340", ds_1340 },
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{ "m41t00", m41t00 },
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{ }
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};
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MODULE_DEVICE_TABLE(i2c, ds1307_id);
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/*----------------------------------------------------------------------*/
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/*
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* The IRQ logic includes a "real" handler running in IRQ context just
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* long enough to schedule this workqueue entry. We need a task context
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* to talk to the RTC, since I2C I/O calls require that; and disable the
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* IRQ until we clear its status on the chip, so that this handler can
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* work with any type of triggering (not just falling edge).
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*
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* The ds1337 and ds1339 both have two alarms, but we only use the first
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* one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
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* signal; ds1339 chips have only one alarm signal.
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*/
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static void ds1307_work(struct work_struct *work)
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{
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struct ds1307 *ds1307;
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struct i2c_client *client;
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struct mutex *lock;
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int stat, control;
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ds1307 = container_of(work, struct ds1307, work);
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client = ds1307->client;
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lock = &ds1307->rtc->ops_lock;
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mutex_lock(lock);
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stat = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS);
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if (stat < 0)
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goto out;
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if (stat & DS1337_BIT_A1I) {
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stat &= ~DS1337_BIT_A1I;
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i2c_smbus_write_byte_data(client, DS1337_REG_STATUS, stat);
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control = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
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if (control < 0)
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goto out;
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control &= ~DS1337_BIT_A1IE;
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i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, control);
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/* rtc_update_irq() assumes that it is called
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* from IRQ-disabled context.
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*/
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local_irq_disable();
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rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
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local_irq_enable();
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}
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out:
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if (test_bit(HAS_ALARM, &ds1307->flags))
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enable_irq(client->irq);
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mutex_unlock(lock);
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}
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static irqreturn_t ds1307_irq(int irq, void *dev_id)
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{
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struct i2c_client *client = dev_id;
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struct ds1307 *ds1307 = i2c_get_clientdata(client);
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disable_irq_nosync(irq);
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schedule_work(&ds1307->work);
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return IRQ_HANDLED;
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}
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/*----------------------------------------------------------------------*/
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static int ds1307_get_time(struct device *dev, struct rtc_time *t)
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{
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struct ds1307 *ds1307 = dev_get_drvdata(dev);
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int tmp;
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/* read the RTC date and time registers all at once */
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ds1307->reg_addr = 0;
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ds1307->msg[1].flags = I2C_M_RD;
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ds1307->msg[1].len = 7;
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tmp = i2c_transfer(to_i2c_adapter(ds1307->client->dev.parent),
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ds1307->msg, 2);
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if (tmp != 2) {
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dev_err(dev, "%s error %d\n", "read", tmp);
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return -EIO;
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}
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dev_dbg(dev, "%s: %02x %02x %02x %02x %02x %02x %02x\n",
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"read",
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ds1307->regs[0], ds1307->regs[1],
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ds1307->regs[2], ds1307->regs[3],
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ds1307->regs[4], ds1307->regs[5],
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ds1307->regs[6]);
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t->tm_sec = bcd2bin(ds1307->regs[DS1307_REG_SECS] & 0x7f);
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t->tm_min = bcd2bin(ds1307->regs[DS1307_REG_MIN] & 0x7f);
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tmp = ds1307->regs[DS1307_REG_HOUR] & 0x3f;
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t->tm_hour = bcd2bin(tmp);
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t->tm_wday = bcd2bin(ds1307->regs[DS1307_REG_WDAY] & 0x07) - 1;
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t->tm_mday = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
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tmp = ds1307->regs[DS1307_REG_MONTH] & 0x1f;
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t->tm_mon = bcd2bin(tmp) - 1;
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/* assume 20YY not 19YY, and ignore DS1337_BIT_CENTURY */
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t->tm_year = bcd2bin(ds1307->regs[DS1307_REG_YEAR]) + 100;
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dev_dbg(dev, "%s secs=%d, mins=%d, "
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"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
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"read", t->tm_sec, t->tm_min,
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t->tm_hour, t->tm_mday,
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t->tm_mon, t->tm_year, t->tm_wday);
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/* initial clock setting can be undefined */
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return rtc_valid_tm(t);
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}
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static int ds1307_set_time(struct device *dev, struct rtc_time *t)
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{
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struct ds1307 *ds1307 = dev_get_drvdata(dev);
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int result;
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int tmp;
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u8 *buf = ds1307->regs;
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dev_dbg(dev, "%s secs=%d, mins=%d, "
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"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
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"write", t->tm_sec, t->tm_min,
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t->tm_hour, t->tm_mday,
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t->tm_mon, t->tm_year, t->tm_wday);
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*buf++ = 0; /* first register addr */
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buf[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
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buf[DS1307_REG_MIN] = bin2bcd(t->tm_min);
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buf[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
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buf[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
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buf[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
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buf[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
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/* assume 20YY not 19YY */
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tmp = t->tm_year - 100;
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buf[DS1307_REG_YEAR] = bin2bcd(tmp);
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switch (ds1307->type) {
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case ds_1337:
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case ds_1339:
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buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
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break;
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case ds_1340:
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buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN
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| DS1340_BIT_CENTURY;
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break;
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default:
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break;
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}
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ds1307->msg[1].flags = 0;
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ds1307->msg[1].len = 8;
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dev_dbg(dev, "%s: %02x %02x %02x %02x %02x %02x %02x\n",
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"write", buf[0], buf[1], buf[2], buf[3],
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buf[4], buf[5], buf[6]);
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result = i2c_transfer(to_i2c_adapter(ds1307->client->dev.parent),
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&ds1307->msg[1], 1);
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if (result != 1) {
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dev_err(dev, "%s error %d\n", "write", tmp);
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return -EIO;
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}
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return 0;
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}
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static int ds1307_read_alarm(struct device *dev, struct rtc_wkalrm *t)
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{
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struct i2c_client *client = to_i2c_client(dev);
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struct ds1307 *ds1307 = i2c_get_clientdata(client);
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int ret;
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if (!test_bit(HAS_ALARM, &ds1307->flags))
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return -EINVAL;
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/* read all ALARM1, ALARM2, and status registers at once */
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ds1307->reg_addr = DS1339_REG_ALARM1_SECS;
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ds1307->msg[1].flags = I2C_M_RD;
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ds1307->msg[1].len = 9;
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ret = i2c_transfer(to_i2c_adapter(client->dev.parent),
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ds1307->msg, 2);
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if (ret != 2) {
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dev_err(dev, "%s error %d\n", "alarm read", ret);
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return -EIO;
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}
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dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
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"alarm read",
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ds1307->regs[0], ds1307->regs[1],
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ds1307->regs[2], ds1307->regs[3],
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ds1307->regs[4], ds1307->regs[5],
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ds1307->regs[6], ds1307->regs[7],
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ds1307->regs[8]);
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/* report alarm time (ALARM1); assume 24 hour and day-of-month modes,
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* and that all four fields are checked matches
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*/
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t->time.tm_sec = bcd2bin(ds1307->regs[0] & 0x7f);
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t->time.tm_min = bcd2bin(ds1307->regs[1] & 0x7f);
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t->time.tm_hour = bcd2bin(ds1307->regs[2] & 0x3f);
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t->time.tm_mday = bcd2bin(ds1307->regs[3] & 0x3f);
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t->time.tm_mon = -1;
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t->time.tm_year = -1;
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t->time.tm_wday = -1;
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t->time.tm_yday = -1;
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t->time.tm_isdst = -1;
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/* ... and status */
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t->enabled = !!(ds1307->regs[7] & DS1337_BIT_A1IE);
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t->pending = !!(ds1307->regs[8] & DS1337_BIT_A1I);
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dev_dbg(dev, "%s secs=%d, mins=%d, "
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"hours=%d, mday=%d, enabled=%d, pending=%d\n",
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"alarm read", t->time.tm_sec, t->time.tm_min,
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t->time.tm_hour, t->time.tm_mday,
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t->enabled, t->pending);
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return 0;
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}
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static int ds1307_set_alarm(struct device *dev, struct rtc_wkalrm *t)
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{
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struct i2c_client *client = to_i2c_client(dev);
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struct ds1307 *ds1307 = i2c_get_clientdata(client);
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unsigned char *buf = ds1307->regs;
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u8 control, status;
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int ret;
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if (!test_bit(HAS_ALARM, &ds1307->flags))
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return -EINVAL;
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dev_dbg(dev, "%s secs=%d, mins=%d, "
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"hours=%d, mday=%d, enabled=%d, pending=%d\n",
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"alarm set", t->time.tm_sec, t->time.tm_min,
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t->time.tm_hour, t->time.tm_mday,
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t->enabled, t->pending);
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/* read current status of both alarms and the chip */
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ds1307->reg_addr = DS1339_REG_ALARM1_SECS;
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ds1307->msg[1].flags = I2C_M_RD;
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ds1307->msg[1].len = 9;
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ret = i2c_transfer(to_i2c_adapter(client->dev.parent),
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ds1307->msg, 2);
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if (ret != 2) {
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dev_err(dev, "%s error %d\n", "alarm write", ret);
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return -EIO;
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}
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control = ds1307->regs[7];
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status = ds1307->regs[8];
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dev_dbg(dev, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
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"alarm set (old status)",
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ds1307->regs[0], ds1307->regs[1],
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ds1307->regs[2], ds1307->regs[3],
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ds1307->regs[4], ds1307->regs[5],
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ds1307->regs[6], control, status);
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/* set ALARM1, using 24 hour and day-of-month modes */
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*buf++ = DS1339_REG_ALARM1_SECS; /* first register addr */
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buf[0] = bin2bcd(t->time.tm_sec);
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buf[1] = bin2bcd(t->time.tm_min);
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buf[2] = bin2bcd(t->time.tm_hour);
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buf[3] = bin2bcd(t->time.tm_mday);
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/* set ALARM2 to non-garbage */
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buf[4] = 0;
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buf[5] = 0;
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buf[6] = 0;
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/* optionally enable ALARM1 */
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buf[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
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if (t->enabled) {
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dev_dbg(dev, "alarm IRQ armed\n");
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buf[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
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}
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buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
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ds1307->msg[1].flags = 0;
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ds1307->msg[1].len = 10;
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ret = i2c_transfer(to_i2c_adapter(client->dev.parent),
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&ds1307->msg[1], 1);
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if (ret != 1) {
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dev_err(dev, "can't set alarm time\n");
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return -EIO;
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}
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return 0;
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}
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static int ds1307_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
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{
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struct i2c_client *client = to_i2c_client(dev);
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struct ds1307 *ds1307 = i2c_get_clientdata(client);
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int ret;
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switch (cmd) {
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case RTC_AIE_OFF:
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if (!test_bit(HAS_ALARM, &ds1307->flags))
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return -ENOTTY;
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ret = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
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if (ret < 0)
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return ret;
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ret &= ~DS1337_BIT_A1IE;
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ret = i2c_smbus_write_byte_data(client,
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DS1337_REG_CONTROL, ret);
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if (ret < 0)
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return ret;
|
|
|
|
break;
|
|
|
|
case RTC_AIE_ON:
|
|
if (!test_bit(HAS_ALARM, &ds1307->flags))
|
|
return -ENOTTY;
|
|
|
|
ret = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret |= DS1337_BIT_A1IE;
|
|
|
|
ret = i2c_smbus_write_byte_data(client,
|
|
DS1337_REG_CONTROL, ret);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
break;
|
|
|
|
default:
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct rtc_class_ops ds13xx_rtc_ops = {
|
|
.read_time = ds1307_get_time,
|
|
.set_time = ds1307_set_time,
|
|
.read_alarm = ds1307_read_alarm,
|
|
.set_alarm = ds1307_set_alarm,
|
|
.ioctl = ds1307_ioctl,
|
|
};
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
#define NVRAM_SIZE 56
|
|
|
|
static ssize_t
|
|
ds1307_nvram_read(struct kobject *kobj, struct bin_attribute *attr,
|
|
char *buf, loff_t off, size_t count)
|
|
{
|
|
struct i2c_client *client;
|
|
struct ds1307 *ds1307;
|
|
struct i2c_msg msg[2];
|
|
int result;
|
|
|
|
client = kobj_to_i2c_client(kobj);
|
|
ds1307 = i2c_get_clientdata(client);
|
|
|
|
if (unlikely(off >= NVRAM_SIZE))
|
|
return 0;
|
|
if ((off + count) > NVRAM_SIZE)
|
|
count = NVRAM_SIZE - off;
|
|
if (unlikely(!count))
|
|
return count;
|
|
|
|
msg[0].addr = client->addr;
|
|
msg[0].flags = 0;
|
|
msg[0].len = 1;
|
|
msg[0].buf = buf;
|
|
|
|
buf[0] = 8 + off;
|
|
|
|
msg[1].addr = client->addr;
|
|
msg[1].flags = I2C_M_RD;
|
|
msg[1].len = count;
|
|
msg[1].buf = buf;
|
|
|
|
result = i2c_transfer(to_i2c_adapter(client->dev.parent), msg, 2);
|
|
if (result != 2) {
|
|
dev_err(&client->dev, "%s error %d\n", "nvram read", result);
|
|
return -EIO;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static ssize_t
|
|
ds1307_nvram_write(struct kobject *kobj, struct bin_attribute *attr,
|
|
char *buf, loff_t off, size_t count)
|
|
{
|
|
struct i2c_client *client;
|
|
u8 buffer[NVRAM_SIZE + 1];
|
|
int ret;
|
|
|
|
client = kobj_to_i2c_client(kobj);
|
|
|
|
if (unlikely(off >= NVRAM_SIZE))
|
|
return -EFBIG;
|
|
if ((off + count) > NVRAM_SIZE)
|
|
count = NVRAM_SIZE - off;
|
|
if (unlikely(!count))
|
|
return count;
|
|
|
|
buffer[0] = 8 + off;
|
|
memcpy(buffer + 1, buf, count);
|
|
|
|
ret = i2c_master_send(client, buffer, count + 1);
|
|
return (ret < 0) ? ret : (ret - 1);
|
|
}
|
|
|
|
static struct bin_attribute nvram = {
|
|
.attr = {
|
|
.name = "nvram",
|
|
.mode = S_IRUGO | S_IWUSR,
|
|
},
|
|
|
|
.read = ds1307_nvram_read,
|
|
.write = ds1307_nvram_write,
|
|
.size = NVRAM_SIZE,
|
|
};
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
static struct i2c_driver ds1307_driver;
|
|
|
|
static int __devinit ds1307_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct ds1307 *ds1307;
|
|
int err = -ENODEV;
|
|
int tmp;
|
|
const struct chip_desc *chip = &chips[id->driver_data];
|
|
struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
|
|
int want_irq = false;
|
|
|
|
if (!i2c_check_functionality(adapter,
|
|
I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
|
|
return -EIO;
|
|
|
|
if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL)))
|
|
return -ENOMEM;
|
|
|
|
ds1307->client = client;
|
|
i2c_set_clientdata(client, ds1307);
|
|
|
|
ds1307->msg[0].addr = client->addr;
|
|
ds1307->msg[0].flags = 0;
|
|
ds1307->msg[0].len = 1;
|
|
ds1307->msg[0].buf = &ds1307->reg_addr;
|
|
|
|
ds1307->msg[1].addr = client->addr;
|
|
ds1307->msg[1].flags = I2C_M_RD;
|
|
ds1307->msg[1].len = sizeof(ds1307->regs);
|
|
ds1307->msg[1].buf = ds1307->regs;
|
|
|
|
ds1307->type = id->driver_data;
|
|
|
|
switch (ds1307->type) {
|
|
case ds_1337:
|
|
case ds_1339:
|
|
/* has IRQ? */
|
|
if (ds1307->client->irq > 0 && chip->alarm) {
|
|
INIT_WORK(&ds1307->work, ds1307_work);
|
|
want_irq = true;
|
|
}
|
|
|
|
ds1307->reg_addr = DS1337_REG_CONTROL;
|
|
ds1307->msg[1].len = 2;
|
|
|
|
/* get registers that the "rtc" read below won't read... */
|
|
tmp = i2c_transfer(adapter, ds1307->msg, 2);
|
|
if (tmp != 2) {
|
|
pr_debug("read error %d\n", tmp);
|
|
err = -EIO;
|
|
goto exit_free;
|
|
}
|
|
|
|
ds1307->reg_addr = 0;
|
|
ds1307->msg[1].len = sizeof(ds1307->regs);
|
|
|
|
/* 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 ds1339, be sure alarms can trigger when we're
|
|
* running on Vbackup (BBSQI); we assume ds1337 will
|
|
* ignore that bit
|
|
*/
|
|
if (want_irq) {
|
|
ds1307->regs[0] |= DS1337_BIT_INTCN | DS1339_BIT_BBSQI;
|
|
ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
|
|
}
|
|
|
|
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;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
read_rtc:
|
|
/* read RTC registers */
|
|
|
|
tmp = i2c_transfer(adapter, ds1307->msg, 2);
|
|
if (tmp != 2) {
|
|
pr_debug("read error %d\n", tmp);
|
|
err = -EIO;
|
|
goto exit_free;
|
|
}
|
|
|
|
/* 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) {
|
|
pr_debug("read error %d\n", tmp);
|
|
err = -EIO;
|
|
goto exit_free;
|
|
}
|
|
|
|
/* 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 ds_1337:
|
|
case ds_1339:
|
|
break;
|
|
}
|
|
|
|
tmp = ds1307->regs[DS1307_REG_SECS];
|
|
tmp = bcd2bin(tmp & 0x7f);
|
|
if (tmp > 60)
|
|
goto exit_bad;
|
|
tmp = bcd2bin(ds1307->regs[DS1307_REG_MIN] & 0x7f);
|
|
if (tmp > 60)
|
|
goto exit_bad;
|
|
|
|
tmp = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
|
|
if (tmp == 0 || tmp > 31)
|
|
goto exit_bad;
|
|
|
|
tmp = bcd2bin(ds1307->regs[DS1307_REG_MONTH] & 0x1f);
|
|
if (tmp == 0 || tmp > 12)
|
|
goto exit_bad;
|
|
|
|
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;
|
|
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_REG_HOUR,
|
|
bin2bcd(tmp));
|
|
}
|
|
|
|
ds1307->rtc = rtc_device_register(client->name, &client->dev,
|
|
&ds13xx_rtc_ops, THIS_MODULE);
|
|
if (IS_ERR(ds1307->rtc)) {
|
|
err = PTR_ERR(ds1307->rtc);
|
|
dev_err(&client->dev,
|
|
"unable to register the class device\n");
|
|
goto exit_free;
|
|
}
|
|
|
|
if (want_irq) {
|
|
err = request_irq(client->irq, ds1307_irq, 0,
|
|
ds1307->rtc->name, client);
|
|
if (err) {
|
|
dev_err(&client->dev,
|
|
"unable to request IRQ!\n");
|
|
goto exit_irq;
|
|
}
|
|
set_bit(HAS_ALARM, &ds1307->flags);
|
|
dev_dbg(&client->dev, "got IRQ %d\n", client->irq);
|
|
}
|
|
|
|
if (chip->nvram56) {
|
|
err = sysfs_create_bin_file(&client->dev.kobj, &nvram);
|
|
if (err == 0) {
|
|
set_bit(HAS_NVRAM, &ds1307->flags);
|
|
dev_info(&client->dev, "56 bytes nvram\n");
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
|
|
exit_bad:
|
|
dev_dbg(&client->dev, "%s: %02x %02x %02x %02x %02x %02x %02x\n",
|
|
"bogus register",
|
|
ds1307->regs[0], ds1307->regs[1],
|
|
ds1307->regs[2], ds1307->regs[3],
|
|
ds1307->regs[4], ds1307->regs[5],
|
|
ds1307->regs[6]);
|
|
exit_irq:
|
|
if (ds1307->rtc)
|
|
rtc_device_unregister(ds1307->rtc);
|
|
exit_free:
|
|
kfree(ds1307);
|
|
return err;
|
|
}
|
|
|
|
static int __devexit ds1307_remove(struct i2c_client *client)
|
|
{
|
|
struct ds1307 *ds1307 = i2c_get_clientdata(client);
|
|
|
|
if (test_and_clear_bit(HAS_ALARM, &ds1307->flags)) {
|
|
free_irq(client->irq, client);
|
|
cancel_work_sync(&ds1307->work);
|
|
}
|
|
|
|
if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))
|
|
sysfs_remove_bin_file(&client->dev.kobj, &nvram);
|
|
|
|
rtc_device_unregister(ds1307->rtc);
|
|
kfree(ds1307);
|
|
return 0;
|
|
}
|
|
|
|
static struct i2c_driver ds1307_driver = {
|
|
.driver = {
|
|
.name = "rtc-ds1307",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = ds1307_probe,
|
|
.remove = __devexit_p(ds1307_remove),
|
|
.id_table = ds1307_id,
|
|
};
|
|
|
|
static int __init ds1307_init(void)
|
|
{
|
|
return i2c_add_driver(&ds1307_driver);
|
|
}
|
|
module_init(ds1307_init);
|
|
|
|
static void __exit ds1307_exit(void)
|
|
{
|
|
i2c_del_driver(&ds1307_driver);
|
|
}
|
|
module_exit(ds1307_exit);
|
|
|
|
MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
|
|
MODULE_LICENSE("GPL");
|