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author | Kevin | 2014-11-15 09:58:27 +0800 |
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committer | Kevin | 2014-11-15 09:58:27 +0800 |
commit | 392e8802486cb573b916e746010e141a75f507e6 (patch) | |
tree | 50029aca02c81f087b90336e670b44e510782330 /ANDROID_3.4.5/drivers/rtc/rtc-pcf8563.c | |
download | FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.tar.gz FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.tar.bz2 FOSSEE-netbook-kernel-source-392e8802486cb573b916e746010e141a75f507e6.zip |
init android origin source code
Diffstat (limited to 'ANDROID_3.4.5/drivers/rtc/rtc-pcf8563.c')
-rw-r--r-- | ANDROID_3.4.5/drivers/rtc/rtc-pcf8563.c | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/drivers/rtc/rtc-pcf8563.c b/ANDROID_3.4.5/drivers/rtc/rtc-pcf8563.c new file mode 100644 index 00000000..bc0677de --- /dev/null +++ b/ANDROID_3.4.5/drivers/rtc/rtc-pcf8563.c @@ -0,0 +1,260 @@ +/* + * An I2C driver for the Philips PCF8563 RTC + * Copyright 2005-06 Tower Technologies + * + * Author: Alessandro Zummo <a.zummo@towertech.it> + * Maintainers: http://www.nslu2-linux.org/ + * + * based on the other drivers in this same directory. + * + * http://www.semiconductors.philips.com/acrobat/datasheets/PCF8563-04.pdf + * + * 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/i2c.h> +#include <linux/bcd.h> +#include <linux/rtc.h> +#include <linux/slab.h> +#include <linux/module.h> + +#define DRV_VERSION "0.4.3" + +#define PCF8563_REG_ST1 0x00 /* status */ +#define PCF8563_REG_ST2 0x01 + +#define PCF8563_REG_SC 0x02 /* datetime */ +#define PCF8563_REG_MN 0x03 +#define PCF8563_REG_HR 0x04 +#define PCF8563_REG_DM 0x05 +#define PCF8563_REG_DW 0x06 +#define PCF8563_REG_MO 0x07 +#define PCF8563_REG_YR 0x08 + +#define PCF8563_REG_AMN 0x09 /* alarm */ +#define PCF8563_REG_AHR 0x0A +#define PCF8563_REG_ADM 0x0B +#define PCF8563_REG_ADW 0x0C + +#define PCF8563_REG_CLKO 0x0D /* clock out */ +#define PCF8563_REG_TMRC 0x0E /* timer control */ +#define PCF8563_REG_TMR 0x0F /* timer */ + +#define PCF8563_SC_LV 0x80 /* low voltage */ +#define PCF8563_MO_C 0x80 /* century */ + +static struct i2c_driver pcf8563_driver; + +struct pcf8563 { + struct rtc_device *rtc; + /* + * The meaning of MO_C bit varies by the chip type. + * From PCF8563 datasheet: this bit is toggled when the years + * register overflows from 99 to 00 + * 0 indicates the century is 20xx + * 1 indicates the century is 19xx + * From RTC8564 datasheet: this bit indicates change of + * century. When the year digit data overflows from 99 to 00, + * this bit is set. By presetting it to 0 while still in the + * 20th century, it will be set in year 2000, ... + * There seems no reliable way to know how the system use this + * bit. So let's do it heuristically, assuming we are live in + * 1970...2069. + */ + int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */ +}; + +/* + * In the routines that deal directly with the pcf8563 hardware, we use + * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. + */ +static int pcf8563_get_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + struct pcf8563 *pcf8563 = i2c_get_clientdata(client); + unsigned char buf[13] = { PCF8563_REG_ST1 }; + + struct i2c_msg msgs[] = { + { client->addr, 0, 1, buf }, /* setup read ptr */ + { client->addr, I2C_M_RD, 13, buf }, /* read status + date */ + }; + + /* read registers */ + if ((i2c_transfer(client->adapter, msgs, 2)) != 2) { + dev_err(&client->dev, "%s: read error\n", __func__); + return -EIO; + } + + if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) + dev_info(&client->dev, + "low voltage detected, date/time is not reliable.\n"); + + dev_dbg(&client->dev, + "%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, " + "mday=%02x, wday=%02x, mon=%02x, year=%02x\n", + __func__, + buf[0], buf[1], buf[2], buf[3], + buf[4], buf[5], buf[6], buf[7], + buf[8]); + + + tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F); + tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F); + tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */ + tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F); + tm->tm_wday = buf[PCF8563_REG_DW] & 0x07; + tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */ + tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]); + if (tm->tm_year < 70) + tm->tm_year += 100; /* assume we are in 1970...2069 */ + /* detect the polarity heuristically. see note above. */ + pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ? + (tm->tm_year >= 100) : (tm->tm_year < 100); + + dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " + "mday=%d, mon=%d, year=%d, wday=%d\n", + __func__, + tm->tm_sec, tm->tm_min, tm->tm_hour, + tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); + + /* the clock can give out invalid datetime, but we cannot return + * -EINVAL otherwise hwclock will refuse to set the time on bootup. + */ + if (rtc_valid_tm(tm) < 0) + dev_err(&client->dev, "retrieved date/time is not valid.\n"); + + return 0; +} + +static int pcf8563_set_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + struct pcf8563 *pcf8563 = i2c_get_clientdata(client); + int i, err; + unsigned char buf[9]; + + dev_dbg(&client->dev, "%s: secs=%d, mins=%d, hours=%d, " + "mday=%d, mon=%d, year=%d, wday=%d\n", + __func__, + tm->tm_sec, tm->tm_min, tm->tm_hour, + tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); + + /* hours, minutes and seconds */ + buf[PCF8563_REG_SC] = bin2bcd(tm->tm_sec); + buf[PCF8563_REG_MN] = bin2bcd(tm->tm_min); + buf[PCF8563_REG_HR] = bin2bcd(tm->tm_hour); + + buf[PCF8563_REG_DM] = bin2bcd(tm->tm_mday); + + /* month, 1 - 12 */ + buf[PCF8563_REG_MO] = bin2bcd(tm->tm_mon + 1); + + /* year and century */ + buf[PCF8563_REG_YR] = bin2bcd(tm->tm_year % 100); + if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100)) + buf[PCF8563_REG_MO] |= PCF8563_MO_C; + + buf[PCF8563_REG_DW] = tm->tm_wday & 0x07; + + /* write register's data */ + for (i = 0; i < 7; i++) { + unsigned char data[2] = { PCF8563_REG_SC + i, + buf[PCF8563_REG_SC + i] }; + + err = i2c_master_send(client, data, sizeof(data)); + if (err != sizeof(data)) { + dev_err(&client->dev, + "%s: err=%d addr=%02x, data=%02x\n", + __func__, err, data[0], data[1]); + return -EIO; + } + }; + + return 0; +} + +static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + return pcf8563_get_datetime(to_i2c_client(dev), tm); +} + +static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + return pcf8563_set_datetime(to_i2c_client(dev), tm); +} + +static const struct rtc_class_ops pcf8563_rtc_ops = { + .read_time = pcf8563_rtc_read_time, + .set_time = pcf8563_rtc_set_time, +}; + +static int pcf8563_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct pcf8563 *pcf8563; + + int err = 0; + + dev_dbg(&client->dev, "%s\n", __func__); + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + pcf8563 = kzalloc(sizeof(struct pcf8563), GFP_KERNEL); + if (!pcf8563) + return -ENOMEM; + + dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); + + i2c_set_clientdata(client, pcf8563); + + pcf8563->rtc = rtc_device_register(pcf8563_driver.driver.name, + &client->dev, &pcf8563_rtc_ops, THIS_MODULE); + + if (IS_ERR(pcf8563->rtc)) { + err = PTR_ERR(pcf8563->rtc); + goto exit_kfree; + } + + return 0; + +exit_kfree: + kfree(pcf8563); + + return err; +} + +static int pcf8563_remove(struct i2c_client *client) +{ + struct pcf8563 *pcf8563 = i2c_get_clientdata(client); + + if (pcf8563->rtc) + rtc_device_unregister(pcf8563->rtc); + + kfree(pcf8563); + + return 0; +} + +static const struct i2c_device_id pcf8563_id[] = { + { "pcf8563", 0 }, + { "rtc8564", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pcf8563_id); + +static struct i2c_driver pcf8563_driver = { + .driver = { + .name = "rtc-pcf8563", + }, + .probe = pcf8563_probe, + .remove = pcf8563_remove, + .id_table = pcf8563_id, +}; + +module_i2c_driver(pcf8563_driver); + +MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); +MODULE_DESCRIPTION("Philips PCF8563/Epson RTC8564 RTC driver"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRV_VERSION); |