diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index e187887..87da366 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -264,6 +264,17 @@ config RTC_DRV_PCF8583 This driver can also be built as a module. If so, the module will be called rtc-pcf8583. +config RTC_DRV_PCF2127A + tristate "Philips PCF2127A (only I2C)" + help + If you say yes here you get support for the Philips PCF2127A + RTC. This driver implements only the i2c-interface to the chip. + It maybe work with other pcf2127, but's tested only against + the pcf2127a. + + This driver can also be built as a module. If so, the module + will be called rtc-pcf2127a. + config RTC_DRV_M41T80 tristate "ST M41T62/65/M41T80/81/82/83/84/85/87" help diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index ca91c3c..b77b577 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -70,6 +70,7 @@ obj-$(CONFIG_RTC_DRV_OMAP) += rtc-omap.o obj-$(CONFIG_RTC_DRV_PCAP) += rtc-pcap.o obj-$(CONFIG_RTC_DRV_PCF8563) += rtc-pcf8563.o obj-$(CONFIG_RTC_DRV_PCF8583) += rtc-pcf8583.o +obj-$(CONFIG_RTC_DRV_PCF2127A) += rtc-pcf2127a.o obj-$(CONFIG_RTC_DRV_PCF2123) += rtc-pcf2123.o obj-$(CONFIG_RTC_DRV_PCF50633) += rtc-pcf50633.o obj-$(CONFIG_RTC_DRV_PL030) += rtc-pl030.o diff --git a/drivers/rtc/rtc-pcf2127a.c b/drivers/rtc/rtc-pcf2127a.c new file mode 100644 index 0000000..7822036 --- /dev/null +++ b/drivers/rtc/rtc-pcf2127a.c @@ -0,0 +1,344 @@ +/* + * Driver the the NXP/Philips PCF2127A RTC (only I2C) + * + * Copyright (c) 2011 ECKELMANN AG. + * + * Authors: Matthias Wolf + * Torsten Mehnert + * + * RTC-Datasheet: http://www.nxp.com/documents/data_sheet/PCF2127A.pdf + * + * NOTE: This driver only implements the i2c-interface to the RTC. + * This driver is based on rtc-pcf8363 from Alessandro Zummo. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include + +#define DRV_VERSION "0.1.0" + +/* PCF2127A Registers */ +#define PCF2127A_REG_CTL1 0x00 /* Control 1 */ +#define PCF2127A_REG_CTL2 0x01 /* Control 2 */ +#define PCF2127A_REG_CTL3 0x02 /* Control 3 */ + +#define PCF2127A_REG_SC 0x03 /* second value */ +#define PCF2127A_REG_MN 0x04 /* minute value */ +#define PCF2127A_REG_HR 0x05 /* hour value */ +#define PCF2127A_REG_DM 0x06 /* day value */ +#define PCF2127A_REG_DW 0x07 /* weekday value */ +#define PCF2127A_REG_MO 0x08 /* month value */ +#define PCF2127A_REG_YR 0x09 /* year value */ + +#define PCF2127A_REG_SC_ALARM 0x0A /* second alarm */ +#define PCF2127A_REG_MN_ALARM 0x0B /* minute alarm */ +#define PCF2127A_REG_HR_ALARM 0x0C /* hour alarm */ +#define PCF2127A_REG_DM_ALARM 0x0D /* day alarm */ +#define PCF2127A_REG_DW_ALARM 0x0E /* weekday alarm */ + +#define PCF2127A_REG_CLKO 0x0F /* clock out */ +#define PCF2127A_REG_WD_TMRC 0x10 /* watchdog timer control */ +#define PCF2127A_REG_WD_TMVAL 0x11 /* watchdog timer value */ + +#define PCF2127A_REG_TSCTL 0x12 /* timestamp control */ +#define PCF2127A_REG_SC_TS 0x13 /* second timestamp */ +#define PCF2127A_REG_MN_TS 0x14 /* minute timestamp */ +#define PCF2127A_REG_HR_TS 0x15 /* hour timestamp */ +#define PCF2127A_REG_DM_TS 0x16 /* day timestamp */ +#define PCF2127A_REG_MO_TS 0x17 /* month timestamp */ +#define PCF2127A_REG_YR_TS 0x18 /* year timestamp */ +#define PCF2127A_REG_AGI_OFF 0x19 /* aging offset */ +#define PCF2127A_REG_RAM_MSB 0x1A /* RAM address MSB */ +#define PCF2127A_REG_RAM_LSB 0x1B /* RAM address LSB */ +#define PCF2127A_REG_RAM_WCMD 0x1C /* RAM write command */ +#define PCF2127A_REG_RAM_RCMD 0x1D /* RAM read command */ + +/* Bits in PCF2127A_REG_CTL1 */ +#define PCF2127A_BIT_SI 0x01 /* second interrupt */ +#define PCF2127A_BIT_MI 0x02 /* minute interrupt */ +#define PCF2127A_BIT_H_24_12 0x04 /* 12/24 hour mode */ +#define PCF2127A_BIT_POR_OVRD 0x08 /* POR override */ +#define PCF2127A_BIT_TSF1 0x10 /* timestamp flag 1 */ +#define PCF2127A_BIT_STOP 0x20 /* stop bit */ +#define PCF2127A_BIT_EXTTEST 0x80 /* external clock test mode*/ + +/* Bits in PCF2127A_REG_CTL2 */ +#define PCF2127A_BIT_CDTIE 0x01 /* countdown timer flag */ +#define PCF2127A_BIT_AIE 0x02 /* alarm interrupt enable */ +#define PCF2127A_BIT_TSIE 0x04 /* timestamp int. enable */ +#define PCF2127A_BIT_CDTF 0x08 /* countdown timer flag */ +#define PCF2127A_BIT_AF 0x10 /* alarm flag */ +#define PCF2127A_BIT_TSF2 0x20 /* timestamp flag 2 */ +#define PCF2127A_BIT_WDTF 0x40 /* watchdog timer flag */ +#define PCF2127A_BIT_MSF 0x80 /* minute/second flag */ + +/* Bits in PCF2127A_REG_CTL3 */ +#define PCF2127A_BIT_BLIE 0x01 /* battery low Interrupt enable */ +#define PCF2127A_BIT_BIE 0x02 /* battery Switch int. enable */ +#define PCF2127A_BIT_BLF 0x04 /* battery low flag */ +#define PCF2127A_BIT_BF 0x08 /* battery switch flag */ +#define PCF2127A_BIT_BTSE 0x10 /* battery timestamp enable */ +#define PCF2127A_BIT_BLDOFF 0x20 /* battery low detection off */ +#define PCF2127A_BIT_BSM 0x40 /* battery switch mode */ +#define PCF2127A_BIT_BSOFF 0x80 /* battery switch off */ + +static struct i2c_driver pcf2127a_driver; + +struct pcf2127a { + struct rtc_device *rtc; +}; + +/* + * In the routines that deal directly with the pcf2127a hardware, we use + * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. + */ +static +int pcf2127a_get_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + unsigned char buf[10] = { PCF2127A_REG_CTL1 }; + + /* + * Note: We can't use i2c_transfer to send/recv multiple i2c_msg's + * to/from pcf2127a at once. The reason is that the pcf2127a doesn't + * handle (repeated START)-Conditions correctly. + * + * PCF2127A Manual, Section 9.2.2 START and STOP conditions: + * "Remark: For the PCF2127A a repeated START is not allowed. Therefore + * a STOP has to be released before the next START." + */ + /* setup read ptr */ + if (!i2c_master_send(client,buf,1)) { + dev_err(&client->dev, "%s: write error\n", __func__); + return -EIO; + } + + /* read status + date */ + if (!i2c_master_recv(client,buf,10)) { + dev_err(&client->dev, "%s: read error\n", __func__); + return -EIO; + } + + if (buf[PCF2127A_REG_CTL3] & PCF2127A_BIT_BLF) + dev_info(&client->dev, + "low battery detected, date/time is not reliable.\n"); + +#ifdef DEBUG + unsigned char bf_buf[2]; + if (buf[PCF2127A_REG_CTL3] & PCF2127A_BIT_BF){ + dev_info(&client->dev, + "battery switch-over detected - reset BF flag.\n"); + + bf_buf[0] = PCF2127A_REG_CTL3; + bf_buf[1] = buf[PCF2127A_REG_CTL3] & ~PCF2127A_BIT_BF; + if (!i2c_master_send(client, bf_buf, 2)) { + dev_err(&client->dev, "%s: write error\n", __func__); + return -EIO; + } + } +#endif + + dev_dbg(&client->dev, + "%s: raw data is ctl1=%02x, ctl2=%02x, ctl3=%02x, sec=%02x, " + "min=%02x, hour=%02x, day=%02x, wday=%02x, month=%02x, " + "year=%02x\n", + __func__, + buf[0], buf[1], buf[2], buf[3], + buf[4], buf[5], buf[6], buf[7], + buf[8], buf[9]); + + tm->tm_sec = bcd2bin(buf[PCF2127A_REG_SC] & 0x7F); + tm->tm_min = bcd2bin(buf[PCF2127A_REG_MN] & 0x7F); + tm->tm_hour = bcd2bin(buf[PCF2127A_REG_HR] & 0x3F); /* rtc hr 0-23 */ + tm->tm_mday = bcd2bin(buf[PCF2127A_REG_DM] & 0x3F); + tm->tm_wday = buf[PCF2127A_REG_DW] & 0x07; + tm->tm_mon = bcd2bin(buf[PCF2127A_REG_MO] & 0x1F) -1; /* rtc mn 1-12 */ + tm->tm_year = bcd2bin(buf[PCF2127A_REG_YR]); + + if (tm->tm_year < 70) + tm->tm_year += 100; /* assume we are in 1970...2069 */ + + 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 pcf2127a_set_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + int i, err; + unsigned char msgdata[2]; /* send data*/ + unsigned char buf[10]; /* Index 0 - 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[PCF2127A_REG_SC] = bin2bcd(tm->tm_sec); + buf[PCF2127A_REG_MN] = bin2bcd(tm->tm_min); + buf[PCF2127A_REG_HR] = bin2bcd(tm->tm_hour); + + /* day of month */ + buf[PCF2127A_REG_DM] = bin2bcd(tm->tm_mday); + + /* weekday */ + buf[PCF2127A_REG_DW] = tm->tm_wday & 0x07; + + /* month, 1 - 12 */ + buf[PCF2127A_REG_MO] = bin2bcd(tm->tm_mon + 1); + + /* year */ + buf[PCF2127A_REG_YR] = bin2bcd(tm->tm_year % 100); + + /* write register's data */ + for (i = 0; i < 7; i++) { + msgdata[0] = PCF2127A_REG_SC + i; + msgdata[1] = buf[PCF2127A_REG_SC + i]; + err = i2c_master_send(client, msgdata, sizeof(msgdata)); + if (err != sizeof(msgdata)) { + dev_err(&client->dev, + "%s: err=%d addr=%02x, data=%02x\n", + __func__, err, msgdata[0], msgdata[1]); + return -EIO; + } + } + + return 0; +} + +//***************************************************************************** + +static int pcf2127a_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + return pcf2127a_get_datetime(to_i2c_client(dev), tm); +} + +static int pcf2127a_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + return pcf2127a_set_datetime(to_i2c_client(dev), tm); +} + +static const struct rtc_class_ops pcf2127a_rtc_ops = { + .read_time = pcf2127a_rtc_read_time, + .set_time = pcf2127a_rtc_set_time, +}; + +//***************************************************************************** + +static int pcf2127a_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct pcf2127a *pcf2127a; + int err; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + pcf2127a = kzalloc(sizeof(struct pcf2127a), GFP_KERNEL); + if (!pcf2127a) + return -ENOMEM; + + dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); + + pcf2127a->rtc = rtc_device_register(pcf2127a_driver.driver.name, + &client->dev, &pcf2127a_rtc_ops, THIS_MODULE); + + if (IS_ERR(pcf2127a->rtc)) { + err = PTR_ERR(pcf2127a->rtc); + goto exit_kfree; + } + + i2c_set_clientdata(client, pcf2127a); + + return 0; + +exit_kfree: + kfree(pcf2127a); + + return err; +} + +//***************************************************************************** + +static +int pcf2127a_remove(struct i2c_client *client) +{ + struct pcf2127a *pcf2127a = i2c_get_clientdata(client); + + if (pcf2127a->rtc) + rtc_device_unregister(pcf2127a->rtc); + + kfree(pcf2127a); + + return 0; +} + +static const struct i2c_device_id pcf2127a_id[] = { + /* + * This driver should also work with the pcf2127, but + * I can't prove it. + */ + { "pcf2127a", 0 }, + { "rtc2127a", 0 }, +}; +MODULE_DEVICE_TABLE(i2c, pcf2127a_id); + +static struct i2c_driver pcf2127a_driver = { + .driver = { + .name = "rtc-pcf2127a", + }, + .probe = pcf2127a_probe, + .remove = pcf2127a_remove, + .id_table = pcf2127a_id, +}; + +static +int __init pcf2127a_init(void) +{ + return i2c_add_driver(&pcf2127a_driver); +} + +static +void __exit pcf2127a_exit(void) +{ + i2c_del_driver(&pcf2127a_driver); +} + +MODULE_AUTHOR("M. Wolf "); +MODULE_AUTHOR("T. Mehnert "); +MODULE_DESCRIPTION("NXP/Philips PCF2127A RTC (I2C) driver"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRV_VERSION); + +module_init(pcf2127a_init); +module_exit(pcf2127a_exit);