From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934492Ab1JEL5g (ORCPT ); Wed, 5 Oct 2011 07:57:36 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:41979 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934221Ab1JEL5e (ORCPT ); Wed, 5 Oct 2011 07:57:34 -0400 From: Yauhen Kharuzhy To: Alessandro Zummo Cc: rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org, Ivan Kuten , Yauhen Kharuzhy Subject: [PATCH] RTC: Add driver for NXP PCF8523 RTC chip Date: Wed, 5 Oct 2011 14:57:03 +0300 Message-Id: <1317815823-27297-1-git-send-email-yauhen.kharuzhy@promwad.com> X-Mailer: git-send-email 1.7.6.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This driver is based on PCF8563 driver and supports only base functions now: read/write date & time. Signed-off-by: Yauhen Kharuzhy --- drivers/rtc/Kconfig | 9 ++ drivers/rtc/Makefile | 1 + drivers/rtc/rtc-pcf8523.c | 246 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 256 insertions(+), 0 deletions(-) create mode 100644 drivers/rtc/rtc-pcf8523.c diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 5a538fc..ace0259a 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -249,6 +249,15 @@ config RTC_DRV_X1205 This driver can also be built as a module. If so, the module will be called rtc-x1205. +config RTC_DRV_PCF8523 + tristate "NXP PCF8523" + help + If you say yes here you get support for the + NXP PCF8523 RTC chip. + + This driver can also be built as a module. If so, the module + will be called rtc-pcf8523. + config RTC_DRV_PCF8563 tristate "Philips PCF8563/Epson RTC8564" help diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 6e69823..7812730 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -71,6 +71,7 @@ obj-$(CONFIG_RTC_DRV_MV) += rtc-mv.o obj-$(CONFIG_RTC_DRV_NUC900) += rtc-nuc900.o obj-$(CONFIG_RTC_DRV_OMAP) += rtc-omap.o obj-$(CONFIG_RTC_DRV_PCAP) += rtc-pcap.o +obj-$(CONFIG_RTC_DRV_PCF8523) += rtc-pcf8523.o obj-$(CONFIG_RTC_DRV_PCF8563) += rtc-pcf8563.o obj-$(CONFIG_RTC_DRV_PCF8583) += rtc-pcf8583.o obj-$(CONFIG_RTC_DRV_PCF2123) += rtc-pcf2123.o diff --git a/drivers/rtc/rtc-pcf8523.c b/drivers/rtc/rtc-pcf8523.c new file mode 100644 index 0000000..06a6679 --- /dev/null +++ b/drivers/rtc/rtc-pcf8523.c @@ -0,0 +1,246 @@ +/* + * An I2C driver for the NXP PCF8523 RTC + * Copyright 2011 Promwad Innovation Company + * + * Author: Yauhen Kharuzhy + * Promwad Innovation Company, http://promwad.com/ + * + * based on the pcf8563 driver + * + * 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 +#include +#include +#include + +#define DRV_VERSION "1.0" + +#define PCF8523_REG_CTL1 0x00 /* control and status registers */ +#define PCF8523_REG_CTL2 0x01 +#define PCF8523_REG_CTL3 0x02 + +#define PCF8523_REG_SC 0x03 /* datetime */ +#define PCF8523_REG_MN 0x04 +#define PCF8523_REG_HR 0x05 +#define PCF8523_REG_DM 0x06 +#define PCF8523_REG_DW 0x07 +#define PCF8523_REG_MO 0x08 +#define PCF8523_REG_YR 0x09 + +#define PCF8523_REG_AMN 0x0A /* alarm */ +#define PCF8523_REG_AHR 0x0B +#define PCF8523_REG_ADM 0x0C +#define PCF8523_REG_ADW 0x0D + +#define PCF8523_REG_CLKO 0x0F /* clock out */ +#define PCF8523_REG_TMRAC 0x10 /* timer control */ +#define PCF8523_REG_TMRA 0x11 /* timer */ +#define PCF8523_REG_TMRBC 0x12 /* timer control */ +#define PCF8523_REG_TMRB 0x13 /* timer */ + +#define PCF8523_CTL3_BLF (1 << 2) + +static struct i2c_driver pcf8523_driver; + +/* + * In the routines that deal directly with the pcf8523 hardware, we use + * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. + */ +static int pcf8523_get_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + struct pcf8523 *pcf8523 = i2c_get_clientdata(client); + unsigned char buf[14] = { PCF8523_REG_CTL1 }; + + struct i2c_msg msgs[] = { + { client->addr, 0, 1, buf }, /* setup read ptr */ + { client->addr, I2C_M_RD, 14, 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[PCF8523_REG_CTL3] & PCF8523_CTL3_BLF) + dev_info(&client->dev, + "low voltage detected, date/time is not reliable.\n"); + + dev_dbg(&client->dev, + "%s: raw data is ctl1=%02x, ctl2=%02x, ctl3=%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], buf[9]); + + + tm->tm_sec = bcd2bin(buf[PCF8523_REG_SC] & 0x7F); + tm->tm_min = bcd2bin(buf[PCF8523_REG_MN] & 0x7F); + tm->tm_hour = bcd2bin(buf[PCF8523_REG_HR] & 0x3F); /* rtc hr 0-23 */ + tm->tm_mday = bcd2bin(buf[PCF8523_REG_DM] & 0x3F); + tm->tm_wday = buf[PCF8523_REG_DW] & 0x07; + tm->tm_mon = bcd2bin(buf[PCF8523_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */ + tm->tm_year = bcd2bin(buf[PCF8523_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 pcf8523_set_datetime(struct i2c_client *client, struct rtc_time *tm) +{ + struct pcf8523 *pcf8523 = i2c_get_clientdata(client); + int i, err; + unsigned char buf[10]; + + 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[PCF8523_REG_SC] = bin2bcd(tm->tm_sec); + buf[PCF8523_REG_MN] = bin2bcd(tm->tm_min); + buf[PCF8523_REG_HR] = bin2bcd(tm->tm_hour); + + buf[PCF8523_REG_DM] = bin2bcd(tm->tm_mday); + + /* month, 1 - 12 */ + buf[PCF8523_REG_MO] = bin2bcd(tm->tm_mon + 1); + + /* year and century */ + buf[PCF8523_REG_YR] = bin2bcd(tm->tm_year % 100); + + buf[PCF8523_REG_DW] = tm->tm_wday & 0x07; + + /* write register's data */ + for (i = 0; i < 7; i++) { + unsigned char data[2] = { PCF8523_REG_SC + i, + buf[PCF8523_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 pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + return pcf8523_get_datetime(to_i2c_client(dev), tm); +} + +static int pcf8523_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + return pcf8523_set_datetime(to_i2c_client(dev), tm); +} + +static const struct rtc_class_ops pcf8523_rtc_ops = { + .read_time = pcf8523_rtc_read_time, + .set_time = pcf8523_rtc_set_time, +}; + +static int pcf8523_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct pcf8523 *pcf8523; + + int err = 0; + + dev_dbg(&client->dev, "%s\n", __func__); + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) + return -ENODEV; + + pcf8523 = kzalloc(sizeof(struct pcf8523), GFP_KERNEL); + if (!pcf8523) + return -ENOMEM; + + dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n"); + + i2c_set_clientdata(client, pcf8523); + + pcf8523->rtc = rtc_device_register(pcf8523_driver.driver.name, + &client->dev, &pcf8523_rtc_ops, THIS_MODULE); + + if (IS_ERR(pcf8523->rtc)) { + err = PTR_ERR(pcf8523->rtc); + goto exit_kfree; + } + + return 0; + +exit_kfree: + kfree(pcf8523); + + return err; +} + +static int pcf8523_remove(struct i2c_client *client) +{ + struct pcf8523 *pcf8523 = i2c_get_clientdata(client); + + if (pcf8523->rtc) + rtc_device_unregister(pcf8523->rtc); + + kfree(pcf8523); + + return 0; +} + +static const struct i2c_device_id pcf8523_id[] = { + { "pcf8523", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pcf8523_id); + +static struct i2c_driver pcf8523_driver = { + .driver = { + .name = "rtc-pcf8523", + }, + .probe = pcf8523_probe, + .remove = pcf8523_remove, + .id_table = pcf8523_id, +}; + +static int __init pcf8523_init(void) +{ + return i2c_add_driver(&pcf8523_driver); +} + +static void __exit pcf8523_exit(void) +{ + i2c_del_driver(&pcf8523_driver); +} + +MODULE_AUTHOR("Yauhen Kharuzhy "); +MODULE_DESCRIPTION("NXP PCF8523"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(DRV_VERSION); + +module_init(pcf8523_init); +module_exit(pcf8523_exit); -- 1.7.6.3