From patchwork Fri Mar 21 14:35:40 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Raghavendra Ganiga X-Patchwork-Id: 332658 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from mail-yk0-x23b.google.com (mail-yk0-x23b.google.com [IPv6:2607:f8b0:4002:c07::23b]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 0EA782C007E for ; Sat, 22 Mar 2014 01:35:49 +1100 (EST) Received: by mail-yk0-f187.google.com with SMTP id 10sf1537724ykt.4 for ; Fri, 21 Mar 2014 07:35:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlegroups.com; s=20120806; h=message-id:date:from:user-agent:mime-version:to:subject :x-original-sender:x-original-authentication-results:reply-to :precedence:mailing-list:list-id:list-post:list-help:list-archive :sender:list-subscribe:list-unsubscribe:content-type; bh=FACla/kMXrGEN+wCBvPVq20plJa5EaDo7W4UtlKAhxQ=; b=nxngHIkB5fGSTbC26RTI0/4Gmj0aAo14rJTE1w4YaGr/sPTZiLhxpVvYGTOJLC1d2u Oe8lGyxKaNKqw0flkn/GjoVP+vxQ+K3dU/zV8epXE0LYY+s93VSM7EyQ/z1YUTbZlZlM MICIcYTQsX0hRiSQMPOJc6tKsCyjQqlc9UxnsaK7g4TDLD8ldL9jPiMCxVa3Vrt+wyNQ 7HzoANNJtOtF2XKJL9HwhqCnX6/2gAx3dqhFF0+Cjl0LIsptOTtDT/sFxvpHs36AuFd1 k5p6Ad4kxdxYpVfIYvtOvPDsn53sa411+yI/6j7B9B3wS0zqMPqUhlyLhqDGJajtTN+f T/YA== X-Received: by 10.140.93.109 with SMTP id c100mr23512qge.21.1395412547164; Fri, 21 Mar 2014 07:35:47 -0700 (PDT) X-BeenThere: rtc-linux@googlegroups.com Received: by 10.140.91.131 with SMTP id z3ls694959qgd.59.gmail; Fri, 21 Mar 2014 07:35:46 -0700 (PDT) X-Received: by 10.52.61.197 with SMTP id s5mr4562380vdr.8.1395412546718; Fri, 21 Mar 2014 07:35:46 -0700 (PDT) Received: from mail-pa0-x234.google.com (mail-pa0-x234.google.com [2607:f8b0:400e:c03::234]) by gmr-mx.google.com with ESMTPS id pt3si2059572pac.0.2014.03.21.07.35.45 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 21 Mar 2014 07:35:45 -0700 (PDT) Received-SPF: pass (google.com: domain of ravi23ganiga@gmail.com designates 2607:f8b0:400e:c03::234 as permitted sender) client-ip=2607:f8b0:400e:c03::234; Received: by mail-pa0-x234.google.com with SMTP id rd3so2487678pab.39 for ; Fri, 21 Mar 2014 07:35:45 -0700 (PDT) X-Received: by 10.67.2.106 with SMTP id bn10mr54137836pad.38.1395412545483; Fri, 21 Mar 2014 07:35:45 -0700 (PDT) Received: from [192.168.42.153] ([219.91.250.213]) by mx.google.com with ESMTPSA id qx11sm27171197pab.35.2014.03.21.07.35.42 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 21 Mar 2014 07:35:44 -0700 (PDT) Message-ID: <532C4E3C.8030404@gmail.com> Date: Fri, 21 Mar 2014 20:05:40 +0530 From: RAGHAVENDRA GANIGA User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121010 Thunderbird/16.0.1 MIME-Version: 1.0 To: a.zummo@towertech.it, linux-kernel@vger.kernel.org, rtc-linux@googlegroups.com Subject: [rtc-linux] [PATCH] rtc: add support for maxim dallas rtc ds1347 X-Original-Sender: ravi23ganiga@gmail.com X-Original-Authentication-Results: gmr-mx.google.com; spf=pass (google.com: domain of ravi23ganiga@gmail.com designates 2607:f8b0:400e:c03::234 as permitted sender) smtp.mail=ravi23ganiga@gmail.com; dkim=pass header.i=@gmail.com; dmarc=pass (p=NONE dis=NONE) header.from=gmail.com Reply-To: rtc-linux@googlegroups.com Precedence: list Mailing-list: list rtc-linux@googlegroups.com; contact rtc-linux+owners@googlegroups.com List-ID: X-Google-Group-Id: 712029733259 List-Post: , List-Help: , List-Archive: Sender: rtc-linux@googlegroups.com List-Subscribe: , List-Unsubscribe: , From 0fd7f9ab5c0cb5e857b7b4d6893a8e68ac7763fd Mon Sep 17 00:00:00 2001 From: Raghavendra Ganiga Date: Fri, 21 Mar 2014 19:53:36 +0530 Subject: [PATCH] rtc: add support for maxim dallas rtc ds1347 This is a patch to add support for maxim dallas rtc ds1347 Signed-off-by: Raghavendra Chandra Ganiga --- drivers/rtc/Kconfig | 12 ++++ drivers/rtc/Makefile | 1 + drivers/rtc/rtc-ds1347.c | 167 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 180 insertions(+) create mode 100644 drivers/rtc/rtc-ds1347.c diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index db933de..2e565f8 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -573,6 +573,18 @@ config RTC_DRV_DS1305 This driver can also be built as a module. If so, the module will be called rtc-ds1305. +config RTC_DRV_DS1347 + tristate "Dallas/Maxim DS1347" + help + If you say yes here you get support for the + Dallas/Maxim DS1347 chips. + + This driver only supports the RTC feature, and not other chip + features such as alarms. + + This driver can also be built as a module. If so, the module + will be called rtc-ds1347. + config RTC_DRV_DS1390 tristate "Dallas/Maxim DS1390/93/94" help diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index b427bf7..40a0991 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_RTC_DRV_DS1286) += rtc-ds1286.o obj-$(CONFIG_RTC_DRV_DS1302) += rtc-ds1302.o obj-$(CONFIG_RTC_DRV_DS1305) += rtc-ds1305.o obj-$(CONFIG_RTC_DRV_DS1307) += rtc-ds1307.o +obj-$(CONFIG_RTC_DRV_DS1347) += rtc-ds1347.o obj-$(CONFIG_RTC_DRV_DS1374) += rtc-ds1374.o obj-$(CONFIG_RTC_DRV_DS1390) += rtc-ds1390.o obj-$(CONFIG_RTC_DRV_DS1511) += rtc-ds1511.o diff --git a/drivers/rtc/rtc-ds1347.c b/drivers/rtc/rtc-ds1347.c new file mode 100644 index 0000000..fffa51f --- /dev/null +++ b/drivers/rtc/rtc-ds1347.c @@ -0,0 +1,167 @@ +/* rtc-ds1347.c + * + * Driver for Dallas Semiconductor DS1347 Low Current, SPI Compatible + * Real Time Clock + * + * Author : Raghavendra Chandra Ganiga + * + * 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 +#include +#include +#include + +/* Registers in ds1347 rtc */ + +#define DS1347_SECONDS_REG 0x01 +#define DS1347_MINUTES_REG 0x03 +#define DS1347_HOURS_REG 0x05 +#define DS1347_DATE_REG 0x07 +#define DS1347_MONTH_REG 0x09 +#define DS1347_DAY_REG 0x0B +#define DS1347_YEAR_REG 0x0D +#define DS1347_CONTROL_REG 0x0F +#define DS1347_STATUS_REG 0x17 +#define DS1347_CLOCK_BURST 0x3F + +static int ds1347_read_reg(struct device *dev, unsigned char address, + unsigned char *data) +{ + struct spi_device *spi = to_spi_device(dev); + + *data = address | 0x80; + + return spi_write_then_read(spi, data, 1, data, 1); +} + +static int ds1347_write_reg(struct device *dev, unsigned char address, + unsigned char data) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned char buf[2]; + + buf[0] = address & 0x7F; + buf[1] = data; + + return spi_write_then_read(spi, buf, 2, NULL, 0); +} + +static int ds1347_read_time(struct device *dev, struct rtc_time *dt) +{ + struct spi_device *spi = to_spi_device(dev); + int err; + unsigned char buf[8]; + + buf[0] = DS1347_CLOCK_BURST | 0x80; + + err = spi_write_then_read(spi, buf, 1, buf, 8); + if (err) + return err; + + dt->tm_sec = bcd2bin(buf[0]); + dt->tm_min = bcd2bin(buf[1]); + dt->tm_hour = bcd2bin(buf[2] & 0x3F); + dt->tm_mday = bcd2bin(buf[3]); + dt->tm_mon = bcd2bin(buf[4]) - 1; + dt->tm_wday = bcd2bin(buf[5]) - 1; + dt->tm_year = bcd2bin(buf[6]) + 100; + + return rtc_valid_tm(dt); +} + +static int ds1347_set_time(struct device *dev, struct rtc_time *dt) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned char buf[9]; + + buf[0] = DS1347_CLOCK_BURST & 0x7F; + buf[1] = bin2bcd(dt->tm_sec); + buf[2] = bin2bcd(dt->tm_min); + buf[3] = (bin2bcd(dt->tm_hour) & 0x3F); + buf[4] = bin2bcd(dt->tm_mday); + buf[5] = bin2bcd(dt->tm_mon + 1); + buf[6] = bin2bcd(dt->tm_wday + 1); + + /* year in linux is from 1900 i.e in range of 100 + in rtc it is from 00 to 99 */ + dt->tm_year = dt->tm_year % 100; + + buf[7] = bin2bcd(dt->tm_year); + buf[8] = bin2bcd(0x00); + + /* write the rtc settings */ + return spi_write_then_read(spi, buf, 9, NULL, 0); +} + +static const struct rtc_class_ops ds1347_rtc_ops = { + .read_time = ds1347_read_time, + .set_time = ds1347_set_time, +}; + +static int ds1347_probe(struct spi_device *spi) +{ + struct rtc_device *rtc; + unsigned char data; + int res; + + /* spi setup with ds1347 in mode 3 and bits per word as 8 */ + spi->mode = SPI_MODE_3; + spi->bits_per_word = 8; + spi_setup(spi); + + /* RTC Settings */ + res = ds1347_read_reg(&spi->dev, DS1347_SECONDS_REG, &data); + if (res) + return res; + + /* Disable the write protect of rtc */ + ds1347_read_reg(&spi->dev, DS1347_CONTROL_REG, &data); + data = data & ~(1<<7); + ds1347_write_reg(&spi->dev, DS1347_CONTROL_REG, data); + + /* Enable the oscillator , disable the oscillator stop flag, + and glitch filter to reduce current consumption */ + ds1347_read_reg(&spi->dev, DS1347_STATUS_REG, &data); + data = data & 0x1B; + ds1347_write_reg(&spi->dev, DS1347_STATUS_REG, data); + + /* display the settings */ + ds1347_read_reg(&spi->dev, DS1347_CONTROL_REG, &data); + dev_info(&spi->dev, "DS1347 RTC CTRL Reg = 0x%02x\n", data); + + ds1347_read_reg(&spi->dev, DS1347_STATUS_REG, &data); + dev_info(&spi->dev, "DS1347 RTC Status Reg = 0x%02x\n", data); + + rtc = devm_rtc_device_register(&spi->dev, "ds1347", + &ds1347_rtc_ops, THIS_MODULE); + + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + spi_set_drvdata(spi, rtc); + + return 0; +} + +static struct spi_driver ds1347_driver = { + .driver = { + .name = "ds1347", + .owner = THIS_MODULE, + }, + .probe = ds1347_probe, +}; + +module_spi_driver(ds1347_driver); + +MODULE_DESCRIPTION("DS1347 SPI RTC DRIVER"); +MODULE_AUTHOR("Raghavendra C Ganiga "); +MODULE_LICENSE("GPL v2"); +