From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Sender: rtc-linux@googlegroups.com Received: from mail.free-electrons.com (down.free-electrons.com. [37.187.137.238]) by gmr-mx.google.com with ESMTP id u18si725972wmd.1.2016.05.10.06.20.56 for ; Tue, 10 May 2016 06:20:56 -0700 (PDT) Date: Tue, 10 May 2016 15:20:55 +0200 From: Alexandre Belloni To: venkat.prashanth2498@gmail.com Cc: a.zummo@towertech.it, rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org, marcus.folkesson@gmail.com Subject: [rtc-linux] Re: [PATCH] rtc: add support to maxim rtc max6916 v2.0 Message-ID: <20160510132055.GU2890@piout.net> References: <1462526164-6086-1-git-send-email-venkat.prashanth2498@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 In-Reply-To: <1462526164-6086-1-git-send-email-venkat.prashanth2498@gmail.com> Reply-To: rtc-linux@googlegroups.com List-ID: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , Hi, Again, please use checkpatch.pl --strict before sending a patch. On 06/05/2016 at 02:16:04 -0700, venkat.prashanth2498@gmail.com wrote : > From: venkat-prashanth >=20 > This is a patch to add=20 > support for maxim rtc MAX6916 >=20 > Signed-off-by : Venkat Prashanth B U > --- The changelog should appear here, not in a separate file. > Kconfig | 10 ++++ > changeLOG | 36 ++++++++++++ > rtc-max6916.c | 172 ++++++++++++++++++++++++++++++++++++++++++++++++++++= ++++++ You are missing modifications in the Makefile. > 3 files changed, 218 insertions(+) >=20 > diff --git a/drivers/rtcKconfig b/drivers/rtc/Kconfig > index e69de29..81aaa1e 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -0,0 +1,10 @@ > +config RTC_DRV_MAX6916 > +tristate "Maxim MAX6916" > + > +help > +If you say yes here you get support for the > +Maxim MAX6916 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=E2=80=90max6916. This is badly indented. > diff --git a/changeLOG b/changeLOG > index e69de29..6aa0a76 100644 > --- a/drivers/rtc/changeLOG > +++ b/drivers/rtc/changeLOG > @@ -0,0 +1,36 @@ > +Changes incorporated after pre-commit review > + > +1./*created folders=20 > +drivers/rtc/rtc-max6916.c > +drivers/rtc/Kconfig/ > + > +2./*deleted the port i/o's since it does not add=20 > +any significance in overall system design aspect*/ > +/*=20 > +#define ADDRESS_REG 0x70 > +#define DATA_REG 0x71 > +#define ADDRESS_REG_MASK 0xe0 > + > +static unsigned char get_rtc(unsigned char addr) > +{ > +outb(addr, ADDRESS_REG); > +return inb(DATA_REG); > +}*/ > + > +3./* Clock burst value is modified from 0X00 to 0X3F and=20 > +further get_rtc() function is replaced with bcd2bin()=20 > +since the time in Linux is in binary format so the conversion is done*/ > + > + > +4./*enforced the year range instead of accepting any value > +which is as follows: > +/* starting from year 2000,limit to 100 years from now > +that is subtract the year by 100 */ > +dt->tm_year =3D dt->tm_year % 100; > +if(dt->tm_year >=3D 100) > +dt->tm_year -=3D 100; > + > +if (dt->tm_year < 100 || dt->tm_year > 199) { > + dev_err(&spi->dev, "Year must be between 2000 and 2099. It's %d.\n",dt= ->tm_year + 1900); > + return -EINVAL; > +}*/ > diff --git a/drivers/rtc/rtc-max6916.c b/drivers/rtc/rtc-max6916.c > index e69de29..f5e396f 100644 > --- a/drivers/rtc/rtc-max6916.c > +++ b/drivers/rtc/rtc-max6916.c > @@ -0,0 +1,172 @@ > +/* rtc-max6916.c > + * > + * Driver for MAXIM max6916 Low Current, SPI Compatible > + * Real Time Clock > + * > + * Author : Venkat Prashanth B U > + * > + * 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. > + * > + */ > +=20 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Registers in max6916 rtc */ > + > +#define MAX6916_SECONDS_REG 0x01 > +#define MAX6916_MINUTES_REG 0x02 > +#define MAX6916_HOURS_REG 0x03 > +#define MAX6916_DATE_REG 0x04 > +#define MAX6916_MONTH_REG 0x05 > +#define MAX6916_DAY_REG 0x06 > +#define MAX6916_YEAR_REG 0x07 > +#define MAX6916_CONTROL_REG 0x08 > +#define MAX6916_STATUS_REG 0x0C > +#define MAX6916_CLOCK_BURST 0x3F > + > +static int max6916_read_reg(struct device *dev, unsigned char address,= =20 > + unsigned char *data) > +{ > + struct spi_device *spi =3D to_spi_device(dev); > + > + *data =3D address | 0x80; > + > + return spi_write_then_read(spi, data, 1, data, 1); > +} > + > +static int max6916_write_reg(struct device *dev, unsigned char address,= =20 > + unsigned char data) > +{ > + struct spi_device *spi =3D to_spi_device(dev); > + unsigned char buf[2]; > + > + buf[0] =3D address&0x7F; > + buf[1] =3D data; > + > + return spi_write_then_read(spi, buf, 2, NULL, 0); > +} > + > +static int max6916_read_time(struct device *dev, struct rtc_time *dt) > +{ > + struct spi_device *spi =3D to_spi_device(dev); > + int err; > + unsigned char buf[8]; > + > + buf[0] =3D MAX6916_CLOCK_BURST | 0x80; > +=09 > + err =3D spi_write_then_read(spi, buf, 1, buf, 8); > + if (err) > + return err; > + =09 > + dt->tm_sec =3D bcd2bin(buf[0]); > + dt->tm_min =3D bcd2bin(buf[1]); > + dt->tm_hour =3D bcd2bin(buf[2] & 0x3F); > + dt->tm_mday =3D bcd2bin(buf[3]); > + dt->tm_mon =3D bcd2bin(buf[4]) - 1; > + dt->tm_wday =3D bcd2bin(buf[5]) - 1; > + dt->tm_year =3D bcd2bin(buf[6]) + 100; > + > + return rtc_valid_tm(dt); > +} > + > +static int max6916_set_time(struct device *dev, struct rtc_time *dt) > +{ > + struct spi_device *spi =3D to_spi_device(dev); > + unsigned char buf[9]; > + > + buf[0] =3D MAX6916_CLOCK_BURST & 0x7F; > + buf[1] =3D bin2bcd(dt->tm_sec); > + buf[2] =3D bin2bcd(dt->tm_min); > + buf[3] =3D (bin2bcd(dt->tm_hour)& 0X3F); > + buf[4] =3D bin2bcd(dt->tm_mday); > + buf[5] =3D bin2bcd(dt->tm_mon + 1); > + buf[6] =3D bin2bcd(dt->tm_wday + 1); > + > + /* starting from year 2000,limit to 100 years=20 > + from now that is subtract the year by 100 */ > + dt->tm_year =3D dt->tm_year % 100; This is unnecessary > + if(dt->tm_year >=3D 100) You don't need that test if the range is properly enforced. > + dt->tm_year -=3D 100; > + =09 > + if (dt->tm_year < 100 || dt->tm_year > 199) { > + dev_err(&spi->dev,"Year must be between 2000 and 2099. It's %d.\n", dt= ->tm_year + 1900); > + return -EINVAL; > + } This test should go at the beginning of the function. > + =09 > + buf[7] =3D bin2bcd(dt->tm_year); > + buf[8] =3D bin2bcd(0x00); > +=09 > + /* write the rtc settings */ > + return spi_write_then_read(spi, buf, 9, NULL, 0); > +} > + > +static const struct rtc_class_ops max6916_rtc_ops =3D { > + .read_time =3D max6916_read_time, > + .set_time =3D max6916_set_time, > +}; > + > +static int max6916_probe(struct spi_device *spi) > +{ > + struct rtc_device *rtc; > + unsigned char data; > + int res; > + > + /* spi setup with max6916 in mode 3 and bits per word as 8 */ > + spi->mode =3D SPI_MODE_3; > + spi->bits_per_word =3D 8; > + spi_setup(spi); > + > + /* RTC Settings */ > + res =3D max6916_read_reg(&spi->dev, MAX6916_SECONDS_REG , &data); > +=09 > + if (res) > + return res; > + > + /* Disable the write protect of rtc */ > + max6916_read_reg(&spi->dev, MAX6916_CONTROL_REG, &data); > + data =3D data & ~(1<<7); Please use defines instead of magic values > + max6916_write_reg(&spi->dev, MAX6916_CONTROL_REG, data); > + > + /*Enable the oscillator,disable the oscillator stop flag, and glitch fi= lter to reduce current consumption*/ > + max6916_read_reg(&spi->dev, MAX6916_STATUS_REG, &data); > + data =3D data & 0x1B; Also use a define instead of 0x1B. --=20 Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --=20 --=20 You received this message because you are subscribed to "rtc-linux". Membership options at http://groups.google.com/group/rtc-linux . Please read http://groups.google.com/group/rtc-linux/web/checklist before submitting a driver. ---=20 You received this message because you are subscribed to the Google Groups "= rtc-linux" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to rtc-linux+unsubscribe@googlegroups.com. For more options, visit https://groups.google.com/d/optout.