[PATCH][v1] RTC driver(Linux) for PT7C4338 chip.
Jain Priyanka-B32167
B32167 at freescale.com
Tue Feb 8 15:31:16 EST 2011
Hi,
Please review and acknowledge this patch.
Regards
Priyanka
> -----Original Message-----
> From: Jain Priyanka-B32167
> Sent: Monday, November 22, 2010 9:24 AM
> To: 'Alessandro Zummo'
> Cc: 'rtc-linux at googlegroups.com'
> Subject: FW: [PATCH][v1] RTC driver(Linux) for PT7C4338 chip.
>
> Hi,
>
> Please review and acknowledge this patch.
>
> Thanks and Regards
> Priyanka
>
>
>
> -----Original Message-----
> From: Jain Priyanka-B32167
> Sent: Thursday, November 11, 2010 9:36 AM
> To: Jain Priyanka-B32167; rtc-linux at googlegroups.com; linuxppc-
> dev at lists.ozlabs.org
> Subject: RE: [PATCH][v1] RTC driver(Linux) for PT7C4338 chip.
>
> Hi,
>
> I am waiting for review comments and acknowledgement that this patch will
> be pick up for open source.
> Please acknowledge.
>
> Regards
> Priyanka Jain
>
> -----Original Message-----
> From: Jain Priyanka-B32167
> Sent: Tuesday, October 26, 2010 3:12 PM
> To: rtc-linux at googlegroups.com; linuxppc-dev at lists.ozlabs.org
> Cc: Jain Priyanka-B32167
> Subject: [PATCH][v1] RTC driver(Linux) for PT7C4338 chip.
>
> PT7C4338 chip is being manufactured by Pericom Technology Inc.
> It is a serial real-time clock which provides:
> 1)Low-power clock/calendar.
> 2)Programmable square-wave output.
> It has 56 bytes of nonvolatile RAM.
>
> Signed-off-by: Priyanka Jain <Priyanka.Jain at freescale.com>
> ---
> PT7C4338 RTC driver is verified on Freescale P1010RDB.
> Changes for v1:
> Incoperated Kumar Gala's review comments
> -Removing board name from commit messages.
>
> drivers/rtc/Kconfig | 9 ++
> drivers/rtc/Makefile | 1 +
> drivers/rtc/rtc-pt7c4338.c | 215
> ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 225 insertions(+), 0 deletions(-) create mode 100644
> drivers/rtc/rtc-pt7c4338.c
>
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index
> 10ba12c..6ff0901 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -324,6 +324,15 @@ config RTC_DRV_RX8025
> This driver can also be built as a module. If so, the module
> will be called rtc-rx8025.
>
> +config RTC_DRV_PT7C4338
> + tristate "Pericom Technology Inc. PT7C4338 RTC"
> + help
> + If you say yes here you get support for the Pericom Technology
> + Inc. PT7C4338 RTC chip.
> +
> + This driver can also be built as a module. If so, the module
> + will be called rtc-pt7c4338.
> +
> endif # I2C
>
> comment "SPI RTC drivers"
> diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index
> 5adbba7..4014607 100644
> --- a/drivers/rtc/Makefile
> +++ b/drivers/rtc/Makefile
> @@ -70,6 +70,7 @@ obj-$(CONFIG_RTC_DRV_PCF50633) += rtc-pcf50633.o
> obj-$(CONFIG_RTC_DRV_PL030) += rtc-pl030.o
> obj-$(CONFIG_RTC_DRV_PL031) += rtc-pl031.o
> obj-$(CONFIG_RTC_DRV_PS3) += rtc-ps3.o
> +obj-$(CONFIG_RTC_DRV_PT7C4338) += rtc-pt7c4338.o
> obj-$(CONFIG_RTC_DRV_PXA) += rtc-pxa.o
> obj-$(CONFIG_RTC_DRV_R9701) += rtc-r9701.o
> obj-$(CONFIG_RTC_DRV_RP5C01) += rtc-rp5c01.o
> diff --git a/drivers/rtc/rtc-pt7c4338.c b/drivers/rtc/rtc-pt7c4338.c new
> file mode 100644 index 0000000..fca52cd
> --- /dev/null
> +++ b/drivers/rtc/rtc-pt7c4338.c
> @@ -0,0 +1,215 @@
> +/*
> + * Copyright 2010 Freescale Semiconductor, Inc.
> + *
> + * Author: Priyanka Jain <Priyanka.Jain at freescale.com>
> + *
> + * See file CREDITS for list of people who contributed to this
> + * project.
> + *
> + * 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., 59 Temple Place, Suite 330, Boston,
> + * MA 02111-1307 USA
> + */
> +
> +/*
> + * This file provides Date & Time support (no alarms) for PT7C4338 chip.
> + *
> + * This file is based on drivers/rtc/rtc-ds1307.c
> + *
> + * PT7C4338 chip is manufactured by Pericom Technology Inc.
> + * It is a serial real-time clock which provides
> + * 1)Low-power clock/calendar.
> + * 2)Programmable square-wave output.
> + * It has 56 bytes of nonvolatile RAM.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/rtc.h>
> +#include <linux/bcd.h>
> +
> +/* RTC register addresses */
> +#define PT7C4338_REG_SECONDS 0x00
> +#define PT7C4338_REG_MINUTES 0x01
> +#define PT7C4338_REG_HOURS 0x02
> +#define PT7C4338_REG_AMPM 0x02
> +#define PT7C4338_REG_DAY 0x03
> +#define PT7C4338_REG_DATE 0x04
> +#define PT7C4338_REG_MONTH 0x05
> +#define PT7C4338_REG_YEAR 0x06
> +#define PT7C4338_REG_CTRL_STAT 0x07
> +
> +/* RTC second register address bit */
> +#define PT7C4338_SEC_BIT_CH 0x80 /*Clock Halt (in Register
> 0)*/
> +
> +/* RTC control and status register bits */
> +#define PT7C4338_CTRL_STAT_BIT_RS0 0x1 /*Rate select 0*/
> +#define PT7C4338_CTRL_STAT_BIT_RS1 0x2 /*Rate select 1*/
> +#define PT7C4338_CTRL_STAT_BIT_SQWE 0x10 /*Square Wave Enable*/
> +#define PT7C4338_CTRL_STAT_BIT_OSF 0x20 /*Oscillator Stop Flag*/
> +#define PT7C4338_CTRL_STAT_BIT_OUT 0x80 /*Output Level Control*/
> +
> +static const struct i2c_device_id pt7c4338_id[] = {
> + { "pt7c4338", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, pt7c4338_id);
> +
> +struct pt7c4338{
> + struct i2c_client *client;
> + struct rtc_device *rtc;
> +};
> +
> +static int pt7c4338_read_time(struct device *dev, struct rtc_time
> +*time) {
> + struct i2c_client *client = to_i2c_client(dev);
> + int ret;
> + u8 buf[7];
> + u8 year, month, day, hour, minute, second;
> + u8 week, twelve_hr, am_pm;
> +
> + ret = i2c_smbus_read_i2c_block_data(client,
> + PT7C4338_REG_SECONDS, 7, buf);
> + if (ret < 0)
> + return ret;
> + if (ret < 7)
> + return -EIO;
> +
> + second = buf[0];
> + minute = buf[1];
> + hour = buf[2];
> + week = buf[3];
> + day = buf[4];
> + month = buf[5];
> + year = buf[6];
> +
> + /* Extract additional information for AM/PM */
> + twelve_hr = hour & 0x40;
> + am_pm = hour & 0x20;
> +
> + /* Write to rtc_time structure */
> + time->tm_sec = bcd2bin(second & 0x7f);
> + time->tm_min = bcd2bin(minute & 0x7f);
> + if (twelve_hr) {
> + /* Convert to 24 hr */
> + if (am_pm)
> + time->tm_hour = bcd2bin(hour & 0x10) + 12;
> + else
> + time->tm_hour = bcd2bin(hour & 0xBF);
> + } else {
> + time->tm_hour = bcd2bin(hour);
> + }
> +
> + time->tm_wday = bcd2bin(week & 0x07) - 1;
> + time->tm_mday = bcd2bin(day & 0x3f);
> + time->tm_mon = bcd2bin(month & 0x1F) - 1;
> + /* assume 20YY not 19YY */
> + time->tm_year = bcd2bin(year) + 100;
> +
> + return 0;
> +}
> +
> +static int pt7c4338_set_time(struct device *dev, struct rtc_time *time)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + u8 buf[7];
> +
> + /* Extract time from rtc_time and load into pt7c4338*/
> + buf[0] = bin2bcd(time->tm_sec);
> + buf[1] = bin2bcd(time->tm_min);
> + buf[2] = bin2bcd(time->tm_hour);
> + buf[3] = bin2bcd(time->tm_wday + 1); /* Day of the week */
> + buf[4] = bin2bcd(time->tm_mday); /* Date */
> + buf[5] = bin2bcd(time->tm_mon + 1);
> +
> + /* assume 20YY not 19YY */
> + if (time->tm_year >= 100)
> + buf[6] = bin2bcd(time->tm_year - 100);
> + else
> + buf[6] = bin2bcd(time->tm_year);
> +
> + return i2c_smbus_write_i2c_block_data(client,
> + PT7C4338_REG_SECONDS, 7, buf);
> +}
> +
> +static const struct rtc_class_ops pt7c4338_rtc_ops = {
> + .read_time = pt7c4338_read_time,
> + .set_time = pt7c4338_set_time,
> +};
> +
> +static int pt7c4338_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct pt7c4338 *pt7c4338;
> + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
> + int ret;
> +
> + pt7c4338 = kzalloc(sizeof(struct pt7c4338), GFP_KERNEL);
> + if (!pt7c4338)
> + return -ENOMEM;
> +
> + pt7c4338->client = client;
> + i2c_set_clientdata(client, pt7c4338);
> + pt7c4338->rtc = rtc_device_register(client->name, &client->dev,
> + &pt7c4338_rtc_ops, THIS_MODULE);
> + if (IS_ERR(pt7c4338->rtc)) {
> + ret = PTR_ERR(pt7c4338->rtc);
> + dev_err(&client->dev, "unable to register the class
> device\n");
> + goto out_free;
> + }
> +
> + return 0;
> +out_free:
> + i2c_set_clientdata(client, NULL);
> + kfree(pt7c4338);
> + return ret;
> +}
> +
> +static int __devexit pt7c4338_remove(struct i2c_client *client) {
> + struct pt7c4338 *pt7c4338 = i2c_get_clientdata(client);
> +
> + rtc_device_unregister(pt7c4338->rtc);
> + i2c_set_clientdata(client, NULL);
> + kfree(pt7c4338);
> + return 0;
> +}
> +
> +static struct i2c_driver pt7c4338_driver = {
> + .driver = {
> + .name = "rtc-pt7c4338",
> + .owner = THIS_MODULE,
> + },
> + .probe = pt7c4338_probe,
> + .remove = __devexit_p(pt7c4338_remove),
> + .id_table = pt7c4338_id,
> +};
> +
> +static int __init pt7c4338_init(void)
> +{
> + return i2c_add_driver(&pt7c4338_driver); }
> +
> +static void __exit pt7c4338_exit(void)
> +{
> + i2c_del_driver(&pt7c4338_driver);
> +}
> +
> +module_init(pt7c4338_init);
> +module_exit(pt7c4338_exit);
> +
> +MODULE_AUTHOR("Priyanka Jain <Priyanka.Jain at freescale.com>");
> +MODULE_DESCRIPTION("pericom Technology Inc. PT7C4338 RTC Driver");
> +MODULE_LICENSE("GPL");
> --
> 1.6.5.6
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