![Adrian Bunk](/assets/img/avatar_default.png)
Change drivers/rtc/ to use the new bcd2bin/bin2bcd functions instead of the obsolete BCD_TO_BIN/BIN_TO_BCD/BCD2BIN/BIN2BCD macros. Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
278 lines
6.5 KiB
C
278 lines
6.5 KiB
C
/* drivers/rtc/rtc-max6902.c
|
|
*
|
|
* Copyright (C) 2006 8D Technologies inc.
|
|
* Copyright (C) 2004 Compulab Ltd.
|
|
*
|
|
* 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.
|
|
*
|
|
* Driver for MAX6902 spi RTC
|
|
*
|
|
* Changelog:
|
|
*
|
|
* 24-May-2006: Raphael Assenat <raph@8d.com>
|
|
* - Major rework
|
|
* Converted to rtc_device and uses the SPI layer.
|
|
*
|
|
* ??-???-2005: Someone at Compulab
|
|
* - Initial driver creation.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/init.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/spi/spi.h>
|
|
#include <linux/bcd.h>
|
|
#include <linux/delay.h>
|
|
|
|
#define MAX6902_REG_SECONDS 0x01
|
|
#define MAX6902_REG_MINUTES 0x03
|
|
#define MAX6902_REG_HOURS 0x05
|
|
#define MAX6902_REG_DATE 0x07
|
|
#define MAX6902_REG_MONTH 0x09
|
|
#define MAX6902_REG_DAY 0x0B
|
|
#define MAX6902_REG_YEAR 0x0D
|
|
#define MAX6902_REG_CONTROL 0x0F
|
|
#define MAX6902_REG_CENTURY 0x13
|
|
|
|
#undef MAX6902_DEBUG
|
|
|
|
struct max6902 {
|
|
struct rtc_device *rtc;
|
|
u8 buf[9]; /* Burst read cmd + 8 registers */
|
|
u8 tx_buf[2];
|
|
u8 rx_buf[2];
|
|
};
|
|
|
|
static void max6902_set_reg(struct device *dev, unsigned char address,
|
|
unsigned char data)
|
|
{
|
|
struct spi_device *spi = to_spi_device(dev);
|
|
unsigned char buf[2];
|
|
|
|
/* MSB must be '0' to write */
|
|
buf[0] = address & 0x7f;
|
|
buf[1] = data;
|
|
|
|
spi_write(spi, buf, 2);
|
|
}
|
|
|
|
static int max6902_get_reg(struct device *dev, unsigned char address,
|
|
unsigned char *data)
|
|
{
|
|
struct spi_device *spi = to_spi_device(dev);
|
|
struct max6902 *chip = dev_get_drvdata(dev);
|
|
struct spi_message message;
|
|
struct spi_transfer xfer;
|
|
int status;
|
|
|
|
if (!data)
|
|
return -EINVAL;
|
|
|
|
/* Build our spi message */
|
|
spi_message_init(&message);
|
|
memset(&xfer, 0, sizeof(xfer));
|
|
xfer.len = 2;
|
|
/* Can tx_buf and rx_buf be equal? The doc in spi.h is not sure... */
|
|
xfer.tx_buf = chip->tx_buf;
|
|
xfer.rx_buf = chip->rx_buf;
|
|
|
|
/* Set MSB to indicate read */
|
|
chip->tx_buf[0] = address | 0x80;
|
|
|
|
spi_message_add_tail(&xfer, &message);
|
|
|
|
/* do the i/o */
|
|
status = spi_sync(spi, &message);
|
|
|
|
if (status == 0)
|
|
*data = chip->rx_buf[1];
|
|
return status;
|
|
}
|
|
|
|
static int max6902_get_datetime(struct device *dev, struct rtc_time *dt)
|
|
{
|
|
unsigned char tmp;
|
|
int century;
|
|
int err;
|
|
struct spi_device *spi = to_spi_device(dev);
|
|
struct max6902 *chip = dev_get_drvdata(dev);
|
|
struct spi_message message;
|
|
struct spi_transfer xfer;
|
|
int status;
|
|
|
|
err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &tmp);
|
|
if (err)
|
|
return err;
|
|
|
|
/* build the message */
|
|
spi_message_init(&message);
|
|
memset(&xfer, 0, sizeof(xfer));
|
|
xfer.len = 1 + 7; /* Burst read command + 7 registers */
|
|
xfer.tx_buf = chip->buf;
|
|
xfer.rx_buf = chip->buf;
|
|
chip->buf[0] = 0xbf; /* Burst read */
|
|
spi_message_add_tail(&xfer, &message);
|
|
|
|
/* do the i/o */
|
|
status = spi_sync(spi, &message);
|
|
if (status)
|
|
return status;
|
|
|
|
/* The chip sends data in this order:
|
|
* Seconds, Minutes, Hours, Date, Month, Day, Year */
|
|
dt->tm_sec = bcd2bin(chip->buf[1]);
|
|
dt->tm_min = bcd2bin(chip->buf[2]);
|
|
dt->tm_hour = bcd2bin(chip->buf[3]);
|
|
dt->tm_mday = bcd2bin(chip->buf[4]);
|
|
dt->tm_mon = bcd2bin(chip->buf[5]) - 1;
|
|
dt->tm_wday = bcd2bin(chip->buf[6]);
|
|
dt->tm_year = bcd2bin(chip->buf[7]);
|
|
|
|
century = bcd2bin(tmp) * 100;
|
|
|
|
dt->tm_year += century;
|
|
dt->tm_year -= 1900;
|
|
|
|
#ifdef MAX6902_DEBUG
|
|
printk("\n%s : Read RTC values\n",__func__);
|
|
printk("tm_hour: %i\n",dt->tm_hour);
|
|
printk("tm_min : %i\n",dt->tm_min);
|
|
printk("tm_sec : %i\n",dt->tm_sec);
|
|
printk("tm_year: %i\n",dt->tm_year);
|
|
printk("tm_mon : %i\n",dt->tm_mon);
|
|
printk("tm_mday: %i\n",dt->tm_mday);
|
|
printk("tm_wday: %i\n",dt->tm_wday);
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int max6902_set_datetime(struct device *dev, struct rtc_time *dt)
|
|
{
|
|
dt->tm_year = dt->tm_year+1900;
|
|
|
|
#ifdef MAX6902_DEBUG
|
|
printk("\n%s : Setting RTC values\n",__func__);
|
|
printk("tm_sec : %i\n",dt->tm_sec);
|
|
printk("tm_min : %i\n",dt->tm_min);
|
|
printk("tm_hour: %i\n",dt->tm_hour);
|
|
printk("tm_mday: %i\n",dt->tm_mday);
|
|
printk("tm_wday: %i\n",dt->tm_wday);
|
|
printk("tm_year: %i\n",dt->tm_year);
|
|
#endif
|
|
|
|
/* Remove write protection */
|
|
max6902_set_reg(dev, 0xF, 0);
|
|
|
|
max6902_set_reg(dev, 0x01, bin2bcd(dt->tm_sec));
|
|
max6902_set_reg(dev, 0x03, bin2bcd(dt->tm_min));
|
|
max6902_set_reg(dev, 0x05, bin2bcd(dt->tm_hour));
|
|
|
|
max6902_set_reg(dev, 0x07, bin2bcd(dt->tm_mday));
|
|
max6902_set_reg(dev, 0x09, bin2bcd(dt->tm_mon+1));
|
|
max6902_set_reg(dev, 0x0B, bin2bcd(dt->tm_wday));
|
|
max6902_set_reg(dev, 0x0D, bin2bcd(dt->tm_year%100));
|
|
max6902_set_reg(dev, 0x13, bin2bcd(dt->tm_year/100));
|
|
|
|
/* Compulab used a delay here. However, the datasheet
|
|
* does not mention a delay being required anywhere... */
|
|
/* delay(2000); */
|
|
|
|
/* Write protect */
|
|
max6902_set_reg(dev, 0xF, 0x80);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int max6902_read_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
return max6902_get_datetime(dev, tm);
|
|
}
|
|
|
|
static int max6902_set_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
return max6902_set_datetime(dev, tm);
|
|
}
|
|
|
|
static const struct rtc_class_ops max6902_rtc_ops = {
|
|
.read_time = max6902_read_time,
|
|
.set_time = max6902_set_time,
|
|
};
|
|
|
|
static int __devinit max6902_probe(struct spi_device *spi)
|
|
{
|
|
struct rtc_device *rtc;
|
|
unsigned char tmp;
|
|
struct max6902 *chip;
|
|
int res;
|
|
|
|
rtc = rtc_device_register("max6902",
|
|
&spi->dev, &max6902_rtc_ops, THIS_MODULE);
|
|
if (IS_ERR(rtc))
|
|
return PTR_ERR(rtc);
|
|
|
|
spi->mode = SPI_MODE_3;
|
|
spi->bits_per_word = 8;
|
|
spi_setup(spi);
|
|
|
|
chip = kzalloc(sizeof *chip, GFP_KERNEL);
|
|
if (!chip) {
|
|
rtc_device_unregister(rtc);
|
|
return -ENOMEM;
|
|
}
|
|
chip->rtc = rtc;
|
|
dev_set_drvdata(&spi->dev, chip);
|
|
|
|
res = max6902_get_reg(&spi->dev, MAX6902_REG_SECONDS, &tmp);
|
|
if (res) {
|
|
rtc_device_unregister(rtc);
|
|
return res;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __devexit max6902_remove(struct spi_device *spi)
|
|
{
|
|
struct max6902 *chip = platform_get_drvdata(spi);
|
|
struct rtc_device *rtc = chip->rtc;
|
|
|
|
if (rtc)
|
|
rtc_device_unregister(rtc);
|
|
|
|
kfree(chip);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct spi_driver max6902_driver = {
|
|
.driver = {
|
|
.name = "rtc-max6902",
|
|
.bus = &spi_bus_type,
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.probe = max6902_probe,
|
|
.remove = __devexit_p(max6902_remove),
|
|
};
|
|
|
|
static __init int max6902_init(void)
|
|
{
|
|
printk("max6902 spi driver\n");
|
|
return spi_register_driver(&max6902_driver);
|
|
}
|
|
module_init(max6902_init);
|
|
|
|
static __exit void max6902_exit(void)
|
|
{
|
|
spi_unregister_driver(&max6902_driver);
|
|
}
|
|
module_exit(max6902_exit);
|
|
|
|
MODULE_DESCRIPTION ("max6902 spi RTC driver");
|
|
MODULE_AUTHOR ("Raphael Assenat");
|
|
MODULE_LICENSE ("GPL");
|