rtc: rtc-max6902 fixes

- no changelogs in code
- no banners
- use local buffers
- fix probe sequence
- fixed style issues
- fix spi_write call
- removed old debug code

replaces http://patchwork.ozlabs.org/patch/9421/
and http://patchwork.ozlabs.org/patch/9455/

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: Raphael Assenat <raph@raphnet.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alessandro Zummo 2009-01-06 14:42:19 -08:00 committed by Linus Torvalds
parent 45fd8a0c14
commit a5771c6c42

View file

@ -9,14 +9,6 @@
*
* 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>
@ -26,7 +18,6 @@
#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
@ -38,16 +29,7 @@
#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,
static int max6902_set_reg(struct device *dev, unsigned char address,
unsigned char data)
{
struct spi_device *spi = to_spi_device(dev);
@ -57,113 +39,58 @@ static void max6902_set_reg(struct device *dev, unsigned char address,
buf[0] = address & 0x7f;
buf[1] = data;
spi_write(spi, buf, 2);
return spi_write_then_read(spi, buf, 2, NULL, 0);
}
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;
*data = 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;
return spi_write_then_read(spi, data, 1, data, 1);
}
static int max6902_get_datetime(struct device *dev, struct rtc_time *dt)
static int max6902_read_time(struct device *dev, struct rtc_time *dt)
{
unsigned char tmp;
int century;
int err;
int err, century;
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;
unsigned char buf[8];
err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &tmp);
if (err)
buf[0] = 0xbf; /* Burst read */
err = spi_write_then_read(spi, buf, 1, buf, 8);
if (err != 0)
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]);
dt->tm_sec = bcd2bin(buf[0]);
dt->tm_min = bcd2bin(buf[1]);
dt->tm_hour = bcd2bin(buf[2]);
dt->tm_mday = bcd2bin(buf[3]);
dt->tm_mon = bcd2bin(buf[4]) - 1;
dt->tm_wday = bcd2bin(buf[5]);
dt->tm_year = bcd2bin(buf[6]);
century = bcd2bin(tmp) * 100;
/* Read century */
err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &buf[0]);
if (err != 0)
return err;
century = bcd2bin(buf[0]) * 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;
return rtc_valid_tm(dt);
}
static int max6902_set_datetime(struct device *dev, struct rtc_time *dt)
static int max6902_set_time(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
dt->tm_year = dt->tm_year + 1900;
/* Remove write protection */
max6902_set_reg(dev, 0xF, 0);
@ -173,10 +100,10 @@ static int max6902_set_datetime(struct device *dev, struct rtc_time *dt)
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, 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));
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... */
@ -188,16 +115,6 @@ static int max6902_set_datetime(struct device *dev, struct rtc_time *dt)
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,
@ -207,45 +124,29 @@ static int __devinit max6902_probe(struct spi_device *spi)
{
struct rtc_device *rtc;
unsigned char tmp;
struct max6902 *chip;
int res;
spi->mode = SPI_MODE_3;
spi->bits_per_word = 8;
spi_setup(spi);
res = max6902_get_reg(&spi->dev, MAX6902_REG_SECONDS, &tmp);
if (res != 0)
return 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);
struct rtc_device *rtc = platform_get_drvdata(spi);
rtc_device_unregister(rtc);
return 0;
}
@ -261,7 +162,6 @@ static struct spi_driver max6902_driver = {
static __init int max6902_init(void)
{
printk("max6902 spi driver\n");
return spi_register_driver(&max6902_driver);
}
module_init(max6902_init);