linux/drivers/rtc/rtc-rx8025.c
Wolfram Sang fbae3fb154 i2c: Remove all i2c_set_clientdata(client, NULL) in drivers
I2C drivers can use the clientdata-pointer to point to private data. As I2C
devices are not really unregistered, but merely detached from their driver, it
used to be the drivers obligation to clear this pointer during remove() or a
failed probe(). As a couple of drivers forgot to do this, it was agreed that it
was cleaner if the i2c-core does this clearance when appropriate, as there is
no guarantee for the lifetime of the clientdata-pointer after remove() anyhow.
This feature was added to the core with commit
e4a7b9b04d to fix the faulty drivers.

As there is no need anymore to clear the clientdata-pointer, remove all current
occurrences in the drivers to simplify the code and prevent confusion.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Richard Purdie <rpurdie@linux.intel.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-06-03 11:33:58 +02:00

688 lines
17 KiB
C

/*
* Driver for Epson's RTC module RX-8025 SA/NB
*
* Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
*
* Copyright (C) 2005 by Digi International Inc.
* All rights reserved.
*
* Modified by fengjh at rising.com.cn
* <http://lists.lm-sensors.org/mailman/listinfo/lm-sensors>
* 2006.11
*
* Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com>
* Converted to new style by Wolfgang Grandegger <wg@grandegger.com>
* Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com>
*
* 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 <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/bcd.h>
#include <linux/i2c.h>
#include <linux/list.h>
#include <linux/rtc.h>
/* Register definitions */
#define RX8025_REG_SEC 0x00
#define RX8025_REG_MIN 0x01
#define RX8025_REG_HOUR 0x02
#define RX8025_REG_WDAY 0x03
#define RX8025_REG_MDAY 0x04
#define RX8025_REG_MONTH 0x05
#define RX8025_REG_YEAR 0x06
#define RX8025_REG_DIGOFF 0x07
#define RX8025_REG_ALWMIN 0x08
#define RX8025_REG_ALWHOUR 0x09
#define RX8025_REG_ALWWDAY 0x0a
#define RX8025_REG_ALDMIN 0x0b
#define RX8025_REG_ALDHOUR 0x0c
/* 0x0d is reserved */
#define RX8025_REG_CTRL1 0x0e
#define RX8025_REG_CTRL2 0x0f
#define RX8025_BIT_CTRL1_CT (7 << 0)
/* 1 Hz periodic level irq */
#define RX8025_BIT_CTRL1_CT_1HZ 4
#define RX8025_BIT_CTRL1_TEST (1 << 3)
#define RX8025_BIT_CTRL1_1224 (1 << 5)
#define RX8025_BIT_CTRL1_DALE (1 << 6)
#define RX8025_BIT_CTRL1_WALE (1 << 7)
#define RX8025_BIT_CTRL2_DAFG (1 << 0)
#define RX8025_BIT_CTRL2_WAFG (1 << 1)
#define RX8025_BIT_CTRL2_CTFG (1 << 2)
#define RX8025_BIT_CTRL2_PON (1 << 4)
#define RX8025_BIT_CTRL2_XST (1 << 5)
#define RX8025_BIT_CTRL2_VDET (1 << 6)
/* Clock precision adjustment */
#define RX8025_ADJ_RESOLUTION 3050 /* in ppb */
#define RX8025_ADJ_DATA_MAX 62
#define RX8025_ADJ_DATA_MIN -62
static const struct i2c_device_id rx8025_id[] = {
{ "rx8025", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, rx8025_id);
struct rx8025_data {
struct i2c_client *client;
struct rtc_device *rtc;
struct work_struct work;
u8 ctrl1;
unsigned exiting:1;
};
static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value)
{
int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08);
if (ret < 0) {
dev_err(&client->dev, "Unable to read register #%d\n", number);
return ret;
}
*value = ret;
return 0;
}
static int rx8025_read_regs(struct i2c_client *client,
int number, u8 length, u8 *values)
{
int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08,
length, values);
if (ret != length) {
dev_err(&client->dev, "Unable to read registers #%d..#%d\n",
number, number + length - 1);
return ret < 0 ? ret : -EIO;
}
return 0;
}
static int rx8025_write_reg(struct i2c_client *client, int number, u8 value)
{
int ret = i2c_smbus_write_byte_data(client, number << 4, value);
if (ret)
dev_err(&client->dev, "Unable to write register #%d\n",
number);
return ret;
}
static int rx8025_write_regs(struct i2c_client *client,
int number, u8 length, u8 *values)
{
int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08,
length, values);
if (ret)
dev_err(&client->dev, "Unable to write registers #%d..#%d\n",
number, number + length - 1);
return ret;
}
static irqreturn_t rx8025_irq(int irq, void *dev_id)
{
struct i2c_client *client = dev_id;
struct rx8025_data *rx8025 = i2c_get_clientdata(client);
disable_irq_nosync(irq);
schedule_work(&rx8025->work);
return IRQ_HANDLED;
}
static void rx8025_work(struct work_struct *work)
{
struct rx8025_data *rx8025 = container_of(work, struct rx8025_data,
work);
struct i2c_client *client = rx8025->client;
struct mutex *lock = &rx8025->rtc->ops_lock;
u8 status;
mutex_lock(lock);
if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status))
goto out;
if (!(status & RX8025_BIT_CTRL2_XST))
dev_warn(&client->dev, "Oscillation stop was detected,"
"you may have to readjust the clock\n");
if (status & RX8025_BIT_CTRL2_CTFG) {
/* periodic */
status &= ~RX8025_BIT_CTRL2_CTFG;
local_irq_disable();
rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
local_irq_enable();
}
if (status & RX8025_BIT_CTRL2_DAFG) {
/* alarm */
status &= RX8025_BIT_CTRL2_DAFG;
if (rx8025_write_reg(client, RX8025_REG_CTRL1,
rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
goto out;
local_irq_disable();
rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
local_irq_enable();
}
/* acknowledge IRQ */
rx8025_write_reg(client, RX8025_REG_CTRL2,
status | RX8025_BIT_CTRL2_XST);
out:
if (!rx8025->exiting)
enable_irq(client->irq);
mutex_unlock(lock);
}
static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
{
struct rx8025_data *rx8025 = dev_get_drvdata(dev);
u8 date[7];
int err;
err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date);
if (err)
return err;
dev_dbg(dev, "%s: read 0x%02x 0x%02x "
"0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__,
date[0], date[1], date[2], date[3], date[4],
date[5], date[6]);
dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
else
dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
+ (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]);
if (dt->tm_year < 70)
dt->tm_year += 100;
dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__,
dt->tm_sec, dt->tm_min, dt->tm_hour,
dt->tm_mday, dt->tm_mon, dt->tm_year);
return rtc_valid_tm(dt);
}
static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
{
struct rx8025_data *rx8025 = dev_get_drvdata(dev);
u8 date[7];
/*
* BUG: The HW assumes every year that is a multiple of 4 to be a leap
* year. Next time this is wrong is 2100, which will not be a leap
* year.
*/
/*
* Here the read-only bits are written as "0". I'm not sure if that
* is sound.
*/
date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
else
date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
| bin2bcd((dt->tm_hour + 11) % 12 + 1);
date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100);
dev_dbg(dev,
"%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n",
__func__,
date[0], date[1], date[2], date[3], date[4], date[5], date[6]);
return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date);
}
static int rx8025_init_client(struct i2c_client *client, int *need_reset)
{
struct rx8025_data *rx8025 = i2c_get_clientdata(client);
u8 ctrl[2], ctrl2;
int need_clear = 0;
int err;
err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl);
if (err)
goto out;
/* Keep test bit zero ! */
rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
if (ctrl[1] & RX8025_BIT_CTRL2_PON) {
dev_warn(&client->dev, "power-on reset was detected, "
"you may have to readjust the clock\n");
*need_reset = 1;
}
if (ctrl[1] & RX8025_BIT_CTRL2_VDET) {
dev_warn(&client->dev, "a power voltage drop was detected, "
"you may have to readjust the clock\n");
*need_reset = 1;
}
if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) {
dev_warn(&client->dev, "Oscillation stop was detected,"
"you may have to readjust the clock\n");
*need_reset = 1;
}
if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
dev_warn(&client->dev, "Alarm was detected\n");
need_clear = 1;
}
if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG))
need_clear = 1;
if (*need_reset || need_clear) {
ctrl2 = ctrl[0];
ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET |
RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
RX8025_BIT_CTRL2_DAFG);
ctrl2 |= RX8025_BIT_CTRL2_XST;
err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
}
out:
return err;
}
/* Alarm support */
static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
{
struct rx8025_data *rx8025 = dev_get_drvdata(dev);
struct i2c_client *client = rx8025->client;
u8 ctrl2, ald[2];
int err;
if (client->irq <= 0)
return -EINVAL;
err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
if (err)
return err;
err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2);
if (err)
return err;
dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
__func__, ald[0], ald[1], ctrl2);
/* Hardware alarms precision is 1 minute! */
t->time.tm_sec = 0;
t->time.tm_min = bcd2bin(ald[0] & 0x7f);
if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
else
t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
+ (ald[1] & 0x20 ? 12 : 0);
t->time.tm_wday = -1;
t->time.tm_mday = -1;
t->time.tm_mon = -1;
t->time.tm_year = -1;
dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n",
__func__,
t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
t->time.tm_mday, t->time.tm_mon, t->time.tm_year);
t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
return err;
}
static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
{
struct i2c_client *client = to_i2c_client(dev);
struct rx8025_data *rx8025 = dev_get_drvdata(dev);
u8 ald[2];
int err;
if (client->irq <= 0)
return -EINVAL;
/* Hardware alarm precision is 1 minute! */
ald[0] = bin2bcd(t->time.tm_min);
if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
ald[1] = bin2bcd(t->time.tm_hour);
else
ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
| bin2bcd((t->time.tm_hour + 11) % 12 + 1);
dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
rx8025->ctrl1);
if (err)
return err;
}
err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald);
if (err)
return err;
if (t->enabled) {
rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
rx8025->ctrl1);
if (err)
return err;
}
return 0;
}
static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct rx8025_data *rx8025 = dev_get_drvdata(dev);
u8 ctrl1;
int err;
ctrl1 = rx8025->ctrl1;
if (enabled)
ctrl1 |= RX8025_BIT_CTRL1_DALE;
else
ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
if (ctrl1 != rx8025->ctrl1) {
rx8025->ctrl1 = ctrl1;
err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
rx8025->ctrl1);
if (err)
return err;
}
return 0;
}
static int rx8025_irq_set_state(struct device *dev, int enabled)
{
struct i2c_client *client = to_i2c_client(dev);
struct rx8025_data *rx8025 = i2c_get_clientdata(client);
int ctrl1;
int err;
if (client->irq <= 0)
return -ENXIO;
ctrl1 = rx8025->ctrl1 & ~RX8025_BIT_CTRL1_CT;
if (enabled)
ctrl1 |= RX8025_BIT_CTRL1_CT_1HZ;
if (ctrl1 != rx8025->ctrl1) {
rx8025->ctrl1 = ctrl1;
err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
rx8025->ctrl1);
if (err)
return err;
}
return 0;
}
static struct rtc_class_ops rx8025_rtc_ops = {
.read_time = rx8025_get_time,
.set_time = rx8025_set_time,
.read_alarm = rx8025_read_alarm,
.set_alarm = rx8025_set_alarm,
.alarm_irq_enable = rx8025_alarm_irq_enable,
.irq_set_state = rx8025_irq_set_state,
};
/*
* Clock precision adjustment support
*
* According to the RX8025 SA/NB application manual the frequency and
* temperature charateristics can be approximated using the following
* equation:
*
* df = a * (ut - t)**2
*
* df: Frequency deviation in any temperature
* a : Coefficient = (-35 +-5) * 10**-9
* ut: Ultimate temperature in degree = +25 +-5 degree
* t : Any temperature in degree
*
* Note that the clock adjustment in ppb must be entered (which is
* the negative value of the deviation).
*/
static int rx8025_get_clock_adjust(struct device *dev, int *adj)
{
struct i2c_client *client = to_i2c_client(dev);
u8 digoff;
int err;
err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff);
if (err)
return err;
*adj = digoff >= 64 ? digoff - 128 : digoff;
if (*adj > 0)
(*adj)--;
*adj *= -RX8025_ADJ_RESOLUTION;
return 0;
}
static int rx8025_set_clock_adjust(struct device *dev, int adj)
{
struct i2c_client *client = to_i2c_client(dev);
u8 digoff;
int err;
adj /= -RX8025_ADJ_RESOLUTION;
if (adj > RX8025_ADJ_DATA_MAX)
adj = RX8025_ADJ_DATA_MAX;
else if (adj < RX8025_ADJ_DATA_MIN)
adj = RX8025_ADJ_DATA_MIN;
else if (adj > 0)
adj++;
else if (adj < 0)
adj += 128;
digoff = adj;
err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
if (err)
return err;
dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
return 0;
}
static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int err, adj;
err = rx8025_get_clock_adjust(dev, &adj);
if (err)
return err;
return sprintf(buf, "%d\n", adj);
}
static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
int adj, err;
if (sscanf(buf, "%i", &adj) != 1)
return -EINVAL;
err = rx8025_set_clock_adjust(dev, adj);
return err ? err : count;
}
static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
rx8025_sysfs_show_clock_adjust,
rx8025_sysfs_store_clock_adjust);
static int rx8025_sysfs_register(struct device *dev)
{
return device_create_file(dev, &dev_attr_clock_adjust_ppb);
}
static void rx8025_sysfs_unregister(struct device *dev)
{
device_remove_file(dev, &dev_attr_clock_adjust_ppb);
}
static int __devinit rx8025_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
struct rx8025_data *rx8025;
int err, need_reset = 0;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_I2C_BLOCK)) {
dev_err(&adapter->dev,
"doesn't support required functionality\n");
err = -EIO;
goto errout;
}
rx8025 = kzalloc(sizeof(*rx8025), GFP_KERNEL);
if (!rx8025) {
dev_err(&adapter->dev, "failed to alloc memory\n");
err = -ENOMEM;
goto errout;
}
rx8025->client = client;
i2c_set_clientdata(client, rx8025);
INIT_WORK(&rx8025->work, rx8025_work);
err = rx8025_init_client(client, &need_reset);
if (err)
goto errout_free;
if (need_reset) {
struct rtc_time tm;
dev_info(&client->dev,
"bad conditions detected, resetting date\n");
rtc_time_to_tm(0, &tm); /* 1970/1/1 */
rx8025_set_time(&client->dev, &tm);
}
rx8025->rtc = rtc_device_register(client->name, &client->dev,
&rx8025_rtc_ops, THIS_MODULE);
if (IS_ERR(rx8025->rtc)) {
err = PTR_ERR(rx8025->rtc);
dev_err(&client->dev, "unable to register the class device\n");
goto errout_free;
}
if (client->irq > 0) {
dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
err = request_irq(client->irq, rx8025_irq,
0, "rx8025", client);
if (err) {
dev_err(&client->dev, "unable to request IRQ\n");
goto errout_reg;
}
}
rx8025->rtc->irq_freq = 1;
rx8025->rtc->max_user_freq = 1;
err = rx8025_sysfs_register(&client->dev);
if (err)
goto errout_irq;
return 0;
errout_irq:
if (client->irq > 0)
free_irq(client->irq, client);
errout_reg:
rtc_device_unregister(rx8025->rtc);
errout_free:
kfree(rx8025);
errout:
dev_err(&adapter->dev, "probing for rx8025 failed\n");
return err;
}
static int __devexit rx8025_remove(struct i2c_client *client)
{
struct rx8025_data *rx8025 = i2c_get_clientdata(client);
struct mutex *lock = &rx8025->rtc->ops_lock;
if (client->irq > 0) {
mutex_lock(lock);
rx8025->exiting = 1;
mutex_unlock(lock);
free_irq(client->irq, client);
flush_scheduled_work();
}
rx8025_sysfs_unregister(&client->dev);
rtc_device_unregister(rx8025->rtc);
kfree(rx8025);
return 0;
}
static struct i2c_driver rx8025_driver = {
.driver = {
.name = "rtc-rx8025",
.owner = THIS_MODULE,
},
.probe = rx8025_probe,
.remove = __devexit_p(rx8025_remove),
.id_table = rx8025_id,
};
static int __init rx8025_init(void)
{
return i2c_add_driver(&rx8025_driver);
}
static void __exit rx8025_exit(void)
{
i2c_del_driver(&rx8025_driver);
}
MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
MODULE_LICENSE("GPL");
module_init(rx8025_init);
module_exit(rx8025_exit);