mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-28 20:02:17 +00:00
rtc-ds1307: true SMBus compatibility
Allow the rtc-ds1307 driver to work with SMBus controllers like nforce2 that do not support i2c block transfers. Signed-off-by: Ed Swierk <eswierk@aristanetworks.com> Acked-by: Jean Delvare <khali@linux-fr.org> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: BARRE Sebastien <sbarre@sdelcc.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
b250c96ea9
commit
30e7b039b1
1 changed files with 97 additions and 12 deletions
|
@ -94,6 +94,10 @@ struct ds1307 {
|
|||
struct i2c_client *client;
|
||||
struct rtc_device *rtc;
|
||||
struct work_struct work;
|
||||
s32 (*read_block_data)(struct i2c_client *client, u8 command,
|
||||
u8 length, u8 *values);
|
||||
s32 (*write_block_data)(struct i2c_client *client, u8 command,
|
||||
u8 length, const u8 *values);
|
||||
};
|
||||
|
||||
struct chip_desc {
|
||||
|
@ -132,6 +136,79 @@ MODULE_DEVICE_TABLE(i2c, ds1307_id);
|
|||
|
||||
/*----------------------------------------------------------------------*/
|
||||
|
||||
#define BLOCK_DATA_MAX_TRIES 10
|
||||
|
||||
static s32 ds1307_read_block_data_once(struct i2c_client *client, u8 command,
|
||||
u8 length, u8 *values)
|
||||
{
|
||||
s32 i, data;
|
||||
|
||||
for (i = 0; i < length; i++) {
|
||||
data = i2c_smbus_read_byte_data(client, command + i);
|
||||
if (data < 0)
|
||||
return data;
|
||||
values[i] = data;
|
||||
}
|
||||
return i;
|
||||
}
|
||||
|
||||
static s32 ds1307_read_block_data(struct i2c_client *client, u8 command,
|
||||
u8 length, u8 *values)
|
||||
{
|
||||
u8 oldvalues[I2C_SMBUS_BLOCK_MAX];
|
||||
s32 ret;
|
||||
int tries = 0;
|
||||
|
||||
dev_dbg(&client->dev, "ds1307_read_block_data (length=%d)\n", length);
|
||||
ret = ds1307_read_block_data_once(client, command, length, values);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
do {
|
||||
if (++tries > BLOCK_DATA_MAX_TRIES) {
|
||||
dev_err(&client->dev,
|
||||
"ds1307_read_block_data failed\n");
|
||||
return -EIO;
|
||||
}
|
||||
memcpy(oldvalues, values, length);
|
||||
ret = ds1307_read_block_data_once(client, command, length,
|
||||
values);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
} while (memcmp(oldvalues, values, length));
|
||||
return length;
|
||||
}
|
||||
|
||||
static s32 ds1307_write_block_data(struct i2c_client *client, u8 command,
|
||||
u8 length, const u8 *values)
|
||||
{
|
||||
u8 currvalues[I2C_SMBUS_BLOCK_MAX];
|
||||
int tries = 0;
|
||||
|
||||
dev_dbg(&client->dev, "ds1307_write_block_data (length=%d)\n", length);
|
||||
do {
|
||||
s32 i, ret;
|
||||
|
||||
if (++tries > BLOCK_DATA_MAX_TRIES) {
|
||||
dev_err(&client->dev,
|
||||
"ds1307_write_block_data failed\n");
|
||||
return -EIO;
|
||||
}
|
||||
for (i = 0; i < length; i++) {
|
||||
ret = i2c_smbus_write_byte_data(client, command + i,
|
||||
values[i]);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
}
|
||||
ret = ds1307_read_block_data_once(client, command, length,
|
||||
currvalues);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
} while (memcmp(currvalues, values, length));
|
||||
return length;
|
||||
}
|
||||
|
||||
/*----------------------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* The IRQ logic includes a "real" handler running in IRQ context just
|
||||
* long enough to schedule this workqueue entry. We need a task context
|
||||
|
@ -202,7 +279,7 @@ static int ds1307_get_time(struct device *dev, struct rtc_time *t)
|
|||
int tmp;
|
||||
|
||||
/* read the RTC date and time registers all at once */
|
||||
tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
|
||||
tmp = ds1307->read_block_data(ds1307->client,
|
||||
DS1307_REG_SECS, 7, ds1307->regs);
|
||||
if (tmp != 7) {
|
||||
dev_err(dev, "%s error %d\n", "read", tmp);
|
||||
|
@ -279,7 +356,7 @@ static int ds1307_set_time(struct device *dev, struct rtc_time *t)
|
|||
"write", buf[0], buf[1], buf[2], buf[3],
|
||||
buf[4], buf[5], buf[6]);
|
||||
|
||||
result = i2c_smbus_write_i2c_block_data(ds1307->client, 0, 7, buf);
|
||||
result = ds1307->write_block_data(ds1307->client, 0, 7, buf);
|
||||
if (result < 0) {
|
||||
dev_err(dev, "%s error %d\n", "write", result);
|
||||
return result;
|
||||
|
@ -297,7 +374,7 @@ static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
|
|||
return -EINVAL;
|
||||
|
||||
/* read all ALARM1, ALARM2, and status registers at once */
|
||||
ret = i2c_smbus_read_i2c_block_data(client,
|
||||
ret = ds1307->read_block_data(client,
|
||||
DS1339_REG_ALARM1_SECS, 9, ds1307->regs);
|
||||
if (ret != 9) {
|
||||
dev_err(dev, "%s error %d\n", "alarm read", ret);
|
||||
|
@ -356,7 +433,7 @@ static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
|
|||
t->enabled, t->pending);
|
||||
|
||||
/* read current status of both alarms and the chip */
|
||||
ret = i2c_smbus_read_i2c_block_data(client,
|
||||
ret = ds1307->read_block_data(client,
|
||||
DS1339_REG_ALARM1_SECS, 9, buf);
|
||||
if (ret != 9) {
|
||||
dev_err(dev, "%s error %d\n", "alarm write", ret);
|
||||
|
@ -391,7 +468,7 @@ static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
|
|||
}
|
||||
buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
|
||||
|
||||
ret = i2c_smbus_write_i2c_block_data(client,
|
||||
ret = ds1307->write_block_data(client,
|
||||
DS1339_REG_ALARM1_SECS, 9, buf);
|
||||
if (ret < 0) {
|
||||
dev_err(dev, "can't set alarm time\n");
|
||||
|
@ -479,7 +556,7 @@ ds1307_nvram_read(struct kobject *kobj, struct bin_attribute *attr,
|
|||
if (unlikely(!count))
|
||||
return count;
|
||||
|
||||
result = i2c_smbus_read_i2c_block_data(client, 8 + off, count, buf);
|
||||
result = ds1307->read_block_data(client, 8 + off, count, buf);
|
||||
if (result < 0)
|
||||
dev_err(&client->dev, "%s error %d\n", "nvram read", result);
|
||||
return result;
|
||||
|
@ -490,9 +567,11 @@ ds1307_nvram_write(struct kobject *kobj, struct bin_attribute *attr,
|
|||
char *buf, loff_t off, size_t count)
|
||||
{
|
||||
struct i2c_client *client;
|
||||
struct ds1307 *ds1307;
|
||||
int result;
|
||||
|
||||
client = kobj_to_i2c_client(kobj);
|
||||
ds1307 = i2c_get_clientdata(client);
|
||||
|
||||
if (unlikely(off >= NVRAM_SIZE))
|
||||
return -EFBIG;
|
||||
|
@ -501,7 +580,7 @@ ds1307_nvram_write(struct kobject *kobj, struct bin_attribute *attr,
|
|||
if (unlikely(!count))
|
||||
return count;
|
||||
|
||||
result = i2c_smbus_write_i2c_block_data(client, 8 + off, count, buf);
|
||||
result = ds1307->write_block_data(client, 8 + off, count, buf);
|
||||
if (result < 0) {
|
||||
dev_err(&client->dev, "%s error %d\n", "nvram write", result);
|
||||
return result;
|
||||
|
@ -535,9 +614,8 @@ static int __devinit ds1307_probe(struct i2c_client *client,
|
|||
int want_irq = false;
|
||||
unsigned char *buf;
|
||||
|
||||
if (!i2c_check_functionality(adapter,
|
||||
I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
|
||||
I2C_FUNC_SMBUS_I2C_BLOCK))
|
||||
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)
|
||||
&& !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
|
||||
return -EIO;
|
||||
|
||||
if (!(ds1307 = kzalloc(sizeof(struct ds1307), GFP_KERNEL)))
|
||||
|
@ -547,6 +625,13 @@ static int __devinit ds1307_probe(struct i2c_client *client,
|
|||
i2c_set_clientdata(client, ds1307);
|
||||
ds1307->type = id->driver_data;
|
||||
buf = ds1307->regs;
|
||||
if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) {
|
||||
ds1307->read_block_data = i2c_smbus_read_i2c_block_data;
|
||||
ds1307->write_block_data = i2c_smbus_write_i2c_block_data;
|
||||
} else {
|
||||
ds1307->read_block_data = ds1307_read_block_data;
|
||||
ds1307->write_block_data = ds1307_write_block_data;
|
||||
}
|
||||
|
||||
switch (ds1307->type) {
|
||||
case ds_1337:
|
||||
|
@ -557,7 +642,7 @@ static int __devinit ds1307_probe(struct i2c_client *client,
|
|||
want_irq = true;
|
||||
}
|
||||
/* get registers that the "rtc" read below won't read... */
|
||||
tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
|
||||
tmp = ds1307->read_block_data(ds1307->client,
|
||||
DS1337_REG_CONTROL, 2, buf);
|
||||
if (tmp != 2) {
|
||||
pr_debug("read error %d\n", tmp);
|
||||
|
@ -595,7 +680,7 @@ static int __devinit ds1307_probe(struct i2c_client *client,
|
|||
|
||||
read_rtc:
|
||||
/* read RTC registers */
|
||||
tmp = i2c_smbus_read_i2c_block_data(ds1307->client, 0, 8, buf);
|
||||
tmp = ds1307->read_block_data(ds1307->client, 0, 8, buf);
|
||||
if (tmp != 8) {
|
||||
pr_debug("read error %d\n", tmp);
|
||||
err = -EIO;
|
||||
|
|
Loading…
Reference in a new issue