mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-15 08:44:14 +08:00
[PATCH] RTC subsystem: DS1672 oscillator handling
* Always enable the oscillator when we set the time * If the oscillator is disable when we probe the RTC report back a warning to the user * Added sysfs attribute to represent the state of the oscillator Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
parent
389ed39b97
commit
8a95b252d1
@ -23,6 +23,7 @@ I2C_CLIENT_INSMOD;
|
||||
|
||||
#define DS1672_REG_CNT_BASE 0
|
||||
#define DS1672_REG_CONTROL 4
|
||||
#define DS1672_REG_CONTROL_EOSC 0x80
|
||||
#define DS1672_REG_TRICKLE 5
|
||||
|
||||
|
||||
@ -72,16 +73,17 @@ static int ds1672_get_datetime(struct i2c_client *client, struct rtc_time *tm)
|
||||
static int ds1672_set_mmss(struct i2c_client *client, unsigned long secs)
|
||||
{
|
||||
int xfer;
|
||||
unsigned char buf[5];
|
||||
unsigned char buf[6];
|
||||
|
||||
buf[0] = DS1672_REG_CNT_BASE;
|
||||
buf[1] = secs & 0x000000FF;
|
||||
buf[2] = (secs & 0x0000FF00) >> 8;
|
||||
buf[3] = (secs & 0x00FF0000) >> 16;
|
||||
buf[4] = (secs & 0xFF000000) >> 24;
|
||||
buf[5] = 0; /* set control reg to enable counting */
|
||||
|
||||
xfer = i2c_master_send(client, buf, 5);
|
||||
if (xfer != 5) {
|
||||
xfer = i2c_master_send(client, buf, 6);
|
||||
if (xfer != 6) {
|
||||
dev_err(&client->dev, "%s: send: %d\n", __FUNCTION__, xfer);
|
||||
return -EIO;
|
||||
}
|
||||
@ -120,6 +122,44 @@ static int ds1672_rtc_set_mmss(struct device *dev, unsigned long secs)
|
||||
return ds1672_set_mmss(to_i2c_client(dev), secs);
|
||||
}
|
||||
|
||||
static int ds1672_get_control(struct i2c_client *client, u8 *status)
|
||||
{
|
||||
unsigned char addr = DS1672_REG_CONTROL;
|
||||
|
||||
struct i2c_msg msgs[] = {
|
||||
{ client->addr, 0, 1, &addr }, /* setup read ptr */
|
||||
{ client->addr, I2C_M_RD, 1, status }, /* read control */
|
||||
};
|
||||
|
||||
/* read control register */
|
||||
if ((i2c_transfer(client->adapter, &msgs[0], 2)) != 2) {
|
||||
dev_err(&client->dev, "%s: read error\n", __FUNCTION__);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* following are the sysfs callback functions */
|
||||
static ssize_t show_control(struct device *dev, struct device_attribute *attr, char *buf)
|
||||
{
|
||||
struct i2c_client *client = to_i2c_client(dev);
|
||||
char *state = "enabled";
|
||||
u8 control;
|
||||
int err;
|
||||
|
||||
err = ds1672_get_control(client, &control);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
if (control & DS1672_REG_CONTROL_EOSC)
|
||||
state = "disabled";
|
||||
|
||||
return sprintf(buf, "%s\n", state);
|
||||
}
|
||||
|
||||
static DEVICE_ATTR(control, S_IRUGO, show_control, NULL);
|
||||
|
||||
static struct rtc_class_ops ds1672_rtc_ops = {
|
||||
.read_time = ds1672_rtc_read_time,
|
||||
.set_time = ds1672_rtc_set_time,
|
||||
@ -162,6 +202,7 @@ static struct i2c_driver ds1672_driver = {
|
||||
static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind)
|
||||
{
|
||||
int err = 0;
|
||||
u8 control;
|
||||
struct i2c_client *client;
|
||||
struct rtc_device *rtc;
|
||||
|
||||
@ -202,6 +243,20 @@ static int ds1672_probe(struct i2c_adapter *adapter, int address, int kind)
|
||||
|
||||
i2c_set_clientdata(client, rtc);
|
||||
|
||||
/* read control register */
|
||||
err = ds1672_get_control(client, &control);
|
||||
if (err) {
|
||||
dev_err(&client->dev, "%s: read error\n", __FUNCTION__);
|
||||
goto exit_detach;
|
||||
}
|
||||
|
||||
if (control & DS1672_REG_CONTROL_EOSC)
|
||||
dev_warn(&client->dev, "Oscillator not enabled. "
|
||||
"Set time to enable.\n");
|
||||
|
||||
/* Register sysfs hooks */
|
||||
device_create_file(&client->dev, &dev_attr_control);
|
||||
|
||||
return 0;
|
||||
|
||||
exit_detach:
|
||||
|
Loading…
Reference in New Issue
Block a user