redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

rtc: pcf8563: return meaningful value for RTC_VL_READ

Browse source 
PCF8563_SC_LV means the voltage dropped too low and data has been lost.

Link: https://lore.kernel.org/r/20191214220259.621996-10-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Alexandre Belloni 2019-12-14 23:02:51 +01:00
parent 935272aade
commit b371b10e94
1 changed files with 3 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
drivers/rtc/rtc-pcf8563.c
View file

@ -277,20 +277,16 @@ static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm)
static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
struct i2c_client *client = to_i2c_client(dev);
int vl, ret;
int ret;
switch (cmd) {
case RTC_VL_READ:
ret = i2c_smbus_read_byte_data(client, PCF8563_REG_SC);
if (ret < 0)
return ret;
vl = ret & PCF8563_SC_LV ? 1 : 0;
if (copy_to_user((void __user *)arg, &vl, sizeof(int)))
return -EFAULT;
return 0;
return put_user(ret & PCF8563_SC_LV ? RTC_VL_DATA_INVALID : 0,
(unsigned int __user *)arg);
default:
return -ENOIOCTLCMD;
}