The flag reported on the RTC_READ_VL ioctl is only initialized when the date is read out. So the voltage low value doesn't represent reality but the status at the time the date was read (or 0 if the date was not read yet).
Moreover when userspace requests a value via an ioctl there is no added benefit to also make a prosa representation of this (and other) values appear in the kernel log so remove the calls to dev_info and the driver data members to track their state. Signed-off-by: Uwe Kleine-König <[email protected]> --- Notes: While this is a fix I don't think it is critical enough to backport it to stable (or apply it during the rc phase). Looking at http://codesearch.debian.net/perpackage-results/RTC_VL_READ this ioctl isn't used much. drivers/rtc/rtc-pcf2127.c | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 4c7738f706c1..4f66c4216b5a 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -39,8 +39,6 @@ static struct i2c_driver pcf2127_driver; struct pcf2127 { struct rtc_device *rtc; - int voltage_low; /* indicates if a low_voltage was detected */ - int oscillator_failed; /* OSF was detected and date is unreliable */ }; /* @@ -49,7 +47,6 @@ struct pcf2127 { */ static int pcf2127_get_datetime(struct i2c_client *client, struct rtc_time *tm) { - struct pcf2127 *pcf2127 = i2c_get_clientdata(client); unsigned char buf[10] = { PCF2127_REG_CTRL1 }; /* read registers */ @@ -59,18 +56,15 @@ static int pcf2127_get_datetime(struct i2c_client *client, struct rtc_time *tm) return -EIO; } - if (buf[PCF2127_REG_CTRL3] & 0x04) { - pcf2127->voltage_low = 1; + if (buf[PCF2127_REG_CTRL3] & 0x04) dev_info(&client->dev, "low voltage detected, check/replace RTC battery.\n"); - } if (buf[PCF2127_REG_SC] & PCF2127_OSF) { /* * no need clear the flag here, * it will be cleared once the new date is saved */ - pcf2127->oscillator_failed = 1; dev_warn(&client->dev, "oscillator stop detected, date/time is not reliable\n"); return -EINVAL; @@ -107,7 +101,6 @@ static int pcf2127_get_datetime(struct i2c_client *client, struct rtc_time *tm) static int pcf2127_set_datetime(struct i2c_client *client, struct rtc_time *tm) { - struct pcf2127 *pcf2127 = i2c_get_clientdata(client); unsigned char buf[8]; int i = 0, err; @@ -141,9 +134,6 @@ static int pcf2127_set_datetime(struct i2c_client *client, struct rtc_time *tm) return -EIO; } - /* clear OSF flag in client data */ - pcf2127->oscillator_failed = 0; - return 0; } @@ -151,17 +141,27 @@ static int pcf2127_set_datetime(struct i2c_client *client, struct rtc_time *tm) static int pcf2127_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { - struct pcf2127 *pcf2127 = i2c_get_clientdata(to_i2c_client(dev)); + struct i2c_client *client = to_i2c_client(dev); + unsigned char buf = PCF2127_REG_CTRL3; + int ret; switch (cmd) { case RTC_VL_READ: - if (pcf2127->voltage_low) - dev_info(dev, "low voltage detected, check/replace battery\n"); - if (pcf2127->oscillator_failed) - dev_info(dev, "oscillator stop detected, date/time is not reliable\n"); + ret = i2c_master_send(client, &buf, 1); + if (!ret) + ret = -EIO; + if (ret < 0) + return ret; + + ret = i2c_master_recv(client, &buf, 1); + if (!ret) + ret = -EIO; + if (ret < 0) + return ret; + + buf = buf & PCF2127_REG_CTRL3_BLF ? 1 : 0; - if (copy_to_user((void __user *)arg, &pcf2127->voltage_low, - sizeof(int))) + if (copy_to_user((void __user *)arg, &buf, sizeof(int))) return -EFAULT; return 0; default: -- 2.6.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
