Re: invalid default values in RTC chip

From: Andrew Morton
Date: Thu Oct 16 2008 - 17:00:22 EST

On Tue, 14 Oct 2008 12:00:21 +0300
J__ri Reitel <juri.reitel@xxxxxxxxxxxxx> wrote:

> Hi,
> My question relates to RTC driver linux/drivers/rtc/rtc-ds1307.c for
> device m41t00. Driver probe function will fail if some of the chip's
> registers contain invalid date time values i.e. if month register is 32
> or minutes is 61. Is this correct behavior? Probe function's purpose is
> to check if the device is as was assumed (this time RTC and it is). The
> chip's values are incorrect but the chip works, even the m41t00 chip
> manual states that after initial powerup (RTC battery power applied)
> internal registers will contain random data.
> There are two solutions first is driver patch and another is i2c-dev and
> i2cset tool to use from user space during bootup. Whitch one should be used?

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