Re: [PATCH] 2.6 I2C epson 8564 RTC chip

[Russell King <rmk+lkml@arm.linux.org.uk>]

On Thu, Apr 29, 2004 at 01:41:23PM +0100, Ian Campbell wrote:
> Hi Stefan,
> 
> > This driver only does the low-level I2C stuff, the rtc misc device
> > driver is a separate driver module which I will send a patch for soon.
> 
> I have a patch (attached, it could do with cleaning up) for the Dallas
> DS1307 I2C RTC which I ported from the 2.4 rmk patch, originally written
> by Intrinsyc. Currently it includes both the I2C and the RTC bits in the
> same driver.

Have a look at drivers/acorn/char/{i2c,pcf8583}.[ch]

> Do you think it is realistic/possible to have the same generic RTC
> driver speak to multiple I2C devices, from what I can see in your driver
> the two chips seem pretty similar and the differences could probably be
> abstracted away. Perhaps that is your intention from the start?
> 
> I guess I will wait until you post the RTC misc driver and try and make
> the DS1307 one work with that before I submit it.

If you look at the last 2.6-rmk patch, you'll notice that it contains
an abstracted RTC driver - I got peed off with writing the same code
to support the user interfaces to the variety of RTCs over and over
again.  (Ones which are simple 32-bit second counters with alarms
through to ones which return D/M/Y H:M:S.C format.)

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core