[rtc-linux] [PATCH] RTC driver(Linux) for PT7C4338 chip.

[Jain Priyanka-B32167]

Hi Wolfram, 


> -----Original Message-----
> From: Wolfram Sang [mailto:w.sang at pengutronix.de]
> Sent: Thursday, March 10, 2011 2:24 PM
> To: Jain Priyanka-B32167
> Cc: rtc-linux at googlegroups.com; linuxppc-dev at lists.ozlabs.org;
> a.zummo at towertech.it; p_gortmaker at yahoo.com; akpm at linux-foundation.org
> Subject: Re: [rtc-linux] [PATCH] RTC driver(Linux) for PT7C4338 chip.
> 
> Hi Priyanka,
> 
> > Though register-set looks identical but features were different.
> 
> Can you tell what exactly is different?
I will check both the devices data sheets again in detail and will get back on this.
> 
> > And also manufacturer is different.
> 
> That does not matter. If you look at ds_type, there are already different
> manufacturers. They will be correctly distinguished by i2c_device_id. The
> name of the driver itself is, well, just a name.
> 
> > But still it might be possible that we can reuse ds1307.c with some
> > modification.
> 
> I agree. The driver already supports some variants. Adding one more
> should not hurt. See 97f902b7be4dd6ba03c6aa8d3400783ed687ebd1 for an
> example which added ds3231 support.
> 
> > But if I look at the drivers present in drivers/rtc folder. Most of
> > them looks similar but still there are different drivers for different
> > chips.
> 
> Yes, it probably could be cleaned up if somebody had the time/hardware.
> 
> > Please suggest which way is more preferred: modifying existing
> > drivers(of different manufacturer) or writing new driver.
> 
> Ususally avoiding code duplication is good, it reduces maintenance
> burden. However, if adding the support turns out to make the original
> code unreadable or hard to follow, a new driver might be justified. This
> is why it is important to understand the differences of the chip as a
> first step. (I have the feeling, that modifying is the way to go here,
> though).
> 

I will explore possibility of using ds1307 driver for this.


Thanks
Priyanka