Re: RTC Epson Toyocom RX-8025T

[Alexandre Belloni <alexandre.belloni@bootlin.com>]

Hi,

On 27/07/2019 10:48:06+0200, marcus.wolf@wolf-entwicklungen.de wrote:
> Hello Alessandro, hello Alexandre,
> 
> in a product of a customer of mine, the RX-8025T real time clock from Epson
> Toyocom is used.
> 
> My customer would like me to integrate the driver for this clock to mainline of
> the kernel.
> 
> At the moment, we have a seperate implementation, basing on the implemenattion
> of the existing RX-8025 driver.
> 
> Although the rtc of my customer has almost the same "name" as the one, the
> current driver is available for (just last letter differs), it works quite
> different. So for example I compared the registerset of the two clocks.Only 5
> of 16 registers are identical, 3 are very similar, but the other 8 are
> completely different. Also the functionality is quite different. Of course
> first of all, both are clocks, but all aditional features are not identical.
> The already supported SA type has two alarms - a day and a week alarm. The tyoe
> of my customer (t) just has one alarm, that can be switched to day and to week
> mode. In adition it has a timer and an 8bit RAM cell. In addition the protocol
> how to adress the registers on I2C is different....
> 
> Would you like me to propose you the support for the RX-8025T as a separate
> implementation - aka new driver?

I think that what you have is actually a RX-8801SA. Can you check that the
register layout is the same? The datasheet is available here:

https://support.epson.biz/td/api/doc_check.php?dl=app_RX-8801SA&lang=en

> On which base you'd like to see the patches? Head of mainline, last stable
> (5.2.2), or ....?
> 

v5.3-rc1 or rtc-next.


-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com