RTC Epson Toyocom RX-8025T

RTC Epson Toyocom RX-8025T

[marcus.wolf]

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

Thanks a lot,

Marcus Wolf

Wolf-Entwicklungen
Helene-Lange-Weg 23
80637 München

Re: RTC Epson Toyocom RX-8025T

[Marcus Wolf]

Hi Alexandre,

yes, it looks like the programming interface of the 8801SA is identical
to the interface 8025T.

I will compile a kernel version with the rv8003 and check, if it works
next week. If it will, for sure we do not need a new driver.

Keep you tuned.

Marcus

Am 05.08.2019 um 15:16 schrieb Alexandre Belloni:
> On 05/08/2019 15:05:29+0200, Alexandre Belloni wrote:
>>> 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
>>
> 
> To elaborate, if this is the case, then the rv8803 should already work
> properly.
> 
> 

-- 
Marcus Wolf

Wolf-Entwicklungen
Helene-Lange-Weg 23
80637 München

Re: RTC Epson Toyocom RX-8025T

[Alexandre Belloni]

On 05/08/2019 15:05:29+0200, Alexandre Belloni wrote:
> > 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
> 

To elaborate, if this is the case, then the rv8803 should already work
properly.


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

Re: RTC Epson Toyocom RX-8025T

[Alexandre Belloni]

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