[i2c] PCF8563 doesn't pass validation check

[Laurent Pinchart]

Hi everybody,

I'm having issues with the PCF8563 RTC chip.

The Linux driver tries to validate the chip by checking if the BCD-coded time and date registers contain valid values.

When a low voltage condition is detected, the registers are not guaranteed to contain valid values. Experimentation showed that while the seconds, minutes, hours and day of the week registers didn't cause any issue, the months register could get out of the 01-12 range.

Has anyone experienced the same issue ? Would it be acceptable to remove the months register check ?

I've contacted NXP to get more information about what the chip guarantees and what it doesn't. I haven't had any answer yet but I expect them to tell me there is no guarantee at all.

Best regards,

-- 
Laurent Pinchart
CSE Semaphore Belgium

Chaussee de Bruxelles, 732A
B-1410 Waterloo
Belgium

T +32 (2) 387 42 59
F +32 (2) 387 42 75
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