[PATCH] at91sam9g45: fix i2c bus speed
Nicolas Ferre
nicolas.ferre at atmel.com
Thu Sep 23 04:18:21 EDT 2010
Le 22/09/2010 11:31, Peter Korsgaard :
> Use a correct udelay value to get bus speed around 100KHz. The udelay
> value was most likely copied from the older devices, but the 9g45
> is signicantly faster (400MHz, DDR, ..), so a udelay of 2 gives a
> bus speed of around 190KHz, which is too fast for some devices.
> A udelay value of 5 gives a bus speed of around 90KHz here.
>
> Signed-off-by: Peter Korsgaard <jacmet at sunsite.dk>
> ---
> arch/arm/mach-at91/at91sam9g45_devices.c | 4 ++--
By the way, I suspect that at91sam9g20 has the same issue (400MHz core
also)...
We may also have a look at at91sam9g10 which embeds a 266MHz core....
[..]
Best regards,
--
Nicolas Ferre
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