Re: SPI: Add SPI driver for most known i.MX SoCs

[Julien Boibessot <julien.boibessot-GANU6spQydw@public.gmane.org>]

Hi Sascha,

Sascha Hauer a écrit :
> On Tue, Jun 02, 2009 at 10:13:22AM +0200, Julien Boibessot wrote:
>   
>> I don't know yet if it's related to bitbang but I would say that your  
>> driver is 2x slowier that current inkernel one.
>>     
>
> Have you checked that the driver gets the baudrate correct? If it is
> maybe my driver produces more interrupts than the in kernel driver.
> Maybe you could produce a defined workload with both drivers and compare
> the outputs of /proc/interrupts afterwards.
>   
Clock seems ok. The problem is the "setup" time between 2 transfers.
We use an ADC (MAX1027) from which we try to get the data as fast as 
possible (successive SPI read transfers of 16 bytes) and the time 
between 2 transfers was quite doubled when switching to your new driver.

I will try to spend more time to check that after the summer holidays ;-).

Regards,
Julien

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