Re: [PATCH] i2c: pxa: enable high speed mode for i2c bus

[Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>]

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Hi,

On Fri, Jun 07, 2013 at 02:38:17PM +0800, Leilei Shang wrote:
> To enter high speed mode, following steps should be done:
> 1. When running in high speed mode, i2c clock rate is different
> from standard mode. Clock rate must be set according to
> specification first.
> 2. When i2c controller sends a master code and wins arbitration,
> high speed mode is entered.
> 
> If you want to enable high speed mode, the following members of
> platform data should be set to proper value:

I couldn't find any support for hs-mode in pxa2xx and pxa3xx. So it
shouldn't be set in platform data, but depending on checks if this is
supported on this device at all. And why don't simply switch to it if
rate is bigger than what is supported without hs-mode?

> 1. "high_mode" should be set to "1".
> 2. "master_code" should be set to "8'b 0000_1xxx"(x is 0 or 1).
>    If no master_code is set, set to default value 0xe.
> 3. "rate" should be set according to specification.

Note that you should fall back to full-speed mode after sending the stop
bit in high-speed mode. I can't find this in the code?

> 
> Signed-off-by: Leilei Shang <shangll-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>

Which SoC supports this? I'd like to have a look at the datasheet.

Thanks,

   Wolfram


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