Hi Guys
Any comments?
2013/7/11 James Lebron <leileishangchina@xxxxxxxxx>:
> Hi all
>
> I am still waiting for your response.....
>
> 2013/7/5 James Lebron <leileishangchina@xxxxxxxxx>:
>> Hi guys,
>>
>> Any comments?
>>
>> 2013/7/2 James Lebron <leileishangchina@xxxxxxxxx>:
>>> Hi Wolfram
>>>
>>> Have you finished reading datasheet?
>>>
>>> 2013/6/15 Wolfram Sang <wsa@xxxxxxxxxxxxx>:
>>>> 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 speed mode is hardware feature, you can't read it from
>>> software. It's similar to fast mode, and fast mode is set in platform
>>> data.
>>>
>>> The only method I can think of is to add a platform, like pxa910.
>>> And if you enable hs mode and platform is not pxa910, we'll set it to
>>> normal mode. Is this OK?
>>>
>>> 2. About hs mode clock setting. We don't know whether currently hs
>>> mode clock will be changed in future. Do you think below code is OK?
>>>
>>> if (i2c->rate)
>>> clk_set_rate(i2c->clk, i2c->rate);
>>> else
>>> clk_set_rate(i2c->clk, 62400000);
>>>
>>> pr_info("i2c: <%s> set rate to %ld\n",
>>> i2c->adap.name, clk_get_rate(i2c->clk));
>>>
>>>>> 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?
>>>>
>>>
>>> 3. Will fall back to normal mode when stop bit is sent.
>>>
>>>>>
>>>>> Signed-off-by: Leilei Shang <shangll@xxxxxxxxxxx>
>>>>
>>>> Which SoC supports this? I'd like to have a look at the datasheet.
>>>>
>>>> Thanks,
>>>>
>>>> Wolfram
>>>>
>>>
>>> Hope you can reply soon!
>>>
>>> Best regards
>>> Leilei
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