Re: [PATCH] stmmac: Add support for SIMATIC IOT2000 platform

[Jan Kiszka]

On 2017-04-25 12:07, Jan Kiszka wrote:
> On 2017-04-25 11:46, Andy Shevchenko wrote:
>> On Tue, Apr 25, 2017 at 12:00 PM, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:
>>> On 2017-04-25 09:30, Andy Shevchenko wrote:
>>>> On Tue, Apr 25, 2017 at 8:44 AM, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:
>>>>> On 2017-04-24 23:27, Andy Shevchenko wrote:
>>>>>> On Mon, Apr 24, 2017 at 10:27 PM, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:
>>>>>>> The IOT2000 is industrial controller platform, derived from the Intel
>>>>>>> Galileo Gen2 board. The variant IOT2020 comes with one LAN port, the
>>>>>>> IOT2040 has two of them. They can be told apart based on the board asset
>>>>>>> tag in the DMI table.
>>>>
>>>>>>> +       const char *asset_tag;
>>>>>>
>>>>>> I guess this is redundant. See below.
>>>>>>
>>>>>>> +       {
>>>>>>> +               .name = "SIMATIC IOT2000",
>>>>>>> +               .asset_tag = "6ES7647-0AA00-0YA2",
>>>>>>> +               .func = 6,
>>>>>>> +               .phy_addr = 1,
>>>>>>> +       },
>>>>>>
>>>>>> The below has same definition disregard on asset_tag.
>>>>>>
>>>>>
>>>>> There is a small difference in the asset tag, just not at the last digit
>>>>> where one may expect it, look:
>>>>>
>>>>> ...-0YA2 -> IOT2020
>>>>> ...-1YA2 -> IOT2040
>>>>
>>>> Yes. And how does it change my statement? You may use one record here
>>>> instead of two.
>>>
>>> How? Please be more verbose in your comments.
>>
>>        {
>>                .name = "SIMATIC IOT2000",
>>                .func = 6,
>>                .phy_addr = 1,
>>        },
>>        {
>>                .name = "SIMATIC IOT2000",
>>                .func = 7,
>>                .phy_addr = 1,
>>        },
>>
>> That's all what you need.
> 
> Nope. Again: the asset tag is the way to tell both apart AND to ensure
> that we do not match on future devices.

To be more verbose: your version (which is our old one) would even
enable the second, not connected port on the IOT2020. Incorrectly. Plus
the risk to match different future devices.

Jan

-- 
Siemens AG, Corporate Technology, CT RDA ITP SES-DE
Corporate Competence Center Embedded Linux