Re: [PATCH 2/3] can: c_can: Provide generic interface to configure c-can message objects

[Amit Virdi <amit.virdi@st.com>]

On 1/16/2013 2:33 PM, Wolfgang Grandegger wrote:
> On 01/16/2013 08:45 AM, Amit Virdi wrote:
>> On 12/21/2012 1:43 AM, Wolfgang Grandegger wrote:
>>> On 12/20/2012 03:04 PM, Marc Kleine-Budde wrote:
>>>> On 12/20/2012 11:05 AM, Amit Virdi wrote:
>>>>> Depending on the underlying platform, the configuration of the c-can
>>>>> message objects can change. For e.g. in some systems, it makes more
>>>>> sense to receive many message objects and transmit very few. In any
>>>>> case, providing flexibility in configuring the message objects is
>>>>> highly
>>>>> desirable.
>>>>>
>>>>> The total number of message objects for C_CAN controller is fixed at
>>>>> 32.
>>>>> The receive message objects are assigned higher priority so they begin
>>>>> with message object#1. So, in order to configure the message object the
>>>>> driver just needs two parameters - rx_split (for differentiating
>>>>> between
>>>>> lower bucket and higher bucket) and tx_num.
>>>>>
>>>>> However, if the user doesn't specify these parameters, then the message
>>>>> objects are configured with default parameters with equal distribution
>>>>> of receive and transmit message objects (16 each).
>>>>
>>>> As Wolfgang pointed out, the DT should only describe the hardware. In
>>>> the ethernet world I think there is ethtool to configure the hardware.
>>>> Maybe we need something similar for CAN (or add CAN support to ethtool).
>>>
>>> Yeah, a simple tool using simple ioctl request would be nice, indeed.
>>> Well, as a per device setting seems overkill a simple module parameter
>>> would just do it.
>>>
>>
>> So, you're saying to drop the device configuration from the DT and use
>> some tool to do that. This would be nice if there are enough devices,
>> apart from the Bosch C-CAN controller, which require this sort of
>> configuration.
>
> No, I said: "a simple module parameter would just do it".
>

Ok, now I understood!

Regards
Amit Virdi