Re: [PATCH 2/2] Add basic devices support for Nook Color

[Oleg Drokin <green@linuxhacker.ru>]

Hello!

On Apr 28, 2011, at 2:14 AM, Mike Rapoport wrote:
>>>> +static struct omap_musb_board_data musb_board_data = {
>>>> +	.interface_type		= MUSB_INTERFACE_ULPI,
>>>> +#ifdef CONFIG_USB_MUSB_OTG
>>>> +	.mode			= MUSB_OTG,
>>>> +#elif defined(CONFIG_USB_MUSB_HDRC_HCD)
>>>> +	.mode			= MUSB_HOST,
>>>> +#elif defined(CONFIG_USB_GADGET_MUSB_HDRC)
>>>> +	.mode			= MUSB_PERIPHERAL,
>>>> +#endif
>>> This kind of ifdefery is handled inside the musb driver. I'd set the mode to
>>> MUSB_OTG unless you want to explicitly limit it to HOST or PERIPHERAL
>> Actually it's not.
>> If I set MUSB_OTG here and then I choose PERIPHERAL mode in the kernel config,
>> the musb transceiver code will complain about board file and kernel config mismatch.
>> The Nook Color is advertised as peripheral device, but OTG must be working too
>> (not totally working at this point) I think there is value to be able to configure it
>> in two different modes.
> Frankly, I haven't tried choosing different modes in the kernel config and in
> the board data. Still, I believe that board data should define desired operation
> mode and the driver should do the best effort to enable the controller in the
> desired mode.

The desired operation mode is dependent on musb configuration.
E.g. see n8x0 board file for the example of the same thing.

Bye,
    Olg