[PATCH v3 1/1] USB: core: let USB device know device node

Arnd Bergmann arnd at arndb.de
Fri Jan 15 03:11:27 PST 2016


On Friday 15 January 2016 17:17:27 Peter Chen wrote:
> Although most of USB devices are hot-plug's, there are still some devices
> are hard wired on the board, eg, for HSIC and SSIC interface USB devices.
> If these kinds of USB devices are multiple functions, and they can supply
> other interfaces like i2c, gpios for other devices, we may need to
> describe these at device tree.
> 
> In this commit, it uses "reg" in dts as port number to match the port
> number decided by USB core, if they are the same, then the device node
> is for the device we are creating for USB core.
> 
> Signed-off-by: Peter Chen <peter.chen at freescale.com>

Acked-by: Arnd Bergmann <arnd at arndb.de>


Just one last question:

>  	dev->active_duration = -jiffies;
>  #endif
> -	if (root_hub)	/* Root hub always ok [and always wired] */
> +	if (root_hub) {	/* Root hub always ok [and always wired] */
>  		dev->authorized = 1;
> -	else {
> +		dev->of_node = bus->controller->of_node;


You are adding the of_node of the controller to the root hub, which I
guess means that we now have two 'struct device' instances with the
same of_node. They have different bus_types, so I think that is ok,
but I wonder if it would be better to leave out the of_node for the
root hub to avoid the confusion. Can you think of a case where we
actually want to add properties for the root hub that we can't do
more easily in the host controller?

	Arnd



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