[PATCH 2/3] usb: chipidea: host: let the hcd know's parent device node

[andrew@lunn.ch (Andrew Lunn)]

On Thu, Mar 03, 2016 at 06:01:15PM +0800, Peter Chen wrote:
> From: Peter Chen <peter.chen@freescale.com>
> 
> Since the hcd (chipidea core device) has no device node, so
> if we want to describe the child node under the hcd, we had
> to put it under its parent's node (glue layer device), and
> in the code, we need to let the hcd knows glue layer's code,
> then the USB core can handle this node.
> 
> Signed-off-by: Peter Chen <peter.chen@freescale.com>
> ---
>  drivers/usb/chipidea/host.c | 18 ++++++++++++++----
>  1 file changed, 14 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
> index 053bac9..55120ef 100644
> --- a/drivers/usb/chipidea/host.c
> +++ b/drivers/usb/chipidea/host.c
> @@ -109,15 +109,25 @@ static int host_start(struct ci_hdrc *ci)
>  	struct ehci_hcd *ehci;
>  	struct ehci_ci_priv *priv;
>  	int ret;
> +	struct device *dev = ci->dev;
>  
> -	if (usb_disabled())
> +	if (usb_disabled() || !dev)
>  		return -ENODEV;
>  
> -	hcd = usb_create_hcd(&ci_ehci_hc_driver, ci->dev, dev_name(ci->dev));
> +	/*
> +	 * USB Core will try to get child node under roothub,
> +	 * but chipidea core has no of_node, and the child node
> +	 * for controller is located at glue layer's node which
> +	 * is chipidea core's parent.
> +	 */
> +	if (dev->parent && dev->parent->of_node)
> +		dev->of_node = dev->parent->of_node;

Is this a good idea? Two devices with the same of_node?

I know the networking code assumes of_node values are unique, and uses
it to find a device. Are you 100% sure the USB code does not make this
assumption.

	Andrew