Re: [PATCH 2/3] usb: chipidea: host: let the hcd know's parent device node
From: Peter Chen <hidden>
Date: 2016-03-04 01:53:26
Also in:
linux-arm-kernel
On Thu, Mar 03, 2016 at 03:42:47PM +0100, Andrew Lunn wrote:
On Thu, Mar 03, 2016 at 06:01:15PM +0800, Peter Chen wrote:quoted
From: Peter Chen <redacted> 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 <redacted> --- 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?
This is only for chipidea driver whose host controller device doesn't have entry at dts, but other host controller driver which supports device tree should have its entry at dts.
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.
The controller device is the root for USB device, the common USB code will not touch its glue layer device (controller's parent). -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html