[U-Boot] [PATCH v3] dm: usb: Copy over usb_device values from usb_scan_device() to final usb_device

[Simon Glass]

On 4 May 2015 at 11:19, Hans de Goede <hdegoede at redhat.com> wrote:
> Currently we copy over a number of usb_device values stored in the on stack
> struct usb_device probed in usb_scan_device() to the final driver-model managed
> struct usb_device in usb_child_pre_probe() through usb_device_platdata, and
> then call usb_select_config() to fill in the rest.
>
> There are 3 problems with this approach:
>
> 1) It does not fill in enough fields before calling usb_select_config(),
> specifically it does not fill in ep0's maxpacketsize causing a div by zero
> exception in the ehci driver.
>
> 2) It unnecessarily redoes a number of usb requests making usb probing slower
>
> 3) Calling usb_select_config() a second time fails on some usb-1 devices
> plugged into usb-2 hubs, causing u-boot to not recognize these devices.
>
> This commit fixes these issues by removing the usb_select_config() call from
> usb_child_pre_probe(), and instead of copying over things field by field
> through usb_device_platdata, store a pointer to the in stack usb_device
> (which is still valid when usb_child_pre_probe() gets called) and copy
> over the entire struct.
>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>

Acked-by: Simon Glass <sjg at chromium.org>