[U-Boot] [PATCH] dm: usb: Fix divide by 0 errors in host drivers caused by not setting maxpsize

[Simon Glass]

On 29 April 2015 at 03:40, Hans de Goede <hdegoede at redhat.com> wrote:
> usb_child_pre_probe() initializes the final struct usb_device by redoingthe
> usb_select_config() done by usb_scan_device() but not the usb_prepare_device()
> call, this leads to a call into the hcd to get the device descriptors without
> ep0's maxpacketsize being set, which leads to a device by 0 error in the
> ehci driver.
>
> This commit fixes this by passing the maxpacketsize through the
> usb_device_platdata and setting it in usb_child_pre_probe().
>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
>  drivers/usb/host/usb-uclass.c | 4 ++++
>  include/usb.h                 | 3 +++
>  2 files changed, 7 insertions(+)

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

>
> diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c
> index 714bc0e..2af8611 100644
> --- a/drivers/usb/host/usb-uclass.c
> +++ b/drivers/usb/host/usb-uclass.c
> @@ -539,6 +539,7 @@ int usb_scan_device(struct udevice *parent, int port,
>         plat->speed = udev->speed;
>         plat->slot_id = udev->slot_id;
>         plat->portnr = port;
> +       plat->maxpacketsize = udev->maxpacketsize;
>         debug("** device '%s': stashing slot_id=%d\n", dev->name,
>               plat->slot_id);
>         priv->next_addr++;
> @@ -613,6 +614,9 @@ int usb_child_pre_probe(struct udevice *dev)
>         udev->slot_id = plat->slot_id;
>         udev->portnr = plat->portnr;
>         udev->speed = plat->speed;
> +       udev->maxpacketsize = plat->maxpacketsize;
> +       udev->epmaxpacketin[0] = 1 << (udev->maxpacketsize + 3);
> +       udev->epmaxpacketout[0] = 1 << (udev->maxpacketsize + 3);
>         debug("** device '%s': getting slot_id=%d\n", dev->name, plat->slot_id);
>
>         ret = usb_select_config(udev);
> diff --git a/include/usb.h b/include/usb.h
> index 1984e8f..a5eb7fe 100644
> --- a/include/usb.h
> +++ b/include/usb.h
> @@ -576,6 +576,7 @@ struct usb_platdata {
>   * @slot_id:   USB3 slot ID, which is separate from the device address
>   * @portnr:    Port number of this device on its parent hub, numbered from 1
>   *             (0 mean this device is the root hub)
> + * @maxpacketsize: EP0 maxpacketsize
>   * @strings:   List of descriptor strings (for sandbox emulation purposes)
>   * @desc_list: List of descriptors (for sandbox emulation purposes)
>   */
> @@ -585,6 +586,8 @@ struct usb_dev_platdata {
>         int devnum;
>         int slot_id;
>         int portnr;     /* Hub port number, 1..n */
> +       int maxpacketsize; /* Maximum packet size; one of: PACKET_SIZE_* */
> +
>  #ifdef CONFIG_SANDBOX
>         struct usb_string *strings;
>         /* NULL-terminated list of descriptor pointers */
> --
> 2.3.6
>