This is a note to let you know that I've just added the patch titled USB: dummy-hcd: fix connection failures (wrong speed) to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From fe659bcc9b173bcfdd958ce2aec75e47651e74e1 Mon Sep 17 00:00:00 2001 From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Date: Tue, 26 Sep 2017 15:15:22 -0400 Subject: USB: dummy-hcd: fix connection failures (wrong speed) The dummy-hcd UDC driver is not careful about the way it handles connection speeds. It ignores the module parameter that is supposed to govern the maximum connection speed and it doesn't set the HCD flags properly for the case where it ends up running at full speed. The result is that in many cases, gadget enumeration over dummy-hcd fails because the bMaxPacketSize byte in the device descriptor is set incorrectly. For example, the default settings call for a high-speed connection, but the maxpacket value for ep0 ends up being set for a Super-Speed connection. This patch fixes the problem by initializing the gadget's max_speed and the HCD flags correctly. Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> CC: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> --- drivers/usb/gadget/udc/dummy_hcd.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c index b1e21b3be6e1..d515ec31afe4 100644 --- a/drivers/usb/gadget/udc/dummy_hcd.c +++ b/drivers/usb/gadget/udc/dummy_hcd.c @@ -1036,7 +1036,12 @@ static int dummy_udc_probe(struct platform_device *pdev) memzero_explicit(&dum->gadget, sizeof(struct usb_gadget)); dum->gadget.name = gadget_name; dum->gadget.ops = &dummy_ops; - dum->gadget.max_speed = USB_SPEED_SUPER; + if (mod_data.is_super_speed) + dum->gadget.max_speed = USB_SPEED_SUPER; + else if (mod_data.is_high_speed) + dum->gadget.max_speed = USB_SPEED_HIGH; + else + dum->gadget.max_speed = USB_SPEED_FULL; dum->gadget.dev.parent = &pdev->dev; init_dummy_udc_hw(dum); @@ -2560,8 +2565,6 @@ static struct hc_driver dummy_hcd = { .product_desc = "Dummy host controller", .hcd_priv_size = sizeof(struct dummy_hcd), - .flags = HCD_USB3 | HCD_SHARED, - .reset = dummy_setup, .start = dummy_start, .stop = dummy_stop, @@ -2590,8 +2593,12 @@ static int dummy_hcd_probe(struct platform_device *pdev) dev_info(&pdev->dev, "%s, driver " DRIVER_VERSION "\n", driver_desc); dum = *((void **)dev_get_platdata(&pdev->dev)); - if (!mod_data.is_super_speed) + if (mod_data.is_super_speed) + dummy_hcd.flags = HCD_USB3 | HCD_SHARED; + else if (mod_data.is_high_speed) dummy_hcd.flags = HCD_USB2; + else + dummy_hcd.flags = HCD_USB11; hs_hcd = usb_create_hcd(&dummy_hcd, &pdev->dev, dev_name(&pdev->dev)); if (!hs_hcd) return -ENOMEM; -- 2.14.1