From a4f0927ef588cf62bb864707261482c874352942 Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Tue, 31 Oct 2017 15:56:29 +0200 Subject: [PATCH] usb: gadget: core: Fix ->udc_set_speed() speed handling Currently UDC core calls ->udc_set_speed() with the speed parameter containing the maximum speed supported by the gadget function driver. This might very well be more than that supported by the UDC controller driver. Select the lesser of the 2 speeds so both UDC and gadget function driver are operating within limits. This fixes PHY Erratic errors and 2 second enumeration delay on TI's AM437x platforms. Fixes: 6099eca796ae ("usb: gadget: core: introduce ->udc_set_speed() method") Cc: # v4.13+ Reported-by: Dylan Howey Signed-off-by: Roger Quadros Signed-off-by: Felipe Balbi --- drivers/usb/gadget/udc/core.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 61422d624ad0..93eff7dec2f5 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1069,8 +1069,12 @@ static inline void usb_gadget_udc_stop(struct usb_udc *udc) static inline void usb_gadget_udc_set_speed(struct usb_udc *udc, enum usb_device_speed speed) { - if (udc->gadget->ops->udc_set_speed) - udc->gadget->ops->udc_set_speed(udc->gadget, speed); + if (udc->gadget->ops->udc_set_speed) { + enum usb_device_speed s; + + s = min(speed, udc->gadget->max_speed); + udc->gadget->ops->udc_set_speed(udc->gadget, s); + } } /** -- GitLab