diff options
Diffstat (limited to 'drivers/usb/dwc3/gadget.c')
| -rw-r--r-- | drivers/usb/dwc3/gadget.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index f0a30ce0d2d6..6fbf461d523c 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2714,12 +2714,34 @@ int dwc3_gadget_init(struct dwc3 *dwc) } dwc->gadget.ops = &dwc3_gadget_ops; - dwc->gadget.max_speed = USB_SPEED_SUPER; dwc->gadget.speed = USB_SPEED_UNKNOWN; dwc->gadget.sg_supported = true; dwc->gadget.name = "dwc3-gadget"; /* + * FIXME We might be setting max_speed to <SUPER, however versions + * <2.20a of dwc3 have an issue with metastability (documented + * elsewhere in this driver) which tells us we can't set max speed to + * anything lower than SUPER. + * + * Because gadget.max_speed is only used by composite.c and function + * drivers (i.e. it won't go into dwc3's registers) we are allowing this + * to happen so we avoid sending SuperSpeed Capability descriptor + * together with our BOS descriptor as that could confuse host into + * thinking we can handle super speed. + * + * Note that, in fact, we won't even support GetBOS requests when speed + * is less than super speed because we don't have means, yet, to tell + * composite.c that we are USB 2.0 + LPM ECN. + */ + if (dwc->revision < DWC3_REVISION_220A) + dwc3_trace(trace_dwc3_gadget, + "Changing max_speed on rev %08x\n", + dwc->revision); + + dwc->gadget.max_speed = dwc->maximum_speed; + + /* * Per databook, DWC3 needs buffer size to be aligned to MaxPacketSize * on ep out. */ |