diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index c6a0e54e6..3c5b4cb78 100755 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -1968,8 +1968,20 @@ unknown: memset(buf, 0, w_length); buf[5] = 0x01; switch (ctrl->bRequestType & USB_RECIP_MASK) { + /* + * The Microsoft CompatID OS Descriptor Spec(w_index = 0x4) and + * Extended Prop OS Desc Spec(w_index = 0x5) state that the + * HighByte of wValue is the InterfaceNumber and the LowByte is + * the PageNumber. This high/low byte ordering is incorrectly + * documented in the Spec. USB analyzer output on the below + * request packets show the high/low byte inverted i.e LowByte + * is the InterfaceNumber and the HighByte is the PageNumber. + * Since we dont support >64KB CompatID/ExtendedProp descriptors, + * PageNumber is set to 0. Hence verify that the HighByte is 0 + * for below two cases. + */ case USB_RECIP_DEVICE: - if (w_index != 0x4 || (w_value & 0xff)) + if (w_index != 0x4 || (w_value >> 8)) break; buf[6] = w_index; /* Number of ext compat interfaces */ @@ -1985,9 +1997,9 @@ unknown: } break; case USB_RECIP_INTERFACE: - if (w_index != 0x5 || (w_value & 0xff)) + if (w_index != 0x5 || (w_value >> 8)) break; - interface = w_value >> 8; + interface = w_value & 0xFF; if (interface >= MAX_CONFIG_INTERFACES || !os_desc_cfg->interface[interface]) break;