Correct endianness handling for big-endian hosts in SETUP packets#3595
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Correct endianness handling for big-endian hosts in SETUP packets#3595dangfan wants to merge 1 commit into
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…P packets USB wire format is little-endian, but TinyUSB assumed host byte order == little-endian in two places: 1. dcd_event_setup_received() (dcd.h): after memcpy-ing the raw SETUP bytes into tusb_control_request_t, wValue/wIndex/wLength were left in wire byte order. Fix: apply tu_le16toh() on each field. On LE hosts this is a no-op. 2. Bit-field structs (tusb_types.h): GCC on big-endian ARM allocates bit fields from the MSB downward, opposite to the USB spec's LSB-first numbering. Fix: reverse the field declaration order under TU_BIG_ENDIAN for tusb_desc_endpoint_t.bmAttributes and tusb_control_request_t.bmRequestType_bit. Tested on CIU98320B (big-endian ARM, full-speed device) with HID keyboard demo: full enumeration and keystroke transmission verified.
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USB wire format is little-endian, but TinyUSB assumed host byte order == little-endian
in two places:
dcd_event_setup_received() (dcd.h): after memcpy-ing the raw SETUP bytes into
tusb_control_request_t, wValue/wIndex/wLength were left in wire byte order.
Fix: apply tu_le16toh() on each field. On LE hosts this is a no-op.
Bit-field structs (tusb_types.h): GCC on big-endian ARM allocates bit fields
from the MSB downward, opposite to the USB spec's LSB-first numbering.
Fix: reverse the field declaration order under TU_BIG_ENDIAN for
tusb_desc_endpoint_t.bmAttributes and tusb_control_request_t.bmRequestType_bit.
Tested on HED CIU98320B (big-endian ARM, full-speed device) with HID keyboard demo:
full enumeration and keystroke transmission verified.