c62c1433e7
Windows and Linux host during enumeration requests device descriptor with request size set to 64 bytes when device was in default state (no address). Those systems do not want 64 bytes though since usb descriptors is only 18 bytes long so they silently expect that only one packet will be received possibly 18 bytes for EPS > 16 or 8 or 16 bytes for smaller EP0. For devices with CFG_TUD_ENDPOINT0_SIZE size 8 or 16 there was workaround that reduced request size to CFG_TUD_ENDPOINT0_SIZE and that was enough to satisfy Windows and Linux hosts. However USBCV testing application also requests device descriptor but with size set to 18 bytes. Workaround for Window/Linux prevented USBVC to tests devices with 8 bytes EP0 size since it send only 8 bytes while application did wanted 18 bytes. Solution that satisfies both cases it to check if in default state device descriptor request wants more bytes than descriptor size (18). If so host is expecting to receive less bytes then requested and workaround would be applied since Linux/Windows only try to read one packet. If 18 bytes was requested as is the case for USBCV, core returns descriptor in 2 or 3 packets as application expects. |
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| .. | ||
| dcd.h | ||
| dcd_attr.h | ||
| usbd.c | ||
| usbd.h | ||
| usbd_control.c | ||
| usbd_pvt.h | ||