From 6e1140683140eb7bb80dfae0d207a920dec6d12c Mon Sep 17 00:00:00 2001 From: Reimu NotMoe Date: Fri, 27 Dec 2024 01:02:10 +0800 Subject: [PATCH] dcd_pic: handle EP0 timeout/stall correctly --- src/portable/microchip/pic/dcd_pic.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/src/portable/microchip/pic/dcd_pic.c b/src/portable/microchip/pic/dcd_pic.c index 04c54059f..4e0bd735e 100644 --- a/src/portable/microchip/pic/dcd_pic.c +++ b/src/portable/microchip/pic/dcd_pic.c @@ -316,12 +316,23 @@ static void prepare_next_setup_packet(uint8_t rhport) { const unsigned out_odd = _dcd.endpoint[0][0].odd; const unsigned in_odd = _dcd.endpoint[0][1].odd; - TU_ASSERT(0 == _dcd.bdt[0][0][out_odd].own, ); + + // Abandon any previous control transfers that might have been using EP0. + // Ordinarily, nothing actually needs abandoning, since the previous control + // transfer would have completed successfully prior to the host sending the + // next SETUP packet. However, in a timeout error case, or after an EP0 + // STALL event, one or more UOWN bits might still be set. If so, we should + // clear the UOWN bits, so the EP0 IN/OUT endpoints are in a known inactive + // state, ready for re-arming by the `dcd_edpt_xfer' function that will be + // called next. _dcd.bdt[0][0][out_odd].data = 0; + _dcd.bdt[0][0][out_odd].own = 0; _dcd.bdt[0][0][out_odd ^ 1].data = 1; _dcd.bdt[0][1][in_odd].data = 1; + _dcd.bdt[0][1][in_odd].own = 0; _dcd.bdt[0][1][in_odd ^ 1].data = 0; + _dcd.bdt[0][1][in_odd ^ 1].own = 0; dcd_edpt_xfer(rhport, tu_edpt_addr(0, TUSB_DIR_OUT), _dcd.setup_packet, sizeof(_dcd.setup_packet)); }