diff options
Diffstat (limited to 'nuttx/arch/arm/src/stm32/stm32_otgfsdev.c')
| -rwxr-xr-x | nuttx/arch/arm/src/stm32/stm32_otgfsdev.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/nuttx/arch/arm/src/stm32/stm32_otgfsdev.c b/nuttx/arch/arm/src/stm32/stm32_otgfsdev.c index 2f297d09f..948ee4510 100755 --- a/nuttx/arch/arm/src/stm32/stm32_otgfsdev.c +++ b/nuttx/arch/arm/src/stm32/stm32_otgfsdev.c @@ -1027,6 +1027,11 @@ static void stm32_epin_request(FAR struct stm32_usbdev_s *priv, if (privreq->req.len == 0) { + /* The ZLP flag is set TRUE whenever we want to force the driver to + * send a zero-length-packet on the next pass through the loop (below). + * The flag is cleared whenever a packet is sent in the loop below. + */ + privep->zlp = true; } @@ -1043,6 +1048,10 @@ static void stm32_epin_request(FAR struct stm32_usbdev_s *priv, bytesleft = privreq->req.len - privreq->req.xfrd; nbytes = bytesleft; + /* Assume no zero-length-packet on the next pass through this loop */ + + privep->zlp = false; + /* Limit the size of the transfer to one full packet and handle * zero-length packets (ZLPs). */ @@ -1053,7 +1062,6 @@ static void stm32_epin_request(FAR struct stm32_usbdev_s *priv, * the request. */ - privep->zlp = false; if (nbytes >= privep->ep.maxpacket) { nbytes = privep->ep.maxpacket; @@ -1066,6 +1074,14 @@ static void stm32_epin_request(FAR struct stm32_usbdev_s *priv, if (bytesleft == privep->ep.maxpacket && (privreq->req.flags & USBDEV_REQFLAGS_NULLPKT) != 0) { + /* The ZLP flag is set TRUE whenever we want to force + * the driver to send a zero-length-packet on the next + * pass through this loop. The flag is cleared (above) + * whenever we are committed to sending any packet and + * set here when we want to force one more pass through + * the loop. + */ + privep->zlp = true; } } |