diff options
-rw-r--r-- | sys/dev/usb/uvisor.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/sys/dev/usb/uvisor.c b/sys/dev/usb/uvisor.c index e22cf3a..72b64a4 100644 --- a/sys/dev/usb/uvisor.c +++ b/sys/dev/usb/uvisor.c @@ -144,7 +144,17 @@ struct uvisor_connection_info { #define UVISOR_GET_PALM_INFORMATION_LEN 0x14 -#define UVISORIBUFSIZE 1024 +/* + * Crank down UVISORBUFSIZE from 1024 to 64 to avoid a problem where + * the Palm device and the USB host controller deadlock. The USB host + * controller is expecting an early-end-of-transmission packet with 0 + * data, and the Palm doesn't send one because it's already + * communicated the amount of data it's going to send in a header + * (which ucom/uvisor are oblivious to). This is the problem that has + * been known on the pilot-link lists as the "[Free]BSD USB problem", + * but not understood. + */ +#define UVISORIBUFSIZE 64 #define UVISOROBUFSIZE 1024 struct uvisor_softc { |