On Tue, Jan 29, 2002 at 09:29:50AM +0100, Johan Brodin wrote: > > > > > > There should be two changes in bluetooth.c! > > > > > > 1. According to the Bluetooth specification each HCI packet must be > > > contained in one bulk_out_urb! > > > > > > Solution: Set bluetooth->bulk_out_buffer_size in > > usb_bluetooth_probe to > > > 1000! (line 1155) > > > > In looking at the Bluetooth spec (version 1.1) I don't see this > > requirement. Can you point me to where this is stated? > > Look at the middle section in page 786 of HCI USB transport layer.
Ah, you are correct. However, setting the buffer_size to 1000 (an arbitrary number) is also not correct. We can dynamically determine the max size over time, which is a better thing to do. > > > 2. The bulk_in_urb buffer must be larger then one HCI packet! > > > > > > Solution: Set bluetooth->bulk_in_buffer_size in > > usb_bluetooth_probe to 1000! > > > (line 1127) > > > > > > The maximum size of the HCI packet is determined during > > initialisation and > > > is soft and hardware dependent. There should however not be > > any HCI packet > > > bigger the 1000 byte! > > > > Again, why is this necessary? I don't see anything in the spec that > > states this. > > This is not stated in the specification! But when the bulk_in_buffer_size > not is increased I occasionally loose the first bytes of my inpacket to the > Bluetooth device driver. This error is not entirely removed when raising the > bulk_buffer_in_size but is now seems to occur only at maximum speed (570 > kbit/s). The error of loosing bytes under heavy load has previous been > reported to this list! But this problem has been reported to be fixed in the more recent versions of the kernel, correct? > > Are you using the Axis OpenBT stack, or some other stack? If another > > stack, can you point me to where I can get it from? > > I have used a commercial stack when testing the device driver. Ah, this is probably why no one else has seen these problems :) thanks, greg k-h _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
