Fix array size issue when using the pre-scaling feature for

ISOCHRONOUS USB transfers. Make sure enough length and buffer pointers
are allocated when setting up the libusb transfer structure to support
the maximum number of frames the kernel can handle.

MFC after:	1 week
This commit is contained in:
Hans Petter Selasky 2016-09-02 08:44:14 +00:00
parent 7a83ecc454
commit 5f51814803

View File

@ -176,6 +176,12 @@ libusb20_tr_open_stream(struct libusb20_transfer *xfer, uint32_t MaxBufSize,
return (LIBUSB20_ERROR_BUSY);
if (MaxFrameCount & LIBUSB20_MAX_FRAME_PRE_SCALE) {
MaxFrameCount &= ~LIBUSB20_MAX_FRAME_PRE_SCALE;
/*
* The kernel can setup 8 times more frames when
* pre-scaling ISOCHRONOUS transfers. Make sure the
* length and pointer buffers are big enough:
*/
MaxFrameCount *= 8;
pre_scale = 1;
} else {
pre_scale = 0;
@ -200,8 +206,13 @@ libusb20_tr_open_stream(struct libusb20_transfer *xfer, uint32_t MaxBufSize,
}
memset(xfer->ppBuffer, 0, size);
error = xfer->pdev->methods->tr_open(xfer, MaxBufSize,
MaxFrameCount, ep_no, stream_id, pre_scale);
if (pre_scale) {
error = xfer->pdev->methods->tr_open(xfer, MaxBufSize,
MaxFrameCount / 8, ep_no, stream_id, 1);
} else {
error = xfer->pdev->methods->tr_open(xfer, MaxBufSize,
MaxFrameCount, ep_no, stream_id, 0);
}
if (error) {
free(xfer->ppBuffer);