USB: cdc-acm: work around some broken devices
This patch introduces a work around for cdc-acm devices which are
low speed contrary to the specification, which requires bulk endpoints
which are banned in low speed and converted by usbcore to virtual
interrupt endpoints if they are used nevertheless.
Signed-off-by: Arseniy Lartsev <ars3n@yandex.ru>
Cc: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 3f10459..5b15d9d 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -387,6 +387,7 @@
struct acm_ru *rcv;
unsigned long flags;
unsigned char throttled;
+ struct usb_host_endpoint *ep;
dbg("Entering acm_rx_tasklet");
@@ -462,11 +463,20 @@
rcv->buffer = buf;
- usb_fill_bulk_urb(rcv->urb, acm->dev,
- acm->rx_endpoint,
- buf->base,
- acm->readsize,
- acm_read_bulk, rcv);
+ ep = (usb_pipein(acm->rx_endpoint) ? acm->dev->ep_in : acm->dev->ep_out)
+ [usb_pipeendpoint(acm->rx_endpoint)];
+ if (usb_endpoint_xfer_int(&ep->desc))
+ usb_fill_int_urb(rcv->urb, acm->dev,
+ acm->rx_endpoint,
+ buf->base,
+ acm->readsize,
+ acm_read_bulk, rcv, ep->desc.bInterval);
+ else
+ usb_fill_bulk_urb(rcv->urb, acm->dev,
+ acm->rx_endpoint,
+ buf->base,
+ acm->readsize,
+ acm_read_bulk, rcv);
rcv->urb->transfer_dma = buf->dma;
rcv->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
@@ -1227,9 +1237,14 @@
goto alloc_fail7;
}
- usb_fill_bulk_urb(snd->urb, usb_dev,
- usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
- NULL, acm->writesize, acm_write_bulk, snd);
+ if (usb_endpoint_xfer_int(epwrite))
+ usb_fill_int_urb(snd->urb, usb_dev,
+ usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
+ NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
+ else
+ usb_fill_bulk_urb(snd->urb, usb_dev,
+ usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
+ NULL, acm->writesize, acm_write_bulk, snd);
snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
snd->instance = acm;
}