diff options
Diffstat (limited to 'drivers/input/touchscreen/usbtouchscreen.c')
-rw-r--r-- | drivers/input/touchscreen/usbtouchscreen.c | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c index ae4b6b90362..5f87bed0546 100644 --- a/drivers/input/touchscreen/usbtouchscreen.c +++ b/drivers/input/touchscreen/usbtouchscreen.c @@ -106,6 +106,7 @@ struct usbtouch_device_info { struct usbtouch_usb { unsigned char *data; dma_addr_t data_dma; + int data_size; unsigned char *buffer; int buf_len; struct urb *irq; @@ -1521,7 +1522,7 @@ static int usbtouch_reset_resume(struct usb_interface *intf) static void usbtouch_free_buffers(struct usb_device *udev, struct usbtouch_usb *usbtouch) { - usb_free_coherent(udev, usbtouch->type->rept_size, + usb_free_coherent(udev, usbtouch->data_size, usbtouch->data, usbtouch->data_dma); kfree(usbtouch->buffer); } @@ -1566,7 +1567,20 @@ static int usbtouch_probe(struct usb_interface *intf, if (!type->process_pkt) type->process_pkt = usbtouch_process_pkt; - usbtouch->data = usb_alloc_coherent(udev, type->rept_size, + usbtouch->data_size = type->rept_size; + if (type->get_pkt_len) { + /* + * When dealing with variable-length packets we should + * not request more than wMaxPacketSize bytes at once + * as we do not know if there is more data coming or + * we filled exactly wMaxPacketSize bytes and there is + * nothing else. + */ + usbtouch->data_size = min(usbtouch->data_size, + usb_endpoint_maxp(endpoint)); + } + + usbtouch->data = usb_alloc_coherent(udev, usbtouch->data_size, GFP_KERNEL, &usbtouch->data_dma); if (!usbtouch->data) goto out_free; @@ -1626,12 +1640,12 @@ static int usbtouch_probe(struct usb_interface *intf, if (usb_endpoint_type(endpoint) == USB_ENDPOINT_XFER_INT) usb_fill_int_urb(usbtouch->irq, udev, usb_rcvintpipe(udev, endpoint->bEndpointAddress), - usbtouch->data, type->rept_size, + usbtouch->data, usbtouch->data_size, usbtouch_irq, usbtouch, endpoint->bInterval); else usb_fill_bulk_urb(usbtouch->irq, udev, usb_rcvbulkpipe(udev, endpoint->bEndpointAddress), - usbtouch->data, type->rept_size, + usbtouch->data, usbtouch->data_size, usbtouch_irq, usbtouch); usbtouch->irq->dev = udev; |