Hello Kind of Driver: Driver for a dongle usb-> serial Manufacturer: Io-Data Device: USB-RSA (based on EZUSB-CHip) Reference: My last post from 2016-04-02 19:49:40 GMT Description: The blocking behaviour that I reported in my last post seems to be induced by the set_bit and submit_urb in usbrsa_write. If I comment them, the "echo" or "stty" commands no longer block. If I only comment submit_urb, I experience blocking. For the complete source code, please refer to my posting from 2016-04-02 19:49:40 GMT ==== usbrsa_write ..... dev_dbg(&port->dev, "%s - port %d;URB allocated=%d", __func__, port->port_number, urb_index); /* reserve urb */ /* if I comment set_bit and submit_urb, I do not observe * blocking any longer */ set_bit(urb_index, &priv->write_urb_pool_lock); urb = priv->write_urb_pool[urb_index]; spin_unlock_irqrestore(&priv->lock, flags); /* copy data from userspace into urb transfer buffer */ bytes = (nof_bytes_to_be_sent > port->bulk_out_size) ? port->bulk_out_size : nof_bytes_to_be_sent; ... dev_dbg(&port->dev, "%s - port %d;bytes in urb=%d", __func__, port->port_number, bytes); usb_serial_debug_data(&port->dev, __func__, bytes, urb->transfer_buffer); urb->dev = serial->dev; urb->transfer_buffer_length = bytes; /* sent urb to USB-RSA */ //retval = usb_submit_urb(urb, GFP_ATOMIC); ...... Thanks Tilman -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
