--- /dev/null
+/*
+ * AIRcable USB Bluetooth Dongle Driver.
+ *
+ * Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
+ * Copyright (C) 2006 Manuel Francisco Naranjo (naranjo.manuel@gmail.com)
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ *
+ * The device works as an standard CDC device, it has 2 interfaces, the first
+ * one is for firmware access and the second is the serial one.
+ * The protocol is very simply, there are two possibilities reading or writing.
+ * When writing the first urb must have a Header that starts with 0x20 0x29 the
+ * next two bytes must say how much data will be sent.
+ * When reading the process is almost equal except that the header starts with
+ * 0x00 0x20.
+ *
+ * The device simply need some stuff to understand data coming from the usb
+ * buffer: The First and Second byte is used for a Header, the Third and Fourth
+ * tells the device the amount of information the package holds.
+ * Packages are 60 bytes long Header Stuff.
+ * When writing to the device the first two bytes of the header are 0x20 0x29
+ * When reading the bytes are 0x00 0x20, or 0x00 0x10, there is an strange
+ * situation, when too much data arrives to the device because it sends the data
+ * but with out the header. I will use a simply hack to override this situation,
+ * if there is data coming that does not contain any header, then that is data
+ * that must go directly to the tty, as there is no documentation about if there
+ * is any other control code, I will simply check for the first
+ * one.
+ *
+ * The driver registers himself with the USB-serial core and the USB Core. I had
+ * to implement a probe function against USB-serial, because other way, the
+ * driver was attaching himself to both interfaces. I have tried with different
+ * configurations of usb_serial_driver with out exit, only the probe function
+ * could handle this correctly.
+ *
+ * I have taken some info from a Greg Kroah-Hartman article:
+ * http://www.linuxjournal.com/article/6573
+ * And from Linux Device Driver Kit CD, which is a great work, the authors taken
+ * the work to recompile lots of information an knowledge in drivers development
+ * and made it all available inside a cd.
+ * URL: http://kernel.org/pub/linux/kernel/people/gregkh/ddk/
+ *
+ */
+
+#include <asm/unaligned.h>
+#include <linux/tty.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/tty_flip.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+
+/* Vendor and Product ID */
+#define AIRCABLE_VID 0x16CA
+#define AIRCABLE_USB_PID 0x1502
+
+/* Protocol Stuff */
+#define HCI_HEADER_LENGTH 0x4
+#define TX_HEADER_0 0x20
+#define TX_HEADER_1 0x29
+#define RX_HEADER_0 0x00
+#define RX_HEADER_1 0x20
+#define HCI_COMPLETE_FRAME 64
+
+/* rx_flags */
+#define THROTTLED 0x01
+#define ACTUALLY_THROTTLED 0x02
+
+#define DRIVER_AUTHOR "Naranjo, Manuel Francisco <naranjo.manuel@gmail.com>, Johan Hovold <jhovold@gmail.com>"
+#define DRIVER_DESC "AIRcable USB Driver"
+
+/* ID table that will be registered with USB core */
+static const struct usb_device_id id_table[] = {
+ { USB_DEVICE(AIRCABLE_VID, AIRCABLE_USB_PID) },
+ { },
+};
+MODULE_DEVICE_TABLE(usb, id_table);
+
+static int aircable_prepare_write_buffer(struct usb_serial_port *port,
+ void *dest, size_t size)
+{
+ int count;
+ unsigned char *buf = dest;
+
+ count = kfifo_out_locked(&port->write_fifo, buf + HCI_HEADER_LENGTH,
+ size - HCI_HEADER_LENGTH, &port->lock);
+ buf[0] = TX_HEADER_0;
+ buf[1] = TX_HEADER_1;
+ put_unaligned_le16(count, &buf[2]);
+
+ return count + HCI_HEADER_LENGTH;
+}
+
+static int aircable_probe(struct usb_serial *serial,
+ const struct usb_device_id *id)
+{
+ struct usb_host_interface *iface_desc = serial->interface->
+ cur_altsetting;
+ struct usb_endpoint_descriptor *endpoint;
+ int num_bulk_out = 0;
+ int i;
+
+ for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
+ endpoint = &iface_desc->endpoint[i].desc;
+ if (usb_endpoint_is_bulk_out(endpoint)) {
+ dev_dbg(&serial->dev->dev,
+ "found bulk out on endpoint %d\n", i);
+ ++num_bulk_out;
+ }
+ }
+
+ if (num_bulk_out == 0) {
+ dev_dbg(&serial->dev->dev, "Invalid interface, discarding\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int aircable_process_packet(struct usb_serial_port *port,
+ int has_headers, char *packet, int len)
+{
+ if (has_headers) {
+ len -= HCI_HEADER_LENGTH;
+ packet += HCI_HEADER_LENGTH;
+ }
+ if (len <= 0) {
+ dev_dbg(&port->dev, "%s - malformed packet\n", __func__);
+ return 0;
+ }
+
+ tty_insert_flip_string(&port->port, packet, len);
+
+ return len;
+}
+
+static void aircable_process_read_urb(struct urb *urb)
+{
+ struct usb_serial_port *port = urb->context;
+ char *data = (char *)urb->transfer_buffer;
+ int has_headers;
+ int count;
+ int len;
+ int i;
+
+ has_headers = (urb->actual_length > 2 && data[0] == RX_HEADER_0);
+
+ count = 0;
+ for (i = 0; i < urb->actual_length; i += HCI_COMPLETE_FRAME) {
+ len = min_t(int, urb->actual_length - i, HCI_COMPLETE_FRAME);
+ count += aircable_process_packet(port, has_headers,
+ &data[i], len);
+ }
+
+ if (count)
+ tty_flip_buffer_push(&port->port);
+}
+
+static struct usb_serial_driver aircable_device = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "aircable",
+ },
+ .id_table = id_table,
+ .num_ports = 1,
+ .bulk_out_size = HCI_COMPLETE_FRAME,
+ .probe = aircable_probe,
+ .process_read_urb = aircable_process_read_urb,
+ .prepare_write_buffer = aircable_prepare_write_buffer,
+ .throttle = usb_serial_generic_throttle,
+ .unthrottle = usb_serial_generic_unthrottle,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+ &aircable_device, NULL
+};
+
+module_usb_serial_driver(serial_drivers, id_table);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff