USB: serial: omninet: use generic write implementation

Now that the endpoint-port mapping has been properly set up during
probe, we can switch to using the more efficient generic write
implementation.

Note that this currently means that chars_in_buffer now overcounts
slightly as we always write a full endpoint-sized packet.

Also add a copyright entry.

Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/omninet.c b/drivers/usb/serial/omninet.c
index 558a620d886821be41ffbdd9d6d1a09ad63728b6..efcd7feed6f4d1c882627736de30253ca2858da6 100644 (file)
--- a/drivers/usb/serial/omninet.c
+++ b/drivers/usb/serial/omninet.c
@@ -1,6 +1,8 @@
 /*
  * USB ZyXEL omni.net LCD PLUS driver
  *
+ * Copyright (C) 2013,2017 Johan Hovold <johan@kernel.org>
+ *
  *     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.
@@ -32,10 +34,8 @@
 
 /* function prototypes */
 static void omninet_process_read_urb(struct urb *urb);
-static void omninet_write_bulk_callback(struct urb *urb);
-static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
-                               const unsigned char *buf, int count);
-static int  omninet_write_room(struct tty_struct *tty);
+static int omninet_prepare_write_buffer(struct usb_serial_port *port,
+                               void *buf, size_t count);
 static int omninet_calc_num_ports(struct usb_serial *serial,
                                struct usb_serial_endpoints *epds);
 static int omninet_port_probe(struct usb_serial_port *port);
@@ -59,10 +59,8 @@ static struct usb_serial_driver zyxel_omninet_device = {
        .calc_num_ports =       omninet_calc_num_ports,
        .port_probe =           omninet_port_probe,
        .port_remove =          omninet_port_remove,
-       .write =                omninet_write,
-       .write_room =           omninet_write_room,
-       .write_bulk_callback =  omninet_write_bulk_callback,
        .process_read_urb =     omninet_process_read_urb,
+       .prepare_write_buffer = omninet_prepare_write_buffer,
 };
 
 static struct usb_serial_driver * const serial_drivers[] = {
@@ -157,81 +155,24 @@ static void omninet_process_read_urb(struct urb *urb)
        tty_flip_buffer_push(&port->port);
 }
 
-static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
-                                       const unsigned char *buf, int count)
+static int omninet_prepare_write_buffer(struct usb_serial_port *port,
+                                       void *buf, size_t count)
 {
        struct omninet_data *od = usb_get_serial_port_data(port);
-       struct omninet_header *header = (struct omninet_header *)
-                                       port->write_urb->transfer_buffer;
-       int                     result;
-
-       if (count == 0) {
-               dev_dbg(&port->dev, "%s - write request of 0 bytes\n", __func__);
-               return 0;
-       }
-
-       if (!test_and_clear_bit(0, &port->write_urbs_free)) {
-               dev_dbg(&port->dev, "%s - already writing\n", __func__);
-               return 0;
-       }
-
-       count = (count > OMNINET_PAYLOADSIZE) ? OMNINET_PAYLOADSIZE : count;
-
-       memcpy(port->write_urb->transfer_buffer + OMNINET_HEADERLEN,
-                                                               buf, count);
-
-       usb_serial_debug_data(&port->dev, __func__, count,
-                             port->write_urb->transfer_buffer);
-
-       header->oh_seq  = od->od_outseq++;
-       header->oh_len  = count;
-       header->oh_xxx  = 0x03;
-       header->oh_pad  = 0x00;
-
-       /* send the data out the bulk port, always 64 bytes */
-       port->write_urb->transfer_buffer_length = OMNINET_BULKOUTSIZE;
-
-       result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
-       if (result) {
-               set_bit(0, &port->write_urbs_free);
-               dev_err_console(port,
-                       "%s - failed submitting write urb, error %d\n",
-                       __func__, result);
-       } else
-               result = count;
-
-       return result;
-}
-
-
-static int omninet_write_room(struct tty_struct *tty)
-{
-       struct usb_serial_port *port = tty->driver_data;
-       int room = 0; /* Default: no room */
+       struct omninet_header *header = buf;
 
-       if (test_bit(0, &port->write_urbs_free))
-               room = port->bulk_out_size - OMNINET_HEADERLEN;
+       count = min_t(size_t, count, OMNINET_PAYLOADSIZE);
 
-       dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
+       count = kfifo_out_locked(&port->write_fifo, buf + OMNINET_HEADERLEN,
+                       count, &port->lock);
 
-       return room;
-}
-
-static void omninet_write_bulk_callback(struct urb *urb)
-{
-/*     struct omninet_header   *header = (struct omninet_header  *)
-                                               urb->transfer_buffer; */
-       struct usb_serial_port  *port   =  urb->context;
-       int status = urb->status;
-
-       set_bit(0, &port->write_urbs_free);
-       if (status) {
-               dev_dbg(&port->dev, "%s - nonzero write bulk status received: %d\n",
-                       __func__, status);
-               return;
-       }
+       header->oh_seq = od->od_outseq++;
+       header->oh_len = count;
+       header->oh_xxx = 0x03;
+       header->oh_pad = 0x00;
 
-       usb_serial_port_softint(port);
+       /* always 64 bytes */
+       return OMNINET_BULKOUTSIZE;
 }
 
 module_usb_serial_driver(serial_drivers, id_table);