linux/drivers/usb/serial/omninet.c
Joe Perches 7f26b3a753 drivers/usb: Remove unnecessary return's from void functions
Greg prefers this to go through the trivial tree.
http://lkml.org/lkml/2010/6/24/1

There are about 2500 void functions in drivers/usb
Only a few used return; at end of function.

Standardize them a bit.

Moved a statement down a line in drivers/usb/host/u132-hcd.c

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-08-10 14:25:42 +02:00

400 lines
10 KiB
C

/*
* USB ZyXEL omni.net LCD PLUS driver
*
* 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.
*
* See Documentation/usb/usb-serial.txt for more information on using this
* driver
*
* Please report both successes and troubles to the author at omninet@kroah.com
*
* (05/30/2001) gkh
* switched from using spinlock to a semaphore, which fixes lots of
* problems.
*
* (04/08/2001) gb
* Identify version on module load.
*
* (11/01/2000) Adam J. Richter
* usb_device_id table support
*
* (10/05/2000) gkh
* Fixed bug with urb->dev not being set properly, now that the usb
* core needs it.
*
* (08/28/2000) gkh
* Added locks for SMP safeness.
* Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
* than once.
* Fixed potential race in omninet_write_bulk_callback
*
* (07/19/2000) gkh
* Added module_init and module_exit functions to handle the fact that this
* driver is a loadable module now.
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
static int debug;
/*
* Version Information
*/
#define DRIVER_VERSION "v1.1"
#define DRIVER_AUTHOR "Alessandro Zummo"
#define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
#define ZYXEL_VENDOR_ID 0x0586
#define ZYXEL_OMNINET_ID 0x1000
/* This one seems to be a re-branded ZyXEL device */
#define BT_IGNITIONPRO_ID 0x2000
/* function prototypes */
static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
static void omninet_close(struct usb_serial_port *port);
static void omninet_read_bulk_callback(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 void omninet_disconnect(struct usb_serial *serial);
static void omninet_release(struct usb_serial *serial);
static int omninet_attach(struct usb_serial *serial);
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
{ USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, id_table);
static struct usb_driver omninet_driver = {
.name = "omninet",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table,
.no_dynamic_id = 1,
};
static struct usb_serial_driver zyxel_omninet_device = {
.driver = {
.owner = THIS_MODULE,
.name = "omninet",
},
.description = "ZyXEL - omni.net lcd plus usb",
.usb_driver = &omninet_driver,
.id_table = id_table,
.num_ports = 1,
.attach = omninet_attach,
.open = omninet_open,
.close = omninet_close,
.write = omninet_write,
.write_room = omninet_write_room,
.read_bulk_callback = omninet_read_bulk_callback,
.write_bulk_callback = omninet_write_bulk_callback,
.disconnect = omninet_disconnect,
.release = omninet_release,
};
/* The protocol.
*
* The omni.net always exchange 64 bytes of data with the host. The first
* four bytes are the control header, you can see it in the above structure.
*
* oh_seq is a sequence number. Don't know if/how it's used.
* oh_len is the length of the data bytes in the packet.
* oh_xxx Bit-mapped, related to handshaking and status info.
* I normally set it to 0x03 in trasmitted frames.
* 7: Active when the TA is in a CONNECTed state.
* 6: unknown
* 5: handshaking, unknown
* 4: handshaking, unknown
* 3: unknown, usually 0
* 2: unknown, usually 0
* 1: handshaking, unknown, usually set to 1 in trasmitted frames
* 0: handshaking, unknown, usually set to 1 in trasmitted frames
* oh_pad Probably a pad byte.
*
* After the header you will find data bytes if oh_len was greater than zero.
*
*/
struct omninet_header {
__u8 oh_seq;
__u8 oh_len;
__u8 oh_xxx;
__u8 oh_pad;
};
struct omninet_data {
__u8 od_outseq; /* Sequence number for bulk_out URBs */
};
static int omninet_attach(struct usb_serial *serial)
{
struct omninet_data *od;
struct usb_serial_port *port = serial->port[0];
od = kmalloc(sizeof(struct omninet_data), GFP_KERNEL);
if (!od) {
dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n",
__func__, sizeof(struct omninet_data));
return -ENOMEM;
}
usb_set_serial_port_data(port, od);
return 0;
}
static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port)
{
struct usb_serial *serial = port->serial;
struct usb_serial_port *wport;
int result = 0;
dbg("%s - port %d", __func__, port->number);
wport = serial->port[1];
tty_port_tty_set(&wport->port, tty);
/* Start reading from the device */
usb_fill_bulk_urb(port->read_urb, serial->dev,
usb_rcvbulkpipe(serial->dev,
port->bulk_in_endpointAddress),
port->read_urb->transfer_buffer,
port->read_urb->transfer_buffer_length,
omninet_read_bulk_callback, port);
result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result)
dev_err(&port->dev,
"%s - failed submitting read urb, error %d\n",
__func__, result);
return result;
}
static void omninet_close(struct usb_serial_port *port)
{
dbg("%s - port %d", __func__, port->number);
usb_kill_urb(port->read_urb);
}
#define OMNINET_DATAOFFSET 0x04
#define OMNINET_HEADERLEN sizeof(struct omninet_header)
#define OMNINET_BULKOUTSIZE (64 - OMNINET_HEADERLEN)
static void omninet_read_bulk_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
unsigned char *data = urb->transfer_buffer;
struct omninet_header *header = (struct omninet_header *) &data[0];
int status = urb->status;
int result;
int i;
dbg("%s - port %d", __func__, port->number);
if (status) {
dbg("%s - nonzero read bulk status received: %d",
__func__, status);
return;
}
if (debug && header->oh_xxx != 0x30) {
if (urb->actual_length) {
printk(KERN_DEBUG "%s: omninet_read %d: ",
__FILE__, header->oh_len);
for (i = 0; i < (header->oh_len +
OMNINET_HEADERLEN); i++)
printk("%.2x ", data[i]);
printk("\n");
}
}
if (urb->actual_length && header->oh_len) {
struct tty_struct *tty = tty_port_tty_get(&port->port);
tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
header->oh_len);
tty_flip_buffer_push(tty);
tty_kref_put(tty);
}
/* Continue trying to always read */
usb_fill_bulk_urb(urb, port->serial->dev,
usb_rcvbulkpipe(port->serial->dev,
port->bulk_in_endpointAddress),
urb->transfer_buffer, urb->transfer_buffer_length,
omninet_read_bulk_callback, port);
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result)
dev_err(&port->dev,
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
}
static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *buf, int count)
{
struct usb_serial *serial = port->serial;
struct usb_serial_port *wport = serial->port[1];
struct omninet_data *od = usb_get_serial_port_data(port);
struct omninet_header *header = (struct omninet_header *)
wport->write_urb->transfer_buffer;
int result;
dbg("%s - port %d", __func__, port->number);
if (count == 0) {
dbg("%s - write request of 0 bytes", __func__);
return 0;
}
spin_lock_bh(&wport->lock);
if (wport->write_urb_busy) {
spin_unlock_bh(&wport->lock);
dbg("%s - already writing", __func__);
return 0;
}
wport->write_urb_busy = 1;
spin_unlock_bh(&wport->lock);
count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
buf, count);
usb_serial_debug_data(debug, &port->dev, __func__, count,
wport->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 */
wport->write_urb->transfer_buffer_length = 64;
wport->write_urb->dev = serial->dev;
result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
if (result) {
wport->write_urb_busy = 0;
dev_err(&port->dev,
"%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;
struct usb_serial *serial = port->serial;
struct usb_serial_port *wport = serial->port[1];
int room = 0; /* Default: no room */
/* FIXME: no consistent locking for write_urb_busy */
if (wport->write_urb_busy)
room = wport->bulk_out_size - OMNINET_HEADERLEN;
dbg("%s - returns %d", __func__, room);
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;
dbg("%s - port %0x", __func__, port->number);
port->write_urb_busy = 0;
if (status) {
dbg("%s - nonzero write bulk status received: %d",
__func__, status);
return;
}
usb_serial_port_softint(port);
}
static void omninet_disconnect(struct usb_serial *serial)
{
struct usb_serial_port *wport = serial->port[1];
dbg("%s", __func__);
usb_kill_urb(wport->write_urb);
}
static void omninet_release(struct usb_serial *serial)
{
struct usb_serial_port *port = serial->port[0];
dbg("%s", __func__);
kfree(usb_get_serial_port_data(port));
}
static int __init omninet_init(void)
{
int retval;
retval = usb_serial_register(&zyxel_omninet_device);
if (retval)
goto failed_usb_serial_register;
retval = usb_register(&omninet_driver);
if (retval)
goto failed_usb_register;
printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
DRIVER_DESC "\n");
return 0;
failed_usb_register:
usb_serial_deregister(&zyxel_omninet_device);
failed_usb_serial_register:
return retval;
}
static void __exit omninet_exit(void)
{
usb_deregister(&omninet_driver);
usb_serial_deregister(&zyxel_omninet_device);
}
module_init(omninet_init);
module_exit(omninet_exit);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");