USB: omninet: fix write_room
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / serial / omninet.c
blob6e976649fcae4c8554500802ccde05843fc9d0ed
1 /*
2 * USB ZyXEL omni.net LCD PLUS driver
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License version
6 * 2 as published by the Free Software Foundation.
8 * See Documentation/usb/usb-serial.txt for more information on using this
9 * driver
11 * Please report both successes and troubles to the author at omninet@kroah.com
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/tty.h>
19 #include <linux/tty_driver.h>
20 #include <linux/tty_flip.h>
21 #include <linux/module.h>
22 #include <linux/spinlock.h>
23 #include <linux/uaccess.h>
24 #include <linux/usb.h>
25 #include <linux/usb/serial.h>
27 static int debug;
30 * Version Information
32 #define DRIVER_VERSION "v1.1"
33 #define DRIVER_AUTHOR "Alessandro Zummo"
34 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
36 #define ZYXEL_VENDOR_ID 0x0586
37 #define ZYXEL_OMNINET_ID 0x1000
38 /* This one seems to be a re-branded ZyXEL device */
39 #define BT_IGNITIONPRO_ID 0x2000
41 /* function prototypes */
42 static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
43 static void omninet_close(struct usb_serial_port *port);
44 static void omninet_read_bulk_callback(struct urb *urb);
45 static void omninet_write_bulk_callback(struct urb *urb);
46 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
47 const unsigned char *buf, int count);
48 static int omninet_write_room(struct tty_struct *tty);
49 static void omninet_disconnect(struct usb_serial *serial);
50 static void omninet_release(struct usb_serial *serial);
51 static int omninet_attach(struct usb_serial *serial);
53 static const struct usb_device_id id_table[] = {
54 { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
55 { USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
56 { } /* Terminating entry */
59 MODULE_DEVICE_TABLE(usb, id_table);
61 static struct usb_driver omninet_driver = {
62 .name = "omninet",
63 .probe = usb_serial_probe,
64 .disconnect = usb_serial_disconnect,
65 .id_table = id_table,
66 .no_dynamic_id = 1,
70 static struct usb_serial_driver zyxel_omninet_device = {
71 .driver = {
72 .owner = THIS_MODULE,
73 .name = "omninet",
75 .description = "ZyXEL - omni.net lcd plus usb",
76 .usb_driver = &omninet_driver,
77 .id_table = id_table,
78 .num_ports = 1,
79 .attach = omninet_attach,
80 .open = omninet_open,
81 .close = omninet_close,
82 .write = omninet_write,
83 .write_room = omninet_write_room,
84 .read_bulk_callback = omninet_read_bulk_callback,
85 .write_bulk_callback = omninet_write_bulk_callback,
86 .disconnect = omninet_disconnect,
87 .release = omninet_release,
91 /* The protocol.
93 * The omni.net always exchange 64 bytes of data with the host. The first
94 * four bytes are the control header, you can see it in the above structure.
96 * oh_seq is a sequence number. Don't know if/how it's used.
97 * oh_len is the length of the data bytes in the packet.
98 * oh_xxx Bit-mapped, related to handshaking and status info.
99 * I normally set it to 0x03 in trasmitted frames.
100 * 7: Active when the TA is in a CONNECTed state.
101 * 6: unknown
102 * 5: handshaking, unknown
103 * 4: handshaking, unknown
104 * 3: unknown, usually 0
105 * 2: unknown, usually 0
106 * 1: handshaking, unknown, usually set to 1 in trasmitted frames
107 * 0: handshaking, unknown, usually set to 1 in trasmitted frames
108 * oh_pad Probably a pad byte.
110 * After the header you will find data bytes if oh_len was greater than zero.
114 struct omninet_header {
115 __u8 oh_seq;
116 __u8 oh_len;
117 __u8 oh_xxx;
118 __u8 oh_pad;
121 struct omninet_data {
122 __u8 od_outseq; /* Sequence number for bulk_out URBs */
125 static int omninet_attach(struct usb_serial *serial)
127 struct omninet_data *od;
128 struct usb_serial_port *port = serial->port[0];
130 od = kmalloc(sizeof(struct omninet_data), GFP_KERNEL);
131 if (!od) {
132 dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n",
133 __func__, sizeof(struct omninet_data));
134 return -ENOMEM;
136 usb_set_serial_port_data(port, od);
137 return 0;
140 static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port)
142 struct usb_serial *serial = port->serial;
143 struct usb_serial_port *wport;
144 int result = 0;
146 dbg("%s - port %d", __func__, port->number);
148 wport = serial->port[1];
149 tty_port_tty_set(&wport->port, tty);
151 /* Start reading from the device */
152 usb_fill_bulk_urb(port->read_urb, serial->dev,
153 usb_rcvbulkpipe(serial->dev,
154 port->bulk_in_endpointAddress),
155 port->read_urb->transfer_buffer,
156 port->read_urb->transfer_buffer_length,
157 omninet_read_bulk_callback, port);
158 result = usb_submit_urb(port->read_urb, GFP_KERNEL);
159 if (result)
160 dev_err(&port->dev,
161 "%s - failed submitting read urb, error %d\n",
162 __func__, result);
163 return result;
166 static void omninet_close(struct usb_serial_port *port)
168 dbg("%s - port %d", __func__, port->number);
169 usb_kill_urb(port->read_urb);
173 #define OMNINET_DATAOFFSET 0x04
174 #define OMNINET_HEADERLEN sizeof(struct omninet_header)
175 #define OMNINET_BULKOUTSIZE (64 - OMNINET_HEADERLEN)
177 static void omninet_read_bulk_callback(struct urb *urb)
179 struct usb_serial_port *port = urb->context;
180 unsigned char *data = urb->transfer_buffer;
181 struct omninet_header *header = (struct omninet_header *) &data[0];
182 int status = urb->status;
183 int result;
184 int i;
186 dbg("%s - port %d", __func__, port->number);
188 if (status) {
189 dbg("%s - nonzero read bulk status received: %d",
190 __func__, status);
191 return;
194 if (debug && header->oh_xxx != 0x30) {
195 if (urb->actual_length) {
196 printk(KERN_DEBUG "%s: omninet_read %d: ",
197 __FILE__, header->oh_len);
198 for (i = 0; i < (header->oh_len +
199 OMNINET_HEADERLEN); i++)
200 printk("%.2x ", data[i]);
201 printk("\n");
205 if (urb->actual_length && header->oh_len) {
206 struct tty_struct *tty = tty_port_tty_get(&port->port);
207 tty_insert_flip_string(tty, data + OMNINET_DATAOFFSET,
208 header->oh_len);
209 tty_flip_buffer_push(tty);
210 tty_kref_put(tty);
213 /* Continue trying to always read */
214 usb_fill_bulk_urb(urb, port->serial->dev,
215 usb_rcvbulkpipe(port->serial->dev,
216 port->bulk_in_endpointAddress),
217 urb->transfer_buffer, urb->transfer_buffer_length,
218 omninet_read_bulk_callback, port);
219 result = usb_submit_urb(urb, GFP_ATOMIC);
220 if (result)
221 dev_err(&port->dev,
222 "%s - failed resubmitting read urb, error %d\n",
223 __func__, result);
226 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
227 const unsigned char *buf, int count)
229 struct usb_serial *serial = port->serial;
230 struct usb_serial_port *wport = serial->port[1];
232 struct omninet_data *od = usb_get_serial_port_data(port);
233 struct omninet_header *header = (struct omninet_header *)
234 wport->write_urb->transfer_buffer;
236 int result;
238 dbg("%s - port %d", __func__, port->number);
240 if (count == 0) {
241 dbg("%s - write request of 0 bytes", __func__);
242 return 0;
245 spin_lock_bh(&wport->lock);
246 if (wport->write_urb_busy) {
247 spin_unlock_bh(&wport->lock);
248 dbg("%s - already writing", __func__);
249 return 0;
251 wport->write_urb_busy = 1;
252 spin_unlock_bh(&wport->lock);
254 count = (count > OMNINET_BULKOUTSIZE) ? OMNINET_BULKOUTSIZE : count;
256 memcpy(wport->write_urb->transfer_buffer + OMNINET_DATAOFFSET,
257 buf, count);
259 usb_serial_debug_data(debug, &port->dev, __func__, count,
260 wport->write_urb->transfer_buffer);
262 header->oh_seq = od->od_outseq++;
263 header->oh_len = count;
264 header->oh_xxx = 0x03;
265 header->oh_pad = 0x00;
267 /* send the data out the bulk port, always 64 bytes */
268 wport->write_urb->transfer_buffer_length = 64;
270 wport->write_urb->dev = serial->dev;
271 result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
272 if (result) {
273 wport->write_urb_busy = 0;
274 dev_err(&port->dev,
275 "%s - failed submitting write urb, error %d\n",
276 __func__, result);
277 } else
278 result = count;
280 return result;
284 static int omninet_write_room(struct tty_struct *tty)
286 struct usb_serial_port *port = tty->driver_data;
287 struct usb_serial *serial = port->serial;
288 struct usb_serial_port *wport = serial->port[1];
290 int room = 0; /* Default: no room */
292 /* FIXME: no consistent locking for write_urb_busy */
293 if (!wport->write_urb_busy)
294 room = wport->bulk_out_size - OMNINET_HEADERLEN;
296 dbg("%s - returns %d", __func__, room);
298 return room;
301 static void omninet_write_bulk_callback(struct urb *urb)
303 /* struct omninet_header *header = (struct omninet_header *)
304 urb->transfer_buffer; */
305 struct usb_serial_port *port = urb->context;
306 int status = urb->status;
308 dbg("%s - port %0x", __func__, port->number);
310 port->write_urb_busy = 0;
311 if (status) {
312 dbg("%s - nonzero write bulk status received: %d",
313 __func__, status);
314 return;
317 usb_serial_port_softint(port);
321 static void omninet_disconnect(struct usb_serial *serial)
323 struct usb_serial_port *wport = serial->port[1];
325 dbg("%s", __func__);
327 usb_kill_urb(wport->write_urb);
331 static void omninet_release(struct usb_serial *serial)
333 struct usb_serial_port *port = serial->port[0];
335 dbg("%s", __func__);
337 kfree(usb_get_serial_port_data(port));
341 static int __init omninet_init(void)
343 int retval;
344 retval = usb_serial_register(&zyxel_omninet_device);
345 if (retval)
346 goto failed_usb_serial_register;
347 retval = usb_register(&omninet_driver);
348 if (retval)
349 goto failed_usb_register;
350 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
351 DRIVER_DESC "\n");
352 return 0;
353 failed_usb_register:
354 usb_serial_deregister(&zyxel_omninet_device);
355 failed_usb_serial_register:
356 return retval;
360 static void __exit omninet_exit(void)
362 usb_deregister(&omninet_driver);
363 usb_serial_deregister(&zyxel_omninet_device);
367 module_init(omninet_init);
368 module_exit(omninet_exit);
370 MODULE_AUTHOR(DRIVER_AUTHOR);
371 MODULE_DESCRIPTION(DRIVER_DESC);
372 MODULE_LICENSE("GPL");
374 module_param(debug, bool, S_IRUGO | S_IWUSR);
375 MODULE_PARM_DESC(debug, "Debug enabled or not");