Merge tag 'pinctrl-v4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[sfrench/cifs-2.6.git] / drivers / usb / serial / omninet.c
1 /*
2  * USB ZyXEL omni.net LCD PLUS driver
3  *
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.
7  *
8  * See Documentation/usb/usb-serial.txt for more information on using this
9  * driver
10  *
11  * Please report both successes and troubles to the author at omninet@kroah.com
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/slab.h>
17 #include <linux/tty.h>
18 #include <linux/tty_driver.h>
19 #include <linux/tty_flip.h>
20 #include <linux/module.h>
21 #include <linux/uaccess.h>
22 #include <linux/usb.h>
23 #include <linux/usb/serial.h>
24
25 #define DRIVER_AUTHOR "Alessandro Zummo"
26 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
27
28 #define ZYXEL_VENDOR_ID         0x0586
29 #define ZYXEL_OMNINET_ID        0x1000
30 /* This one seems to be a re-branded ZyXEL device */
31 #define BT_IGNITIONPRO_ID       0x2000
32
33 /* function prototypes */
34 static int  omninet_open(struct tty_struct *tty, struct usb_serial_port *port);
35 static void omninet_process_read_urb(struct urb *urb);
36 static void omninet_write_bulk_callback(struct urb *urb);
37 static int  omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
38                                 const unsigned char *buf, int count);
39 static int  omninet_write_room(struct tty_struct *tty);
40 static void omninet_disconnect(struct usb_serial *serial);
41 static int omninet_attach(struct usb_serial *serial);
42 static int omninet_port_probe(struct usb_serial_port *port);
43 static int omninet_port_remove(struct usb_serial_port *port);
44
45 static const struct usb_device_id id_table[] = {
46         { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
47         { USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
48         { }                                             /* Terminating entry */
49 };
50 MODULE_DEVICE_TABLE(usb, id_table);
51
52 static struct usb_serial_driver zyxel_omninet_device = {
53         .driver = {
54                 .owner =        THIS_MODULE,
55                 .name =         "omninet",
56         },
57         .description =          "ZyXEL - omni.net lcd plus usb",
58         .id_table =             id_table,
59         .num_ports =            1,
60         .attach =               omninet_attach,
61         .port_probe =           omninet_port_probe,
62         .port_remove =          omninet_port_remove,
63         .open =                 omninet_open,
64         .write =                omninet_write,
65         .write_room =           omninet_write_room,
66         .write_bulk_callback =  omninet_write_bulk_callback,
67         .process_read_urb =     omninet_process_read_urb,
68         .disconnect =           omninet_disconnect,
69 };
70
71 static struct usb_serial_driver * const serial_drivers[] = {
72         &zyxel_omninet_device, NULL
73 };
74
75
76 /*
77  * The protocol.
78  *
79  * The omni.net always exchange 64 bytes of data with the host. The first
80  * four bytes are the control header.
81  *
82  * oh_seq is a sequence number. Don't know if/how it's used.
83  * oh_len is the length of the data bytes in the packet.
84  * oh_xxx Bit-mapped, related to handshaking and status info.
85  *      I normally set it to 0x03 in transmitted frames.
86  *      7: Active when the TA is in a CONNECTed state.
87  *      6: unknown
88  *      5: handshaking, unknown
89  *      4: handshaking, unknown
90  *      3: unknown, usually 0
91  *      2: unknown, usually 0
92  *      1: handshaking, unknown, usually set to 1 in transmitted frames
93  *      0: handshaking, unknown, usually set to 1 in transmitted frames
94  * oh_pad Probably a pad byte.
95  *
96  * After the header you will find data bytes if oh_len was greater than zero.
97  */
98 struct omninet_header {
99         __u8    oh_seq;
100         __u8    oh_len;
101         __u8    oh_xxx;
102         __u8    oh_pad;
103 };
104
105 struct omninet_data {
106         __u8    od_outseq;      /* Sequence number for bulk_out URBs */
107 };
108
109 static int omninet_attach(struct usb_serial *serial)
110 {
111         /* The second bulk-out endpoint is used for writing. */
112         if (serial->num_bulk_out < 2) {
113                 dev_err(&serial->interface->dev, "missing endpoints\n");
114                 return -ENODEV;
115         }
116
117         return 0;
118 }
119
120 static int omninet_port_probe(struct usb_serial_port *port)
121 {
122         struct omninet_data *od;
123
124         od = kzalloc(sizeof(*od), GFP_KERNEL);
125         if (!od)
126                 return -ENOMEM;
127
128         usb_set_serial_port_data(port, od);
129
130         return 0;
131 }
132
133 static int omninet_port_remove(struct usb_serial_port *port)
134 {
135         struct omninet_data *od;
136
137         od = usb_get_serial_port_data(port);
138         kfree(od);
139
140         return 0;
141 }
142
143 static int omninet_open(struct tty_struct *tty, struct usb_serial_port *port)
144 {
145         struct usb_serial       *serial = port->serial;
146         struct usb_serial_port  *wport;
147
148         wport = serial->port[1];
149         tty_port_tty_set(&wport->port, tty);
150
151         return usb_serial_generic_open(tty, port);
152 }
153
154 #define OMNINET_HEADERLEN       4
155 #define OMNINET_BULKOUTSIZE     64
156 #define OMNINET_PAYLOADSIZE     (OMNINET_BULKOUTSIZE - OMNINET_HEADERLEN)
157
158 static void omninet_process_read_urb(struct urb *urb)
159 {
160         struct usb_serial_port *port = urb->context;
161         const struct omninet_header *hdr = urb->transfer_buffer;
162         const unsigned char *data;
163         size_t data_len;
164
165         if (urb->actual_length <= OMNINET_HEADERLEN || !hdr->oh_len)
166                 return;
167
168         data = (char *)urb->transfer_buffer + OMNINET_HEADERLEN;
169         data_len = min_t(size_t, urb->actual_length - OMNINET_HEADERLEN,
170                                                                 hdr->oh_len);
171         tty_insert_flip_string(&port->port, data, data_len);
172         tty_flip_buffer_push(&port->port);
173 }
174
175 static int omninet_write(struct tty_struct *tty, struct usb_serial_port *port,
176                                         const unsigned char *buf, int count)
177 {
178         struct usb_serial *serial = port->serial;
179         struct usb_serial_port *wport = serial->port[1];
180
181         struct omninet_data *od = usb_get_serial_port_data(port);
182         struct omninet_header *header = (struct omninet_header *)
183                                         wport->write_urb->transfer_buffer;
184
185         int                     result;
186
187         if (count == 0) {
188                 dev_dbg(&port->dev, "%s - write request of 0 bytes\n", __func__);
189                 return 0;
190         }
191
192         if (!test_and_clear_bit(0, &port->write_urbs_free)) {
193                 dev_dbg(&port->dev, "%s - already writing\n", __func__);
194                 return 0;
195         }
196
197         count = (count > OMNINET_PAYLOADSIZE) ? OMNINET_PAYLOADSIZE : count;
198
199         memcpy(wport->write_urb->transfer_buffer + OMNINET_HEADERLEN,
200                                                                 buf, count);
201
202         usb_serial_debug_data(&port->dev, __func__, count,
203                               wport->write_urb->transfer_buffer);
204
205         header->oh_seq  = od->od_outseq++;
206         header->oh_len  = count;
207         header->oh_xxx  = 0x03;
208         header->oh_pad  = 0x00;
209
210         /* send the data out the bulk port, always 64 bytes */
211         wport->write_urb->transfer_buffer_length = OMNINET_BULKOUTSIZE;
212
213         result = usb_submit_urb(wport->write_urb, GFP_ATOMIC);
214         if (result) {
215                 set_bit(0, &wport->write_urbs_free);
216                 dev_err_console(port,
217                         "%s - failed submitting write urb, error %d\n",
218                         __func__, result);
219         } else
220                 result = count;
221
222         return result;
223 }
224
225
226 static int omninet_write_room(struct tty_struct *tty)
227 {
228         struct usb_serial_port *port = tty->driver_data;
229         struct usb_serial       *serial = port->serial;
230         struct usb_serial_port  *wport  = serial->port[1];
231
232         int room = 0; /* Default: no room */
233
234         if (test_bit(0, &wport->write_urbs_free))
235                 room = wport->bulk_out_size - OMNINET_HEADERLEN;
236
237         dev_dbg(&port->dev, "%s - returns %d\n", __func__, room);
238
239         return room;
240 }
241
242 static void omninet_write_bulk_callback(struct urb *urb)
243 {
244 /*      struct omninet_header   *header = (struct omninet_header  *)
245                                                 urb->transfer_buffer; */
246         struct usb_serial_port  *port   =  urb->context;
247         int status = urb->status;
248
249         set_bit(0, &port->write_urbs_free);
250         if (status) {
251                 dev_dbg(&port->dev, "%s - nonzero write bulk status received: %d\n",
252                         __func__, status);
253                 return;
254         }
255
256         usb_serial_port_softint(port);
257 }
258
259
260 static void omninet_disconnect(struct usb_serial *serial)
261 {
262         struct usb_serial_port *wport = serial->port[1];
263
264         usb_kill_urb(wport->write_urb);
265 }
266
267 module_usb_serial_driver(serial_drivers, id_table);
268
269 MODULE_AUTHOR(DRIVER_AUTHOR);
270 MODULE_DESCRIPTION(DRIVER_DESC);
271 MODULE_LICENSE("GPL");