1 // SPDX-License-Identifier: GPL-2.0
3 * USB ZyXEL omni.net LCD PLUS driver
5 * Copyright (C) 2013,2017 Johan Hovold <johan@kernel.org>
7 * See Documentation/usb/usb-serial.rst for more information on using this
10 * Please report both successes and troubles to the author at omninet@kroah.com
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/tty.h>
17 #include <linux/tty_driver.h>
18 #include <linux/tty_flip.h>
19 #include <linux/module.h>
20 #include <linux/uaccess.h>
21 #include <linux/usb.h>
22 #include <linux/usb/serial.h>
24 #define DRIVER_AUTHOR "Alessandro Zummo"
25 #define DRIVER_DESC "USB ZyXEL omni.net LCD PLUS Driver"
27 #define ZYXEL_VENDOR_ID 0x0586
28 #define ZYXEL_OMNINET_ID 0x1000
29 #define ZYXEL_OMNI_56K_PLUS_ID 0x1500
30 /* This one seems to be a re-branded ZyXEL device */
31 #define BT_IGNITIONPRO_ID 0x2000
33 /* function prototypes */
34 static void omninet_process_read_urb(struct urb *urb);
35 static int omninet_prepare_write_buffer(struct usb_serial_port *port,
36 void *buf, size_t count);
37 static int omninet_calc_num_ports(struct usb_serial *serial,
38 struct usb_serial_endpoints *epds);
39 static int omninet_port_probe(struct usb_serial_port *port);
40 static int omninet_port_remove(struct usb_serial_port *port);
42 static const struct usb_device_id id_table[] = {
43 { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNINET_ID) },
44 { USB_DEVICE(ZYXEL_VENDOR_ID, ZYXEL_OMNI_56K_PLUS_ID) },
45 { USB_DEVICE(ZYXEL_VENDOR_ID, BT_IGNITIONPRO_ID) },
46 { } /* Terminating entry */
48 MODULE_DEVICE_TABLE(usb, id_table);
50 static struct usb_serial_driver zyxel_omninet_device = {
55 .description = "ZyXEL - omni.net lcd plus usb",
58 .calc_num_ports = omninet_calc_num_ports,
59 .port_probe = omninet_port_probe,
60 .port_remove = omninet_port_remove,
61 .process_read_urb = omninet_process_read_urb,
62 .prepare_write_buffer = omninet_prepare_write_buffer,
65 static struct usb_serial_driver * const serial_drivers[] = {
66 &zyxel_omninet_device, NULL
73 * The omni.net always exchange 64 bytes of data with the host. The first
74 * four bytes are the control header.
76 * oh_seq is a sequence number. Don't know if/how it's used.
77 * oh_len is the length of the data bytes in the packet.
78 * oh_xxx Bit-mapped, related to handshaking and status info.
79 * I normally set it to 0x03 in transmitted frames.
80 * 7: Active when the TA is in a CONNECTed state.
82 * 5: handshaking, unknown
83 * 4: handshaking, unknown
84 * 3: unknown, usually 0
85 * 2: unknown, usually 0
86 * 1: handshaking, unknown, usually set to 1 in transmitted frames
87 * 0: handshaking, unknown, usually set to 1 in transmitted frames
88 * oh_pad Probably a pad byte.
90 * After the header you will find data bytes if oh_len was greater than zero.
92 struct omninet_header {
100 __u8 od_outseq; /* Sequence number for bulk_out URBs */
103 static int omninet_calc_num_ports(struct usb_serial *serial,
104 struct usb_serial_endpoints *epds)
106 /* We need only the second bulk-out for our single-port device. */
107 epds->bulk_out[0] = epds->bulk_out[1];
108 epds->num_bulk_out = 1;
113 static int omninet_port_probe(struct usb_serial_port *port)
115 struct omninet_data *od;
117 od = kzalloc(sizeof(*od), GFP_KERNEL);
121 usb_set_serial_port_data(port, od);
126 static int omninet_port_remove(struct usb_serial_port *port)
128 struct omninet_data *od;
130 od = usb_get_serial_port_data(port);
136 #define OMNINET_HEADERLEN 4
137 #define OMNINET_BULKOUTSIZE 64
138 #define OMNINET_PAYLOADSIZE (OMNINET_BULKOUTSIZE - OMNINET_HEADERLEN)
140 static void omninet_process_read_urb(struct urb *urb)
142 struct usb_serial_port *port = urb->context;
143 const struct omninet_header *hdr = urb->transfer_buffer;
144 const unsigned char *data;
147 if (urb->actual_length <= OMNINET_HEADERLEN || !hdr->oh_len)
150 data = (char *)urb->transfer_buffer + OMNINET_HEADERLEN;
151 data_len = min_t(size_t, urb->actual_length - OMNINET_HEADERLEN,
153 tty_insert_flip_string(&port->port, data, data_len);
154 tty_flip_buffer_push(&port->port);
157 static int omninet_prepare_write_buffer(struct usb_serial_port *port,
158 void *buf, size_t count)
160 struct omninet_data *od = usb_get_serial_port_data(port);
161 struct omninet_header *header = buf;
163 count = min_t(size_t, count, OMNINET_PAYLOADSIZE);
165 count = kfifo_out_locked(&port->write_fifo, buf + OMNINET_HEADERLEN,
168 header->oh_seq = od->od_outseq++;
169 header->oh_len = count;
170 header->oh_xxx = 0x03;
171 header->oh_pad = 0x00;
173 /* always 64 bytes */
174 return OMNINET_BULKOUTSIZE;
177 module_usb_serial_driver(serial_drivers, id_table);
179 MODULE_AUTHOR(DRIVER_AUTHOR);
180 MODULE_DESCRIPTION(DRIVER_DESC);
181 MODULE_LICENSE("GPL v2");