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