1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * USB ZyXEL omni.net driver 4 * 5 * Copyright (C) 2013,2017 Johan Hovold <johan@kernel.org> 6 * 7 * See Documentation/usb/usb-serial.rst for more information on using this 8 * driver 9 * 10 * Please report both successes and troubles to the author at omninet@kroah.com 11 */ 12 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> 23 24 #define DRIVER_AUTHOR "Alessandro Zummo" 25 #define DRIVER_DESC "USB ZyXEL omni.net Driver" 26 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 32 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 void omninet_port_remove(struct usb_serial_port *port); 41 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 */ 47 }; 48 MODULE_DEVICE_TABLE(usb, id_table); 49 50 static struct usb_serial_driver zyxel_omninet_device = { 51 .driver = { 52 .name = "omninet", 53 }, 54 .description = "ZyXEL - omni.net usb", 55 .id_table = id_table, 56 .num_bulk_out = 2, 57 .calc_num_ports = omninet_calc_num_ports, 58 .port_probe = omninet_port_probe, 59 .port_remove = omninet_port_remove, 60 .process_read_urb = omninet_process_read_urb, 61 .prepare_write_buffer = omninet_prepare_write_buffer, 62 }; 63 64 static struct usb_serial_driver * const serial_drivers[] = { 65 &zyxel_omninet_device, NULL 66 }; 67 68 69 /* 70 * The protocol. 71 * 72 * The omni.net always exchange 64 bytes of data with the host. The first 73 * four bytes are the control header. 74 * 75 * oh_seq is a sequence number. Don't know if/how it's used. 76 * oh_len is the length of the data bytes in the packet. 77 * oh_xxx Bit-mapped, related to handshaking and status info. 78 * I normally set it to 0x03 in transmitted frames. 79 * 7: Active when the TA is in a CONNECTed state. 80 * 6: unknown 81 * 5: handshaking, unknown 82 * 4: handshaking, unknown 83 * 3: unknown, usually 0 84 * 2: unknown, usually 0 85 * 1: handshaking, unknown, usually set to 1 in transmitted frames 86 * 0: handshaking, unknown, usually set to 1 in transmitted frames 87 * oh_pad Probably a pad byte. 88 * 89 * After the header you will find data bytes if oh_len was greater than zero. 90 */ 91 struct omninet_header { 92 __u8 oh_seq; 93 __u8 oh_len; 94 __u8 oh_xxx; 95 __u8 oh_pad; 96 }; 97 98 struct omninet_data { 99 __u8 od_outseq; /* Sequence number for bulk_out URBs */ 100 }; 101 102 static int omninet_calc_num_ports(struct usb_serial *serial, 103 struct usb_serial_endpoints *epds) 104 { 105 /* We need only the second bulk-out for our single-port device. */ 106 epds->bulk_out[0] = epds->bulk_out[1]; 107 epds->num_bulk_out = 1; 108 109 return 1; 110 } 111 112 static int omninet_port_probe(struct usb_serial_port *port) 113 { 114 struct omninet_data *od; 115 116 od = kzalloc(sizeof(*od), GFP_KERNEL); 117 if (!od) 118 return -ENOMEM; 119 120 usb_set_serial_port_data(port, od); 121 122 return 0; 123 } 124 125 static void omninet_port_remove(struct usb_serial_port *port) 126 { 127 struct omninet_data *od; 128 129 od = usb_get_serial_port_data(port); 130 kfree(od); 131 } 132 133 #define OMNINET_HEADERLEN 4 134 #define OMNINET_BULKOUTSIZE 64 135 #define OMNINET_PAYLOADSIZE (OMNINET_BULKOUTSIZE - OMNINET_HEADERLEN) 136 137 static void omninet_process_read_urb(struct urb *urb) 138 { 139 struct usb_serial_port *port = urb->context; 140 const struct omninet_header *hdr = urb->transfer_buffer; 141 const unsigned char *data; 142 size_t data_len; 143 144 if (urb->actual_length <= OMNINET_HEADERLEN || !hdr->oh_len) 145 return; 146 147 data = (char *)urb->transfer_buffer + OMNINET_HEADERLEN; 148 data_len = min_t(size_t, urb->actual_length - OMNINET_HEADERLEN, 149 hdr->oh_len); 150 tty_insert_flip_string(&port->port, data, data_len); 151 tty_flip_buffer_push(&port->port); 152 } 153 154 static int omninet_prepare_write_buffer(struct usb_serial_port *port, 155 void *buf, size_t count) 156 { 157 struct omninet_data *od = usb_get_serial_port_data(port); 158 struct omninet_header *header = buf; 159 160 count = min_t(size_t, count, OMNINET_PAYLOADSIZE); 161 162 count = kfifo_out_locked(&port->write_fifo, buf + OMNINET_HEADERLEN, 163 count, &port->lock); 164 165 header->oh_seq = od->od_outseq++; 166 header->oh_len = count; 167 header->oh_xxx = 0x03; 168 header->oh_pad = 0x00; 169 170 /* always 64 bytes */ 171 return OMNINET_BULKOUTSIZE; 172 } 173 174 module_usb_serial_driver(serial_drivers, id_table); 175 176 MODULE_AUTHOR(DRIVER_AUTHOR); 177 MODULE_DESCRIPTION(DRIVER_DESC); 178 MODULE_LICENSE("GPL v2"); 179