omninet.c (4928B)
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 */ 34static void omninet_process_read_urb(struct urb *urb); 35static int omninet_prepare_write_buffer(struct usb_serial_port *port, 36 void *buf, size_t count); 37static int omninet_calc_num_ports(struct usb_serial *serial, 38 struct usb_serial_endpoints *epds); 39static int omninet_port_probe(struct usb_serial_port *port); 40static void omninet_port_remove(struct usb_serial_port *port); 41 42static 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}; 48MODULE_DEVICE_TABLE(usb, id_table); 49 50static struct usb_serial_driver zyxel_omninet_device = { 51 .driver = { 52 .owner = THIS_MODULE, 53 .name = "omninet", 54 }, 55 .description = "ZyXEL - omni.net usb", 56 .id_table = id_table, 57 .num_bulk_out = 2, 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, 63}; 64 65static struct usb_serial_driver * const serial_drivers[] = { 66 &zyxel_omninet_device, NULL 67}; 68 69 70/* 71 * The protocol. 72 * 73 * The omni.net always exchange 64 bytes of data with the host. The first 74 * four bytes are the control header. 75 * 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. 81 * 6: unknown 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. 89 * 90 * After the header you will find data bytes if oh_len was greater than zero. 91 */ 92struct omninet_header { 93 __u8 oh_seq; 94 __u8 oh_len; 95 __u8 oh_xxx; 96 __u8 oh_pad; 97}; 98 99struct omninet_data { 100 __u8 od_outseq; /* Sequence number for bulk_out URBs */ 101}; 102 103static int omninet_calc_num_ports(struct usb_serial *serial, 104 struct usb_serial_endpoints *epds) 105{ 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; 109 110 return 1; 111} 112 113static int omninet_port_probe(struct usb_serial_port *port) 114{ 115 struct omninet_data *od; 116 117 od = kzalloc(sizeof(*od), GFP_KERNEL); 118 if (!od) 119 return -ENOMEM; 120 121 usb_set_serial_port_data(port, od); 122 123 return 0; 124} 125 126static void omninet_port_remove(struct usb_serial_port *port) 127{ 128 struct omninet_data *od; 129 130 od = usb_get_serial_port_data(port); 131 kfree(od); 132} 133 134#define OMNINET_HEADERLEN 4 135#define OMNINET_BULKOUTSIZE 64 136#define OMNINET_PAYLOADSIZE (OMNINET_BULKOUTSIZE - OMNINET_HEADERLEN) 137 138static void omninet_process_read_urb(struct urb *urb) 139{ 140 struct usb_serial_port *port = urb->context; 141 const struct omninet_header *hdr = urb->transfer_buffer; 142 const unsigned char *data; 143 size_t data_len; 144 145 if (urb->actual_length <= OMNINET_HEADERLEN || !hdr->oh_len) 146 return; 147 148 data = (char *)urb->transfer_buffer + OMNINET_HEADERLEN; 149 data_len = min_t(size_t, urb->actual_length - OMNINET_HEADERLEN, 150 hdr->oh_len); 151 tty_insert_flip_string(&port->port, data, data_len); 152 tty_flip_buffer_push(&port->port); 153} 154 155static int omninet_prepare_write_buffer(struct usb_serial_port *port, 156 void *buf, size_t count) 157{ 158 struct omninet_data *od = usb_get_serial_port_data(port); 159 struct omninet_header *header = buf; 160 161 count = min_t(size_t, count, OMNINET_PAYLOADSIZE); 162 163 count = kfifo_out_locked(&port->write_fifo, buf + OMNINET_HEADERLEN, 164 count, &port->lock); 165 166 header->oh_seq = od->od_outseq++; 167 header->oh_len = count; 168 header->oh_xxx = 0x03; 169 header->oh_pad = 0x00; 170 171 /* always 64 bytes */ 172 return OMNINET_BULKOUTSIZE; 173} 174 175module_usb_serial_driver(serial_drivers, id_table); 176 177MODULE_AUTHOR(DRIVER_AUTHOR); 178MODULE_DESCRIPTION(DRIVER_DESC); 179MODULE_LICENSE("GPL v2");