1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * ncm.c -- NCM gadget driver 4 * 5 * Copyright (C) 2010 Nokia Corporation 6 * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com> 7 * 8 * The driver borrows from ether.c which is: 9 * 10 * Copyright (C) 2003-2005,2008 David Brownell 11 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger 12 * Copyright (C) 2008 Nokia Corporation 13 */ 14 15 /* #define DEBUG */ 16 /* #define VERBOSE_DEBUG */ 17 18 #include <linux/kernel.h> 19 #include <linux/module.h> 20 #include <linux/usb/composite.h> 21 22 #include "u_ether.h" 23 #include "u_ncm.h" 24 25 #define DRIVER_DESC "NCM Gadget" 26 27 /*-------------------------------------------------------------------------*/ 28 29 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!! 30 * Instead: allocate your own, using normal USB-IF procedures. 31 */ 32 33 /* Thanks to NetChip Technologies for donating this product ID. 34 * It's for devices with only CDC Ethernet configurations. 35 */ 36 #define CDC_VENDOR_NUM 0x0525 /* NetChip */ 37 #define CDC_PRODUCT_NUM 0xa4a1 /* Linux-USB Ethernet Gadget */ 38 39 /*-------------------------------------------------------------------------*/ 40 USB_GADGET_COMPOSITE_OPTIONS(); 41 42 USB_ETHERNET_MODULE_PARAMETERS(); 43 44 static struct usb_device_descriptor device_desc = { 45 .bLength = sizeof device_desc, 46 .bDescriptorType = USB_DT_DEVICE, 47 48 /* .bcdUSB = DYNAMIC */ 49 50 .bDeviceClass = USB_CLASS_COMM, 51 .bDeviceSubClass = 0, 52 .bDeviceProtocol = 0, 53 /* .bMaxPacketSize0 = f(hardware) */ 54 55 /* Vendor and product id defaults change according to what configs 56 * we support. (As does bNumConfigurations.) These values can 57 * also be overridden by module parameters. 58 */ 59 .idVendor = cpu_to_le16 (CDC_VENDOR_NUM), 60 .idProduct = cpu_to_le16 (CDC_PRODUCT_NUM), 61 /* .bcdDevice = f(hardware) */ 62 /* .iManufacturer = DYNAMIC */ 63 /* .iProduct = DYNAMIC */ 64 /* NO SERIAL NUMBER */ 65 .bNumConfigurations = 1, 66 }; 67 68 static const struct usb_descriptor_header *otg_desc[2]; 69 70 /* string IDs are assigned dynamically */ 71 static struct usb_string strings_dev[] = { 72 [USB_GADGET_MANUFACTURER_IDX].s = "", 73 [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC, 74 [USB_GADGET_SERIAL_IDX].s = "", 75 { } /* end of list */ 76 }; 77 78 static struct usb_gadget_strings stringtab_dev = { 79 .language = 0x0409, /* en-us */ 80 .strings = strings_dev, 81 }; 82 83 static struct usb_gadget_strings *dev_strings[] = { 84 &stringtab_dev, 85 NULL, 86 }; 87 88 static struct usb_function_instance *f_ncm_inst; 89 static struct usb_function *f_ncm; 90 91 /*-------------------------------------------------------------------------*/ 92 93 static int ncm_do_config(struct usb_configuration *c) 94 { 95 int status; 96 97 /* FIXME alloc iConfiguration string, set it in c->strings */ 98 99 if (gadget_is_otg(c->cdev->gadget)) { 100 c->descriptors = otg_desc; 101 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP; 102 } 103 104 f_ncm = usb_get_function(f_ncm_inst); 105 if (IS_ERR(f_ncm)) { 106 status = PTR_ERR(f_ncm); 107 return status; 108 } 109 110 status = usb_add_function(c, f_ncm); 111 if (status < 0) { 112 usb_put_function(f_ncm); 113 return status; 114 } 115 116 return 0; 117 } 118 119 static struct usb_configuration ncm_config_driver = { 120 /* .label = f(hardware) */ 121 .label = "CDC Ethernet (NCM)", 122 .bConfigurationValue = 1, 123 /* .iConfiguration = DYNAMIC */ 124 .bmAttributes = USB_CONFIG_ATT_SELFPOWER, 125 }; 126 127 /*-------------------------------------------------------------------------*/ 128 129 static int gncm_bind(struct usb_composite_dev *cdev) 130 { 131 struct usb_gadget *gadget = cdev->gadget; 132 struct f_ncm_opts *ncm_opts; 133 int status; 134 135 f_ncm_inst = usb_get_function_instance("ncm"); 136 if (IS_ERR(f_ncm_inst)) 137 return PTR_ERR(f_ncm_inst); 138 139 ncm_opts = container_of(f_ncm_inst, struct f_ncm_opts, func_inst); 140 141 gether_set_qmult(ncm_opts->net, qmult); 142 if (!gether_set_host_addr(ncm_opts->net, host_addr)) 143 pr_info("using host ethernet address: %s", host_addr); 144 if (!gether_set_dev_addr(ncm_opts->net, dev_addr)) 145 pr_info("using self ethernet address: %s", dev_addr); 146 147 /* Allocate string descriptor numbers ... note that string 148 * contents can be overridden by the composite_dev glue. 149 */ 150 151 status = usb_string_ids_tab(cdev, strings_dev); 152 if (status < 0) 153 goto fail; 154 device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id; 155 device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id; 156 157 if (gadget_is_otg(gadget) && !otg_desc[0]) { 158 struct usb_descriptor_header *usb_desc; 159 160 usb_desc = usb_otg_descriptor_alloc(gadget); 161 if (!usb_desc) 162 goto fail; 163 usb_otg_descriptor_init(gadget, usb_desc); 164 otg_desc[0] = usb_desc; 165 otg_desc[1] = NULL; 166 } 167 168 status = usb_add_config(cdev, &ncm_config_driver, 169 ncm_do_config); 170 if (status < 0) 171 goto fail1; 172 173 usb_composite_overwrite_options(cdev, &coverwrite); 174 dev_info(&gadget->dev, "%s\n", DRIVER_DESC); 175 176 return 0; 177 178 fail1: 179 kfree(otg_desc[0]); 180 otg_desc[0] = NULL; 181 fail: 182 usb_put_function_instance(f_ncm_inst); 183 return status; 184 } 185 186 static int gncm_unbind(struct usb_composite_dev *cdev) 187 { 188 if (!IS_ERR_OR_NULL(f_ncm)) 189 usb_put_function(f_ncm); 190 if (!IS_ERR_OR_NULL(f_ncm_inst)) 191 usb_put_function_instance(f_ncm_inst); 192 kfree(otg_desc[0]); 193 otg_desc[0] = NULL; 194 195 return 0; 196 } 197 198 static struct usb_composite_driver ncm_driver = { 199 .name = "g_ncm", 200 .dev = &device_desc, 201 .strings = dev_strings, 202 .max_speed = USB_SPEED_HIGH, 203 .bind = gncm_bind, 204 .unbind = gncm_unbind, 205 }; 206 207 module_usb_composite_driver(ncm_driver); 208 209 MODULE_DESCRIPTION(DRIVER_DESC); 210 MODULE_AUTHOR("Yauheni Kaliuta"); 211 MODULE_LICENSE("GPL"); 212