1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * cdc2.c -- CDC Composite driver, with ECM and ACM support 4 * 5 * Copyright (C) 2008 David Brownell 6 * Copyright (C) 2008 Nokia Corporation 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 12 #include "u_ether.h" 13 #include "u_serial.h" 14 #include "u_ecm.h" 15 16 17 #define DRIVER_DESC "CDC Composite Gadget" 18 #define DRIVER_VERSION "King Kamehameha Day 2008" 19 20 /*-------------------------------------------------------------------------*/ 21 22 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!! 23 * Instead: allocate your own, using normal USB-IF procedures. 24 */ 25 26 /* Thanks to NetChip Technologies for donating this product ID. 27 * It's for devices with only this composite CDC configuration. 28 */ 29 #define CDC_VENDOR_NUM 0x0525 /* NetChip */ 30 #define CDC_PRODUCT_NUM 0xa4aa /* CDC Composite: ECM + ACM */ 31 32 USB_GADGET_COMPOSITE_OPTIONS(); 33 34 USB_ETHERNET_MODULE_PARAMETERS(); 35 36 /*-------------------------------------------------------------------------*/ 37 38 static struct usb_device_descriptor device_desc = { 39 .bLength = sizeof device_desc, 40 .bDescriptorType = USB_DT_DEVICE, 41 42 /* .bcdUSB = DYNAMIC */ 43 44 .bDeviceClass = USB_CLASS_COMM, 45 .bDeviceSubClass = 0, 46 .bDeviceProtocol = 0, 47 /* .bMaxPacketSize0 = f(hardware) */ 48 49 /* Vendor and product id can be overridden by module parameters. */ 50 .idVendor = cpu_to_le16(CDC_VENDOR_NUM), 51 .idProduct = cpu_to_le16(CDC_PRODUCT_NUM), 52 /* .bcdDevice = f(hardware) */ 53 /* .iManufacturer = DYNAMIC */ 54 /* .iProduct = DYNAMIC */ 55 /* NO SERIAL NUMBER */ 56 .bNumConfigurations = 1, 57 }; 58 59 static const struct usb_descriptor_header *otg_desc[2]; 60 61 /* string IDs are assigned dynamically */ 62 static struct usb_string strings_dev[] = { 63 [USB_GADGET_MANUFACTURER_IDX].s = "", 64 [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC, 65 [USB_GADGET_SERIAL_IDX].s = "", 66 { } /* end of list */ 67 }; 68 69 static struct usb_gadget_strings stringtab_dev = { 70 .language = 0x0409, /* en-us */ 71 .strings = strings_dev, 72 }; 73 74 static struct usb_gadget_strings *dev_strings[] = { 75 &stringtab_dev, 76 NULL, 77 }; 78 79 /*-------------------------------------------------------------------------*/ 80 static struct usb_function *f_acm; 81 static struct usb_function_instance *fi_serial; 82 83 static struct usb_function *f_ecm; 84 static struct usb_function_instance *fi_ecm; 85 86 /* 87 * We _always_ have both CDC ECM and CDC ACM functions. 88 */ 89 static int cdc_do_config(struct usb_configuration *c) 90 { 91 int status; 92 93 if (gadget_is_otg(c->cdev->gadget)) { 94 c->descriptors = otg_desc; 95 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP; 96 } 97 98 f_ecm = usb_get_function(fi_ecm); 99 if (IS_ERR(f_ecm)) { 100 status = PTR_ERR(f_ecm); 101 goto err_get_ecm; 102 } 103 104 status = usb_add_function(c, f_ecm); 105 if (status) 106 goto err_add_ecm; 107 108 f_acm = usb_get_function(fi_serial); 109 if (IS_ERR(f_acm)) { 110 status = PTR_ERR(f_acm); 111 goto err_get_acm; 112 } 113 114 status = usb_add_function(c, f_acm); 115 if (status) 116 goto err_add_acm; 117 return 0; 118 119 err_add_acm: 120 usb_put_function(f_acm); 121 err_get_acm: 122 usb_remove_function(c, f_ecm); 123 err_add_ecm: 124 usb_put_function(f_ecm); 125 err_get_ecm: 126 return status; 127 } 128 129 static struct usb_configuration cdc_config_driver = { 130 .label = "CDC Composite (ECM + ACM)", 131 .bConfigurationValue = 1, 132 /* .iConfiguration = DYNAMIC */ 133 .bmAttributes = USB_CONFIG_ATT_SELFPOWER, 134 }; 135 136 /*-------------------------------------------------------------------------*/ 137 138 static int cdc_bind(struct usb_composite_dev *cdev) 139 { 140 struct usb_gadget *gadget = cdev->gadget; 141 struct f_ecm_opts *ecm_opts; 142 int status; 143 144 if (!can_support_ecm(cdev->gadget)) { 145 dev_err(&gadget->dev, "controller '%s' not usable\n", 146 gadget->name); 147 return -EINVAL; 148 } 149 150 fi_ecm = usb_get_function_instance("ecm"); 151 if (IS_ERR(fi_ecm)) 152 return PTR_ERR(fi_ecm); 153 154 ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst); 155 156 gether_set_qmult(ecm_opts->net, qmult); 157 if (!gether_set_host_addr(ecm_opts->net, host_addr)) 158 pr_info("using host ethernet address: %s", host_addr); 159 if (!gether_set_dev_addr(ecm_opts->net, dev_addr)) 160 pr_info("using self ethernet address: %s", dev_addr); 161 162 fi_serial = usb_get_function_instance("acm"); 163 if (IS_ERR(fi_serial)) { 164 status = PTR_ERR(fi_serial); 165 goto fail; 166 } 167 168 /* Allocate string descriptor numbers ... note that string 169 * contents can be overridden by the composite_dev glue. 170 */ 171 172 status = usb_string_ids_tab(cdev, strings_dev); 173 if (status < 0) 174 goto fail1; 175 device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id; 176 device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id; 177 178 if (gadget_is_otg(gadget) && !otg_desc[0]) { 179 struct usb_descriptor_header *usb_desc; 180 181 usb_desc = usb_otg_descriptor_alloc(gadget); 182 if (!usb_desc) 183 goto fail1; 184 usb_otg_descriptor_init(gadget, usb_desc); 185 otg_desc[0] = usb_desc; 186 otg_desc[1] = NULL; 187 } 188 189 /* register our configuration */ 190 status = usb_add_config(cdev, &cdc_config_driver, cdc_do_config); 191 if (status < 0) 192 goto fail2; 193 194 usb_composite_overwrite_options(cdev, &coverwrite); 195 dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n", 196 DRIVER_DESC); 197 198 return 0; 199 200 fail2: 201 kfree(otg_desc[0]); 202 otg_desc[0] = NULL; 203 fail1: 204 usb_put_function_instance(fi_serial); 205 fail: 206 usb_put_function_instance(fi_ecm); 207 return status; 208 } 209 210 static int cdc_unbind(struct usb_composite_dev *cdev) 211 { 212 usb_put_function(f_acm); 213 usb_put_function_instance(fi_serial); 214 if (!IS_ERR_OR_NULL(f_ecm)) 215 usb_put_function(f_ecm); 216 if (!IS_ERR_OR_NULL(fi_ecm)) 217 usb_put_function_instance(fi_ecm); 218 kfree(otg_desc[0]); 219 otg_desc[0] = NULL; 220 221 return 0; 222 } 223 224 static struct usb_composite_driver cdc_driver = { 225 .name = "g_cdc", 226 .dev = &device_desc, 227 .strings = dev_strings, 228 .max_speed = USB_SPEED_HIGH, 229 .bind = cdc_bind, 230 .unbind = cdc_unbind, 231 }; 232 233 module_usb_composite_driver(cdc_driver); 234 235 MODULE_DESCRIPTION(DRIVER_DESC); 236 MODULE_AUTHOR("David Brownell"); 237 MODULE_LICENSE("GPL"); 238