Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 2 | /* |
| 3 | * u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack |
| 4 | * |
| 5 | * Copyright (C) 2003-2005,2008 David Brownell |
| 6 | * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger |
| 7 | * Copyright (C) 2008 Nokia Corporation |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 8 | */ |
| 9 | |
| 10 | /* #define VERBOSE_DEBUG */ |
| 11 | |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/gfp.h> |
| 15 | #include <linux/device.h> |
| 16 | #include <linux/ctype.h> |
| 17 | #include <linux/etherdevice.h> |
| 18 | #include <linux/ethtool.h> |
| 19 | #include <linux/if_vlan.h> |
| 20 | |
| 21 | #include "u_ether.h" |
| 22 | |
| 23 | |
| 24 | /* |
| 25 | * This component encapsulates the Ethernet link glue needed to provide |
| 26 | * one (!) network link through the USB gadget stack, normally "usb0". |
| 27 | * |
| 28 | * The control and data models are handled by the function driver which |
| 29 | * connects to this code; such as CDC Ethernet (ECM or EEM), |
| 30 | * "CDC Subset", or RNDIS. That includes all descriptor and endpoint |
| 31 | * management. |
| 32 | * |
| 33 | * Link level addressing is handled by this component using module |
| 34 | * parameters; if no such parameters are provided, random link level |
| 35 | * addresses are used. Each end of the link uses one address. The |
| 36 | * host end address is exported in various ways, and is often recorded |
| 37 | * in configuration databases. |
| 38 | * |
| 39 | * The driver which assembles each configuration using such a link is |
| 40 | * responsible for ensuring that each configuration includes at most one |
| 41 | * instance of is network link. (The network layer provides ways for |
| 42 | * this single "physical" link to be used by multiple virtual links.) |
| 43 | */ |
| 44 | |
| 45 | #define UETH__VERSION "29-May-2008" |
| 46 | |
| 47 | /* Experiments show that both Linux and Windows hosts allow up to 16k |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 48 | * frame sizes. Set the max MTU size to 15k+52 to prevent allocating 32k |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 49 | * blocks and still have efficient handling. */ |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 50 | #define GETHER_MAX_MTU_SIZE 15412 |
| 51 | #define GETHER_MAX_ETH_FRAME_LEN (GETHER_MAX_MTU_SIZE + ETH_HLEN) |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 52 | |
| 53 | struct eth_dev { |
| 54 | /* lock is held while accessing port_usb |
| 55 | */ |
| 56 | spinlock_t lock; |
| 57 | struct gether *port_usb; |
| 58 | |
| 59 | struct net_device *net; |
| 60 | struct usb_gadget *gadget; |
| 61 | |
| 62 | spinlock_t req_lock; /* guard {rx,tx}_reqs */ |
| 63 | struct list_head tx_reqs, rx_reqs; |
| 64 | atomic_t tx_qlen; |
| 65 | |
| 66 | struct sk_buff_head rx_frames; |
| 67 | |
| 68 | unsigned qmult; |
| 69 | |
| 70 | unsigned header_len; |
| 71 | struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb); |
| 72 | int (*unwrap)(struct gether *, |
| 73 | struct sk_buff *skb, |
| 74 | struct sk_buff_head *list); |
| 75 | |
| 76 | struct work_struct work; |
| 77 | |
| 78 | unsigned long todo; |
| 79 | #define WORK_RX_MEMORY 0 |
| 80 | |
| 81 | bool zlp; |
| 82 | bool no_skb_reserve; |
| 83 | u8 host_mac[ETH_ALEN]; |
| 84 | u8 dev_mac[ETH_ALEN]; |
| 85 | }; |
| 86 | |
| 87 | /*-------------------------------------------------------------------------*/ |
| 88 | |
| 89 | #define RX_EXTRA 20 /* bytes guarding against rx overflows */ |
| 90 | |
| 91 | #define DEFAULT_QLEN 2 /* double buffering by default */ |
| 92 | |
| 93 | /* for dual-speed hardware, use deeper queues at high/super speed */ |
| 94 | static inline int qlen(struct usb_gadget *gadget, unsigned qmult) |
| 95 | { |
| 96 | if (gadget_is_dualspeed(gadget) && (gadget->speed == USB_SPEED_HIGH || |
| 97 | gadget->speed >= USB_SPEED_SUPER)) |
| 98 | return qmult * DEFAULT_QLEN; |
| 99 | else |
| 100 | return DEFAULT_QLEN; |
| 101 | } |
| 102 | |
| 103 | /*-------------------------------------------------------------------------*/ |
| 104 | |
| 105 | /* REVISIT there must be a better way than having two sets |
| 106 | * of debug calls ... |
| 107 | */ |
| 108 | |
| 109 | #undef DBG |
| 110 | #undef VDBG |
| 111 | #undef ERROR |
| 112 | #undef INFO |
| 113 | |
| 114 | #define xprintk(d, level, fmt, args...) \ |
| 115 | printk(level "%s: " fmt , (d)->net->name , ## args) |
| 116 | |
| 117 | #ifdef DEBUG |
| 118 | #undef DEBUG |
| 119 | #define DBG(dev, fmt, args...) \ |
| 120 | xprintk(dev , KERN_DEBUG , fmt , ## args) |
| 121 | #else |
| 122 | #define DBG(dev, fmt, args...) \ |
| 123 | do { } while (0) |
| 124 | #endif /* DEBUG */ |
| 125 | |
| 126 | #ifdef VERBOSE_DEBUG |
| 127 | #define VDBG DBG |
| 128 | #else |
| 129 | #define VDBG(dev, fmt, args...) \ |
| 130 | do { } while (0) |
| 131 | #endif /* DEBUG */ |
| 132 | |
| 133 | #define ERROR(dev, fmt, args...) \ |
| 134 | xprintk(dev , KERN_ERR , fmt , ## args) |
| 135 | #define INFO(dev, fmt, args...) \ |
| 136 | xprintk(dev , KERN_INFO , fmt , ## args) |
| 137 | |
| 138 | /*-------------------------------------------------------------------------*/ |
| 139 | |
| 140 | /* NETWORK DRIVER HOOKUP (to the layer above this driver) */ |
| 141 | |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 142 | static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p) |
| 143 | { |
| 144 | struct eth_dev *dev = netdev_priv(net); |
| 145 | |
| 146 | strlcpy(p->driver, "g_ether", sizeof(p->driver)); |
| 147 | strlcpy(p->version, UETH__VERSION, sizeof(p->version)); |
| 148 | strlcpy(p->fw_version, dev->gadget->name, sizeof(p->fw_version)); |
| 149 | strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof(p->bus_info)); |
| 150 | } |
| 151 | |
| 152 | /* REVISIT can also support: |
| 153 | * - WOL (by tracking suspends and issuing remote wakeup) |
| 154 | * - msglevel (implies updated messaging) |
| 155 | * - ... probably more ethtool ops |
| 156 | */ |
| 157 | |
| 158 | static const struct ethtool_ops ops = { |
| 159 | .get_drvinfo = eth_get_drvinfo, |
| 160 | .get_link = ethtool_op_get_link, |
| 161 | }; |
| 162 | |
| 163 | static void defer_kevent(struct eth_dev *dev, int flag) |
| 164 | { |
| 165 | if (test_and_set_bit(flag, &dev->todo)) |
| 166 | return; |
| 167 | if (!schedule_work(&dev->work)) |
| 168 | ERROR(dev, "kevent %d may have been dropped\n", flag); |
| 169 | else |
| 170 | DBG(dev, "kevent %d scheduled\n", flag); |
| 171 | } |
| 172 | |
| 173 | static void rx_complete(struct usb_ep *ep, struct usb_request *req); |
| 174 | |
| 175 | static int |
| 176 | rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags) |
| 177 | { |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 178 | struct usb_gadget *g = dev->gadget; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 179 | struct sk_buff *skb; |
| 180 | int retval = -ENOMEM; |
| 181 | size_t size = 0; |
| 182 | struct usb_ep *out; |
| 183 | unsigned long flags; |
| 184 | |
| 185 | spin_lock_irqsave(&dev->lock, flags); |
| 186 | if (dev->port_usb) |
| 187 | out = dev->port_usb->out_ep; |
| 188 | else |
| 189 | out = NULL; |
| 190 | |
| 191 | if (!out) |
| 192 | { |
| 193 | spin_unlock_irqrestore(&dev->lock, flags); |
| 194 | return -ENOTCONN; |
| 195 | } |
| 196 | |
| 197 | /* Padding up to RX_EXTRA handles minor disagreements with host. |
| 198 | * Normally we use the USB "terminate on short read" convention; |
| 199 | * so allow up to (N*maxpacket), since that memory is normally |
| 200 | * already allocated. Some hardware doesn't deal well with short |
| 201 | * reads (e.g. DMA must be N*maxpacket), so for now don't trim a |
| 202 | * byte off the end (to force hardware errors on overflow). |
| 203 | * |
| 204 | * RNDIS uses internal framing, and explicitly allows senders to |
| 205 | * pad to end-of-packet. That's potentially nice for speed, but |
| 206 | * means receivers can't recover lost synch on their own (because |
| 207 | * new packets don't only start after a short RX). |
| 208 | */ |
| 209 | size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA; |
| 210 | size += dev->port_usb->header_len; |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 211 | |
| 212 | if (g->quirk_ep_out_aligned_size) { |
| 213 | size += out->maxpacket - 1; |
| 214 | size -= size % out->maxpacket; |
| 215 | } |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 216 | |
| 217 | if (dev->port_usb->is_fixed) |
| 218 | size = max_t(size_t, size, dev->port_usb->fixed_out_len); |
| 219 | spin_unlock_irqrestore(&dev->lock, flags); |
| 220 | |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 221 | skb = __netdev_alloc_skb(dev->net, size + NET_IP_ALIGN, gfp_flags); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 222 | if (skb == NULL) { |
| 223 | DBG(dev, "no rx skb\n"); |
| 224 | goto enomem; |
| 225 | } |
| 226 | |
| 227 | /* Some platforms perform better when IP packets are aligned, |
| 228 | * but on at least one, checksumming fails otherwise. Note: |
| 229 | * RNDIS headers involve variable numbers of LE32 values. |
| 230 | */ |
| 231 | if (likely(!dev->no_skb_reserve)) |
| 232 | skb_reserve(skb, NET_IP_ALIGN); |
| 233 | |
| 234 | req->buf = skb->data; |
| 235 | req->length = size; |
| 236 | req->complete = rx_complete; |
| 237 | req->context = skb; |
| 238 | |
| 239 | retval = usb_ep_queue(out, req, gfp_flags); |
| 240 | if (retval == -ENOMEM) |
| 241 | enomem: |
| 242 | defer_kevent(dev, WORK_RX_MEMORY); |
| 243 | if (retval) { |
| 244 | DBG(dev, "rx submit --> %d\n", retval); |
| 245 | if (skb) |
| 246 | dev_kfree_skb_any(skb); |
| 247 | spin_lock_irqsave(&dev->req_lock, flags); |
| 248 | list_add(&req->list, &dev->rx_reqs); |
| 249 | spin_unlock_irqrestore(&dev->req_lock, flags); |
| 250 | } |
| 251 | return retval; |
| 252 | } |
| 253 | |
| 254 | static void rx_complete(struct usb_ep *ep, struct usb_request *req) |
| 255 | { |
| 256 | struct sk_buff *skb = req->context, *skb2; |
| 257 | struct eth_dev *dev = ep->driver_data; |
| 258 | int status = req->status; |
| 259 | |
| 260 | switch (status) { |
| 261 | |
| 262 | /* normal completion */ |
| 263 | case 0: |
| 264 | skb_put(skb, req->actual); |
| 265 | |
| 266 | if (dev->unwrap) { |
| 267 | unsigned long flags; |
| 268 | |
| 269 | spin_lock_irqsave(&dev->lock, flags); |
| 270 | if (dev->port_usb) { |
| 271 | status = dev->unwrap(dev->port_usb, |
| 272 | skb, |
| 273 | &dev->rx_frames); |
| 274 | } else { |
| 275 | dev_kfree_skb_any(skb); |
| 276 | status = -ENOTCONN; |
| 277 | } |
| 278 | spin_unlock_irqrestore(&dev->lock, flags); |
| 279 | } else { |
| 280 | skb_queue_tail(&dev->rx_frames, skb); |
| 281 | } |
| 282 | skb = NULL; |
| 283 | |
| 284 | skb2 = skb_dequeue(&dev->rx_frames); |
| 285 | while (skb2) { |
| 286 | if (status < 0 |
| 287 | || ETH_HLEN > skb2->len |
| 288 | || skb2->len > GETHER_MAX_ETH_FRAME_LEN) { |
| 289 | dev->net->stats.rx_errors++; |
| 290 | dev->net->stats.rx_length_errors++; |
| 291 | DBG(dev, "rx length %d\n", skb2->len); |
| 292 | dev_kfree_skb_any(skb2); |
| 293 | goto next_frame; |
| 294 | } |
| 295 | skb2->protocol = eth_type_trans(skb2, dev->net); |
| 296 | dev->net->stats.rx_packets++; |
| 297 | dev->net->stats.rx_bytes += skb2->len; |
| 298 | |
| 299 | /* no buffer copies needed, unless hardware can't |
| 300 | * use skb buffers. |
| 301 | */ |
| 302 | status = netif_rx(skb2); |
| 303 | next_frame: |
| 304 | skb2 = skb_dequeue(&dev->rx_frames); |
| 305 | } |
| 306 | break; |
| 307 | |
| 308 | /* software-driven interface shutdown */ |
| 309 | case -ECONNRESET: /* unlink */ |
| 310 | case -ESHUTDOWN: /* disconnect etc */ |
| 311 | VDBG(dev, "rx shutdown, code %d\n", status); |
| 312 | goto quiesce; |
| 313 | |
| 314 | /* for hardware automagic (such as pxa) */ |
| 315 | case -ECONNABORTED: /* endpoint reset */ |
| 316 | DBG(dev, "rx %s reset\n", ep->name); |
| 317 | defer_kevent(dev, WORK_RX_MEMORY); |
| 318 | quiesce: |
| 319 | dev_kfree_skb_any(skb); |
| 320 | goto clean; |
| 321 | |
| 322 | /* data overrun */ |
| 323 | case -EOVERFLOW: |
| 324 | dev->net->stats.rx_over_errors++; |
| 325 | /* FALLTHROUGH */ |
| 326 | |
| 327 | default: |
| 328 | dev->net->stats.rx_errors++; |
| 329 | DBG(dev, "rx status %d\n", status); |
| 330 | break; |
| 331 | } |
| 332 | |
| 333 | if (skb) |
| 334 | dev_kfree_skb_any(skb); |
| 335 | if (!netif_running(dev->net)) { |
| 336 | clean: |
| 337 | spin_lock(&dev->req_lock); |
| 338 | list_add(&req->list, &dev->rx_reqs); |
| 339 | spin_unlock(&dev->req_lock); |
| 340 | req = NULL; |
| 341 | } |
| 342 | if (req) |
| 343 | rx_submit(dev, req, GFP_ATOMIC); |
| 344 | } |
| 345 | |
| 346 | static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n) |
| 347 | { |
| 348 | unsigned i; |
| 349 | struct usb_request *req; |
| 350 | |
| 351 | if (!n) |
| 352 | return -ENOMEM; |
| 353 | |
| 354 | /* queue/recycle up to N requests */ |
| 355 | i = n; |
| 356 | list_for_each_entry(req, list, list) { |
| 357 | if (i-- == 0) |
| 358 | goto extra; |
| 359 | } |
| 360 | while (i--) { |
| 361 | req = usb_ep_alloc_request(ep, GFP_ATOMIC); |
| 362 | if (!req) |
| 363 | return list_empty(list) ? -ENOMEM : 0; |
| 364 | list_add(&req->list, list); |
| 365 | } |
| 366 | return 0; |
| 367 | |
| 368 | extra: |
| 369 | /* free extras */ |
| 370 | for (;;) { |
| 371 | struct list_head *next; |
| 372 | |
| 373 | next = req->list.next; |
| 374 | list_del(&req->list); |
| 375 | usb_ep_free_request(ep, req); |
| 376 | |
| 377 | if (next == list) |
| 378 | break; |
| 379 | |
| 380 | req = container_of(next, struct usb_request, list); |
| 381 | } |
| 382 | return 0; |
| 383 | } |
| 384 | |
| 385 | static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n) |
| 386 | { |
| 387 | int status; |
| 388 | |
| 389 | spin_lock(&dev->req_lock); |
| 390 | status = prealloc(&dev->tx_reqs, link->in_ep, n); |
| 391 | if (status < 0) |
| 392 | goto fail; |
| 393 | status = prealloc(&dev->rx_reqs, link->out_ep, n); |
| 394 | if (status < 0) |
| 395 | goto fail; |
| 396 | goto done; |
| 397 | fail: |
| 398 | DBG(dev, "can't alloc requests\n"); |
| 399 | done: |
| 400 | spin_unlock(&dev->req_lock); |
| 401 | return status; |
| 402 | } |
| 403 | |
| 404 | static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags) |
| 405 | { |
| 406 | struct usb_request *req; |
| 407 | unsigned long flags; |
| 408 | |
| 409 | /* fill unused rxq slots with some skb */ |
| 410 | spin_lock_irqsave(&dev->req_lock, flags); |
| 411 | while (!list_empty(&dev->rx_reqs)) { |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 412 | req = list_first_entry(&dev->rx_reqs, struct usb_request, list); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 413 | list_del_init(&req->list); |
| 414 | spin_unlock_irqrestore(&dev->req_lock, flags); |
| 415 | |
| 416 | if (rx_submit(dev, req, gfp_flags) < 0) { |
| 417 | defer_kevent(dev, WORK_RX_MEMORY); |
| 418 | return; |
| 419 | } |
| 420 | |
| 421 | spin_lock_irqsave(&dev->req_lock, flags); |
| 422 | } |
| 423 | spin_unlock_irqrestore(&dev->req_lock, flags); |
| 424 | } |
| 425 | |
| 426 | static void eth_work(struct work_struct *work) |
| 427 | { |
| 428 | struct eth_dev *dev = container_of(work, struct eth_dev, work); |
| 429 | |
| 430 | if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) { |
| 431 | if (netif_running(dev->net)) |
| 432 | rx_fill(dev, GFP_KERNEL); |
| 433 | } |
| 434 | |
| 435 | if (dev->todo) |
| 436 | DBG(dev, "work done, flags = 0x%lx\n", dev->todo); |
| 437 | } |
| 438 | |
| 439 | static void tx_complete(struct usb_ep *ep, struct usb_request *req) |
| 440 | { |
| 441 | struct sk_buff *skb = req->context; |
| 442 | struct eth_dev *dev = ep->driver_data; |
| 443 | |
| 444 | switch (req->status) { |
| 445 | default: |
| 446 | dev->net->stats.tx_errors++; |
| 447 | VDBG(dev, "tx err %d\n", req->status); |
| 448 | /* FALLTHROUGH */ |
| 449 | case -ECONNRESET: /* unlink */ |
| 450 | case -ESHUTDOWN: /* disconnect etc */ |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 451 | dev_kfree_skb_any(skb); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 452 | break; |
| 453 | case 0: |
| 454 | dev->net->stats.tx_bytes += skb->len; |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 455 | dev_consume_skb_any(skb); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 456 | } |
| 457 | dev->net->stats.tx_packets++; |
| 458 | |
| 459 | spin_lock(&dev->req_lock); |
| 460 | list_add(&req->list, &dev->tx_reqs); |
| 461 | spin_unlock(&dev->req_lock); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 462 | |
| 463 | atomic_dec(&dev->tx_qlen); |
| 464 | if (netif_carrier_ok(dev->net)) |
| 465 | netif_wake_queue(dev->net); |
| 466 | } |
| 467 | |
| 468 | static inline int is_promisc(u16 cdc_filter) |
| 469 | { |
| 470 | return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS; |
| 471 | } |
| 472 | |
| 473 | static netdev_tx_t eth_start_xmit(struct sk_buff *skb, |
| 474 | struct net_device *net) |
| 475 | { |
| 476 | struct eth_dev *dev = netdev_priv(net); |
| 477 | int length = 0; |
| 478 | int retval; |
| 479 | struct usb_request *req = NULL; |
| 480 | unsigned long flags; |
| 481 | struct usb_ep *in; |
| 482 | u16 cdc_filter; |
| 483 | |
| 484 | spin_lock_irqsave(&dev->lock, flags); |
| 485 | if (dev->port_usb) { |
| 486 | in = dev->port_usb->in_ep; |
| 487 | cdc_filter = dev->port_usb->cdc_filter; |
| 488 | } else { |
| 489 | in = NULL; |
| 490 | cdc_filter = 0; |
| 491 | } |
| 492 | spin_unlock_irqrestore(&dev->lock, flags); |
| 493 | |
Googler | b48fa91 | 2023-03-17 12:40:29 +0530 | [diff] [blame^] | 494 | if (skb && !in) { |
| 495 | dev_kfree_skb_any(skb); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 496 | return NETDEV_TX_OK; |
| 497 | } |
| 498 | |
| 499 | /* apply outgoing CDC or RNDIS filters */ |
| 500 | if (skb && !is_promisc(cdc_filter)) { |
| 501 | u8 *dest = skb->data; |
| 502 | |
| 503 | if (is_multicast_ether_addr(dest)) { |
| 504 | u16 type; |
| 505 | |
| 506 | /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host |
| 507 | * SET_ETHERNET_MULTICAST_FILTERS requests |
| 508 | */ |
| 509 | if (is_broadcast_ether_addr(dest)) |
| 510 | type = USB_CDC_PACKET_TYPE_BROADCAST; |
| 511 | else |
| 512 | type = USB_CDC_PACKET_TYPE_ALL_MULTICAST; |
| 513 | if (!(cdc_filter & type)) { |
| 514 | dev_kfree_skb_any(skb); |
| 515 | return NETDEV_TX_OK; |
| 516 | } |
| 517 | } |
| 518 | /* ignores USB_CDC_PACKET_TYPE_DIRECTED */ |
| 519 | } |
| 520 | |
| 521 | spin_lock_irqsave(&dev->req_lock, flags); |
| 522 | /* |
| 523 | * this freelist can be empty if an interrupt triggered disconnect() |
| 524 | * and reconfigured the gadget (shutting down this queue) after the |
| 525 | * network stack decided to xmit but before we got the spinlock. |
| 526 | */ |
| 527 | if (list_empty(&dev->tx_reqs)) { |
| 528 | spin_unlock_irqrestore(&dev->req_lock, flags); |
| 529 | return NETDEV_TX_BUSY; |
| 530 | } |
| 531 | |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 532 | req = list_first_entry(&dev->tx_reqs, struct usb_request, list); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 533 | list_del(&req->list); |
| 534 | |
| 535 | /* temporarily stop TX queue when the freelist empties */ |
| 536 | if (list_empty(&dev->tx_reqs)) |
| 537 | netif_stop_queue(net); |
| 538 | spin_unlock_irqrestore(&dev->req_lock, flags); |
| 539 | |
| 540 | /* no buffer copies needed, unless the network stack did it |
| 541 | * or the hardware can't use skb buffers. |
| 542 | * or there's not enough space for extra headers we need |
| 543 | */ |
| 544 | if (dev->wrap) { |
| 545 | unsigned long flags; |
| 546 | |
| 547 | spin_lock_irqsave(&dev->lock, flags); |
| 548 | if (dev->port_usb) |
| 549 | skb = dev->wrap(dev->port_usb, skb); |
| 550 | spin_unlock_irqrestore(&dev->lock, flags); |
| 551 | if (!skb) { |
| 552 | /* Multi frame CDC protocols may store the frame for |
| 553 | * later which is not a dropped frame. |
| 554 | */ |
| 555 | if (dev->port_usb && |
| 556 | dev->port_usb->supports_multi_frame) |
| 557 | goto multiframe; |
| 558 | goto drop; |
| 559 | } |
| 560 | } |
| 561 | |
| 562 | length = skb->len; |
| 563 | req->buf = skb->data; |
| 564 | req->context = skb; |
| 565 | req->complete = tx_complete; |
| 566 | |
| 567 | /* NCM requires no zlp if transfer is dwNtbInMaxSize */ |
| 568 | if (dev->port_usb && |
| 569 | dev->port_usb->is_fixed && |
| 570 | length == dev->port_usb->fixed_in_len && |
| 571 | (length % in->maxpacket) == 0) |
| 572 | req->zero = 0; |
| 573 | else |
| 574 | req->zero = 1; |
| 575 | |
| 576 | /* use zlp framing on tx for strict CDC-Ether conformance, |
| 577 | * though any robust network rx path ignores extra padding. |
| 578 | * and some hardware doesn't like to write zlps. |
| 579 | */ |
| 580 | if (req->zero && !dev->zlp && (length % in->maxpacket) == 0) |
| 581 | length++; |
| 582 | |
| 583 | req->length = length; |
| 584 | |
| 585 | retval = usb_ep_queue(in, req, GFP_ATOMIC); |
| 586 | switch (retval) { |
| 587 | default: |
| 588 | DBG(dev, "tx queue err %d\n", retval); |
| 589 | break; |
| 590 | case 0: |
| 591 | netif_trans_update(net); |
| 592 | atomic_inc(&dev->tx_qlen); |
| 593 | } |
| 594 | |
| 595 | if (retval) { |
| 596 | dev_kfree_skb_any(skb); |
| 597 | drop: |
| 598 | dev->net->stats.tx_dropped++; |
| 599 | multiframe: |
| 600 | spin_lock_irqsave(&dev->req_lock, flags); |
| 601 | if (list_empty(&dev->tx_reqs)) |
| 602 | netif_start_queue(net); |
| 603 | list_add(&req->list, &dev->tx_reqs); |
| 604 | spin_unlock_irqrestore(&dev->req_lock, flags); |
| 605 | } |
| 606 | return NETDEV_TX_OK; |
| 607 | } |
| 608 | |
| 609 | /*-------------------------------------------------------------------------*/ |
| 610 | |
| 611 | static void eth_start(struct eth_dev *dev, gfp_t gfp_flags) |
| 612 | { |
| 613 | DBG(dev, "%s\n", __func__); |
| 614 | |
| 615 | /* fill the rx queue */ |
| 616 | rx_fill(dev, gfp_flags); |
| 617 | |
| 618 | /* and open the tx floodgates */ |
| 619 | atomic_set(&dev->tx_qlen, 0); |
| 620 | netif_wake_queue(dev->net); |
| 621 | } |
| 622 | |
| 623 | static int eth_open(struct net_device *net) |
| 624 | { |
| 625 | struct eth_dev *dev = netdev_priv(net); |
| 626 | struct gether *link; |
| 627 | |
| 628 | DBG(dev, "%s\n", __func__); |
| 629 | if (netif_carrier_ok(dev->net)) |
| 630 | eth_start(dev, GFP_KERNEL); |
| 631 | |
| 632 | spin_lock_irq(&dev->lock); |
| 633 | link = dev->port_usb; |
| 634 | if (link && link->open) |
| 635 | link->open(link); |
| 636 | spin_unlock_irq(&dev->lock); |
| 637 | |
| 638 | return 0; |
| 639 | } |
| 640 | |
| 641 | static int eth_stop(struct net_device *net) |
| 642 | { |
| 643 | struct eth_dev *dev = netdev_priv(net); |
| 644 | unsigned long flags; |
| 645 | |
| 646 | VDBG(dev, "%s\n", __func__); |
| 647 | netif_stop_queue(net); |
| 648 | |
| 649 | DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n", |
| 650 | dev->net->stats.rx_packets, dev->net->stats.tx_packets, |
| 651 | dev->net->stats.rx_errors, dev->net->stats.tx_errors |
| 652 | ); |
| 653 | |
| 654 | /* ensure there are no more active requests */ |
| 655 | spin_lock_irqsave(&dev->lock, flags); |
| 656 | if (dev->port_usb) { |
| 657 | struct gether *link = dev->port_usb; |
| 658 | const struct usb_endpoint_descriptor *in; |
| 659 | const struct usb_endpoint_descriptor *out; |
| 660 | |
| 661 | if (link->close) |
| 662 | link->close(link); |
| 663 | |
| 664 | /* NOTE: we have no abort-queue primitive we could use |
| 665 | * to cancel all pending I/O. Instead, we disable then |
| 666 | * reenable the endpoints ... this idiom may leave toggle |
| 667 | * wrong, but that's a self-correcting error. |
| 668 | * |
| 669 | * REVISIT: we *COULD* just let the transfers complete at |
| 670 | * their own pace; the network stack can handle old packets. |
| 671 | * For the moment we leave this here, since it works. |
| 672 | */ |
| 673 | in = link->in_ep->desc; |
| 674 | out = link->out_ep->desc; |
| 675 | usb_ep_disable(link->in_ep); |
| 676 | usb_ep_disable(link->out_ep); |
| 677 | if (netif_carrier_ok(net)) { |
| 678 | DBG(dev, "host still using in/out endpoints\n"); |
| 679 | link->in_ep->desc = in; |
| 680 | link->out_ep->desc = out; |
| 681 | usb_ep_enable(link->in_ep); |
| 682 | usb_ep_enable(link->out_ep); |
| 683 | } |
| 684 | } |
| 685 | spin_unlock_irqrestore(&dev->lock, flags); |
| 686 | |
| 687 | return 0; |
| 688 | } |
| 689 | |
| 690 | /*-------------------------------------------------------------------------*/ |
| 691 | |
| 692 | static int get_ether_addr(const char *str, u8 *dev_addr) |
| 693 | { |
| 694 | if (str) { |
| 695 | unsigned i; |
| 696 | |
| 697 | for (i = 0; i < 6; i++) { |
| 698 | unsigned char num; |
| 699 | |
| 700 | if ((*str == '.') || (*str == ':')) |
| 701 | str++; |
| 702 | num = hex_to_bin(*str++) << 4; |
| 703 | num |= hex_to_bin(*str++); |
| 704 | dev_addr [i] = num; |
| 705 | } |
| 706 | if (is_valid_ether_addr(dev_addr)) |
| 707 | return 0; |
| 708 | } |
| 709 | eth_random_addr(dev_addr); |
| 710 | return 1; |
| 711 | } |
| 712 | |
| 713 | static int get_ether_addr_str(u8 dev_addr[ETH_ALEN], char *str, int len) |
| 714 | { |
| 715 | if (len < 18) |
| 716 | return -EINVAL; |
| 717 | |
| 718 | snprintf(str, len, "%pM", dev_addr); |
| 719 | return 18; |
| 720 | } |
| 721 | |
| 722 | static const struct net_device_ops eth_netdev_ops = { |
| 723 | .ndo_open = eth_open, |
| 724 | .ndo_stop = eth_stop, |
| 725 | .ndo_start_xmit = eth_start_xmit, |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 726 | .ndo_set_mac_address = eth_mac_addr, |
| 727 | .ndo_validate_addr = eth_validate_addr, |
| 728 | }; |
| 729 | |
| 730 | static struct device_type gadget_type = { |
| 731 | .name = "gadget", |
| 732 | }; |
| 733 | |
| 734 | /** |
| 735 | * gether_setup_name - initialize one ethernet-over-usb link |
| 736 | * @g: gadget to associated with these links |
| 737 | * @ethaddr: NULL, or a buffer in which the ethernet address of the |
| 738 | * host side of the link is recorded |
| 739 | * @netname: name for network device (for example, "usb") |
| 740 | * Context: may sleep |
| 741 | * |
| 742 | * This sets up the single network link that may be exported by a |
| 743 | * gadget driver using this framework. The link layer addresses are |
| 744 | * set up using module parameters. |
| 745 | * |
| 746 | * Returns an eth_dev pointer on success, or an ERR_PTR on failure. |
| 747 | */ |
| 748 | struct eth_dev *gether_setup_name(struct usb_gadget *g, |
| 749 | const char *dev_addr, const char *host_addr, |
| 750 | u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname) |
| 751 | { |
| 752 | struct eth_dev *dev; |
| 753 | struct net_device *net; |
| 754 | int status; |
| 755 | |
| 756 | net = alloc_etherdev(sizeof *dev); |
| 757 | if (!net) |
| 758 | return ERR_PTR(-ENOMEM); |
| 759 | |
| 760 | dev = netdev_priv(net); |
| 761 | spin_lock_init(&dev->lock); |
| 762 | spin_lock_init(&dev->req_lock); |
| 763 | INIT_WORK(&dev->work, eth_work); |
| 764 | INIT_LIST_HEAD(&dev->tx_reqs); |
| 765 | INIT_LIST_HEAD(&dev->rx_reqs); |
| 766 | |
| 767 | skb_queue_head_init(&dev->rx_frames); |
| 768 | |
| 769 | /* network device setup */ |
| 770 | dev->net = net; |
| 771 | dev->qmult = qmult; |
| 772 | snprintf(net->name, sizeof(net->name), "%s%%d", netname); |
| 773 | |
Googler | b48fa91 | 2023-03-17 12:40:29 +0530 | [diff] [blame^] | 774 | if (get_ether_addr(dev_addr, net->dev_addr)) |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 775 | dev_warn(&g->dev, |
| 776 | "using random %s ethernet address\n", "self"); |
| 777 | if (get_ether_addr(host_addr, dev->host_mac)) |
| 778 | dev_warn(&g->dev, |
| 779 | "using random %s ethernet address\n", "host"); |
| 780 | |
| 781 | if (ethaddr) |
| 782 | memcpy(ethaddr, dev->host_mac, ETH_ALEN); |
| 783 | |
| 784 | net->netdev_ops = ð_netdev_ops; |
| 785 | |
| 786 | net->ethtool_ops = &ops; |
| 787 | |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 788 | /* MTU range: 14 - 15412 */ |
| 789 | net->min_mtu = ETH_HLEN; |
| 790 | net->max_mtu = GETHER_MAX_MTU_SIZE; |
| 791 | |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 792 | dev->gadget = g; |
| 793 | SET_NETDEV_DEV(net, &g->dev); |
| 794 | SET_NETDEV_DEVTYPE(net, &gadget_type); |
| 795 | |
| 796 | status = register_netdev(net); |
| 797 | if (status < 0) { |
| 798 | dev_dbg(&g->dev, "register_netdev failed, %d\n", status); |
| 799 | free_netdev(net); |
| 800 | dev = ERR_PTR(status); |
| 801 | } else { |
| 802 | INFO(dev, "MAC %pM\n", net->dev_addr); |
| 803 | INFO(dev, "HOST MAC %pM\n", dev->host_mac); |
| 804 | |
| 805 | /* |
| 806 | * two kinds of host-initiated state changes: |
| 807 | * - iff DATA transfer is active, carrier is "on" |
| 808 | * - tx queueing enabled if open *and* carrier is "on" |
| 809 | */ |
| 810 | netif_carrier_off(net); |
| 811 | } |
| 812 | |
| 813 | return dev; |
| 814 | } |
| 815 | EXPORT_SYMBOL_GPL(gether_setup_name); |
| 816 | |
| 817 | struct net_device *gether_setup_name_default(const char *netname) |
| 818 | { |
| 819 | struct net_device *net; |
| 820 | struct eth_dev *dev; |
| 821 | |
| 822 | net = alloc_etherdev(sizeof(*dev)); |
| 823 | if (!net) |
| 824 | return ERR_PTR(-ENOMEM); |
| 825 | |
| 826 | dev = netdev_priv(net); |
| 827 | spin_lock_init(&dev->lock); |
| 828 | spin_lock_init(&dev->req_lock); |
| 829 | INIT_WORK(&dev->work, eth_work); |
| 830 | INIT_LIST_HEAD(&dev->tx_reqs); |
| 831 | INIT_LIST_HEAD(&dev->rx_reqs); |
| 832 | |
| 833 | skb_queue_head_init(&dev->rx_frames); |
| 834 | |
| 835 | /* network device setup */ |
| 836 | dev->net = net; |
| 837 | dev->qmult = QMULT_DEFAULT; |
| 838 | snprintf(net->name, sizeof(net->name), "%s%%d", netname); |
| 839 | |
| 840 | eth_random_addr(dev->dev_mac); |
| 841 | pr_warn("using random %s ethernet address\n", "self"); |
| 842 | eth_random_addr(dev->host_mac); |
| 843 | pr_warn("using random %s ethernet address\n", "host"); |
| 844 | |
| 845 | net->netdev_ops = ð_netdev_ops; |
| 846 | |
| 847 | net->ethtool_ops = &ops; |
| 848 | SET_NETDEV_DEVTYPE(net, &gadget_type); |
| 849 | |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 850 | /* MTU range: 14 - 15412 */ |
| 851 | net->min_mtu = ETH_HLEN; |
| 852 | net->max_mtu = GETHER_MAX_MTU_SIZE; |
| 853 | |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 854 | return net; |
| 855 | } |
| 856 | EXPORT_SYMBOL_GPL(gether_setup_name_default); |
| 857 | |
| 858 | int gether_register_netdev(struct net_device *net) |
| 859 | { |
| 860 | struct eth_dev *dev; |
| 861 | struct usb_gadget *g; |
Googler | b48fa91 | 2023-03-17 12:40:29 +0530 | [diff] [blame^] | 862 | struct sockaddr sa; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 863 | int status; |
| 864 | |
| 865 | if (!net->dev.parent) |
| 866 | return -EINVAL; |
| 867 | dev = netdev_priv(net); |
| 868 | g = dev->gadget; |
| 869 | status = register_netdev(net); |
| 870 | if (status < 0) { |
| 871 | dev_dbg(&g->dev, "register_netdev failed, %d\n", status); |
| 872 | return status; |
| 873 | } else { |
| 874 | INFO(dev, "HOST MAC %pM\n", dev->host_mac); |
| 875 | |
| 876 | /* two kinds of host-initiated state changes: |
| 877 | * - iff DATA transfer is active, carrier is "on" |
| 878 | * - tx queueing enabled if open *and* carrier is "on" |
| 879 | */ |
| 880 | netif_carrier_off(net); |
| 881 | } |
Googler | b48fa91 | 2023-03-17 12:40:29 +0530 | [diff] [blame^] | 882 | sa.sa_family = net->type; |
| 883 | memcpy(sa.sa_data, dev->dev_mac, ETH_ALEN); |
| 884 | rtnl_lock(); |
| 885 | status = dev_set_mac_address(net, &sa, NULL); |
| 886 | rtnl_unlock(); |
| 887 | if (status) |
| 888 | pr_warn("cannot set self ethernet address: %d\n", status); |
| 889 | else |
| 890 | INFO(dev, "MAC %pM\n", dev->dev_mac); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 891 | |
| 892 | return status; |
| 893 | } |
| 894 | EXPORT_SYMBOL_GPL(gether_register_netdev); |
| 895 | |
| 896 | void gether_set_gadget(struct net_device *net, struct usb_gadget *g) |
| 897 | { |
| 898 | struct eth_dev *dev; |
| 899 | |
| 900 | dev = netdev_priv(net); |
| 901 | dev->gadget = g; |
| 902 | SET_NETDEV_DEV(net, &g->dev); |
| 903 | } |
| 904 | EXPORT_SYMBOL_GPL(gether_set_gadget); |
| 905 | |
| 906 | int gether_set_dev_addr(struct net_device *net, const char *dev_addr) |
| 907 | { |
| 908 | struct eth_dev *dev; |
| 909 | u8 new_addr[ETH_ALEN]; |
| 910 | |
| 911 | dev = netdev_priv(net); |
| 912 | if (get_ether_addr(dev_addr, new_addr)) |
| 913 | return -EINVAL; |
| 914 | memcpy(dev->dev_mac, new_addr, ETH_ALEN); |
| 915 | return 0; |
| 916 | } |
| 917 | EXPORT_SYMBOL_GPL(gether_set_dev_addr); |
| 918 | |
| 919 | int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len) |
| 920 | { |
| 921 | struct eth_dev *dev; |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 922 | int ret; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 923 | |
| 924 | dev = netdev_priv(net); |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 925 | ret = get_ether_addr_str(dev->dev_mac, dev_addr, len); |
| 926 | if (ret + 1 < len) { |
| 927 | dev_addr[ret++] = '\n'; |
| 928 | dev_addr[ret] = '\0'; |
| 929 | } |
| 930 | |
| 931 | return ret; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 932 | } |
| 933 | EXPORT_SYMBOL_GPL(gether_get_dev_addr); |
| 934 | |
| 935 | int gether_set_host_addr(struct net_device *net, const char *host_addr) |
| 936 | { |
| 937 | struct eth_dev *dev; |
| 938 | u8 new_addr[ETH_ALEN]; |
| 939 | |
| 940 | dev = netdev_priv(net); |
| 941 | if (get_ether_addr(host_addr, new_addr)) |
| 942 | return -EINVAL; |
| 943 | memcpy(dev->host_mac, new_addr, ETH_ALEN); |
| 944 | return 0; |
| 945 | } |
| 946 | EXPORT_SYMBOL_GPL(gether_set_host_addr); |
| 947 | |
| 948 | int gether_get_host_addr(struct net_device *net, char *host_addr, int len) |
| 949 | { |
| 950 | struct eth_dev *dev; |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 951 | int ret; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 952 | |
| 953 | dev = netdev_priv(net); |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 954 | ret = get_ether_addr_str(dev->host_mac, host_addr, len); |
| 955 | if (ret + 1 < len) { |
| 956 | host_addr[ret++] = '\n'; |
| 957 | host_addr[ret] = '\0'; |
| 958 | } |
| 959 | |
| 960 | return ret; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 961 | } |
| 962 | EXPORT_SYMBOL_GPL(gether_get_host_addr); |
| 963 | |
| 964 | int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len) |
| 965 | { |
| 966 | struct eth_dev *dev; |
| 967 | |
| 968 | if (len < 13) |
| 969 | return -EINVAL; |
| 970 | |
| 971 | dev = netdev_priv(net); |
| 972 | snprintf(host_addr, len, "%pm", dev->host_mac); |
| 973 | |
| 974 | return strlen(host_addr); |
| 975 | } |
| 976 | EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc); |
| 977 | |
| 978 | void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN]) |
| 979 | { |
| 980 | struct eth_dev *dev; |
| 981 | |
| 982 | dev = netdev_priv(net); |
| 983 | memcpy(host_mac, dev->host_mac, ETH_ALEN); |
| 984 | } |
| 985 | EXPORT_SYMBOL_GPL(gether_get_host_addr_u8); |
| 986 | |
| 987 | void gether_set_qmult(struct net_device *net, unsigned qmult) |
| 988 | { |
| 989 | struct eth_dev *dev; |
| 990 | |
| 991 | dev = netdev_priv(net); |
| 992 | dev->qmult = qmult; |
| 993 | } |
| 994 | EXPORT_SYMBOL_GPL(gether_set_qmult); |
| 995 | |
| 996 | unsigned gether_get_qmult(struct net_device *net) |
| 997 | { |
| 998 | struct eth_dev *dev; |
| 999 | |
| 1000 | dev = netdev_priv(net); |
| 1001 | return dev->qmult; |
| 1002 | } |
| 1003 | EXPORT_SYMBOL_GPL(gether_get_qmult); |
| 1004 | |
| 1005 | int gether_get_ifname(struct net_device *net, char *name, int len) |
| 1006 | { |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1007 | int ret; |
| 1008 | |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 1009 | rtnl_lock(); |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1010 | ret = scnprintf(name, len, "%s\n", netdev_name(net)); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 1011 | rtnl_unlock(); |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1012 | return ret; |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 1013 | } |
| 1014 | EXPORT_SYMBOL_GPL(gether_get_ifname); |
| 1015 | |
| 1016 | /** |
| 1017 | * gether_cleanup - remove Ethernet-over-USB device |
| 1018 | * Context: may sleep |
| 1019 | * |
| 1020 | * This is called to free all resources allocated by @gether_setup(). |
| 1021 | */ |
| 1022 | void gether_cleanup(struct eth_dev *dev) |
| 1023 | { |
| 1024 | if (!dev) |
| 1025 | return; |
| 1026 | |
| 1027 | unregister_netdev(dev->net); |
| 1028 | flush_work(&dev->work); |
| 1029 | free_netdev(dev->net); |
| 1030 | } |
| 1031 | EXPORT_SYMBOL_GPL(gether_cleanup); |
| 1032 | |
| 1033 | /** |
| 1034 | * gether_connect - notify network layer that USB link is active |
| 1035 | * @link: the USB link, set up with endpoints, descriptors matching |
| 1036 | * current device speed, and any framing wrapper(s) set up. |
| 1037 | * Context: irqs blocked |
| 1038 | * |
| 1039 | * This is called to activate endpoints and let the network layer know |
| 1040 | * the connection is active ("carrier detect"). It may cause the I/O |
| 1041 | * queues to open and start letting network packets flow, but will in |
| 1042 | * any case activate the endpoints so that they respond properly to the |
| 1043 | * USB host. |
| 1044 | * |
| 1045 | * Verify net_device pointer returned using IS_ERR(). If it doesn't |
| 1046 | * indicate some error code (negative errno), ep->driver_data values |
| 1047 | * have been overwritten. |
| 1048 | */ |
| 1049 | struct net_device *gether_connect(struct gether *link) |
| 1050 | { |
| 1051 | struct eth_dev *dev = link->ioport; |
| 1052 | int result = 0; |
| 1053 | |
| 1054 | if (!dev) |
| 1055 | return ERR_PTR(-EINVAL); |
| 1056 | |
| 1057 | link->in_ep->driver_data = dev; |
| 1058 | result = usb_ep_enable(link->in_ep); |
| 1059 | if (result != 0) { |
| 1060 | DBG(dev, "enable %s --> %d\n", |
| 1061 | link->in_ep->name, result); |
| 1062 | goto fail0; |
| 1063 | } |
| 1064 | |
| 1065 | link->out_ep->driver_data = dev; |
| 1066 | result = usb_ep_enable(link->out_ep); |
| 1067 | if (result != 0) { |
| 1068 | DBG(dev, "enable %s --> %d\n", |
| 1069 | link->out_ep->name, result); |
| 1070 | goto fail1; |
| 1071 | } |
| 1072 | |
| 1073 | if (result == 0) |
| 1074 | result = alloc_requests(dev, link, qlen(dev->gadget, |
| 1075 | dev->qmult)); |
| 1076 | |
| 1077 | if (result == 0) { |
| 1078 | dev->zlp = link->is_zlp_ok; |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1079 | dev->no_skb_reserve = gadget_avoids_skb_reserve(dev->gadget); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 1080 | DBG(dev, "qlen %d\n", qlen(dev->gadget, dev->qmult)); |
| 1081 | |
| 1082 | dev->header_len = link->header_len; |
| 1083 | dev->unwrap = link->unwrap; |
| 1084 | dev->wrap = link->wrap; |
| 1085 | |
| 1086 | spin_lock(&dev->lock); |
| 1087 | dev->port_usb = link; |
| 1088 | if (netif_running(dev->net)) { |
| 1089 | if (link->open) |
| 1090 | link->open(link); |
| 1091 | } else { |
| 1092 | if (link->close) |
| 1093 | link->close(link); |
| 1094 | } |
| 1095 | spin_unlock(&dev->lock); |
| 1096 | |
| 1097 | netif_carrier_on(dev->net); |
| 1098 | if (netif_running(dev->net)) |
| 1099 | eth_start(dev, GFP_ATOMIC); |
| 1100 | |
| 1101 | /* on error, disable any endpoints */ |
| 1102 | } else { |
| 1103 | (void) usb_ep_disable(link->out_ep); |
| 1104 | fail1: |
| 1105 | (void) usb_ep_disable(link->in_ep); |
| 1106 | } |
| 1107 | fail0: |
| 1108 | /* caller is responsible for cleanup on error */ |
| 1109 | if (result < 0) |
| 1110 | return ERR_PTR(result); |
| 1111 | return dev->net; |
| 1112 | } |
| 1113 | EXPORT_SYMBOL_GPL(gether_connect); |
| 1114 | |
| 1115 | /** |
| 1116 | * gether_disconnect - notify network layer that USB link is inactive |
| 1117 | * @link: the USB link, on which gether_connect() was called |
| 1118 | * Context: irqs blocked |
| 1119 | * |
| 1120 | * This is called to deactivate endpoints and let the network layer know |
| 1121 | * the connection went inactive ("no carrier"). |
| 1122 | * |
| 1123 | * On return, the state is as if gether_connect() had never been called. |
| 1124 | * The endpoints are inactive, and accordingly without active USB I/O. |
| 1125 | * Pointers to endpoint descriptors and endpoint private data are nulled. |
| 1126 | */ |
| 1127 | void gether_disconnect(struct gether *link) |
| 1128 | { |
| 1129 | struct eth_dev *dev = link->ioport; |
| 1130 | struct usb_request *req; |
| 1131 | |
| 1132 | WARN_ON(!dev); |
| 1133 | if (!dev) |
| 1134 | return; |
| 1135 | |
| 1136 | DBG(dev, "%s\n", __func__); |
| 1137 | |
| 1138 | netif_stop_queue(dev->net); |
| 1139 | netif_carrier_off(dev->net); |
| 1140 | |
| 1141 | /* disable endpoints, forcing (synchronous) completion |
| 1142 | * of all pending i/o. then free the request objects |
| 1143 | * and forget about the endpoints. |
| 1144 | */ |
| 1145 | usb_ep_disable(link->in_ep); |
| 1146 | spin_lock(&dev->req_lock); |
| 1147 | while (!list_empty(&dev->tx_reqs)) { |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1148 | req = list_first_entry(&dev->tx_reqs, struct usb_request, list); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 1149 | list_del(&req->list); |
| 1150 | |
| 1151 | spin_unlock(&dev->req_lock); |
| 1152 | usb_ep_free_request(link->in_ep, req); |
| 1153 | spin_lock(&dev->req_lock); |
| 1154 | } |
| 1155 | spin_unlock(&dev->req_lock); |
| 1156 | link->in_ep->desc = NULL; |
| 1157 | |
| 1158 | usb_ep_disable(link->out_ep); |
| 1159 | spin_lock(&dev->req_lock); |
| 1160 | while (!list_empty(&dev->rx_reqs)) { |
Googler | 9398cc3 | 2022-12-02 17:21:52 +0800 | [diff] [blame] | 1161 | req = list_first_entry(&dev->rx_reqs, struct usb_request, list); |
Googler | af606d2 | 2022-10-26 21:40:12 -0700 | [diff] [blame] | 1162 | list_del(&req->list); |
| 1163 | |
| 1164 | spin_unlock(&dev->req_lock); |
| 1165 | usb_ep_free_request(link->out_ep, req); |
| 1166 | spin_lock(&dev->req_lock); |
| 1167 | } |
| 1168 | spin_unlock(&dev->req_lock); |
| 1169 | link->out_ep->desc = NULL; |
| 1170 | |
| 1171 | /* finish forgetting about this USB link episode */ |
| 1172 | dev->header_len = 0; |
| 1173 | dev->unwrap = NULL; |
| 1174 | dev->wrap = NULL; |
| 1175 | |
| 1176 | spin_lock(&dev->lock); |
| 1177 | dev->port_usb = NULL; |
| 1178 | spin_unlock(&dev->lock); |
| 1179 | } |
| 1180 | EXPORT_SYMBOL_GPL(gether_disconnect); |
| 1181 | |
| 1182 | MODULE_LICENSE("GPL"); |
| 1183 | MODULE_AUTHOR("David Brownell"); |