drivers/net/wireless/brcm80211/brcmfmac/dhd_cdc.c

   1 /*
   2  * Copyright (c) 2010 Broadcom Corporation
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
  11  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  13  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  14  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 /*******************************************************************************
  18  * Communicates with the dongle by using dcmd codes.
  19  * For certain dcmd codes, the dongle interprets string data from the host.
  20  ******************************************************************************/
  21
  22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24 #include <linux/types.h>
  25 #include <linux/netdevice.h>
  26
  27 #include <brcmu_utils.h>
  28 #include <brcmu_wifi.h>
  29
  30 #include "dhd.h"
  31 #include "dhd_proto.h"
  32 #include "dhd_bus.h"
  33 #include "dhd_dbg.h"
  34
  35 struct brcmf_proto_cdc_dcmd {
  36         __le32 cmd;     /* dongle command value */
  37         __le32 len;     /* lower 16: output buflen;
  38                          * upper 16: input buflen (excludes header) */
  39         __le32 flags;   /* flag defns given below */
  40         __le32 status;  /* status code returned from the device */
  41 };
  42
  43 /* Max valid buffer size that can be sent to the dongle */
  44 #define CDC_MAX_MSG_SIZE        (ETH_FRAME_LEN+ETH_FCS_LEN)
  45
  46 /* CDC flag definitions */
  47 #define CDC_DCMD_ERROR          0x01    /* 1=cmd failed */
  48 #define CDC_DCMD_SET            0x02    /* 0=get, 1=set cmd */
  49 #define CDC_DCMD_IF_MASK        0xF000          /* I/F index */
  50 #define CDC_DCMD_IF_SHIFT       12
  51 #define CDC_DCMD_ID_MASK        0xFFFF0000      /* id an cmd pairing */
  52 #define CDC_DCMD_ID_SHIFT       16              /* ID Mask shift bits */
  53 #define CDC_DCMD_ID(flags)      \
  54         (((flags) & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT)
  55
  56 /*
  57  * BDC header - Broadcom specific extension of CDC.
  58  * Used on data packets to convey priority across USB.
  59  */
  60 #define BDC_HEADER_LEN          4
  61 #define BDC_PROTO_VER           2       /* Protocol version */
  62 #define BDC_FLAG_VER_MASK       0xf0    /* Protocol version mask */
  63 #define BDC_FLAG_VER_SHIFT      4       /* Protocol version shift */
  64 #define BDC_FLAG_SUM_GOOD       0x04    /* Good RX checksums */
  65 #define BDC_FLAG_SUM_NEEDED     0x08    /* Dongle needs to do TX checksums */
  66 #define BDC_PRIORITY_MASK       0x7
  67 #define BDC_FLAG2_IF_MASK       0x0f    /* packet rx interface in APSTA */
  68 #define BDC_FLAG2_IF_SHIFT      0
  69
  70 #define BDC_GET_IF_IDX(hdr) \
  71         ((int)((((hdr)->flags2) & BDC_FLAG2_IF_MASK) >> BDC_FLAG2_IF_SHIFT))
  72 #define BDC_SET_IF_IDX(hdr, idx) \
  73         ((hdr)->flags2 = (((hdr)->flags2 & ~BDC_FLAG2_IF_MASK) | \
  74         ((idx) << BDC_FLAG2_IF_SHIFT)))
  75
  76 struct brcmf_proto_bdc_header {
  77         u8 flags;
  78         u8 priority;    /* 802.1d Priority, 4:7 flow control info for usb */
  79         u8 flags2;
  80         u8 data_offset;
  81 };
  82
  83
  84 #define RETRIES 2 /* # of retries to retrieve matching dcmd response */
  85 #define BUS_HEADER_LEN  (16+64)         /* Must be atleast SDPCM_RESERVE
  86                                          * (amount of header tha might be added)
  87                                          * plus any space that might be needed
  88                                          * for bus alignment padding.
  89                                          */
  90 #define ROUND_UP_MARGIN 2048    /* Biggest bus block size possible for
  91                                  * round off at the end of buffer
  92                                  * Currently is SDIO
  93                                  */
  94
  95 struct brcmf_proto {
  96         u16 reqid;
  97         u8 pending;
  98         u32 lastcmd;
  99         u8 bus_header[BUS_HEADER_LEN];
 100         struct brcmf_proto_cdc_dcmd msg;
 101         unsigned char buf[BRCMF_DCMD_MAXLEN + ROUND_UP_MARGIN];
 102 };
 103
 104 static int brcmf_proto_cdc_msg(struct brcmf_pub *drvr)
 105 {
 106         struct brcmf_proto *prot = drvr->prot;
 107         int len = le32_to_cpu(prot->msg.len) +
 108                         sizeof(struct brcmf_proto_cdc_dcmd);
 109
 110         brcmf_dbg(TRACE, "Enter\n");
 111
 112         /* NOTE : cdc->msg.len holds the desired length of the buffer to be
 113          *        returned. Only up to CDC_MAX_MSG_SIZE of this buffer area
 114          *        is actually sent to the dongle
 115          */
 116         if (len > CDC_MAX_MSG_SIZE)
 117                 len = CDC_MAX_MSG_SIZE;
 118
 119         /* Send request */
 120         return brcmf_bus_txctl(drvr->bus_if, (unsigned char *)&prot->msg, len);
 121 }
 122
 123 static int brcmf_proto_cdc_cmplt(struct brcmf_pub *drvr, u32 id, u32 len)
 124 {
 125         int ret;
 126         struct brcmf_proto *prot = drvr->prot;
 127
 128         brcmf_dbg(TRACE, "Enter\n");
 129         len += sizeof(struct brcmf_proto_cdc_dcmd);
 130         do {
 131                 ret = brcmf_bus_rxctl(drvr->bus_if, (unsigned char *)&prot->msg,
 132                                       len);
 133                 if (ret < 0)
 134                         break;
 135         } while (CDC_DCMD_ID(le32_to_cpu(prot->msg.flags)) != id);
 136
 137         return ret;
 138 }
 139
 140 int
 141 brcmf_proto_cdc_query_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
 142                                void *buf, uint len)
 143 {
 144         struct brcmf_proto *prot = drvr->prot;
 145         struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
 146         void *info;
 147         int ret = 0, retries = 0;
 148         u32 id, flags;
 149
 150         brcmf_dbg(TRACE, "Enter\n");
 151         brcmf_dbg(CTL, "cmd %d len %d\n", cmd, len);
 152
 153         /* Respond "bcmerror" and "bcmerrorstr" with local cache */
 154         if (cmd == BRCMF_C_GET_VAR && buf) {
 155                 if (!strcmp((char *)buf, "bcmerrorstr")) {
 156                         strncpy((char *)buf, "bcm_error",
 157                                 BCME_STRLEN);
 158                         goto done;
 159                 } else if (!strcmp((char *)buf, "bcmerror")) {
 160                         *(int *)buf = drvr->dongle_error;
 161                         goto done;
 162                 }
 163         }
 164
 165         memset(msg, 0, sizeof(struct brcmf_proto_cdc_dcmd));
 166
 167         msg->cmd = cpu_to_le32(cmd);
 168         msg->len = cpu_to_le32(len);
 169         flags = (++prot->reqid << CDC_DCMD_ID_SHIFT);
 170         flags = (flags & ~CDC_DCMD_IF_MASK) |
 171                 (ifidx << CDC_DCMD_IF_SHIFT);
 172         msg->flags = cpu_to_le32(flags);
 173
 174         if (buf)
 175                 memcpy(prot->buf, buf, len);
 176
 177         ret = brcmf_proto_cdc_msg(drvr);
 178         if (ret < 0) {
 179                 brcmf_err("brcmf_proto_cdc_msg failed w/status %d\n",
 180                           ret);
 181                 goto done;
 182         }
 183
 184 retry:
 185         /* wait for interrupt and get first fragment */
 186         ret = brcmf_proto_cdc_cmplt(drvr, prot->reqid, len);
 187         if (ret < 0)
 188                 goto done;
 189
 190         flags = le32_to_cpu(msg->flags);
 191         id = (flags & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT;
 192
 193         if ((id < prot->reqid) && (++retries < RETRIES))
 194                 goto retry;
 195         if (id != prot->reqid) {
 196                 brcmf_err("%s: unexpected request id %d (expected %d)\n",
 197                           brcmf_ifname(drvr, ifidx), id, prot->reqid);
 198                 ret = -EINVAL;
 199                 goto done;
 200         }
 201
 202         /* Check info buffer */
 203         info = (void *)&msg[1];
 204
 205         /* Copy info buffer */
 206         if (buf) {
 207                 if (ret < (int)len)
 208                         len = ret;
 209                 memcpy(buf, info, len);
 210         }
 211
 212         /* Check the ERROR flag */
 213         if (flags & CDC_DCMD_ERROR) {
 214                 ret = le32_to_cpu(msg->status);
 215                 /* Cache error from dongle */
 216                 drvr->dongle_error = ret;
 217         }
 218
 219 done:
 220         return ret;
 221 }
 222
 223 int brcmf_proto_cdc_set_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
 224                                  void *buf, uint len)
 225 {
 226         struct brcmf_proto *prot = drvr->prot;
 227         struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
 228         int ret = 0;
 229         u32 flags, id;
 230
 231         brcmf_dbg(TRACE, "Enter\n");
 232         brcmf_dbg(CTL, "cmd %d len %d\n", cmd, len);
 233
 234         memset(msg, 0, sizeof(struct brcmf_proto_cdc_dcmd));
 235
 236         msg->cmd = cpu_to_le32(cmd);
 237         msg->len = cpu_to_le32(len);
 238         flags = (++prot->reqid << CDC_DCMD_ID_SHIFT) | CDC_DCMD_SET;
 239         flags = (flags & ~CDC_DCMD_IF_MASK) |
 240                 (ifidx << CDC_DCMD_IF_SHIFT);
 241         msg->flags = cpu_to_le32(flags);
 242
 243         if (buf)
 244                 memcpy(prot->buf, buf, len);
 245
 246         ret = brcmf_proto_cdc_msg(drvr);
 247         if (ret < 0)
 248                 goto done;
 249
 250         ret = brcmf_proto_cdc_cmplt(drvr, prot->reqid, len);
 251         if (ret < 0)
 252                 goto done;
 253
 254         flags = le32_to_cpu(msg->flags);
 255         id = (flags & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT;
 256
 257         if (id != prot->reqid) {
 258                 brcmf_err("%s: unexpected request id %d (expected %d)\n",
 259                           brcmf_ifname(drvr, ifidx), id, prot->reqid);
 260                 ret = -EINVAL;
 261                 goto done;
 262         }
 263
 264         /* Check the ERROR flag */
 265         if (flags & CDC_DCMD_ERROR) {
 266                 ret = le32_to_cpu(msg->status);
 267                 /* Cache error from dongle */
 268                 drvr->dongle_error = ret;
 269         }
 270
 271 done:
 272         return ret;
 273 }
 274
 275 static bool pkt_sum_needed(struct sk_buff *skb)
 276 {
 277         return skb->ip_summed == CHECKSUM_PARTIAL;
 278 }
 279
 280 static void pkt_set_sum_good(struct sk_buff *skb, bool x)
 281 {
 282         skb->ip_summed = (x ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
 283 }
 284
 285 void brcmf_proto_hdrpush(struct brcmf_pub *drvr, int ifidx,
 286                          struct sk_buff *pktbuf)
 287 {
 288         struct brcmf_proto_bdc_header *h;
 289
 290         brcmf_dbg(TRACE, "Enter\n");
 291
 292         /* Push BDC header used to convey priority for buses that don't */
 293
 294         skb_push(pktbuf, BDC_HEADER_LEN);
 295
 296         h = (struct brcmf_proto_bdc_header *)(pktbuf->data);
 297
 298         h->flags = (BDC_PROTO_VER << BDC_FLAG_VER_SHIFT);
 299         if (pkt_sum_needed(pktbuf))
 300                 h->flags |= BDC_FLAG_SUM_NEEDED;
 301
 302         h->priority = (pktbuf->priority & BDC_PRIORITY_MASK);
 303         h->flags2 = 0;
 304         h->data_offset = 0;
 305         BDC_SET_IF_IDX(h, ifidx);
 306 }
 307
 308 int brcmf_proto_hdrpull(struct device *dev, int *ifidx,
 309                         struct sk_buff *pktbuf)
 310 {
 311         struct brcmf_proto_bdc_header *h;
 312         struct brcmf_bus *bus_if = dev_get_drvdata(dev);
 313         struct brcmf_pub *drvr = bus_if->drvr;
 314
 315         brcmf_dbg(TRACE, "Enter\n");
 316
 317         /* Pop BDC header used to convey priority for buses that don't */
 318
 319         if (pktbuf->len < BDC_HEADER_LEN) {
 320                 brcmf_err("rx data too short (%d < %d)\n",
 321                           pktbuf->len, BDC_HEADER_LEN);
 322                 return -EBADE;
 323         }
 324
 325         h = (struct brcmf_proto_bdc_header *)(pktbuf->data);
 326
 327         *ifidx = BDC_GET_IF_IDX(h);
 328         if (*ifidx >= BRCMF_MAX_IFS) {
 329                 brcmf_err("rx data ifnum out of range (%d)\n", *ifidx);
 330                 return -EBADE;
 331         }
 332
 333         if (((h->flags & BDC_FLAG_VER_MASK) >> BDC_FLAG_VER_SHIFT) !=
 334             BDC_PROTO_VER) {
 335                 brcmf_err("%s: non-BDC packet received, flags 0x%x\n",
 336                           brcmf_ifname(drvr, *ifidx), h->flags);
 337                 return -EBADE;
 338         }
 339
 340         if (h->flags & BDC_FLAG_SUM_GOOD) {
 341                 brcmf_dbg(INFO, "%s: BDC packet received with good rx-csum, flags 0x%x\n",
 342                           brcmf_ifname(drvr, *ifidx), h->flags);
 343                 pkt_set_sum_good(pktbuf, true);
 344         }
 345
 346         pktbuf->priority = h->priority & BDC_PRIORITY_MASK;
 347
 348         skb_pull(pktbuf, BDC_HEADER_LEN);
 349         skb_pull(pktbuf, h->data_offset << 2);
 350
 351         return 0;
 352 }
 353
 354 int brcmf_proto_attach(struct brcmf_pub *drvr)
 355 {
 356         struct brcmf_proto *cdc;
 357
 358         cdc = kzalloc(sizeof(struct brcmf_proto), GFP_ATOMIC);
 359         if (!cdc)
 360                 goto fail;
 361
 362         /* ensure that the msg buf directly follows the cdc msg struct */
 363         if ((unsigned long)(&cdc->msg + 1) != (unsigned long)cdc->buf) {
 364                 brcmf_err("struct brcmf_proto is not correctly defined\n");
 365                 goto fail;
 366         }
 367
 368         drvr->prot = cdc;
 369         drvr->hdrlen += BDC_HEADER_LEN;
 370         drvr->bus_if->maxctl = BRCMF_DCMD_MAXLEN +
 371                         sizeof(struct brcmf_proto_cdc_dcmd) + ROUND_UP_MARGIN;
 372         return 0;
 373
 374 fail:
 375         kfree(cdc);
 376         return -ENOMEM;
 377 }
 378
 379 /* ~NOTE~ What if another thread is waiting on the semaphore?  Holding it? */
 380 void brcmf_proto_detach(struct brcmf_pub *drvr)
 381 {
 382         kfree(drvr->prot);
 383         drvr->prot = NULL;
 384 }
 385
 386 void brcmf_proto_stop(struct brcmf_pub *drvr)
 387 {
 388         /* Nothing to do for CDC */
 389 }