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 #include <linux/types.h>
  23 #include <linux/netdevice.h>
  24
  25 #include <brcmu_utils.h>
  26 #include <brcmu_wifi.h>
  27
  28 #include "dhd.h"
  29 #include "dhd_proto.h"
  30 #include "dhd_bus.h"
  31 #include "fwsignal.h"
  32 #include "dhd_dbg.h"
  33 #include "tracepoint.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 /**
  77  * struct brcmf_proto_bdc_header - BDC header format
  78  *
  79  * @flags: flags contain protocol and checksum info.
  80  * @priority: 802.1d priority and USB flow control info (bit 4:7).
  81  * @flags2: additional flags containing dongle interface index.
  82  * @data_offset: start of packet data. header is following by firmware signals.
  83  */
  84 struct brcmf_proto_bdc_header {
  85         u8 flags;
  86         u8 priority;
  87         u8 flags2;
  88         u8 data_offset;
  89 };
  90
  91 /*
  92  * maximum length of firmware signal data between
  93  * the BDC header and packet data in the tx path.
  94  */
  95 #define BRCMF_PROT_FW_SIGNAL_MAX_TXBYTES        12
  96
  97 #define RETRIES 2 /* # of retries to retrieve matching dcmd response */
  98 #define BUS_HEADER_LEN  (16+64)         /* Must be atleast SDPCM_RESERVE
  99                                          * (amount of header tha might be added)
 100                                          * plus any space that might be needed
 101                                          * for bus alignment padding.
 102                                          */
 103 #define ROUND_UP_MARGIN 2048    /* Biggest bus block size possible for
 104                                  * round off at the end of buffer
 105                                  * Currently is SDIO
 106                                  */
 107
 108 struct brcmf_proto {
 109         u16 reqid;
 110         u8 bus_header[BUS_HEADER_LEN];
 111         struct brcmf_proto_cdc_dcmd msg;
 112         unsigned char buf[BRCMF_DCMD_MAXLEN + ROUND_UP_MARGIN];
 113 };
 114
 115 static int brcmf_proto_cdc_msg(struct brcmf_pub *drvr)
 116 {
 117         struct brcmf_proto *prot = drvr->prot;
 118         int len = le32_to_cpu(prot->msg.len) +
 119                         sizeof(struct brcmf_proto_cdc_dcmd);
 120
 121         brcmf_dbg(CDC, "Enter\n");
 122
 123         /* NOTE : cdc->msg.len holds the desired length of the buffer to be
 124          *        returned. Only up to CDC_MAX_MSG_SIZE of this buffer area
 125          *        is actually sent to the dongle
 126          */
 127         if (len > CDC_MAX_MSG_SIZE)
 128                 len = CDC_MAX_MSG_SIZE;
 129
 130         /* Send request */
 131         return brcmf_bus_txctl(drvr->bus_if, (unsigned char *)&prot->msg, len);
 132 }
 133
 134 static int brcmf_proto_cdc_cmplt(struct brcmf_pub *drvr, u32 id, u32 len)
 135 {
 136         int ret;
 137         struct brcmf_proto *prot = drvr->prot;
 138
 139         brcmf_dbg(CDC, "Enter\n");
 140         len += sizeof(struct brcmf_proto_cdc_dcmd);
 141         do {
 142                 ret = brcmf_bus_rxctl(drvr->bus_if, (unsigned char *)&prot->msg,
 143                                       len);
 144                 if (ret < 0)
 145                         break;
 146         } while (CDC_DCMD_ID(le32_to_cpu(prot->msg.flags)) != id);
 147
 148         return ret;
 149 }
 150
 151 int
 152 brcmf_proto_cdc_query_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
 153                                void *buf, uint len)
 154 {
 155         struct brcmf_proto *prot = drvr->prot;
 156         struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
 157         void *info;
 158         int ret = 0, retries = 0;
 159         u32 id, flags;
 160
 161         brcmf_dbg(CDC, "Enter, cmd %d len %d\n", cmd, len);
 162
 163         memset(msg, 0, sizeof(struct brcmf_proto_cdc_dcmd));
 164
 165         msg->cmd = cpu_to_le32(cmd);
 166         msg->len = cpu_to_le32(len);
 167         flags = (++prot->reqid << CDC_DCMD_ID_SHIFT);
 168         flags = (flags & ~CDC_DCMD_IF_MASK) |
 169                 (ifidx << CDC_DCMD_IF_SHIFT);
 170         msg->flags = cpu_to_le32(flags);
 171
 172         if (buf)
 173                 memcpy(prot->buf, buf, len);
 174
 175         ret = brcmf_proto_cdc_msg(drvr);
 176         if (ret < 0) {
 177                 brcmf_err("brcmf_proto_cdc_msg failed w/status %d\n",
 178                           ret);
 179                 goto done;
 180         }
 181
 182 retry:
 183         /* wait for interrupt and get first fragment */
 184         ret = brcmf_proto_cdc_cmplt(drvr, prot->reqid, len);
 185         if (ret < 0)
 186                 goto done;
 187
 188         flags = le32_to_cpu(msg->flags);
 189         id = (flags & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT;
 190
 191         if ((id < prot->reqid) && (++retries < RETRIES))
 192                 goto retry;
 193         if (id != prot->reqid) {
 194                 brcmf_err("%s: unexpected request id %d (expected %d)\n",
 195                           brcmf_ifname(drvr, ifidx), id, prot->reqid);
 196                 ret = -EINVAL;
 197                 goto done;
 198         }
 199
 200         /* Check info buffer */
 201         info = (void *)&msg[1];
 202
 203         /* Copy info buffer */
 204         if (buf) {
 205                 if (ret < (int)len)
 206                         len = ret;
 207                 memcpy(buf, info, len);
 208         }
 209
 210         /* Check the ERROR flag */
 211         if (flags & CDC_DCMD_ERROR)
 212                 ret = le32_to_cpu(msg->status);
 213
 214 done:
 215         return ret;
 216 }
 217
 218 int brcmf_proto_cdc_set_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
 219                                  void *buf, uint len)
 220 {
 221         struct brcmf_proto *prot = drvr->prot;
 222         struct brcmf_proto_cdc_dcmd *msg = &prot->msg;
 223         int ret = 0;
 224         u32 flags, id;
 225
 226         brcmf_dbg(CDC, "Enter, cmd %d len %d\n", cmd, len);
 227
 228         memset(msg, 0, sizeof(struct brcmf_proto_cdc_dcmd));
 229
 230         msg->cmd = cpu_to_le32(cmd);
 231         msg->len = cpu_to_le32(len);
 232         flags = (++prot->reqid << CDC_DCMD_ID_SHIFT) | CDC_DCMD_SET;
 233         flags = (flags & ~CDC_DCMD_IF_MASK) |
 234                 (ifidx << CDC_DCMD_IF_SHIFT);
 235         msg->flags = cpu_to_le32(flags);
 236
 237         if (buf)
 238                 memcpy(prot->buf, buf, len);
 239
 240         ret = brcmf_proto_cdc_msg(drvr);
 241         if (ret < 0)
 242                 goto done;
 243
 244         ret = brcmf_proto_cdc_cmplt(drvr, prot->reqid, len);
 245         if (ret < 0)
 246                 goto done;
 247
 248         flags = le32_to_cpu(msg->flags);
 249         id = (flags & CDC_DCMD_ID_MASK) >> CDC_DCMD_ID_SHIFT;
 250
 251         if (id != prot->reqid) {
 252                 brcmf_err("%s: unexpected request id %d (expected %d)\n",
 253                           brcmf_ifname(drvr, ifidx), id, prot->reqid);
 254                 ret = -EINVAL;
 255                 goto done;
 256         }
 257
 258         /* Check the ERROR flag */
 259         if (flags & CDC_DCMD_ERROR)
 260                 ret = le32_to_cpu(msg->status);
 261
 262 done:
 263         return ret;
 264 }
 265
 266 static bool pkt_sum_needed(struct sk_buff *skb)
 267 {
 268         return skb->ip_summed == CHECKSUM_PARTIAL;
 269 }
 270
 271 static void pkt_set_sum_good(struct sk_buff *skb, bool x)
 272 {
 273         skb->ip_summed = (x ? CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
 274 }
 275
 276 void brcmf_proto_hdrpush(struct brcmf_pub *drvr, int ifidx, u8 offset,
 277                          struct sk_buff *pktbuf)
 278 {
 279         struct brcmf_proto_bdc_header *h;
 280
 281         brcmf_dbg(CDC, "Enter\n");
 282
 283         /* Push BDC header used to convey priority for buses that don't */
 284         skb_push(pktbuf, BDC_HEADER_LEN);
 285
 286         h = (struct brcmf_proto_bdc_header *)(pktbuf->data);
 287
 288         h->flags = (BDC_PROTO_VER << BDC_FLAG_VER_SHIFT);
 289         if (pkt_sum_needed(pktbuf))
 290                 h->flags |= BDC_FLAG_SUM_NEEDED;
 291
 292         h->priority = (pktbuf->priority & BDC_PRIORITY_MASK);
 293         h->flags2 = 0;
 294         h->data_offset = offset;
 295         BDC_SET_IF_IDX(h, ifidx);
 296         trace_brcmf_bdchdr(pktbuf->data);
 297 }
 298
 299 int brcmf_proto_hdrpull(struct brcmf_pub *drvr, bool do_fws, u8 *ifidx,
 300                         struct sk_buff *pktbuf)
 301 {
 302         struct brcmf_proto_bdc_header *h;
 303
 304         brcmf_dbg(CDC, "Enter\n");
 305
 306         /* Pop BDC header used to convey priority for buses that don't */
 307
 308         if (pktbuf->len <= BDC_HEADER_LEN) {
 309                 brcmf_dbg(INFO, "rx data too short (%d <= %d)\n",
 310                           pktbuf->len, BDC_HEADER_LEN);
 311                 return -EBADE;
 312         }
 313
 314         trace_brcmf_bdchdr(pktbuf->data);
 315         h = (struct brcmf_proto_bdc_header *)(pktbuf->data);
 316
 317         *ifidx = BDC_GET_IF_IDX(h);
 318         if (*ifidx >= BRCMF_MAX_IFS) {
 319                 brcmf_err("rx data ifnum out of range (%d)\n", *ifidx);
 320                 return -EBADE;
 321         }
 322         /* The ifidx is the idx to map to matching netdev/ifp. When receiving
 323          * events this is easy because it contains the bssidx which maps
 324          * 1-on-1 to the netdev/ifp. But for data frames the ifidx is rcvd.
 325          * bssidx 1 is used for p2p0 and no data can be received or
 326          * transmitted on it. Therefor bssidx is ifidx + 1 if ifidx > 0
 327          */
 328         if (*ifidx)
 329                 (*ifidx)++;
 330
 331         if (((h->flags & BDC_FLAG_VER_MASK) >> BDC_FLAG_VER_SHIFT) !=
 332             BDC_PROTO_VER) {
 333                 brcmf_err("%s: non-BDC packet received, flags 0x%x\n",
 334                           brcmf_ifname(drvr, *ifidx), h->flags);
 335                 return -EBADE;
 336         }
 337
 338         if (h->flags & BDC_FLAG_SUM_GOOD) {
 339                 brcmf_dbg(CDC, "%s: BDC rcv, good checksum, flags 0x%x\n",
 340                           brcmf_ifname(drvr, *ifidx), h->flags);
 341                 pkt_set_sum_good(pktbuf, true);
 342         }
 343
 344         pktbuf->priority = h->priority & BDC_PRIORITY_MASK;
 345
 346         skb_pull(pktbuf, BDC_HEADER_LEN);
 347         if (do_fws)
 348                 brcmf_fws_hdrpull(drvr, *ifidx, h->data_offset << 2, pktbuf);
 349         else
 350                 skb_pull(pktbuf, h->data_offset << 2);
 351
 352         if (pktbuf->len == 0)
 353                 return -ENODATA;
 354         return 0;
 355 }
 356
 357 int brcmf_proto_attach(struct brcmf_pub *drvr)
 358 {
 359         struct brcmf_proto *cdc;
 360
 361         cdc = kzalloc(sizeof(struct brcmf_proto), GFP_ATOMIC);
 362         if (!cdc)
 363                 goto fail;
 364
 365         /* ensure that the msg buf directly follows the cdc msg struct */
 366         if ((unsigned long)(&cdc->msg + 1) != (unsigned long)cdc->buf) {
 367                 brcmf_err("struct brcmf_proto is not correctly defined\n");
 368                 goto fail;
 369         }
 370
 371         drvr->prot = cdc;
 372         drvr->hdrlen += BDC_HEADER_LEN + BRCMF_PROT_FW_SIGNAL_MAX_TXBYTES;
 373         drvr->bus_if->maxctl = BRCMF_DCMD_MAXLEN +
 374                         sizeof(struct brcmf_proto_cdc_dcmd) + ROUND_UP_MARGIN;
 375         return 0;
 376
 377 fail:
 378         kfree(cdc);
 379         return -ENOMEM;
 380 }
 381
 382 /* ~NOTE~ What if another thread is waiting on the semaphore?  Holding it? */
 383 void brcmf_proto_detach(struct brcmf_pub *drvr)
 384 {
 385         kfree(drvr->prot);
 386         drvr->prot = NULL;
 387 }
 388
 389 void brcmf_proto_stop(struct brcmf_pub *drvr)
 390 {
 391         /* Nothing to do for CDC */
 392 }