text: /*
   * Copyright (c) 2010 Broadcom Corporation
   *
   * Permission to use, copy, modify, and/or distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
   * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
   * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
   * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
   * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
   * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
   */
  
  /*******************************************************************************
   * Communicates with the dongle by using dcmd codes.
   * For certain dcmd codes, the dongle interprets string data from the host.
   ******************************************************************************/
  
  #include <linux/types.h>
  #include <linux/netdevice.h>
  
  #include <brcmu_utils.h>
  #include <brcmu_wifi.h>
  
  #include "core.h"
  #include "bus.h"
  #include "fwsignal.h"
  #include "debug.h"
  #include "tracepoint.h"
  #include "proto.h"
  #include "bcdc.h"
  
  struct brcmf_proto_bcdc_dcmd {
  	__le32 cmd;	/* dongle command value */
  	__le32 len;	/* lower 16: output buflen;
  			 * upper 16: input buflen (excludes header) */
  	__le32 flags;	/* flag defns given below */
  	__le32 status;	/* status code returned from the device */
  };
  
  /* BCDC flag definitions */
  #define BCDC_DCMD_ERROR		0x01		/* 1=cmd failed */
  #define BCDC_DCMD_SET		0x02		/* 0=get, 1=set cmd */
  #define BCDC_DCMD_IF_MASK	0xF000		/* I/F index */
  #define BCDC_DCMD_IF_SHIFT	12
  #define BCDC_DCMD_ID_MASK	0xFFFF0000	/* id an cmd pairing */
  #define BCDC_DCMD_ID_SHIFT	16		/* ID Mask shift bits */
  #define BCDC_DCMD_ID(flags)	\
  	(((flags) & BCDC_DCMD_ID_MASK) >> BCDC_DCMD_ID_SHIFT)
  
  /*
   * BCDC header - Broadcom specific extension of CDC.
   * Used on data packets to convey priority across USB.
   */
  #define	BCDC_HEADER_LEN		4
  #define BCDC_PROTO_VER		2	/* Protocol version */
  #define BCDC_FLAG_VER_MASK	0xf0	/* Protocol version mask */
  #define BCDC_FLAG_VER_SHIFT	4	/* Protocol version shift */
  #define BCDC_FLAG_SUM_GOOD	0x04	/* Good RX checksums */
  #define BCDC_FLAG_SUM_NEEDED	0x08	/* Dongle needs to do TX checksums */
  #define BCDC_PRIORITY_MASK	0x7
  #define BCDC_FLAG2_IF_MASK	0x0f	/* packet rx interface in APSTA */
  #define BCDC_FLAG2_IF_SHIFT	0
  
  #define BCDC_GET_IF_IDX(hdr) \
  	((int)((((hdr)->flags2) & BCDC_FLAG2_IF_MASK) >> BCDC_FLAG2_IF_SHIFT))
  #define BCDC_SET_IF_IDX(hdr, idx) \
  	((hdr)->flags2 = (((hdr)->flags2 & ~BCDC_FLAG2_IF_MASK) | \
  	((idx) << BCDC_FLAG2_IF_SHIFT)))
  
  /**
   * struct brcmf_proto_bcdc_header - BCDC header format
   *
   * @flags: flags contain protocol and checksum info.
   * @priority: 802.1d priority and USB flow control info (bit 4:7).
   * @flags2: additional flags containing dongle interface index.
   * @data_offset: start of packet data. header is following by firmware signals.
   */
  struct brcmf_proto_bcdc_header {
  	u8 flags;
  	u8 priority;
  	u8 flags2;
  	u8 data_offset;
  };
  
  /*
   * maximum length of firmware signal data between
   * the BCDC header and packet data in the tx path.
   */
  #define BRCMF_PROT_FW_SIGNAL_MAX_TXBYTES	12
  
  #define RETRIES 2 /* # of retries to retrieve matching dcmd response */
  #define BUS_HEADER_LEN	(16+64)		/* Must be atleast SDPCM_RESERVE
  					 * (amount of header tha might be added)
  					 * plus any space that might be needed
  					 * for bus alignment padding.
  					 */
  struct brcmf_bcdc {
  	u16 reqid;
  	u8 bus_header[BUS_HEADER_LEN];
  	struct brcmf_proto_bcdc_dcmd msg;
  	unsigned char buf[BRCMF_DCMD_MAXLEN];
  };
  
  
  static int
  brcmf_proto_bcdc_msg(struct brcmf_pub *drvr, int ifidx, uint cmd, void *buf,
  		     uint len, bool set)
  {
  	struct brcmf_bcdc *bcdc = (struct brcmf_bcdc *)drvr->proto->pd;
  	struct brcmf_proto_bcdc_dcmd *msg = &bcdc->msg;
  	u32 flags;
  
  	brcmf_dbg(BCDC, "Enter\n");
  
  	memset(msg, 0, sizeof(struct brcmf_proto_bcdc_dcmd));
  
  	msg->cmd = cpu_to_le32(cmd);
  	msg->len = cpu_to_le32(len);
  	flags = (++bcdc->reqid << BCDC_DCMD_ID_SHIFT);
  	if (set)
  		flags |= BCDC_DCMD_SET;
  	flags = (flags & ~BCDC_DCMD_IF_MASK) |
  		(ifidx << BCDC_DCMD_IF_SHIFT);
  	msg->flags = cpu_to_le32(flags);
  
  	if (buf)
  		memcpy(bcdc->buf, buf, len);
  
  	len += sizeof(*msg);
  	if (len > BRCMF_TX_IOCTL_MAX_MSG_SIZE)
  		len = BRCMF_TX_IOCTL_MAX_MSG_SIZE;
  
  	/* Send request */
  	return brcmf_bus_txctl(drvr->bus_if, (unsigned char *)&bcdc->msg, len);
  }
  
  static int brcmf_proto_bcdc_cmplt(struct brcmf_pub *drvr, u32 id, u32 len)
  {
  	int ret;
  	struct brcmf_bcdc *bcdc = (struct brcmf_bcdc *)drvr->proto->pd;
  
  	brcmf_dbg(BCDC, "Enter\n");
  	len += sizeof(struct brcmf_proto_bcdc_dcmd);
  	do {
  		ret = brcmf_bus_rxctl(drvr->bus_if, (unsigned char *)&bcdc->msg,
  				      len);
  		if (ret < 0)
  			break;
  	} while (BCDC_DCMD_ID(le32_to_cpu(bcdc->msg.flags)) != id);
  
  	return ret;
  }
  
  static int
  brcmf_proto_bcdc_query_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
  			    void *buf, uint len)
  {
  	struct brcmf_bcdc *bcdc = (struct brcmf_bcdc *)drvr->proto->pd;
  	struct brcmf_proto_bcdc_dcmd *msg = &bcdc->msg;
  	void *info;
  	int ret = 0, retries = 0;
  	u32 id, flags;
  
  	brcmf_dbg(BCDC, "Enter, cmd %d len %d\n", cmd, len);
  
  	ret = brcmf_proto_bcdc_msg(drvr, ifidx, cmd, buf, len, false);
  	if (ret < 0) {
  		brcmf_err("brcmf_proto_bcdc_msg failed w/status %d\n",
  			  ret);
  		goto done;
  	}
  
  retry:
  	/* wait for interrupt and get first fragment */
  	ret = brcmf_proto_bcdc_cmplt(drvr, bcdc->reqid, len);
  	if (ret < 0)
  		goto done;
  
  	flags = le32_to_cpu(msg->flags);
  	id = (flags & BCDC_DCMD_ID_MASK) >> BCDC_DCMD_ID_SHIFT;
  
  	if ((id < bcdc->reqid) && (++retries < RETRIES))
  		goto retry;
  	if (id != bcdc->reqid) {
  		brcmf_err("%s: unexpected request id %d (expected %d)\n",
  			  brcmf_ifname(brcmf_get_ifp(drvr, ifidx)), id,
  			  bcdc->reqid);
  		ret = -EINVAL;
  		goto done;
  	}
  
  	/* Check info buffer */
  	info = (void *)&msg[1];
  
  	/* Copy info buffer */
  	if (buf) {
  		if (ret < (int)len)
  			len = ret;
  		memcpy(buf, info, len);
  	}
  
  	/* Check the ERROR flag */
  	if (flags & BCDC_DCMD_ERROR)
  		ret = le32_to_cpu(msg->status);
  
  done:
  	return ret;
  }
  
  static int
  brcmf_proto_bcdc_set_dcmd(struct brcmf_pub *drvr, int ifidx, uint cmd,
  			  void *buf, uint len)
  {
  	struct brcmf_bcdc *bcdc = (struct brcmf_bcdc *)drvr->proto->pd;
  	struct brcmf_proto_bcdc_dcmd *msg = &bcdc->msg;
  	int ret = 0;
  	u32 flags, id;
  
  	brcmf_dbg(BCDC, "Enter, cmd %d len %d\n", cmd, len);
  
  	ret = brcmf_proto_bcdc_msg(drvr, ifidx, cmd, buf, len, true);
  	if (ret < 0)
  		goto done;
  
  	ret = brcmf_proto_bcdc_cmplt(drvr, bcdc->reqid, len);
  	if (ret < 0)
  		goto done;
  
  	flags = le32_to_cpu(msg->flags);
  	id = (flags & BCDC_DCMD_ID_MASK) >> BCDC_DCMD_ID_SHIFT;
  
  	if (id != bcdc->reqid) {
  		brcmf_err("%s: unexpected request id %d (expected %d)\n",
  			  brcmf_ifname(brcmf_get_ifp(drvr, ifidx)), id,
  			  bcdc->reqid);
  		ret = -EINVAL;
  		goto done;
  	}
  
  	/* Check the ERROR flag */
  	if (flags & BCDC_DCMD_ERROR)
  		ret = le32_to_cpu(msg->status);
  
  done:
  	return ret;
  }
  
  static void
  brcmf_proto_bcdc_hdrpush(struct brcmf_pub *drvr, int ifidx, u8 offset,
  			 struct sk_buff *pktbuf)
  {
  	struct brcmf_proto_bcdc_header *h;
  
  	brcmf_dbg(BCDC, "Enter\n");
  
  	/* Push BDC header used to convey priority for buses that don't */
  	skb_push(pktbuf, BCDC_HEADER_LEN);
  
  	h = (struct brcmf_proto_bcdc_header *)(pktbuf->data);
  
  	h->flags = (BCDC_PROTO_VER << BCDC_FLAG_VER_SHIFT);
  	if (pktbuf->ip_summed == CHECKSUM_PARTIAL)
  		h->flags |= BCDC_FLAG_SUM_NEEDED;
  
  	h->priority = (pktbuf->priority & BCDC_PRIORITY_MASK);
  	h->flags2 = 0;
  	h->data_offset = offset;
  	BCDC_SET_IF_IDX(h, ifidx);
  	trace_brcmf_bcdchdr(pktbuf->data);
  }
  
  static int
  brcmf_proto_bcdc_hdrpull(struct brcmf_pub *drvr, bool do_fws,
  			 struct sk_buff *pktbuf, struct brcmf_if **ifp)
  {
  	struct brcmf_proto_bcdc_header *h;
  	struct brcmf_if *tmp_if;
  
  	brcmf_dbg(BCDC, "Enter\n");
  
  	/* Pop BCDC header used to convey priority for buses that don't */
  	if (pktbuf->len <= BCDC_HEADER_LEN) {
  		brcmf_dbg(INFO, "rx data too short (%d <= %d)\n",
  			  pktbuf->len, BCDC_HEADER_LEN);
  		return -EBADE;
  	}
  
  	trace_brcmf_bcdchdr(pktbuf->data);
  	h = (struct brcmf_proto_bcdc_header *)(pktbuf->data);
  
  	tmp_if = brcmf_get_ifp(drvr, BCDC_GET_IF_IDX(h));
  	if (!tmp_if) {
  		brcmf_dbg(INFO, "no matching ifp found\n");
  		return -EBADE;
  	}
  	if (((h->flags & BCDC_FLAG_VER_MASK) >> BCDC_FLAG_VER_SHIFT) !=
  	    BCDC_PROTO_VER) {
  		brcmf_err("%s: non-BCDC packet received, flags 0x%x\n",
  			  brcmf_ifname(tmp_if), h->flags);
  		return -EBADE;
  	}
  
  	if (h->flags & BCDC_FLAG_SUM_GOOD) {
  		brcmf_dbg(BCDC, "%s: BDC rcv, good checksum, flags 0x%x\n",
  			  brcmf_ifname(tmp_if), h->flags);
  		pktbuf->ip_summed = CHECKSUM_UNNECESSARY;
  	}
  
  	pktbuf->priority = h->priority & BCDC_PRIORITY_MASK;
  
  	skb_pull(pktbuf, BCDC_HEADER_LEN);
  	if (do_fws)
  		brcmf_fws_hdrpull(tmp_if, h->data_offset << 2, pktbuf);
  	else
  		skb_pull(pktbuf, h->data_offset << 2);
  
  	if (pktbuf->len == 0)
  		return -ENODATA;
  
  	if (ifp != NULL)
  		*ifp = tmp_if;
  	return 0;
  }
  
  static int
  brcmf_proto_bcdc_txdata(struct brcmf_pub *drvr, int ifidx, u8 offset,
  			struct sk_buff *pktbuf)
  {
  	brcmf_proto_bcdc_hdrpush(drvr, ifidx, offset, pktbuf);
  	return brcmf_bus_txdata(drvr->bus_if, pktbuf);
  }
  
  static void
  brcmf_proto_bcdc_configure_addr_mode(struct brcmf_pub *drvr, int ifidx,
  				     enum proto_addr_mode addr_mode)
  {
  }
  
  static void
  brcmf_proto_bcdc_delete_peer(struct brcmf_pub *drvr, int ifidx,
  			     u8 peer[ETH_ALEN])
  {
  }
  
  static void
  brcmf_proto_bcdc_add_tdls_peer(struct brcmf_pub *drvr, int ifidx,
  			       u8 peer[ETH_ALEN])
  {
  }
  
  static void brcmf_proto_bcdc_rxreorder(struct brcmf_if *ifp,
  				       struct sk_buff *skb)
  {
  	brcmf_fws_rxreorder(ifp, skb);
  }
  
  int brcmf_proto_bcdc_attach(struct brcmf_pub *drvr)
  {
  	struct brcmf_bcdc *bcdc;
  
  	bcdc = kzalloc(sizeof(*bcdc), GFP_ATOMIC);
  	if (!bcdc)
  		goto fail;
  
  	/* ensure that the msg buf directly follows the cdc msg struct */
  	if ((unsigned long)(&bcdc->msg + 1) != (unsigned long)bcdc->buf) {
  		brcmf_err("struct brcmf_proto_bcdc is not correctly defined\n");
  		goto fail;
  	}
  
  	drvr->proto->hdrpull = brcmf_proto_bcdc_hdrpull;
  	drvr->proto->query_dcmd = brcmf_proto_bcdc_query_dcmd;
  	drvr->proto->set_dcmd = brcmf_proto_bcdc_set_dcmd;
  	drvr->proto->txdata = brcmf_proto_bcdc_txdata;
  	drvr->proto->configure_addr_mode = brcmf_proto_bcdc_configure_addr_mode;
  	drvr->proto->delete_peer = brcmf_proto_bcdc_delete_peer;
  	drvr->proto->add_tdls_peer = brcmf_proto_bcdc_add_tdls_peer;
  	drvr->proto->rxreorder = brcmf_proto_bcdc_rxreorder;
  	drvr->proto->pd = bcdc;
  
  	drvr->hdrlen += BCDC_HEADER_LEN + BRCMF_PROT_FW_SIGNAL_MAX_TXBYTES;
  	drvr->bus_if->maxctl = BRCMF_DCMD_MAXLEN +
  			sizeof(struct brcmf_proto_bcdc_dcmd);
  	return 0;
  
  fail:
  	kfree(bcdc);
  	return -ENOMEM;
  }
  
  void brcmf_proto_bcdc_detach(struct brcmf_pub *drvr)
  {
  	kfree(drvr->proto->pd);
  	drvr->proto->pd = NULL;
  }
  