diff options
Diffstat (limited to 'drivers/net/wireless/ath/carl9170/rx.c')
| -rw-r--r-- | drivers/net/wireless/ath/carl9170/rx.c | 938 |
1 files changed, 938 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/carl9170/rx.c b/drivers/net/wireless/ath/carl9170/rx.c new file mode 100644 index 0000000..939a0e9 --- /dev/null +++ b/drivers/net/wireless/ath/carl9170/rx.c @@ -0,0 +1,938 @@ +/* + * Atheros CARL9170 driver + * + * 802.11 & command trap routines + * + * Copyright 2008, Johannes Berg <johannes@sipsolutions.net> + * Copyright 2009, 2010, Christian Lamparter <chunkeey@googlemail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; see the file COPYING. If not, see + * http://www.gnu.org/licenses/. + * + * This file incorporates work covered by the following copyright and + * permission notice: + * Copyright (c) 2007-2008 Atheros Communications, Inc. + * + * 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. + */ + +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/etherdevice.h> +#include <linux/crc32.h> +#include <net/mac80211.h> +#include "carl9170.h" +#include "hw.h" +#include "cmd.h" + +static void carl9170_dbg_message(struct ar9170 *ar, const char *buf, u32 len) +{ + bool restart = false; + enum carl9170_restart_reasons reason = CARL9170_RR_NO_REASON; + + if (len > 3) { + if (memcmp(buf, CARL9170_ERR_MAGIC, 3) == 0) { + ar->fw.err_counter++; + if (ar->fw.err_counter > 3) { + restart = true; + reason = CARL9170_RR_TOO_MANY_FIRMWARE_ERRORS; + } + } + + if (memcmp(buf, CARL9170_BUG_MAGIC, 3) == 0) { + ar->fw.bug_counter++; + restart = true; + reason = CARL9170_RR_FATAL_FIRMWARE_ERROR; + } + } + + wiphy_info(ar->hw->wiphy, "FW: %.*s\n", len, buf); + + if (restart) + carl9170_restart(ar, reason); +} + +static void carl9170_handle_ps(struct ar9170 *ar, struct carl9170_rsp *rsp) +{ + u32 ps; + bool new_ps; + + ps = le32_to_cpu(rsp->psm.state); + + new_ps = (ps & CARL9170_PSM_COUNTER) != CARL9170_PSM_WAKE; + if (ar->ps.state != new_ps) { + if (!new_ps) { + ar->ps.sleep_ms = jiffies_to_msecs(jiffies - + ar->ps.last_action); + } + + ar->ps.last_action = jiffies; + + ar->ps.state = new_ps; + } +} + +static int carl9170_check_sequence(struct ar9170 *ar, unsigned int seq) +{ + if (ar->cmd_seq < -1) + return 0; + + /* + * Initialize Counter + */ + if (ar->cmd_seq < 0) + ar->cmd_seq = seq; + + /* + * The sequence is strictly monotonic increasing and it never skips! + * + * Therefore we can safely assume that whenever we received an + * unexpected sequence we have lost some valuable data. + */ + if (seq != ar->cmd_seq) { + int count; + + count = (seq - ar->cmd_seq) % ar->fw.cmd_bufs; + + wiphy_err(ar->hw->wiphy, "lost %d command responses/traps! " + "w:%d g:%d\n", count, ar->cmd_seq, seq); + + carl9170_restart(ar, CARL9170_RR_LOST_RSP); + return -EIO; + } + + ar->cmd_seq = (ar->cmd_seq + 1) % ar->fw.cmd_bufs; + return 0; +} + +static void carl9170_cmd_callback(struct ar9170 *ar, u32 len, void *buffer) +{ + /* + * Some commands may have a variable response length + * and we cannot predict the correct length in advance. + * So we only check if we provided enough space for the data. + */ + if (unlikely(ar->readlen != (len - 4))) { + dev_warn(&ar->udev->dev, "received invalid command response:" + "got %d, instead of %d\n", len - 4, ar->readlen); + print_hex_dump_bytes("carl9170 cmd:", DUMP_PREFIX_OFFSET, + ar->cmd_buf, (ar->cmd.hdr.len + 4) & 0x3f); + print_hex_dump_bytes("carl9170 rsp:", DUMP_PREFIX_OFFSET, + buffer, len); + /* + * Do not complete. The command times out, + * and we get a stack trace from there. + */ + carl9170_restart(ar, CARL9170_RR_INVALID_RSP); + } + + spin_lock(&ar->cmd_lock); + if (ar->readbuf) { + if (len >= 4) + memcpy(ar->readbuf, buffer + 4, len - 4); + + ar->readbuf = NULL; + } + complete(&ar->cmd_wait); + spin_unlock(&ar->cmd_lock); +} + +void carl9170_handle_command_response(struct ar9170 *ar, void *buf, u32 len) +{ + struct carl9170_rsp *cmd = (void *) buf; + struct ieee80211_vif *vif; + + if (carl9170_check_sequence(ar, cmd->hdr.seq)) + return; + + if ((cmd->hdr.cmd & CARL9170_RSP_FLAG) != CARL9170_RSP_FLAG) { + if (!(cmd->hdr.cmd & CARL9170_CMD_ASYNC_FLAG)) + carl9170_cmd_callback(ar, len, buf); + + return; + } + + if (unlikely(cmd->hdr.len != (len - 4))) { + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "FW: received over-/under" + "sized event %x (%d, but should be %d).\n", + cmd->hdr.cmd, cmd->hdr.len, len - 4); + + print_hex_dump_bytes("dump:", DUMP_PREFIX_NONE, + buf, len); + } + + return; + } + + /* hardware event handlers */ + switch (cmd->hdr.cmd) { + case CARL9170_RSP_PRETBTT: + /* pre-TBTT event */ + rcu_read_lock(); + vif = carl9170_get_main_vif(ar); + + if (!vif) { + rcu_read_unlock(); + break; + } + + switch (vif->type) { + case NL80211_IFTYPE_STATION: + carl9170_handle_ps(ar, cmd); + break; + + case NL80211_IFTYPE_AP: + case NL80211_IFTYPE_ADHOC: + carl9170_update_beacon(ar, true); + break; + + default: + break; + } + rcu_read_unlock(); + + break; + + + case CARL9170_RSP_TXCOMP: + /* TX status notification */ + carl9170_tx_process_status(ar, cmd); + break; + + case CARL9170_RSP_BEACON_CONFIG: + /* + * (IBSS) beacon send notification + * bytes: 04 c2 XX YY B4 B3 B2 B1 + * + * XX always 80 + * YY always 00 + * B1-B4 "should" be the number of send out beacons. + */ + break; + + case CARL9170_RSP_ATIM: + /* End of Atim Window */ + break; + + case CARL9170_RSP_WATCHDOG: + /* Watchdog Interrupt */ + carl9170_restart(ar, CARL9170_RR_WATCHDOG); + break; + + case CARL9170_RSP_TEXT: + /* firmware debug */ + carl9170_dbg_message(ar, (char *)buf + 4, len - 4); + break; + + case CARL9170_RSP_HEXDUMP: + wiphy_dbg(ar->hw->wiphy, "FW: HD %d\n", len - 4); + print_hex_dump_bytes("FW:", DUMP_PREFIX_NONE, + (char *)buf + 4, len - 4); + break; + + case CARL9170_RSP_RADAR: + if (!net_ratelimit()) + break; + + wiphy_info(ar->hw->wiphy, "FW: RADAR! Please report this " + "incident to linux-wireless@vger.kernel.org !\n"); + break; + + case CARL9170_RSP_GPIO: +#ifdef CONFIG_CARL9170_WPC + if (ar->wps.pbc) { + bool state = !!(cmd->gpio.gpio & cpu_to_le32( + AR9170_GPIO_PORT_WPS_BUTTON_PRESSED)); + + if (state != ar->wps.pbc_state) { + ar->wps.pbc_state = state; + input_report_key(ar->wps.pbc, KEY_WPS_BUTTON, + state); + input_sync(ar->wps.pbc); + } + } +#endif /* CONFIG_CARL9170_WPC */ + break; + + case CARL9170_RSP_BOOT: + complete(&ar->fw_boot_wait); + break; + + default: + wiphy_err(ar->hw->wiphy, "FW: received unhandled event %x\n", + cmd->hdr.cmd); + print_hex_dump_bytes("dump:", DUMP_PREFIX_NONE, buf, len); + break; + } +} + +static int carl9170_rx_mac_status(struct ar9170 *ar, + struct ar9170_rx_head *head, struct ar9170_rx_macstatus *mac, + struct ieee80211_rx_status *status) +{ + struct ieee80211_channel *chan; + u8 error, decrypt; + + BUILD_BUG_ON(sizeof(struct ar9170_rx_head) != 12); + BUILD_BUG_ON(sizeof(struct ar9170_rx_macstatus) != 4); + + error = mac->error; + + if (error & AR9170_RX_ERROR_WRONG_RA) { + if (!ar->sniffer_enabled) + return -EINVAL; + } + + if (error & AR9170_RX_ERROR_PLCP) { + if (!(ar->filter_state & FIF_PLCPFAIL)) + return -EINVAL; + + status->flag |= RX_FLAG_FAILED_PLCP_CRC; + } + + if (error & AR9170_RX_ERROR_FCS) { + ar->tx_fcs_errors++; + + if (!(ar->filter_state & FIF_FCSFAIL)) + return -EINVAL; + + status->flag |= RX_FLAG_FAILED_FCS_CRC; + } + + decrypt = ar9170_get_decrypt_type(mac); + if (!(decrypt & AR9170_RX_ENC_SOFTWARE) && + decrypt != AR9170_ENC_ALG_NONE) { + if ((decrypt == AR9170_ENC_ALG_TKIP) && + (error & AR9170_RX_ERROR_MMIC)) + status->flag |= RX_FLAG_MMIC_ERROR; + + status->flag |= RX_FLAG_DECRYPTED; + } + + if (error & AR9170_RX_ERROR_DECRYPT && !ar->sniffer_enabled) + return -ENODATA; + + error &= ~(AR9170_RX_ERROR_MMIC | + AR9170_RX_ERROR_FCS | + AR9170_RX_ERROR_WRONG_RA | + AR9170_RX_ERROR_DECRYPT | + AR9170_RX_ERROR_PLCP); + + /* drop any other error frames */ + if (unlikely(error)) { + /* TODO: update netdevice's RX dropped/errors statistics */ + + if (net_ratelimit()) + wiphy_dbg(ar->hw->wiphy, "received frame with " + "suspicious error code (%#x).\n", error); + + return -EINVAL; + } + + chan = ar->channel; + if (chan) { + status->band = chan->band; + status->freq = chan->center_freq; + } + + switch (mac->status & AR9170_RX_STATUS_MODULATION) { + case AR9170_RX_STATUS_MODULATION_CCK: + if (mac->status & AR9170_RX_STATUS_SHORT_PREAMBLE) + status->flag |= RX_FLAG_SHORTPRE; + switch (head->plcp[0]) { + case AR9170_RX_PHY_RATE_CCK_1M: + status->rate_idx = 0; + break; + case AR9170_RX_PHY_RATE_CCK_2M: + status->rate_idx = 1; + break; + case AR9170_RX_PHY_RATE_CCK_5M: + status->rate_idx = 2; + break; + case AR9170_RX_PHY_RATE_CCK_11M: + status->rate_idx = 3; + break; + default: + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "invalid plcp cck " + "rate (%x).\n", head->plcp[0]); + } + + return -EINVAL; + } + break; + + case AR9170_RX_STATUS_MODULATION_DUPOFDM: + case AR9170_RX_STATUS_MODULATION_OFDM: + switch (head->plcp[0] & 0xf) { + case AR9170_TXRX_PHY_RATE_OFDM_6M: + status->rate_idx = 0; + break; + case AR9170_TXRX_PHY_RATE_OFDM_9M: + status->rate_idx = 1; + break; + case AR9170_TXRX_PHY_RATE_OFDM_12M: + status->rate_idx = 2; + break; + case AR9170_TXRX_PHY_RATE_OFDM_18M: + status->rate_idx = 3; + break; + case AR9170_TXRX_PHY_RATE_OFDM_24M: + status->rate_idx = 4; + break; + case AR9170_TXRX_PHY_RATE_OFDM_36M: + status->rate_idx = 5; + break; + case AR9170_TXRX_PHY_RATE_OFDM_48M: + status->rate_idx = 6; + break; + case AR9170_TXRX_PHY_RATE_OFDM_54M: + status->rate_idx = 7; + break; + default: + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "invalid plcp ofdm " + "rate (%x).\n", head->plcp[0]); + } + + return -EINVAL; + } + if (status->band == IEEE80211_BAND_2GHZ) + status->rate_idx += 4; + break; + + case AR9170_RX_STATUS_MODULATION_HT: + if (head->plcp[3] & 0x80) + status->flag |= RX_FLAG_40MHZ; + if (head->plcp[6] & 0x80) + status->flag |= RX_FLAG_SHORT_GI; + + status->rate_idx = clamp(0, 75, head->plcp[3] & 0x7f); + status->flag |= RX_FLAG_HT; + break; + + default: + BUG(); + return -ENOSYS; + } + + return 0; +} + +static void carl9170_rx_phy_status(struct ar9170 *ar, + struct ar9170_rx_phystatus *phy, struct ieee80211_rx_status *status) +{ + int i; + + BUILD_BUG_ON(sizeof(struct ar9170_rx_phystatus) != 20); + + for (i = 0; i < 3; i++) + if (phy->rssi[i] != 0x80) + status->antenna |= BIT(i); + + /* post-process RSSI */ + for (i = 0; i < 7; i++) + if (phy->rssi[i] & 0x80) + phy->rssi[i] = ((phy->rssi[i] & 0x7f) + 1) & 0x7f; + + /* TODO: we could do something with phy_errors */ + status->signal = ar->noise[0] + phy->rssi_combined; +} + +static struct sk_buff *carl9170_rx_copy_data(u8 *buf, int len) +{ + struct sk_buff *skb; + int reserved = 0; + struct ieee80211_hdr *hdr = (void *) buf; + + if (ieee80211_is_data_qos(hdr->frame_control)) { + u8 *qc = ieee80211_get_qos_ctl(hdr); + reserved += NET_IP_ALIGN; + + if (*qc & IEEE80211_QOS_CONTROL_A_MSDU_PRESENT) + reserved += NET_IP_ALIGN; + } + + if (ieee80211_has_a4(hdr->frame_control)) + reserved += NET_IP_ALIGN; + + reserved = 32 + (reserved & NET_IP_ALIGN); + + skb = dev_alloc_skb(len + reserved); + if (likely(skb)) { + skb_reserve(skb, reserved); + memcpy(skb_put(skb, len), buf, len); + } + + return skb; +} + +static u8 *carl9170_find_ie(u8 *data, unsigned int len, u8 ie) +{ + struct ieee80211_mgmt *mgmt = (void *)data; + u8 *pos, *end; + + pos = (u8 *)mgmt->u.beacon.variable; + end = data + len; + while (pos < end) { + if (pos + 2 + pos[1] > end) + return NULL; + + if (pos[0] == ie) + return pos; + + pos += 2 + pos[1]; + } + return NULL; +} + +/* + * NOTE: + * + * The firmware is in charge of waking up the device just before + * the AP is expected to transmit the next beacon. + * + * This leaves the driver with the important task of deciding when + * to set the PHY back to bed again. + */ +static void carl9170_ps_beacon(struct ar9170 *ar, void *data, unsigned int len) +{ + struct ieee80211_hdr *hdr = (void *) data; + struct ieee80211_tim_ie *tim_ie; + u8 *tim; + u8 tim_len; + bool cam; + + if (likely(!(ar->hw->conf.flags & IEEE80211_CONF_PS))) + return; + + /* check if this really is a beacon */ + if (!ieee80211_is_beacon(hdr->frame_control)) + return; + + /* min. beacon length + FCS_LEN */ + if (len <= 40 + FCS_LEN) + return; + + /* and only beacons from the associated BSSID, please */ + if (compare_ether_addr(hdr->addr3, ar->common.curbssid) || + !ar->common.curaid) + return; + + ar->ps.last_beacon = jiffies; + + tim = carl9170_find_ie(data, len - FCS_LEN, WLAN_EID_TIM); + if (!tim) + return; + + if (tim[1] < sizeof(*tim_ie)) + return; + + tim_len = tim[1]; + tim_ie = (struct ieee80211_tim_ie *) &tim[2]; + + if (!WARN_ON_ONCE(!ar->hw->conf.ps_dtim_period)) + ar->ps.dtim_counter = (tim_ie->dtim_count - 1) % + ar->hw->conf.ps_dtim_period; + + /* Check whenever the PHY can be turned off again. */ + + /* 1. What about buffered unicast traffic for our AID? */ + cam = ieee80211_check_tim(tim_ie, tim_len, ar->common.curaid); + + /* 2. Maybe the AP wants to send multicast/broadcast data? */ + cam = !!(tim_ie->bitmap_ctrl & 0x01); + + if (!cam) { + /* back to low-power land. */ + ar->ps.off_override &= ~PS_OFF_BCN; + carl9170_ps_check(ar); + } else { + /* force CAM */ + ar->ps.off_override |= PS_OFF_BCN; + } +} + +static bool carl9170_ampdu_check(struct ar9170 *ar, u8 *buf, u8 ms) +{ + __le16 fc; + + if ((ms & AR9170_RX_STATUS_MPDU) == AR9170_RX_STATUS_MPDU_SINGLE) { + /* + * This frame is not part of an aMPDU. + * Therefore it is not subjected to any + * of the following content restrictions. + */ + return true; + } + + /* + * "802.11n - 7.4a.3 A-MPDU contents" describes in which contexts + * certain frame types can be part of an aMPDU. + * + * In order to keep the processing cost down, I opted for a + * stateless filter solely based on the frame control field. + */ + + fc = ((struct ieee80211_hdr *)buf)->frame_control; + if (ieee80211_is_data_qos(fc) && ieee80211_is_data_present(fc)) + return true; + + if (ieee80211_is_ack(fc) || ieee80211_is_back(fc) || + ieee80211_is_back_req(fc)) + return true; + + if (ieee80211_is_action(fc)) + return true; + + return false; +} + +/* + * If the frame alignment is right (or the kernel has + * CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS), and there + * is only a single MPDU in the USB frame, then we could + * submit to mac80211 the SKB directly. However, since + * there may be multiple packets in one SKB in stream + * mode, and we need to observe the proper ordering, + * this is non-trivial. + */ + +static void carl9170_handle_mpdu(struct ar9170 *ar, u8 *buf, int len) +{ + struct ar9170_rx_head *head; + struct ar9170_rx_macstatus *mac; + struct ar9170_rx_phystatus *phy = NULL; + struct ieee80211_rx_status status; + struct sk_buff *skb; + int mpdu_len; + u8 mac_status; + + if (!IS_STARTED(ar)) + return; + + if (unlikely(len < sizeof(*mac))) + goto drop; + + mpdu_len = len - sizeof(*mac); + + mac = (void *)(buf + mpdu_len); + mac_status = mac->status; + switch (mac_status & AR9170_RX_STATUS_MPDU) { + case AR9170_RX_STATUS_MPDU_FIRST: + /* Aggregated MPDUs start with an PLCP header */ + if (likely(mpdu_len >= sizeof(struct ar9170_rx_head))) { + head = (void *) buf; + + /* + * The PLCP header needs to be cached for the + * following MIDDLE + LAST A-MPDU packets. + * + * So, if you are wondering why all frames seem + * to share a common RX status information, + * then you have the answer right here... + */ + memcpy(&ar->rx_plcp, (void *) buf, + sizeof(struct ar9170_rx_head)); + + mpdu_len -= sizeof(struct ar9170_rx_head); + buf += sizeof(struct ar9170_rx_head); + + ar->rx_has_plcp = true; + } else { + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "plcp info " + "is clipped.\n"); + } + + goto drop; + } + break; + + case AR9170_RX_STATUS_MPDU_LAST: + /* + * The last frame of an A-MPDU has an extra tail + * which does contain the phy status of the whole + * aggregate. + */ + + if (likely(mpdu_len >= sizeof(struct ar9170_rx_phystatus))) { + mpdu_len -= sizeof(struct ar9170_rx_phystatus); + phy = (void *)(buf + mpdu_len); + } else { + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "frame tail " + "is clipped.\n"); + } + + goto drop; + } + + case AR9170_RX_STATUS_MPDU_MIDDLE: + /* These are just data + mac status */ + if (unlikely(!ar->rx_has_plcp)) { + if (!net_ratelimit()) + return; + + wiphy_err(ar->hw->wiphy, "rx stream does not start " + "with a first_mpdu frame tag.\n"); + + goto drop; + } + + head = &ar->rx_plcp; + break; + + case AR9170_RX_STATUS_MPDU_SINGLE: + /* single mpdu has both: plcp (head) and phy status (tail) */ + head = (void *) buf; + + mpdu_len -= sizeof(struct ar9170_rx_head); + mpdu_len -= sizeof(struct ar9170_rx_phystatus); + + buf += sizeof(struct ar9170_rx_head); + phy = (void *)(buf + mpdu_len); + break; + + default: + BUG_ON(1); + break; + } + + /* FC + DU + RA + FCS */ + if (unlikely(mpdu_len < (2 + 2 + ETH_ALEN + FCS_LEN))) + goto drop; + + memset(&status, 0, sizeof(status)); + if (unlikely(carl9170_rx_mac_status(ar, head, mac, &status))) + goto drop; + + if (!carl9170_ampdu_check(ar, buf, mac_status)) + goto drop; + + if (phy) + carl9170_rx_phy_status(ar, phy, &status); + + carl9170_ps_beacon(ar, buf, mpdu_len); + + skb = carl9170_rx_copy_data(buf, mpdu_len); + if (!skb) + goto drop; + + memcpy(IEEE80211_SKB_RXCB(skb), &status, sizeof(status)); + ieee80211_rx(ar->hw, skb); + return; + +drop: + ar->rx_dropped++; +} + +static void carl9170_rx_untie_cmds(struct ar9170 *ar, const u8 *respbuf, + const unsigned int resplen) +{ + struct carl9170_rsp *cmd; + int i = 0; + + while (i < resplen) { + cmd = (void *) &respbuf[i]; + + i += cmd->hdr.len + 4; + if (unlikely(i > resplen)) + break; + + carl9170_handle_command_response(ar, cmd, cmd->hdr.len + 4); + } + + if (unlikely(i != resplen)) { + if (!net_ratelimit()) + return; + + wiphy_err(ar->hw->wiphy, "malformed firmware trap:\n"); + print_hex_dump_bytes("rxcmd:", DUMP_PREFIX_OFFSET, + respbuf, resplen); + } +} + +static void __carl9170_rx(struct ar9170 *ar, u8 *buf, unsigned int len) +{ + unsigned int i = 0; + + /* weird thing, but this is the same in the original driver */ + while (len > 2 && i < 12 && buf[0] == 0xff && buf[1] == 0xff) { + i += 2; + len -= 2; + buf += 2; + } + + if (unlikely(len < 4)) + return; + + /* found the 6 * 0xffff marker? */ + if (i == 12) + carl9170_rx_untie_cmds(ar, buf, len); + else + carl9170_handle_mpdu(ar, buf, len); +} + +static void carl9170_rx_stream(struct ar9170 *ar, void *buf, unsigned int len) +{ + unsigned int tlen, wlen = 0, clen = 0; + struct ar9170_stream *rx_stream; + u8 *tbuf; + + tbuf = buf; + tlen = len; + + while (tlen >= 4) { + rx_stream = (void *) tbuf; + clen = le16_to_cpu(rx_stream->length); + wlen = ALIGN(clen, 4); + + /* check if this is stream has a valid tag.*/ + if (rx_stream->tag != cpu_to_le16(AR9170_RX_STREAM_TAG)) { + /* + * TODO: handle the highly unlikely event that the + * corrupted stream has the TAG at the right position. + */ + + /* check if the frame can be repaired. */ + if (!ar->rx_failover_missing) { + + /* this is not "short read". */ + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, + "missing tag!\n"); + } + + __carl9170_rx(ar, tbuf, tlen); + return; + } + + if (ar->rx_failover_missing > tlen) { + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, + "possible multi " + "stream corruption!\n"); + goto err_telluser; + } else { + goto err_silent; + } + } + + memcpy(skb_put(ar->rx_failover, tlen), tbuf, tlen); + ar->rx_failover_missing -= tlen; + + if (ar->rx_failover_missing <= 0) { + /* + * nested carl9170_rx_stream call! + * + * termination is guranteed, even when the + * combined frame also have an element with + * a bad tag. + */ + + ar->rx_failover_missing = 0; + carl9170_rx_stream(ar, ar->rx_failover->data, + ar->rx_failover->len); + + skb_reset_tail_pointer(ar->rx_failover); + skb_trim(ar->rx_failover, 0); + } + + return; + } + + /* check if stream is clipped */ + if (wlen > tlen - 4) { + if (ar->rx_failover_missing) { + /* TODO: handle double stream corruption. */ + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "double rx " + "stream corruption!\n"); + goto err_telluser; + } else { + goto err_silent; + } + } + + /* + * save incomplete data set. + * the firmware will resend the missing bits when + * the rx - descriptor comes round again. + */ + + memcpy(skb_put(ar->rx_failover, tlen), tbuf, tlen); + ar->rx_failover_missing = clen - tlen; + return; + } + __carl9170_rx(ar, rx_stream->payload, clen); + + tbuf += wlen + 4; + tlen -= wlen + 4; + } + + if (tlen) { + if (net_ratelimit()) { + wiphy_err(ar->hw->wiphy, "%d bytes of unprocessed " + "data left in rx stream!\n", tlen); + } + + goto err_telluser; + } + + return; + +err_telluser: + wiphy_err(ar->hw->wiphy, "damaged RX stream data [want:%d, " + "data:%d, rx:%d, pending:%d ]\n", clen, wlen, tlen, + ar->rx_failover_missing); + + if (ar->rx_failover_missing) + print_hex_dump_bytes("rxbuf:", DUMP_PREFIX_OFFSET, + ar->rx_failover->data, + ar->rx_failover->len); + + print_hex_dump_bytes("stream:", DUMP_PREFIX_OFFSET, + buf, len); + + wiphy_err(ar->hw->wiphy, "please check your hardware and cables, if " + "you see this message frequently.\n"); + +err_silent: + if (ar->rx_failover_missing) { + skb_reset_tail_pointer(ar->rx_failover); + skb_trim(ar->rx_failover, 0); + ar->rx_failover_missing = 0; + } +} + +void carl9170_rx(struct ar9170 *ar, void *buf, unsigned int len) +{ + if (ar->fw.rx_stream) + carl9170_rx_stream(ar, buf, len); + else + __carl9170_rx(ar, buf, len); +} |
