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path: root/drivers/net/wireless/ath/carl9170/rx.c
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Diffstat (limited to 'drivers/net/wireless/ath/carl9170/rx.c')
-rw-r--r--drivers/net/wireless/ath/carl9170/rx.c1012
1 files changed, 1012 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..d1875f0
--- /dev/null
+++ b/drivers/net/wireless/ath/carl9170/rx.c
@@ -0,0 +1,1012 @@
+/*
+ * 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/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 = buf;
+ struct ieee80211_vif *vif;
+
+ 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:
+ case NL80211_IFTYPE_MESH_POINT:
+ 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 CPTCFG_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 /* CPTCFG_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 == NL80211_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_CTL_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 = data;
+ struct ieee80211_tim_ie *tim_ie;
+ struct ath_common *common = &ar->common;
+ u8 *tim;
+ u8 tim_len;
+ bool cam;
+
+ if (likely(!(ar->hw->conf.flags & IEEE80211_CONF_PS)))
+ return;
+
+ /* min. beacon length + FCS_LEN */
+ if (len <= 40 + FCS_LEN)
+ return;
+
+ /* check if this really is a beacon */
+ /* and only beacons from the associated BSSID, please */
+ if (!ath_is_mybeacon(common, hdr) || !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 void carl9170_ba_check(struct ar9170 *ar, void *data, unsigned int len)
+{
+ struct ieee80211_bar *bar = data;
+ struct carl9170_bar_list_entry *entry;
+ unsigned int queue;
+
+ if (likely(!ieee80211_is_back(bar->frame_control)))
+ return;
+
+ if (len <= sizeof(*bar) + FCS_LEN)
+ return;
+
+ queue = TID_TO_WME_AC(((le16_to_cpu(bar->control) &
+ IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
+ IEEE80211_BAR_CTRL_TID_INFO_SHIFT) & 7);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(entry, &ar->bar_list[queue], list) {
+ struct sk_buff *entry_skb = entry->skb;
+ struct _carl9170_tx_superframe *super = (void *)entry_skb->data;
+ struct ieee80211_bar *entry_bar = (void *)super->frame_data;
+
+#define TID_CHECK(a, b) ( \
+ ((a) & cpu_to_le16(IEEE80211_BAR_CTRL_TID_INFO_MASK)) == \
+ ((b) & cpu_to_le16(IEEE80211_BAR_CTRL_TID_INFO_MASK))) \
+
+ if (bar->start_seq_num == entry_bar->start_seq_num &&
+ TID_CHECK(bar->control, entry_bar->control) &&
+ ether_addr_equal_64bits(bar->ra, entry_bar->ta) &&
+ ether_addr_equal_64bits(bar->ta, entry_bar->ra)) {
+ struct ieee80211_tx_info *tx_info;
+
+ tx_info = IEEE80211_SKB_CB(entry_skb);
+ tx_info->flags |= IEEE80211_TX_STAT_ACK;
+
+ spin_lock_bh(&ar->bar_list_lock[queue]);
+ list_del_rcu(&entry->list);
+ spin_unlock_bh(&ar->bar_list_lock[queue]);
+ kfree_rcu(entry, head);
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+#undef TID_CHECK
+}
+
+static bool carl9170_ampdu_check(struct ar9170 *ar, u8 *buf, u8 ms,
+ struct ieee80211_rx_status *rx_status)
+{
+ __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;
+ }
+
+ rx_status->flag |= RX_FLAG_AMPDU_DETAILS | RX_FLAG_AMPDU_LAST_KNOWN;
+ rx_status->ampdu_reference = ar->ampdu_ref;
+
+ /*
+ * "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;
+}
+
+static int carl9170_handle_mpdu(struct ar9170 *ar, u8 *buf, int len,
+ struct ieee80211_rx_status *status)
+{
+ struct sk_buff *skb;
+
+ /* (driver) frame trap handler
+ *
+ * Because power-saving mode handing has to be implemented by
+ * the driver/firmware. We have to check each incoming beacon
+ * from the associated AP, if there's new data for us (either
+ * broadcast/multicast or unicast) we have to react quickly.
+ *
+ * So, if you have you want to add additional frame trap
+ * handlers, this would be the perfect place!
+ */
+
+ carl9170_ps_beacon(ar, buf, len);
+
+ carl9170_ba_check(ar, buf, len);
+
+ skb = carl9170_rx_copy_data(buf, len);
+ if (!skb)
+ return -ENOMEM;
+
+ memcpy(IEEE80211_SKB_RXCB(skb), status, sizeof(*status));
+ ieee80211_rx(ar->hw, skb);
+ return 0;
+}
+
+/*
+ * 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_rx_untie_data(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;
+ int mpdu_len;
+ u8 mac_status;
+
+ if (!IS_STARTED(ar))
+ return;
+
+ if (unlikely(len < sizeof(*mac)))
+ goto drop;
+
+ memset(&status, 0, sizeof(status));
+
+ 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:
+ ar->ampdu_ref++;
+ /* 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:
+ status.flag |= RX_FLAG_AMPDU_IS_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;
+
+ if (unlikely(carl9170_rx_mac_status(ar, head, mac, &status)))
+ goto drop;
+
+ if (!carl9170_ampdu_check(ar, buf, mac_status, &status))
+ goto drop;
+
+ if (phy)
+ carl9170_rx_phy_status(ar, phy, &status);
+ else
+ status.flag |= RX_FLAG_NO_SIGNAL_VAL;
+
+ if (carl9170_handle_mpdu(ar, buf, mpdu_len, &status))
+ goto drop;
+
+ 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;
+
+ if (carl9170_check_sequence(ar, cmd->hdr.seq))
+ 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_rx_untie_data(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 guaranteed, 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);
+}