/* ZD1211 USB-WLAN driver for Linux
   *
   * Copyright (C) 2005-2007 Ulrich Kunitz <kune@deine-taler.de>
   * Copyright (C) 2006-2007 Daniel Drake <dsd@gentoo.org>
   *
   * 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; if not, see <http://www.gnu.org/licenses/>.
   */
  
  #ifndef _ZD_MAC_H
  #define _ZD_MAC_H
  
  #include <linux/kernel.h>
  #include <net/mac80211.h>
  
  #include "zd_chip.h"
  
  struct zd_ctrlset {
  	u8     modulation;
  	__le16 tx_length;
  	u8     control;
  	/* stores only the difference to tx_length on ZD1211B */
  	__le16 packet_length;
  	__le16 current_length;
  	u8     service;
  	__le16  next_frame_length;
  } __packed;
  
  #define ZD_CS_RESERVED_SIZE	25
  
  /* The field modulation of struct zd_ctrlset controls the bit rate, the use
   * of short or long preambles in 802.11b (CCK mode) or the use of 802.11a or
   * 802.11g in OFDM mode.
   *
   * The term zd-rate is used for the combination of the modulation type flag
   * and the "pure" rate value.
   */
  #define ZD_PURE_RATE_MASK       0x0f
  #define ZD_MODULATION_TYPE_MASK 0x10
  #define ZD_RATE_MASK            (ZD_PURE_RATE_MASK|ZD_MODULATION_TYPE_MASK)
  #define ZD_PURE_RATE(modulation) ((modulation) & ZD_PURE_RATE_MASK)
  #define ZD_MODULATION_TYPE(modulation) ((modulation) & ZD_MODULATION_TYPE_MASK)
  #define ZD_RATE(modulation) ((modulation) & ZD_RATE_MASK)
  
  /* The two possible modulation types. Notify that 802.11b doesn't use the CCK
   * codeing for the 1 and 2 MBit/s rate. We stay with the term here to remain
   * consistent with uses the term at other places.
   */
  #define ZD_CCK                  0x00
  #define ZD_OFDM                 0x10
  
  /* The ZD1211 firmware uses proprietary encodings of the 802.11b (CCK) rates.
   * For OFDM the PLCP rate encodings are used. We combine these "pure" rates
   * with the modulation type flag and call the resulting values zd-rates.
   */
  #define ZD_CCK_RATE_1M          (ZD_CCK|0x00)
  #define ZD_CCK_RATE_2M          (ZD_CCK|0x01)
  #define ZD_CCK_RATE_5_5M        (ZD_CCK|0x02)
  #define ZD_CCK_RATE_11M         (ZD_CCK|0x03)
  #define ZD_OFDM_RATE_6M         (ZD_OFDM|ZD_OFDM_PLCP_RATE_6M)
  #define ZD_OFDM_RATE_9M         (ZD_OFDM|ZD_OFDM_PLCP_RATE_9M)
  #define ZD_OFDM_RATE_12M        (ZD_OFDM|ZD_OFDM_PLCP_RATE_12M)
  #define ZD_OFDM_RATE_18M        (ZD_OFDM|ZD_OFDM_PLCP_RATE_18M)
  #define ZD_OFDM_RATE_24M        (ZD_OFDM|ZD_OFDM_PLCP_RATE_24M)
  #define ZD_OFDM_RATE_36M        (ZD_OFDM|ZD_OFDM_PLCP_RATE_36M)
  #define ZD_OFDM_RATE_48M        (ZD_OFDM|ZD_OFDM_PLCP_RATE_48M)
  #define ZD_OFDM_RATE_54M        (ZD_OFDM|ZD_OFDM_PLCP_RATE_54M)
  
  /* The bit 5 of the zd_ctrlset modulation field controls the preamble in CCK
   * mode or the 802.11a/802.11g selection in OFDM mode.
   */
  #define ZD_CCK_PREA_LONG        0x00
  #define ZD_CCK_PREA_SHORT       0x20
  #define ZD_OFDM_MODE_11G        0x00
  #define ZD_OFDM_MODE_11A        0x20
  
  /* zd_ctrlset control field */
  #define ZD_CS_NEED_RANDOM_BACKOFF	0x01
  #define ZD_CS_NO_ACK			0x02
  
  #define ZD_CS_FRAME_TYPE_MASK		0x0c
  #define ZD_CS_DATA_FRAME		0x00
  #define ZD_CS_PS_POLL_FRAME		0x04
  #define ZD_CS_MANAGEMENT_FRAME		0x08
  #define ZD_CS_NO_SEQUENCE_CTL_FRAME	0x0c
  
  #define ZD_CS_WAKE_DESTINATION		0x10
  #define ZD_CS_RTS			0x20
  #define ZD_CS_ENCRYPT			0x40
  #define ZD_CS_SELF_CTS			0x80
  
  /* Incoming frames are prepended by a PLCP header */
  #define ZD_PLCP_HEADER_SIZE		5
  
  struct rx_length_info {
  	__le16 length[3];
  	__le16 tag;
  } __packed;
  
  #define RX_LENGTH_INFO_TAG		0x697e
  
  struct rx_status {
  	u8 signal_quality_cck;
  	/* rssi */
  	u8 signal_strength;
  	u8 signal_quality_ofdm;
  	u8 decryption_type;
  	u8 frame_status;
  } __packed;
  
  /* rx_status field decryption_type */
  #define ZD_RX_NO_WEP	0
  #define ZD_RX_WEP64	1
  #define ZD_RX_TKIP	2
  #define ZD_RX_AES	4
  #define ZD_RX_WEP128	5
  #define ZD_RX_WEP256	6
  
  /* rx_status field frame_status */
  #define ZD_RX_FRAME_MODULATION_MASK	0x01
  #define ZD_RX_CCK			0x00
  #define ZD_RX_OFDM			0x01
  
  #define ZD_RX_TIMEOUT_ERROR		0x02
  #define ZD_RX_FIFO_OVERRUN_ERROR	0x04
  #define ZD_RX_DECRYPTION_ERROR		0x08
  #define ZD_RX_CRC32_ERROR		0x10
  #define ZD_RX_NO_ADDR1_MATCH_ERROR	0x20
  #define ZD_RX_CRC16_ERROR		0x40
  #define ZD_RX_ERROR			0x80
  
  struct tx_retry_rate {
  	int count;	/* number of valid element in rate[] array */
  	int rate[10];	/* retry rates, described by an index in zd_rates[] */
  };
  
  struct tx_status {
  	u8 type;	/* must always be 0x01 : USB_INT_TYPE */
  	u8 id;		/* must always be 0xa0 : USB_INT_ID_RETRY_FAILED */
  	u8 rate;
  	u8 pad;
  	u8 mac[ETH_ALEN];
  	u8 retry;
  	u8 failure;
  } __packed;
  
  enum mac_flags {
  	MAC_FIXED_CHANNEL = 0x01,
  };
  
  struct housekeeping {
  	struct delayed_work link_led_work;
  };
  
  struct beacon {
  	struct delayed_work watchdog_work;
  	struct sk_buff *cur_beacon;
  	unsigned long last_update;
  	u16 interval;
  	u8 period;
  };
  
  enum zd_device_flags {
  	ZD_DEVICE_RUNNING,
  };
  
  #define ZD_MAC_STATS_BUFFER_SIZE 16
  
  #define ZD_MAC_MAX_ACK_WAITERS 50
  
  struct zd_mac {
  	struct zd_chip chip;
  	spinlock_t lock;
  	spinlock_t intr_lock;
  	struct ieee80211_hw *hw;
  	struct ieee80211_vif *vif;
  	struct housekeeping housekeeping;
  	struct beacon beacon;
  	struct work_struct set_rts_cts_work;
  	struct work_struct process_intr;
  	struct zd_mc_hash multicast_hash;
  	u8 intr_buffer[USB_MAX_EP_INT_BUFFER];
  	u8 regdomain;
  	u8 default_regdomain;
  	u8 channel;
  	int type;
  	int associated;
  	unsigned long flags;
  	struct sk_buff_head ack_wait_queue;
  	struct ieee80211_channel channels[14];
  	struct ieee80211_rate rates[12];
  	struct ieee80211_supported_band band;
  
  	/* Short preamble (used for RTS/CTS) */
  	unsigned int short_preamble:1;
  
  	/* whether to pass frames with CRC errors to stack */
  	unsigned int pass_failed_fcs:1;
  
  	/* whether to pass control frames to stack */
  	unsigned int pass_ctrl:1;
  
  	/* whether we have received a 802.11 ACK that is pending */
  	unsigned int ack_pending:1;
  
  	/* signal strength of the last 802.11 ACK received */
  	int ack_signal;
  };
  
  #define ZD_REGDOMAIN_FCC	0x10
  #define ZD_REGDOMAIN_IC		0x20
  #define ZD_REGDOMAIN_ETSI	0x30
  #define ZD_REGDOMAIN_SPAIN	0x31
  #define ZD_REGDOMAIN_FRANCE	0x32
  #define ZD_REGDOMAIN_JAPAN_2	0x40
  #define ZD_REGDOMAIN_JAPAN	0x41
  #define ZD_REGDOMAIN_JAPAN_3	0x49
  
  enum {
  	MIN_CHANNEL24 = 1,
  	MAX_CHANNEL24 = 14,
  };
  
  #define ZD_PLCP_SERVICE_LENGTH_EXTENSION 0x80
  
  struct ofdm_plcp_header {
  	u8 prefix[3];
  	__le16 service;
  } __packed;
  
  static inline u8 zd_ofdm_plcp_header_rate(const struct ofdm_plcp_header *header)
  {
  	return header->prefix[0] & 0xf;
  }
  
  /* The following defines give the encoding of the 4-bit rate field in the
   * OFDM (802.11a/802.11g) PLCP header. Notify that these values are used to
   * define the zd-rate values for OFDM.
   *
   * See the struct zd_ctrlset definition in zd_mac.h.
   */
  #define ZD_OFDM_PLCP_RATE_6M	0xb
  #define ZD_OFDM_PLCP_RATE_9M	0xf
  #define ZD_OFDM_PLCP_RATE_12M	0xa
  #define ZD_OFDM_PLCP_RATE_18M	0xe
  #define ZD_OFDM_PLCP_RATE_24M	0x9
  #define ZD_OFDM_PLCP_RATE_36M	0xd
  #define ZD_OFDM_PLCP_RATE_48M	0x8
  #define ZD_OFDM_PLCP_RATE_54M	0xc
  
  struct cck_plcp_header {
  	u8 signal;
  	u8 service;
  	__le16 length;
  	__le16 crc16;
  } __packed;
  
  static inline u8 zd_cck_plcp_header_signal(const struct cck_plcp_header *header)
  {
  	return header->signal;
  }
  
  /* These defines give the encodings of the signal field in the 802.11b PLCP
   * header. The signal field gives the bit rate of the following packet. Even
   * if technically wrong we use CCK here also for the 1 MBit/s and 2 MBit/s
   * rate to stay consistent with Zydas and our use of the term.
   *
   * Notify that these values are *not* used in the zd-rates.
   */
  #define ZD_CCK_PLCP_SIGNAL_1M	0x0a
  #define ZD_CCK_PLCP_SIGNAL_2M	0x14
  #define ZD_CCK_PLCP_SIGNAL_5M5	0x37
  #define ZD_CCK_PLCP_SIGNAL_11M	0x6e
  
  static inline struct zd_mac *zd_hw_mac(struct ieee80211_hw *hw)
  {
  	return hw->priv;
  }
  
  static inline struct zd_mac *zd_chip_to_mac(struct zd_chip *chip)
  {
  	return container_of(chip, struct zd_mac, chip);
  }
  
  static inline struct zd_mac *zd_usb_to_mac(struct zd_usb *usb)
  {
  	return zd_chip_to_mac(zd_usb_to_chip(usb));
  }
  
  static inline u8 *zd_mac_get_perm_addr(struct zd_mac *mac)
  {
  	return mac->hw->wiphy->perm_addr;
  }
  
  #define zd_mac_dev(mac) (zd_chip_dev(&(mac)->chip))
  
  struct ieee80211_hw *zd_mac_alloc_hw(struct usb_interface *intf);
  void zd_mac_clear(struct zd_mac *mac);
  
  int zd_mac_preinit_hw(struct ieee80211_hw *hw);
  int zd_mac_init_hw(struct ieee80211_hw *hw);
  
  int zd_mac_rx(struct ieee80211_hw *hw, const u8 *buffer, unsigned int length);
  void zd_mac_tx_failed(struct urb *urb);
  void zd_mac_tx_to_dev(struct sk_buff *skb, int error);
  
  int zd_op_start(struct ieee80211_hw *hw);
  void zd_op_stop(struct ieee80211_hw *hw);
  int zd_restore_settings(struct zd_mac *mac);
  
  #ifdef DEBUG
  void zd_dump_rx_status(const struct rx_status *status);
  #else
  #define zd_dump_rx_status(status)
  #endif /* DEBUG */
  
  #endif /* _ZD_MAC_H */