xtensa: support DMA buffers in high memory

[cris-mirror.git] / drivers / net / wireless / ralink / rt2x00 / rt2x00.h

/*
        Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
        Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
        Copyright (C) 2004 - 2009 Gertjan van Wingerde <gwingerde@gmail.com>
        <http://rt2x00.serialmonkey.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; if not, see <http://www.gnu.org/licenses/>.
 */

/*
        Module: rt2x00
        Abstract: rt2x00 global information.
 */

#ifndef RT2X00_H
#define RT2X00_H

#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/skbuff.h>
#include <linux/workqueue.h>
#include <linux/firmware.h>
#include <linux/leds.h>
#include <linux/mutex.h>
#include <linux/etherdevice.h>
#include <linux/input-polldev.h>
#include <linux/kfifo.h>
#include <linux/hrtimer.h>
#include <linux/average.h>
#include <linux/usb.h>
#include <linux/clk.h>

#include <net/mac80211.h>

#include "rt2x00debug.h"
#include "rt2x00dump.h"
#include "rt2x00leds.h"
#include "rt2x00reg.h"
#include "rt2x00queue.h"

/*
 * Module information.
 */
#define DRV_VERSION     "2.3.0"
#define DRV_PROJECT     "http://rt2x00.serialmonkey.com"

/* Debug definitions.
 * Debug output has to be enabled during compile time.
 */
#ifdef CONFIG_RT2X00_DEBUG
#define DEBUG
#endif /* CONFIG_RT2X00_DEBUG */

/* Utility printing macros
 * rt2x00_probe_err is for messages when rt2x00_dev is uninitialized
 */
#define rt2x00_probe_err(fmt, ...)                                      \
        printk(KERN_ERR KBUILD_MODNAME ": %s: Error - " fmt,            \
               __func__, ##__VA_ARGS__)
#define rt2x00_err(dev, fmt, ...)                                       \
        wiphy_err((dev)->hw->wiphy, "%s: Error - " fmt,                 \
                  __func__, ##__VA_ARGS__)
#define rt2x00_warn(dev, fmt, ...)                                      \
        wiphy_warn((dev)->hw->wiphy, "%s: Warning - " fmt,              \
                   __func__, ##__VA_ARGS__)
#define rt2x00_info(dev, fmt, ...)                                      \
        wiphy_info((dev)->hw->wiphy, "%s: Info - " fmt,                 \
                   __func__, ##__VA_ARGS__)

/* Various debug levels */
#define rt2x00_dbg(dev, fmt, ...)                                       \
        wiphy_dbg((dev)->hw->wiphy, "%s: Debug - " fmt,                 \
                  __func__, ##__VA_ARGS__)
#define rt2x00_eeprom_dbg(dev, fmt, ...)                                \
        wiphy_dbg((dev)->hw->wiphy, "%s: EEPROM recovery - " fmt,       \
                  __func__, ##__VA_ARGS__)

/*
 * Duration calculations
 * The rate variable passed is: 100kbs.
 * To convert from bytes to bits we multiply size with 8,
 * then the size is multiplied with 10 to make the
 * real rate -> rate argument correction.
 */
#define GET_DURATION(__size, __rate)    (((__size) * 8 * 10) / (__rate))
#define GET_DURATION_RES(__size, __rate)(((__size) * 8 * 10) % (__rate))

/*
 * Determine the number of L2 padding bytes required between the header and
 * the payload.
 */
#define L2PAD_SIZE(__hdrlen)    (-(__hdrlen) & 3)

/*
 * Determine the alignment requirement,
 * to make sure the 802.11 payload is padded to a 4-byte boundrary
 * we must determine the address of the payload and calculate the
 * amount of bytes needed to move the data.
 */
#define ALIGN_SIZE(__skb, __header) \
        (((unsigned long)((__skb)->data + (__header))) & 3)

/*
 * Constants for extra TX headroom for alignment purposes.
 */
#define RT2X00_ALIGN_SIZE       4 /* Only whole frame needs alignment */
#define RT2X00_L2PAD_SIZE       8 /* Both header & payload need alignment */

/*
 * Standard timing and size defines.
 * These values should follow the ieee80211 specifications.
 */
#define ACK_SIZE                14
#define IEEE80211_HEADER        24
#define PLCP                    48
#define BEACON                  100
#define PREAMBLE                144
#define SHORT_PREAMBLE          72
#define SLOT_TIME               20
#define SHORT_SLOT_TIME         9
#define SIFS                    10
#define PIFS                    (SIFS + SLOT_TIME)
#define SHORT_PIFS              (SIFS + SHORT_SLOT_TIME)
#define DIFS                    (PIFS + SLOT_TIME)
#define SHORT_DIFS              (SHORT_PIFS + SHORT_SLOT_TIME)
#define EIFS                    (SIFS + DIFS + \
                                  GET_DURATION(IEEE80211_HEADER + ACK_SIZE, 10))
#define SHORT_EIFS              (SIFS + SHORT_DIFS + \
                                  GET_DURATION(IEEE80211_HEADER + ACK_SIZE, 10))

enum rt2x00_chip_intf {
        RT2X00_CHIP_INTF_PCI,
        RT2X00_CHIP_INTF_PCIE,
        RT2X00_CHIP_INTF_USB,
        RT2X00_CHIP_INTF_SOC,
};

/*
 * Chipset identification
 * The chipset on the device is composed of a RT and RF chip.
 * The chipset combination is important for determining device capabilities.
 */
struct rt2x00_chip {
        u16 rt;
#define RT2460          0x2460
#define RT2560          0x2560
#define RT2570          0x2570
#define RT2661          0x2661
#define RT2573          0x2573
#define RT2860          0x2860  /* 2.4GHz */
#define RT2872          0x2872  /* WSOC */
#define RT2883          0x2883  /* WSOC */
#define RT3070          0x3070
#define RT3071          0x3071
#define RT3090          0x3090  /* 2.4GHz PCIe */
#define RT3290          0x3290
#define RT3352          0x3352  /* WSOC */
#define RT3390          0x3390
#define RT3572          0x3572
#define RT3593          0x3593
#define RT3883          0x3883  /* WSOC */
#define RT5350          0x5350  /* WSOC 2.4GHz */
#define RT5390          0x5390  /* 2.4GHz */
#define RT5392          0x5392  /* 2.4GHz */
#define RT5592          0x5592
#define RT6352          0x6352  /* WSOC 2.4GHz */

        u16 rf;
        u16 rev;

        enum rt2x00_chip_intf intf;
};

/*
 * RF register values that belong to a particular channel.
 */
struct rf_channel {
        int channel;
        u32 rf1;
        u32 rf2;
        u32 rf3;
        u32 rf4;
};

/*
 * Channel information structure
 */
struct channel_info {
        unsigned int flags;
#define GEOGRAPHY_ALLOWED       0x00000001

        short max_power;
        short default_power1;
        short default_power2;
        short default_power3;
};

/*
 * Antenna setup values.
 */
struct antenna_setup {
        enum antenna rx;
        enum antenna tx;
        u8 rx_chain_num;
        u8 tx_chain_num;
};

/*
 * Quality statistics about the currently active link.
 */
struct link_qual {
        /*
         * Statistics required for Link tuning by driver
         * The rssi value is provided by rt2x00lib during the
         * link_tuner() callback function.
         * The false_cca field is filled during the link_stats()
         * callback function and could be used during the
         * link_tuner() callback function.
         */
        int rssi;
        int false_cca;

        /*
         * VGC levels
         * Hardware driver will tune the VGC level during each call
         * to the link_tuner() callback function. This vgc_level is
         * is determined based on the link quality statistics like
         * average RSSI and the false CCA count.
         *
         * In some cases the drivers need to differentiate between
         * the currently "desired" VGC level and the level configured
         * in the hardware. The latter is important to reduce the
         * number of BBP register reads to reduce register access
         * overhead. For this reason we store both values here.
         */
        u8 vgc_level;
        u8 vgc_level_reg;

        /*
         * Statistics required for Signal quality calculation.
         * These fields might be changed during the link_stats()
         * callback function.
         */
        int rx_success;
        int rx_failed;
        int tx_success;
        int tx_failed;
};

DECLARE_EWMA(rssi, 10, 8)

/*
 * Antenna settings about the currently active link.
 */
struct link_ant {
        /*
         * Antenna flags
         */
        unsigned int flags;
#define ANTENNA_RX_DIVERSITY    0x00000001
#define ANTENNA_TX_DIVERSITY    0x00000002
#define ANTENNA_MODE_SAMPLE     0x00000004

        /*
         * Currently active TX/RX antenna setup.
         * When software diversity is used, this will indicate
         * which antenna is actually used at this time.
         */
        struct antenna_setup active;

        /*
         * RSSI history information for the antenna.
         * Used to determine when to switch antenna
         * when using software diversity.
         */
        int rssi_history;

        /*
         * Current RSSI average of the currently active antenna.
         * Similar to the avg_rssi in the link_qual structure
         * this value is updated by using the walking average.
         */
        struct ewma_rssi rssi_ant;
};

/*
 * To optimize the quality of the link we need to store
 * the quality of received frames and periodically
 * optimize the link.
 */
struct link {
        /*
         * Link tuner counter
         * The number of times the link has been tuned
         * since the radio has been switched on.
         */
        u32 count;

        /*
         * Quality measurement values.
         */
        struct link_qual qual;

        /*
         * TX/RX antenna setup.
         */
        struct link_ant ant;

        /*
         * Currently active average RSSI value
         */
        struct ewma_rssi avg_rssi;

        /*
         * Work structure for scheduling periodic link tuning.
         */
        struct delayed_work work;

        /*
         * Work structure for scheduling periodic watchdog monitoring.
         * This work must be scheduled on the kernel workqueue, while
         * all other work structures must be queued on the mac80211
         * workqueue. This guarantees that the watchdog can schedule
         * other work structures and wait for their completion in order
         * to bring the device/driver back into the desired state.
         */
        struct delayed_work watchdog_work;

        /*
         * Work structure for scheduling periodic AGC adjustments.
         */
        struct delayed_work agc_work;

        /*
         * Work structure for scheduling periodic VCO calibration.
         */
        struct delayed_work vco_work;
};

enum rt2x00_delayed_flags {
        DELAYED_UPDATE_BEACON,
};

/*
 * Interface structure
 * Per interface configuration details, this structure
 * is allocated as the private data for ieee80211_vif.
 */
struct rt2x00_intf {
        /*
         * beacon->skb must be protected with the mutex.
         */
        struct mutex beacon_skb_mutex;

        /*
         * Entry in the beacon queue which belongs to
         * this interface. Each interface has its own
         * dedicated beacon entry.
         */
        struct queue_entry *beacon;
        bool enable_beacon;

        /*
         * Actions that needed rescheduling.
         */
        unsigned long delayed_flags;

        /*
         * Software sequence counter, this is only required
         * for hardware which doesn't support hardware
         * sequence counting.
         */
        atomic_t seqno;
};

static inline struct rt2x00_intf* vif_to_intf(struct ieee80211_vif *vif)
{
        return (struct rt2x00_intf *)vif->drv_priv;
}

/**
 * struct hw_mode_spec: Hardware specifications structure
 *
 * Details about the supported modes, rates and channels
 * of a particular chipset. This is used by rt2x00lib
 * to build the ieee80211_hw_mode array for mac80211.
 *
 * @supported_bands: Bitmask contained the supported bands (2.4GHz, 5.2GHz).
 * @supported_rates: Rate types which are supported (CCK, OFDM).
 * @num_channels: Number of supported channels. This is used as array size
 *      for @tx_power_a, @tx_power_bg and @channels.
 * @channels: Device/chipset specific channel values (See &struct rf_channel).
 * @channels_info: Additional information for channels (See &struct channel_info).
 * @ht: Driver HT Capabilities (See &ieee80211_sta_ht_cap).
 */
struct hw_mode_spec {
        unsigned int supported_bands;
#define SUPPORT_BAND_2GHZ       0x00000001
#define SUPPORT_BAND_5GHZ       0x00000002

        unsigned int supported_rates;
#define SUPPORT_RATE_CCK        0x00000001
#define SUPPORT_RATE_OFDM       0x00000002

        unsigned int num_channels;
        const struct rf_channel *channels;
        const struct channel_info *channels_info;

        struct ieee80211_sta_ht_cap ht;
};

/*
 * Configuration structure wrapper around the
 * mac80211 configuration structure.
 * When mac80211 configures the driver, rt2x00lib
 * can precalculate values which are equal for all
 * rt2x00 drivers. Those values can be stored in here.
 */
struct rt2x00lib_conf {
        struct ieee80211_conf *conf;

        struct rf_channel rf;
        struct channel_info channel;
};

/*
 * Configuration structure for erp settings.
 */
struct rt2x00lib_erp {
        int short_preamble;
        int cts_protection;

        u32 basic_rates;

        int slot_time;

        short sifs;
        short pifs;
        short difs;
        short eifs;

        u16 beacon_int;
        u16 ht_opmode;
};

/*
 * Configuration structure for hardware encryption.
 */
struct rt2x00lib_crypto {
        enum cipher cipher;

        enum set_key_cmd cmd;
        const u8 *address;

        u32 bssidx;

        u8 key[16];
        u8 tx_mic[8];
        u8 rx_mic[8];

        int wcid;
};

/*
 * Configuration structure wrapper around the
 * rt2x00 interface configuration handler.
 */
struct rt2x00intf_conf {
        /*
         * Interface type
         */
        enum nl80211_iftype type;

        /*
         * TSF sync value, this is dependent on the operation type.
         */
        enum tsf_sync sync;

        /*
         * The MAC and BSSID addresses are simple array of bytes,
         * these arrays are little endian, so when sending the addresses
         * to the drivers, copy the it into a endian-signed variable.
         *
         * Note that all devices (except rt2500usb) have 32 bits
         * register word sizes. This means that whatever variable we
         * pass _must_ be a multiple of 32 bits. Otherwise the device
         * might not accept what we are sending to it.
         * This will also make it easier for the driver to write
         * the data to the device.
         */
        __le32 mac[2];
        __le32 bssid[2];
};

/*
 * Private structure for storing STA details
 * wcid: Wireless Client ID
 */
struct rt2x00_sta {
        int wcid;
};

static inline struct rt2x00_sta* sta_to_rt2x00_sta(struct ieee80211_sta *sta)
{
        return (struct rt2x00_sta *)sta->drv_priv;
}

/*
 * rt2x00lib callback functions.
 */
struct rt2x00lib_ops {
        /*
         * Interrupt handlers.
         */
        irq_handler_t irq_handler;

        /*
         * TX status tasklet handler.
         */
        void (*txstatus_tasklet) (unsigned long data);
        void (*pretbtt_tasklet) (unsigned long data);
        void (*tbtt_tasklet) (unsigned long data);
        void (*rxdone_tasklet) (unsigned long data);
        void (*autowake_tasklet) (unsigned long data);

        /*
         * Device init handlers.
         */
        int (*probe_hw) (struct rt2x00_dev *rt2x00dev);
        char *(*get_firmware_name) (struct rt2x00_dev *rt2x00dev);
        int (*check_firmware) (struct rt2x00_dev *rt2x00dev,
                               const u8 *data, const size_t len);
        int (*load_firmware) (struct rt2x00_dev *rt2x00dev,
                              const u8 *data, const size_t len);

        /*
         * Device initialization/deinitialization handlers.
         */
        int (*initialize) (struct rt2x00_dev *rt2x00dev);
        void (*uninitialize) (struct rt2x00_dev *rt2x00dev);

        /*
         * queue initialization handlers
         */
        bool (*get_entry_state) (struct queue_entry *entry);
        void (*clear_entry) (struct queue_entry *entry);

        /*
         * Radio control handlers.
         */
        int (*set_device_state) (struct rt2x00_dev *rt2x00dev,
                                 enum dev_state state);
        int (*rfkill_poll) (struct rt2x00_dev *rt2x00dev);
        void (*link_stats) (struct rt2x00_dev *rt2x00dev,
                            struct link_qual *qual);
        void (*reset_tuner) (struct rt2x00_dev *rt2x00dev,
                             struct link_qual *qual);
        void (*link_tuner) (struct rt2x00_dev *rt2x00dev,
                            struct link_qual *qual, const u32 count);
        void (*gain_calibration) (struct rt2x00_dev *rt2x00dev);
        void (*vco_calibration) (struct rt2x00_dev *rt2x00dev);

        /*
         * Data queue handlers.
         */
        void (*watchdog) (struct rt2x00_dev *rt2x00dev);
        void (*start_queue) (struct data_queue *queue);
        void (*kick_queue) (struct data_queue *queue);
        void (*stop_queue) (struct data_queue *queue);
        void (*flush_queue) (struct data_queue *queue, bool drop);
        void (*tx_dma_done) (struct queue_entry *entry);

        /*
         * TX control handlers
         */
        void (*write_tx_desc) (struct queue_entry *entry,
                               struct txentry_desc *txdesc);
        void (*write_tx_data) (struct queue_entry *entry,
                               struct txentry_desc *txdesc);
        void (*write_beacon) (struct queue_entry *entry,
                              struct txentry_desc *txdesc);
        void (*clear_beacon) (struct queue_entry *entry);
        int (*get_tx_data_len) (struct queue_entry *entry);

        /*
         * RX control handlers
         */
        void (*fill_rxdone) (struct queue_entry *entry,
                             struct rxdone_entry_desc *rxdesc);

        /*
         * Configuration handlers.
         */
        int (*config_shared_key) (struct rt2x00_dev *rt2x00dev,
                                  struct rt2x00lib_crypto *crypto,
                                  struct ieee80211_key_conf *key);
        int (*config_pairwise_key) (struct rt2x00_dev *rt2x00dev,
                                    struct rt2x00lib_crypto *crypto,
                                    struct ieee80211_key_conf *key);
        void (*config_filter) (struct rt2x00_dev *rt2x00dev,
                               const unsigned int filter_flags);
        void (*config_intf) (struct rt2x00_dev *rt2x00dev,
                             struct rt2x00_intf *intf,
                             struct rt2x00intf_conf *conf,
                             const unsigned int flags);
#define CONFIG_UPDATE_TYPE              ( 1 << 1 )
#define CONFIG_UPDATE_MAC               ( 1 << 2 )
#define CONFIG_UPDATE_BSSID             ( 1 << 3 )

        void (*config_erp) (struct rt2x00_dev *rt2x00dev,
                            struct rt2x00lib_erp *erp,
                            u32 changed);
        void (*config_ant) (struct rt2x00_dev *rt2x00dev,
                            struct antenna_setup *ant);
        void (*config) (struct rt2x00_dev *rt2x00dev,
                        struct rt2x00lib_conf *libconf,
                        const unsigned int changed_flags);
        int (*sta_add) (struct rt2x00_dev *rt2x00dev,
                        struct ieee80211_vif *vif,
                        struct ieee80211_sta *sta);
        int (*sta_remove) (struct rt2x00_dev *rt2x00dev,
                           struct ieee80211_sta *sta);
};

/*
 * rt2x00 driver callback operation structure.
 */
struct rt2x00_ops {
        const char *name;
        const unsigned int drv_data_size;
        const unsigned int max_ap_intf;
        const unsigned int eeprom_size;
        const unsigned int rf_size;
        const unsigned int tx_queues;
        void (*queue_init)(struct data_queue *queue);
        const struct rt2x00lib_ops *lib;
        const void *drv;
        const struct ieee80211_ops *hw;
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
        const struct rt2x00debug *debugfs;
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

/*
 * rt2x00 state flags
 */
enum rt2x00_state_flags {
        /*
         * Device flags
         */
        DEVICE_STATE_PRESENT,
        DEVICE_STATE_REGISTERED_HW,
        DEVICE_STATE_INITIALIZED,
        DEVICE_STATE_STARTED,
        DEVICE_STATE_ENABLED_RADIO,
        DEVICE_STATE_SCANNING,

        /*
         * Driver configuration
         */
        CONFIG_CHANNEL_HT40,
        CONFIG_POWERSAVING,
        CONFIG_HT_DISABLED,
        CONFIG_QOS_DISABLED,
        CONFIG_MONITORING,

        /*
         * Mark we currently are sequentially reading TX_STA_FIFO register
         * FIXME: this is for only rt2800usb, should go to private data
         */
        TX_STATUS_READING,
};

/*
 * rt2x00 capability flags
 */
enum rt2x00_capability_flags {
        /*
         * Requirements
         */
        REQUIRE_FIRMWARE,
        REQUIRE_BEACON_GUARD,
        REQUIRE_ATIM_QUEUE,
        REQUIRE_DMA,
        REQUIRE_COPY_IV,
        REQUIRE_L2PAD,
        REQUIRE_TXSTATUS_FIFO,
        REQUIRE_TASKLET_CONTEXT,
        REQUIRE_SW_SEQNO,
        REQUIRE_HT_TX_DESC,
        REQUIRE_PS_AUTOWAKE,
        REQUIRE_DELAYED_RFKILL,

        /*
         * Capabilities
         */
        CAPABILITY_HW_BUTTON,
        CAPABILITY_HW_CRYPTO,
        CAPABILITY_POWER_LIMIT,
        CAPABILITY_CONTROL_FILTERS,
        CAPABILITY_CONTROL_FILTER_PSPOLL,
        CAPABILITY_PRE_TBTT_INTERRUPT,
        CAPABILITY_LINK_TUNING,
        CAPABILITY_FRAME_TYPE,
        CAPABILITY_RF_SEQUENCE,
        CAPABILITY_EXTERNAL_LNA_A,
        CAPABILITY_EXTERNAL_LNA_BG,
        CAPABILITY_DOUBLE_ANTENNA,
        CAPABILITY_BT_COEXIST,
        CAPABILITY_VCO_RECALIBRATION,
        CAPABILITY_EXTERNAL_PA_TX0,
        CAPABILITY_EXTERNAL_PA_TX1,
};

/*
 * Interface combinations
 */
enum {
        IF_COMB_AP = 0,
        NUM_IF_COMB,
};

/*
 * rt2x00 device structure.
 */
struct rt2x00_dev {
        /*
         * Device structure.
         * The structure stored in here depends on the
         * system bus (PCI or USB).
         * When accessing this variable, the rt2x00dev_{pci,usb}
         * macros should be used for correct typecasting.
         */
        struct device *dev;

        /*
         * Callback functions.
         */
        const struct rt2x00_ops *ops;

        /*
         * Driver data.
         */
        void *drv_data;

        /*
         * IEEE80211 control structure.
         */
        struct ieee80211_hw *hw;
        struct ieee80211_supported_band bands[NUM_NL80211_BANDS];
        enum nl80211_band curr_band;
        int curr_freq;

        /*
         * If enabled, the debugfs interface structures
         * required for deregistration of debugfs.
         */
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
        struct rt2x00debug_intf *debugfs_intf;
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */

        /*
         * LED structure for changing the LED status
         * by mac8011 or the kernel.
         */
#ifdef CONFIG_RT2X00_LIB_LEDS
        struct rt2x00_led led_radio;
        struct rt2x00_led led_assoc;
        struct rt2x00_led led_qual;
        u16 led_mcu_reg;
#endif /* CONFIG_RT2X00_LIB_LEDS */

        /*
         * Device state flags.
         * In these flags the current status is stored.
         * Access to these flags should occur atomically.
         */
        unsigned long flags;

        /*
         * Device capabiltiy flags.
         * In these flags the device/driver capabilities are stored.
         * Access to these flags should occur non-atomically.
         */
        unsigned long cap_flags;

        /*
         * Device information, Bus IRQ and name (PCI, SoC)
         */
        int irq;
        const char *name;

        /*
         * Chipset identification.
         */
        struct rt2x00_chip chip;

        /*
         * hw capability specifications.
         */
        struct hw_mode_spec spec;

        /*
         * This is the default TX/RX antenna setup as indicated
         * by the device's EEPROM.
         */
        struct antenna_setup default_ant;

        /*
         * Register pointers
         * csr.base: CSR base register address. (PCI)
         * csr.cache: CSR cache for usb_control_msg. (USB)
         */
        union csr {
                void __iomem *base;
                void *cache;
        } csr;

        /*
         * Mutex to protect register accesses.
         * For PCI and USB devices it protects against concurrent indirect
         * register access (BBP, RF, MCU) since accessing those
         * registers require multiple calls to the CSR registers.
         * For USB devices it also protects the csr_cache since that
         * field is used for normal CSR access and it cannot support
         * multiple callers simultaneously.
         */
        struct mutex csr_mutex;

        /*
         * Mutex to synchronize config and link tuner.
         */
        struct mutex conf_mutex;
        /*
         * Current packet filter configuration for the device.
         * This contains all currently active FIF_* flags send
         * to us by mac80211 during configure_filter().
         */
        unsigned int packet_filter;

        /*
         * Interface details:
         *  - Open ap interface count.
         *  - Open sta interface count.
         *  - Association count.
         *  - Beaconing enabled count.
         */
        unsigned int intf_ap_count;
        unsigned int intf_sta_count;
        unsigned int intf_associated;
        unsigned int intf_beaconing;

        /*
         * Interface combinations
         */
        struct ieee80211_iface_limit if_limits_ap;
        struct ieee80211_iface_combination if_combinations[NUM_IF_COMB];

        /*
         * Link quality
         */
        struct link link;

        /*
         * EEPROM data.
         */
        __le16 *eeprom;

        /*
         * Active RF register values.
         * These are stored here so we don't need
         * to read the rf registers and can directly
         * use this value instead.
         * This field should be accessed by using
         * rt2x00_rf_read() and rt2x00_rf_write().
         */
        u32 *rf;

        /*
         * LNA gain
         */
        short lna_gain;

        /*
         * Current TX power value.
         */
        u16 tx_power;

        /*
         * Current retry values.
         */
        u8 short_retry;
        u8 long_retry;

        /*
         * Rssi <-> Dbm offset
         */
        u8 rssi_offset;

        /*
         * Frequency offset.
         */
        u8 freq_offset;

        /*
         * Association id.
         */
        u16 aid;

        /*
         * Beacon interval.
         */
        u16 beacon_int;

        /**
         * Timestamp of last received beacon
         */
        unsigned long last_beacon;

        /*
         * Low level statistics which will have
         * to be kept up to date while device is running.
         */
        struct ieee80211_low_level_stats low_level_stats;

        /**
         * Work queue for all work which should not be placed
         * on the mac80211 workqueue (because of dependencies
         * between various work structures).
         */
        struct workqueue_struct *workqueue;

        /*
         * Scheduled work.
         * NOTE: intf_work will use ieee80211_iterate_active_interfaces()
         * which means it cannot be placed on the hw->workqueue
         * due to RTNL locking requirements.
         */
        struct work_struct intf_work;

        /**
         * Scheduled work for TX/RX done handling (USB devices)
         */
        struct work_struct rxdone_work;
        struct work_struct txdone_work;

        /*
         * Powersaving work
         */
        struct delayed_work autowakeup_work;
        struct work_struct sleep_work;

        /*
         * Data queue arrays for RX, TX, Beacon and ATIM.
         */
        unsigned int data_queues;
        struct data_queue *rx;
        struct data_queue *tx;
        struct data_queue *bcn;
        struct data_queue *atim;

        /*
         * Firmware image.
         */
        const struct firmware *fw;

        /*
         * FIFO for storing tx status reports between isr and tasklet.
         */
        DECLARE_KFIFO_PTR(txstatus_fifo, u32);

        /*
         * Timer to ensure tx status reports are read (rt2800usb).
         */
        struct hrtimer txstatus_timer;

        /*
         * Tasklet for processing tx status reports (rt2800pci).
         */
        struct tasklet_struct txstatus_tasklet;
        struct tasklet_struct pretbtt_tasklet;
        struct tasklet_struct tbtt_tasklet;
        struct tasklet_struct rxdone_tasklet;
        struct tasklet_struct autowake_tasklet;

        /*
         * Used for VCO periodic calibration.
         */
        int rf_channel;

        /*
         * Protect the interrupt mask register.
         */
        spinlock_t irqmask_lock;

        /*
         * List of BlockAckReq TX entries that need driver BlockAck processing.
         */
        struct list_head bar_list;
        spinlock_t bar_list_lock;

        /* Extra TX headroom required for alignment purposes. */
        unsigned int extra_tx_headroom;

        struct usb_anchor *anchor;

        /* Clock for System On Chip devices. */
        struct clk *clk;
};

struct rt2x00_bar_list_entry {
        struct list_head list;
        struct rcu_head head;

        struct queue_entry *entry;
        int block_acked;

        /* Relevant parts of the IEEE80211 BAR header */
        __u8 ra[6];
        __u8 ta[6];
        __le16 control;
        __le16 start_seq_num;
};

/*
 * Register defines.
 * Some registers require multiple attempts before success,
 * in those cases REGISTER_BUSY_COUNT attempts should be
 * taken with a REGISTER_BUSY_DELAY interval. Due to USB
 * bus delays, we do not have to loop so many times to wait
 * for valid register value on that bus.
 */
#define REGISTER_BUSY_COUNT     100
#define REGISTER_USB_BUSY_COUNT 20
#define REGISTER_BUSY_DELAY     100

/*
 * Generic RF access.
 * The RF is being accessed by word index.
 */
static inline u32 rt2x00_rf_read(struct rt2x00_dev *rt2x00dev,
                                 const unsigned int word)
{
        BUG_ON(word < 1 || word > rt2x00dev->ops->rf_size / sizeof(u32));
        return rt2x00dev->rf[word - 1];
}

static inline void rt2x00_rf_write(struct rt2x00_dev *rt2x00dev,
                                   const unsigned int word, u32 data)
{
        BUG_ON(word < 1 || word > rt2x00dev->ops->rf_size / sizeof(u32));
        rt2x00dev->rf[word - 1] = data;
}

/*
 * Generic EEPROM access. The EEPROM is being accessed by word or byte index.
 */
static inline void *rt2x00_eeprom_addr(struct rt2x00_dev *rt2x00dev,
                                       const unsigned int word)
{
        return (void *)&rt2x00dev->eeprom[word];
}

static inline u16 rt2x00_eeprom_read(struct rt2x00_dev *rt2x00dev,
                                     const unsigned int word)
{
        return le16_to_cpu(rt2x00dev->eeprom[word]);
}

static inline void rt2x00_eeprom_write(struct rt2x00_dev *rt2x00dev,
                                       const unsigned int word, u16 data)
{
        rt2x00dev->eeprom[word] = cpu_to_le16(data);
}

static inline u8 rt2x00_eeprom_byte(struct rt2x00_dev *rt2x00dev,
                                    const unsigned int byte)
{
        return *(((u8 *)rt2x00dev->eeprom) + byte);
}

/*
 * Chipset handlers
 */
static inline void rt2x00_set_chip(struct rt2x00_dev *rt2x00dev,
                                   const u16 rt, const u16 rf, const u16 rev)
{
        rt2x00dev->chip.rt = rt;
        rt2x00dev->chip.rf = rf;
        rt2x00dev->chip.rev = rev;

        rt2x00_info(rt2x00dev, "Chipset detected - rt: %04x, rf: %04x, rev: %04x\n",
                    rt2x00dev->chip.rt, rt2x00dev->chip.rf,
                    rt2x00dev->chip.rev);
}

static inline void rt2x00_set_rt(struct rt2x00_dev *rt2x00dev,
                                 const u16 rt, const u16 rev)
{
        rt2x00dev->chip.rt = rt;
        rt2x00dev->chip.rev = rev;

        rt2x00_info(rt2x00dev, "RT chipset %04x, rev %04x detected\n",
                    rt2x00dev->chip.rt, rt2x00dev->chip.rev);
}

static inline void rt2x00_set_rf(struct rt2x00_dev *rt2x00dev, const u16 rf)
{
        rt2x00dev->chip.rf = rf;

        rt2x00_info(rt2x00dev, "RF chipset %04x detected\n",
                    rt2x00dev->chip.rf);
}

static inline bool rt2x00_rt(struct rt2x00_dev *rt2x00dev, const u16 rt)
{
        return (rt2x00dev->chip.rt == rt);
}

static inline bool rt2x00_rf(struct rt2x00_dev *rt2x00dev, const u16 rf)
{
        return (rt2x00dev->chip.rf == rf);
}

static inline u16 rt2x00_rev(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00dev->chip.rev;
}

static inline bool rt2x00_rt_rev(struct rt2x00_dev *rt2x00dev,
                                 const u16 rt, const u16 rev)
{
        return (rt2x00_rt(rt2x00dev, rt) && rt2x00_rev(rt2x00dev) == rev);
}

static inline bool rt2x00_rt_rev_lt(struct rt2x00_dev *rt2x00dev,
                                    const u16 rt, const u16 rev)
{
        return (rt2x00_rt(rt2x00dev, rt) && rt2x00_rev(rt2x00dev) < rev);
}

static inline bool rt2x00_rt_rev_gte(struct rt2x00_dev *rt2x00dev,
                                     const u16 rt, const u16 rev)
{
        return (rt2x00_rt(rt2x00dev, rt) && rt2x00_rev(rt2x00dev) >= rev);
}

static inline void rt2x00_set_chip_intf(struct rt2x00_dev *rt2x00dev,
                                        enum rt2x00_chip_intf intf)
{
        rt2x00dev->chip.intf = intf;
}

static inline bool rt2x00_intf(struct rt2x00_dev *rt2x00dev,
                               enum rt2x00_chip_intf intf)
{
        return (rt2x00dev->chip.intf == intf);
}

static inline bool rt2x00_is_pci(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_intf(rt2x00dev, RT2X00_CHIP_INTF_PCI) ||
               rt2x00_intf(rt2x00dev, RT2X00_CHIP_INTF_PCIE);
}

static inline bool rt2x00_is_pcie(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_intf(rt2x00dev, RT2X00_CHIP_INTF_PCIE);
}

static inline bool rt2x00_is_usb(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_intf(rt2x00dev, RT2X00_CHIP_INTF_USB);
}

static inline bool rt2x00_is_soc(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_intf(rt2x00dev, RT2X00_CHIP_INTF_SOC);
}

/* Helpers for capability flags */

static inline bool
rt2x00_has_cap_flag(struct rt2x00_dev *rt2x00dev,
                    enum rt2x00_capability_flags cap_flag)
{
        return test_bit(cap_flag, &rt2x00dev->cap_flags);
}

static inline bool
rt2x00_has_cap_hw_crypto(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_HW_CRYPTO);
}

static inline bool
rt2x00_has_cap_power_limit(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_POWER_LIMIT);
}

static inline bool
rt2x00_has_cap_control_filters(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_CONTROL_FILTERS);
}

static inline bool
rt2x00_has_cap_control_filter_pspoll(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_CONTROL_FILTER_PSPOLL);
}

static inline bool
rt2x00_has_cap_pre_tbtt_interrupt(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_PRE_TBTT_INTERRUPT);
}

static inline bool
rt2x00_has_cap_link_tuning(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_LINK_TUNING);
}

static inline bool
rt2x00_has_cap_frame_type(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_FRAME_TYPE);
}

static inline bool
rt2x00_has_cap_rf_sequence(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_RF_SEQUENCE);
}

static inline bool
rt2x00_has_cap_external_lna_a(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_EXTERNAL_LNA_A);
}

static inline bool
rt2x00_has_cap_external_lna_bg(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_EXTERNAL_LNA_BG);
}

static inline bool
rt2x00_has_cap_double_antenna(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_DOUBLE_ANTENNA);
}

static inline bool
rt2x00_has_cap_bt_coexist(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_BT_COEXIST);
}

static inline bool
rt2x00_has_cap_vco_recalibration(struct rt2x00_dev *rt2x00dev)
{
        return rt2x00_has_cap_flag(rt2x00dev, CAPABILITY_VCO_RECALIBRATION);
}

/**
 * rt2x00queue_map_txskb - Map a skb into DMA for TX purposes.
 * @entry: Pointer to &struct queue_entry
 *
 * Returns -ENOMEM if mapping fail, 0 otherwise.
 */
int rt2x00queue_map_txskb(struct queue_entry *entry);

/**
 * rt2x00queue_unmap_skb - Unmap a skb from DMA.
 * @entry: Pointer to &struct queue_entry
 */
void rt2x00queue_unmap_skb(struct queue_entry *entry);

/**
 * rt2x00queue_get_tx_queue - Convert tx queue index to queue pointer
 * @rt2x00dev: Pointer to &struct rt2x00_dev.
 * @queue: rt2x00 queue index (see &enum data_queue_qid).
 *
 * Returns NULL for non tx queues.
 */
static inline struct data_queue *
rt2x00queue_get_tx_queue(struct rt2x00_dev *rt2x00dev,
                         const enum data_queue_qid queue)
{
        if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
                return &rt2x00dev->tx[queue];

        if (queue == QID_ATIM)
                return rt2x00dev->atim;

        return NULL;
}

/**
 * rt2x00queue_get_entry - Get queue entry where the given index points to.
 * @queue: Pointer to &struct data_queue from where we obtain the entry.
 * @index: Index identifier for obtaining the correct index.
 */
struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
                                          enum queue_index index);

/**
 * rt2x00queue_pause_queue - Pause a data queue
 * @queue: Pointer to &struct data_queue.
 *
 * This function will pause the data queue locally, preventing
 * new frames to be added to the queue (while the hardware is
 * still allowed to run).
 */
void rt2x00queue_pause_queue(struct data_queue *queue);

/**
 * rt2x00queue_unpause_queue - unpause a data queue
 * @queue: Pointer to &struct data_queue.
 *
 * This function will unpause the data queue locally, allowing
 * new frames to be added to the queue again.
 */
void rt2x00queue_unpause_queue(struct data_queue *queue);

/**
 * rt2x00queue_start_queue - Start a data queue
 * @queue: Pointer to &struct data_queue.
 *
 * This function will start handling all pending frames in the queue.
 */
void rt2x00queue_start_queue(struct data_queue *queue);

/**
 * rt2x00queue_stop_queue - Halt a data queue
 * @queue: Pointer to &struct data_queue.
 *
 * This function will stop all pending frames in the queue.
 */
void rt2x00queue_stop_queue(struct data_queue *queue);

/**
 * rt2x00queue_flush_queue - Flush a data queue
 * @queue: Pointer to &struct data_queue.
 * @drop: True to drop all pending frames.
 *
 * This function will flush the queue. After this call
 * the queue is guaranteed to be empty.
 */
void rt2x00queue_flush_queue(struct data_queue *queue, bool drop);

/**
 * rt2x00queue_start_queues - Start all data queues
 * @rt2x00dev: Pointer to &struct rt2x00_dev.
 *
 * This function will loop through all available queues to start them
 */
void rt2x00queue_start_queues(struct rt2x00_dev *rt2x00dev);

/**
 * rt2x00queue_stop_queues - Halt all data queues
 * @rt2x00dev: Pointer to &struct rt2x00_dev.
 *
 * This function will loop through all available queues to stop
 * any pending frames.
 */
void rt2x00queue_stop_queues(struct rt2x00_dev *rt2x00dev);

/**
 * rt2x00queue_flush_queues - Flush all data queues
 * @rt2x00dev: Pointer to &struct rt2x00_dev.
 * @drop: True to drop all pending frames.
 *
 * This function will loop through all available queues to flush
 * any pending frames.
 */
void rt2x00queue_flush_queues(struct rt2x00_dev *rt2x00dev, bool drop);

/*
 * Debugfs handlers.
 */
/**
 * rt2x00debug_dump_frame - Dump a frame to userspace through debugfs.
 * @rt2x00dev: Pointer to &struct rt2x00_dev.
 * @type: The type of frame that is being dumped.
 * @entry: The queue entry containing the frame to be dumped.
 */
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
void rt2x00debug_dump_frame(struct rt2x00_dev *rt2x00dev,
                            enum rt2x00_dump_type type, struct queue_entry *entry);
#else
static inline void rt2x00debug_dump_frame(struct rt2x00_dev *rt2x00dev,
                                          enum rt2x00_dump_type type,
                                          struct queue_entry *entry)
{
}
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */

/*
 * Utility functions.
 */
u32 rt2x00lib_get_bssidx(struct rt2x00_dev *rt2x00dev,
                         struct ieee80211_vif *vif);
void rt2x00lib_set_mac_address(struct rt2x00_dev *rt2x00dev, u8 *eeprom_mac_addr);

/*
 * Interrupt context handlers.
 */
void rt2x00lib_beacondone(struct rt2x00_dev *rt2x00dev);
void rt2x00lib_pretbtt(struct rt2x00_dev *rt2x00dev);
void rt2x00lib_dmastart(struct queue_entry *entry);
void rt2x00lib_dmadone(struct queue_entry *entry);
void rt2x00lib_txdone(struct queue_entry *entry,
                      struct txdone_entry_desc *txdesc);
void rt2x00lib_txdone_nomatch(struct queue_entry *entry,
                              struct txdone_entry_desc *txdesc);
void rt2x00lib_txdone_noinfo(struct queue_entry *entry, u32 status);
void rt2x00lib_rxdone(struct queue_entry *entry, gfp_t gfp);

/*
 * mac80211 handlers.
 */
void rt2x00mac_tx(struct ieee80211_hw *hw,
                  struct ieee80211_tx_control *control,
                  struct sk_buff *skb);
int rt2x00mac_start(struct ieee80211_hw *hw);
void rt2x00mac_stop(struct ieee80211_hw *hw);
int rt2x00mac_add_interface(struct ieee80211_hw *hw,
                            struct ieee80211_vif *vif);
void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif);
int rt2x00mac_config(struct ieee80211_hw *hw, u32 changed);
void rt2x00mac_configure_filter(struct ieee80211_hw *hw,
                                unsigned int changed_flags,
                                unsigned int *total_flags,
                                u64 multicast);
int rt2x00mac_set_tim(struct ieee80211_hw *hw, struct ieee80211_sta *sta,
                      bool set);
#ifdef CONFIG_RT2X00_LIB_CRYPTO
int rt2x00mac_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
                      struct ieee80211_vif *vif, struct ieee80211_sta *sta,
                      struct ieee80211_key_conf *key);
#else
#define rt2x00mac_set_key       NULL
#endif /* CONFIG_RT2X00_LIB_CRYPTO */
int rt2x00mac_sta_add(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                      struct ieee80211_sta *sta);
int rt2x00mac_sta_remove(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                         struct ieee80211_sta *sta);
void rt2x00mac_sw_scan_start(struct ieee80211_hw *hw,
                             struct ieee80211_vif *vif,
                             const u8 *mac_addr);
void rt2x00mac_sw_scan_complete(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif);
int rt2x00mac_get_stats(struct ieee80211_hw *hw,
                        struct ieee80211_low_level_stats *stats);
void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif,
                                struct ieee80211_bss_conf *bss_conf,
                                u32 changes);
int rt2x00mac_conf_tx(struct ieee80211_hw *hw,
                      struct ieee80211_vif *vif, u16 queue,
                      const struct ieee80211_tx_queue_params *params);
void rt2x00mac_rfkill_poll(struct ieee80211_hw *hw);
void rt2x00mac_flush(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                     u32 queues, bool drop);
int rt2x00mac_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant);
int rt2x00mac_get_antenna(struct ieee80211_hw *hw, u32 *tx_ant, u32 *rx_ant);
void rt2x00mac_get_ringparam(struct ieee80211_hw *hw,
                             u32 *tx, u32 *tx_max, u32 *rx, u32 *rx_max);
bool rt2x00mac_tx_frames_pending(struct ieee80211_hw *hw);

/*
 * Driver allocation handlers.
 */
int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev);
void rt2x00lib_remove_dev(struct rt2x00_dev *rt2x00dev);
#ifdef CONFIG_PM
int rt2x00lib_suspend(struct rt2x00_dev *rt2x00dev, pm_message_t state);
int rt2x00lib_resume(struct rt2x00_dev *rt2x00dev);
#endif /* CONFIG_PM */

#endif /* RT2X00_H */