/*
 * Copyright (c) 2006 Damien Bergamini <damien.bergamini@free.fr>
 * Copyright (c) 2006 Sam Leffler, Errno Consulting
 * Copyright (c) 2007 Christoph Hellwig <hch@lst.de>
 * Copyright (c) 2008-2009 Weongyo Jeong <weongyo@freebsd.org>
 * Copyright (c) 2012 Pontus Fuchs <pontus.fuchs@gmail.com>
 *
 * 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.
 */

#define AR5523_FLAG_PRE_FIRMWARE        (1 << 0)
#define AR5523_FLAG_ABG                 (1 << 1)

#define AR5523_FIRMWARE_FILE    "ar5523.bin"

#define AR5523_CMD_TX_PIPE      0x01
#define AR5523_DATA_TX_PIPE     0x02
#define AR5523_CMD_RX_PIPE      0x81
#define AR5523_DATA_RX_PIPE     0x82

#define ar5523_cmd_tx_pipe(dev) \
        usb_sndbulkpipe((dev), AR5523_CMD_TX_PIPE)
#define ar5523_data_tx_pipe(dev) \
        usb_sndbulkpipe((dev), AR5523_DATA_TX_PIPE)
#define ar5523_cmd_rx_pipe(dev) \
        usb_rcvbulkpipe((dev), AR5523_CMD_RX_PIPE)
#define ar5523_data_rx_pipe(dev) \
        usb_rcvbulkpipe((dev), AR5523_DATA_RX_PIPE)

#define AR5523_DATA_TIMEOUT     10000
#define AR5523_CMD_TIMEOUT      1000

#define AR5523_TX_DATA_COUNT            8
#define AR5523_TX_DATA_RESTART_COUNT    2
#define AR5523_RX_DATA_COUNT            16
#define AR5523_RX_DATA_REFILL_COUNT     8

#define AR5523_CMD_ID   1
#define AR5523_DATA_ID  2

#define AR5523_TX_WD_TIMEOUT    (HZ * 2)
#define AR5523_FLUSH_TIMEOUT    (HZ * 3)

enum AR5523_flags {
        AR5523_HW_UP,
        AR5523_USB_DISCONNECTED,
        AR5523_CONNECTED
};

struct ar5523_tx_cmd {
        struct ar5523           *ar;
        struct urb              *urb_tx;
        void                    *buf_tx;
        void                    *odata;
        int                     olen;
        int                     flags;
        int                     res;
        struct completion       done;
};

/* This struct is placed in tx_info->driver_data. It must not be larger
 *  than IEEE80211_TX_INFO_DRIVER_DATA_SIZE.
 */
struct ar5523_tx_data {
        struct list_head        list;
        struct ar5523           *ar;
        struct urb              *urb;
};

struct ar5523_rx_data {
        struct  list_head       list;
        struct ar5523           *ar;
        struct urb              *urb;
        struct sk_buff          *skb;
};

struct ar5523 {
        struct usb_device       *dev;
        struct ieee80211_hw     *hw;

        unsigned long           flags;
        struct mutex            mutex;
        struct workqueue_struct *wq;

        struct ar5523_tx_cmd    tx_cmd;

        struct delayed_work     stat_work;

        struct timer_list       tx_wd_timer;
        struct work_struct      tx_wd_work;
        struct work_struct      tx_work;
        struct list_head        tx_queue_pending;
        struct list_head        tx_queue_submitted;
        spinlock_t              tx_data_list_lock;
        wait_queue_head_t       tx_flush_waitq;

        /* Queued + Submitted TX frames */
        atomic_t                tx_nr_total;

        /* Submitted TX frames */
        atomic_t                tx_nr_pending;

        void                    *rx_cmd_buf;
        struct urb              *rx_cmd_urb;

        struct ar5523_rx_data   rx_data[AR5523_RX_DATA_COUNT];
        spinlock_t              rx_data_list_lock;
        struct list_head        rx_data_free;
        struct list_head        rx_data_used;
        atomic_t                rx_data_free_cnt;

        struct work_struct      rx_refill_work;

        unsigned int            rxbufsz;
        u8                      serial[16];

        struct ieee80211_channel channels[14];
        struct ieee80211_rate   rates[12];
        struct ieee80211_supported_band band;
        struct ieee80211_vif    *vif;
};

/* flags for sending firmware commands */
#define AR5523_CMD_FLAG_READ    (1 << 1)
#define AR5523_CMD_FLAG_MAGIC   (1 << 2)

#define ar5523_dbg(ar, format, arg...) \
        dev_dbg(&(ar)->dev->dev, format, ## arg)

/* On USB hot-unplug there can be a lot of URBs in flight and they'll all
 * fail. Instead of dealing with them in every possible place just surpress
 * any messages on USB disconnect.
 */
#define ar5523_err(ar, format, arg...) \
do { \
        if (!test_bit(AR5523_USB_DISCONNECTED, &ar->flags)) { \
                dev_err(&(ar)->dev->dev, format, ## arg); \
        } \
} while (0)
#define ar5523_info(ar, format, arg...) \
        dev_info(&(ar)->dev->dev, format, ## arg)