Add rt2x00-mac80211 snapshot (#1916)

[openwrt/svn-archive/archive.git] / package / rt2x00 / src / rt2400pci.c

/*
        Copyright (C) 2004 - 2007 rt2x00 SourceForge Project
        <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, write to the
        Free Software Foundation, Inc.,
        59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
        Module: rt2400pci
        Abstract: rt2400pci device specific routines.
        Supported chipsets: RT2460.
 */

/*
 * Set enviroment defines for rt2x00.h
 */
#define DRV_NAME "rt2400pci"

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/eeprom_93cx6.h>

#include <asm/io.h>

#include "rt2x00.h"
#include "rt2x00pci.h"
#include "rt2400pci.h"

/*
 * Register access.
 * All access to the CSR registers will go through the methods
 * rt2x00pci_register_read and rt2x00pci_register_write.
 * BBP and RF register require indirect register access,
 * and use the CSR registers BBPCSR and RFCSR to achieve this.
 * These indirect registers work with busy bits,
 * and we will try maximal REGISTER_BUSY_COUNT times to access
 * the register while taking a REGISTER_BUSY_DELAY us delay
 * between each attampt. When the busy bit is still set at that time,
 * the access attempt is considered to have failed,
 * and we will print an error.
 */
static u32 rt2400pci_bbp_check(const struct rt2x00_dev *rt2x00dev)
{
        u32 reg;
        unsigned int i;

        for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
                rt2x00pci_register_read(rt2x00dev, BBPCSR, &reg);
                if (!rt2x00_get_field32(reg, BBPCSR_BUSY))
                        break;
                udelay(REGISTER_BUSY_DELAY);
        }

        return reg;
}

static void rt2400pci_bbp_write(const struct rt2x00_dev *rt2x00dev,
        const u8 reg_id, const u8 value)
{
        u32 reg;

        /*
         *  Wait until the BBP becomes ready.
         */
        reg = rt2400pci_bbp_check(rt2x00dev);
        if (rt2x00_get_field32(reg, BBPCSR_BUSY)) {
                ERROR(rt2x00dev, "BBPCSR register busy. Write failed.\n");
                return;
        }

        /*
         * Write the data into the BBP.
         */
        reg = 0;
        rt2x00_set_field32(&reg, BBPCSR_VALUE, value);
        rt2x00_set_field32(&reg, BBPCSR_REGNUM, reg_id);
        rt2x00_set_field32(&reg, BBPCSR_BUSY, 1);
        rt2x00_set_field32(&reg, BBPCSR_WRITE_CONTROL, 1);

        rt2x00pci_register_write(rt2x00dev, BBPCSR, reg);
}

static void rt2400pci_bbp_read(const struct rt2x00_dev *rt2x00dev,
        const u8 reg_id, u8 *value)
{
        u32 reg;

        /*
         *  Wait until the BBP becomes ready.
         */
        reg = rt2400pci_bbp_check(rt2x00dev);
        if (rt2x00_get_field32(reg, BBPCSR_BUSY)) {
                ERROR(rt2x00dev, "BBPCSR register busy. Read failed.\n");
                return;
        }

        /*
         * Write the request into the BBP.
         */
        reg = 0;
        rt2x00_set_field32(&reg, BBPCSR_REGNUM, reg_id);
        rt2x00_set_field32(&reg, BBPCSR_BUSY, 1);
        rt2x00_set_field32(&reg, BBPCSR_WRITE_CONTROL, 0);

        rt2x00pci_register_write(rt2x00dev, BBPCSR, reg);

        /*
         *  Wait until the BBP becomes ready.
         */
        reg = rt2400pci_bbp_check(rt2x00dev);
        if (rt2x00_get_field32(reg, BBPCSR_BUSY)) {
                ERROR(rt2x00dev, "BBPCSR register busy. Read failed.\n");
                *value = 0xff;
                return;
        }

        *value = rt2x00_get_field32(reg, BBPCSR_VALUE);
}

static void rt2400pci_rf_write(const struct rt2x00_dev *rt2x00dev,
        const u32 value)
{
        u32 reg;
        unsigned int i;

        for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
                rt2x00pci_register_read(rt2x00dev, RFCSR, &reg);
                if (!rt2x00_get_field32(reg, RFCSR_BUSY))
                        goto rf_write;
                udelay(REGISTER_BUSY_DELAY);
        }

        ERROR(rt2x00dev, "RFCSR register busy. Write failed.\n");
        return;

rf_write:
        reg = 0;
        rt2x00_set_field32(&reg, RFCSR_VALUE, value);
        rt2x00_set_field32(&reg, RFCSR_NUMBER_OF_BITS, 20);
        rt2x00_set_field32(&reg, RFCSR_IF_SELECT, 0);
        rt2x00_set_field32(&reg, RFCSR_BUSY, 1);

        rt2x00pci_register_write(rt2x00dev, RFCSR, reg);
}

static void rt2400pci_eepromregister_read(struct eeprom_93cx6 *eeprom)
{
        struct rt2x00_dev *rt2x00dev = eeprom->data;
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, CSR21, &reg);

        eeprom->reg_data_in = !!rt2x00_get_field32(reg,
                CSR21_EEPROM_DATA_IN);
        eeprom->reg_data_out = !!rt2x00_get_field32(reg,
                CSR21_EEPROM_DATA_OUT);
        eeprom->reg_data_clock = !!rt2x00_get_field32(reg,
                CSR21_EEPROM_DATA_CLOCK);
        eeprom->reg_chip_select = !!rt2x00_get_field32(reg,
                CSR21_EEPROM_CHIP_SELECT);
}

static void rt2400pci_eepromregister_write(struct eeprom_93cx6 *eeprom)
{
        struct rt2x00_dev *rt2x00dev = eeprom->data;
        u32 reg = 0;

        rt2x00_set_field32(&reg, CSR21_EEPROM_DATA_IN,
                !!eeprom->reg_data_in);
        rt2x00_set_field32(&reg, CSR21_EEPROM_DATA_OUT,
                !!eeprom->reg_data_out);
        rt2x00_set_field32(&reg, CSR21_EEPROM_DATA_CLOCK,
                !!eeprom->reg_data_clock);
        rt2x00_set_field32(&reg, CSR21_EEPROM_CHIP_SELECT,
                !!eeprom->reg_chip_select);

        rt2x00pci_register_write(rt2x00dev, CSR21, reg);
}

#ifdef CONFIG_RT2X00_LIB_DEBUGFS
#define CSR_OFFSET(__word)      ( CSR_REG_BASE + ((__word) * sizeof(u32)) )

static void rt2400pci_read_csr(struct rt2x00_dev *rt2x00dev,
        const unsigned long word, void *data)
{
        rt2x00pci_register_read(rt2x00dev, CSR_OFFSET(word), data);
}

static void rt2400pci_write_csr(struct rt2x00_dev *rt2x00dev,
        const unsigned long word, void *data)
{
        rt2x00pci_register_write(rt2x00dev, CSR_OFFSET(word), *((u32*)data));
}

static void rt2400pci_read_eeprom(struct rt2x00_dev *rt2x00dev,
        const unsigned long word, void *data)
{
        rt2x00_eeprom_read(rt2x00dev, word, data);
}

static void rt2400pci_write_eeprom(struct rt2x00_dev *rt2x00dev,
        const unsigned long word, void *data)
{
        rt2x00_eeprom_write(rt2x00dev, word, *((u16*)data));
}

static void rt2400pci_read_bbp(struct rt2x00_dev *rt2x00dev,
        const unsigned long word, void *data)
{
        rt2400pci_bbp_read(rt2x00dev, word, data);
}

static void rt2400pci_write_bbp(struct rt2x00_dev *rt2x00dev,
        const unsigned long word, void *data)
{
        rt2400pci_bbp_write(rt2x00dev, word, *((u8*)data));
}

static const struct rt2x00debug rt2400pci_rt2x00debug = {
        .owner          = THIS_MODULE,
        .reg_csr        = {
                .read           = rt2400pci_read_csr,
                .write          = rt2400pci_write_csr,
                .word_size      = sizeof(u32),
                .word_count     = CSR_REG_SIZE / sizeof(u32),
        },
        .reg_eeprom     = {
                .read           = rt2400pci_read_eeprom,
                .write          = rt2400pci_write_eeprom,
                .word_size      = sizeof(u16),
                .word_count     = EEPROM_SIZE / sizeof(u16),
        },
        .reg_bbp        = {
                .read           = rt2400pci_read_bbp,
                .write          = rt2400pci_write_bbp,
                .word_size      = sizeof(u8),
                .word_count     = BBP_SIZE / sizeof(u8),
        },
};
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */

#ifdef CONFIG_RT2400PCI_RFKILL
static int rt2400pci_rfkill_poll(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, GPIOCSR, &reg);
        return rt2x00_get_field32(reg, GPIOCSR_BIT0);
}
#endif /* CONFIG_RT2400PCI_RFKILL */

/*
 * Configuration handlers.
 */
static void rt2400pci_config_bssid(struct rt2x00_dev *rt2x00dev, u8 *bssid)
{
        u32 reg[2];

        memset(&reg, 0, sizeof(reg));
        memcpy(&reg, bssid, ETH_ALEN);

        /*
         * The BSSID is passed to us as an array of bytes,
         * that array is little endian, so no need for byte ordering.
         */
        rt2x00pci_register_multiwrite(rt2x00dev, CSR5, &reg, sizeof(reg));
}

static void rt2400pci_config_promisc(struct rt2x00_dev *rt2x00dev,
        const int promisc)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, RXCSR0, &reg);
        rt2x00_set_field32(&reg, RXCSR0_DROP_NOT_TO_ME, !promisc);
        rt2x00pci_register_write(rt2x00dev, RXCSR0, reg);
}

static void rt2400pci_config_type(struct rt2x00_dev *rt2x00dev, int type)
{
        u32 reg;

        rt2x00pci_register_write(rt2x00dev, CSR14, 0);

        /*
         * Apply hardware packet filter.
         */
        rt2x00pci_register_read(rt2x00dev, RXCSR0, &reg);

        if (!is_monitor_present(&rt2x00dev->interface) &&
            (type == IEEE80211_IF_TYPE_IBSS || type == IEEE80211_IF_TYPE_STA))
                rt2x00_set_field32(&reg, RXCSR0_DROP_TODS, 1);
        else
                rt2x00_set_field32(&reg, RXCSR0_DROP_TODS, 0);

        rt2x00_set_field32(&reg, RXCSR0_DROP_CRC, 1);
        if (is_monitor_present(&rt2x00dev->interface)) {
                rt2x00_set_field32(&reg, RXCSR0_DROP_PHYSICAL, 0);
                rt2x00_set_field32(&reg, RXCSR0_DROP_CONTROL, 0);
                rt2x00_set_field32(&reg, RXCSR0_DROP_VERSION_ERROR, 0);
        } else {
                rt2x00_set_field32(&reg, RXCSR0_DROP_PHYSICAL, 1);
                rt2x00_set_field32(&reg, RXCSR0_DROP_CONTROL, 1);
                rt2x00_set_field32(&reg, RXCSR0_DROP_VERSION_ERROR, 1);
        }

        rt2x00pci_register_write(rt2x00dev, RXCSR0, reg);

        /*
         * Enable beacon config
         */
        rt2x00pci_register_read(rt2x00dev, BCNCSR1, &reg);
        rt2x00_set_field32(&reg, BCNCSR1_PRELOAD,
                PREAMBLE + get_duration(IEEE80211_HEADER, 2));
        rt2x00pci_register_write(rt2x00dev, BCNCSR1, reg);

        /*
         * Enable synchronisation.
         */
        rt2x00pci_register_read(rt2x00dev, CSR14, &reg);
        if (is_interface_present(&rt2x00dev->interface)) {
                rt2x00_set_field32(&reg, CSR14_TSF_COUNT, 1);
                rt2x00_set_field32(&reg, CSR14_TBCN, 1);
        }

        rt2x00_set_field32(&reg, CSR14_BEACON_GEN, 0);
        if (type == IEEE80211_IF_TYPE_IBSS || type == IEEE80211_IF_TYPE_AP)
                rt2x00_set_field32(&reg, CSR14_TSF_SYNC, 2);
        else if (type == IEEE80211_IF_TYPE_STA)
                rt2x00_set_field32(&reg, CSR14_TSF_SYNC, 1);
        else if (is_monitor_present(&rt2x00dev->interface) &&
                 !is_interface_present(&rt2x00dev->interface))
                rt2x00_set_field32(&reg, CSR14_TSF_SYNC, 0);

        rt2x00pci_register_write(rt2x00dev, CSR14, reg);
}

static void rt2400pci_config_channel(struct rt2x00_dev *rt2x00dev,
        const int value, const int channel, const int txpower)
{
        u32 rf1 = rt2x00dev->rf1;
        u32 rf2 = value;
        u32 rf3 = rt2x00dev->rf3;

        /*
         * Switch on tuning bits.
         */
        rt2x00_set_field32(&rf1, RF1_TUNER, 1);
        rt2x00_set_field32(&rf3, RF3_TUNER, 1);

        rt2400pci_rf_write(rt2x00dev, rf1);
        rt2400pci_rf_write(rt2x00dev, rf2);
        rt2400pci_rf_write(rt2x00dev, rf3);

        /*
         * RF2420 chipset don't need any additional actions.
         */
        if (rt2x00_rf(&rt2x00dev->chip, RF2420))
                return;

        /*
         * For the RT2421 chipsets we need to write an invalid
         * reference clock rate to activate auto_tune.
         * After that we set the value back to the correct channel.
         */
        rt2400pci_rf_write(rt2x00dev, rf1);
        rt2400pci_rf_write(rt2x00dev, 0x000c2a32);
        rt2400pci_rf_write(rt2x00dev, rf3);

        msleep(1);

        rt2400pci_rf_write(rt2x00dev, rf1);
        rt2400pci_rf_write(rt2x00dev, rf2);
        rt2400pci_rf_write(rt2x00dev, rf3);

        msleep(1);

        /*
         * Switch off tuning bits.
         */
        rt2x00_set_field32(&rf1, RF1_TUNER, 0);
        rt2x00_set_field32(&rf3, RF3_TUNER, 0);

        rt2400pci_rf_write(rt2x00dev, rf1);
        rt2400pci_rf_write(rt2x00dev, rf3);

        /*
         * Update rf fields
         */
        rt2x00dev->rf1 = rf1;
        rt2x00dev->rf2 = rf2;
        rt2x00dev->rf3 = rf3;

        /*
         * Clear false CRC during channel switch.
         */
        rt2x00pci_register_read(rt2x00dev, CNT0, &rf1);
}

static void rt2400pci_config_txpower(struct rt2x00_dev *rt2x00dev, int txpower)
{
        rt2400pci_bbp_write(rt2x00dev, 3, TXPOWER_TO_DEV(txpower));
}

static void rt2400pci_config_antenna(struct rt2x00_dev *rt2x00dev,
        int antenna_tx, int antenna_rx)
{
        u8 r1;
        u8 r4;

        rt2400pci_bbp_read(rt2x00dev, 4, &r4);
        rt2400pci_bbp_read(rt2x00dev, 1, &r1);

        /*
         * Configure the TX antenna.
         */
        if (antenna_tx == ANTENNA_DIVERSITY)
                rt2x00_set_field8(&r1, BBP_R1_TX_ANTENNA, 1);
        else if (antenna_tx == ANTENNA_A)
                rt2x00_set_field8(&r1, BBP_R1_TX_ANTENNA, 0);
        else if (antenna_tx == ANTENNA_B)
                rt2x00_set_field8(&r1, BBP_R1_TX_ANTENNA, 2);

        /*
         * Configure the RX antenna.
         */
        if (antenna_rx == ANTENNA_DIVERSITY)
                rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA, 1);
        else if (antenna_rx == ANTENNA_A)
                rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA, 0);
        else if (antenna_rx == ANTENNA_B)
                rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA, 2);

        rt2400pci_bbp_write(rt2x00dev, 4, r4);
        rt2400pci_bbp_write(rt2x00dev, 1, r1);
}

static void rt2400pci_config_cw(struct rt2x00_dev *rt2x00dev,
        struct ieee80211_tx_queue_params *params)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, CSR11, &reg);
        rt2x00_set_field32(&reg, CSR11_CWMIN, params->cw_min);
        rt2x00_set_field32(&reg, CSR11_CWMAX, params->cw_max);
        rt2x00pci_register_write(rt2x00dev, CSR11, reg);
}

static void rt2400pci_config_duration(struct rt2x00_dev *rt2x00dev,
        int short_slot_time, int beacon_int)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, CSR11, &reg);
        rt2x00_set_field32(&reg, CSR11_SLOT_TIME,
                short_slot_time ? SHORT_SLOT_TIME : SLOT_TIME);
        rt2x00pci_register_write(rt2x00dev, CSR11, reg);

        rt2x00pci_register_read(rt2x00dev, CSR18, &reg);
        rt2x00_set_field32(&reg, CSR18_SIFS, SIFS);
        rt2x00_set_field32(&reg, CSR18_PIFS,
                short_slot_time ? SHORT_PIFS :  PIFS);
        rt2x00pci_register_write(rt2x00dev, CSR18, reg);

        rt2x00pci_register_read(rt2x00dev, CSR19, &reg);
        rt2x00_set_field32(&reg, CSR19_DIFS,
                short_slot_time ? SHORT_DIFS : DIFS);
        rt2x00_set_field32(&reg, CSR19_EIFS, EIFS);
        rt2x00pci_register_write(rt2x00dev, CSR19, reg);

        rt2x00pci_register_read(rt2x00dev, TXCSR1, &reg);
        rt2x00_set_field32(&reg, TXCSR1_TSF_OFFSET, IEEE80211_HEADER);
        rt2x00_set_field32(&reg, TXCSR1_AUTORESPONDER, 1);
        rt2x00pci_register_write(rt2x00dev, TXCSR1, reg);

        rt2x00pci_register_read(rt2x00dev, CSR12, &reg);
        rt2x00_set_field32(&reg, CSR12_BEACON_INTERVAL, beacon_int * 16);
        rt2x00_set_field32(&reg, CSR12_CFP_MAX_DURATION, beacon_int * 16);
        rt2x00pci_register_write(rt2x00dev, CSR12, reg);
}

static void rt2400pci_config_rate(struct rt2x00_dev *rt2x00dev, const int rate)
{
        struct ieee80211_conf *conf = &rt2x00dev->hw->conf;
        u32 reg;
        u32 preamble;
        u16 value;

        preamble = DEVICE_GET_RATE_FIELD(rate, PREAMBLE)
                ? SHORT_PREAMBLE : PREAMBLE;

        reg = DEVICE_GET_RATE_FIELD(rate, RATEMASK) & DEV_BASIC_RATE;
        rt2x00pci_register_write(rt2x00dev, ARCSR1, reg);

        rt2x00pci_register_read(rt2x00dev, TXCSR1, &reg);
        value = ((conf->flags & IEEE80211_CONF_SHORT_SLOT_TIME) ?
                 SHORT_DIFS :  DIFS) +
                PLCP + preamble + get_duration(ACK_SIZE, 10);
        rt2x00_set_field32(&reg, TXCSR1_ACK_TIMEOUT, value);
        value = SIFS + PLCP + preamble + get_duration(ACK_SIZE, 10);
        rt2x00_set_field32(&reg, TXCSR1_ACK_CONSUME_TIME, value);
        rt2x00pci_register_write(rt2x00dev, TXCSR1, reg);

        preamble = DEVICE_GET_RATE_FIELD(rate, PREAMBLE) ? 0x08 : 0x00;

        rt2x00pci_register_read(rt2x00dev, ARCSR2, &reg);
        rt2x00_set_field32(&reg, ARCSR2_SIGNAL, 0x00 | preamble);
        rt2x00_set_field32(&reg, ARCSR2_SERVICE, 0x04);
        rt2x00_set_field32(&reg, ARCSR2_LENGTH, get_duration(ACK_SIZE, 10));
        rt2x00pci_register_write(rt2x00dev, ARCSR2, reg);

        rt2x00pci_register_read(rt2x00dev, ARCSR3, &reg);
        rt2x00_set_field32(&reg, ARCSR3_SIGNAL, 0x01 | preamble);
        rt2x00_set_field32(&reg, ARCSR3_SERVICE, 0x04);
        rt2x00_set_field32(&reg, ARCSR2_LENGTH, get_duration(ACK_SIZE, 20));
        rt2x00pci_register_write(rt2x00dev, ARCSR3, reg);

        rt2x00pci_register_read(rt2x00dev, ARCSR4, &reg);
        rt2x00_set_field32(&reg, ARCSR4_SIGNAL, 0x02 | preamble);
        rt2x00_set_field32(&reg, ARCSR4_SERVICE, 0x04);
        rt2x00_set_field32(&reg, ARCSR2_LENGTH, get_duration(ACK_SIZE, 55));
        rt2x00pci_register_write(rt2x00dev, ARCSR4, reg);

        rt2x00pci_register_read(rt2x00dev, ARCSR5, &reg);
        rt2x00_set_field32(&reg, ARCSR5_SIGNAL, 0x03 | preamble);
        rt2x00_set_field32(&reg, ARCSR5_SERVICE, 0x84);
        rt2x00_set_field32(&reg, ARCSR2_LENGTH, get_duration(ACK_SIZE, 110));
        rt2x00pci_register_write(rt2x00dev, ARCSR5, reg);
}

static void rt2400pci_config_phymode(struct rt2x00_dev *rt2x00dev,
        const int phymode)
{
        struct ieee80211_hw_mode *mode;
        struct ieee80211_rate *rate;

        rt2x00dev->curr_hwmode = HWMODE_B;

        mode = &rt2x00dev->hwmodes[rt2x00dev->curr_hwmode];
        rate = &mode->rates[mode->num_rates - 1];

        rt2400pci_config_rate(rt2x00dev, rate->val2);
}

static void rt2400pci_config_mac_addr(struct rt2x00_dev *rt2x00dev, u8 *addr)
{
        u32 reg[2];

        memset(&reg, 0, sizeof(reg));
        memcpy(&reg, addr, ETH_ALEN);

        /*
         * The MAC address is passed to us as an array of bytes,
         * that array is little endian, so no need for byte ordering.
         */
        rt2x00pci_register_multiwrite(rt2x00dev, CSR3, &reg, sizeof(reg));
}

/*
 * LED functions.
 */
static void rt2400pci_enable_led(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, LEDCSR, &reg);

        rt2x00_set_field32(&reg, LEDCSR_ON_PERIOD, 70);
        rt2x00_set_field32(&reg, LEDCSR_OFF_PERIOD, 30);

        if (rt2x00dev->led_mode == LED_MODE_TXRX_ACTIVITY) {
                rt2x00_set_field32(&reg, LEDCSR_LINK, 1);
                rt2x00_set_field32(&reg, LEDCSR_ACTIVITY, 0);
        } else if (rt2x00dev->led_mode == LED_MODE_ASUS) {
                rt2x00_set_field32(&reg, LEDCSR_LINK, 0);
                rt2x00_set_field32(&reg, LEDCSR_ACTIVITY, 1);
        } else {
                rt2x00_set_field32(&reg, LEDCSR_LINK, 1);
                rt2x00_set_field32(&reg, LEDCSR_ACTIVITY, 1);
        }

        rt2x00pci_register_write(rt2x00dev, LEDCSR, reg);
}

static void rt2400pci_disable_led(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, LEDCSR, &reg);
        rt2x00_set_field32(&reg, LEDCSR_LINK, 0);
        rt2x00_set_field32(&reg, LEDCSR_ACTIVITY, 0);
        rt2x00pci_register_write(rt2x00dev, LEDCSR, reg);
}

/*
 * Link tuning
 */
static void rt2400pci_link_tuner(struct rt2x00_dev *rt2x00dev, int rssi)
{
        u8 reg;
        char false_cca_delta;

        /*
         * The link tuner should not run longer then 60 seconds,
         * and should run once every 2 seconds.
         */
        if (rt2x00dev->link.count > 60 || !(rt2x00dev->link.count % 1))
                return;

        /*
         * Read false CCA counter.
         */
        rt2400pci_bbp_read(rt2x00dev, 39, &reg);

        /*
         * Determine difference with previous CCA counter.
         */
        false_cca_delta = reg - rt2x00dev->link.false_cca;
        rt2x00dev->link.false_cca = reg;

        /*
         * Check if the difference is higher than the
         * threshold and if so, tune the link.
         */
        if (false_cca_delta >= 8) {
                /*
                 * Read and update RX AGC VGC.
                 */
                rt2400pci_bbp_read(rt2x00dev, 13, &reg);
                reg += 2;
                if (reg < 0x20)
                        rt2400pci_bbp_write(rt2x00dev, 13, reg);
        }
}

/*
 * Initialization functions.
 */
static void rt2400pci_init_rxring(struct rt2x00_dev *rt2x00dev)
{
        struct data_desc *rxd;
        unsigned int i;
        u32 word;

        memset(rt2x00dev->rx->data_addr, 0x00,
                rt2x00_get_ring_size(rt2x00dev->rx));

        for (i = 0; i < rt2x00dev->rx->stats.limit; i++) {
                rxd = rt2x00dev->rx->entry[i].priv;

                rt2x00_desc_read(rxd, 2, &word);
                rt2x00_set_field32(&word, RXD_W2_BUFFER_LENGTH,
                        rt2x00dev->rx->data_size);
                rt2x00_desc_write(rxd, 2, word);

                rt2x00_desc_read(rxd, 1, &word);
                rt2x00_set_field32(&word, RXD_W1_BUFFER_ADDRESS,
                        rt2x00dev->rx->entry[i].data_dma);
                rt2x00_desc_write(rxd, 1, word);

                rt2x00_desc_read(rxd, 0, &word);
                rt2x00_set_field32(&word, RXD_W0_OWNER_NIC, 1);
                rt2x00_desc_write(rxd, 0, word);
        }

        rt2x00_ring_index_clear(rt2x00dev->rx);
}

static void rt2400pci_init_txring(struct rt2x00_dev *rt2x00dev,
        const int queue)
{
        struct data_ring *ring = rt2x00_get_ring(rt2x00dev, queue);
        struct data_desc *txd;
        unsigned int i;
        u32 word;

        memset(ring->data_addr, 0x00, rt2x00_get_ring_size(ring));

        for (i = 0; i < ring->stats.limit; i++) {
                txd = ring->entry[i].priv;

                rt2x00_desc_read(txd, 1, &word);
                rt2x00_set_field32(&word, TXD_W1_BUFFER_ADDRESS,
                        ring->entry[i].data_dma);
                rt2x00_desc_write(txd, 1, word);

                rt2x00_desc_read(txd, 2, &word);
                rt2x00_set_field32(&word, TXD_W2_BUFFER_LENGTH,
                        ring->data_size);
                rt2x00_desc_write(txd, 2, word);

                rt2x00_desc_read(txd, 0, &word);
                rt2x00_set_field32(&word, TXD_W0_VALID, 0);
                rt2x00_set_field32(&word, TXD_W0_OWNER_NIC, 0);
                rt2x00_desc_write(txd, 0, word);
        }

        rt2x00_ring_index_clear(ring);
}

static int rt2400pci_init_rings(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        /*
         * Initialize rings.
         */
        rt2400pci_init_rxring(rt2x00dev);
        rt2400pci_init_txring(rt2x00dev, IEEE80211_TX_QUEUE_DATA0);
        rt2400pci_init_txring(rt2x00dev, IEEE80211_TX_QUEUE_DATA1);
        rt2400pci_init_txring(rt2x00dev, IEEE80211_TX_QUEUE_AFTER_BEACON);
        rt2400pci_init_txring(rt2x00dev, IEEE80211_TX_QUEUE_BEACON);

        /*
         * Initialize registers.
         */
        rt2x00pci_register_read(rt2x00dev, TXCSR2, &reg);
        rt2x00_set_field32(&reg, TXCSR2_TXD_SIZE,
                rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA0].desc_size);
        rt2x00_set_field32(&reg, TXCSR2_NUM_TXD,
                rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA1].stats.limit);
        rt2x00_set_field32(&reg, TXCSR2_NUM_ATIM,
                rt2x00dev->bcn[1].stats.limit);
        rt2x00_set_field32(&reg, TXCSR2_NUM_PRIO,
                rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA0].stats.limit);
        rt2x00pci_register_write(rt2x00dev, TXCSR2, reg);

        rt2x00pci_register_read(rt2x00dev, TXCSR3, &reg);
        rt2x00_set_field32(&reg, TXCSR3_TX_RING_REGISTER,
                rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA1].data_dma);
        rt2x00pci_register_write(rt2x00dev, TXCSR3, reg);

        rt2x00pci_register_read(rt2x00dev, TXCSR5, &reg);
        rt2x00_set_field32(&reg, TXCSR5_PRIO_RING_REGISTER,
                rt2x00dev->tx[IEEE80211_TX_QUEUE_DATA0].data_dma);
        rt2x00pci_register_write(rt2x00dev, TXCSR5, reg);

        rt2x00pci_register_read(rt2x00dev, TXCSR4, &reg);
        rt2x00_set_field32(&reg, TXCSR4_ATIM_RING_REGISTER,
                rt2x00dev->bcn[1].data_dma);
        rt2x00pci_register_write(rt2x00dev, TXCSR4, reg);

        rt2x00pci_register_read(rt2x00dev, TXCSR6, &reg);
        rt2x00_set_field32(&reg, TXCSR6_BEACON_RING_REGISTER,
                rt2x00dev->bcn[0].data_dma);
        rt2x00pci_register_write(rt2x00dev, TXCSR6, reg);

        rt2x00pci_register_read(rt2x00dev, RXCSR1, &reg);
        rt2x00_set_field32(&reg, RXCSR1_RXD_SIZE,
                rt2x00dev->rx->desc_size);
        rt2x00_set_field32(&reg, RXCSR1_NUM_RXD,
                rt2x00dev->rx->stats.limit);
        rt2x00pci_register_write(rt2x00dev, RXCSR1, reg);

        rt2x00pci_register_read(rt2x00dev, RXCSR2, &reg);
        rt2x00_set_field32(&reg, RXCSR2_RX_RING_REGISTER,
                rt2x00dev->rx->data_dma);
        rt2x00pci_register_write(rt2x00dev, RXCSR2, reg);

        return 0;
}

static int rt2400pci_init_registers(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        if (rt2x00dev->ops->lib->set_device_state(rt2x00dev, STATE_AWAKE))
                return -EBUSY;

        rt2x00pci_register_write(rt2x00dev, PWRCSR0, 0x3f3b3100);

        rt2x00pci_register_write(rt2x00dev, PSCSR0, 0x00020002);
        rt2x00pci_register_write(rt2x00dev, PSCSR1, 0x00000002);
        rt2x00pci_register_write(rt2x00dev, PSCSR2, 0x00020002);
        rt2x00pci_register_write(rt2x00dev, PSCSR3, 0x00000002);

        rt2x00pci_register_read(rt2x00dev, TIMECSR, &reg);
        rt2x00_set_field32(&reg, TIMECSR_US_COUNT, 33);
        rt2x00_set_field32(&reg, TIMECSR_US_64_COUNT, 63);
        rt2x00_set_field32(&reg, TIMECSR_BEACON_EXPECT, 0);
        rt2x00pci_register_write(rt2x00dev, TIMECSR, reg);

        rt2x00pci_register_read(rt2x00dev, CSR9, &reg);
        rt2x00_set_field32(&reg, CSR9_MAX_FRAME_UNIT,
                (rt2x00dev->rx->data_size / 128));
        rt2x00pci_register_write(rt2x00dev, CSR9, reg);

        rt2x00pci_register_write(rt2x00dev, CNT3, 0x3f080000);

        rt2x00pci_register_write(rt2x00dev, MACCSR0, 0x00217223);
        rt2x00pci_register_write(rt2x00dev, MACCSR1, 0x00235518);

        rt2x00pci_register_read(rt2x00dev, MACCSR2, &reg);
        rt2x00_set_field32(&reg, MACCSR2_DELAY, 64);
        rt2x00pci_register_write(rt2x00dev, MACCSR2, reg);

        rt2x00pci_register_read(rt2x00dev, RXCSR3, &reg);
        /*
         * Tx power.
         */
        rt2x00_set_field32(&reg, RXCSR3_BBP_ID0, 3);
        rt2x00_set_field32(&reg, RXCSR3_BBP_ID0_VALID, 1);
        /*
         * Signal.
         */
        rt2x00_set_field32(&reg, RXCSR3_BBP_ID1, 32);
        rt2x00_set_field32(&reg, RXCSR3_BBP_ID1_VALID, 1);
        /*
         * Rssi.
         */
        rt2x00_set_field32(&reg, RXCSR3_BBP_ID2, 36);
        rt2x00_set_field32(&reg, RXCSR3_BBP_ID2_VALID, 1);
        rt2x00pci_register_write(rt2x00dev, RXCSR3, reg);

        rt2x00pci_register_read(rt2x00dev, RALINKCSR, &reg);
        rt2x00_set_field32(&reg, RALINKCSR_AR_BBP_DATA0, 17);
        rt2x00_set_field32(&reg, RALINKCSR_AR_BBP_ID0, 154);
        rt2x00_set_field32(&reg, RALINKCSR_AR_BBP_DATA1, 0);
        rt2x00_set_field32(&reg, RALINKCSR_AR_BBP_ID1, 154);
        rt2x00pci_register_write(rt2x00dev, RALINKCSR, reg);

        rt2x00pci_register_read(rt2x00dev, CSR1, &reg);
        rt2x00_set_field32(&reg, CSR1_SOFT_RESET, 1);
        rt2x00_set_field32(&reg, CSR1_BBP_RESET, 0);
        rt2x00_set_field32(&reg, CSR1_HOST_READY, 0);
        rt2x00pci_register_write(rt2x00dev, CSR1, reg);

        rt2x00pci_register_read(rt2x00dev, CSR1, &reg);
        rt2x00_set_field32(&reg, CSR1_SOFT_RESET, 0);
        rt2x00_set_field32(&reg, CSR1_HOST_READY, 1);
        rt2x00pci_register_write(rt2x00dev, CSR1, reg);

        /*
         * We must clear the FCS and FIFO error count.
         * These registers are cleared on read,
         * so we may pass a useless variable to store the value.
         */
        rt2x00pci_register_read(rt2x00dev, CNT0, &reg);
        rt2x00pci_register_read(rt2x00dev, CNT4, &reg);

        return 0;
}

static int rt2400pci_init_bbp(struct rt2x00_dev *rt2x00dev)
{
        unsigned int i;
        u16 eeprom;
        u8 reg_id;
        u8 value;

        for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
                rt2400pci_bbp_read(rt2x00dev, 0, &value);
                if ((value != 0xff) && (value != 0x00))
                        goto continue_csr_init;
                NOTICE(rt2x00dev, "Waiting for BBP register.\n");
                udelay(REGISTER_BUSY_DELAY);
        }

        ERROR(rt2x00dev, "BBP register access failed, aborting.\n");
        return -EACCES;

continue_csr_init:
        rt2400pci_bbp_write(rt2x00dev, 1, 0x00);
        rt2400pci_bbp_write(rt2x00dev, 3, 0x27);
        rt2400pci_bbp_write(rt2x00dev, 4, 0x08);
        rt2400pci_bbp_write(rt2x00dev, 10, 0x0f);
        rt2400pci_bbp_write(rt2x00dev, 13, 0x08);
        rt2400pci_bbp_write(rt2x00dev, 15, 0x72);
        rt2400pci_bbp_write(rt2x00dev, 16, 0x74);
        rt2400pci_bbp_write(rt2x00dev, 17, 0x20);
        rt2400pci_bbp_write(rt2x00dev, 18, 0x72);
        rt2400pci_bbp_write(rt2x00dev, 19, 0x0b);
        rt2400pci_bbp_write(rt2x00dev, 20, 0x00);
        rt2400pci_bbp_write(rt2x00dev, 28, 0x11);
        rt2400pci_bbp_write(rt2x00dev, 29, 0x04);
        rt2400pci_bbp_write(rt2x00dev, 30, 0x21);
        rt2400pci_bbp_write(rt2x00dev, 31, 0x00);

        DEBUG(rt2x00dev, "Start initialization from EEPROM...\n");
        for (i = 0; i < EEPROM_BBP_SIZE; i++) {
                rt2x00_eeprom_read(rt2x00dev, EEPROM_BBP_START + i, &eeprom);

                if (eeprom != 0xffff && eeprom != 0x0000) {
                        reg_id = rt2x00_get_field16(eeprom, EEPROM_BBP_REG_ID);
                        value = rt2x00_get_field16(eeprom, EEPROM_BBP_VALUE);
                        DEBUG(rt2x00dev, "BBP: 0x%02x, value: 0x%02x.\n",
                                reg_id, value);
                        rt2400pci_bbp_write(rt2x00dev, reg_id, value);
                }
        }
        DEBUG(rt2x00dev, "...End initialization from EEPROM.\n");

        return 0;
}

/*
 * Device state switch handlers.
 */
static void rt2400pci_toggle_rx(struct rt2x00_dev *rt2x00dev,
        enum dev_state state)
{
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, RXCSR0, &reg);
        rt2x00_set_field32(&reg, RXCSR0_DISABLE_RX,
                state == STATE_RADIO_RX_OFF);
        rt2x00pci_register_write(rt2x00dev, RXCSR0, reg);
}

static int rt2400pci_enable_radio(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        /*
         * Initialize all registers.
         */
        if (rt2400pci_init_rings(rt2x00dev) ||
            rt2400pci_init_registers(rt2x00dev) ||
            rt2400pci_init_bbp(rt2x00dev)) {
                ERROR(rt2x00dev, "Register initialization failed.\n");
                return -EIO;
        }

        /*
         * Clear interrupts.
         */
        rt2x00pci_register_read(rt2x00dev, CSR7, &reg);
        rt2x00pci_register_write(rt2x00dev, CSR7, reg);

        /*
         * Enable interrupts.
         */
        rt2x00pci_register_read(rt2x00dev, CSR8, &reg);
        rt2x00_set_field32(&reg, CSR8_TBCN_EXPIRE, 0);
        rt2x00_set_field32(&reg, CSR8_TXDONE_TXRING, 0);
        rt2x00_set_field32(&reg, CSR8_TXDONE_ATIMRING, 0);
        rt2x00_set_field32(&reg, CSR8_TXDONE_PRIORING, 0);
        rt2x00_set_field32(&reg, CSR8_RXDONE, 0);
        rt2x00pci_register_write(rt2x00dev, CSR8, reg);

        /*
         * Enable LED
         */
        rt2400pci_enable_led(rt2x00dev);

        return 0;
}

static void rt2400pci_disable_radio(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;

        /*
         * Disable LED
         */
        rt2400pci_disable_led(rt2x00dev);

        rt2x00pci_register_write(rt2x00dev, PWRCSR0, 0);

        /*
         * Disable synchronisation.
         */
        rt2x00pci_register_write(rt2x00dev, CSR14, 0);

        /*
         * Cancel RX and TX.
         */
        rt2x00pci_register_read(rt2x00dev, TXCSR0, &reg);
        rt2x00_set_field32(&reg, TXCSR0_ABORT, 1);
        rt2x00pci_register_write(rt2x00dev, TXCSR0, reg);

        /*
         * Disable interrupts.
         */
        rt2x00pci_register_read(rt2x00dev, CSR8, &reg);
        rt2x00_set_field32(&reg, CSR8_TBCN_EXPIRE, 1);
        rt2x00_set_field32(&reg, CSR8_TXDONE_TXRING, 1);
        rt2x00_set_field32(&reg, CSR8_TXDONE_ATIMRING, 1);
        rt2x00_set_field32(&reg, CSR8_TXDONE_PRIORING, 1);
        rt2x00_set_field32(&reg, CSR8_RXDONE, 1);
        rt2x00pci_register_write(rt2x00dev, CSR8, reg);
}

static int rt2400pci_set_state(struct rt2x00_dev *rt2x00dev,
        enum dev_state state)
{
        u32 reg;
        unsigned int i;
        char put_to_sleep;
        char bbp_state;
        char rf_state;

        put_to_sleep = (state != STATE_AWAKE);

        rt2x00pci_register_read(rt2x00dev, PWRCSR1, &reg);
        rt2x00_set_field32(&reg, PWRCSR1_SET_STATE, 1);
        rt2x00_set_field32(&reg, PWRCSR1_BBP_DESIRE_STATE, state);
        rt2x00_set_field32(&reg, PWRCSR1_RF_DESIRE_STATE, state);
        rt2x00_set_field32(&reg, PWRCSR1_PUT_TO_SLEEP, put_to_sleep);
        rt2x00pci_register_write(rt2x00dev, PWRCSR1, reg);

        /*
         * Device is not guaranteed to be in the requested state yet.
         * We must wait until the register indicates that the
         * device has entered the correct state.
         */
        for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
                rt2x00pci_register_read(rt2x00dev, PWRCSR1, &reg);
                bbp_state = rt2x00_get_field32(reg, PWRCSR1_BBP_CURR_STATE);
                rf_state = rt2x00_get_field32(reg, PWRCSR1_RF_CURR_STATE);
                if (bbp_state == state && rf_state == state)
                        return 0;
                msleep(10);
        }

        NOTICE(rt2x00dev, "Device failed to enter state %d, "
                "current device state: bbp %d and rf %d.\n",
                state, bbp_state, rf_state);

        return -EBUSY;
}

static int rt2400pci_set_device_state(struct rt2x00_dev *rt2x00dev,
        enum dev_state state)
{
        int retval = 0;

        switch (state) {
                case STATE_RADIO_ON:
                        retval = rt2400pci_enable_radio(rt2x00dev);
                break;
                case STATE_RADIO_OFF:
                        rt2400pci_disable_radio(rt2x00dev);
                break;
                case STATE_RADIO_RX_ON:
                case STATE_RADIO_RX_OFF:
                        rt2400pci_toggle_rx(rt2x00dev, state);
                break;
                case STATE_DEEP_SLEEP:
                case STATE_SLEEP:
                case STATE_STANDBY:
                case STATE_AWAKE:
                        retval = rt2400pci_set_state(rt2x00dev, state);
                break;
                default:
                        retval = -ENOTSUPP;
                break;
        }

        return retval;
}

/*
 * TX descriptor initialization
 */
static void rt2400pci_write_tx_desc(struct rt2x00_dev *rt2x00dev,
        struct data_entry *entry, struct data_desc *txd,
        struct data_entry_desc *desc, struct ieee80211_hdr *ieee80211hdr,
        unsigned int length, struct ieee80211_tx_control *control)
{
        u32 word;
        u32 signal = 0;
        u32 service = 0;
        u32 length_high = 0;
        u32 length_low = 0;

        /*
         * The PLCP values should be treated as if they
         * were BBP values.
         */
        rt2x00_set_field32(&signal, BBPCSR_VALUE, desc->signal);
        rt2x00_set_field32(&signal, BBPCSR_REGNUM, 5);
        rt2x00_set_field32(&signal, BBPCSR_BUSY, 1);

        rt2x00_set_field32(&service, BBPCSR_VALUE, desc->service);
        rt2x00_set_field32(&service, BBPCSR_REGNUM, 6);
        rt2x00_set_field32(&service, BBPCSR_BUSY, 1);

        rt2x00_set_field32(&length_high, BBPCSR_VALUE, desc->length_high);
        rt2x00_set_field32(&length_high, BBPCSR_REGNUM, 7);
        rt2x00_set_field32(&length_high, BBPCSR_BUSY, 1);

        rt2x00_set_field32(&length_low, BBPCSR_VALUE, desc->length_low);
        rt2x00_set_field32(&length_low, BBPCSR_REGNUM, 8);
        rt2x00_set_field32(&length_low, BBPCSR_BUSY, 1);

        /*
         * Start writing the descriptor words.
         */
        rt2x00_desc_read(txd, 2, &word);
        rt2x00_set_field32(&word, TXD_W2_DATABYTE_COUNT, length);
        rt2x00_desc_write(txd, 2, word);

        rt2x00_desc_read(txd, 3, &word);
        rt2x00_set_field32(&word, TXD_W3_PLCP_SIGNAL, signal);
        rt2x00_set_field32(&word, TXD_W3_PLCP_SERVICE, service);
        rt2x00_desc_write(txd, 3, word);

        rt2x00_desc_read(txd, 4, &word);
        rt2x00_set_field32(&word, TXD_W4_PLCP_LENGTH_LOW, length_low);
        rt2x00_set_field32(&word, TXD_W4_PLCP_LENGTH_HIGH, length_high);
        rt2x00_desc_write(txd, 4, word);

        rt2x00_desc_read(txd, 0, &word);
        rt2x00_set_field32(&word, TXD_W0_OWNER_NIC, 1);
        rt2x00_set_field32(&word, TXD_W0_VALID, 1);
        rt2x00_set_field32(&word, TXD_W0_MORE_FRAG,
                test_bit(ENTRY_TXD_MORE_FRAG, &entry->flags));
        rt2x00_set_field32(&word, TXD_W0_ACK,
                test_bit(ENTRY_TXD_REQ_ACK, &entry->flags));
        rt2x00_set_field32(&word, TXD_W0_TIMESTAMP,
                test_bit(ENTRY_TXD_REQ_TIMESTAMP, &entry->flags));
        rt2x00_set_field32(&word, TXD_W0_RTS,
                test_bit(ENTRY_TXD_RTS_FRAME, &entry->flags));
        rt2x00_set_field32(&word, TXD_W0_IFS, desc->ifs);
        rt2x00_set_field32(&word, TXD_W0_RETRY_MODE, 0);
        rt2x00_desc_write(txd, 0, word);
}

/*
 * TX data initialization
 */
static void rt2400pci_kick_tx_queue(struct rt2x00_dev *rt2x00dev, int queue)
{
        u32 reg;

        if (queue == IEEE80211_TX_QUEUE_BEACON) {
                rt2x00pci_register_read(rt2x00dev, CSR14, &reg);
                if (!rt2x00_get_field32(reg, CSR14_BEACON_GEN)) {
                        rt2x00_set_field32(&reg, CSR14_BEACON_GEN, 1);
                        rt2x00pci_register_write(rt2x00dev, CSR14, reg);
                }
                return;
        }

        rt2x00pci_register_read(rt2x00dev, TXCSR0, &reg);
        if (queue == IEEE80211_TX_QUEUE_DATA0)
                rt2x00_set_field32(&reg, TXCSR0_KICK_PRIO, 1);
        else if (queue == IEEE80211_TX_QUEUE_DATA1)
                rt2x00_set_field32(&reg, TXCSR0_KICK_TX, 1);
        else if (queue == IEEE80211_TX_QUEUE_AFTER_BEACON)
                rt2x00_set_field32(&reg, TXCSR0_KICK_ATIM, 1);
        rt2x00pci_register_write(rt2x00dev, TXCSR0, reg);
}

/*
 * Interrupt functions.
 */
static void rt2400pci_rxdone(struct rt2x00_dev *rt2x00dev)
{
        struct data_ring *ring = rt2x00dev->rx;
        struct data_entry *entry;
        struct data_desc *rxd;
        u32 word0;
        u32 word2;
        int signal;
        int rssi;
        u16 size;

        while (1) {
                entry = rt2x00_get_data_entry(ring);
                rxd = entry->priv;
                rt2x00_desc_read(rxd, 0, &word0);
                rt2x00_desc_read(rxd, 2, &word2);

                if (rt2x00_get_field32(word0, RXD_W0_OWNER_NIC))
                        break;

                /*
                 * TODO: Don't we need to keep statistics
                 * updated about events like CRC and physical errors?
                 */
                if (rt2x00_get_field32(word0, RXD_W0_CRC) ||
                    rt2x00_get_field32(word0, RXD_W0_PHYSICAL_ERROR))
                        goto skip_entry;

                /*
                 * Obtain the status about this packet.
                 */
                size = rt2x00_get_field32(word0, RXD_W0_DATABYTE_COUNT);
                signal = rt2x00_get_field32(word2, RXD_W2_SIGNAL);
                rssi = rt2x00_get_field32(word2, RXD_W2_RSSI);

                /*
                 * Send the packet to upper layer.
                 */
                rt2x00lib_rxdone(entry, entry->data_addr, size,
                        signal, rssi, 0);

skip_entry:
                if (test_bit(DEVICE_ENABLED_RADIO, &ring->rt2x00dev->flags)) {
                        rt2x00_set_field32(&word0, RXD_W0_OWNER_NIC, 1);
                        rt2x00_desc_write(rxd, 0, word0);
                }

                rt2x00_ring_index_inc(ring);
        }
}

static void rt2400pci_txdone(struct rt2x00_dev *rt2x00dev, const int queue)
{
        struct data_ring *ring = rt2x00_get_ring(rt2x00dev, queue);
        struct data_entry *entry;
        struct data_desc *txd;
        u32 word;
        int tx_status;
        int retry;

        while (!rt2x00_ring_empty(ring)) {
                entry = rt2x00_get_data_entry_done(ring);
                txd = entry->priv;
                rt2x00_desc_read(txd, 0, &word);

                if (rt2x00_get_field32(word, TXD_W0_OWNER_NIC) ||
                    !rt2x00_get_field32(word, TXD_W0_VALID))
                        break;

                /*
                 * Obtain the status about this packet.
                 */
                tx_status = rt2x00_get_field32(word, TXD_W0_RESULT);
                retry = rt2x00_get_field32(word, TXD_W0_RETRY_COUNT);

                rt2x00lib_txdone(entry, tx_status, retry);

                /*
                 * Make this entry available for reuse.
                 */
                entry->flags = 0;
                rt2x00_set_field32(&word, TXD_W0_VALID, 0);
                rt2x00_desc_write(txd, 0, word);
                rt2x00_ring_index_done_inc(ring);
        }

        /*
         * If the data ring was full before the txdone handler
         * we must make sure the packet queue in the mac80211 stack
         * is reenabled when the txdone handler has finished.
         */
        entry = ring->entry;
        if (!rt2x00_ring_full(ring))
                ieee80211_wake_queue(rt2x00dev->hw,
                        entry->tx_status.control.queue);
}

static irqreturn_t rt2400pci_interrupt(int irq, void *dev_instance)
{
        struct rt2x00_dev *rt2x00dev = dev_instance;
        u32 reg;

        /*
         * Get the interrupt sources & saved to local variable.
         * Write register value back to clear pending interrupts.
         */
        rt2x00pci_register_read(rt2x00dev, CSR7, &reg);
        rt2x00pci_register_write(rt2x00dev, CSR7, reg);

        if (!reg)
                return IRQ_NONE;

        if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
                return IRQ_HANDLED;

        /*
         * Handle interrupts, walk through all bits
         * and run the tasks, the bits are checked in order of
         * priority.
         */

        /*
         * 1 - Beacon timer expired interrupt.
         */
        if (rt2x00_get_field32(reg, CSR7_TBCN_EXPIRE))
                rt2x00pci_beacondone(rt2x00dev, IEEE80211_TX_QUEUE_BEACON);

        /*
         * 2 - Rx ring done interrupt.
         */
        if (rt2x00_get_field32(reg, CSR7_RXDONE))
                rt2400pci_rxdone(rt2x00dev);

        /*
         * 3 - Atim ring transmit done interrupt.
         */
        if (rt2x00_get_field32(reg, CSR7_TXDONE_ATIMRING))
                rt2400pci_txdone(rt2x00dev, IEEE80211_TX_QUEUE_AFTER_BEACON);

        /*
         * 4 - Priority ring transmit done interrupt.
         */
        if (rt2x00_get_field32(reg, CSR7_TXDONE_PRIORING))
                rt2400pci_txdone(rt2x00dev, IEEE80211_TX_QUEUE_DATA0);

        /*
         * 5 - Tx ring transmit done interrupt.
         */
        if (rt2x00_get_field32(reg, CSR7_TXDONE_TXRING))
                rt2400pci_txdone(rt2x00dev, IEEE80211_TX_QUEUE_DATA1);

        return IRQ_HANDLED;
}

/*
 * Device initialization functions.
 */
static int rt2400pci_alloc_eeprom(struct rt2x00_dev *rt2x00dev)
{
        struct eeprom_93cx6 eeprom;
        u32 reg;
        u16 word;

        /*
         * Allocate the eeprom memory, check the eeprom width
         * and copy the entire eeprom into this allocated memory.
         */
        rt2x00dev->eeprom = kzalloc(EEPROM_SIZE, GFP_KERNEL);
        if (!rt2x00dev->eeprom)
                return -ENOMEM;

        rt2x00pci_register_read(rt2x00dev, CSR21, &reg);

        eeprom.data = rt2x00dev;
        eeprom.register_read = rt2400pci_eepromregister_read;
        eeprom.register_write = rt2400pci_eepromregister_write;
        eeprom.width = rt2x00_get_field32(reg, CSR21_TYPE_93C46) ?
                PCI_EEPROM_WIDTH_93C46 : PCI_EEPROM_WIDTH_93C66;
        eeprom.reg_data_in = 0;
        eeprom.reg_data_out = 0;
        eeprom.reg_data_clock = 0;
        eeprom.reg_chip_select = 0;

        eeprom_93cx6_multiread(&eeprom, EEPROM_BASE, rt2x00dev->eeprom,
                EEPROM_SIZE / sizeof(u16));

        /*
         * Start validation of the data that has been read.
         */
        rt2x00_eeprom_read(rt2x00dev, EEPROM_ANTENNA, &word);
        if (word == 0xffff) {
                ERROR(rt2x00dev, "Invalid EEPROM data detected.\n");
                return -EINVAL;
        }

        return 0;
}

static int rt2400pci_init_eeprom(struct rt2x00_dev *rt2x00dev)
{
        u32 reg;
        u16 value;
        u16 eeprom;

        /*
         * Read EEPROM word for configuration.
         */
        rt2x00_eeprom_read(rt2x00dev, EEPROM_ANTENNA, &eeprom);

        /*
         * Identify RF chipset.
         */
        value = rt2x00_get_field16(eeprom, EEPROM_ANTENNA_RF_TYPE);
        rt2x00pci_register_read(rt2x00dev, CSR0, &reg);
        rt2x00_set_chip(rt2x00dev, RT2460, value, reg);

        if (!rt2x00_rf(&rt2x00dev->chip, RF2420) &&
            !rt2x00_rf(&rt2x00dev->chip, RF2421)) {
                ERROR(rt2x00dev, "Invalid RF chipset detected.\n");
                return -ENODEV;
        }

        /*
         * Identify default antenna configuration.
         */
        rt2x00dev->hw->conf.antenna_sel_tx = rt2x00_get_field16(eeprom,
                EEPROM_ANTENNA_TX_DEFAULT);
        rt2x00dev->hw->conf.antenna_sel_rx = rt2x00_get_field16(eeprom,
                EEPROM_ANTENNA_RX_DEFAULT);

        /*
         * Store led mode, for correct led behaviour.
         */
        rt2x00dev->led_mode = rt2x00_get_field16(eeprom,
                EEPROM_ANTENNA_LED_MODE);

        /*
         * Detect if this device has an hardware controlled radio.
         */
        if (rt2x00_get_field16(eeprom, EEPROM_ANTENNA_HARDWARE_RADIO))
                __set_bit(DEVICE_SUPPORT_HW_BUTTON, &rt2x00dev->flags);

        /*
         * Check if the BBP tuning should be enabled.
         */
        if (!rt2x00_get_field16(eeprom, EEPROM_ANTENNA_RX_AGCVGC_TUNING))
                __set_bit(CONFIG_DISABLE_LINK_TUNING, &rt2x00dev->flags);

        return 0;
}

/*
 * RF value list for RF2420 & RF2421
 * Supports: 2.4 GHz
 */
static const u32 rf_vals_bg[] = {
        0x000c1fda, 0x000c1fee, 0x000c2002, 0x000c2016, 0x000c202a,
        0x000c203e, 0x000c2052, 0x000c2066, 0x000c207a, 0x000c208e,
        0x000c20a2, 0x000c20b6, 0x000c20ca, 0x000c20fa
};

static void rt2400pci_init_hw_mode(struct rt2x00_dev *rt2x00dev)
{
        struct hw_mode_spec *spec = &rt2x00dev->spec;
        u8 *txpower;
        unsigned int i;

        /*
         * Initialize all hw fields.
         */
        rt2x00dev->hw->flags = IEEE80211_HW_HOST_GEN_BEACON |
                IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING |
                IEEE80211_HW_WEP_INCLUDE_IV |
                IEEE80211_HW_DATA_NULLFUNC_ACK |
                IEEE80211_HW_NO_TKIP_WMM_HWACCEL |
                IEEE80211_HW_MONITOR_DURING_OPER;
        rt2x00dev->hw->extra_tx_headroom = 0;
        rt2x00dev->hw->max_rssi = MAX_RX_SSI;
        rt2x00dev->hw->max_noise = MAX_RX_NOISE;
        rt2x00dev->hw->queues = 2;

        /*
         * This device supports ATIM
         */
        __set_bit(DEVICE_SUPPORT_ATIM, &rt2x00dev->flags);

        /*
         * Set device specific, but channel independent RF values.
         */
        rt2x00dev->rf1 = 0x00022058;
        if (rt2x00_rf(&rt2x00dev->chip, RF2420))
                rt2x00dev->rf3 = 0x00000111;
        else
                rt2x00dev->rf3 = 0x00000101;

        /*
         * Convert tx_power array in eeprom.
         */
        txpower = rt2x00_eeprom_addr(rt2x00dev, EEPROM_TXPOWER_START);
        for (i = 0; i < 14; i++)
                txpower[i] = TXPOWER_FROM_DEV(txpower[i]);

        /*
         * Initialize hw_mode information.
         */
        spec->mac_addr = rt2x00_eeprom_addr(rt2x00dev, EEPROM_MAC_ADDR_0);
        spec->num_modes = 1;
        spec->num_rates = 4;
        spec->num_channels = 14;
        spec->tx_power_a = NULL;
        spec->tx_power_bg = txpower;
        spec->tx_power_default = DEFAULT_TXPOWER;
        spec->chan_val_a = NULL;
        spec->chan_val_bg = rf_vals_bg;
}

static int rt2400pci_init_hw(struct rt2x00_dev *rt2x00dev)
{
        int retval;

        /*
         * Allocate eeprom data.
         */
        retval = rt2400pci_alloc_eeprom(rt2x00dev);
        if (retval)
                return retval;

        retval = rt2400pci_init_eeprom(rt2x00dev);
        if (retval)
                return retval;

        /*
         * Initialize hw specifications.
         */
        rt2400pci_init_hw_mode(rt2x00dev);

        return 0;
}

/*
 * IEEE80211 stack callback functions.
 */
static int rt2400pci_get_stats(struct ieee80211_hw *hw,
        struct ieee80211_low_level_stats *stats)
{
        struct rt2x00_dev *rt2x00dev = hw->priv;
        u32 reg;

        /*
         * Update FCS error count from register.
         * The dot11ACKFailureCount, dot11RTSFailureCount and
         * dot11RTSSuccessCount are updated in interrupt time.
         */
        rt2x00pci_register_read(rt2x00dev, CNT0, &reg);
        rt2x00dev->low_level_stats.dot11FCSErrorCount +=
                rt2x00_get_field32(reg, CNT0_FCS_ERROR);

        memcpy(stats, &rt2x00dev->low_level_stats, sizeof(*stats));

        return 0;
}

static int rt2400pci_set_retry_limit(struct ieee80211_hw *hw,
        u32 short_retry, u32 long_retry)
{
        struct rt2x00_dev *rt2x00dev = hw->priv;
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, CSR11, &reg);
        rt2x00_set_field32(&reg, CSR11_LONG_RETRY, long_retry);
        rt2x00_set_field32(&reg, CSR11_SHORT_RETRY, short_retry);
        rt2x00pci_register_write(rt2x00dev, CSR11, reg);

        return 0;
}

static int rt2400pci_conf_tx(struct ieee80211_hw *hw,
        int queue, const struct ieee80211_tx_queue_params *params)
{
        struct rt2x00_dev *rt2x00dev = hw->priv;

        /*
         * We don't support variating cw_min and cw_max variables
         * per queue. So by default we only configure the TX queue,
         * and ignore all other configurations.
         */
        if (queue != IEEE80211_TX_QUEUE_DATA0)
                return -EINVAL;

        if (rt2x00lib_conf_tx(hw, queue, params))
                return -EINVAL;

        /*
         * Write configuration to register.
         */
        rt2400pci_config_cw(rt2x00dev, &rt2x00dev->tx->tx_params);

        return 0;
}

static u64 rt2400pci_get_tsf(struct ieee80211_hw *hw)
{
        struct rt2x00_dev *rt2x00dev = hw->priv;
        u64 tsf;
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, CSR17, &reg);
        tsf = (u64)rt2x00_get_field32(reg, CSR17_HIGH_TSFTIMER) << 32;
        rt2x00pci_register_read(rt2x00dev, CSR16, &reg);
        tsf |= rt2x00_get_field32(reg, CSR16_LOW_TSFTIMER);

        return tsf;
}

static void rt2400pci_reset_tsf(struct ieee80211_hw *hw)
{
        struct rt2x00_dev *rt2x00dev = hw->priv;

        rt2x00pci_register_write(rt2x00dev, CSR16, 0);
        rt2x00pci_register_write(rt2x00dev, CSR17, 0);
}

static int rt2400pci_tx_last_beacon(struct ieee80211_hw *hw)
{
        struct rt2x00_dev *rt2x00dev = hw->priv;
        u32 reg;

        rt2x00pci_register_read(rt2x00dev, CSR15, &reg);
        return rt2x00_get_field32(reg, CSR15_BEACON_SENT);
}

static const struct ieee80211_ops rt2400pci_mac80211_ops = {
        .tx                     = rt2x00lib_tx,
        .reset                  = rt2x00lib_reset,
        .open                   = rt2x00lib_open,
        .stop                   = rt2x00lib_stop,
        .add_interface          = rt2x00lib_add_interface,
        .remove_interface       = rt2x00lib_remove_interface,
        .config                 = rt2x00lib_config,
        .config_interface       = rt2x00lib_config_interface,
        .set_multicast_list     = rt2x00lib_set_multicast_list,
        .get_stats              = rt2400pci_get_stats,
        .set_retry_limit        = rt2400pci_set_retry_limit,
        .conf_tx                = rt2400pci_conf_tx,
        .get_tx_stats           = rt2x00lib_get_tx_stats,
        .get_tsf                = rt2400pci_get_tsf,
        .reset_tsf              = rt2400pci_reset_tsf,
        .beacon_update          = rt2x00pci_beacon_update,
        .tx_last_beacon         = rt2400pci_tx_last_beacon,
};

static const struct rt2x00lib_ops rt2400pci_rt2x00_ops = {
        .irq_handler            = rt2400pci_interrupt,
        .init_hw                = rt2400pci_init_hw,
        .initialize             = rt2x00pci_initialize,
        .uninitialize           = rt2x00pci_uninitialize,
        .set_device_state       = rt2400pci_set_device_state,
#ifdef CONFIG_RT2400PCI_RFKILL
        .rfkill_poll            = rt2400pci_rfkill_poll,
#endif /* CONFIG_RT2400PCI_RFKILL */
        .link_tuner             = rt2400pci_link_tuner,
        .write_tx_desc          = rt2400pci_write_tx_desc,
        .write_tx_data          = rt2x00pci_write_tx_data,
        .kick_tx_queue          = rt2400pci_kick_tx_queue,
        .config_type            = rt2400pci_config_type,
        .config_phymode         = rt2400pci_config_phymode,
        .config_channel         = rt2400pci_config_channel,
        .config_mac_addr        = rt2400pci_config_mac_addr,
        .config_bssid           = rt2400pci_config_bssid,
        .config_promisc         = rt2400pci_config_promisc,
        .config_txpower         = rt2400pci_config_txpower,
        .config_antenna         = rt2400pci_config_antenna,
        .config_duration        = rt2400pci_config_duration,
};

static const struct rt2x00_ops rt2400pci_ops = {
        .name   = DRV_NAME,
        .rxd_size = RXD_DESC_SIZE,
        .txd_size = TXD_DESC_SIZE,
        .lib    = &rt2400pci_rt2x00_ops,
        .hw     = &rt2400pci_mac80211_ops,
#ifdef CONFIG_RT2X00_LIB_DEBUGFS
        .debugfs = &rt2400pci_rt2x00debug,
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */
};

/*
 * RT2400pci module information.
 */
static struct pci_device_id rt2400pci_device_table[] = {
        { PCI_DEVICE(0x1814, 0x0101), PCI_DEVICE_DATA(&rt2400pci_ops) },
        { 0, }
};

MODULE_AUTHOR(DRV_PROJECT);
MODULE_VERSION(DRV_VERSION);
MODULE_DESCRIPTION("Ralink RT2400 PCI & PCMCIA Wireless LAN driver.");
MODULE_SUPPORTED_DEVICE("Ralink RT2460 PCI & PCMCIA chipset based cards");
MODULE_DEVICE_TABLE(pci, rt2400pci_device_table);
MODULE_LICENSE("GPL");

static struct pci_driver rt2400pci_driver = {
        .name           = DRV_NAME,
        .id_table       = rt2400pci_device_table,
        .probe          = rt2x00pci_probe,
        .remove         = __devexit_p(rt2x00pci_remove),
#ifdef CONFIG_PM
        .suspend        = rt2x00pci_suspend,
        .resume         = rt2x00pci_resume,
#endif /* CONFIG_PM */
};

static int __init rt2400pci_init(void)
{
        printk(KERN_INFO "Loading module: %s - %s by %s.\n",
                DRV_NAME, DRV_VERSION, DRV_PROJECT);
        return pci_register_driver(&rt2400pci_driver);
}

static void __exit rt2400pci_exit(void)
{
        printk(KERN_INFO "Unloading module: %s.\n", DRV_NAME);
        pci_unregister_driver(&rt2400pci_driver);
}

module_init(rt2400pci_init);
module_exit(rt2400pci_exit);