rt73usb.c

/*
	Copyright (C) 2004 - 2008 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: rt73usb
	Abstract: rt73usb device specific routines.
	Supported chipsets: rt2571W & rt2671.
 */

#include <linux/crc-itu-t.h>
#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb.h>

#include "rt2x00.h"
#include "rt2x00usb.h"
#include "rt73usb.h"

/*
 * Allow hardware encryption to be disabled.
 */
static int modparam_nohwcrypt = 0;
module_param_named(nohwcrypt, modparam_nohwcrypt, bool, S_IRUGO);
MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");

/*
 * Register access.
 * All access to the CSR registers will go through the methods
 * rt73usb_register_read and rt73usb_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.
 * The _lock versions must be used if you already hold the csr_mutex
 */
static inline void rt73usb_register_read(struct rt2x00_dev *rt2x00dev,
					 const unsigned int offset, u32 *value)
{
	__le32 reg;
	rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
				      USB_VENDOR_REQUEST_IN, offset,
				      &reg, sizeof(reg), REGISTER_TIMEOUT);
	*value = le32_to_cpu(reg);
}

static inline void rt73usb_register_read_lock(struct rt2x00_dev *rt2x00dev,
					      const unsigned int offset, u32 *value)
{
	__le32 reg;
	rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_READ,
				       USB_VENDOR_REQUEST_IN, offset,
				       &reg, sizeof(reg), REGISTER_TIMEOUT);
	*value = le32_to_cpu(reg);
}

static inline void rt73usb_register_multiread(struct rt2x00_dev *rt2x00dev,
					      const unsigned int offset,
					      void *value, const u32 length)
{
	rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ,
				      USB_VENDOR_REQUEST_IN, offset,
				      value, length,
				      REGISTER_TIMEOUT32(length));
}

static inline void rt73usb_register_write(struct rt2x00_dev *rt2x00dev,
					  const unsigned int offset, u32 value)
{
	__le32 reg = cpu_to_le32(value);
	rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_WRITE,
				      USB_VENDOR_REQUEST_OUT, offset,
				      &reg, sizeof(reg), REGISTER_TIMEOUT);
}

static inline void rt73usb_register_write_lock(struct rt2x00_dev *rt2x00dev,
					       const unsigned int offset, u32 value)
{
	__le32 reg = cpu_to_le32(value);
	rt2x00usb_vendor_req_buff_lock(rt2x00dev, USB_MULTI_WRITE,
				       USB_VENDOR_REQUEST_OUT, offset,
				       &reg, sizeof(reg), REGISTER_TIMEOUT);
}

static inline void rt73usb_register_multiwrite(struct rt2x00_dev *rt2x00dev,
					       const unsigned int offset,
					       void *value, const u32 length)
{
	rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_WRITE,
				      USB_VENDOR_REQUEST_OUT, offset,
				      value, length,
				      REGISTER_TIMEOUT32(length));
}

static int rt73usb_regbusy_read(struct rt2x00_dev *rt2x00dev,
				const unsigned int offset,
				struct rt2x00_field32 field,
				u32 *reg)
{
	unsigned int i;

	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
		rt73usb_register_read_lock(rt2x00dev, offset, reg);
		if (!rt2x00_get_field32(*reg, field))
			return 1;
		udelay(REGISTER_BUSY_DELAY);
	}

	ERROR(rt2x00dev, "Indirect register access failed: "
	      "offset=0x%.08x, value=0x%.08x\n", offset, *reg);
	*reg = ~0;

	return 0;
}

#define WAIT_FOR_BBP(__dev, __reg) \
	rt73usb_regbusy_read((__dev), PHY_CSR3, PHY_CSR3_BUSY, (__reg))
#define WAIT_FOR_RF(__dev, __reg) \
	rt73usb_regbusy_read((__dev), PHY_CSR4, PHY_CSR4_BUSY, (__reg))

static void rt73usb_bbp_write(struct rt2x00_dev *rt2x00dev,
			      const unsigned int word, const u8 value)
{
	u32 reg;

	mutex_lock(&rt2x00dev->csr_mutex);

	/*
	 * Wait until the BBP becomes available, afterwards we
	 * can safely write the new data into the register.
	 */
	if (WAIT_FOR_BBP(rt2x00dev, &reg)) {
		reg = 0;
		rt2x00_set_field32(&reg, PHY_CSR3_VALUE, value);
		rt2x00_set_field32(&reg, PHY_CSR3_REGNUM, word);
		rt2x00_set_field32(&reg, PHY_CSR3_BUSY, 1);
		rt2x00_set_field32(&reg, PHY_CSR3_READ_CONTROL, 0);

		rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);
	}

	mutex_unlock(&rt2x00dev->csr_mutex);
}

static void rt73usb_bbp_read(struct rt2x00_dev *rt2x00dev,
			     const unsigned int word, u8 *value)
{
	u32 reg;

	mutex_lock(&rt2x00dev->csr_mutex);

	/*
	 * Wait until the BBP becomes available, afterwards we
	 * can safely write the read request into the register.
	 * After the data has been written, we wait until hardware
	 * returns the correct value, if at any time the register
	 * doesn't become available in time, reg will be 0xffffffff
	 * which means we return 0xff to the caller.
	 */
	if (WAIT_FOR_BBP(rt2x00dev, &reg)) {
		reg = 0;
		rt2x00_set_field32(&reg, PHY_CSR3_REGNUM, word);
		rt2x00_set_field32(&reg, PHY_CSR3_BUSY, 1);
		rt2x00_set_field32(&reg, PHY_CSR3_READ_CONTROL, 1);

		rt73usb_register_write_lock(rt2x00dev, PHY_CSR3, reg);

		WAIT_FOR_BBP(rt2x00dev, &reg);
	}

	*value = rt2x00_get_field32(reg, PHY_CSR3_VALUE);

	mutex_unlock(&rt2x00dev->csr_mutex);
}

static void rt73usb_rf_write(struct rt2x00_dev *rt2x00dev,
			     const unsigned int word, const u32 value)
{
	u32 reg;

	if (!word)
		return;

	mutex_lock(&rt2x00dev->csr_mutex);

	/*
	 * Wait until the RF becomes available, afterwards we
	 * can safely write the new data into the register.
	 */
	if (WAIT_FOR_RF(rt2x00dev, &reg)) {
		reg = 0;
		rt2x00_set_field32(&reg, PHY_CSR4_VALUE, value);
		/*
		 * RF5225 and RF2527 contain 21 bits per RF register value,
		 * all others contain 20 bits.
		 */
		rt2x00_set_field32(&reg, PHY_CSR4_NUMBER_OF_BITS,
				   20 + (rt2x00_rf(&rt2x00dev->chip, RF5225) ||
					 rt2x00_rf(&rt2x00dev->chip, RF2527)));
		rt2x00_set_field32(&reg, PHY_CSR4_IF_SELECT, 0);
		rt2x00_set_field32(&reg, PHY_CSR4_BUSY, 1);

		rt73usb_register_write_lock(rt2x00dev, PHY_CSR4, reg);
		rt2x00_rf_write(rt2x00dev, word, value);
	}

	mutex_unlock(&rt2x00dev->csr_mutex);
}

#ifdef CONFIG_RT2X00_LIB_DEBUGFS
static const struct rt2x00debug rt73usb_rt2x00debug = {
	.owner	= THIS_MODULE,
	.csr	= {
		.read		= rt73usb_register_read,
		.write		= rt73usb_register_write,
		.flags		= RT2X00DEBUGFS_OFFSET,
		.word_base	= CSR_REG_BASE,
		.word_size	= sizeof(u32),
		.word_count	= CSR_REG_SIZE / sizeof(u32),
	},
	.eeprom	= {
		.read		= rt2x00_eeprom_read,
		.write		= rt2x00_eeprom_write,
		.word_base	= EEPROM_BASE,
		.word_size	= sizeof(u16),
		.word_count	= EEPROM_SIZE / sizeof(u16),
	},
	.bbp	= {
		.read		= rt73usb_bbp_read,
		.write		= rt73usb_bbp_write,
		.word_base	= BBP_BASE,
		.word_size	= sizeof(u8),
		.word_count	= BBP_SIZE / sizeof(u8),
	},
	.rf	= {
		.read		= rt2x00_rf_read,
		.write		= rt73usb_rf_write,
		.word_base	= RF_BASE,
		.word_size	= sizeof(u32),
		.word_count	= RF_SIZE / sizeof(u32),
	},
};
#endif /* CONFIG_RT2X00_LIB_DEBUGFS */

#ifdef CONFIG_RT2X00_LIB_LEDS
static void rt73usb_brightness_set(struct led_classdev *led_cdev,
				   enum led_brightness brightness)
{
	struct rt2x00_led *led =
	   container_of(led_cdev, struct rt2x00_led, led_dev);
	unsigned int enabled = brightness != LED_OFF;
	unsigned int a_mode =
	    (enabled && led->rt2x00dev->curr_band == IEEE80211_BAND_5GHZ);
	unsigned int bg_mode =
	    (enabled && led->rt2x00dev->curr_band == IEEE80211_BAND_2GHZ);

	if (led->type == LED_TYPE_RADIO) {
		rt2x00_set_field16(&led->rt2x00dev->led_mcu_reg,
				   MCU_LEDCS_RADIO_STATUS, enabled);

		rt2x00usb_vendor_request_sw(led->rt2x00dev, USB_LED_CONTROL,
					    0, led->rt2x00dev->led_mcu_reg,
					    REGISTER_TIMEOUT);
	} else if (led->type == LED_TYPE_ASSOC) {
		rt2x00_set_field16(&led->rt2x00dev->led_mcu_reg,
				   MCU_LEDCS_LINK_BG_STATUS, bg_mode);
		rt2x00_set_field16(&led->rt2x00dev->led_mcu_reg,
				   MCU_LEDCS_LINK_A_STATUS, a_mode);

		rt2x00usb_vendor_request_sw(led->rt2x00dev, USB_LED_CONTROL,
					    0, led->rt2x00dev->led_mcu_reg,
					    REGISTER_TIMEOUT);
	} else if (led->type == LED_TYPE_QUALITY) {
		/*
		 * The brightness is divided into 6 levels (0 - 5),
		 * this means we need to convert the brightness
		 * argument into the matching level within that range.
		 */
		rt2x00usb_vendor_request_sw(led->rt2x00dev, USB_LED_CONTROL,
					    brightness / (LED_FULL / 6),
					    led->rt2x00dev->led_mcu_reg,
					    REGISTER_TIMEOUT);
	}
}

static int rt73usb_blink_set(struct led_classdev *led_cdev,
			     unsigned long *delay_on,
			     unsigned long *delay_off)
{
	struct rt2x00_led *led =
	    container_of(led_cdev, struct rt2x00_led, led_dev);
	u32 reg;

	rt73usb_register_read(led->rt2x00dev, MAC_CSR14, &reg);
	rt2x00_set_field32(&reg, MAC_CSR14_ON_PERIOD, *delay_on);
	rt2x00_set_field32(&reg, MAC_CSR14_OFF_PERIOD, *delay_off);
	rt73usb_register_write(led->rt2x00dev, MAC_CSR14, reg);

	return 0;
}

static void rt73usb_init_led(struct rt2x00_dev *rt2x00dev,
			     struct rt2x00_led *led,
			     enum led_type type)
{
	led->rt2x00dev = rt2x00dev;
	led->type = type;
	led->led_dev.brightness_set = rt73usb_brightness_set;
	led->led_dev.blink_set = rt73usb_blink_set;
	led->flags = LED_INITIALIZED;
}
#endif /* CONFIG_RT2X00_LIB_LEDS */

/*
 * Configuration handlers.
 */
static int rt73usb_config_shared_key(struct rt2x00_dev *rt2x00dev,
				     struct rt2x00lib_crypto *crypto,
				     struct ieee80211_key_conf *key)
{
	struct hw_key_entry key_entry;
	struct rt2x00_field32 field;
	int timeout;
	u32 mask;
	u32 reg;

	if (crypto->cmd == SET_KEY) {
		/*
		 * rt2x00lib can't determine the correct free
		 * key_idx for shared keys. We have 1 register
		 * with key valid bits. The goal is simple, read
		 * the register, if that is full we have no slots
		 * left.
		 * Note that each BSS is allowed to have up to 4
		 * shared keys, so put a mask over the allowed
		 * entries.
		 */
		mask = (0xf << crypto->bssidx);

		rt73usb_register_read(rt2x00dev, SEC_CSR0, &reg);
		reg &= mask;

		if (reg && reg == mask)
			return -ENOSPC;

		key->hw_key_idx += reg ? ffz(reg) : 0;

		/*
		 * Upload key to hardware
		 */
		memcpy(key_entry.key, crypto->key,
		       sizeof(key_entry.key));
		memcpy(key_entry.tx_mic, crypto->tx_mic,
		       sizeof(key_entry.tx_mic));
		memcpy(key_entry.rx_mic, crypto->rx_mic,
		       sizeof(key_entry.rx_mic));

		reg = SHARED_KEY_ENTRY(key->hw_key_idx);
		timeout = REGISTER_TIMEOUT32(sizeof(key_entry));
		rt2x00usb_vendor_request_large_buff(rt2x00dev, USB_MULTI_WRITE,
						    USB_VENDOR_REQUEST_OUT, reg,
						    &key_entry,
						    sizeof(key_entry),
						    timeout);

		/*
		 * The cipher types are stored over 2 registers.
		 * bssidx 0 and 1 keys are stored in SEC_CSR1 and
		 * bssidx 1 and 2 keys are stored in SEC_CSR5.
		 * Using the correct defines correctly will cause overhead,
		 * so just calculate the correct offset.
		 */
		if (key->hw_key_idx < 8) {
			field.bit_offset = (3 * key->hw_key_idx);
			field.bit_mask = 0x7 << field.bit_offset;

			rt73usb_register_read(rt2x00dev, SEC_CSR1, &reg);
			rt2x00_set_field32(&reg, field, crypto->cipher);
			rt73usb_register_write(rt2x00dev, SEC_CSR1, reg);
		} else {
			field.bit_offset = (3 * (key->hw_key_idx - 8));
			field.bit_mask = 0x7 << field.bit_offset;

			rt73usb_register_read(rt2x00dev, SEC_CSR5, &reg);
			rt2x00_set_field32(&reg, field, crypto->cipher);
			rt73usb_register_write(rt2x00dev, SEC_CSR5, reg);
		}

		/*
		 * The driver does not support the IV/EIV generation
		 * in hardware. However it doesn't support the IV/EIV
		 * inside the ieee80211 frame either, but requires it
		 * to be provided seperately for the descriptor.
		 * rt2x00lib will cut the IV/EIV data out of all frames
		 * given to us by mac80211, but we must tell mac80211
		 * to generate the IV/EIV data.
		 */
		key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
	}

	/*
	 * SEC_CSR0 contains only single-bit fields to indicate
	 * a particular key is valid. Because using the FIELD32()
	 * defines directly will cause a lot of overhead we use
	 * a calculation to determine the correct bit directly.
	 */
	mask = 1 << key->hw_key_idx;

	rt73usb_register_read(rt2x00dev, SEC_CSR0, &reg);
	if (crypto->cmd == SET_KEY)
		reg |= mask;
	else if (crypto->cmd == DISABLE_KEY)
		reg &= ~mask;
	rt73usb_register_write(rt2x00dev, SEC_CSR0, reg);

	return 0;
}

static int rt73usb_config_pairwise_key(struct rt2x00_dev *rt2x00dev,
				       struct rt2x00lib_crypto *crypto,
				       struct ieee80211_key_conf *key)
{
	struct hw_pairwise_ta_entry addr_entry;
	struct hw_key_entry key_entry;
	int timeout;
	u32 mask;
	u32 reg;

	if (crypto->cmd == SET_KEY) {
		/*
		 * rt2x00lib can't determine the correct free
		 * key_idx for pairwise keys. We have 2 registers
		 * with key valid bits. The goal is simple, read
		 * the first register, if that is full move to
		 * the next register.
		 * When both registers are full, we drop the key,
		 * otherwise we use the first invalid entry.
		 */
		rt73usb_register_read(rt2x00dev, SEC_CSR2, &reg);
		if (reg && reg == ~0) {
			key->hw_key_idx = 32;
			rt73usb_register_read(rt2x00dev, SEC_CSR3, &reg);
			if (reg && reg == ~0)
				return -ENOSPC;
		}

		key->hw_key_idx += reg ? ffz(reg) : 0;

		/*
		 * Upload key to hardware
		 */
		memcpy(key_entry.key, crypto->key,
		       sizeof(key_entry.key));
		memcpy(key_entry.tx_mic, crypto->tx_mic,
		       sizeof(key_entry.tx_mic));
		memcpy(key_entry.rx_mic, crypto->rx_mic,
		       sizeof(key_entry.rx_mic));

		reg = PAIRWISE_KEY_ENTRY(key->hw_key_idx);
		timeout = REGISTER_TIMEOUT32(sizeof(key_entry));
		rt2x00usb_vendor_request_large_buff(rt2x00dev, USB_MULTI_WRITE,
						    USB_VENDOR_REQUEST_OUT, reg,
						    &key_entry,
						    sizeof(key_entry),
						    timeout);

		/*
		 * Send the address and cipher type to the hardware register.
		 * This data fits within the CSR cache size, so we can use
		 * rt73usb_register_multiwrite() directly.
		 */
		memset(&addr_entry, 0, sizeof(addr_entry));
		memcpy(&addr_entry, crypto->address, ETH_ALEN);
		addr_entry.cipher = crypto->cipher;

		reg = PAIRWISE_TA_ENTRY(key->hw_key_idx);
		rt73usb_register_multiwrite(rt2x00dev, reg,
					    &addr_entry, sizeof(addr_entry));

		/*
		 * Enable pairwise lookup table for given BSS idx,
		 * without this received frames will not be decrypted
		 * by the hardware.
		 */
		rt73usb_register_read(rt2x00dev, SEC_CSR4, &reg);
		reg |= (1 << crypto->bssidx);
		rt73usb_register_write(rt2x00dev, SEC_CSR4, reg);

		/*
		 * The driver does not support the IV/EIV generation
		 * in hardware. However it doesn't support the IV/EIV
		 * inside the ieee80211 frame either, but requires it
		 * to be provided seperately for the descriptor.
		 * rt2x00lib will cut the IV/EIV data out of all frames
		 * given to us by mac80211, but we must tell mac80211
		 * to generate the IV/EIV data.
		 */
		key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
	}

	/*
	 * SEC_CSR2 and SEC_CSR3 contain only single-bit fields to indicate
	 * a particular key is valid. Because using the FIELD32()
	 * defines directly will cause a lot of overhead we use
	 * a calculation to determine the correct bit directly.
	 */
	if (key->hw_key_idx < 32) {
		mask = 1 << key->hw_key_idx;

		rt73usb_register_read(rt2x00dev, SEC_CSR2, &reg);
		if (crypto->cmd == SET_KEY)
			reg |= mask;
		else if (crypto->cmd == DISABLE_KEY)
			reg &= ~mask;
		rt73usb_register_write(rt2x00dev, SEC_CSR2, reg);
	} else {
		mask = 1 << (key->hw_key_idx - 32);

		rt73usb_register_read(rt2x00dev, SEC_CSR3, &reg);
		if (crypto->cmd == SET_KEY)
			reg |= mask;
		else if (crypto->cmd == DISABLE_KEY)
			reg &= ~mask;
		rt73usb_register_write(rt2x00dev, SEC_CSR3, reg);
	}

	return 0;
}

static void rt73usb_config_filter(struct rt2x00_dev *rt2x00dev,
				  const unsigned int filter_flags)
{
	u32 reg;

	/*
	 * Start configuration steps.
	 * Note that the version error will always be dropped
	 * and broadcast frames will always be accepted since
	 * there is no filter for it at this time.
	 */
	rt73usb_register_read(rt2x00dev, TXRX_CSR0, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_CRC,
			   !(filter_flags & FIF_FCSFAIL));
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_PHYSICAL,
			   !(filter_flags & FIF_PLCPFAIL));
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_CONTROL,
			   !(filter_flags & FIF_CONTROL));
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_NOT_TO_ME,
			   !(filter_flags & FIF_PROMISC_IN_BSS));
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_TO_DS,
			   !(filter_flags & FIF_PROMISC_IN_BSS) &&
			   !rt2x00dev->intf_ap_count);
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_VERSION_ERROR, 1);
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_MULTICAST,
			   !(filter_flags & FIF_ALLMULTI));
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_BROADCAST, 0);
	rt2x00_set_field32(&reg, TXRX_CSR0_DROP_ACK_CTS,
			   !(filter_flags & FIF_CONTROL));
	rt73usb_register_write(rt2x00dev, TXRX_CSR0, reg);
}

static void rt73usb_config_intf(struct rt2x00_dev *rt2x00dev,
				struct rt2x00_intf *intf,
				struct rt2x00intf_conf *conf,
				const unsigned int flags)
{
	unsigned int beacon_base;
	u32 reg;

	if (flags & CONFIG_UPDATE_TYPE) {
		/*
		 * Clear current synchronisation setup.
		 * For the Beacon base registers we only need to clear
		 * the first byte since that byte contains the VALID and OWNER
		 * bits which (when set to 0) will invalidate the entire beacon.
		 */
		beacon_base = HW_BEACON_OFFSET(intf->beacon->entry_idx);
		rt73usb_register_write(rt2x00dev, beacon_base, 0);

		/*
		 * Enable synchronisation.
		 */
		rt73usb_register_read(rt2x00dev, TXRX_CSR9, &reg);
		rt2x00_set_field32(&reg, TXRX_CSR9_TSF_TICKING, 1);
		rt2x00_set_field32(&reg, TXRX_CSR9_TSF_SYNC, conf->sync);
		rt2x00_set_field32(&reg, TXRX_CSR9_TBTT_ENABLE, 1);
		rt73usb_register_write(rt2x00dev, TXRX_CSR9, reg);
	}

	if (flags & CONFIG_UPDATE_MAC) {
		reg = le32_to_cpu(conf->mac[1]);
		rt2x00_set_field32(&reg, MAC_CSR3_UNICAST_TO_ME_MASK, 0xff);
		conf->mac[1] = cpu_to_le32(reg);

		rt73usb_register_multiwrite(rt2x00dev, MAC_CSR2,
					    conf->mac, sizeof(conf->mac));
	}

	if (flags & CONFIG_UPDATE_BSSID) {
		reg = le32_to_cpu(conf->bssid[1]);
		rt2x00_set_field32(&reg, MAC_CSR5_BSS_ID_MASK, 3);
		conf->bssid[1] = cpu_to_le32(reg);

		rt73usb_register_multiwrite(rt2x00dev, MAC_CSR4,
					    conf->bssid, sizeof(conf->bssid));
	}
}

static void rt73usb_config_erp(struct rt2x00_dev *rt2x00dev,
			       struct rt2x00lib_erp *erp)
{
	u32 reg;

	rt73usb_register_read(rt2x00dev, TXRX_CSR0, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR0_RX_ACK_TIMEOUT, erp->ack_timeout);
	rt73usb_register_write(rt2x00dev, TXRX_CSR0, reg);

	rt73usb_register_read(rt2x00dev, TXRX_CSR4, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR4_AUTORESPOND_PREAMBLE,
			   !!erp->short_preamble);
	rt73usb_register_write(rt2x00dev, TXRX_CSR4, reg);

	rt73usb_register_write(rt2x00dev, TXRX_CSR5, erp->basic_rates);

	rt73usb_register_read(rt2x00dev, MAC_CSR9, &reg);
	rt2x00_set_field32(&reg, MAC_CSR9_SLOT_TIME, erp->slot_time);
	rt73usb_register_write(rt2x00dev, MAC_CSR9, reg);

	rt73usb_register_read(rt2x00dev, MAC_CSR8, &reg);
	rt2x00_set_field32(&reg, MAC_CSR8_SIFS, erp->sifs);
	rt2x00_set_field32(&reg, MAC_CSR8_SIFS_AFTER_RX_OFDM, 3);
	rt2x00_set_field32(&reg, MAC_CSR8_EIFS, erp->eifs);
	rt73usb_register_write(rt2x00dev, MAC_CSR8, reg);
}

static void rt73usb_config_antenna_5x(struct rt2x00_dev *rt2x00dev,
				      struct antenna_setup *ant)
{
	u8 r3;
	u8 r4;
	u8 r77;
	u8 temp;

	rt73usb_bbp_read(rt2x00dev, 3, &r3);
	rt73usb_bbp_read(rt2x00dev, 4, &r4);
	rt73usb_bbp_read(rt2x00dev, 77, &r77);

	rt2x00_set_field8(&r3, BBP_R3_SMART_MODE, 0);

	/*
	 * Configure the RX antenna.
	 */
	switch (ant->rx) {
	case ANTENNA_HW_DIVERSITY:
		rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA_CONTROL, 2);
		temp = !test_bit(CONFIG_FRAME_TYPE, &rt2x00dev->flags)
		       && (rt2x00dev->curr_band != IEEE80211_BAND_5GHZ);
		rt2x00_set_field8(&r4, BBP_R4_RX_FRAME_END, temp);
		break;
	case ANTENNA_A:
		rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA_CONTROL, 1);
		rt2x00_set_field8(&r4, BBP_R4_RX_FRAME_END, 0);
		if (rt2x00dev->curr_band == IEEE80211_BAND_5GHZ)
			rt2x00_set_field8(&r77, BBP_R77_RX_ANTENNA, 0);
		else
			rt2x00_set_field8(&r77, BBP_R77_RX_ANTENNA, 3);
		break;
	case ANTENNA_B:
	default:
		rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA_CONTROL, 1);
		rt2x00_set_field8(&r4, BBP_R4_RX_FRAME_END, 0);
		if (rt2x00dev->curr_band == IEEE80211_BAND_5GHZ)
			rt2x00_set_field8(&r77, BBP_R77_RX_ANTENNA, 3);
		else
			rt2x00_set_field8(&r77, BBP_R77_RX_ANTENNA, 0);
		break;
	}

	rt73usb_bbp_write(rt2x00dev, 77, r77);
	rt73usb_bbp_write(rt2x00dev, 3, r3);
	rt73usb_bbp_write(rt2x00dev, 4, r4);
}

static void rt73usb_config_antenna_2x(struct rt2x00_dev *rt2x00dev,
				      struct antenna_setup *ant)
{
	u8 r3;
	u8 r4;
	u8 r77;

	rt73usb_bbp_read(rt2x00dev, 3, &r3);
	rt73usb_bbp_read(rt2x00dev, 4, &r4);
	rt73usb_bbp_read(rt2x00dev, 77, &r77);

	rt2x00_set_field8(&r3, BBP_R3_SMART_MODE, 0);
	rt2x00_set_field8(&r4, BBP_R4_RX_FRAME_END,
			  !test_bit(CONFIG_FRAME_TYPE, &rt2x00dev->flags));

	/*
	 * Configure the RX antenna.
	 */
	switch (ant->rx) {
	case ANTENNA_HW_DIVERSITY:
		rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA_CONTROL, 2);
		break;
	case ANTENNA_A:
		rt2x00_set_field8(&r77, BBP_R77_RX_ANTENNA, 3);
		rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA_CONTROL, 1);
		break;
	case ANTENNA_B:
	default:
		rt2x00_set_field8(&r77, BBP_R77_RX_ANTENNA, 0);
		rt2x00_set_field8(&r4, BBP_R4_RX_ANTENNA_CONTROL, 1);
		break;
	}

	rt73usb_bbp_write(rt2x00dev, 77, r77);
	rt73usb_bbp_write(rt2x00dev, 3, r3);
	rt73usb_bbp_write(rt2x00dev, 4, r4);
}

struct antenna_sel {
	u8 word;
	/*
	 * value[0] -> non-LNA
	 * value[1] -> LNA
	 */
	u8 value[2];
};

static const struct antenna_sel antenna_sel_a[] = {
	{ 96,  { 0x58, 0x78 } },
	{ 104, { 0x38, 0x48 } },
	{ 75,  { 0xfe, 0x80 } },
	{ 86,  { 0xfe, 0x80 } },
	{ 88,  { 0xfe, 0x80 } },
	{ 35,  { 0x60, 0x60 } },
	{ 97,  { 0x58, 0x58 } },
	{ 98,  { 0x58, 0x58 } },
};

static const struct antenna_sel antenna_sel_bg[] = {
	{ 96,  { 0x48, 0x68 } },
	{ 104, { 0x2c, 0x3c } },
	{ 75,  { 0xfe, 0x80 } },
	{ 86,  { 0xfe, 0x80 } },
	{ 88,  { 0xfe, 0x80 } },
	{ 35,  { 0x50, 0x50 } },
	{ 97,  { 0x48, 0x48 } },
	{ 98,  { 0x48, 0x48 } },
};

static void rt73usb_config_ant(struct rt2x00_dev *rt2x00dev,
			       struct antenna_setup *ant)
{
	const struct antenna_sel *sel;
	unsigned int lna;
	unsigned int i;
	u32 reg;

	/*
	 * We should never come here because rt2x00lib is supposed
	 * to catch this and send us the correct antenna explicitely.
	 */
	BUG_ON(ant->rx == ANTENNA_SW_DIVERSITY ||
	       ant->tx == ANTENNA_SW_DIVERSITY);

	if (rt2x00dev->curr_band == IEEE80211_BAND_5GHZ) {
		sel = antenna_sel_a;
		lna = test_bit(CONFIG_EXTERNAL_LNA_A, &rt2x00dev->flags);
	} else {
		sel = antenna_sel_bg;
		lna = test_bit(CONFIG_EXTERNAL_LNA_BG, &rt2x00dev->flags);
	}

	for (i = 0; i < ARRAY_SIZE(antenna_sel_a); i++)
		rt73usb_bbp_write(rt2x00dev, sel[i].word, sel[i].value[lna]);

	rt73usb_register_read(rt2x00dev, PHY_CSR0, &reg);

	rt2x00_set_field32(&reg, PHY_CSR0_PA_PE_BG,
			   (rt2x00dev->curr_band == IEEE80211_BAND_2GHZ));
	rt2x00_set_field32(&reg, PHY_CSR0_PA_PE_A,
			   (rt2x00dev->curr_band == IEEE80211_BAND_5GHZ));

	rt73usb_register_write(rt2x00dev, PHY_CSR0, reg);

	if (rt2x00_rf(&rt2x00dev->chip, RF5226) ||
	    rt2x00_rf(&rt2x00dev->chip, RF5225))
		rt73usb_config_antenna_5x(rt2x00dev, ant);
	else if (rt2x00_rf(&rt2x00dev->chip, RF2528) ||
		 rt2x00_rf(&rt2x00dev->chip, RF2527))
		rt73usb_config_antenna_2x(rt2x00dev, ant);
}

static void rt73usb_config_lna_gain(struct rt2x00_dev *rt2x00dev,
				    struct rt2x00lib_conf *libconf)
{
	u16 eeprom;
	short lna_gain = 0;

	if (libconf->conf->channel->band == IEEE80211_BAND_2GHZ) {
		if (test_bit(CONFIG_EXTERNAL_LNA_BG, &rt2x00dev->flags))
			lna_gain += 14;

		rt2x00_eeprom_read(rt2x00dev, EEPROM_RSSI_OFFSET_BG, &eeprom);
		lna_gain -= rt2x00_get_field16(eeprom, EEPROM_RSSI_OFFSET_BG_1);
	} else {
		rt2x00_eeprom_read(rt2x00dev, EEPROM_RSSI_OFFSET_A, &eeprom);
		lna_gain -= rt2x00_get_field16(eeprom, EEPROM_RSSI_OFFSET_A_1);
	}

	rt2x00dev->lna_gain = lna_gain;
}

static void rt73usb_config_channel(struct rt2x00_dev *rt2x00dev,
				   struct rf_channel *rf, const int txpower)
{
	u8 r3;
	u8 r94;
	u8 smart;

	rt2x00_set_field32(&rf->rf3, RF3_TXPOWER, TXPOWER_TO_DEV(txpower));
	rt2x00_set_field32(&rf->rf4, RF4_FREQ_OFFSET, rt2x00dev->freq_offset);

	smart = !(rt2x00_rf(&rt2x00dev->chip, RF5225) ||
		  rt2x00_rf(&rt2x00dev->chip, RF2527));

	rt73usb_bbp_read(rt2x00dev, 3, &r3);
	rt2x00_set_field8(&r3, BBP_R3_SMART_MODE, smart);
	rt73usb_bbp_write(rt2x00dev, 3, r3);

	r94 = 6;
	if (txpower > MAX_TXPOWER && txpower <= (MAX_TXPOWER + r94))
		r94 += txpower - MAX_TXPOWER;
	else if (txpower < MIN_TXPOWER && txpower >= (MIN_TXPOWER - r94))
		r94 += txpower;
	rt73usb_bbp_write(rt2x00dev, 94, r94);

	rt73usb_rf_write(rt2x00dev, 1, rf->rf1);
	rt73usb_rf_write(rt2x00dev, 2, rf->rf2);
	rt73usb_rf_write(rt2x00dev, 3, rf->rf3 & ~0x00000004);
	rt73usb_rf_write(rt2x00dev, 4, rf->rf4);

	rt73usb_rf_write(rt2x00dev, 1, rf->rf1);
	rt73usb_rf_write(rt2x00dev, 2, rf->rf2);
	rt73usb_rf_write(rt2x00dev, 3, rf->rf3 | 0x00000004);
	rt73usb_rf_write(rt2x00dev, 4, rf->rf4);

	rt73usb_rf_write(rt2x00dev, 1, rf->rf1);
	rt73usb_rf_write(rt2x00dev, 2, rf->rf2);
	rt73usb_rf_write(rt2x00dev, 3, rf->rf3 & ~0x00000004);
	rt73usb_rf_write(rt2x00dev, 4, rf->rf4);

	udelay(10);
}

static void rt73usb_config_txpower(struct rt2x00_dev *rt2x00dev,
				   const int txpower)
{
	struct rf_channel rf;

	rt2x00_rf_read(rt2x00dev, 1, &rf.rf1);
	rt2x00_rf_read(rt2x00dev, 2, &rf.rf2);
	rt2x00_rf_read(rt2x00dev, 3, &rf.rf3);
	rt2x00_rf_read(rt2x00dev, 4, &rf.rf4);

	rt73usb_config_channel(rt2x00dev, &rf, txpower);
}

static void rt73usb_config_retry_limit(struct rt2x00_dev *rt2x00dev,
				       struct rt2x00lib_conf *libconf)
{
	u32 reg;

	rt73usb_register_read(rt2x00dev, TXRX_CSR4, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR4_LONG_RETRY_LIMIT,
			   libconf->conf->long_frame_max_tx_count);
	rt2x00_set_field32(&reg, TXRX_CSR4_SHORT_RETRY_LIMIT,
			   libconf->conf->short_frame_max_tx_count);
	rt73usb_register_write(rt2x00dev, TXRX_CSR4, reg);
}

static void rt73usb_config_duration(struct rt2x00_dev *rt2x00dev,
				    struct rt2x00lib_conf *libconf)
{
	u32 reg;

	rt73usb_register_read(rt2x00dev, TXRX_CSR0, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR0_TSF_OFFSET, IEEE80211_HEADER);
	rt73usb_register_write(rt2x00dev, TXRX_CSR0, reg);

	rt73usb_register_read(rt2x00dev, TXRX_CSR4, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR4_AUTORESPOND_ENABLE, 1);
	rt73usb_register_write(rt2x00dev, TXRX_CSR4, reg);

	rt73usb_register_read(rt2x00dev, TXRX_CSR9, &reg);
	rt2x00_set_field32(&reg, TXRX_CSR9_BEACON_INTERVAL,
			   libconf->conf->beacon_int * 16);
	rt73usb_register_write(rt2x00dev, TXRX_CSR9, reg);
}

static void rt73usb_config(struct rt2x00_dev *rt2x00dev,
			   struct rt2x00lib_conf *libconf,
			   const unsigned int flags)
{
	/* Always recalculate LNA gain before changing configuration */
	rt73usb_config_lna_gain(rt2x00dev, libconf);

	if (flags & IEEE80211_CONF_CHANGE_CHANNEL)
		rt73usb_config_channel(rt2x00dev, &libconf->rf,
				       libconf->conf->power_level);
	if ((flags & IEEE80211_CONF_CHANGE_POWER) &&
	    !(flags & IEEE80211_CONF_CHANGE_CHANNEL))
		rt73usb_config_txpower(rt2x00dev, libconf->conf->power_level);
	if (flags & IEEE80211_CONF_CHANGE_RETRY_LIMITS)
		rt73usb_config_retry_limit(rt2x00dev, libconf);
	if (flags & IEEE80211_CONF_CHANGE_BEACON_INTERVAL)
		rt73usb_config_duration(rt2x00dev, libconf);
}

/*
 * Link tuning
 */
static void rt73usb_link_stats(struct rt2x00_dev *rt2x00dev,
			       struct link_qual *qual)
{
	u32 reg;

	/*
	 * Update FCS error count from register.
	 */
	rt73usb_register_read(rt2x00dev, STA_CSR0, &reg);
	qual->rx_failed = rt2x00_get_field32(reg, STA_CSR0_FCS_ERROR);

	/*
	 * Update False CCA count from register.
	 */
	rt73usb_register_read(rt2x00dev, STA_CSR1, &reg);
	qual->false_cca = rt2x00_get_field32(reg, STA_CSR1_FALSE_CCA_ERROR);
}

static void rt73usb_reset_tuner(struct rt2x00_dev *rt2x00dev)
{
	rt73usb_bbp_write(rt2x00dev, 17, 0x20);
	rt2x00dev->link.vgc_level = 0x20;
}

static void rt73usb_link_tuner(struct rt2x00_dev *rt2x00dev)
{
	int rssi = rt2x00_get_link_rssi(&rt2x00dev->link);
	u8 r17;
	u8 up_bound;
	u8 low_bound;

	rt73usb_bbp_read(rt2x00dev, 17, &r17);

	/*
	 * Determine r17 bounds.
	 */
	if (rt2x00dev->rx_status.band == IEEE80211_BAND_5GHZ) {
		low_bound = 0x28;
		up_bound = 0x48;

		if (test_bit(CONFIG_EXTERNAL_LNA_A, &rt2x00dev->flags)) {
			low_bound += 0x10;
			up_bound += 0x10;
		}
	} else {
		if (rssi > -82) {
			low_bound = 0x1c;
			up_bound = 0x40;
		} else if (rssi > -84) {
			low_bound = 0x1c;
			up_bound = 0x20;
		} else {
			low_bound = 0x1c;