rt73usb.c

/*
	Copyright (C) 2004 - 2009 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
 * rt2x00usb_register_read and rt2x00usb_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
 */
#define WAIT_FOR_BBP(__dev, __reg) \
	rt2x00usb_regbusy_read((__dev), PHY_CSR3, PHY_CSR3_BUSY, (__reg))
#define WAIT_FOR_RF(__dev, __reg) \
	rt2x00usb_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);

		rt2x00usb_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);

		rt2x00usb_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;

	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);

		rt2x00usb_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		= rt2x00usb_register_read,
		.write		= rt2x00usb_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 */

static int rt73usb_rfkill_poll(struct rt2x00_dev *rt2x00dev)
{
	u32 reg;

	rt2x00usb_register_read(rt2x00dev, MAC_CSR13, &reg);
	return rt2x00_get_field32(reg, MAC_CSR13_BIT7);
}

#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;