rt2800lib.c

/*
	Copyright (C) 2010 Willow Garage <http://www.willowgarage.com>
	Copyright (C) 2010 Ivo van Doorn <IvDoorn@gmail.com>
	Copyright (C) 2009 Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
	Copyright (C) 2009 Gertjan van Wingerde <gwingerde@gmail.com>

	Based on the original rt2800pci.c and rt2800usb.c.
	  Copyright (C) 2009 Alban Browaeys <prahal@yahoo.com>
	  Copyright (C) 2009 Felix Fietkau <nbd@openwrt.org>
	  Copyright (C) 2009 Luis Correia <luis.f.correia@gmail.com>
	  Copyright (C) 2009 Mattias Nissler <mattias.nissler@gmx.de>
	  Copyright (C) 2009 Mark Asselstine <asselsm@gmail.com>
	  Copyright (C) 2009 Xose Vazquez Perez <xose.vazquez@gmail.com>
	  <http://rt2x00.serialmonkey.com>

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the
	Free Software Foundation, Inc.,
	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
	Module: rt2800lib
	Abstract: rt2800 generic device routines.
 */

#include <linux/crc-ccitt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>

#include "rt2x00.h"
#include "rt2800lib.h"
#include "rt2800.h"

/*
 * Register access.
 * All access to the CSR registers will go through the methods
 * rt2800_register_read and rt2800_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) \
	rt2800_regbusy_read((__dev), BBP_CSR_CFG, BBP_CSR_CFG_BUSY, (__reg))
#define WAIT_FOR_RFCSR(__dev, __reg) \
	rt2800_regbusy_read((__dev), RF_CSR_CFG, RF_CSR_CFG_BUSY, (__reg))
#define WAIT_FOR_RF(__dev, __reg) \
	rt2800_regbusy_read((__dev), RF_CSR_CFG0, RF_CSR_CFG0_BUSY, (__reg))
#define WAIT_FOR_MCU(__dev, __reg) \
	rt2800_regbusy_read((__dev), H2M_MAILBOX_CSR, \
			    H2M_MAILBOX_CSR_OWNER, (__reg))

static inline bool rt2800_is_305x_soc(struct rt2x00_dev *rt2x00dev)
{
	/* check for rt2872 on SoC */
	if (!rt2x00_is_soc(rt2x00dev) ||
	    !rt2x00_rt(rt2x00dev, RT2872))
		return false;

	/* we know for sure that these rf chipsets are used on rt305x boards */
	if (rt2x00_rf(rt2x00dev, RF3020) ||
	    rt2x00_rf(rt2x00dev, RF3021) ||
	    rt2x00_rf(rt2x00dev, RF3022))
		return true;

	NOTICE(rt2x00dev, "Unknown RF chipset on rt305x\n");
	return false;
}

static void rt2800_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, BBP_CSR_CFG_VALUE, value);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_REGNUM, word);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_BUSY, 1);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_READ_CONTROL, 0);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_BBP_RW_MODE, 1);

		rt2800_register_write_lock(rt2x00dev, BBP_CSR_CFG, reg);
	}

	mutex_unlock(&rt2x00dev->csr_mutex);
}

static void rt2800_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, BBP_CSR_CFG_REGNUM, word);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_BUSY, 1);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_READ_CONTROL, 1);
		rt2x00_set_field32(&reg, BBP_CSR_CFG_BBP_RW_MODE, 1);

		rt2800_register_write_lock(rt2x00dev, BBP_CSR_CFG, reg);

		WAIT_FOR_BBP(rt2x00dev, &reg);
	}

	*value = rt2x00_get_field32(reg, BBP_CSR_CFG_VALUE);

	mutex_unlock(&rt2x00dev->csr_mutex);
}

static void rt2800_rfcsr_write(struct rt2x00_dev *rt2x00dev,
			       const unsigned int word, const u8 value)
{
	u32 reg;

	mutex_lock(&rt2x00dev->csr_mutex);

	/*
	 * Wait until the RFCSR becomes available, afterwards we
	 * can safely write the new data into the register.
	 */
	if (WAIT_FOR_RFCSR(rt2x00dev, &reg)) {
		reg = 0;
		rt2x00_set_field32(&reg, RF_CSR_CFG_DATA, value);
		rt2x00_set_field32(&reg, RF_CSR_CFG_REGNUM, word);
		rt2x00_set_field32(&reg, RF_CSR_CFG_WRITE, 1);
		rt2x00_set_field32(&reg, RF_CSR_CFG_BUSY, 1);

		rt2800_register_write_lock(rt2x00dev, RF_CSR_CFG, reg);
	}

	mutex_unlock(&rt2x00dev->csr_mutex);
}

static void rt2800_rfcsr_read(struct rt2x00_dev *rt2x00dev,
			      const unsigned int word, u8 *value)
{
	u32 reg;

	mutex_lock(&rt2x00dev->csr_mutex);

	/*
	 * Wait until the RFCSR 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_RFCSR(rt2x00dev, &reg)) {
		reg = 0;
		rt2x00_set_field32(&reg, RF_CSR_CFG_REGNUM, word);
		rt2x00_set_field32(&reg, RF_CSR_CFG_WRITE, 0);
		rt2x00_set_field32(&reg, RF_CSR_CFG_BUSY, 1);

		rt2800_register_write_lock(rt2x00dev, RF_CSR_CFG, reg);

		WAIT_FOR_RFCSR(rt2x00dev, &reg);
	}

	*value = rt2x00_get_field32(reg, RF_CSR_CFG_DATA);

	mutex_unlock(&rt2x00dev->csr_mutex);
}

static void rt2800_rf_write(struct rt2x00_dev *rt2x00dev,
			    const unsigned int word, const u32 value)