drivers/net/wireless/wl12xx/wl1271_spi.c - linux - Git at Google

 /*
  * This file is part of wl1271
  *
  * Copyright (C) 2008-2009 Nokia Corporation
  *
  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * version 2 as published by the Free Software Foundation.
  *
  * 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., 51 Franklin St, Fifth Floor, Boston, MA
  * 02110-1301 USA
  *
  */

 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/crc7.h>
 #include <linux/spi/spi.h>

 #include "wl1271.h"
 #include "wl12xx_80211.h"
 #include "wl1271_spi.h"

 static int wl1271_translate_addr(struct wl1271 *wl, int addr)
 {
 	/*
 	 * To translate, first check to which window of addresses the
 	 * particular address belongs. Then subtract the starting address
 	 * of that window from the address. Then, add offset of the
 	 * translated region.
 	 *
 	 * The translated regions occur next to each other in physical device
 	 * memory, so just add the sizes of the preceeding address regions to
 	 * get the offset to the new region.
 	 *
 	 * Currently, only the two first regions are addressed, and the
 	 * assumption is that all addresses will fall into either of those
 	 * two.
 	 */
 	if ((addr >= wl->part.reg.start) &&
 	    (addr < wl->part.reg.start + wl->part.reg.size))
 		return addr - wl->part.reg.start + wl->part.mem.size;
 	else
 		return addr - wl->part.mem.start;
 }

 void wl1271_spi_reset(struct wl1271 *wl)
 {
 	u8 *cmd;
 	struct spi_transfer t;
 	struct spi_message m;

 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 	if (!cmd) {
 		wl1271_error("could not allocate cmd for spi reset");
 		return;
 	}

 	memset(&t, 0, sizeof(t));
 	spi_message_init(&m);

 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);

 	t.tx_buf = cmd;
 	t.len = WSPI_INIT_CMD_LEN;
 	spi_message_add_tail(&t, &m);

 	spi_sync(wl->spi, &m);

 	wl1271_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
 }

 void wl1271_spi_init(struct wl1271 *wl)
 {
 	u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
 	struct spi_transfer t;
 	struct spi_message m;

 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
 	if (!cmd) {
 		wl1271_error("could not allocate cmd for spi init");
 		return;
 	}

 	memset(crc, 0, sizeof(crc));
 	memset(&t, 0, sizeof(t));
 	spi_message_init(&m);

 	/*
 	 * Set WSPI_INIT_COMMAND
 	 * the data is being send from the MSB to LSB
 	 */
 	cmd[2] = 0xff;
 	cmd[3] = 0xff;
 	cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
 	cmd[0] = 0;
 	cmd[7] = 0;
 	cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
 	cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;

 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
 		cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
 	else
 		cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;

 	cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;

 	crc[0] = cmd[1];
 	crc[1] = cmd[0];
 	crc[2] = cmd[7];
 	crc[3] = cmd[6];
 	crc[4] = cmd[5];

 	cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
 	cmd[4] |= WSPI_INIT_CMD_END;

 	t.tx_buf = cmd;
 	t.len = WSPI_INIT_CMD_LEN;
 	spi_message_add_tail(&t, &m);

 	spi_sync(wl->spi, &m);

 	wl1271_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
 }

 /* Set the SPI partitions to access the chip addresses
  *
  * To simplify driver code, a fixed (virtual) memory map is defined for
  * register and memory addresses. Because in the chipset, in different stages
  * of operation, those addresses will move around, an address translation
  * mechanism is required.
  *
  * There are four partitions (three memory and one register partition),
  * which are mapped to two different areas of the hardware memory.
  *
  *                                Virtual address
  *                                     space
  *
  *                                    |    |
  *                                 ...+----+--> mem.start
  *          Physical address    ...   |    |
  *               space       ...      |    | [PART_0]
  *                        ...         |    |
  *  00000000  <--+----+...         ...+----+--> mem.start + mem.size
  *               |    |         ...   |    |
  *               |MEM |      ...      |    |
  *               |    |   ...         |    |
  *  mem.size  <--+----+...            |    | {unused area)
  *               |    |   ...         |    |
  *               |REG |      ...      |    |
  *  mem.size     |    |         ...   |    |
  *      +     <--+----+...         ...+----+--> reg.start
  *  reg.size     |    |   ...         |    |
  *               |MEM2|      ...      |    | [PART_1]
  *               |    |         ...   |    |
  *                                 ...+----+--> reg.start + reg.size
  *                                    |    |
  *
  */
 int wl1271_set_partition(struct wl1271 *wl,
 			 struct wl1271_partition_set *p)
 {
 	/* copy partition info */
 	memcpy(&wl->part, p, sizeof(*p));

 	wl1271_debug(DEBUG_SPI, "mem_start %08X mem_size %08X",
 		     p->mem.start, p->mem.size);
 	wl1271_debug(DEBUG_SPI, "reg_start %08X reg_size %08X",
 		     p->reg.start, p->reg.size);
 	wl1271_debug(DEBUG_SPI, "mem2_start %08X mem2_size %08X",
 		     p->mem2.start, p->mem2.size);
 	wl1271_debug(DEBUG_SPI, "mem3_start %08X mem3_size %08X",
 		     p->mem3.start, p->mem3.size);

 	/* write partition info to the chipset */
 	wl1271_raw_write32(wl, HW_PART0_START_ADDR, p->mem.start);
 	wl1271_raw_write32(wl, HW_PART0_SIZE_ADDR, p->mem.size);
 	wl1271_raw_write32(wl, HW_PART1_START_ADDR, p->reg.start);
 	wl1271_raw_write32(wl, HW_PART1_SIZE_ADDR, p->reg.size);
 	wl1271_raw_write32(wl, HW_PART2_START_ADDR, p->mem2.start);
 	wl1271_raw_write32(wl, HW_PART2_SIZE_ADDR, p->mem2.size);
 	wl1271_raw_write32(wl, HW_PART3_START_ADDR, p->mem3.start);

 	return 0;
 }

 #define WL1271_BUSY_WORD_TIMEOUT 1000

 /* FIXME: Check busy words, removed due to SPI bug */
 #if 0
 static void wl1271_spi_read_busy(struct wl1271 *wl, void *buf, size_t len)
 {
 	struct spi_transfer t[1];
 	struct spi_message m;
 	u32 *busy_buf;
 	int num_busy_bytes = 0;

 	wl1271_info("spi read BUSY!");

 	/*
 	 * Look for the non-busy word in the read buffer, and if found,
 	 * read in the remaining data into the buffer.
 	 */
 	busy_buf = (u32 *)buf;
 	for (; (u32)busy_buf < (u32)buf + len; busy_buf++) {
 		num_busy_bytes += sizeof(u32);
 		if (*busy_buf & 0x1) {
 			spi_message_init(&m);
 			memset(t, 0, sizeof(t));
 			memmove(buf, busy_buf, len - num_busy_bytes);
 			t[0].rx_buf = buf + (len - num_busy_bytes);
 			t[0].len = num_busy_bytes;
 			spi_message_add_tail(&t[0], &m);
 			spi_sync(wl->spi, &m);
 			return;
 		}
 	}

 	/*
 	 * Read further busy words from SPI until a non-busy word is
 	 * encountered, then read the data itself into the buffer.
 	 */
 	wl1271_info("spi read BUSY-polling needed!");

 	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
 	busy_buf = wl->buffer_busyword;
 	while (num_busy_bytes) {
 		num_busy_bytes--;
 		spi_message_init(&m);
 		memset(t, 0, sizeof(t));
 		t[0].rx_buf = busy_buf;
 		t[0].len = sizeof(u32);
 		spi_message_add_tail(&t[0], &m);
 		spi_sync(wl->spi, &m);

 		if (*busy_buf & 0x1) {
 			spi_message_init(&m);
 			memset(t, 0, sizeof(t));
 			t[0].rx_buf = buf;
 			t[0].len = len;
 			spi_message_add_tail(&t[0], &m);
 			spi_sync(wl->spi, &m);
 			return;
 		}
 	}

 	/* The SPI bus is unresponsive, the read failed. */
 	memset(buf, 0, len);
 	wl1271_error("SPI read busy-word timeout!\n");
 }
 #endif

 void wl1271_spi_raw_read(struct wl1271 *wl, int addr, void *buf,
 			 size_t len, bool fixed)
 {
 	struct spi_transfer t[3];
 	struct spi_message m;
 	u32 *busy_buf;
 	u32 *cmd;

 	cmd = &wl->buffer_cmd;
 	busy_buf = wl->buffer_busyword;

 	*cmd = 0;
 	*cmd |= WSPI_CMD_READ;
 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;

 	if (fixed)
 		*cmd |= WSPI_CMD_FIXED;

 	spi_message_init(&m);
 	memset(t, 0, sizeof(t));

 	t[0].tx_buf = cmd;
 	t[0].len = 4;
 	spi_message_add_tail(&t[0], &m);

 	/* Busy and non busy words read */
 	t[1].rx_buf = busy_buf;
 	t[1].len = WL1271_BUSY_WORD_LEN;
 	spi_message_add_tail(&t[1], &m);

 	t[2].rx_buf = buf;
 	t[2].len = len;
 	spi_message_add_tail(&t[2], &m);

 	spi_sync(wl->spi, &m);

 	/* FIXME: Check busy words, removed due to SPI bug */
 	/* if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1))
 	   wl1271_spi_read_busy(wl, buf, len); */

 	wl1271_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
 	wl1271_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
 }

 void wl1271_spi_raw_write(struct wl1271 *wl, int addr, void *buf,
 			  size_t len, bool fixed)
 {
 	struct spi_transfer t[2];
 	struct spi_message m;
 	u32 *cmd;

 	cmd = &wl->buffer_cmd;

 	*cmd = 0;
 	*cmd |= WSPI_CMD_WRITE;
 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;

 	if (fixed)
 		*cmd |= WSPI_CMD_FIXED;

 	spi_message_init(&m);
 	memset(t, 0, sizeof(t));

 	t[0].tx_buf = cmd;
 	t[0].len = sizeof(*cmd);
 	spi_message_add_tail(&t[0], &m);

 	t[1].tx_buf = buf;
 	t[1].len = len;
 	spi_message_add_tail(&t[1], &m);

 	spi_sync(wl->spi, &m);

 	wl1271_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
 	wl1271_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
 }

 void wl1271_spi_read(struct wl1271 *wl, int addr, void *buf, size_t len,
 		     bool fixed)
 {
 	int physical;

 	physical = wl1271_translate_addr(wl, addr);

 	wl1271_spi_raw_read(wl, physical, buf, len, fixed);
 }

 void wl1271_spi_write(struct wl1271 *wl, int addr, void *buf, size_t len,
 		      bool fixed)
 {
 	int physical;

 	physical = wl1271_translate_addr(wl, addr);

 	wl1271_spi_raw_write(wl, physical, buf, len, fixed);
 }

 u32 wl1271_spi_read32(struct wl1271 *wl, int addr)
 {
 	return wl1271_raw_read32(wl, wl1271_translate_addr(wl, addr));
 }

 void wl1271_spi_write32(struct wl1271 *wl, int addr, u32 val)
 {
 	wl1271_raw_write32(wl, wl1271_translate_addr(wl, addr), val);
 }

 void wl1271_top_reg_write(struct wl1271 *wl, int addr, u16 val)
 {
 	/* write address >> 1 + 0x30000 to OCP_POR_CTR */
 	addr = (addr >> 1) + 0x30000;
 	wl1271_spi_write32(wl, OCP_POR_CTR, addr);

 	/* write value to OCP_POR_WDATA */
 	wl1271_spi_write32(wl, OCP_DATA_WRITE, val);

 	/* write 1 to OCP_CMD */
 	wl1271_spi_write32(wl, OCP_CMD, OCP_CMD_WRITE);
 }

 u16 wl1271_top_reg_read(struct wl1271 *wl, int addr)
 {
 	u32 val;
 	int timeout = OCP_CMD_LOOP;

 	/* write address >> 1 + 0x30000 to OCP_POR_CTR */
 	addr = (addr >> 1) + 0x30000;
 	wl1271_spi_write32(wl, OCP_POR_CTR, addr);

 	/* write 2 to OCP_CMD */
 	wl1271_spi_write32(wl, OCP_CMD, OCP_CMD_READ);

 	/* poll for data ready */
 	do {
 		val = wl1271_spi_read32(wl, OCP_DATA_READ);
 		timeout--;
 	} while (!(val & OCP_READY_MASK) && timeout);

 	if (!timeout) {
 		wl1271_warning("Top register access timed out.");
 		return 0xffff;
 	}

 	/* check data status and return if OK */
 	if ((val & OCP_STATUS_MASK) == OCP_STATUS_OK)
 		return val & 0xffff;
 	else {
 		wl1271_warning("Top register access returned error.");
 		return 0xffff;
 	}
 }
	/*
	* This file is part of wl1271
	*
	* Copyright (C) 2008-2009 Nokia Corporation
	*
	* Contact: Luciano Coelho <luciano.coelho@nokia.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* version 2 as published by the Free Software Foundation.
	*
	* 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., 51 Franklin St, Fifth Floor, Boston, MA
	* 02110-1301 USA
	*
	*/

	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/crc7.h>
	#include <linux/spi/spi.h>

	#include "wl1271.h"
	#include "wl12xx_80211.h"
	#include "wl1271_spi.h"

	static int wl1271_translate_addr(struct wl1271 *wl, int addr)
	{
	/*
	* To translate, first check to which window of addresses the
	* particular address belongs. Then subtract the starting address
	* of that window from the address. Then, add offset of the
	* translated region.
	*
	* The translated regions occur next to each other in physical device
	* memory, so just add the sizes of the preceeding address regions to
	* get the offset to the new region.
	*
	* Currently, only the two first regions are addressed, and the
	* assumption is that all addresses will fall into either of those
	* two.
	*/
	if ((addr >= wl->part.reg.start) &&
	(addr < wl->part.reg.start + wl->part.reg.size))
	return addr - wl->part.reg.start + wl->part.mem.size;
	else
	return addr - wl->part.mem.start;
	}

	void wl1271_spi_reset(struct wl1271 *wl)
	{
	u8 *cmd;
	struct spi_transfer t;
	struct spi_message m;

	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
	if (!cmd) {
	wl1271_error("could not allocate cmd for spi reset");
	return;
	}

	memset(&t, 0, sizeof(t));
	spi_message_init(&m);

	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);

	t.tx_buf = cmd;
	t.len = WSPI_INIT_CMD_LEN;
	spi_message_add_tail(&t, &m);

	spi_sync(wl->spi, &m);

	wl1271_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
	}

	void wl1271_spi_init(struct wl1271 *wl)
	{
	u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
	struct spi_transfer t;
	struct spi_message m;

	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
	if (!cmd) {
	wl1271_error("could not allocate cmd for spi init");
	return;
	}

	memset(crc, 0, sizeof(crc));
	memset(&t, 0, sizeof(t));
	spi_message_init(&m);

	/*
	* Set WSPI_INIT_COMMAND
	* the data is being send from the MSB to LSB
	*/
	cmd[2] = 0xff;
	cmd[3] = 0xff;
	cmd[1] = WSPI_INIT_CMD_START \| WSPI_INIT_CMD_TX;
	cmd[0] = 0;
	cmd[7] = 0;
	cmd[6] \|= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
	cmd[6] \|= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;

	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
	cmd[5] \|= WSPI_INIT_CMD_DIS_FIXEDBUSY;
	else
	cmd[5] \|= WSPI_INIT_CMD_EN_FIXEDBUSY;

	cmd[5] \|= WSPI_INIT_CMD_IOD \| WSPI_INIT_CMD_IP \| WSPI_INIT_CMD_CS
	\| WSPI_INIT_CMD_WSPI \| WSPI_INIT_CMD_WS;

	crc[0] = cmd[1];
	crc[1] = cmd[0];
	crc[2] = cmd[7];
	crc[3] = cmd[6];
	crc[4] = cmd[5];

	cmd[4] \|= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
	cmd[4] \|= WSPI_INIT_CMD_END;

	t.tx_buf = cmd;
	t.len = WSPI_INIT_CMD_LEN;
	spi_message_add_tail(&t, &m);

	spi_sync(wl->spi, &m);

	wl1271_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
	}

	/* Set the SPI partitions to access the chip addresses
	*
	* To simplify driver code, a fixed (virtual) memory map is defined for
	* register and memory addresses. Because in the chipset, in different stages
	* of operation, those addresses will move around, an address translation
	* mechanism is required.
	*
	* There are four partitions (three memory and one register partition),
	* which are mapped to two different areas of the hardware memory.
	*
	* Virtual address
	* space
	*
	* \| \|
	* ...+----+--> mem.start
	* Physical address ... \| \|
	* space ... \| \| [PART_0]
	* ... \| \|
	* 00000000 <--+----+... ...+----+--> mem.start + mem.size
	* \| \| ... \| \|
	* \|MEM \| ... \| \|
	* \| \| ... \| \|
	* mem.size <--+----+... \| \| {unused area)
	* \| \| ... \| \|
	* \|REG \| ... \| \|
	* mem.size \| \| ... \| \|
	* + <--+----+... ...+----+--> reg.start
	* reg.size \| \| ... \| \|
	* \|MEM2\| ... \| \| [PART_1]
	* \| \| ... \| \|
	* ...+----+--> reg.start + reg.size
	* \| \|
	*
	*/
	int wl1271_set_partition(struct wl1271 *wl,
	struct wl1271_partition_set *p)
	{
	/* copy partition info */
	memcpy(&wl->part, p, sizeof(*p));

	wl1271_debug(DEBUG_SPI, "mem_start %08X mem_size %08X",
	p->mem.start, p->mem.size);
	wl1271_debug(DEBUG_SPI, "reg_start %08X reg_size %08X",
	p->reg.start, p->reg.size);
	wl1271_debug(DEBUG_SPI, "mem2_start %08X mem2_size %08X",
	p->mem2.start, p->mem2.size);
	wl1271_debug(DEBUG_SPI, "mem3_start %08X mem3_size %08X",
	p->mem3.start, p->mem3.size);

	/* write partition info to the chipset */
	wl1271_raw_write32(wl, HW_PART0_START_ADDR, p->mem.start);
	wl1271_raw_write32(wl, HW_PART0_SIZE_ADDR, p->mem.size);
	wl1271_raw_write32(wl, HW_PART1_START_ADDR, p->reg.start);
	wl1271_raw_write32(wl, HW_PART1_SIZE_ADDR, p->reg.size);
	wl1271_raw_write32(wl, HW_PART2_START_ADDR, p->mem2.start);
	wl1271_raw_write32(wl, HW_PART2_SIZE_ADDR, p->mem2.size);
	wl1271_raw_write32(wl, HW_PART3_START_ADDR, p->mem3.start);

	return 0;
	}

	#define WL1271_BUSY_WORD_TIMEOUT 1000

	/* FIXME: Check busy words, removed due to SPI bug */
	#if 0
	static void wl1271_spi_read_busy(struct wl1271 wl, void buf, size_t len)
	{
	struct spi_transfer t[1];
	struct spi_message m;
	u32 *busy_buf;
	int num_busy_bytes = 0;

	wl1271_info("spi read BUSY!");

	/*
	* Look for the non-busy word in the read buffer, and if found,
	* read in the remaining data into the buffer.
	*/
	busy_buf = (u32 *)buf;
	for (; (u32)busy_buf < (u32)buf + len; busy_buf++) {
	num_busy_bytes += sizeof(u32);
	if (*busy_buf & 0x1) {
	spi_message_init(&m);
	memset(t, 0, sizeof(t));
	memmove(buf, busy_buf, len - num_busy_bytes);
	t[0].rx_buf = buf + (len - num_busy_bytes);
	t[0].len = num_busy_bytes;
	spi_message_add_tail(&t[0], &m);
	spi_sync(wl->spi, &m);
	return;
	}
	}

	/*
	* Read further busy words from SPI until a non-busy word is
	* encountered, then read the data itself into the buffer.
	*/
	wl1271_info("spi read BUSY-polling needed!");

	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
	busy_buf = wl->buffer_busyword;
	while (num_busy_bytes) {
	num_busy_bytes--;
	spi_message_init(&m);
	memset(t, 0, sizeof(t));
	t[0].rx_buf = busy_buf;
	t[0].len = sizeof(u32);
	spi_message_add_tail(&t[0], &m);
	spi_sync(wl->spi, &m);

	if (*busy_buf & 0x1) {
	spi_message_init(&m);
	memset(t, 0, sizeof(t));
	t[0].rx_buf = buf;
	t[0].len = len;
	spi_message_add_tail(&t[0], &m);
	spi_sync(wl->spi, &m);
	return;
	}
	}

	/* The SPI bus is unresponsive, the read failed. */
	memset(buf, 0, len);
	wl1271_error("SPI read busy-word timeout!\n");
	}
	#endif

	void wl1271_spi_raw_read(struct wl1271 wl, int addr, void buf,
	size_t len, bool fixed)
	{
	struct spi_transfer t[3];
	struct spi_message m;
	u32 *busy_buf;
	u32 *cmd;

	cmd = &wl->buffer_cmd;
	busy_buf = wl->buffer_busyword;

	*cmd = 0;
	*cmd \|= WSPI_CMD_READ;
	*cmd \|= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
	*cmd \|= addr & WSPI_CMD_BYTE_ADDR;

	if (fixed)
	*cmd \|= WSPI_CMD_FIXED;

	spi_message_init(&m);
	memset(t, 0, sizeof(t));

	t[0].tx_buf = cmd;
	t[0].len = 4;
	spi_message_add_tail(&t[0], &m);

	/* Busy and non busy words read */
	t[1].rx_buf = busy_buf;
	t[1].len = WL1271_BUSY_WORD_LEN;
	spi_message_add_tail(&t[1], &m);

	t[2].rx_buf = buf;
	t[2].len = len;
	spi_message_add_tail(&t[2], &m);

	spi_sync(wl->spi, &m);

	/* FIXME: Check busy words, removed due to SPI bug */
	/* if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1))
	wl1271_spi_read_busy(wl, buf, len); */

	wl1271_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
	wl1271_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
	}

	void wl1271_spi_raw_write(struct wl1271 wl, int addr, void buf,
	size_t len, bool fixed)
	{
	struct spi_transfer t[2];
	struct spi_message m;
	u32 *cmd;

	cmd = &wl->buffer_cmd;

	*cmd = 0;
	*cmd \|= WSPI_CMD_WRITE;
	*cmd \|= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
	*cmd \|= addr & WSPI_CMD_BYTE_ADDR;

	if (fixed)
	*cmd \|= WSPI_CMD_FIXED;

	spi_message_init(&m);
	memset(t, 0, sizeof(t));

	t[0].tx_buf = cmd;
	t[0].len = sizeof(*cmd);
	spi_message_add_tail(&t[0], &m);

	t[1].tx_buf = buf;
	t[1].len = len;
	spi_message_add_tail(&t[1], &m);

	spi_sync(wl->spi, &m);

	wl1271_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
	wl1271_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
	}

	void wl1271_spi_read(struct wl1271 wl, int addr, void buf, size_t len,
	bool fixed)
	{
	int physical;

	physical = wl1271_translate_addr(wl, addr);

	wl1271_spi_raw_read(wl, physical, buf, len, fixed);
	}

	void wl1271_spi_write(struct wl1271 wl, int addr, void buf, size_t len,
	bool fixed)
	{
	int physical;

	physical = wl1271_translate_addr(wl, addr);

	wl1271_spi_raw_write(wl, physical, buf, len, fixed);
	}

	u32 wl1271_spi_read32(struct wl1271 *wl, int addr)
	{
	return wl1271_raw_read32(wl, wl1271_translate_addr(wl, addr));
	}

	void wl1271_spi_write32(struct wl1271 *wl, int addr, u32 val)
	{
	wl1271_raw_write32(wl, wl1271_translate_addr(wl, addr), val);
	}

	void wl1271_top_reg_write(struct wl1271 *wl, int addr, u16 val)
	{
	/* write address >> 1 + 0x30000 to OCP_POR_CTR */
	addr = (addr >> 1) + 0x30000;
	wl1271_spi_write32(wl, OCP_POR_CTR, addr);

	/* write value to OCP_POR_WDATA */
	wl1271_spi_write32(wl, OCP_DATA_WRITE, val);

	/* write 1 to OCP_CMD */
	wl1271_spi_write32(wl, OCP_CMD, OCP_CMD_WRITE);
	}

	u16 wl1271_top_reg_read(struct wl1271 *wl, int addr)
	{
	u32 val;
	int timeout = OCP_CMD_LOOP;

	/* write address >> 1 + 0x30000 to OCP_POR_CTR */
	addr = (addr >> 1) + 0x30000;
	wl1271_spi_write32(wl, OCP_POR_CTR, addr);

	/* write 2 to OCP_CMD */
	wl1271_spi_write32(wl, OCP_CMD, OCP_CMD_READ);

	/* poll for data ready */
	do {
	val = wl1271_spi_read32(wl, OCP_DATA_READ);
	timeout--;
	} while (!(val & OCP_READY_MASK) && timeout);

	if (!timeout) {
	wl1271_warning("Top register access timed out.");
	return 0xffff;
	}

	/* check data status and return if OK */
	if ((val & OCP_STATUS_MASK) == OCP_STATUS_OK)
	return val & 0xffff;
	else {
	wl1271_warning("Top register access returned error.");
	return 0xffff;
	}
	}