drivers/net/wireless/cw1200/cw1200_spi.c - kernel/bruno - Git at Google

 /*
  * Mac80211 SPI driver for ST-Ericsson CW1200 device
  *
  * Copyright (c) 2011, Sagrad Inc.
  * Author:  Solomon Peachy <speachy@sagrad.com>
  *
  * Based on cw1200_sdio.c
  * Copyright (c) 2010, ST-Ericsson
  * Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
  *
  * 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.
  */

 #include <linux/module.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <net/mac80211.h>

 #include <linux/spi/spi.h>
 #include <linux/device.h>

 #include "cw1200.h"
 #include "hwbus.h"
 #include <linux/platform_data/net-cw1200.h>
 #include "hwio.h"

 MODULE_AUTHOR("Solomon Peachy <speachy@sagrad.com>");
 MODULE_DESCRIPTION("mac80211 ST-Ericsson CW1200 SPI driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("spi:cw1200_wlan_spi");

 /* #define SPI_DEBUG */

 struct hwbus_priv {
 	struct spi_device	*func;
 	struct cw1200_common	*core;
 	const struct cw1200_platform_data_spi *pdata;
 	spinlock_t		lock; /* Serialize all bus operations */
 	wait_queue_head_t       wq;
 	int claimed;
 };

 #define SDIO_TO_SPI_ADDR(addr) ((addr & 0x1f)>>2)
 #define SET_WRITE 0x7FFF /* usage: and operation */
 #define SET_READ 0x8000  /* usage: or operation */

 /* Notes on byte ordering:
    LE:  B0 B1 B2 B3
    BE:  B3 B2 B1 B0

    Hardware expects 32-bit data to be written as 16-bit BE words:

    B1 B0 B3 B2
 */

 static int cw1200_spi_memcpy_fromio(struct hwbus_priv *self,
 				     unsigned int addr,
 				     void *dst, int count)
 {
 	int ret, i;
 	u16 regaddr;
 	struct spi_message      m;

 	struct spi_transfer     t_addr = {
 		.tx_buf         = &regaddr,
 		.len            = sizeof(regaddr),
 	};
 	struct spi_transfer     t_msg = {
 		.rx_buf         = dst,
 		.len            = count,
 	};

 	regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
 	regaddr |= SET_READ;
 	regaddr |= (count>>1);

 #ifdef SPI_DEBUG
 	pr_info("READ : %04d from 0x%02x (%04x)\n", count, addr, regaddr);
 #endif

 	/* Header is LE16 */
 	regaddr = cpu_to_le16(regaddr);

 	/* We have to byteswap if the SPI bus is limited to 8b operation
 	   or we are running on a Big Endian system
 	*/
 #if defined(__LITTLE_ENDIAN)
 	if (self->func->bits_per_word == 8)
 #endif
 		regaddr = swab16(regaddr);

 	spi_message_init(&m);
 	spi_message_add_tail(&t_addr, &m);
 	spi_message_add_tail(&t_msg, &m);
 	ret = spi_sync(self->func, &m);

 #ifdef SPI_DEBUG
 	pr_info("READ : ");
 	for (i = 0; i < t_addr.len; i++)
 		printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
 	printk(" : ");
 	for (i = 0; i < t_msg.len; i++)
 		printk("%02x ", ((u8 *)t_msg.rx_buf)[i]);
 	printk("\n");
 #endif

 	/* We have to byteswap if the SPI bus is limited to 8b operation
 	   or we are running on a Big Endian system
 	*/
 #if defined(__LITTLE_ENDIAN)
 	if (self->func->bits_per_word == 8)
 #endif
 	{
 		uint16_t *buf = (uint16_t *)dst;
 		for (i = 0; i < ((count + 1) >> 1); i++)
 			buf[i] = swab16(buf[i]);
 	}

 	return ret;
 }

 static int cw1200_spi_memcpy_toio(struct hwbus_priv *self,
 				   unsigned int addr,
 				   const void *src, int count)
 {
 	int rval, i;
 	u16 regaddr;
 	struct spi_transfer     t_addr = {
 		.tx_buf         = &regaddr,
 		.len            = sizeof(regaddr),
 	};
 	struct spi_transfer     t_msg = {
 		.tx_buf         = src,
 		.len            = count,
 	};
 	struct spi_message      m;

 	regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
 	regaddr &= SET_WRITE;
 	regaddr |= (count>>1);

 #ifdef SPI_DEBUG
 	pr_info("WRITE: %04d  to  0x%02x (%04x)\n", count, addr, regaddr);
 #endif

 	/* Header is LE16 */
 	regaddr = cpu_to_le16(regaddr);

 	/* We have to byteswap if the SPI bus is limited to 8b operation
 	   or we are running on a Big Endian system
 	*/
 #if defined(__LITTLE_ENDIAN)
 	if (self->func->bits_per_word == 8)
 #endif
 	{
 		uint16_t *buf = (uint16_t *)src;
 	        regaddr = swab16(regaddr);
 		for (i = 0; i < ((count + 1) >> 1); i++)
 			buf[i] = swab16(buf[i]);
 	}

 #ifdef SPI_DEBUG
 	pr_info("WRITE: ");
 	for (i = 0; i < t_addr.len; i++)
 		printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
 	printk(" : ");
 	for (i = 0; i < t_msg.len; i++)
 		printk("%02x ", ((u8 *)t_msg.tx_buf)[i]);
 	printk("\n");
 #endif

 	spi_message_init(&m);
 	spi_message_add_tail(&t_addr, &m);
 	spi_message_add_tail(&t_msg, &m);
 	rval = spi_sync(self->func, &m);

 #ifdef SPI_DEBUG
 	pr_info("WROTE: %d\n", m.actual_length);
 #endif

 #if defined(__LITTLE_ENDIAN)
 	/* We have to byteswap if the SPI bus is limited to 8b operation */
 	if (self->func->bits_per_word == 8)
 #endif
 	{
 		uint16_t *buf = (uint16_t *)src;
 		for (i = 0; i < ((count + 1) >> 1); i++)
 			buf[i] = swab16(buf[i]);
 	}
 	return rval;
 }

 static void cw1200_spi_lock(struct hwbus_priv *self)
 {
 	unsigned long flags;

 	DECLARE_WAITQUEUE(wait, current);

 	might_sleep();

 	add_wait_queue(&self->wq, &wait);
 	spin_lock_irqsave(&self->lock, flags);
 	while (1) {
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		if (!self->claimed)
 			break;
 		spin_unlock_irqrestore(&self->lock, flags);
 		schedule();
 		spin_lock_irqsave(&self->lock, flags);
 	}
 	set_current_state(TASK_RUNNING);
 	self->claimed = 1;
 	spin_unlock_irqrestore(&self->lock, flags);
 	remove_wait_queue(&self->wq, &wait);

 	return;
 }

 static void cw1200_spi_unlock(struct hwbus_priv *self)
 {
 	unsigned long flags;

 	spin_lock_irqsave(&self->lock, flags);
 	self->claimed = 0;
 	spin_unlock_irqrestore(&self->lock, flags);
 	wake_up(&self->wq);

 	return;
 }

 static irqreturn_t cw1200_spi_irq_handler(int irq, void *dev_id)
 {
 	struct hwbus_priv *self = dev_id;

 	if (self->core) {
 		cw1200_spi_lock(self);
 		cw1200_irq_handler(self->core);
 		cw1200_spi_unlock(self);
 		return IRQ_HANDLED;
 	} else {
 		return IRQ_NONE;
 	}
 }

 static int cw1200_spi_irq_subscribe(struct hwbus_priv *self)
 {
 	int ret;

 	pr_debug("SW IRQ subscribe\n");

 	ret = request_threaded_irq(self->func->irq, NULL,
 				   cw1200_spi_irq_handler,
 				   IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 				   "cw1200_wlan_irq", self);
 	if (WARN_ON(ret < 0))
 		goto exit;

 	ret = enable_irq_wake(self->func->irq);
 	if (WARN_ON(ret))
 		goto free_irq;

 	return 0;

 free_irq:
 	free_irq(self->func->irq, self);
 exit:
 	return ret;
 }

 static int cw1200_spi_irq_unsubscribe(struct hwbus_priv *self)
 {
 	int ret = 0;

 	pr_debug("SW IRQ unsubscribe\n");
 	disable_irq_wake(self->func->irq);
 	free_irq(self->func->irq, self);

 	return ret;
 }

 static int cw1200_spi_off(const struct cw1200_platform_data_spi *pdata)
 {
 	if (pdata->reset) {
 		gpio_set_value(pdata->reset, 0);
 		msleep(30); /* Min is 2 * CLK32K cycles */
 		gpio_free(pdata->reset);
 	}

 	if (pdata->power_ctrl)
 		pdata->power_ctrl(pdata, false);
 	if (pdata->clk_ctrl)
 		pdata->clk_ctrl(pdata, false);

 	return 0;
 }

 static int cw1200_spi_on(const struct cw1200_platform_data_spi *pdata)
 {
 	/* Ensure I/Os are pulled low */
 	if (pdata->reset) {
 		gpio_request(pdata->reset, "cw1200_wlan_reset");
 		gpio_direction_output(pdata->reset, 0);
 	}
 	if (pdata->powerup) {
 		gpio_request(pdata->powerup, "cw1200_wlan_powerup");
 		gpio_direction_output(pdata->powerup, 0);
 	}
 	if (pdata->reset || pdata->powerup)
 		msleep(10); /* Settle time? */

 	/* Enable 3v3 and 1v8 to hardware */
 	if (pdata->power_ctrl) {
 		if (pdata->power_ctrl(pdata, true)) {
 			pr_err("power_ctrl() failed!\n");
 			return -1;
 		}
 	}

 	/* Enable CLK32K */
 	if (pdata->clk_ctrl) {
 		if (pdata->clk_ctrl(pdata, true)) {
 			pr_err("clk_ctrl() failed!\n");
 			return -1;
 		}
 		msleep(10); /* Delay until clock is stable for 2 cycles */
 	}

 	/* Enable POWERUP signal */
 	if (pdata->powerup) {
 		gpio_set_value(pdata->powerup, 1);
 		msleep(250); /* or more..? */
 	}
 	/* Enable RSTn signal */
 	if (pdata->reset) {
 		gpio_set_value(pdata->reset, 1);
 		msleep(50); /* Or more..? */
 	}
 	return 0;
 }

 static size_t cw1200_spi_align_size(struct hwbus_priv *self, size_t size)
 {
 	return size & 1 ? size + 1 : size;
 }

 static int cw1200_spi_pm(struct hwbus_priv *self, bool suspend)
 {
 	return irq_set_irq_wake(self->func->irq, suspend);
 }

 static struct hwbus_ops cw1200_spi_hwbus_ops = {
 	.hwbus_memcpy_fromio	= cw1200_spi_memcpy_fromio,
 	.hwbus_memcpy_toio	= cw1200_spi_memcpy_toio,
 	.lock			= cw1200_spi_lock,
 	.unlock			= cw1200_spi_unlock,
 	.align_size		= cw1200_spi_align_size,
 	.power_mgmt		= cw1200_spi_pm,
 };

 /* Probe Function to be called by SPI stack when device is discovered */
 static int cw1200_spi_probe(struct spi_device *func)
 {
 	const struct cw1200_platform_data_spi *plat_data =
 		dev_get_platdata(&func->dev);
 	struct hwbus_priv *self;
 	int status;

 	/* Sanity check speed */
 	if (func->max_speed_hz > 52000000)
 		func->max_speed_hz = 52000000;
 	if (func->max_speed_hz < 1000000)
 		func->max_speed_hz = 1000000;

 	/* Fix up transfer size */
 	if (plat_data->spi_bits_per_word)
 		func->bits_per_word = plat_data->spi_bits_per_word;
 	if (!func->bits_per_word)
 		func->bits_per_word = 16;

 	/* And finally.. */
 	func->mode = SPI_MODE_0;

 	pr_info("cw1200_wlan_spi: Probe called (CS %d M %d BPW %d CLK %d)\n",
 		func->chip_select, func->mode, func->bits_per_word,
 		func->max_speed_hz);

 	if (cw1200_spi_on(plat_data)) {
 		pr_err("spi_on() failed!\n");
 		return -1;
 	}

 	if (spi_setup(func)) {
 		pr_err("spi_setup() failed!\n");
 		return -1;
 	}

 	self = devm_kzalloc(&func->dev, sizeof(*self), GFP_KERNEL);
 	if (!self) {
 		pr_err("Can't allocate SPI hwbus_priv.");
 		return -ENOMEM;
 	}

 	self->pdata = plat_data;
 	self->func = func;
 	spin_lock_init(&self->lock);

 	spi_set_drvdata(func, self);

 	init_waitqueue_head(&self->wq);

 	status = cw1200_spi_irq_subscribe(self);

 	status = cw1200_core_probe(&cw1200_spi_hwbus_ops,
 				   self, &func->dev, &self->core,
 				   self->pdata->ref_clk,
 				   self->pdata->macaddr,
 				   self->pdata->sdd_file,
 				   self->pdata->have_5ghz);

 	if (status) {
 		cw1200_spi_irq_unsubscribe(self);
 		cw1200_spi_off(plat_data);
 	}

 	return status;
 }

 /* Disconnect Function to be called by SPI stack when device is disconnected */
 static int cw1200_spi_disconnect(struct spi_device *func)
 {
 	struct hwbus_priv *self = spi_get_drvdata(func);

 	if (self) {
 		cw1200_spi_irq_unsubscribe(self);
 		if (self->core) {
 			cw1200_core_release(self->core);
 			self->core = NULL;
 		}
 	}
 	cw1200_spi_off(dev_get_platdata(&func->dev));

 	return 0;
 }

 #ifdef CONFIG_PM
 static int cw1200_spi_suspend(struct device *dev, pm_message_t state)
 {
 	struct hwbus_priv *self = spi_get_drvdata(to_spi_device(dev));

 	if (!cw1200_can_suspend(self->core))
 		return -EAGAIN;

 	/* XXX notify host that we have to keep CW1200 powered on? */
 	return 0;
 }

 static int cw1200_spi_resume(struct device *dev)
 {
 	return 0;
 }
 #endif

 static struct spi_driver spi_driver = {
 	.probe		= cw1200_spi_probe,
 	.remove		= cw1200_spi_disconnect,
 	.driver = {
 		.name		= "cw1200_wlan_spi",
 		.bus            = &spi_bus_type,
 		.owner          = THIS_MODULE,
 #ifdef CONFIG_PM
 		.suspend        = cw1200_spi_suspend,
 		.resume         = cw1200_spi_resume,
 #endif
 	},
 };

 module_spi_driver(spi_driver);
	/*
	* Mac80211 SPI driver for ST-Ericsson CW1200 device
	*
	* Copyright (c) 2011, Sagrad Inc.
	* Author: Solomon Peachy <speachy@sagrad.com>
	*
	* Based on cw1200_sdio.c
	* Copyright (c) 2010, ST-Ericsson
	* Author: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
	*
	* 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.
	*/

	#include <linux/module.h>
	#include <linux/gpio.h>
	#include <linux/delay.h>
	#include <linux/spinlock.h>
	#include <linux/interrupt.h>
	#include <net/mac80211.h>

	#include <linux/spi/spi.h>
	#include <linux/device.h>

	#include "cw1200.h"
	#include "hwbus.h"
	#include <linux/platform_data/net-cw1200.h>
	#include "hwio.h"

	MODULE_AUTHOR("Solomon Peachy <speachy@sagrad.com>");
	MODULE_DESCRIPTION("mac80211 ST-Ericsson CW1200 SPI driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("spi:cw1200_wlan_spi");

	/* #define SPI_DEBUG */

	struct hwbus_priv {
	struct spi_device *func;
	struct cw1200_common *core;
	const struct cw1200_platform_data_spi *pdata;
	spinlock_t lock; /* Serialize all bus operations */
	wait_queue_head_t wq;
	int claimed;
	};

	#define SDIO_TO_SPI_ADDR(addr) ((addr & 0x1f)>>2)
	#define SET_WRITE 0x7FFF /* usage: and operation */
	#define SET_READ 0x8000 /* usage: or operation */

	/* Notes on byte ordering:
	LE: B0 B1 B2 B3
	BE: B3 B2 B1 B0

	Hardware expects 32-bit data to be written as 16-bit BE words:

	B1 B0 B3 B2
	*/

	static int cw1200_spi_memcpy_fromio(struct hwbus_priv *self,
	unsigned int addr,
	void *dst, int count)
	{
	int ret, i;
	u16 regaddr;
	struct spi_message m;

	struct spi_transfer t_addr = {
	.tx_buf = &regaddr,
	.len = sizeof(regaddr),
	};
	struct spi_transfer t_msg = {
	.rx_buf = dst,
	.len = count,
	};

	regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
	regaddr \|= SET_READ;
	regaddr \|= (count>>1);

	#ifdef SPI_DEBUG
	pr_info("READ : %04d from 0x%02x (%04x)\n", count, addr, regaddr);
	#endif

	/* Header is LE16 */
	regaddr = cpu_to_le16(regaddr);

	/* We have to byteswap if the SPI bus is limited to 8b operation
	or we are running on a Big Endian system
	*/
	#if defined(__LITTLE_ENDIAN)
	if (self->func->bits_per_word == 8)
	#endif
	regaddr = swab16(regaddr);

	spi_message_init(&m);
	spi_message_add_tail(&t_addr, &m);
	spi_message_add_tail(&t_msg, &m);
	ret = spi_sync(self->func, &m);

	#ifdef SPI_DEBUG
	pr_info("READ : ");
	for (i = 0; i < t_addr.len; i++)
	printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
	printk(" : ");
	for (i = 0; i < t_msg.len; i++)
	printk("%02x ", ((u8 *)t_msg.rx_buf)[i]);
	printk("\n");
	#endif

	/* We have to byteswap if the SPI bus is limited to 8b operation
	or we are running on a Big Endian system
	*/
	#if defined(__LITTLE_ENDIAN)
	if (self->func->bits_per_word == 8)
	#endif
	{
	uint16_t buf = (uint16_t )dst;
	for (i = 0; i < ((count + 1) >> 1); i++)
	buf[i] = swab16(buf[i]);
	}

	return ret;
	}

	static int cw1200_spi_memcpy_toio(struct hwbus_priv *self,
	unsigned int addr,
	const void *src, int count)
	{
	int rval, i;
	u16 regaddr;
	struct spi_transfer t_addr = {
	.tx_buf = &regaddr,
	.len = sizeof(regaddr),
	};
	struct spi_transfer t_msg = {
	.tx_buf = src,
	.len = count,
	};
	struct spi_message m;

	regaddr = (SDIO_TO_SPI_ADDR(addr))<<12;
	regaddr &= SET_WRITE;
	regaddr \|= (count>>1);

	#ifdef SPI_DEBUG
	pr_info("WRITE: %04d to 0x%02x (%04x)\n", count, addr, regaddr);
	#endif

	/* Header is LE16 */
	regaddr = cpu_to_le16(regaddr);

	/* We have to byteswap if the SPI bus is limited to 8b operation
	or we are running on a Big Endian system
	*/
	#if defined(__LITTLE_ENDIAN)
	if (self->func->bits_per_word == 8)
	#endif
	{
	uint16_t buf = (uint16_t )src;
	regaddr = swab16(regaddr);
	for (i = 0; i < ((count + 1) >> 1); i++)
	buf[i] = swab16(buf[i]);
	}

	#ifdef SPI_DEBUG
	pr_info("WRITE: ");
	for (i = 0; i < t_addr.len; i++)
	printk("%02x ", ((u8 *)t_addr.tx_buf)[i]);
	printk(" : ");
	for (i = 0; i < t_msg.len; i++)
	printk("%02x ", ((u8 *)t_msg.tx_buf)[i]);
	printk("\n");
	#endif

	spi_message_init(&m);
	spi_message_add_tail(&t_addr, &m);
	spi_message_add_tail(&t_msg, &m);
	rval = spi_sync(self->func, &m);

	#ifdef SPI_DEBUG
	pr_info("WROTE: %d\n", m.actual_length);
	#endif

	#if defined(__LITTLE_ENDIAN)
	/* We have to byteswap if the SPI bus is limited to 8b operation */
	if (self->func->bits_per_word == 8)
	#endif
	{
	uint16_t buf = (uint16_t )src;
	for (i = 0; i < ((count + 1) >> 1); i++)
	buf[i] = swab16(buf[i]);
	}
	return rval;
	}

	static void cw1200_spi_lock(struct hwbus_priv *self)
	{
	unsigned long flags;

	DECLARE_WAITQUEUE(wait, current);

	might_sleep();

	add_wait_queue(&self->wq, &wait);
	spin_lock_irqsave(&self->lock, flags);
	while (1) {
	set_current_state(TASK_UNINTERRUPTIBLE);
	if (!self->claimed)
	break;
	spin_unlock_irqrestore(&self->lock, flags);
	schedule();
	spin_lock_irqsave(&self->lock, flags);
	}
	set_current_state(TASK_RUNNING);
	self->claimed = 1;
	spin_unlock_irqrestore(&self->lock, flags);
	remove_wait_queue(&self->wq, &wait);

	return;
	}

	static void cw1200_spi_unlock(struct hwbus_priv *self)
	{
	unsigned long flags;

	spin_lock_irqsave(&self->lock, flags);
	self->claimed = 0;
	spin_unlock_irqrestore(&self->lock, flags);
	wake_up(&self->wq);

	return;
	}

	static irqreturn_t cw1200_spi_irq_handler(int irq, void *dev_id)
	{
	struct hwbus_priv *self = dev_id;

	if (self->core) {
	cw1200_spi_lock(self);
	cw1200_irq_handler(self->core);
	cw1200_spi_unlock(self);
	return IRQ_HANDLED;
	} else {
	return IRQ_NONE;
	}
	}

	static int cw1200_spi_irq_subscribe(struct hwbus_priv *self)
	{
	int ret;

	pr_debug("SW IRQ subscribe\n");

	ret = request_threaded_irq(self->func->irq, NULL,
	cw1200_spi_irq_handler,
	IRQF_TRIGGER_HIGH \| IRQF_ONESHOT,
	"cw1200_wlan_irq", self);
	if (WARN_ON(ret < 0))
	goto exit;

	ret = enable_irq_wake(self->func->irq);
	if (WARN_ON(ret))
	goto free_irq;

	return 0;

	free_irq:
	free_irq(self->func->irq, self);
	exit:
	return ret;
	}

	static int cw1200_spi_irq_unsubscribe(struct hwbus_priv *self)
	{
	int ret = 0;

	pr_debug("SW IRQ unsubscribe\n");
	disable_irq_wake(self->func->irq);
	free_irq(self->func->irq, self);

	return ret;
	}

	static int cw1200_spi_off(const struct cw1200_platform_data_spi *pdata)
	{
	if (pdata->reset) {
	gpio_set_value(pdata->reset, 0);
	msleep(30); /* Min is 2 * CLK32K cycles */
	gpio_free(pdata->reset);
	}

	if (pdata->power_ctrl)
	pdata->power_ctrl(pdata, false);
	if (pdata->clk_ctrl)
	pdata->clk_ctrl(pdata, false);

	return 0;
	}

	static int cw1200_spi_on(const struct cw1200_platform_data_spi *pdata)
	{
	/* Ensure I/Os are pulled low */
	if (pdata->reset) {
	gpio_request(pdata->reset, "cw1200_wlan_reset");
	gpio_direction_output(pdata->reset, 0);
	}
	if (pdata->powerup) {
	gpio_request(pdata->powerup, "cw1200_wlan_powerup");
	gpio_direction_output(pdata->powerup, 0);
	}
	if (pdata->reset \|\| pdata->powerup)
	msleep(10); /* Settle time? */

	/* Enable 3v3 and 1v8 to hardware */
	if (pdata->power_ctrl) {
	if (pdata->power_ctrl(pdata, true)) {
	pr_err("power_ctrl() failed!\n");
	return -1;
	}
	}

	/* Enable CLK32K */
	if (pdata->clk_ctrl) {
	if (pdata->clk_ctrl(pdata, true)) {
	pr_err("clk_ctrl() failed!\n");
	return -1;
	}
	msleep(10); /* Delay until clock is stable for 2 cycles */
	}

	/* Enable POWERUP signal */
	if (pdata->powerup) {
	gpio_set_value(pdata->powerup, 1);
	msleep(250); /* or more..? */
	}
	/* Enable RSTn signal */
	if (pdata->reset) {
	gpio_set_value(pdata->reset, 1);
	msleep(50); /* Or more..? */
	}
	return 0;
	}

	static size_t cw1200_spi_align_size(struct hwbus_priv *self, size_t size)
	{
	return size & 1 ? size + 1 : size;
	}

	static int cw1200_spi_pm(struct hwbus_priv *self, bool suspend)
	{
	return irq_set_irq_wake(self->func->irq, suspend);
	}

	static struct hwbus_ops cw1200_spi_hwbus_ops = {
	.hwbus_memcpy_fromio = cw1200_spi_memcpy_fromio,
	.hwbus_memcpy_toio = cw1200_spi_memcpy_toio,
	.lock = cw1200_spi_lock,
	.unlock = cw1200_spi_unlock,
	.align_size = cw1200_spi_align_size,
	.power_mgmt = cw1200_spi_pm,
	};

	/* Probe Function to be called by SPI stack when device is discovered */
	static int cw1200_spi_probe(struct spi_device *func)
	{
	const struct cw1200_platform_data_spi *plat_data =
	dev_get_platdata(&func->dev);
	struct hwbus_priv *self;
	int status;

	/* Sanity check speed */
	if (func->max_speed_hz > 52000000)
	func->max_speed_hz = 52000000;
	if (func->max_speed_hz < 1000000)
	func->max_speed_hz = 1000000;

	/* Fix up transfer size */
	if (plat_data->spi_bits_per_word)
	func->bits_per_word = plat_data->spi_bits_per_word;
	if (!func->bits_per_word)
	func->bits_per_word = 16;

	/* And finally.. */
	func->mode = SPI_MODE_0;

	pr_info("cw1200_wlan_spi: Probe called (CS %d M %d BPW %d CLK %d)\n",
	func->chip_select, func->mode, func->bits_per_word,
	func->max_speed_hz);

	if (cw1200_spi_on(plat_data)) {
	pr_err("spi_on() failed!\n");
	return -1;
	}

	if (spi_setup(func)) {
	pr_err("spi_setup() failed!\n");
	return -1;
	}

	self = devm_kzalloc(&func->dev, sizeof(*self), GFP_KERNEL);
	if (!self) {
	pr_err("Can't allocate SPI hwbus_priv.");
	return -ENOMEM;
	}

	self->pdata = plat_data;
	self->func = func;
	spin_lock_init(&self->lock);

	spi_set_drvdata(func, self);

	init_waitqueue_head(&self->wq);

	status = cw1200_spi_irq_subscribe(self);

	status = cw1200_core_probe(&cw1200_spi_hwbus_ops,
	self, &func->dev, &self->core,
	self->pdata->ref_clk,
	self->pdata->macaddr,
	self->pdata->sdd_file,
	self->pdata->have_5ghz);

	if (status) {
	cw1200_spi_irq_unsubscribe(self);
	cw1200_spi_off(plat_data);
	}

	return status;
	}

	/* Disconnect Function to be called by SPI stack when device is disconnected */
	static int cw1200_spi_disconnect(struct spi_device *func)
	{
	struct hwbus_priv *self = spi_get_drvdata(func);

	if (self) {
	cw1200_spi_irq_unsubscribe(self);
	if (self->core) {
	cw1200_core_release(self->core);
	self->core = NULL;
	}
	}
	cw1200_spi_off(dev_get_platdata(&func->dev));

	return 0;
	}

	#ifdef CONFIG_PM
	static int cw1200_spi_suspend(struct device *dev, pm_message_t state)
	{
	struct hwbus_priv *self = spi_get_drvdata(to_spi_device(dev));

	if (!cw1200_can_suspend(self->core))
	return -EAGAIN;

	/* XXX notify host that we have to keep CW1200 powered on? */
	return 0;
	}

	static int cw1200_spi_resume(struct device *dev)
	{
	return 0;
	}
	#endif

	static struct spi_driver spi_driver = {
	.probe = cw1200_spi_probe,
	.remove = cw1200_spi_disconnect,
	.driver = {
	.name = "cw1200_wlan_spi",
	.bus = &spi_bus_type,
	.owner = THIS_MODULE,
	#ifdef CONFIG_PM
	.suspend = cw1200_spi_suspend,
	.resume = cw1200_spi_resume,
	#endif
	},
	};

	module_spi_driver(spi_driver);