tegra bluesleep: Bluetooth active power management driver

A new driver is implemented to actively manage the bluetooth module
power. bluesleep also tries to manage the power of the transport used.

Two signals (GPIOs) are used to manage the power events.

BT_WAKE  : signal from HOST to BT chip to intimate BT chip can sleep.
HOST_WAKE: signal from BT chip to HOST to intimate HOST should wakeup/
activate the transport modules required for BT communication.

Bug 791669, 773186

(cherry picked from commit 111f4ccd3c4cfde2fa52ae4c0c56a2288c3af3a8)

Original-Change-Id: Iff1e81bb22d9bd43113f7cdd01329da3ae852a15
Reviewed-on: http://git-master/r/19858
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Tested-by: Bharat Nihalani <bnihalani@nvidia.com>

Rebase-Id: R1eca7f2f51475daf6104e71e90ad5db1213fa6ea

3 files changed, 837 insertions, 0 deletions

diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
index 11b41fd40c27..adf975635488 100644
--- a/drivers/bluetooth/Kconfig
+++ b/drivers/bluetooth/Kconfig
@@ -93,6 +93,16 @@ config BT_HCIBCM203X
 	  Say Y here to compile support for HCI BCM203x devices into the
 	  kernel or say M to compile it as module (bcm203x).
 
+config BT_BLUESLEEP
+        tristate "Bluesleep driver support"
+        help
+          Bluetooth Bluesleep Driver.
+          This driver provides the dynamic active power saving mechanism for
+          bluetooth radio devices.
+
+          Say Y here to compile support for bluesleep support into the kernel
+          or say M to compile it as module (bluesleep).
+
 config BT_HCIBPA10X
 	tristate "HCI BPA10x USB driver"
 	depends on USB
diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
index f4460f4f4b78..4c2f9d0051be 100644
--- a/drivers/bluetooth/Makefile
+++ b/drivers/bluetooth/Makefile
@@ -4,6 +4,7 @@
 
 obj-$(CONFIG_BT_HCIVHCI)	+= hci_vhci.o
 obj-$(CONFIG_BT_HCIUART)	+= hci_uart.o
+obj-$(CONFIG_BT_BLUESLEEP)	+= bluesleep.o
 obj-$(CONFIG_BT_HCIBCM203X)	+= bcm203x.o
 obj-$(CONFIG_BT_HCIBPA10X)	+= bpa10x.o
 obj-$(CONFIG_BT_HCIBFUSB)	+= bfusb.o
diff --git a/drivers/bluetooth/bluesleep.c b/drivers/bluetooth/bluesleep.c
new file mode 100644
index 000000000000..fb9953aa190a
--- /dev/null
+++ b/drivers/bluetooth/bluesleep.c
@@ -0,0 +1,826 @@
+/*
+ * 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.
+ *
+ * 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
+ *
+ * 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.
+ *
+ * Copyright (C) 2006-2007 - Motorola
+ * Copyright (c) 2008-2009, Code Aurora Forum. All rights reserved.
+ *
+ *  Date         Author           Comment
+ * -----------  --------------   --------------------------------
+ * 2006-Apr-28  Motorola         The kernel module for running the Bluetooth(R)
+ *                               Sleep-Mode Protocol from the Host side
+ * 2006-Sep-08  Motorola         Added workqueue for handling sleep work.
+ * 2007-Jan-24  Motorola         Added mbm_handle_ioi() call to ISR.
+ * 2009-Aug-10  Motorola         Changed "add_timer" to "mod_timer" to solve
+ *                               race when flurry of queued work comes in.
+*/
+
+#include <linux/module.h>       /* kernel module definitions */
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/proc_fs.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/uaccess.h>
+#include <linux/version.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+
+#include <linux/irq.h>
+#include <linux/ioport.h>
+#include <linux/param.h>
+#include <linux/bitops.h>
+#include <linux/termios.h>
+#include <linux/wakelock.h>
+#include <mach/gpio.h>
+#include <linux/serial_core.h>
+#include <linux/tegra_uart.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h> /* event notifications */
+#include "hci_uart.h"
+
+#define BT_SLEEP_DBG
+#ifndef BT_SLEEP_DBG
+#define BT_DBG(fmt, arg...)
+#endif
+/*
+ * Defines
+ */
+
+#define VERSION	 "1.1"
+#define PROC_DIR	"bluetooth/sleep"
+
+#define POLARITY_LOW 0
+#define POLARITY_HIGH 1
+
+struct bluesleep_info {
+	unsigned host_wake;
+	unsigned ext_wake;
+	unsigned host_wake_irq;
+	struct uart_port *uport;
+	struct wake_lock wake_lock;
+	int irq_polarity;
+	int has_ext_wake;
+};
+
+/* work function */
+static void bluesleep_sleep_work(struct work_struct *work);
+
+/* work queue */
+DECLARE_DELAYED_WORK(sleep_workqueue, bluesleep_sleep_work);
+
+/* Macros for handling sleep work */
+#define bluesleep_rx_busy()     schedule_delayed_work(&sleep_workqueue, 0)
+#define bluesleep_tx_busy()     schedule_delayed_work(&sleep_workqueue, 0)
+#define bluesleep_rx_idle()     schedule_delayed_work(&sleep_workqueue, 0)
+#define bluesleep_tx_idle()     schedule_delayed_work(&sleep_workqueue, 0)
+
+/* 10 second timeout */
+#define TX_TIMER_INTERVAL  10
+
+/* state variable names and bit positions */
+#define BT_PROTO	 0x01
+#define BT_TXDATA	 0x02
+#define BT_ASLEEP	 0x04
+#define BT_EXT_WAKE	0x08
+
+/* global pointer to a single hci device. */
+static struct hci_dev *bluesleep_hdev;
+
+static struct bluesleep_info *bsi;
+
+/* module usage */
+static atomic_t open_count = ATOMIC_INIT(1);
+
+/*
+ * Local function prototypes
+ */
+static int bluesleep_hci_event(struct notifier_block *this,
+			unsigned long event, void *data);
+static int bluesleep_start(void);
+static void bluesleep_stop(void);
+
+/*
+ * Global variables
+ */
+/** Global state flags */
+static unsigned long flags;
+
+/** Tasklet to respond to change in hostwake line */
+static struct tasklet_struct hostwake_task;
+
+/** Transmission timer */
+static void bluesleep_tx_timer_expire(unsigned long data);
+static DEFINE_TIMER(tx_timer, bluesleep_tx_timer_expire, 0, 0);
+
+/** Lock for state transitions */
+static spinlock_t rw_lock;
+
+/** Notifier block for HCI events */
+struct notifier_block hci_event_nblock = {
+	.notifier_call = bluesleep_hci_event,
+};
+
+struct proc_dir_entry *bluetooth_dir, *sleep_dir;
+
+/*
+ * Local functions
+ */
+static void hsuart_power(int on)
+{
+	if (on) {
+		tegra_uart_request_clock_on(bsi->uport);
+		tegra_uart_set_mctrl(bsi->uport, TIOCM_RTS);
+	} else {
+		tegra_uart_set_mctrl(bsi->uport, 0);
+		tegra_uart_request_clock_off(bsi->uport);
+	}
+}
+
+/**
+ * @return 1 if the Host can go to sleep, 0 otherwise.
+ */
+int bluesleep_can_sleep(void)
+{
+	/* check if WAKE_BT_GPIO and BT_WAKE_GPIO are both deasserted */
+	return ((gpio_get_value(bsi->host_wake) != bsi->irq_polarity) &&
+		(!test_bit(BT_EXT_WAKE, &flags)) &&
+		(bsi->uport != NULL));
+}
+
+void bluesleep_sleep_wakeup(void)
+{
+	if (test_bit(BT_ASLEEP, &flags)) {
+		BT_DBG("waking up...");
+		wake_lock(&bsi->wake_lock);
+		/* Start the timer */
+		mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL * HZ));
+		if (bsi->has_ext_wake == 1)
+			gpio_set_value(bsi->ext_wake, 1);
+		set_bit(BT_EXT_WAKE, &flags);
+		clear_bit(BT_ASLEEP, &flags);
+		/*Activating UART */
+		hsuart_power(1);
+	}
+}
+
+/**
+ * @brief@  main sleep work handling function which update the flags
+ * and activate and deactivate UART ,check FIFO.
+ */
+static void bluesleep_sleep_work(struct work_struct *work)
+{
+	if (bluesleep_can_sleep()) {
+		/* already asleep, this is an error case */
+		if (test_bit(BT_ASLEEP, &flags)) {
+			BT_DBG("already asleep");
+			return;
+		}
+
+		if (tegra_uart_is_tx_empty(bsi->uport)) {
+			BT_DBG("going to sleep...");
+			set_bit(BT_ASLEEP, &flags);
+			/*Deactivating UART */
+			hsuart_power(0);
+			/* UART clk is not turned off immediately. Release
+			 * wakelock after 500 ms.
+			 */
+			wake_lock_timeout(&bsi->wake_lock, HZ / 2);
+		} else {
+			mod_timer(&tx_timer, jiffies + TX_TIMER_INTERVAL * HZ);
+			return;
+		}
+	} else if (!test_bit(BT_EXT_WAKE, &flags)
+			&& !test_bit(BT_ASLEEP, &flags)) {
+		mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL * HZ));
+		if (bsi->has_ext_wake == 1)
+			gpio_set_value(bsi->ext_wake, 1);
+		set_bit(BT_EXT_WAKE, &flags);
+	} else {
+		bluesleep_sleep_wakeup();
+	}
+}
+
+/**
+ * A tasklet function that runs in tasklet context and reads the value
+ * of the HOST_WAKE GPIO pin and further defer the work.
+ * @param data Not used.
+ */
+static void bluesleep_hostwake_task(unsigned long data)
+{
+	BT_DBG("hostwake line change");
+
+	spin_lock(&rw_lock);
+	if ((gpio_get_value(bsi->host_wake) == bsi->irq_polarity))
+		bluesleep_rx_busy();
+	else
+		bluesleep_rx_idle();
+	spin_unlock(&rw_lock);
+
+}
+
+/**
+ * Handles proper timer action when outgoing data is delivered to the
+ * HCI line discipline. Sets BT_TXDATA.
+ */
+static void bluesleep_outgoing_data(void)
+{
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&rw_lock, irq_flags);
+	/* log data passing by */
+	set_bit(BT_TXDATA, &flags);
+	/* if the tx side is sleeping... */
+	if (!test_bit(BT_EXT_WAKE, &flags)) {
+		BT_DBG("tx was sleeping");
+		bluesleep_sleep_wakeup();
+	}
+	spin_unlock_irqrestore(&rw_lock, irq_flags);
+}
+
+/**
+ * Handles HCI device events.
+ * @param this Not used.
+ * @param event The event that occurred.
+ * @param data The HCI device associated with the event.
+ * @return <code>NOTIFY_DONE</code>.
+ */
+static int bluesleep_hci_event(struct notifier_block *this,
+				unsigned long event, void *data)
+{
+	struct hci_dev *hdev = (struct hci_dev *) data;
+	struct hci_uart *hu;
+	struct uart_state *state;
+
+	if (!hdev)
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case HCI_DEV_REG:
+		if (!bluesleep_hdev) {
+			bluesleep_hdev = hdev;
+			hu  = (struct hci_uart *) hdev->driver_data;
+			state = (struct uart_state *) hu->tty->driver_data;
+			bsi->uport = state->uart_port;
+			/* if bluetooth started, start bluesleep*/
+			bluesleep_start();
+		}
+		break;
+	case HCI_DEV_UNREG:
+		bluesleep_hdev = NULL;
+		bsi->uport = NULL;
+		/* if bluetooth stopped, stop bluesleep also */
+		bluesleep_stop();
+		break;
+	case HCI_DEV_WRITE:
+		bluesleep_outgoing_data();
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+/**
+ * Handles transmission timer expiration.
+ * @param data Not used.
+ */
+static void bluesleep_tx_timer_expire(unsigned long data)
+{
+	unsigned long irq_flags;
+
+	BT_DBG("Tx timer expired");
+
+	spin_lock_irqsave(&rw_lock, irq_flags);
+
+	/* were we silent during the last timeout? */
+	if (!test_bit(BT_TXDATA, &flags)) {
+		BT_DBG("Tx has been idle");
+		if (bsi->has_ext_wake == 1)
+			gpio_set_value(bsi->ext_wake, 0);
+		clear_bit(BT_EXT_WAKE, &flags);
+		bluesleep_tx_idle();
+	} else {
+		BT_DBG("Tx data during last period");
+		mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL*HZ));
+	}
+
+	/* clear the incoming data flag */
+	clear_bit(BT_TXDATA, &flags);
+
+	spin_unlock_irqrestore(&rw_lock, irq_flags);
+}
+
+/**
+ * Schedules a tasklet to run when receiving an interrupt on the
+ * <code>HOST_WAKE</code> GPIO pin.
+ * @param irq Not used.
+ * @param dev_id Not used.
+ */
+static irqreturn_t bluesleep_hostwake_isr(int irq, void *dev_id)
+{
+	/* schedule a tasklet to handle the change in the host wake line */
+	tasklet_schedule(&hostwake_task);
+	return IRQ_HANDLED;
+}
+
+/**
+ * Starts the Sleep-Mode Protocol on the Host.
+ * @return On success, 0. On error, -1, and <code>errno</code> is set
+ * appropriately.
+ */
+static int bluesleep_start(void)
+{
+	int retval;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&rw_lock, irq_flags);
+	if (test_bit(BT_PROTO, &flags)) {
+		spin_unlock_irqrestore(&rw_lock, irq_flags);
+		return 0;
+	}
+	spin_unlock_irqrestore(&rw_lock, irq_flags);
+
+	if (!atomic_dec_and_test(&open_count)) {
+		atomic_inc(&open_count);
+		return -EBUSY;
+	}
+
+	/* start the timer */
+	mod_timer(&tx_timer, jiffies + (TX_TIMER_INTERVAL * HZ));
+
+	/* assert BT_WAKE */
+	if (bsi->has_ext_wake == 1)
+		gpio_set_value(bsi->ext_wake, 1);
+	set_bit(BT_EXT_WAKE, &flags);
+
+	if (bsi->irq_polarity == POLARITY_LOW) {
+		retval = request_irq(bsi->host_wake_irq, bluesleep_hostwake_isr,
+				IRQF_DISABLED | IRQF_TRIGGER_FALLING,
+				"bluetooth hostwake", NULL);
+	} else 	{
+		retval = request_irq(bsi->host_wake_irq, bluesleep_hostwake_isr,
+				IRQF_DISABLED | IRQF_TRIGGER_RISING,
+				"bluetooth hostwake", NULL);
+	}
+	if (retval  < 0) {
+		BT_ERR("Couldn't acquire BT_HOST_WAKE IRQ");
+		goto fail;
+	}
+
+	retval = enable_irq_wake(bsi->host_wake_irq);
+	if (retval < 0) {
+		BT_ERR("Couldn't enable BT_HOST_WAKE as wakeup interrupt");
+		free_irq(bsi->host_wake_irq, NULL);
+		goto fail;
+	}
+	set_bit(BT_PROTO, &flags);
+	wake_lock(&bsi->wake_lock);
+	return 0;
+fail:
+	del_timer(&tx_timer);
+	atomic_inc(&open_count);
+
+	return retval;
+}
+
+/**
+ * Stops the Sleep-Mode Protocol on the Host.
+ */
+static void bluesleep_stop(void)
+{
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&rw_lock, irq_flags);
+	if (!test_bit(BT_PROTO, &flags)) {
+		spin_unlock_irqrestore(&rw_lock, irq_flags);
+		return;
+	}
+	/* assert BT_WAKE */
+	if (bsi->has_ext_wake == 1)
+		gpio_set_value(bsi->ext_wake, 1);
+	set_bit(BT_EXT_WAKE, &flags);
+	del_timer(&tx_timer);
+	clear_bit(BT_PROTO, &flags);
+
+	if (test_bit(BT_ASLEEP, &flags)) {
+		clear_bit(BT_ASLEEP, &flags);
+		hsuart_power(1);
+	}
+
+	atomic_inc(&open_count);
+	spin_unlock_irqrestore(&rw_lock, irq_flags);
+
+	if (disable_irq_wake(bsi->host_wake_irq))
+		BT_ERR("Couldn't disable hostwake IRQ wakeup mode\n");
+	free_irq(bsi->host_wake_irq, NULL);
+	wake_lock_timeout(&bsi->wake_lock, HZ / 2);
+}
+/**
+ * Read the <code>BT_WAKE</code> GPIO pin value via the proc interface.
+ * When this function returns, <code>page</code> will contain a 1 if the
+ * pin is high, 0 otherwise.
+ * @param page Buffer for writing data.
+ * @param start Not used.
+ * @param offset Not used.
+ * @param count Not used.
+ * @param eof Whether or not there is more data to be read.
+ * @param data Not used.
+ * @return The number of bytes written.
+ */
+static int bluepower_read_proc_btwake(char *page, char **start, off_t offset,
+					int count, int *eof, void *data)
+{
+	*eof = 1;
+	return sprintf(page, "btwake:%u\n",test_bit(BT_EXT_WAKE, &flags));
+}
+
+/**
+ * Write the <code>BT_WAKE</code> GPIO pin value via the proc interface.
+ * @param file Not used.
+ * @param buffer The buffer to read from.
+ * @param count The number of bytes to be written.
+ * @param data Not used.
+ * @return On success, the number of bytes written. On error, -1, and
+ * <code>errno</code> is set appropriately.
+ */
+static int bluepower_write_proc_btwake(struct file *file, const char *buffer,
+					unsigned long count, void *data)
+{
+	char *buf;
+
+	if (count < 1)
+		return -EINVAL;
+
+	buf = kmalloc(count, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	if (copy_from_user(buf, buffer, count)) {
+		kfree(buf);
+		return -EFAULT;
+	}
+	if (buf[0] == '0') {
+		if (bsi->has_ext_wake == 1)
+			gpio_set_value(bsi->ext_wake, 0);
+		clear_bit(BT_EXT_WAKE, &flags);
+	} else if (buf[0] == '1') {
+		if (bsi->has_ext_wake == 1)
+			gpio_set_value(bsi->ext_wake, 1);
+		set_bit(BT_EXT_WAKE, &flags);
+	} else {
+		kfree(buf);
+		return -EINVAL;
+	}
+
+	kfree(buf);
+	return count;
+}
+
+/**
+ * Read the <code>BT_HOST_WAKE</code> GPIO pin value via the proc interface.
+ * When this function returns, <code>page</code> will contain a 1 if the pin
+ * is high, 0 otherwise.
+ * @param page Buffer for writing data.
+ * @param start Not used.
+ * @param offset Not used.
+ * @param count Not used.
+ * @param eof Whether or not there is more data to be read.
+ * @param data Not used.
+ * @return The number of bytes written.
+ */
+static int bluepower_read_proc_hostwake(char *page, char **start, off_t offset,
+					int count, int *eof, void *data)
+{
+	*eof = 1;
+	return sprintf(page, "hostwake: %u\n", gpio_get_value(bsi->host_wake));
+}
+
+
+/**
+ * Read the low-power status of the Host via the proc interface.
+ * When this function returns, <code>page</code> contains a 1 if the Host
+ * is asleep, 0 otherwise.
+ * @param page Buffer for writing data.
+ * @param start Not used.
+ * @param offset Not used.
+ * @param count Not used.
+ * @param eof Whether or not there is more data to be read.
+ * @param data Not used.
+ * @return The number of bytes written.
+ */
+static int bluesleep_read_proc_asleep(char *page, char **start, off_t offset,
+					int count, int *eof, void *data)
+{
+	unsigned int asleep;
+
+	asleep = test_bit(BT_ASLEEP, &flags) ? 1 : 0;
+	*eof = 1;
+	return sprintf(page, "asleep: %u\n", asleep);
+}
+
+/**
+ * Read the low-power protocol being used by the Host via the proc interface.
+ * When this function returns, <code>page</code> will contain a 1 if the Host
+ * is using the Sleep Mode Protocol, 0 otherwise.
+ * @param page Buffer for writing data.
+ * @param start Not used.
+ * @param offset Not used.
+ * @param count Not used.
+ * @param eof Whether or not there is more data to be read.
+ * @param data Not used.
+ * @return The number of bytes written.
+ */
+static int bluesleep_read_proc_proto(char *page, char **start, off_t offset,
+					int count, int *eof, void *data)
+{
+	unsigned int proto;
+
+	proto = test_bit(BT_PROTO, &flags) ? 1 : 0;
+	*eof = 1;
+	return sprintf(page, "proto: %u\n", proto);
+}
+
+/**
+ * Modify the low-power protocol used by the Host via the proc interface.
+ * @param file Not used.
+ * @param buffer The buffer to read from.
+ * @param count The number of bytes to be written.
+ * @param data Not used.
+ * @return On success, the number of bytes written. On error, -1, and
+ * <code>errno</code> is set appropriately.
+ */
+static int bluesleep_write_proc_proto(struct file *file, const char *buffer,
+					unsigned long count, void *data)
+{
+	char proto;
+
+	if (count < 1)
+		return -EINVAL;
+
+	if (copy_from_user(&proto, buffer, 1))
+		return -EFAULT;
+
+	if (proto == '0')
+		bluesleep_stop();
+	else
+		bluesleep_start();
+
+	/* claim that we wrote everything */
+	return count;
+}
+
+
+static int __init bluesleep_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *res;
+
+	bsi = kzalloc(sizeof(struct bluesleep_info), GFP_KERNEL);
+	if (!bsi)
+		return -ENOMEM;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_IO,
+				"gpio_host_wake");
+	if (!res) {
+		BT_ERR("couldn't find host_wake gpio\n");
+		ret = -ENODEV;
+		goto free_bsi;
+	}
+	bsi->host_wake = res->start;
+
+	ret = gpio_request(bsi->host_wake, "bt_host_wake");
+	if (ret)
+		goto free_bsi;
+
+	/* configure host_wake as input */
+	ret = gpio_direction_input(bsi->host_wake);
+	if (ret < 0) {
+		pr_err("gpio-keys: failed to configure input"
+				" direction for GPIO %d, error %d\n",
+				bsi->host_wake, ret);
+		gpio_free(bsi->host_wake);
+		goto free_bsi;
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_IO,
+				"gpio_ext_wake");
+
+	if (!res)
+		bsi->has_ext_wake = 0;
+	else
+		bsi->has_ext_wake = 1;
+
+	if (bsi->has_ext_wake) {
+		bsi->ext_wake = res->start;
+		ret = gpio_request(bsi->ext_wake, "bt_ext_wake");
+		if (ret)
+			goto free_bt_host_wake;
+
+		/* configure ext_wake as output mode*/
+		ret = gpio_direction_output(bsi->ext_wake, 1);
+		if (ret < 0) {
+			pr_err("gpio-keys: failed to configure output"
+				" direction for GPIO %d, error %d\n",
+				  bsi->ext_wake, ret);
+			gpio_free(bsi->ext_wake);
+			goto free_bt_host_wake;
+		}
+	} else
+		set_bit(BT_EXT_WAKE, &flags);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
+						"host_wake");
+	if (!res) {
+		BT_ERR("couldn't find host_wake irq\n");
+		ret = -ENODEV;
+		goto free_bt_host_wake;
+	}
+	bsi->host_wake_irq = res->start;
+	if (bsi->host_wake_irq < 0) {
+		BT_ERR("couldn't find host_wake irq\n");
+		ret = -ENODEV;
+		goto free_bt_ext_wake;
+	}
+	if (res->flags & IORESOURCE_IRQ_LOWEDGE)
+		bsi->irq_polarity = POLARITY_LOW;/*low edge (falling edge)*/
+	else
+		bsi->irq_polarity = POLARITY_HIGH;/*anything else*/
+
+	wake_lock_init(&bsi->wake_lock, WAKE_LOCK_SUSPEND, "bluesleep");
+
+	return 0;
+
+free_bt_ext_wake:
+	gpio_free(bsi->ext_wake);
+free_bt_host_wake:
+	gpio_free(bsi->host_wake);
+free_bsi:
+	kfree(bsi);
+	return ret;
+}
+
+static int bluesleep_remove(struct platform_device *pdev)
+{
+	gpio_free(bsi->host_wake);
+	gpio_free(bsi->ext_wake);
+	wake_lock_destroy(&bsi->wake_lock);
+	kfree(bsi);
+	return 0;
+}
+
+static struct platform_driver bluesleep_driver = {
+	.probe = bluesleep_probe,
+	.remove = bluesleep_remove,
+	.driver = {
+		.name = "bluesleep",
+		.owner = THIS_MODULE,
+	},
+};
+/**
+ * Initializes the module.
+ * @return On success, 0. On error, -1, and <code>errno</code> is set
+ * appropriately.
+ */
+static int __init bluesleep_init(void)
+{
+	int retval;
+	struct proc_dir_entry *ent;
+
+	BT_INFO("BlueSleep Mode Driver Ver %s", VERSION);
+
+	retval = platform_driver_register(&bluesleep_driver);
+	if (retval)
+		return retval;
+
+	bluesleep_hdev = NULL;
+
+	bluetooth_dir = proc_mkdir("bluetooth", NULL);
+	if (bluetooth_dir == NULL) {
+		BT_ERR("Unable to create /proc/bluetooth directory");
+		return -ENOMEM;
+	}
+
+	sleep_dir = proc_mkdir("sleep", bluetooth_dir);
+	if (sleep_dir == NULL) {
+		BT_ERR("Unable to create /proc/%s directory", PROC_DIR);
+		return -ENOMEM;
+	}
+
+	/* Creating read/write "btwake" entry */
+	ent = create_proc_entry("btwake", 0, sleep_dir);
+	if (ent == NULL) {
+		BT_ERR("Unable to create /proc/%s/btwake entry", PROC_DIR);
+		retval = -ENOMEM;
+		goto fail;
+	}
+	ent->read_proc = bluepower_read_proc_btwake;
+	ent->write_proc = bluepower_write_proc_btwake;
+
+	/* read only proc entries */
+	if (create_proc_read_entry("hostwake", 0, sleep_dir,
+				bluepower_read_proc_hostwake, NULL) == NULL) {
+		BT_ERR("Unable to create /proc/%s/hostwake entry", PROC_DIR);
+		retval = -ENOMEM;
+		goto fail;
+	}
+
+	/* read/write proc entries */
+	ent = create_proc_entry("proto", 0, sleep_dir);
+	if (ent == NULL) {
+		BT_ERR("Unable to create /proc/%s/proto entry", PROC_DIR);
+		retval = -ENOMEM;
+		goto fail;
+	}
+	ent->read_proc = bluesleep_read_proc_proto;
+	ent->write_proc = bluesleep_write_proc_proto;
+
+	/* read only proc entries */
+	if (create_proc_read_entry("asleep", 0,
+			sleep_dir, bluesleep_read_proc_asleep, NULL) == NULL) {
+		BT_ERR("Unable to create /proc/%s/asleep entry", PROC_DIR);
+		retval = -ENOMEM;
+		goto fail;
+	}
+
+	flags = 0; /* clear all status bits */
+
+	/* Initialize spinlock. */
+	spin_lock_init(&rw_lock);
+
+	/* Initialize timer */
+	init_timer(&tx_timer);
+	tx_timer.function = bluesleep_tx_timer_expire;
+	tx_timer.data = 0;
+
+	/* initialize host wake tasklet */
+	tasklet_init(&hostwake_task, bluesleep_hostwake_task, 0);
+
+	/* assert bt wake */
+	if (bsi->has_ext_wake == 1)
+		gpio_set_value(bsi->ext_wake, 1);
+	set_bit(BT_EXT_WAKE, &flags);
+	hci_register_notifier(&hci_event_nblock);
+
+	return 0;
+
+fail:
+	remove_proc_entry("asleep", sleep_dir);
+	remove_proc_entry("proto", sleep_dir);
+	remove_proc_entry("hostwake", sleep_dir);
+	remove_proc_entry("btwake", sleep_dir);
+	remove_proc_entry("sleep", bluetooth_dir);
+	remove_proc_entry("bluetooth", 0);
+	return retval;
+}
+
+/**
+ * Cleans up the module.
+ */
+static void __exit bluesleep_exit(void)
+{
+	/* assert bt wake */
+	if (bsi->has_ext_wake == 1)
+		gpio_set_value(bsi->ext_wake, 1);
+	set_bit(BT_EXT_WAKE, &flags);
+	if (test_bit(BT_PROTO, &flags)) {
+		if (disable_irq_wake(bsi->host_wake_irq))
+			BT_ERR("Couldn't disable hostwake IRQ wakeup mode\n");
+		free_irq(bsi->host_wake_irq, NULL);
+		del_timer(&tx_timer);
+		if (test_bit(BT_ASLEEP, &flags))
+			hsuart_power(1);
+	}
+
+	hci_unregister_notifier(&hci_event_nblock);
+	platform_driver_unregister(&bluesleep_driver);
+
+	remove_proc_entry("asleep", sleep_dir);
+	remove_proc_entry("proto", sleep_dir);
+	remove_proc_entry("hostwake", sleep_dir);
+	remove_proc_entry("btwake", sleep_dir);
+	remove_proc_entry("sleep", bluetooth_dir);
+	remove_proc_entry("bluetooth", 0);
+}
+
+module_init(bluesleep_init);
+module_exit(bluesleep_exit);
+
+MODULE_DESCRIPTION("Bluetooth Sleep Mode Driver ver %s " VERSION);
+#ifdef MODULE_LICENSE
+MODULE_LICENSE("GPL");
+#endif
+