[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/drivers/acpi/ec.c b/ap/os/linux/linux-3.4.x/drivers/acpi/ec.c
new file mode 100644
index 0000000..d1a9674
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/acpi/ec.c
@@ -0,0 +1,1094 @@
+/*
+ *  ec.c - ACPI Embedded Controller Driver (v2.1)
+ *
+ *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
+ *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
+ *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
+ *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+/* Uncomment next line to get verbose printout */
+/* #define DEBUG */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <asm/io.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+#include <linux/dmi.h>
+
+#include "internal.h"
+
+#define ACPI_EC_CLASS			"embedded_controller"
+#define ACPI_EC_DEVICE_NAME		"Embedded Controller"
+#define ACPI_EC_FILE_INFO		"info"
+
+#undef PREFIX
+#define PREFIX				"ACPI: EC: "
+
+/* EC status register */
+#define ACPI_EC_FLAG_OBF	0x01	/* Output buffer full */
+#define ACPI_EC_FLAG_IBF	0x02	/* Input buffer full */
+#define ACPI_EC_FLAG_BURST	0x10	/* burst mode */
+#define ACPI_EC_FLAG_SCI	0x20	/* EC-SCI occurred */
+
+/* EC commands */
+enum ec_command {
+	ACPI_EC_COMMAND_READ = 0x80,
+	ACPI_EC_COMMAND_WRITE = 0x81,
+	ACPI_EC_BURST_ENABLE = 0x82,
+	ACPI_EC_BURST_DISABLE = 0x83,
+	ACPI_EC_COMMAND_QUERY = 0x84,
+};
+
+#define ACPI_EC_DELAY		500	/* Wait 500ms max. during EC ops */
+#define ACPI_EC_UDELAY_GLK	1000	/* Wait 1ms max. to get global lock */
+#define ACPI_EC_MSI_UDELAY	550	/* Wait 550us for MSI EC */
+
+enum {
+	EC_FLAGS_QUERY_PENDING,		/* Query is pending */
+	EC_FLAGS_GPE_STORM,		/* GPE storm detected */
+	EC_FLAGS_HANDLERS_INSTALLED,	/* Handlers for GPE and
+					 * OpReg are installed */
+	EC_FLAGS_BLOCKED,		/* Transactions are blocked */
+};
+
+/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
+static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
+module_param(ec_delay, uint, 0644);
+MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
+
+/*
+ * If the number of false interrupts per one transaction exceeds
+ * this threshold, will think there is a GPE storm happened and
+ * will disable the GPE for normal transaction.
+ */
+static unsigned int ec_storm_threshold  __read_mostly = 8;
+module_param(ec_storm_threshold, uint, 0644);
+MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
+
+/* If we find an EC via the ECDT, we need to keep a ptr to its context */
+/* External interfaces use first EC only, so remember */
+typedef int (*acpi_ec_query_func) (void *data);
+
+struct acpi_ec_query_handler {
+	struct list_head node;
+	acpi_ec_query_func func;
+	acpi_handle handle;
+	void *data;
+	u8 query_bit;
+};
+
+struct transaction {
+	const u8 *wdata;
+	u8 *rdata;
+	unsigned short irq_count;
+	u8 command;
+	u8 wi;
+	u8 ri;
+	u8 wlen;
+	u8 rlen;
+	bool done;
+};
+
+struct acpi_ec *boot_ec, *first_ec;
+EXPORT_SYMBOL(first_ec);
+
+static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
+static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
+static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
+
+/* --------------------------------------------------------------------------
+                             Transaction Management
+   -------------------------------------------------------------------------- */
+
+static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
+{
+	u8 x = inb(ec->command_addr);
+	pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
+	return x;
+}
+
+static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
+{
+	u8 x = inb(ec->data_addr);
+	pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
+	return x;
+}
+
+static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
+{
+	pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
+	outb(command, ec->command_addr);
+}
+
+static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
+{
+	pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
+	outb(data, ec->data_addr);
+}
+
+static int ec_transaction_done(struct acpi_ec *ec)
+{
+	unsigned long flags;
+	int ret = 0;
+	spin_lock_irqsave(&ec->curr_lock, flags);
+	if (!ec->curr || ec->curr->done)
+		ret = 1;
+	spin_unlock_irqrestore(&ec->curr_lock, flags);
+	return ret;
+}
+
+static void start_transaction(struct acpi_ec *ec)
+{
+	ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
+	ec->curr->done = false;
+	acpi_ec_write_cmd(ec, ec->curr->command);
+}
+
+static void advance_transaction(struct acpi_ec *ec, u8 status)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&ec->curr_lock, flags);
+	if (!ec->curr)
+		goto unlock;
+	if (ec->curr->wlen > ec->curr->wi) {
+		if ((status & ACPI_EC_FLAG_IBF) == 0)
+			acpi_ec_write_data(ec,
+				ec->curr->wdata[ec->curr->wi++]);
+		else
+			goto err;
+	} else if (ec->curr->rlen > ec->curr->ri) {
+		if ((status & ACPI_EC_FLAG_OBF) == 1) {
+			ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
+			if (ec->curr->rlen == ec->curr->ri)
+				ec->curr->done = true;
+		} else
+			goto err;
+	} else if (ec->curr->wlen == ec->curr->wi &&
+		   (status & ACPI_EC_FLAG_IBF) == 0)
+		ec->curr->done = true;
+	goto unlock;
+err:
+	/* false interrupt, state didn't change */
+	if (in_interrupt())
+		++ec->curr->irq_count;
+unlock:
+	spin_unlock_irqrestore(&ec->curr_lock, flags);
+}
+
+static int acpi_ec_sync_query(struct acpi_ec *ec);
+
+static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
+{
+	if (state & ACPI_EC_FLAG_SCI) {
+		if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
+			return acpi_ec_sync_query(ec);
+	}
+	return 0;
+}
+
+static int ec_poll(struct acpi_ec *ec)
+{
+	unsigned long flags;
+	int repeat = 5; /* number of command restarts */
+	while (repeat--) {
+		unsigned long delay = jiffies +
+			msecs_to_jiffies(ec_delay);
+		do {
+			/* don't sleep with disabled interrupts */
+			if (EC_FLAGS_MSI || irqs_disabled()) {
+				udelay(ACPI_EC_MSI_UDELAY);
+				if (ec_transaction_done(ec))
+					return 0;
+			} else {
+				if (wait_event_timeout(ec->wait,
+						ec_transaction_done(ec),
+						msecs_to_jiffies(1)))
+					return 0;
+			}
+			advance_transaction(ec, acpi_ec_read_status(ec));
+		} while (time_before(jiffies, delay));
+		pr_debug(PREFIX "controller reset, restart transaction\n");
+		spin_lock_irqsave(&ec->curr_lock, flags);
+		start_transaction(ec);
+		spin_unlock_irqrestore(&ec->curr_lock, flags);
+	}
+	return -ETIME;
+}
+
+static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
+					struct transaction *t)
+{
+	unsigned long tmp;
+	int ret = 0;
+	if (EC_FLAGS_MSI)
+		udelay(ACPI_EC_MSI_UDELAY);
+	/* start transaction */
+	spin_lock_irqsave(&ec->curr_lock, tmp);
+	/* following two actions should be kept atomic */
+	ec->curr = t;
+	start_transaction(ec);
+	if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
+		clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
+	spin_unlock_irqrestore(&ec->curr_lock, tmp);
+	ret = ec_poll(ec);
+	spin_lock_irqsave(&ec->curr_lock, tmp);
+	ec->curr = NULL;
+	spin_unlock_irqrestore(&ec->curr_lock, tmp);
+	return ret;
+}
+
+static int ec_check_ibf0(struct acpi_ec *ec)
+{
+	u8 status = acpi_ec_read_status(ec);
+	return (status & ACPI_EC_FLAG_IBF) == 0;
+}
+
+static int ec_wait_ibf0(struct acpi_ec *ec)
+{
+	unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
+	/* interrupt wait manually if GPE mode is not active */
+	while (time_before(jiffies, delay))
+		if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
+					msecs_to_jiffies(1)))
+			return 0;
+	return -ETIME;
+}
+
+static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
+{
+	int status;
+	u32 glk;
+	if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
+		return -EINVAL;
+	if (t->rdata)
+		memset(t->rdata, 0, t->rlen);
+	mutex_lock(&ec->lock);
+	if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
+		status = -EINVAL;
+		goto unlock;
+	}
+	if (ec->global_lock) {
+		status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
+		if (ACPI_FAILURE(status)) {
+			status = -ENODEV;
+			goto unlock;
+		}
+	}
+	if (ec_wait_ibf0(ec)) {
+		pr_err(PREFIX "input buffer is not empty, "
+				"aborting transaction\n");
+		status = -ETIME;
+		goto end;
+	}
+	pr_debug(PREFIX "transaction start\n");
+	/* disable GPE during transaction if storm is detected */
+	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
+		/* It has to be disabled, so that it doesn't trigger. */
+		acpi_disable_gpe(NULL, ec->gpe);
+	}
+
+	status = acpi_ec_transaction_unlocked(ec, t);
+
+	/* check if we received SCI during transaction */
+	ec_check_sci_sync(ec, acpi_ec_read_status(ec));
+	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
+		msleep(1);
+		/* It is safe to enable the GPE outside of the transaction. */
+		acpi_enable_gpe(NULL, ec->gpe);
+	} else if (t->irq_count > ec_storm_threshold) {
+		pr_info(PREFIX "GPE storm detected, "
+			"transactions will use polling mode\n");
+		set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
+	}
+	pr_debug(PREFIX "transaction end\n");
+end:
+	if (ec->global_lock)
+		acpi_release_global_lock(glk);
+unlock:
+	mutex_unlock(&ec->lock);
+	return status;
+}
+
+static int acpi_ec_burst_enable(struct acpi_ec *ec)
+{
+	u8 d;
+	struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
+				.wdata = NULL, .rdata = &d,
+				.wlen = 0, .rlen = 1};
+
+	return acpi_ec_transaction(ec, &t);
+}
+
+static int acpi_ec_burst_disable(struct acpi_ec *ec)
+{
+	struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
+				.wdata = NULL, .rdata = NULL,
+				.wlen = 0, .rlen = 0};
+
+	return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
+				acpi_ec_transaction(ec, &t) : 0;
+}
+
+static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
+{
+	int result;
+	u8 d;
+	struct transaction t = {.command = ACPI_EC_COMMAND_READ,
+				.wdata = &address, .rdata = &d,
+				.wlen = 1, .rlen = 1};
+
+	result = acpi_ec_transaction(ec, &t);
+	*data = d;
+	return result;
+}
+
+static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
+{
+	u8 wdata[2] = { address, data };
+	struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
+				.wdata = wdata, .rdata = NULL,
+				.wlen = 2, .rlen = 0};
+
+	return acpi_ec_transaction(ec, &t);
+}
+
+/*
+ * Externally callable EC access functions. For now, assume 1 EC only
+ */
+int ec_burst_enable(void)
+{
+	if (!first_ec)
+		return -ENODEV;
+	return acpi_ec_burst_enable(first_ec);
+}
+
+EXPORT_SYMBOL(ec_burst_enable);
+
+int ec_burst_disable(void)
+{
+	if (!first_ec)
+		return -ENODEV;
+	return acpi_ec_burst_disable(first_ec);
+}
+
+EXPORT_SYMBOL(ec_burst_disable);
+
+int ec_read(u8 addr, u8 * val)
+{
+	int err;
+	u8 temp_data;
+
+	if (!first_ec)
+		return -ENODEV;
+
+	err = acpi_ec_read(first_ec, addr, &temp_data);
+
+	if (!err) {
+		*val = temp_data;
+		return 0;
+	} else
+		return err;
+}
+
+EXPORT_SYMBOL(ec_read);
+
+int ec_write(u8 addr, u8 val)
+{
+	int err;
+
+	if (!first_ec)
+		return -ENODEV;
+
+	err = acpi_ec_write(first_ec, addr, val);
+
+	return err;
+}
+
+EXPORT_SYMBOL(ec_write);
+
+int ec_transaction(u8 command,
+		   const u8 * wdata, unsigned wdata_len,
+		   u8 * rdata, unsigned rdata_len)
+{
+	struct transaction t = {.command = command,
+				.wdata = wdata, .rdata = rdata,
+				.wlen = wdata_len, .rlen = rdata_len};
+	if (!first_ec)
+		return -ENODEV;
+
+	return acpi_ec_transaction(first_ec, &t);
+}
+
+EXPORT_SYMBOL(ec_transaction);
+
+/* Get the handle to the EC device */
+acpi_handle ec_get_handle(void)
+{
+	if (!first_ec)
+		return NULL;
+	return first_ec->handle;
+}
+
+EXPORT_SYMBOL(ec_get_handle);
+
+void acpi_ec_block_transactions(void)
+{
+	struct acpi_ec *ec = first_ec;
+
+	if (!ec)
+		return;
+
+	mutex_lock(&ec->lock);
+	/* Prevent transactions from being carried out */
+	set_bit(EC_FLAGS_BLOCKED, &ec->flags);
+	mutex_unlock(&ec->lock);
+}
+
+void acpi_ec_unblock_transactions(void)
+{
+	struct acpi_ec *ec = first_ec;
+
+	if (!ec)
+		return;
+
+	mutex_lock(&ec->lock);
+	/* Allow transactions to be carried out again */
+	clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
+	mutex_unlock(&ec->lock);
+}
+
+void acpi_ec_unblock_transactions_early(void)
+{
+	/*
+	 * Allow transactions to happen again (this function is called from
+	 * atomic context during wakeup, so we don't need to acquire the mutex).
+	 */
+	if (first_ec)
+		clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
+}
+
+static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
+{
+	int result;
+	u8 d;
+	struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
+				.wdata = NULL, .rdata = &d,
+				.wlen = 0, .rlen = 1};
+	if (!ec || !data)
+		return -EINVAL;
+	/*
+	 * Query the EC to find out which _Qxx method we need to evaluate.
+	 * Note that successful completion of the query causes the ACPI_EC_SCI
+	 * bit to be cleared (and thus clearing the interrupt source).
+	 */
+	result = acpi_ec_transaction_unlocked(ec, &t);
+	if (result)
+		return result;
+	if (!d)
+		return -ENODATA;
+	*data = d;
+	return 0;
+}
+
+/* --------------------------------------------------------------------------
+                                Event Management
+   -------------------------------------------------------------------------- */
+int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
+			      acpi_handle handle, acpi_ec_query_func func,
+			      void *data)
+{
+	struct acpi_ec_query_handler *handler =
+	    kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
+	if (!handler)
+		return -ENOMEM;
+
+	handler->query_bit = query_bit;
+	handler->handle = handle;
+	handler->func = func;
+	handler->data = data;
+	mutex_lock(&ec->lock);
+	list_add(&handler->node, &ec->list);
+	mutex_unlock(&ec->lock);
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
+
+void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
+{
+	struct acpi_ec_query_handler *handler, *tmp;
+	mutex_lock(&ec->lock);
+	list_for_each_entry_safe(handler, tmp, &ec->list, node) {
+		if (query_bit == handler->query_bit) {
+			list_del(&handler->node);
+			kfree(handler);
+		}
+	}
+	mutex_unlock(&ec->lock);
+}
+
+EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
+
+static void acpi_ec_run(void *cxt)
+{
+	struct acpi_ec_query_handler *handler = cxt;
+	if (!handler)
+		return;
+	pr_debug(PREFIX "start query execution\n");
+	if (handler->func)
+		handler->func(handler->data);
+	else if (handler->handle)
+		acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
+	pr_debug(PREFIX "stop query execution\n");
+	kfree(handler);
+}
+
+static int acpi_ec_sync_query(struct acpi_ec *ec)
+{
+	u8 value = 0;
+	int status;
+	struct acpi_ec_query_handler *handler, *copy;
+	if ((status = acpi_ec_query_unlocked(ec, &value)))
+		return status;
+	list_for_each_entry(handler, &ec->list, node) {
+		if (value == handler->query_bit) {
+			/* have custom handler for this bit */
+			copy = kmalloc(sizeof(*handler), GFP_KERNEL);
+			if (!copy)
+				return -ENOMEM;
+			memcpy(copy, handler, sizeof(*copy));
+			pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
+			return acpi_os_execute((copy->func) ?
+				OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
+				acpi_ec_run, copy);
+		}
+	}
+	return 0;
+}
+
+static void acpi_ec_gpe_query(void *ec_cxt)
+{
+	struct acpi_ec *ec = ec_cxt;
+	if (!ec)
+		return;
+	mutex_lock(&ec->lock);
+	acpi_ec_sync_query(ec);
+	mutex_unlock(&ec->lock);
+}
+
+static int ec_check_sci(struct acpi_ec *ec, u8 state)
+{
+	if (state & ACPI_EC_FLAG_SCI) {
+		if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
+			pr_debug(PREFIX "push gpe query to the queue\n");
+			return acpi_os_execute(OSL_NOTIFY_HANDLER,
+				acpi_ec_gpe_query, ec);
+		}
+	}
+	return 0;
+}
+
+static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
+	u32 gpe_number, void *data)
+{
+	struct acpi_ec *ec = data;
+
+	pr_debug(PREFIX "~~~> interrupt\n");
+
+	advance_transaction(ec, acpi_ec_read_status(ec));
+	if (ec_transaction_done(ec) &&
+	    (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
+		wake_up(&ec->wait);
+		ec_check_sci(ec, acpi_ec_read_status(ec));
+	}
+	return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
+}
+
+/* --------------------------------------------------------------------------
+                             Address Space Management
+   -------------------------------------------------------------------------- */
+
+static acpi_status
+acpi_ec_space_handler(u32 function, acpi_physical_address address,
+		      u32 bits, u64 *value64,
+		      void *handler_context, void *region_context)
+{
+	struct acpi_ec *ec = handler_context;
+	int result = 0, i, bytes = bits / 8;
+	u8 *value = (u8 *)value64;
+
+	if ((address > 0xFF) || !value || !handler_context)
+		return AE_BAD_PARAMETER;
+
+	if (function != ACPI_READ && function != ACPI_WRITE)
+		return AE_BAD_PARAMETER;
+
+	if (EC_FLAGS_MSI || bits > 8)
+		acpi_ec_burst_enable(ec);
+
+	for (i = 0; i < bytes; ++i, ++address, ++value)
+		result = (function == ACPI_READ) ?
+			acpi_ec_read(ec, address, value) :
+			acpi_ec_write(ec, address, *value);
+
+	if (EC_FLAGS_MSI || bits > 8)
+		acpi_ec_burst_disable(ec);
+
+	switch (result) {
+	case -EINVAL:
+		return AE_BAD_PARAMETER;
+		break;
+	case -ENODEV:
+		return AE_NOT_FOUND;
+		break;
+	case -ETIME:
+		return AE_TIME;
+		break;
+	default:
+		return AE_OK;
+	}
+}
+
+/* --------------------------------------------------------------------------
+                               Driver Interface
+   -------------------------------------------------------------------------- */
+static acpi_status
+ec_parse_io_ports(struct acpi_resource *resource, void *context);
+
+static struct acpi_ec *make_acpi_ec(void)
+{
+	struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
+	if (!ec)
+		return NULL;
+	ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
+	mutex_init(&ec->lock);
+	init_waitqueue_head(&ec->wait);
+	INIT_LIST_HEAD(&ec->list);
+	spin_lock_init(&ec->curr_lock);
+	return ec;
+}
+
+static acpi_status
+acpi_ec_register_query_methods(acpi_handle handle, u32 level,
+			       void *context, void **return_value)
+{
+	char node_name[5];
+	struct acpi_buffer buffer = { sizeof(node_name), node_name };
+	struct acpi_ec *ec = context;
+	int value = 0;
+	acpi_status status;
+
+	status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
+
+	if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
+		acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
+	}
+	return AE_OK;
+}
+
+static acpi_status
+ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
+{
+	acpi_status status;
+	unsigned long long tmp = 0;
+
+	struct acpi_ec *ec = context;
+
+	/* clear addr values, ec_parse_io_ports depend on it */
+	ec->command_addr = ec->data_addr = 0;
+
+	status = acpi_walk_resources(handle, METHOD_NAME__CRS,
+				     ec_parse_io_ports, ec);
+	if (ACPI_FAILURE(status))
+		return status;
+
+	/* Get GPE bit assignment (EC events). */
+	/* TODO: Add support for _GPE returning a package */
+	status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
+	if (ACPI_FAILURE(status))
+		return status;
+	ec->gpe = tmp;
+	/* Use the global lock for all EC transactions? */
+	tmp = 0;
+	acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
+	ec->global_lock = tmp;
+	ec->handle = handle;
+	return AE_CTRL_TERMINATE;
+}
+
+static int ec_install_handlers(struct acpi_ec *ec)
+{
+	acpi_status status;
+	if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
+		return 0;
+	status = acpi_install_gpe_handler(NULL, ec->gpe,
+				  ACPI_GPE_EDGE_TRIGGERED,
+				  &acpi_ec_gpe_handler, ec);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	acpi_enable_gpe(NULL, ec->gpe);
+	status = acpi_install_address_space_handler(ec->handle,
+						    ACPI_ADR_SPACE_EC,
+						    &acpi_ec_space_handler,
+						    NULL, ec);
+	if (ACPI_FAILURE(status)) {
+		if (status == AE_NOT_FOUND) {
+			/*
+			 * Maybe OS fails in evaluating the _REG object.
+			 * The AE_NOT_FOUND error will be ignored and OS
+			 * continue to initialize EC.
+			 */
+			printk(KERN_ERR "Fail in evaluating the _REG object"
+				" of EC device. Broken bios is suspected.\n");
+		} else {
+			acpi_remove_gpe_handler(NULL, ec->gpe,
+				&acpi_ec_gpe_handler);
+			acpi_disable_gpe(NULL, ec->gpe);
+			return -ENODEV;
+		}
+	}
+
+	set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
+	return 0;
+}
+
+static void ec_remove_handlers(struct acpi_ec *ec)
+{
+	acpi_disable_gpe(NULL, ec->gpe);
+	if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
+				ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
+		pr_err(PREFIX "failed to remove space handler\n");
+	if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
+				&acpi_ec_gpe_handler)))
+		pr_err(PREFIX "failed to remove gpe handler\n");
+	clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
+}
+
+static int acpi_ec_add(struct acpi_device *device)
+{
+	struct acpi_ec *ec = NULL;
+	int ret;
+
+	strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
+	strcpy(acpi_device_class(device), ACPI_EC_CLASS);
+
+	/* Check for boot EC */
+	if (boot_ec &&
+	    (boot_ec->handle == device->handle ||
+	     boot_ec->handle == ACPI_ROOT_OBJECT)) {
+		ec = boot_ec;
+		boot_ec = NULL;
+	} else {
+		ec = make_acpi_ec();
+		if (!ec)
+			return -ENOMEM;
+	}
+	if (ec_parse_device(device->handle, 0, ec, NULL) !=
+		AE_CTRL_TERMINATE) {
+			kfree(ec);
+			return -EINVAL;
+	}
+
+	/* Find and register all query methods */
+	acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
+			    acpi_ec_register_query_methods, NULL, ec, NULL);
+
+	if (!first_ec)
+		first_ec = ec;
+	device->driver_data = ec;
+
+	ret = !!request_region(ec->data_addr, 1, "EC data");
+	WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
+	ret = !!request_region(ec->command_addr, 1, "EC cmd");
+	WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
+
+	pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
+			  ec->gpe, ec->command_addr, ec->data_addr);
+
+	ret = ec_install_handlers(ec);
+
+	/* EC is fully operational, allow queries */
+	clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
+	return ret;
+}
+
+static int acpi_ec_remove(struct acpi_device *device, int type)
+{
+	struct acpi_ec *ec;
+	struct acpi_ec_query_handler *handler, *tmp;
+
+	if (!device)
+		return -EINVAL;
+
+	ec = acpi_driver_data(device);
+	ec_remove_handlers(ec);
+	mutex_lock(&ec->lock);
+	list_for_each_entry_safe(handler, tmp, &ec->list, node) {
+		list_del(&handler->node);
+		kfree(handler);
+	}
+	mutex_unlock(&ec->lock);
+	release_region(ec->data_addr, 1);
+	release_region(ec->command_addr, 1);
+	device->driver_data = NULL;
+	if (ec == first_ec)
+		first_ec = NULL;
+	kfree(ec);
+	return 0;
+}
+
+static acpi_status
+ec_parse_io_ports(struct acpi_resource *resource, void *context)
+{
+	struct acpi_ec *ec = context;
+
+	if (resource->type != ACPI_RESOURCE_TYPE_IO)
+		return AE_OK;
+
+	/*
+	 * The first address region returned is the data port, and
+	 * the second address region returned is the status/command
+	 * port.
+	 */
+	if (ec->data_addr == 0)
+		ec->data_addr = resource->data.io.minimum;
+	else if (ec->command_addr == 0)
+		ec->command_addr = resource->data.io.minimum;
+	else
+		return AE_CTRL_TERMINATE;
+
+	return AE_OK;
+}
+
+int __init acpi_boot_ec_enable(void)
+{
+	if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
+		return 0;
+	if (!ec_install_handlers(boot_ec)) {
+		first_ec = boot_ec;
+		return 0;
+	}
+	return -EFAULT;
+}
+
+static const struct acpi_device_id ec_device_ids[] = {
+	{"PNP0C09", 0},
+	{"", 0},
+};
+
+/* Some BIOS do not survive early DSDT scan, skip it */
+static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
+{
+	EC_FLAGS_SKIP_DSDT_SCAN = 1;
+	return 0;
+}
+
+/* ASUStek often supplies us with broken ECDT, validate it */
+static int ec_validate_ecdt(const struct dmi_system_id *id)
+{
+	EC_FLAGS_VALIDATE_ECDT = 1;
+	return 0;
+}
+
+/* MSI EC needs special treatment, enable it */
+static int ec_flag_msi(const struct dmi_system_id *id)
+{
+	printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
+	EC_FLAGS_MSI = 1;
+	EC_FLAGS_VALIDATE_ECDT = 1;
+	return 0;
+}
+
+/*
+ * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
+ * the GPE storm threshold back to 20
+ */
+static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
+{
+	pr_debug("Setting the EC GPE storm threshold to 20\n");
+	ec_storm_threshold  = 20;
+	return 0;
+}
+
+static struct dmi_system_id __initdata ec_dmi_table[] = {
+	{
+	ec_skip_dsdt_scan, "Compal JFL92", {
+	DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
+	DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
+	{
+	ec_flag_msi, "MSI hardware", {
+	DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
+	{
+	ec_flag_msi, "MSI hardware", {
+	DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
+	{
+	ec_flag_msi, "MSI hardware", {
+	DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
+	{
+	ec_flag_msi, "MSI hardware", {
+	DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
+	{
+	ec_flag_msi, "Quanta hardware", {
+	DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
+	DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
+	{
+	ec_flag_msi, "Quanta hardware", {
+	DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
+	DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
+	{
+	ec_validate_ecdt, "ASUS hardware", {
+	DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
+	{
+	ec_validate_ecdt, "ASUS hardware", {
+	DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
+	{
+	ec_enlarge_storm_threshold, "CLEVO hardware", {
+	DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
+	DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
+	{
+	ec_skip_dsdt_scan, "HP Folio 13", {
+	DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+	DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL},
+	{
+	ec_validate_ecdt, "ASUS hardware", {
+	DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
+	DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
+	{},
+};
+
+int __init acpi_ec_ecdt_probe(void)
+{
+	acpi_status status;
+	struct acpi_ec *saved_ec = NULL;
+	struct acpi_table_ecdt *ecdt_ptr;
+
+	boot_ec = make_acpi_ec();
+	if (!boot_ec)
+		return -ENOMEM;
+	/*
+	 * Generate a boot ec context
+	 */
+	dmi_check_system(ec_dmi_table);
+	status = acpi_get_table(ACPI_SIG_ECDT, 1,
+				(struct acpi_table_header **)&ecdt_ptr);
+	if (ACPI_SUCCESS(status)) {
+		pr_info(PREFIX "EC description table is found, configuring boot EC\n");
+		boot_ec->command_addr = ecdt_ptr->control.address;
+		boot_ec->data_addr = ecdt_ptr->data.address;
+		boot_ec->gpe = ecdt_ptr->gpe;
+		boot_ec->handle = ACPI_ROOT_OBJECT;
+		acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
+		/* Don't trust ECDT, which comes from ASUSTek */
+		if (!EC_FLAGS_VALIDATE_ECDT)
+			goto install;
+		saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
+		if (!saved_ec)
+			return -ENOMEM;
+	/* fall through */
+	}
+
+	if (EC_FLAGS_SKIP_DSDT_SCAN)
+		return -ENODEV;
+
+	/* This workaround is needed only on some broken machines,
+	 * which require early EC, but fail to provide ECDT */
+	printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
+	status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
+					boot_ec, NULL);
+	/* Check that acpi_get_devices actually find something */
+	if (ACPI_FAILURE(status) || !boot_ec->handle)
+		goto error;
+	if (saved_ec) {
+		/* try to find good ECDT from ASUSTek */
+		if (saved_ec->command_addr != boot_ec->command_addr ||
+		    saved_ec->data_addr != boot_ec->data_addr ||
+		    saved_ec->gpe != boot_ec->gpe ||
+		    saved_ec->handle != boot_ec->handle)
+			pr_info(PREFIX "ASUSTek keeps feeding us with broken "
+			"ECDT tables, which are very hard to workaround. "
+			"Trying to use DSDT EC info instead. Please send "
+			"output of acpidump to linux-acpi@vger.kernel.org\n");
+		kfree(saved_ec);
+		saved_ec = NULL;
+	} else {
+		/* We really need to limit this workaround, the only ASUS,
+		* which needs it, has fake EC._INI method, so use it as flag.
+		* Keep boot_ec struct as it will be needed soon.
+		*/
+		acpi_handle dummy;
+		if (!dmi_name_in_vendors("ASUS") ||
+		    ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
+							&dummy)))
+			return -ENODEV;
+	}
+install:
+	if (!ec_install_handlers(boot_ec)) {
+		first_ec = boot_ec;
+		return 0;
+	}
+error:
+	kfree(boot_ec);
+	boot_ec = NULL;
+	return -ENODEV;
+}
+
+static struct acpi_driver acpi_ec_driver = {
+	.name = "ec",
+	.class = ACPI_EC_CLASS,
+	.ids = ec_device_ids,
+	.ops = {
+		.add = acpi_ec_add,
+		.remove = acpi_ec_remove,
+		},
+};
+
+int __init acpi_ec_init(void)
+{
+	int result = 0;
+
+	/* Now register the driver for the EC */
+	result = acpi_bus_register_driver(&acpi_ec_driver);
+	if (result < 0)
+		return -ENODEV;
+
+	return result;
+}
+
+/* EC driver currently not unloadable */
+#if 0
+static void __exit acpi_ec_exit(void)
+{
+
+	acpi_bus_unregister_driver(&acpi_ec_driver);
+	return;
+}
+#endif	/* 0 */