Commit 451566f4 authored by Dmitry Torokhov's avatar Dmitry Torokhov Committed by Len Brown
Browse files

[ACPI] Enable EC Burst Mode 

Fixes several Embedded Controller issues, including
button failure and battery status AE_TIME failure.

http://bugzilla.kernel.org/show_bug.cgi?id=3851



Based on patch by: Andi Kleen <ak@suse.de>
Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
Signed-off-by: default avatarLuming Yu <luming.yu@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent b913100d

drivers/acpi/ec.c

+276 −114
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ 
#include <linux/delay.h>

#include <linux/proc_fs.h>

#include <linux/seq_file.h>

#include <linux/interrupt.h>

#include <asm/io.h>

#include <acpi/acpi_bus.h>

#include <acpi/acpi_drivers.h>
@@ -49,17 +50,19 @@ ACPI_MODULE_NAME ("acpi_ec") 


#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 */



#define ACPI_EC_EVENT_OBF	0x01	/* Output buffer full */

#define ACPI_EC_EVENT_IBE	0x02	/* Input buffer empty */



#define ACPI_EC_UDELAY		100	/* Poll @ 100us increments */

#define ACPI_EC_UDELAY_COUNT	1000	/* Wait 10ms max. during EC ops */

#define ACPI_EC_DELAY		50	/* Wait 50ms max. during EC ops */

#define ACPI_EC_UDELAY_GLK	1000	/* Wait 1ms max. to get global lock */



#define ACPI_EC_COMMAND_READ	0x80

#define ACPI_EC_COMMAND_WRITE	0x81

#define ACPI_EC_BURST_ENABLE	0x82

#define ACPI_EC_BURST_DISABLE	0x83

#define ACPI_EC_COMMAND_QUERY	0x84



static int acpi_ec_add (struct acpi_device *device);
@@ -87,7 +90,11 @@ struct acpi_ec { 
	struct acpi_generic_address	command_addr;

	struct acpi_generic_address	data_addr;

	unsigned long			global_lock;

	spinlock_t			lock;

	unsigned int			expect_event;

	atomic_t			leaving_burst; /* 0 : No, 1 : Yes, 2: abort*/

	atomic_t			pending_gpe;

	struct semaphore		sem;

	wait_queue_head_t		wait;

};



/* If we find an EC via the ECDT, we need to keep a ptr to its context */
@@ -100,59 +107,138 @@ static struct acpi_device *first_ec; 
                             Transaction Management

   -------------------------------------------------------------------------- */



static int

acpi_ec_wait (

	struct acpi_ec		*ec,

	u8			event)

static inline u32 acpi_ec_read_status(struct acpi_ec *ec)

{

	u32			acpi_ec_status = 0;

	u32			i = ACPI_EC_UDELAY_COUNT;

	u32	status = 0;



	if (!ec)

		return -EINVAL;

	acpi_hw_low_level_read(8, &status, &ec->status_addr);

	return status;

}



static int acpi_ec_wait(struct acpi_ec *ec, unsigned int event)

{

	int	result = 0;



	ACPI_FUNCTION_TRACE("acpi_ec_wait");



	/* Poll the EC status register waiting for the event to occur. */

	ec->expect_event = event;

	smp_mb();



	result = wait_event_interruptible_timeout(ec->wait,

					!ec->expect_event,

					msecs_to_jiffies(ACPI_EC_DELAY));

	

	ec->expect_event = 0;

	smp_mb();



	if (result < 0){

		ACPI_DEBUG_PRINT((ACPI_DB_ERROR," result  = %d ", result));

		return_VALUE(result);

	}



	/*

	 * Verify that the event in question has actually happened by

	 * querying EC status. Do the check even if operation timed-out

	 * to make sure that we did not miss interrupt.

	 */

	switch (event) {

	case ACPI_EC_EVENT_OBF:

		do {

			acpi_hw_low_level_read(8, &acpi_ec_status, &ec->status_addr);

			if (acpi_ec_status & ACPI_EC_FLAG_OBF)

				return 0;

			udelay(ACPI_EC_UDELAY);

		} while (--i>0);

		if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)

			return_VALUE(0);

		break;



	case ACPI_EC_EVENT_IBE:

		do {

			acpi_hw_low_level_read(8, &acpi_ec_status, &ec->status_addr);

			if (!(acpi_ec_status & ACPI_EC_FLAG_IBF))

				return 0;

			udelay(ACPI_EC_UDELAY);

		} while (--i>0);

		if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)

			return_VALUE(0);

		break;

	default:

		return -EINVAL;

	}



	return -ETIME;

	return_VALUE(-ETIME);

}







static int

acpi_ec_enter_burst_mode (

	struct acpi_ec		*ec)

{

	u32			tmp = 0;

	int			status = 0;



	ACPI_FUNCTION_TRACE("acpi_ec_enter_burst_mode");



	status = acpi_ec_read_status(ec);

	if (status != -EINVAL &&

		!(status & ACPI_EC_FLAG_BURST)){

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"entering burst mode \n"));

		acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE, &ec->command_addr);

		status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);

		if (status){

			acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

			ACPI_DEBUG_PRINT((ACPI_DB_ERROR," status = %d\n", status));

			return_VALUE(-EINVAL);

		}

		acpi_hw_low_level_read(8, &tmp, &ec->data_addr);

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		if(tmp != 0x90 ) {/* Burst ACK byte*/

			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,"Ack failed \n"));

			return_VALUE(-EINVAL);

		}

	} else

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"already be in burst mode \n"));

	atomic_set(&ec->leaving_burst , 0);

	return_VALUE(0);

}



static int

acpi_ec_leave_burst_mode (

	struct acpi_ec		*ec)

{

	int			status =0;



	ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");



	atomic_set(&ec->leaving_burst , 1);

	status = acpi_ec_read_status(ec);

	if (status != -EINVAL &&

		(status & ACPI_EC_FLAG_BURST)){

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"leaving burst mode\n"));

		acpi_hw_low_level_write(8, ACPI_EC_BURST_DISABLE, &ec->command_addr);

		status = acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);

		if (status){

			acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,"------->wait fail\n"));

			return_VALUE(-EINVAL);

		}

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		status = acpi_ec_read_status(ec);

		if (status != -EINVAL &&

			(status & ACPI_EC_FLAG_BURST)) {

			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,"------->status fail\n"));

			return_VALUE(-EINVAL);

		}

	}else

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"already be in Non-burst mode \n"));

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,"leaving burst mode\n"));



	return_VALUE(0);

}



static int

acpi_ec_read (

	struct acpi_ec		*ec,

	u8			address,

	u32			*data)

{

	acpi_status		status = AE_OK;

	int			result = 0;

	unsigned long		flags = 0;

	u32			glk = 0;

	int			status = 0;

	u32			glk;



	ACPI_FUNCTION_TRACE("acpi_ec_read");



	if (!ec || !data)

		return_VALUE(-EINVAL);



retry:

	*data = 0;



	if (ec->global_lock) {
@@ -161,31 +247,49 @@ acpi_ec_read ( 
			return_VALUE(-ENODEV);

	}



	spin_lock_irqsave(&ec->lock, flags);

	WARN_ON(in_interrupt());

	down(&ec->sem);



	if(acpi_ec_enter_burst_mode(ec))

		goto end;



	acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ, &ec->command_addr);

	result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	if (result)

	status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

	if (status) {

		goto end;

	}



	acpi_hw_low_level_write(8, address, &ec->data_addr);

	result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);

	if (result)

	status= acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);

	if (status){

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		goto end;



	}



	acpi_hw_low_level_read(8, data, &ec->data_addr);

	acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);



	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",

		*data, address));

	

end:

	spin_unlock_irqrestore(&ec->lock, flags);

	acpi_ec_leave_burst_mode(ec);

	up(&ec->sem);



	if (ec->global_lock)

		acpi_release_global_lock(glk);



	return_VALUE(result);

	if(atomic_read(&ec->leaving_burst) == 2){

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));

		while(!atomic_read(&ec->pending_gpe)){

			msleep(1);	

		}

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		goto retry;

	}



	return_VALUE(status);

}
@@ -195,49 +299,80 @@ acpi_ec_write ( 
	u8			address,

	u8			data)

{

	int			result = 0;

	acpi_status		status = AE_OK;

	unsigned long		flags = 0;

	u32			glk = 0;

	int			status = 0;

	u32			glk;

	u32			tmp;



	ACPI_FUNCTION_TRACE("acpi_ec_write");



	if (!ec)

		return_VALUE(-EINVAL);



retry:

	if (ec->global_lock) {

		status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);

		if (ACPI_FAILURE(status))

			return_VALUE(-ENODEV);

	}



	spin_lock_irqsave(&ec->lock, flags);

	WARN_ON(in_interrupt());

	down(&ec->sem);



	if(acpi_ec_enter_burst_mode(ec))

		goto end;



	status = acpi_ec_read_status(ec);

	if (status != -EINVAL &&

		!(status & ACPI_EC_FLAG_BURST)){

		acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE, &ec->command_addr);

		status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);

		if (status)

			goto end;

		acpi_hw_low_level_read(8, &tmp, &ec->data_addr);

		if(tmp != 0x90 ) /* Burst ACK byte*/

			goto end;

	}

	/*Now we are in burst mode*/



	acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE, &ec->command_addr);

	result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	if (result)

	status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

	if (status){

		goto end;

	}



	acpi_hw_low_level_write(8, address, &ec->data_addr);

	result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	if (result)

	status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	if (status){

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		goto end;

	}



	acpi_hw_low_level_write(8, data, &ec->data_addr);

	result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	if (result)

	status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);

	acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

	if (status)

		goto end;



	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",

		data, address));



end:

	spin_unlock_irqrestore(&ec->lock, flags);

	acpi_ec_leave_burst_mode(ec);

	up(&ec->sem);



	if (ec->global_lock)

		acpi_release_global_lock(glk);



	return_VALUE(result);

	if(atomic_read(&ec->leaving_burst) == 2){

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));

		while(!atomic_read(&ec->pending_gpe)){

			msleep(1);	

		}

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		goto retry;

	}



	return_VALUE(status);

}



/*
@@ -289,16 +424,14 @@ acpi_ec_query ( 
	struct acpi_ec		*ec,

	u32			*data)

{

	int			result = 0;

	acpi_status		status = AE_OK;

	unsigned long		flags = 0;

	u32			glk = 0;

	int			status = 0;

	u32			glk;



	ACPI_FUNCTION_TRACE("acpi_ec_query");



	if (!ec || !data)

		return_VALUE(-EINVAL);



retry:

	*data = 0;



	if (ec->global_lock) {
@@ -307,29 +440,43 @@ acpi_ec_query ( 
			return_VALUE(-ENODEV);

	}



	down(&ec->sem);

	if(acpi_ec_enter_burst_mode(ec))

		goto end;

	/*

	 * 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).

	 */

	spin_lock_irqsave(&ec->lock, flags);



	acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY, &ec->command_addr);

	result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);

	if (result)

	status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);

	if (status){

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		goto end;

	}



	acpi_hw_low_level_read(8, data, &ec->data_addr);

	acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

	if (!*data)

		result = -ENODATA;

		status = -ENODATA;



end:

	spin_unlock_irqrestore(&ec->lock, flags);

	acpi_ec_leave_burst_mode(ec);

	up(&ec->sem);



	if (ec->global_lock)

		acpi_release_global_lock(glk);



	return_VALUE(result);

	if(atomic_read(&ec->leaving_burst) == 2){

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,"aborted, retry ...\n"));

		while(!atomic_read(&ec->pending_gpe)){

			msleep(1);	

		}

		acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

		goto retry;

	}



	return_VALUE(status);

}
@@ -347,31 +494,18 @@ acpi_ec_gpe_query ( 
	void			*ec_cxt)

{

	struct acpi_ec		*ec = (struct acpi_ec *) ec_cxt;

	u32			value = 0;

	unsigned long		flags = 0;

	u32			value;

	int			result = -ENODATA;

	static char		object_name[5] = {'_','Q','0','0','\0'};

	const char		hex[] = {'0','1','2','3','4','5','6','7',

				         '8','9','A','B','C','D','E','F'};



	ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");



	if (!ec_cxt)

		goto end;	



	spin_lock_irqsave(&ec->lock, flags);

	acpi_hw_low_level_read(8, &value, &ec->command_addr);

	spin_unlock_irqrestore(&ec->lock, flags);

	if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)

		result = acpi_ec_query(ec, &value);



	/* TBD: Implement asynch events!

	 * NOTE: All we care about are EC-SCI's.  Other EC events are

	 * handled via polling (yuck!).  This is because some systems

	 * treat EC-SCIs as level (versus EDGE!) triggered, preventing

	 *  a purely interrupt-driven approach (grumble, grumble).

	 */

	if (!(value & ACPI_EC_FLAG_SCI))

		goto end;



	if (acpi_ec_query(ec, &value))

	if (result)

		goto end;



	object_name[2] = hex[((value >> 4) & 0x0F)];
@@ -380,9 +514,9 @@ acpi_ec_gpe_query ( 
	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));



	acpi_evaluate_object(ec->handle, object_name, NULL, NULL);



	atomic_dec(&ec->pending_gpe);

end:	

	acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);

	return;

}



static u32
@@ -390,6 +524,7 @@ acpi_ec_gpe_handler ( 
	void			*data)

{

	acpi_status		status = AE_OK;

	u32			value;

	struct acpi_ec		*ec = (struct acpi_ec *) data;



	if (!ec)
@@ -397,13 +532,39 @@ acpi_ec_gpe_handler ( 


	acpi_disable_gpe(NULL, ec->gpe_bit, ACPI_ISR);



	value = acpi_ec_read_status(ec);



	if((value & ACPI_EC_FLAG_IBF) &&

		!(value & ACPI_EC_FLAG_BURST) &&

			(atomic_read(&ec->leaving_burst) == 0)) { 

	/*

	 * the embedded controller disables 

	 * burst mode for any reason other 

	 * than the burst disable command

	 * to process critical event.

	 */

		atomic_set(&ec->leaving_burst , 2); /* block current pending transaction

					and retry */

		wake_up(&ec->wait);

	}else {

		if ((ec->expect_event == ACPI_EC_EVENT_OBF &&

				(value & ACPI_EC_FLAG_OBF)) ||

	    			(ec->expect_event == ACPI_EC_EVENT_IBE &&

				!(value & ACPI_EC_FLAG_IBF))) {

			ec->expect_event = 0;

			wake_up(&ec->wait);

			

		}

	}



	if (value & ACPI_EC_FLAG_SCI){

		atomic_add(1, &ec->pending_gpe) ;

		status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,

						acpi_ec_gpe_query, ec);

	} 



	if (status == AE_OK)

		return ACPI_INTERRUPT_HANDLED;

	else

		return ACPI_INTERRUPT_NOT_HANDLED;

	return status == AE_OK ?

		ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;

}



/* --------------------------------------------------------------------------
@@ -421,10 +582,8 @@ acpi_ec_space_setup ( 
	 * The EC object is in the handler context and is needed

	 * when calling the acpi_ec_space_handler.

	 */

	if(function == ACPI_REGION_DEACTIVATE) 

		*return_context = NULL;

	else 

		*return_context = handler_context;

	*return_context  = (function != ACPI_REGION_DEACTIVATE) ?

						handler_context : NULL;



	return AE_OK;

}
@@ -555,7 +714,7 @@ static int 
acpi_ec_add_fs (

	struct acpi_device	*device)

{

	struct proc_dir_entry	*entry = NULL;

	struct proc_dir_entry	*entry;



	ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
@@ -606,9 +765,9 @@ static int 
acpi_ec_add (

	struct acpi_device	*device)

{

	int			result = 0;

	acpi_status		status = AE_OK;

	struct acpi_ec		*ec = NULL;

	int			result;

	acpi_status		status;

	struct acpi_ec		*ec;

	unsigned long		uid;



	ACPI_FUNCTION_TRACE("acpi_ec_add");
@@ -623,7 +782,10 @@ acpi_ec_add ( 


	ec->handle = device->handle;

	ec->uid = -1;

	spin_lock_init(&ec->lock);

 	atomic_set(&ec->pending_gpe, 0);

 	atomic_set(&ec->leaving_burst , 1);

 	init_MUTEX(&ec->sem);

 	init_waitqueue_head(&ec->wait);

	strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);

	strcpy(acpi_device_class(device), ACPI_EC_CLASS);

	acpi_driver_data(device) = ec;
@@ -677,7 +839,7 @@ acpi_ec_remove ( 
	struct acpi_device	*device,

	int			type)

{

	struct acpi_ec		*ec = NULL;

	struct acpi_ec		*ec;



	ACPI_FUNCTION_TRACE("acpi_ec_remove");
@@ -732,8 +894,8 @@ static int 
acpi_ec_start (

	struct acpi_device	*device)

{

	acpi_status		status = AE_OK;

	struct acpi_ec		*ec = NULL;

	acpi_status		status;

	struct acpi_ec		*ec;



	ACPI_FUNCTION_TRACE("acpi_ec_start");
@@ -789,8 +951,8 @@ acpi_ec_stop ( 
	struct acpi_device	*device,

	int			type)

{

	acpi_status		status = AE_OK;

	struct acpi_ec		*ec = NULL;

	acpi_status		status;

	struct acpi_ec		*ec;



	ACPI_FUNCTION_TRACE("acpi_ec_stop");
@@ -832,7 +994,6 @@ acpi_fake_ecdt_callback ( 
	status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec_ecdt->gpe_bit);

	if (ACPI_FAILURE(status))

		return status;

	spin_lock_init(&ec_ecdt->lock);

	ec_ecdt->global_lock = TRUE;

	ec_ecdt->handle = handle;
@@ -905,11 +1066,12 @@ acpi_ec_get_real_ecdt(void) 
		return -ENOMEM;

	memset(ec_ecdt, 0, sizeof(struct acpi_ec));



 	init_MUTEX(&ec_ecdt->sem);

 	init_waitqueue_head(&ec_ecdt->wait);

	ec_ecdt->command_addr = ecdt_ptr->ec_control;

	ec_ecdt->status_addr = ecdt_ptr->ec_control;

	ec_ecdt->data_addr = ecdt_ptr->ec_data;

	ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;

	spin_lock_init(&ec_ecdt->lock);

	/* use the GL just to be safe */

	ec_ecdt->global_lock = TRUE;

	ec_ecdt->uid = ecdt_ptr->uid;
@@ -978,7 +1140,7 @@ error: 


static int __init acpi_ec_init (void)

{

	int			result = 0;

	int			result;



	ACPI_FUNCTION_TRACE("acpi_ec_init");

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