1 files changed, 46 insertions, 94 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 391f331674c..839b542d508 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -68,15 +68,13 @@ enum ec_command {
 #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_CDELAY		10	/* Wait 10us before polling EC */
+#define ACPI_EC_MSI_UDELAY	550	/* Wait 550us for MSI EC */
 
 #define ACPI_EC_STORM_THRESHOLD 8	/* number of false interrupts
 					   per one transaction */
 
 enum {
 	EC_FLAGS_QUERY_PENDING,		/* Query is pending */
-	EC_FLAGS_GPE_MODE,		/* Expect GPE to be sent
-					 * for status change */
-	EC_FLAGS_NO_GPE,		/* Don't use GPE mode */
 	EC_FLAGS_GPE_STORM,		/* GPE storm detected */
 	EC_FLAGS_HANDLERS_INSTALLED	/* Handlers for GPE and
 					 * OpReg are installed */
@@ -170,7 +168,7 @@ static void start_transaction(struct acpi_ec *ec)
 	acpi_ec_write_cmd(ec, ec->curr->command);
 }
 
-static void gpe_transaction(struct acpi_ec *ec, u8 status)
+static void advance_transaction(struct acpi_ec *ec, u8 status)
 {
 	unsigned long flags;
 	spin_lock_irqsave(&ec->curr_lock, flags);
@@ -201,29 +199,6 @@ unlock:
 	spin_unlock_irqrestore(&ec->curr_lock, flags);
 }
 
-static int acpi_ec_wait(struct acpi_ec *ec)
-{
-	if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
-			       msecs_to_jiffies(ACPI_EC_DELAY)))
-		return 0;
-	/* try restart command if we get any false interrupts */
-	if (ec->curr->irq_count &&
-	    (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
-		pr_debug(PREFIX "controller reset, restart transaction\n");
-		start_transaction(ec);
-		if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
-					msecs_to_jiffies(ACPI_EC_DELAY)))
-			return 0;
-	}
-	/* missing GPEs, switch back to poll mode */
-	if (printk_ratelimit())
-		pr_info(PREFIX "missing confirmations, "
-				"switch off interrupt mode.\n");
-	set_bit(EC_FLAGS_NO_GPE, &ec->flags);
-	clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
-	return 1;
-}
-
 static void acpi_ec_gpe_query(void *ec_cxt);
 
 static int ec_check_sci(struct acpi_ec *ec, u8 state)
@@ -236,43 +211,51 @@ static int ec_check_sci(struct acpi_ec *ec, u8 state)
 	return 0;
 }
 
-static void ec_delay(void)
-{
-	/* EC in MSI notebooks don't tolerate delays other than 550 usec */
-	if (EC_FLAGS_MSI)
-		udelay(ACPI_EC_DELAY);
-	else
-		/* Use shortest sleep available */
-		msleep(1);
-}
-
 static int ec_poll(struct acpi_ec *ec)
 {
-	unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
-	udelay(ACPI_EC_CDELAY);
-	while (time_before(jiffies, delay)) {
-		gpe_transaction(ec, acpi_ec_read_status(ec));
-		ec_delay();
-		if (ec_transaction_done(ec))
-			return 0;
+	unsigned long flags;
+	int repeat = 2; /* number of command restarts */
+	while (repeat--) {
+		unsigned long delay = jiffies +
+			msecs_to_jiffies(ACPI_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));
+		if (!ec->curr->irq_count ||
+		    (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
+			break;
+		/* try restart command if we get any false interrupts */
+		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,
-					int force_poll)
+					struct transaction *t)
 {
 	unsigned long tmp;
 	int ret = 0;
 	pr_debug(PREFIX "transaction start\n");
 	/* disable GPE during transaction if storm is detected */
 	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
-		clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 		acpi_disable_gpe(NULL, ec->gpe);
 	}
 	if (EC_FLAGS_MSI)
-		udelay(ACPI_EC_DELAY);
+		udelay(ACPI_EC_MSI_UDELAY);
 	/* start transaction */
 	spin_lock_irqsave(&ec->curr_lock, tmp);
 	/* following two actions should be kept atomic */
@@ -281,11 +264,7 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 	if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 		clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 	spin_unlock_irqrestore(&ec->curr_lock, tmp);
-	/* if we selected poll mode or failed in GPE-mode do a poll loop */
-	if (force_poll ||
-	    !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
-	    acpi_ec_wait(ec))
-		ret = ec_poll(ec);
+	ret = ec_poll(ec);
 	pr_debug(PREFIX "transaction end\n");
 	spin_lock_irqsave(&ec->curr_lock, tmp);
 	ec->curr = NULL;
@@ -295,8 +274,7 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 		ec_check_sci(ec, acpi_ec_read_status(ec));
 		/* it is safe to enable GPE outside of transaction */
 		acpi_enable_gpe(NULL, ec->gpe);
-	} else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
-		   t->irq_count > ACPI_EC_STORM_THRESHOLD) {
+	} else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 		pr_info(PREFIX "GPE storm detected, "
 			"transactions will use polling mode\n");
 		set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
@@ -314,16 +292,14 @@ static int ec_wait_ibf0(struct acpi_ec *ec)
 {
 	unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 	/* interrupt wait manually if GPE mode is not active */
-	unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
-		msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
 	while (time_before(jiffies, delay))
-		if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
+		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 force_poll)
+static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 {
 	int status;
 	u32 glk;
@@ -345,7 +321,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 		status = -ETIME;
 		goto end;
 	}
-	status = acpi_ec_transaction_unlocked(ec, t, force_poll);
+	status = acpi_ec_transaction_unlocked(ec, t);
 end:
 	if (ec->global_lock)
 		acpi_release_global_lock(glk);
@@ -365,7 +341,7 @@ static int acpi_ec_burst_enable(struct acpi_ec *ec)
 				.wdata = NULL, .rdata = &d,
 				.wlen = 0, .rlen = 1};
 
-	return acpi_ec_transaction(ec, &t, 0);
+	return acpi_ec_transaction(ec, &t);
 }
 
 static int acpi_ec_burst_disable(struct acpi_ec *ec)
@@ -375,7 +351,7 @@ static int acpi_ec_burst_disable(struct acpi_ec *ec)
 				.wlen = 0, .rlen = 0};
 
 	return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
-				acpi_ec_transaction(ec, &t, 0) : 0;
+				acpi_ec_transaction(ec, &t) : 0;
 }
 
 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
@@ -386,7 +362,7 @@ static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 				.wdata = &address, .rdata = &d,
 				.wlen = 1, .rlen = 1};
 
-	result = acpi_ec_transaction(ec, &t, 0);
+	result = acpi_ec_transaction(ec, &t);
 	*data = d;
 	return result;
 }
@@ -398,7 +374,7 @@ static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 				.wdata = wdata, .rdata = NULL,
 				.wlen = 2, .rlen = 0};
 
-	return acpi_ec_transaction(ec, &t, 0);
+	return acpi_ec_transaction(ec, &t);
 }
 
 /*
@@ -466,7 +442,7 @@ int ec_transaction(u8 command,
 	if (!first_ec)
 		return -ENODEV;
 
-	return acpi_ec_transaction(first_ec, &t, force_poll);
+	return acpi_ec_transaction(first_ec, &t);
 }
 
 EXPORT_SYMBOL(ec_transaction);
@@ -487,7 +463,7 @@ static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 	 * bit to be cleared (and thus clearing the interrupt source).
 	 */
 
-	result = acpi_ec_transaction(ec, &t, 0);
+	result = acpi_ec_transaction(ec, &t);
 	if (result)
 		return result;
 
@@ -570,28 +546,10 @@ static u32 acpi_ec_gpe_handler(void *data)
 	pr_debug(PREFIX "~~~> interrupt\n");
 	status = acpi_ec_read_status(ec);
 
-	if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
-		gpe_transaction(ec, status);
-		if (ec_transaction_done(ec) &&
-		    (status & ACPI_EC_FLAG_IBF) == 0)
-			wake_up(&ec->wait);
-	}
-
+	advance_transaction(ec, status);
+	if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
+		wake_up(&ec->wait);
 	ec_check_sci(ec, status);
-	if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
-	    !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
-		/* this is non-query, must be confirmation */
-		if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
-			if (printk_ratelimit())
-				pr_info(PREFIX "non-query interrupt received,"
-					" switching to interrupt mode\n");
-		} else {
-			/* hush, STORM switches the mode every transaction */
-			pr_debug(PREFIX "non-query interrupt received,"
-				" switching to interrupt mode\n");
-		}
-		set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
-	}
 	return ACPI_INTERRUPT_HANDLED;
 }
 
@@ -837,8 +795,6 @@ static int acpi_ec_add(struct acpi_device *device)
 	acpi_ec_add_fs(device);
 	pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 			  ec->gpe, ec->command_addr, ec->data_addr);
-	pr_info(PREFIX "driver started in %s mode\n",
-		(test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 	return 0;
 }
 
@@ -1054,8 +1010,6 @@ static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 {
 	struct acpi_ec *ec = acpi_driver_data(device);
 	/* Stop using GPE */
-	set_bit(EC_FLAGS_NO_GPE, &ec->flags);
-	clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 	acpi_disable_gpe(NULL, ec->gpe);
 	return 0;
 }
@@ -1064,8 +1018,6 @@ static int acpi_ec_resume(struct acpi_device *device)
 {
 	struct acpi_ec *ec = acpi_driver_data(device);
 	/* Enable use of GPE back */
-	clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
-	set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 	acpi_enable_gpe(NULL, ec->gpe);
 	return 0;
 }