Commit ca8283dc authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

ACPI: EC: Call advance_transaction() from acpi_ec_dispatch_gpe() 



Calling acpi_dispatch_gpe() from acpi_ec_dispatch_gpe() is generally
problematic, because it may cause the spurious interrupt handling in
advance_transaction() to trigger in theory.

However, instead of calling acpi_dispatch_gpe() to dispatch the EC
GPE, acpi_ec_dispatch_gpe() can call advance_transaction() directly
on first_ec and it can pass 'false' as its second argument to indicate
calling it from process context.

Moreover, if advance_transaction() is modified to return a bool value
indicating whether or not the EC work needs to be flushed, it can be
used to avoid unnecessary EC work flushing in acpi_ec_dispatch_gpe(),
so change the code accordingly.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 4a9af6ca

drivers/acpi/ec.c

+28 −11
Original line number Original line Diff line number Diff line
@@ -170,7 +170,7 @@ struct acpi_ec_query { 
};

};





static int acpi_ec_query(struct acpi_ec *ec, u8 *data);

static int acpi_ec_query(struct acpi_ec *ec, u8 *data);

static void advance_transaction(struct acpi_ec *ec, bool interrupt);

static bool advance_transaction(struct acpi_ec *ec, bool interrupt);

static void acpi_ec_event_handler(struct work_struct *work);

static void acpi_ec_event_handler(struct work_struct *work);

static void acpi_ec_event_processor(struct work_struct *work);

static void acpi_ec_event_processor(struct work_struct *work);
@@ -444,18 +444,25 @@ static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 
	return true;

	return true;

}

}





static void acpi_ec_submit_query(struct acpi_ec *ec)

static bool acpi_ec_submit_query(struct acpi_ec *ec)

{

{

	acpi_ec_mask_events(ec);

	acpi_ec_mask_events(ec);

	if (!acpi_ec_event_enabled(ec))

	if (!acpi_ec_event_enabled(ec))

		return;

		return false;



	if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {

	if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {

		ec_dbg_evt("Command(%s) submitted/blocked",

		ec_dbg_evt("Command(%s) submitted/blocked",

			   acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));

			   acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));

		ec->nr_pending_queries++;

		ec->nr_pending_queries++;

		ec->events_in_progress++;

		ec->events_in_progress++;

		queue_work(ec_wq, &ec->work);

		return queue_work(ec_wq, &ec->work);

	}

	}



	/*

	 * The event handling work has not been completed yet, so it needs to be

	 * flushed.

	 */

	return true;

}

}





static void acpi_ec_complete_query(struct acpi_ec *ec)

static void acpi_ec_complete_query(struct acpi_ec *ec)
@@ -628,10 +635,11 @@ static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t 
		acpi_ec_mask_events(ec);

		acpi_ec_mask_events(ec);

}

}





static void advance_transaction(struct acpi_ec *ec, bool interrupt)

static bool advance_transaction(struct acpi_ec *ec, bool interrupt)

{

{

	struct transaction *t = ec->curr;

	struct transaction *t = ec->curr;

	bool wakeup = false;

	bool wakeup = false;

	bool ret = false;

	u8 status;

	u8 status;





	ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id());

	ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id());
@@ -698,10 +706,12 @@ static void advance_transaction(struct acpi_ec *ec, bool interrupt) 




out:

out:

	if (status & ACPI_EC_FLAG_SCI)

	if (status & ACPI_EC_FLAG_SCI)

		acpi_ec_submit_query(ec);

		ret = acpi_ec_submit_query(ec);





	if (wakeup && interrupt)

	if (wakeup && interrupt)

		wake_up(&ec->wait);

		wake_up(&ec->wait);



	return ret;

}

}





static void start_transaction(struct acpi_ec *ec)

static void start_transaction(struct acpi_ec *ec)
@@ -2038,8 +2048,7 @@ void acpi_ec_set_gpe_wake_mask(u8 action) 




bool acpi_ec_dispatch_gpe(void)

bool acpi_ec_dispatch_gpe(void)

{

{

	bool work_in_progress;

	bool work_in_progress = false;

	u32 ret;





	if (!first_ec)

	if (!first_ec)

		return acpi_any_gpe_status_set(U32_MAX);

		return acpi_any_gpe_status_set(U32_MAX);
@@ -2055,8 +2064,16 @@ bool acpi_ec_dispatch_gpe(void) 
	 * Dispatch the EC GPE in-band, but do not report wakeup in any case

	 * Dispatch the EC GPE in-band, but do not report wakeup in any case

	 * to allow the caller to process events properly after that.

	 * to allow the caller to process events properly after that.

	 */

	 */

	ret = acpi_dispatch_gpe(NULL, first_ec->gpe);

	spin_lock_irq(&first_ec->lock);

	if (ret == ACPI_INTERRUPT_HANDLED)



	if (acpi_ec_gpe_status_set(first_ec))

		work_in_progress = advance_transaction(first_ec, false);



	spin_unlock_irq(&first_ec->lock);



	if (!work_in_progress)

		return false;



	pm_pr_dbg("ACPI EC GPE dispatched\n");

	pm_pr_dbg("ACPI EC GPE dispatched\n");





	/* Drain EC work. */

	/* Drain EC work. */