linux-kernel - [PATCH v2 5/8] ACPI: PM: s2idle: Switch EC over to polling during "noirq" suspend

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Date:   Tue, 30 Jul 2019 12:00:43 +0200
From:   "Rafael J. Wysocki" <rjw@...ysocki.net>
To:     Linux ACPI <linux-acpi@...r.kernel.org>
Cc:     Linux PM <linux-pm@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Zhang Rui <rui.zhang@...el.com>,
        Rajneesh Bhardwaj <rajneesh.bhardwaj@...ux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Subject: [PATCH v2 5/8] ACPI: PM: s2idle: Switch EC over to polling during "noirq" suspend

From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>

Since the ACPI SCI is set up for system wakeup before the "noirq"
suspend of devices, it is better to make suspend-to-idle follow
suspend-to-RAM (S3) and switch over the EC to polling during "noirq"
suspend (and back to interrupt-based flow during "noirq" resume).

The frequency of spurious wakeup interrupts from the EC may be
reduced this way.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---

New in v2.

---
 drivers/acpi/ec.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Index: linux-pm/drivers/acpi/ec.c
===================================================================
--- linux-pm.orig/drivers/acpi/ec.c
+++ linux-pm/drivers/acpi/ec.c
@@ -1958,8 +1958,7 @@ static int acpi_ec_suspend_noirq(struct
 	    ec->reference_count >= 1)
 		acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
 
-	if (acpi_sleep_no_ec_events())
-		acpi_ec_enter_noirq(ec);
+	acpi_ec_enter_noirq(ec);
 
 	return 0;
 }
@@ -1968,8 +1967,7 @@ static int acpi_ec_resume_noirq(struct d
 {
 	struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
 
-	if (acpi_sleep_no_ec_events())
-		acpi_ec_leave_noirq(ec);
+	acpi_ec_leave_noirq(ec);
 
 	if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
 	    ec->reference_count >= 1)