[PATCH v2] Skip deferred request irqs for devices known to fail

From: Ian W MORRISON <ianwmorrison@gmail.com>
To: benjamin.tissoires@redhat.com, hdegoede@redhat.com,
	mika.westerberg@linux.intel.com,
	andriy.shevchenko@linux.intel.com, linus.walleij@linaro.org,
	bgolaszewski@baylibre.com
Cc: linux-gpio@vger.kernel.org, linux-acpi@vger.kernel.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	Ian W MORRISON <ianwmorrison@gmail.com>
Subject: [PATCH v2] Skip deferred request irqs for devices known to fail
Date: Mon, 19 Aug 2019 21:26:37 +1000	[thread overview]
Message-ID: <20190819112637.29943-1-ianwmorrison@gmail.com> (raw)

Patch ca876c7483b6 "gpiolib-acpi: make sure we trigger edge events at
least once on boot" causes the MINIX family of mini PCs to fail to boot
resulting in a "black screen". 

This patch excludes MINIX devices from executing this trigger in order
to successfully boot.

Cc: stable@vger.kernel.org
Signed-off-by: Ian W MORRISON <ianwmorrison@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/gpio/gpiolib-acpi.c | 33 +++++++++++++++++++++++++++------
 1 file changed, 27 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index fdee8afa5339..f6c3dcdc91c9 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -13,6 +13,7 @@
 #include <linux/gpio/machine.h>
 #include <linux/export.h>
 #include <linux/acpi.h>
+#include <linux/dmi.h>
 #include <linux/interrupt.h>
 #include <linux/mutex.h>
 #include <linux/pinctrl/pinctrl.h>
@@ -20,6 +21,17 @@
 #include "gpiolib.h"
 #include "gpiolib-acpi.h"
 
+static const struct dmi_system_id skip_deferred_request_irqs_table[] = {
+	{
+		.ident = "MINIX Z83-4",
+		.matches = {
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "MINIX"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
+		},
+	},
+	{}
+};
+
 /**
  * struct acpi_gpio_event - ACPI GPIO event handler data
  *
@@ -1273,19 +1285,28 @@ bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
 	return con_id == NULL;
 }
 
-/* Run deferred acpi_gpiochip_request_irqs() */
+/*
+ * Run deferred acpi_gpiochip_request_irqs()
+ * but exclude devices known to fail
+*/
 static int acpi_gpio_handle_deferred_request_irqs(void)
 {
 	struct acpi_gpio_chip *acpi_gpio, *tmp;
+	const struct dmi_system_id *dmi_id;
 
-	mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
-	list_for_each_entry_safe(acpi_gpio, tmp,
+	dmi_id = dmi_first_match(skip_deferred_request_irqs_table);
+	if (dmi_id)
+		return 0;
+	else {
+		mutex_lock(&acpi_gpio_deferred_req_irqs_lock);
+		list_for_each_entry_safe(acpi_gpio, tmp,
 				 &acpi_gpio_deferred_req_irqs_list,
 				 deferred_req_irqs_list_entry)
-		acpi_gpiochip_request_irqs(acpi_gpio);
+			acpi_gpiochip_request_irqs(acpi_gpio);
 
-	acpi_gpio_deferred_req_irqs_done = true;
-	mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
+		acpi_gpio_deferred_req_irqs_done = true;
+		mutex_unlock(&acpi_gpio_deferred_req_irqs_lock);
+	}
 
 	return 0;
 }
-- 
2.17.1

