From: Marc Zyngier <marc.zyngier@arm.com>
Date: Wed, 7 Sep 2016 08:12:11 +0000 (+0100)
Subject: gpio/gpiolib: Forbid irqchip default trigger if probed over DT
X-Git-Tag: v4.9-rc1~122^2~45
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=332e99d5ae4056523bcb24ab16cd7a41474c4807;p=karo-tx-linux.git

gpio/gpiolib: Forbid irqchip default trigger if probed over DT

Using a default trigger is a bad idea if using DT to configure
interrupts, as the device's interrupt specifier will always contain
the trigger configuration.

Let's warn about that particular situation, and revert to not
having a default. Hopefully, the couple of drivers still using
this feature will quickly be fixed.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index deaf4d4dc68e..e183ee2f5f65 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1613,6 +1613,15 @@ int _gpiochip_irqchip_add(struct gpio_chip *gpiochip,
 	if (gpiochip->of_node)
 		of_node = gpiochip->of_node;
 #endif
+	/*
+	 * Specifying a default trigger is a terrible idea if DT is
+	 * used to configure the interrupts, as you may end-up with
+	 * conflicting triggers. Tell the user, and reset to NONE.
+	 */
+	if (WARN(of_node && type != IRQ_TYPE_NONE,
+		 "%s: Ignoring %d default trigger\n", of_node->full_name, type))
+		type = IRQ_TYPE_NONE;
+
 	gpiochip->irqchip = irqchip;
 	gpiochip->irq_handler = handler;
 	gpiochip->irq_default_type = type;