On x86 we historically used falling edge interrupts in the driver because that's how first Chrome devices were configured. They also did not use ACPI to enumerate I2C devices (because back then there was no kernel support for that), so trigger was hard-coded in the driver. However the controller behavior is much more reliable if we use level triggers, and that is how we configured ARM devices, and how want to configure newer x86 devices as well. All newer x86 boxes have their I2C devices enumerated in ACPI. Let's see if platform code (ACPI, DT) described interrupt and specified particular trigger type, and if so, let's use it instead of always clobbering trigger with IRQF_TRIGGER_FALLING. We will still use this trigger type as a fallback if platform code left interrupt trigger unconfigured. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196761 Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> --- drivers/input/mouse/elan_i2c_core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/input/mouse/elan_i2c_core.c b/drivers/input/mouse/elan_i2c_core.c index a2d2077303cb..c33f2cce6ba9 100644 --- a/drivers/input/mouse/elan_i2c_core.c +++ b/drivers/input/mouse/elan_i2c_core.c @@ -26,6 +26,7 @@ #include <linux/init.h> #include <linux/input/mt.h> #include <linux/interrupt.h> +#include <linux/irq.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/kernel.h> @@ -1141,10 +1142,13 @@ static int elan_probe(struct i2c_client *client, return error; /* - * Systems using device tree should set up interrupt via DTS, - * the rest will use the default falling edge interrupts. + * Platform code (ACPI, DTS) should normally set up interrupt + * for us, but in case it did not let's fall back to using falling + * edge to be compatible with older Chromebooks. */ - irqflags = dev->of_node ? 0 : IRQF_TRIGGER_FALLING; + irqflags = irq_get_trigger_type(client->irq); + if (!irqflags) + irqflags = IRQF_TRIGGER_FALLING; error = devm_request_threaded_irq(dev, client->irq, NULL, elan_isr, irqflags | IRQF_ONESHOT, -- 2.14.2.822.g60be5d43e6-goog -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
