On Thu, Sep 28, 2017 at 11:09 AM, Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: > 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 Reviewed-by: Aaron Durbin <adurbin@xxxxxxxxxxxx> -- 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
