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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2017-11-16 16:09:29 -0800
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2017-11-29 22:52:51 -0800
commit4c83c071b7849ca3e8072284a8587669d8ba6a3d (patch)
tree7a74cd7b32c8da9547b8cbba2ea45356b501dedc /drivers/input
parentda8df83957b179e5edc1029f637e5b69eff44967 (diff)
Input: elants_i2c - do not clobber interrupt trigger on x86
This is similar to commit a4b0a58bb142 ("Input: elan_i2c - do not clobber interrupt trigger on x86") 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. Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input')
-rw-r--r--drivers/input/touchscreen/elants_i2c.c10
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c
index e102d7764bc2..a458e5ec9e41 100644
--- a/drivers/input/touchscreen/elants_i2c.c
+++ b/drivers/input/touchscreen/elants_i2c.c
@@ -27,6 +27,7 @@
#include <linux/module.h>
#include <linux/input.h>
#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/platform_device.h>
#include <linux/async.h>
#include <linux/i2c.h>
@@ -1261,10 +1262,13 @@ static int elants_i2c_probe(struct i2c_client *client,
}
/*
- * 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 = client->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(&client->dev, client->irq,
NULL, elants_i2c_irq,