Re: [PATCH 2/2] hid: input: add HID_QUIRK_REUSE_AXES and fix dragonrise
From: Nikolai Kondrashov
Date: Mon Sep 26 2016 - 05:53:16 EST
Hi Benjamin,
On 09/26/2016 12:29 PM, Benjamin Tissoires wrote:
Ideally, we need to have Dragon Rise 0x0011 tested too. Nick, would you
mind checking it if you still have this particular device?
I never had it, but perhaps Vladislav still has some.
Vladislav, would you be able to test a change to the kernel module for your
Dragonrise gamepads?
Please see below for context.
Thank you.
Nick
On 09/26/2016 12:29 PM, Benjamin Tissoires wrote:
On Sep 26 2016 or thereabouts, Ioan-Adrian Ratiu wrote:
Commit 79346d620e9d ("HID: input: force generic axis to be mapped to their
user space axis") made mapping generic axes to their userspace equivalents
mandatory and some lower end gamepads which were depending on the previous
behaviour suffered severe regressions because they were reusing axes and
expecting hid-input to multiplex their map to the respective userspace axis
by always searching for and using the next available axis.
Yes, I apologies for the breakage and the regression, though I must say
that for now, only one hardware maker and one device (or range of devices
from the look of it) has needed to be quirked.
Now the result is that different device axes appear on a single axis in
userspace, which is clearly a regression in the hid-input driver because it
needs to continue to handle this hardware as expected before the forcing
to provide the same interface to userspace.
Since these lower-end gamepads like 0079:0006 are definitely the exception,
create a quirk to fix them.
Given that we only have this particular vendor that is an issue, I'd
rather see the fix in hid-dr.c. The reason being that you actually don't
need to have a global quirk and this simplifies the path in hid-input.
Plus for users, they can just upgrade hid-dr without having to recompile
their kernel when hid-core is not compiled as a module.
The cleanest solution that wouldn't require any quirk in hid-core is to
simply add an .input_mapping() callback in hid-dr.c.
The code of the callback could be something like (untested):
static int dr_input_mapping(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
switch (usage->hid) {
/*
* revert the old hid-input behavior where axes
* can be randomly assigned when the hid usage is
* reused.
*/
case HID_GD_X: case HID_GD_Y: case HID_GD_Z:
case HID_GD_RX: case HID_GD_RY: case HID_GD_RZ:
if (field->flags & HID_MAIN_ITEM_RELATIVE)
map_rel(usage->hid & 0xf);
else
map_abs(usage->hid & 0xf);
return 1;
}
return 0;
}
Hopefully, something like this should revert the old behavior for all
hid-dr touchpads.
Ideally, we need to have Dragon Rise 0x0011 tested too. Nick, would you
mind checking it if you still have this particular device?
Cheers,
Benjamin
Signed-off-by: Ioan-Adrian Ratiu <adi@xxxxxxxxxx>
---
drivers/hid/hid-dr.c | 2 ++
drivers/hid/hid-input.c | 16 +++++++++++-----
include/linux/hid.h | 1 +
3 files changed, 14 insertions(+), 5 deletions(-)
diff --git a/drivers/hid/hid-dr.c b/drivers/hid/hid-dr.c
index 2523f8a..27fc826 100644
--- a/drivers/hid/hid-dr.c
+++ b/drivers/hid/hid-dr.c
@@ -274,6 +274,8 @@ static int dr_probe(struct hid_device *hdev, const struct hid_device_id *id)
hid_hw_stop(hdev);
goto err;
}
+ /* has only 5 axes and reuses X, Y */
+ hdev->quirks |= HID_QUIRK_REUSE_AXES;
break;
}
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index fb9ace1..1cc6fe4 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -633,11 +633,17 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
/* These usage IDs map directly to the usage codes. */
case HID_GD_X: case HID_GD_Y: case HID_GD_Z:
case HID_GD_RX: case HID_GD_RY: case HID_GD_RZ:
- if (field->flags & HID_MAIN_ITEM_RELATIVE)
- map_rel(usage->hid & 0xf);
- else
- map_abs_clear(usage->hid & 0xf);
- break;
+
+ /* if quirk is active don't force the userspace mapping,
+ * instead search and use the next available axis.
+ */
+ if (!(device->quirks & HID_QUIRK_REUSE_AXES)) {
+ if (field->flags & HID_MAIN_ITEM_RELATIVE)
+ map_rel(usage->hid & 0xf);
+ else
+ map_abs_clear(usage->hid & 0xf);
+ break;
+ }
case HID_GD_SLIDER: case HID_GD_DIAL: case HID_GD_WHEEL:
if (field->flags & HID_MAIN_ITEM_RELATIVE)
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 75b66ec..0979920 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -320,6 +320,7 @@ struct hid_item {
#define HID_QUIRK_NO_EMPTY_INPUT 0x00000100
#define HID_QUIRK_NO_INIT_INPUT_REPORTS 0x00000200
#define HID_QUIRK_ALWAYS_POLL 0x00000400
+#define HID_QUIRK_REUSE_AXES 0x00000800
#define HID_QUIRK_SKIP_OUTPUT_REPORTS 0x00010000
#define HID_QUIRK_SKIP_OUTPUT_REPORT_ID 0x00020000
#define HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP 0x00040000
--
2.10.0