2011-06-01 18:49:35

by Michael Bauer

[permalink] [raw]
Subject: [PATCH v2] hid: Fix Logitech Driving Force Pro wheel

Changes from initial patch:
- shorten comment (removed original descriptor)
- optimized new descriptor (simpler and shorter)

This is a patch for hid-lg.c which fixes the Logitech Driving Force Pro driver.
It was generated against vanilla 2.6.39.
It contains two parts:
- Add the quirk "NOGET" to make the wheel work at all in native mode.
- Replace the somehow broken report descriptor with a custom one to have
separate throttle and brake axes.

As there are significant differences in the descriptor (original descriptor
"hides" the separate axes in a 24 bit FF00 usagepage, new descripter replaces
that with two individual 8 bit desktop.y and desktop.rz usages) I provided a
complete replacement descriptor instead trying to patch the original one.
Patching the descriptor seems not feasible as the new one is much larger.

Note: To actually test this you have to use the tool "ltwheelconf" to put the
DFP into it's native mode - See below for more info.


Background:
Most Logitech wheels are initially reporting themselves with a "fallback"
deviceID (USB_DEVICE_ID_LOGITECH_WHEEL - 0xc294), in order to make sure they
are working even without having the proper driver installed.
If the Logitech driver is installed it sends a special command to the wheel
which sets the wheel to "native mode", enabling enhance features like:
- Clutch pedal
- extended wheel rotation range (up to 900 degrees)
- H-gate shifter
- separate axis for throttle / brake
- all buttons
When the wheel is set to native mode it basically disconnects and reconnects
with a different deviceID (USB_DEVICE_ID_LOGITECH_DFP_WHEEL - 0xc298 in this
case).

I am working on a userspace tool [1] which does the switching from fallback to
native mode. During development I found out that the Driving Force Pro wheel
is not supported in native mode - quierk NOGET is missing and the throttle and
brake axes are reported in a combined way only.


Signed-off-by: Michael Bauer <[email protected]>

[1] https://github.com/TripleSpeeder/LTWheelConf

---

--- 2.6.39_vanilla/drivers/hid/hid-lg.c 2011-05-19 06:06:34.000000000 +0200
+++ 2.6.39/drivers/hid/hid-lg.c 2011-05-30 21:49:51.535184784 +0200
@@ -41,6 +41,66 @@
#define LG_FF3 0x1000
#define LG_FF4 0x2000

+/* Size of the original descriptor of the Driving Force Pro wheel */
+#define DFP_RDESC_ORIG_SIZE 97
+
+/* Fixed report descriptor for Logitech Driving Force Pro wheel controller
+ *
+ * The original descriptor hides the separate throttle and brake axes in
+ * a custom vendor usage page, providing only a combined value as
+ * GenericDesktop.Y.
+ * This descriptor removes the combined Y axis and instead reports
+ * separate throttle (Y) and brake (RZ).
+ */
+static __u8 dfp_rdesc_fixed[] = {
+0x05, 0x01, /* Usage Page (Desktop), */
+0x09, 0x04, /* Usage (Joystik), */
+0xA1, 0x01, /* Collection (Application), */
+0xA1, 0x02, /* Collection (Logical), */
+0x95, 0x01, /* Report Count (1), */
+0x75, 0x0E, /* Report Size (14), */
+0x14, /* Logical Minimum (0), */
+0x26, 0xFF, 0x3F, /* Logical Maximum (16383), */
+0x34, /* Physical Minimum (0), */
+0x46, 0xFF, 0x3F, /* Physical Maximum (16383), */
+0x09, 0x30, /* Usage (X), */
+0x81, 0x02, /* Input (Variable), */
+0x95, 0x0E, /* Report Count (14), */
+0x75, 0x01, /* Report Size (1), */
+0x25, 0x01, /* Logical Maximum (1), */
+0x45, 0x01, /* Physical Maximum (1), */
+0x05, 0x09, /* Usage Page (Button), */
+0x19, 0x01, /* Usage Minimum (01h), */
+0x29, 0x0E, /* Usage Maximum (0Eh), */
+0x81, 0x02, /* Input (Variable), */
+0x05, 0x01, /* Usage Page (Desktop), */
+0x95, 0x01, /* Report Count (1), */
+0x75, 0x04, /* Report Size (4), */
+0x25, 0x07, /* Logical Maximum (7), */
+0x46, 0x3B, 0x01, /* Physical Maximum (315), */
+0x65, 0x14, /* Unit (Degrees), */
+0x09, 0x39, /* Usage (Hat Switch), */
+0x81, 0x42, /* Input (Variable, Nullstate), */
+0x65, 0x00, /* Unit, */
+0x26, 0xFF, 0x00, /* Logical Maximum (255), */
+0x46, 0xFF, 0x00, /* Physical Maximum (255), */
+0x75, 0x08, /* Report Size (8), */
+0x81, 0x01, /* Input (Constant), */
+0x09, 0x31, /* Usage (Y), */
+0x81, 0x02, /* Input (Variable), */
+0x09, 0x35, /* Usage (Rz), */
+0x81, 0x02, /* Input (Variable), */
+0x81, 0x01, /* Input (Constant), */
+0xC0, /* End Collection, */
+0xA1, 0x02, /* Collection (Logical), */
+0x09, 0x02, /* Usage (02h), */
+0x95, 0x07, /* Report Count (7), */
+0x91, 0x02, /* Output (Variable), */
+0xC0, /* End Collection, */
+0xC0 /* End Collection */
+};
+
+
/*
* Certain Logitech keyboards send in report #3 keys which are far
* above the logical maximum described in descriptor. This extends
@@ -74,6 +134,18 @@ static __u8 *lg_report_fixup(struct hid_
rdesc[47] = 0x95;
rdesc[48] = 0x0B;
}
+
+ switch (hdev->product) {
+ case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+ if (*rsize == DFP_RDESC_ORIG_SIZE) {
+ hid_info(hdev,
+ "fixing up Logitech Driving Force Pro report descriptor\n");
+ rdesc = dfp_rdesc_fixed;
+ *rsize = sizeof(dfp_rdesc_fixed);
+ }
+ break;
+ }
+
return rdesc;
}

@@ -378,7 +450,7 @@ static const struct hid_device_id lg_dev
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_G25_WHEEL),
.driver_data = LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_DFP_WHEEL),
- .driver_data = LG_FF },
+ .driver_data = LG_NOGET | LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_WII_WHEEL),
.driver_data = LG_FF4 },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_WINGMAN_FFG ),


2011-06-02 16:35:35

by Simon Wood

[permalink] [raw]
Subject: Re: [PATCH v2] hid: Fix Logitech Driving Force Pro wheel

> Changes from initial patch:
> - shorten comment (removed original descriptor)
> - optimized new descriptor (simpler and shorter)

Concept looks go to me, but I'm getting
--
simon@ubuntu:~/linux-2.6$ patch -p 1 <
../Downloads/v2-hid-Fix-Logitech-Driving-Force-Pro-wheel.patch
patching file drivers/hid/hid-lg.c
patch: **** malformed patch at line 91: USB_DEVICE_ID_LOGITECH_G25_WHEEL), --

Looks like word wrap has been applied to the patch.

It also fails to patch chunk 3 against 3.0rc1 as the G27 wheel has been
added.
--
--- drivers/hid/hid-lg.c 2011-05-19 06:06:34.000000000 +0200
+++ drivers/hid/hid-lg.c 2011-05-30 21:49:51.535184784 +0200
@@ -450,7 +522,7 @@
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_G25_WHEEL),
.driver_data = LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_DFP_WHEEL),
- .driver_data = LG_FF },
+ .driver_data = LG_NOGET | LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,

--
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_G25_WHEEL),
.driver_data = LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_G27_WHEEL),
.driver_data = LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
USB_DEVICE_ID_LOGITECH_DFP_WHEEL),
.driver_data = LG_FF },
--

All that said it appears to build (don't have this wheel to test) and have
it in a git archive if you'd like be to spin a fixed patch for you.

Simon



2011-06-03 15:15:10

by Simon Wood

[permalink] [raw]
Subject: [PATCHv3] hid: Fix Logitech Driving Force Pro wheel

Changes from initial patch:
- shorten comment (removed original descriptor)
- optimized new descriptor (simpler and shorter)
- resent by Simon to fix patch for 3.0rc1

This is a patch for hid-lg.c which fixes the Logitech Driving Force Pro driver.
It was generated against vanilla 2.6.39.
It contains two parts:
- Add the quirk "NOGET" to make the wheel work at all in native mode.
- Replace the somehow broken report descriptor with a custom one to have
separate throttle and brake axes.

As there are significant differences in the descriptor (original descriptor
"hides" the separate axes in a 24 bit FF00 usagepage, new descripter replaces
that with two individual 8 bit desktop.y and desktop.rz usages) I provided a
complete replacement descriptor instead trying to patch the original one.
Patching the descriptor seems not feasible as the new one is much larger.

Note: To actually test this you have to use the tool "ltwheelconf" to put the
DFP into it's native mode - See below for more info.

Background:
Most Logitech wheels are initially reporting themselves with a "fallback"
deviceID (USB_DEVICE_ID_LOGITECH_WHEEL - 0xc294), in order to make sure they
are working even without having the proper driver installed.

If the Logitech driver is installed it sends a special command to the wheel
which sets the wheel to "native mode", enabling enhance features like:
- Clutch pedal
- extended wheel rotation range (up to 900 degrees)
- H-gate shifter
- separate axis for throttle / brake
- all buttons

When the wheel is set to native mode it basically disconnects and reconnects
with a different deviceID (USB_DEVICE_ID_LOGITECH_DFP_WHEEL - 0xc298 in this
case).

I am working on a userspace tool [1] which does the switching from fallback to
native mode. During development I found out that the Driving Force Pro wheel
is not supported in native mode - quierk NOGET is missing and the throttle and
brake axes are reported in a combined way only.

Signed-off-by: Michael Bauer <[email protected]>
Signed-off-by: Simon Wood <[email protected]>

[1] https://github.com/TripleSpeeder/LTWheelConf
---
drivers/hid/hid-lg.c | 74 +++++++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 73 insertions(+), 1 deletions(-)

diff --git a/drivers/hid/hid-lg.c b/drivers/hid/hid-lg.c
index 21f205f..a7f916e 100644
--- a/drivers/hid/hid-lg.c
+++ b/drivers/hid/hid-lg.c
@@ -41,6 +41,66 @@
#define LG_FF3 0x1000
#define LG_FF4 0x2000

+/* Size of the original descriptor of the Driving Force Pro wheel */
+#define DFP_RDESC_ORIG_SIZE 97
+
+/* Fixed report descriptor for Logitech Driving Force Pro wheel controller
+ *
+ * The original descriptor hides the separate throttle and brake axes in
+ * a custom vendor usage page, providing only a combined value as
+ * GenericDesktop.Y.
+ * This descriptor removes the combined Y axis and instead reports
+ * separate throttle (Y) and brake (RZ).
+ */
+static __u8 dfp_rdesc_fixed[] = {
+0x05, 0x01, /* Usage Page (Desktop), */
+0x09, 0x04, /* Usage (Joystik), */
+0xA1, 0x01, /* Collection (Application), */
+0xA1, 0x02, /* Collection (Logical), */
+0x95, 0x01, /* Report Count (1), */
+0x75, 0x0E, /* Report Size (14), */
+0x14, /* Logical Minimum (0), */
+0x26, 0xFF, 0x3F, /* Logical Maximum (16383), */
+0x34, /* Physical Minimum (0), */
+0x46, 0xFF, 0x3F, /* Physical Maximum (16383), */
+0x09, 0x30, /* Usage (X), */
+0x81, 0x02, /* Input (Variable), */
+0x95, 0x0E, /* Report Count (14), */
+0x75, 0x01, /* Report Size (1), */
+0x25, 0x01, /* Logical Maximum (1), */
+0x45, 0x01, /* Physical Maximum (1), */
+0x05, 0x09, /* Usage Page (Button), */
+0x19, 0x01, /* Usage Minimum (01h), */
+0x29, 0x0E, /* Usage Maximum (0Eh), */
+0x81, 0x02, /* Input (Variable), */
+0x05, 0x01, /* Usage Page (Desktop), */
+0x95, 0x01, /* Report Count (1), */
+0x75, 0x04, /* Report Size (4), */
+0x25, 0x07, /* Logical Maximum (7), */
+0x46, 0x3B, 0x01, /* Physical Maximum (315), */
+0x65, 0x14, /* Unit (Degrees), */
+0x09, 0x39, /* Usage (Hat Switch), */
+0x81, 0x42, /* Input (Variable, Nullstate), */
+0x65, 0x00, /* Unit, */
+0x26, 0xFF, 0x00, /* Logical Maximum (255), */
+0x46, 0xFF, 0x00, /* Physical Maximum (255), */
+0x75, 0x08, /* Report Size (8), */
+0x81, 0x01, /* Input (Constant), */
+0x09, 0x31, /* Usage (Y), */
+0x81, 0x02, /* Input (Variable), */
+0x09, 0x35, /* Usage (Rz), */
+0x81, 0x02, /* Input (Variable), */
+0x81, 0x01, /* Input (Constant), */
+0xC0, /* End Collection, */
+0xA1, 0x02, /* Collection (Logical), */
+0x09, 0x02, /* Usage (02h), */
+0x95, 0x07, /* Report Count (7), */
+0x91, 0x02, /* Output (Variable), */
+0xC0, /* End Collection, */
+0xC0 /* End Collection */
+};
+
+
/*
* Certain Logitech keyboards send in report #3 keys which are far
* above the logical maximum described in descriptor. This extends
@@ -74,6 +134,18 @@ static __u8 *lg_report_fixup(struct hid_device *hdev, __u8 *rdesc,
rdesc[47] = 0x95;
rdesc[48] = 0x0B;
}
+
+ switch (hdev->product) {
+ case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
+ if (*rsize == DFP_RDESC_ORIG_SIZE) {
+ hid_info(hdev,
+ "fixing up Logitech Driving Force Pro report descriptor\n");
+ rdesc = dfp_rdesc_fixed;
+ *rsize = sizeof(dfp_rdesc_fixed);
+ }
+ break;
+ }
+
return rdesc;
}

@@ -380,7 +452,7 @@ static const struct hid_device_id lg_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G27_WHEEL),
.driver_data = LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_DFP_WHEEL),
- .driver_data = LG_FF },
+ .driver_data = LG_NOGET | LG_FF },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_WII_WHEEL),
.driver_data = LG_FF4 },
{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_WINGMAN_FFG ),
--
1.7.4.1

2011-06-03 09:25:16

by Michael Bauer

[permalink] [raw]
Subject: Re: [PATCH v2] hid: Fix Logitech Driving Force Pro wheel


>> Changes from initial patch:
>> - shorten comment (removed original descriptor)
>> - optimized new descriptor (simpler and shorter)
>
> Concept looks go to me, but I'm getting
> --
> simon@ubuntu:~/linux-2.6$ patch -p 1 <
> ../Downloads/v2-hid-Fix-Logitech-Driving-Force-Pro-wheel.patch
> patching file drivers/hid/hid-lg.c
> patch: **** malformed patch at line 91: USB_DEVICE_ID_LOGITECH_G25_WHEEL), --
>
> Looks like word wrap has been applied to the patch.
>
> It also fails to patch chunk 3 against 3.0rc1 as the G27 wheel has been
> added.
> [...]

Ouch, seems i messed that up :-/

> All that said it appears to build (don't have this wheel to test) and have
> it in a git archive if you'd like be to spin a fixed patch for you.

Simon, it would be great if you could do this - I am quite busy at work
atm :-( If not let me know, then I'll try to squeeze it in on my side.

Thank you and best regards
Michael



2011-06-07 13:48:50

by Jiri Kosina

[permalink] [raw]
Subject: Re: [PATCHv3] hid: Fix Logitech Driving Force Pro wheel

On Thu, 2 Jun 2011, Simon Wood wrote:

> Changes from initial patch:
> - shorten comment (removed original descriptor)
> - optimized new descriptor (simpler and shorter)
> - resent by Simon to fix patch for 3.0rc1

I have applied the patch (with Michael's authorship metadata). Thanks
guys,

--
Jiri Kosina
SUSE Labs