diff mbox

HID: hid-elecom: extend to fix the descriptor for DEFT trackballs.

Message ID 20170421160827.11809-1-flameeyes@flameeyes.eu (mailing list archive)
State Superseded
Headers show

Commit Message

Diego Elio Pettenò April 21, 2017, 4:08 p.m. UTC
The ELECOM DEFT trackballs report only five buttons, when the device
actually has 8. Change the descriptor so that the HID driver can see all of
them.

For completeness and future reference, I included a side-by-side diff of
the part of the descriptor that is being edited.

Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.eu>
---
 drivers/hid/Kconfig      |  6 +++--
 drivers/hid/hid-core.c   |  1 +
 drivers/hid/hid-elecom.c | 57 ++++++++++++++++++++++++++++++++++++++++--------
 drivers/hid/hid-ids.h    |  1 +
 4 files changed, 54 insertions(+), 11 deletions(-)
diff mbox

Patch

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 4070b73..f717b3e 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -258,10 +258,12 @@  config HID_EMS_FF
 	 - Trio Linker Plus II
 
 config HID_ELECOM
-	tristate "ELECOM BM084 bluetooth mouse"
+	tristate "ELECOM HID devices"
 	depends on HID
 	---help---
-	Support for the ELECOM BM084 (bluetooth mouse).
+	Support for ELECOM devices:
+	  - BM084 Bluetooth Mouse
+	  - DEFT Trackball
 
 config HID_ELO
 	tristate "ELO USB 4000/4500 touchscreen"
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index ea36b55..312cf1b 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1891,6 +1891,7 @@  static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY, USB_DEVICE_ID_DREAM_CHEEKY_WN) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY, USB_DEVICE_ID_DREAM_CHEEKY_FA) },
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_DEFT) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0009) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ELO, 0x0030) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_EMS, USB_DEVICE_ID_EMS_TRIO_LINKER_PLUS_II) },
diff --git a/drivers/hid/hid-elecom.c b/drivers/hid/hid-elecom.c
index 6e3848a..4f808c4 100644
--- a/drivers/hid/hid-elecom.c
+++ b/drivers/hid/hid-elecom.c
@@ -1,10 +1,7 @@ 
 /*
- *  HID driver for Elecom BM084 (bluetooth mouse).
- *  Removes a non-existing horizontal wheel from
- *  the HID descriptor.
- *  (This module is based on "hid-ortek".)
- *
+ *  HID driver for ELECOM devices.
  *  Copyright (c) 2010 Richard Nauber <Richard.Nauber@gmail.com>
+ *  Copyright (c) 2017 Diego Elio Pettenò <flameeyes@flameeyes.eu>
  */
 
 /*
@@ -23,15 +20,57 @@ 
 static __u8 *elecom_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) {
-		hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n");
-		rdesc[47] = 0x00;
+	switch (hdev->product) {
+	case USB_DEVICE_ID_ELECOM_BM084:
+		/* The BM084 Bluetooth mouse includes a non-existing horizontal
+		 * wheel in the HID descriptor. */
+		if (*rsize >= 48 && rdesc[46] == 0x05 && rdesc[47] == 0x0c) {
+			hid_info(hdev, "Fixing up Elecom BM084 report descriptor\n");
+			rdesc[47] = 0x00;
+		}
+	case USB_DEVICE_ID_ELECOM_DEFT:
+		/* The DEFT trackball has eight buttons, but its descriptor only
+		 * reports five, disabling the three Fn buttons on the top of
+		 * the mouse.
+		 *
+		 * Apply the following diff to the descriptor:
+		 *
+		 * Collection (Physical),              Collection (Physical),
+		 *     Report ID (1),                      Report ID (1),
+		 *     Report Count (5),            |      Report Count (8),
+		 *     Report Size (1),                    Report Size (1),
+		 *     Usage Page (Button),                Usage Page (Button),
+		 *     Usage Minimum (01h),                Usage Minimum (01h),
+		 *     Usage Maximum (05h),         |      Usage Maximum (08h),
+		 *     Logical Minimum (0),                Logical Minimum (0),
+		 *     Logical Maximum (1),                Logical Maximum (1),
+		 *     Input (Variable),                   Input (Variable),
+		 *     Report Count (1),            |      Report Count (0),
+		 *     Report Size (3),                    Report Size (3),
+		 *     Input (Constant),                   Input (Constant),
+		 *     Report Size (16),                   Report Size (16),
+		 *     Report Count (2),                   Report Count (2),
+		 *     Usage Page (Desktop),               Usage Page (Desktop),
+		 *     Usage (X),                          Usage (X),
+		 *     Usage (Y),                          Usage (Y),
+		 *     Logical Minimum (-32768),           Logical Minimum (-32768),
+		 *     Logical Maximum (32767),            Logical Maximum (32767),
+		 *     Input (Variable, Relative),         Input (Variable, Relative),
+		 * End Collection,                     End Collection,
+		 */
+		if (*rsize == 213 && rdesc[13] == 5 && rdesc[21] == 5) {
+			hid_info(hdev, "Fixing up Elecom DEFT Fn buttons\n");
+			rdesc[13] = 8; /* Button/Variable Report Count */
+			rdesc[21] = 8; /* Button/Variable Usage Maximum */
+			rdesc[29] = 0; /* Button/Constant Report Count */
+		}
 	}
 	return rdesc;
 }
 
 static const struct hid_device_id elecom_devices[] = {
-	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084)},
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_DEFT) },
 	{ }
 };
 MODULE_DEVICE_TABLE(hid, elecom_devices);
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 350accf..69203c9 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -351,6 +351,7 @@ 
 
 #define USB_VENDOR_ID_ELECOM		0x056e
 #define USB_DEVICE_ID_ELECOM_BM084	0x0061
+#define USB_DEVICE_ID_ELECOM_DEFT	0x00ff
 
 #define USB_VENDOR_ID_DREAM_CHEEKY	0x1d34
 #define USB_DEVICE_ID_DREAM_CHEEKY_WN	0x0004