HID: quirk for Saitek RAT7 and MMO7 mices' mode button

Some saitek mice implement a tristate button (for switching button mappings in
the original driver) by keeping one of three (non-physical)
buttons constantly pressed.

This breaks X and probably other userspace software.

This patch implements a quirk for the R.A.T.7 and M.M.O.7, tracking the mode
and generating presses of a single button if it changes.  Also the missing
release event is generated instantly.

Signed-off-by: Harald Brinkmann <hbrinkmann@braincalibration.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

4 files changed, 157 insertions, 8 deletions

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 7af9d0b5dea1..00e01383bf30 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -608,7 +608,10 @@ config HID_SAITEK
         Support for Saitek devices that are not fully compliant with the
         HID standard.
 
-        Currently only supports the PS1000 controller.
+        Supported devices:
+        - PS1000 Dual Analog Pad
+        - R.A.T.7 Gaming Mouse
+        - M.M.O.7 Gaming Mouse
 
 config HID_SAMSUNG
         tristate "Samsung InfraRed remote control or keyboards"
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 10a2c0866459..3d9c6f8efc2a 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1867,7 +1867,11 @@ static const struct hid_device_id hid_have_special_driver[] = {
         { HID_USB_DEVICE(USB_VENDOR_ID_ROCCAT, USB_DEVICE_ID_ROCCAT_RYOS_MK_PRO) },
         { HID_USB_DEVICE(USB_VENDOR_ID_ROCCAT, USB_DEVICE_ID_ROCCAT_SAVU) },
 #endif
+#if IS_ENABLED(CONFIG_HID_SAITEK)
         { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_PS1000) },
+        { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_RAT7) },
+        { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_MMO7) },
+#endif
         { HID_USB_DEVICE(USB_VENDOR_ID_SAMSUNG, USB_DEVICE_ID_SAMSUNG_IR_REMOTE) },
         { HID_USB_DEVICE(USB_VENDOR_ID_SAMSUNG, USB_DEVICE_ID_SAMSUNG_WIRELESS_KBD_MOUSE) },
         { HID_USB_DEVICE(USB_VENDOR_ID_SKYCABLE, USB_DEVICE_ID_SKYCABLE_WIRELESS_PRESENTER) },
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index c8af7202c28d..91db867d89fa 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -761,6 +761,8 @@
 #define USB_VENDOR_ID_SAITEK            0x06a3
 #define USB_DEVICE_ID_SAITEK_RUMBLEPAD  0xff17
 #define USB_DEVICE_ID_SAITEK_PS1000     0x0621
+#define USB_DEVICE_ID_SAITEK_RAT7       0x0cd7
+#define USB_DEVICE_ID_SAITEK_MMO7       0x0cd0
 
 #define USB_VENDOR_ID_SAMSUNG           0x0419
 #define USB_DEVICE_ID_SAMSUNG_IR_REMOTE 0x0001
diff --git a/drivers/hid/hid-saitek.c b/drivers/hid/hid-saitek.c
index 37961c7e397d..69cca1476a0c 100644
--- a/drivers/hid/hid-saitek.c
+++ b/drivers/hid/hid-saitek.c
@@ -1,10 +1,17 @@
 /*
- *  HID driver for Saitek devices, currently only the PS1000 (USB gamepad).
+ *  HID driver for Saitek devices.
+ *
+ *  PS1000 (USB gamepad):
  *  Fixes the HID report descriptor by removing a non-existent axis and
  *  clearing the constant bit on the input reports for buttons and d-pad.
  *  (This module is based on "hid-ortek".)
- *
  *  Copyright (c) 2012 Andreas Hübner
+ *
+ *  R.A.T.7, M.M.O.7 (USB gaming mice):
+ *  Fixes the mode button which cycles through three constantly pressed
+ *  buttons. All three press events are mapped to one button and the
+ *  missing release event is generated immediately.
+ *
  */
 
 /*
@@ -21,12 +28,57 @@
 
 #include "hid-ids.h"
 
+#define SAITEK_FIX_PS1000       0x0001
+#define SAITEK_RELEASE_MODE_RAT7        0x0002
+#define SAITEK_RELEASE_MODE_MMO7        0x0004
+
+struct saitek_sc {
+        unsigned long quirks;
+        int mode;
+};
+
+static int saitek_probe(struct hid_device *hdev,
+                const struct hid_device_id *id)
+{
+        unsigned long quirks = id->driver_data;
+        struct saitek_sc *ssc;
+        int ret;
+
+        ssc = devm_kzalloc(&hdev->dev, sizeof(*ssc), GFP_KERNEL);
+        if (ssc == NULL) {
+                hid_err(hdev, "can't alloc saitek descriptor\n");
+                return -ENOMEM;
+        }
+
+        ssc->quirks = quirks;
+        ssc->mode = -1;
+
+        hid_set_drvdata(hdev, ssc);
+
+        ret = hid_parse(hdev);
+        if (ret) {
+                hid_err(hdev, "parse failed\n");
+                return ret;
+        }
+
+        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+        if (ret) {
+                hid_err(hdev, "hw start failed\n");
+                return ret;
+        }
+
+        return 0;
+}
+
 static __u8 *saitek_report_fixup(struct hid_device *hdev, __u8 *rdesc,
                 unsigned int *rsize)
 {
-        if (*rsize == 137 && rdesc[20] == 0x09 && rdesc[21] == 0x33
-                        && rdesc[94] == 0x81 && rdesc[95] == 0x03
-                        && rdesc[110] == 0x81 && rdesc[111] == 0x03) {
+        struct saitek_sc *ssc = hid_get_drvdata(hdev);
+
+        if ((ssc->quirks & SAITEK_FIX_PS1000) && *rsize == 137 &&
+                        rdesc[20] == 0x09 && rdesc[21] == 0x33 &&
+                        rdesc[94] == 0x81 && rdesc[95] == 0x03 &&
+                        rdesc[110] == 0x81 && rdesc[111] == 0x03) {
 
                 hid_info(hdev, "Fixing up Saitek PS1000 report descriptor\n");
 
@@ -42,8 +94,93 @@ static __u8 *saitek_report_fixup(struct hid_device *hdev, __u8 *rdesc,
         return rdesc;
 }
 
+static int saitek_raw_event(struct hid_device *hdev,
+                struct hid_report *report, u8 *raw_data, int size)
+{
+        struct saitek_sc *ssc = hid_get_drvdata(hdev);
+
+        if (ssc->quirks & SAITEK_RELEASE_MODE_RAT7 && size == 7) {
+                /* R.A.T.7 uses bits 13, 14, 15 for the mode */
+                int mode = -1;
+                if (raw_data[1] & 0x01)
+                        mode = 0;
+                else if (raw_data[1] & 0x02)
+                        mode = 1;
+                else if (raw_data[1] & 0x04)
+                        mode = 2;
+
+                /* clear mode bits */
+                raw_data[1] &= ~0x07;
+
+                if (mode != ssc->mode) {
+                        hid_dbg(hdev, "entered mode %d\n", mode);
+                        if (ssc->mode != -1) {
+                                /* use bit 13 as the mode button */
+                                raw_data[1] |= 0x04;
+                        }
+                        ssc->mode = mode;
+                }
+        } else if (ssc->quirks & SAITEK_RELEASE_MODE_MMO7 && size == 8) {
+
+                /* M.M.O.7 uses bits 8, 22, 23 for the mode */
+                int mode = -1;
+                if (raw_data[1] & 0x80)
+                        mode = 0;
+                else if (raw_data[2] & 0x01)
+                        mode = 1;
+                else if (raw_data[2] & 0x02)
+                        mode = 2;
+
+                /* clear mode bits */
+                raw_data[1] &= ~0x80;
+                raw_data[2] &= ~0x03;
+
+                if (mode != ssc->mode) {
+                        hid_dbg(hdev, "entered mode %d\n", mode);
+                        if (ssc->mode != -1) {
+                                /* use bit 8 as the mode button, bits 22
+                                 * and 23 do not represent buttons
+                                 * according to the HID report descriptor
+                                 */
+                                raw_data[1] |= 0x80;
+                        }
+                        ssc->mode = mode;
+                }
+        }
+
+        return 0;
+}
+
+static int saitek_event(struct hid_device *hdev, struct hid_field *field,
+                struct hid_usage *usage, __s32 value)
+{
+        struct saitek_sc *ssc = hid_get_drvdata(hdev);
+        struct input_dev *input = field->hidinput->input;
+
+        if (usage->type == EV_KEY && value &&
+                        (((ssc->quirks & SAITEK_RELEASE_MODE_RAT7) &&
+                          usage->code - BTN_MOUSE == 10) ||
+                        ((ssc->quirks & SAITEK_RELEASE_MODE_MMO7) &&
+                         usage->code - BTN_MOUSE == 15))) {
+
+                input_report_key(input, usage->code, 1);
+
+                /* report missing release event */
+                input_report_key(input, usage->code, 0);
+
+                return 1;
+        }
+
+        return 0;
+}
+
 static const struct hid_device_id saitek_devices[] = {
-        { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_PS1000)},
+        { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_PS1000),
+                .driver_data = SAITEK_FIX_PS1000 },
+        { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_RAT7),
+                .driver_data = SAITEK_RELEASE_MODE_RAT7 },
+        { HID_USB_DEVICE(USB_VENDOR_ID_SAITEK, USB_DEVICE_ID_SAITEK_MMO7),
+                .driver_data = SAITEK_RELEASE_MODE_MMO7 },
         { }
 };
 
@@ -52,7 +189,10 @@ MODULE_DEVICE_TABLE(hid, saitek_devices);
 static struct hid_driver saitek_driver = {
         .name = "saitek",
         .id_table = saitek_devices,
-        .report_fixup = saitek_report_fixup
+        .probe = saitek_probe,
+        .report_fixup = saitek_report_fixup,
+        .raw_event = saitek_raw_event,
+        .event = saitek_event,
 };
 module_hid_driver(saitek_driver);