HID: Add Force Feedback support for EMS Trio Linker Plus II

The device has connections for GameCube, PlayStation 2 and Dreamcast
controllers, however Force Feedback is only supported for PS2 and GC
controllers.

When using a PS2 controller it may be necessary to press the "Analog" button to
enable support for both motors (this behavior is identical to the Windows
driver, I have found no way to avoid that).

Signed-off-by: Ignaz Forster <ignaz.forster@gmx.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

5 files changed, 177 insertions, 0 deletions

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 3052e2969ad0..3d9a95f28aea 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -150,6 +150,16 @@ config DRAGONRISE_FF
         Say Y here if you want to enable force feedback support for DragonRise Inc.
         game controllers.
 
+config HID_EMS_FF
+        tristate "EMS Production Inc. force feedback support"
+        depends on USB_HID
+        select INPUT_FF_MEMLESS
+        ---help---
+        Say Y here if you want to enable force feedback support for devices by
+        EMS Production Ltd.
+        Currently the following devices are known to be supported:
+         - Trio Linker Plus II
+
 config HID_EGALAX
         tristate "eGalax multi-touch panel"
         depends on USB_HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index c335605b9200..86192f67d7c2 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_HID_CHERRY)	+= hid-cherry.o
 obj-$(CONFIG_HID_CHICONY)       += hid-chicony.o
 obj-$(CONFIG_HID_CYPRESS)       += hid-cypress.o
 obj-$(CONFIG_HID_DRAGONRISE)    += hid-drff.o
+obj-$(CONFIG_HID_EMS_FF)        += hid-emsff.o
 obj-$(CONFIG_HID_EGALAX)        += hid-egalax.o
 obj-$(CONFIG_HID_ELECOM)        += hid-elecom.o
 obj-$(CONFIG_HID_EZKEY)         += hid-ezkey.o
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 7832b6e2478b..b3393e17b375 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1301,6 +1301,7 @@ static const struct hid_device_id hid_blacklist[] = {
         { HID_USB_DEVICE(USB_VENDOR_ID_DWAV, USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH) },
         { HID_USB_DEVICE(USB_VENDOR_ID_DWAV, USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH1) },
         { HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ELECOM, USB_DEVICE_ID_ELECOM_BM084) },
+        { HID_USB_DEVICE(USB_VENDOR_ID_EMS, USB_DEVICE_ID_EMS_TRIO_LINKER_PLUS_II) },
         { HID_USB_DEVICE(USB_VENDOR_ID_EZKEY, USB_DEVICE_ID_BTC_8193) },
         { HID_USB_DEVICE(USB_VENDOR_ID_GAMERON, USB_DEVICE_ID_GAMERON_DUAL_PSX_ADAPTOR) },
         { HID_USB_DEVICE(USB_VENDOR_ID_GAMERON, USB_DEVICE_ID_GAMERON_DUAL_PCS_ADAPTOR) },
diff --git a/drivers/hid/hid-emsff.c b/drivers/hid/hid-emsff.c
new file mode 100644
index 000000000000..c61b192d7cff
--- /dev/null
+++ b/drivers/hid/hid-emsff.c
@@ -0,0 +1,162 @@
+/*
+ *  Force feedback support for EMS Trio Linker Plus II
+ *
+ *  Copyright (c) 2010 Ignaz Forster <ignaz.forster@gmx.de>
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+
+#include <linux/hid.h>
+#include <linux/input.h>
+#include <linux/usb.h>
+
+#include "hid-ids.h"
+#include "usbhid/usbhid.h"
+
+struct emsff_device {
+        struct hid_report *report;
+};
+
+static int emsff_play(struct input_dev *dev, void *data,
+                         struct ff_effect *effect)
+{
+        struct hid_device *hid = input_get_drvdata(dev);
+        struct emsff_device *emsff = data;
+        int weak, strong;
+
+        weak = effect->u.rumble.weak_magnitude;
+        strong = effect->u.rumble.strong_magnitude;
+
+        dbg_hid("called with 0x%04x 0x%04x\n", strong, weak);
+
+        weak = weak * 0xff / 0xffff;
+        strong = strong * 0xff / 0xffff;
+
+        emsff->report->field[0]->value[1] = weak;
+        emsff->report->field[0]->value[2] = strong;
+
+        dbg_hid("running with 0x%02x 0x%02x\n", strong, weak);
+        usbhid_submit_report(hid, emsff->report, USB_DIR_OUT);
+
+        return 0;
+}
+
+static int emsff_init(struct hid_device *hid)
+{
+        struct emsff_device *emsff;
+        struct hid_report *report;
+        struct hid_input *hidinput = list_first_entry(&hid->inputs,
+                                                struct hid_input, list);
+        struct list_head *report_list =
+                        &hid->report_enum[HID_OUTPUT_REPORT].report_list;
+        struct input_dev *dev = hidinput->input;
+        int error;
+
+        if (list_empty(report_list)) {
+                dev_err(&hid->dev, "no output reports found\n");
+                return -ENODEV;
+        }
+
+        report = list_first_entry(report_list, struct hid_report, list);
+        if (report->maxfield < 1) {
+                dev_err(&hid->dev, "no fields in the report\n");
+                return -ENODEV;
+        }
+
+        if (report->field[0]->report_count < 7) {
+                dev_err(&hid->dev, "not enough values in the field\n");
+                return -ENODEV;
+        }
+
+        emsff = kzalloc(sizeof(struct emsff_device), GFP_KERNEL);
+        if (!emsff)
+                return -ENOMEM;
+
+        set_bit(FF_RUMBLE, dev->ffbit);
+
+        error = input_ff_create_memless(dev, emsff, emsff_play);
+        if (error) {
+                kfree(emsff);
+                return error;
+        }
+
+        emsff->report = report;
+        emsff->report->field[0]->value[0] = 0x01;
+        emsff->report->field[0]->value[1] = 0x00;
+        emsff->report->field[0]->value[2] = 0x00;
+        emsff->report->field[0]->value[3] = 0x00;
+        emsff->report->field[0]->value[4] = 0x00;
+        emsff->report->field[0]->value[5] = 0x00;
+        emsff->report->field[0]->value[6] = 0x00;
+        usbhid_submit_report(hid, emsff->report, USB_DIR_OUT);
+
+        dev_info(&hid->dev, "force feedback for EMS based devices by "
+               "Ignaz Forster <ignaz.forster@gmx.de>\n");
+
+        return 0;
+}
+
+static int ems_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+        int ret;
+
+        ret = hid_parse(hdev);
+        if (ret) {
+                dev_err(&hdev->dev, "parse failed\n");
+                goto err;
+        }
+
+        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
+        if (ret) {
+                dev_err(&hdev->dev, "hw start failed\n");
+                goto err;
+        }
+
+        emsff_init(hdev);
+
+        return 0;
+err:
+        return ret;
+}
+
+static const struct hid_device_id ems_devices[] = {
+        { HID_USB_DEVICE(USB_VENDOR_ID_EMS, 0x118) },
+        { }
+};
+MODULE_DEVICE_TABLE(hid, ems_devices);
+
+static struct hid_driver ems_driver = {
+        .name = "hkems",
+        .id_table = ems_devices,
+        .probe = ems_probe,
+};
+
+static int ems_init(void)
+{
+        return hid_register_driver(&ems_driver);
+}
+
+static void ems_exit(void)
+{
+        hid_unregister_driver(&ems_driver);
+}
+
+module_init(ems_init);
+module_exit(ems_exit);
+MODULE_LICENSE("GPL");
+
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 3ee999d33004..68114dbcd895 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -203,6 +203,9 @@
 #define USB_VENDOR_ID_ELO               0x04E7
 #define USB_DEVICE_ID_ELO_TS2700        0x0020
 
+#define USB_VENDOR_ID_EMS               0x2006
+#define USB_DEVICE_ID_EMS_TRIO_LINKER_PLUS_II 0x0118
+
 #define USB_VENDOR_ID_ESSENTIAL_REALITY 0x0d7f
 #define USB_DEVICE_ID_ESSENTIAL_REALITY_P5 0x0100