+/*
+ * Force feedback support for Holtek On Line Grip based gamepads
+ *
+ * These include at least a Brazilian "Clone Joypad Super Power Fire"
+ * which uses vendor ID 0x1241 and identifies as "HOLTEK On Line Grip".
+ *
+ * Copyright (c) 2011 Anssi Hannula <anssi.hannula@iki.fi>
+ */
+
+/*
+ * 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/slab.h>
+#include <linux/usb.h>
+
+#include "hid-ids.h"
+
+#ifdef CONFIG_HOLTEK_FF
+#include "usbhid/usbhid.h"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Anssi Hannula <anssi.hannula@iki.fi>");
+MODULE_DESCRIPTION("Force feedback support for Holtek On Line Grip based devices");
+
+/*
+ * These commands and parameters are currently known:
+ *
+ * byte 0: command id:
+ * 01 set effect parameters
+ * 02 play specified effect
+ * 03 stop specified effect
+ * 04 stop all effects
+ * 06 stop all effects
+ * (the difference between 04 and 06 isn't known; win driver
+ * sends 06,04 on application init, and 06 otherwise)
+ *
+ * Commands 01 and 02 need to be sent as pairs, i.e. you need to send 01
+ * before each 02.
+ *
+ * The rest of the bytes are parameters. Command 01 takes all of them, and
+ * commands 02,03 take only the effect id.
+ *
+ * byte 1:
+ * bits 0-3: effect id:
+ * 1: very strong rumble
+ * 2: periodic rumble, short intervals
+ * 3: very strong rumble
+ * 4: periodic rumble, long intervals
+ * 5: weak periodic rumble, long intervals
+ * 6: weak periodic rumble, short intervals
+ * 7: periodic rumble, short intervals
+ * 8: strong periodic rumble, short intervals
+ * 9: very strong rumble
+ * a: causes an error
+ * b: very strong periodic rumble, very short intervals
+ * c-f: nothing
+ * bit 6: right (weak) motor enabled
+ * bit 7: left (strong) motor enabled
+ *
+ * bytes 2-3: time in milliseconds, big-endian
+ * bytes 5-6: unknown (win driver seems to use at least 10e0 with effect 1
+ * and 0014 with effect 6)
+ * byte 7:
+ * bits 0-3: effect magnitude
+ */
+
+#define HOLTEKFF_MSG_LENGTH 7
+
+static const u8 start_effect_1[] = { 0x02, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00 };
+static const u8 stop_all4[] = { 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+static const u8 stop_all6[] = { 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+
+struct holtekff_device {
+ struct hid_field *field;
+};
+
+static void holtekff_send(struct holtekff_device *holtekff,
+ struct hid_device *hid,
+ const u8 data[HOLTEKFF_MSG_LENGTH])
+{
+ int i;
+
+ for (i = 0; i < HOLTEKFF_MSG_LENGTH; i++) {
+ holtekff->field->value[i] = data[i];
+ }
+
+ dbg_hid("sending %02x %02x %02x %02x %02x %02x %02x\n", data[0],
+ data[1], data[2], data[3], data[4], data[5], data[6]);
+
+ usbhid_submit_report(hid, holtekff->field->report, USB_DIR_OUT);
+}
+
+static int holtekff_play(struct input_dev *dev, void *data,
+ struct ff_effect *effect)
+{
+ struct hid_device *hid = input_get_drvdata(dev);
+ struct holtekff_device *holtekff = data;
+ int left, right;
+ /* effect type 1, length 65535 msec */
+ u8 buf[HOLTEKFF_MSG_LENGTH] =
+ { 0x01, 0x01, 0xff, 0xff, 0x10, 0xe0, 0x00 };
+
+ left = effect->u.rumble.strong_magnitude;
+ right = effect->u.rumble.weak_magnitude;
+ dbg_hid("called with 0x%04x 0x%04x\n", left, right);
+
+ if (!left && !right) {
+ holtekff_send(holtekff, hid, stop_all6);
+ return 0;
+ }
+
+ if (left)
+ buf[1] |= 0x80;
+ if (right)
+ buf[1] |= 0x40;
+
+ /* The device takes a single magnitude, so we just sum them up. */
+ buf[6] = min(0xf, (left >> 12) + (right >> 12));
+
+ holtekff_send(holtekff, hid, buf);
+ holtekff_send(holtekff, hid, start_effect_1);
+
+ return 0;
+}
+
+static int holtekff_init(struct hid_device *hid)
+{
+ struct holtekff_device *holtekff;
+ struct hid_report *report;
+ struct hid_input *hidinput = list_entry(hid->inputs.next,
+ 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)) {
+ hid_err(hid, "no output report found\n");
+ return -ENODEV;
+ }
+
+ report = list_entry(report_list->next, struct hid_report, list);
+
+ if (report->maxfield < 1 || report->field[0]->report_count != 7) {
+ hid_err(hid, "unexpected output report layout\n");
+ return -ENODEV;
+ }
+
+ holtekff = kzalloc(sizeof(*holtekff), GFP_KERNEL);
+ if (!holtekff)
+ return -ENOMEM;
+
+ set_bit(FF_RUMBLE, dev->ffbit);
+
+ holtekff->field = report->field[0];
+
+ /* initialize the same way as win driver does */
+ holtekff_send(holtekff, hid, stop_all4);
+ holtekff_send(holtekff, hid, stop_all6);
+
+ error = input_ff_create_memless(dev, holtekff, holtekff_play);
+ if (error) {
+ kfree(holtekff);
+ return error;
+ }
+
+ hid_info(hid, "Force feedback for Holtek On Line Grip based devices by Anssi Hannula <anssi.hannula@iki.fi>\n");
+
+ return 0;
+}
+#else
+static inline int holtekff_init(struct hid_device *hid)
+{
+ return 0;
+}
+#endif
+
+static int holtek_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+ int ret;
+
+ ret = hid_parse(hdev);
+ if (ret) {
+ hid_err(hdev, "parse failed\n");
+ goto err;
+ }
+
+ ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
+ if (ret) {
+ hid_err(hdev, "hw start failed\n");
+ goto err;
+ }
+
+ holtekff_init(hdev);
+
+ return 0;
+err:
+ return ret;
+}
+
+static const struct hid_device_id holtek_devices[] = {
+ { HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK, USB_DEVICE_ID_HOLTEK_ON_LINE_GRIP) },
+ { }
+};
+MODULE_DEVICE_TABLE(hid, holtek_devices);
+
+static struct hid_driver holtek_driver = {
+ .name = "holtek",
+ .id_table = holtek_devices,
+ .probe = holtek_probe,
+};
+
+static int __init holtek_init(void)
+{
+ return hid_register_driver(&holtek_driver);
+}
+
+static void __exit holtek_exit(void)
+{
+ hid_unregister_driver(&holtek_driver);
+}
+
+module_init(holtek_init);
+module_exit(holtek_exit);
+