HID: wiimote: add Nunchuk support

This moves the nunchuk parser over to an extension module. This allows to
make use of hotplugged Nunchuks instead of the old static parser.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

3 files changed, 205 insertions, 0 deletions

diff --git a/drivers/hid/hid-wiimote-core.c b/drivers/hid/hid-wiimote-core.c
index 90ea5a2565d4..dedf3c84e243 100644
--- a/drivers/hid/hid-wiimote-core.c
+++ b/drivers/hid/hid-wiimote-core.c
@@ -444,6 +444,8 @@ static __u8 wiimote_cmd_read_ext(struct wiimote_data *wdata, __u8 *rmem)
             rmem[3] == 0xff && rmem[4] == 0xff && rmem[5] == 0xff)
                 return WIIMOTE_EXT_NONE;
 
+        if (rmem[4] == 0x00 && rmem[5] == 0x00)
+                return WIIMOTE_EXT_NUNCHUK;
         if (rmem[4] == 0x04 && rmem[5] == 0x02)
                 return WIIMOTE_EXT_BALANCE_BOARD;
 
@@ -478,6 +480,9 @@ static bool wiimote_cmd_map_mp(struct wiimote_data *wdata, __u8 exttype)
 
         /* map MP with correct pass-through mode */
         switch (exttype) {
+        case WIIMOTE_EXT_NUNCHUK:
+                wmem = 0x05;
+                break;
         default:
                 wmem = 0x04;
                 break;
@@ -1034,6 +1039,7 @@ out_release:
 static const char *wiimote_exttype_names[WIIMOTE_EXT_NUM] = {
         [WIIMOTE_EXT_NONE] = "None",
         [WIIMOTE_EXT_UNKNOWN] = "Unknown",
+        [WIIMOTE_EXT_NUNCHUK] = "Nintendo Wii Nunchuk",
         [WIIMOTE_EXT_BALANCE_BOARD] = "Nintendo Wii Balance Board",
 };
 
diff --git a/drivers/hid/hid-wiimote-modules.c b/drivers/hid/hid-wiimote-modules.c
index 6239cd87f1ed..e4bcc098bdfd 100644
--- a/drivers/hid/hid-wiimote-modules.c
+++ b/drivers/hid/hid-wiimote-modules.c
@@ -789,6 +789,203 @@ static const struct wiimod_ops wiimod_ir = {
 };
 
 /*
+ * Nunchuk Extension
+ * The Nintendo Wii Nunchuk was the first official extension published by
+ * Nintendo. It provides two additional keys and a separate accelerometer. It
+ * can be hotplugged to standard Wii Remotes.
+ */
+
+enum wiimod_nunchuk_keys {
+        WIIMOD_NUNCHUK_KEY_C,
+        WIIMOD_NUNCHUK_KEY_Z,
+        WIIMOD_NUNCHUK_KEY_NUM,
+};
+
+static const __u16 wiimod_nunchuk_map[] = {
+        BTN_C,          /* WIIMOD_NUNCHUK_KEY_C */
+        BTN_Z,          /* WIIMOD_NUNCHUK_KEY_Z */
+};
+
+static void wiimod_nunchuk_in_ext(struct wiimote_data *wdata, const __u8 *ext)
+{
+        __s16 x, y, z, bx, by;
+
+        /*   Byte |   8    7 |  6    5 |  4    3 |  2 |  1  |
+         *   -----+----------+---------+---------+----+-----+
+         *    1   |              Button X <7:0>             |
+         *    2   |              Button Y <7:0>             |
+         *   -----+----------+---------+---------+----+-----+
+         *    3   |               Speed X <9:2>             |
+         *    4   |               Speed Y <9:2>             |
+         *    5   |               Speed Z <9:2>             |
+         *   -----+----------+---------+---------+----+-----+
+         *    6   | Z <1:0>  | Y <1:0> | X <1:0> | BC | BZ  |
+         *   -----+----------+---------+---------+----+-----+
+         * Button X/Y is the analog stick. Speed X, Y and Z are the
+         * accelerometer data in the same format as the wiimote's accelerometer.
+         * The 6th byte contains the LSBs of the accelerometer data.
+         * BC and BZ are the C and Z buttons: 0 means pressed
+         *
+         * If reported interleaved with motionp, then the layout changes. The
+         * 5th and 6th byte changes to:
+         *   -----+-----------------------------------+-----+
+         *    5   |            Speed Z <9:3>          | EXT |
+         *   -----+--------+-----+-----+----+----+----+-----+
+         *    6   |Z <2:1> |Y <1>|X <1>| BC | BZ | 0  |  0  |
+         *   -----+--------+-----+-----+----+----+----+-----+
+         * All three accelerometer values lose their LSB. The other data is
+         * still available but slightly moved.
+         *
+         * Center data for button values is 128. Center value for accelerometer
+         * values it 512 / 0x200
+         */
+
+        bx = ext[0];
+        by = ext[1];
+        bx -= 128;
+        by -= 128;
+
+        x = ext[2] << 2;
+        y = ext[3] << 2;
+        z = ext[4] << 2;
+
+        if (wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE) {
+                x |= (ext[5] >> 3) & 0x02;
+                y |= (ext[5] >> 4) & 0x02;
+                z &= ~0x4;
+                z |= (ext[5] >> 5) & 0x06;
+        } else {
+                x |= (ext[5] >> 2) & 0x03;
+                y |= (ext[5] >> 4) & 0x03;
+                z |= (ext[5] >> 6) & 0x03;
+        }
+
+        x -= 0x200;
+        y -= 0x200;
+        z -= 0x200;
+
+        input_report_abs(wdata->extension.input, ABS_HAT0X, bx);
+        input_report_abs(wdata->extension.input, ABS_HAT0Y, by);
+
+        input_report_abs(wdata->extension.input, ABS_RX, x);
+        input_report_abs(wdata->extension.input, ABS_RY, y);
+        input_report_abs(wdata->extension.input, ABS_RZ, z);
+
+        if (wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE) {
+                input_report_key(wdata->extension.input,
+                        wiimod_nunchuk_map[WIIMOD_NUNCHUK_KEY_Z],
+                        !(ext[5] & 0x04));
+                input_report_key(wdata->extension.input,
+                        wiimod_nunchuk_map[WIIMOD_NUNCHUK_KEY_C],
+                        !(ext[5] & 0x08));
+        } else {
+                input_report_key(wdata->extension.input,
+                        wiimod_nunchuk_map[WIIMOD_NUNCHUK_KEY_Z],
+                        !(ext[5] & 0x01));
+                input_report_key(wdata->extension.input,
+                        wiimod_nunchuk_map[WIIMOD_NUNCHUK_KEY_C],
+                        !(ext[5] & 0x02));
+        }
+
+        input_sync(wdata->extension.input);
+}
+
+static int wiimod_nunchuk_open(struct input_dev *dev)
+{
+        struct wiimote_data *wdata = input_get_drvdata(dev);
+        unsigned long flags;
+
+        spin_lock_irqsave(&wdata->state.lock, flags);
+        wdata->state.flags |= WIIPROTO_FLAG_EXT_USED;
+        wiiproto_req_drm(wdata, WIIPROTO_REQ_NULL);
+        spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+        return 0;
+}
+
+static void wiimod_nunchuk_close(struct input_dev *dev)
+{
+        struct wiimote_data *wdata = input_get_drvdata(dev);
+        unsigned long flags;
+
+        spin_lock_irqsave(&wdata->state.lock, flags);
+        wdata->state.flags &= ~WIIPROTO_FLAG_EXT_USED;
+        wiiproto_req_drm(wdata, WIIPROTO_REQ_NULL);
+        spin_unlock_irqrestore(&wdata->state.lock, flags);
+}
+
+static int wiimod_nunchuk_probe(const struct wiimod_ops *ops,
+                                struct wiimote_data *wdata)
+{
+        int ret, i;
+
+        wdata->extension.input = input_allocate_device();
+        if (!wdata->extension.input)
+                return -ENOMEM;
+
+        input_set_drvdata(wdata->extension.input, wdata);
+        wdata->extension.input->open = wiimod_nunchuk_open;
+        wdata->extension.input->close = wiimod_nunchuk_close;
+        wdata->extension.input->dev.parent = &wdata->hdev->dev;
+        wdata->extension.input->id.bustype = wdata->hdev->bus;
+        wdata->extension.input->id.vendor = wdata->hdev->vendor;
+        wdata->extension.input->id.product = wdata->hdev->product;
+        wdata->extension.input->id.version = wdata->hdev->version;
+        wdata->extension.input->name = WIIMOTE_NAME " Nunchuk";
+
+        set_bit(EV_KEY, wdata->extension.input->evbit);
+        for (i = 0; i < WIIMOD_NUNCHUK_KEY_NUM; ++i)
+                set_bit(wiimod_nunchuk_map[i],
+                        wdata->extension.input->keybit);
+
+        set_bit(EV_ABS, wdata->extension.input->evbit);
+        set_bit(ABS_HAT0X, wdata->extension.input->absbit);
+        set_bit(ABS_HAT0Y, wdata->extension.input->absbit);
+        input_set_abs_params(wdata->extension.input,
+                             ABS_HAT0X, -120, 120, 2, 4);
+        input_set_abs_params(wdata->extension.input,
+                             ABS_HAT0Y, -120, 120, 2, 4);
+        set_bit(ABS_RX, wdata->extension.input->absbit);
+        set_bit(ABS_RY, wdata->extension.input->absbit);
+        set_bit(ABS_RZ, wdata->extension.input->absbit);
+        input_set_abs_params(wdata->extension.input,
+                             ABS_RX, -500, 500, 2, 4);
+        input_set_abs_params(wdata->extension.input,
+                             ABS_RY, -500, 500, 2, 4);
+        input_set_abs_params(wdata->extension.input,
+                             ABS_RZ, -500, 500, 2, 4);
+
+        ret = input_register_device(wdata->extension.input);
+        if (ret)
+                goto err_free;
+
+        return 0;
+
+err_free:
+        input_free_device(wdata->extension.input);
+        wdata->extension.input = NULL;
+        return ret;
+}
+
+static void wiimod_nunchuk_remove(const struct wiimod_ops *ops,
+                                  struct wiimote_data *wdata)
+{
+        if (!wdata->extension.input)
+                return;
+
+        input_unregister_device(wdata->extension.input);
+        wdata->extension.input = NULL;
+}
+
+static const struct wiimod_ops wiimod_nunchuk = {
+        .flags = 0,
+        .arg = 0,
+        .probe = wiimod_nunchuk_probe,
+        .remove = wiimod_nunchuk_remove,
+        .in_ext = wiimod_nunchuk_in_ext,
+};
+
+/*
  * Balance Board Extension
  * The Nintendo Wii Balance Board provides four hardware weight sensor plus a
  * single push button. No other peripherals are available. However, the
@@ -1026,5 +1223,6 @@ const struct wiimod_ops *wiimod_table[WIIMOD_NUM] = {
 const struct wiimod_ops *wiimod_ext_table[WIIMOTE_EXT_NUM] = {
         [WIIMOTE_EXT_NONE] = &wiimod_dummy,
         [WIIMOTE_EXT_UNKNOWN] = &wiimod_dummy,
+        [WIIMOTE_EXT_NUNCHUK] = &wiimod_nunchuk,
         [WIIMOTE_EXT_BALANCE_BOARD] = &wiimod_bboard,
 };
diff --git a/drivers/hid/hid-wiimote.h b/drivers/hid/hid-wiimote.h
index 8d314ae429b6..3414e4cdc4ff 100644
--- a/drivers/hid/hid-wiimote.h
+++ b/drivers/hid/hid-wiimote.h
@@ -80,6 +80,7 @@ enum wiimote_devtype {
 enum wiimote_exttype {
         WIIMOTE_EXT_NONE,
         WIIMOTE_EXT_UNKNOWN,
+        WIIMOTE_EXT_NUNCHUK,
         WIIMOTE_EXT_BALANCE_BOARD,
         WIIMOTE_EXT_NUM,
 };