Merge branch 'master' into for-linus

4 files changed, 446 insertions, 25 deletions

diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
index 7c662ee594a..be5c14a5a0a 100644
--- a/drivers/input/joystick/Kconfig
+++ b/drivers/input/joystick/Kconfig
@@ -193,6 +193,18 @@ config JOYSTICK_TWIDJOY
 	  To compile this driver as a module, choose M here: the
 	  module will be called twidjoy.
 
+config JOYSTICK_ZHENHUA
+	tristate "5-byte Zhenhua RC transmitter"
+	select SERIO
+	help
+	  Say Y here if you have a Zhen Hua PPM-4CH transmitter which is
+	  supplied with a ready to fly micro electric indoor helicopters
+	  such as EasyCopter, Lama, MiniCopter, DragonFly or Jabo and want
+	  to use it via serial cable as a joystick.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called zhenhua.
+
 config JOYSTICK_DB9
 	tristate "Multisystem, Sega Genesis, Saturn joysticks and gamepads"
 	depends on PARPORT
diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
index e855abb0cc5..fdbf8c4c287 100644
--- a/drivers/input/joystick/Makefile
+++ b/drivers/input/joystick/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_JOYSTICK_GF2K)		+= gf2k.o
 obj-$(CONFIG_JOYSTICK_GRIP)		+= grip.o
 obj-$(CONFIG_JOYSTICK_GRIP_MP)		+= grip_mp.o
 obj-$(CONFIG_JOYSTICK_GUILLEMOT)	+= guillemot.o
+obj-$(CONFIG_JOYSTICK_IFORCE)		+= iforce/
 obj-$(CONFIG_JOYSTICK_INTERACT)		+= interact.o
 obj-$(CONFIG_JOYSTICK_JOYDUMP)		+= joydump.o
 obj-$(CONFIG_JOYSTICK_MAGELLAN)		+= magellan.o
@@ -27,5 +28,5 @@ obj-$(CONFIG_JOYSTICK_TURBOGRAFX)	+= turbografx.o
 obj-$(CONFIG_JOYSTICK_TWIDJOY)		+= twidjoy.o
 obj-$(CONFIG_JOYSTICK_WARRIOR)		+= warrior.o
 obj-$(CONFIG_JOYSTICK_XPAD)		+= xpad.o
+obj-$(CONFIG_JOYSTICK_ZHENHUA)		+= zhenhua.o
 
-obj-$(CONFIG_JOYSTICK_IFORCE)		+= iforce/
diff --git a/drivers/input/joystick/xpad.c b/drivers/input/joystick/xpad.c
index 0380597249b..52ddb04644a 100644
--- a/drivers/input/joystick/xpad.c
+++ b/drivers/input/joystick/xpad.c
@@ -1,5 +1,5 @@
 /*
- * X-Box gamepad - v0.0.6
+ * X-Box gamepad driver
  *
  * Copyright (c) 2002 Marko Friedemann <mfr@bmx-chemnitz.de>
  *               2004 Oliver Schwartz <Oliver.Schwartz@gmx.de>,
@@ -68,6 +68,8 @@
  *  - dance pads will map D-PAD to buttons, not axes
  *  - pass the module paramater 'dpad_to_buttons' to force
  *    the D-PAD to map to buttons if your pad is not detected
+ *
+ * Later changes can be tracked in SCM.
  */
 
 #include <linux/kernel.h>
@@ -77,7 +79,6 @@
 #include <linux/module.h>
 #include <linux/usb/input.h>
 
-#define DRIVER_VERSION "v0.0.6"
 #define DRIVER_AUTHOR "Marko Friedemann <mfr@bmx-chemnitz.de>"
 #define DRIVER_DESC "X-Box pad driver"
 
@@ -87,10 +88,12 @@
    but we map them to axes when possible to simplify things */
 #define MAP_DPAD_TO_BUTTONS    0
 #define MAP_DPAD_TO_AXES       1
-#define MAP_DPAD_UNKNOWN       -1
+#define MAP_DPAD_UNKNOWN       2
 
 #define XTYPE_XBOX        0
 #define XTYPE_XBOX360     1
+#define XTYPE_XBOX360W    2
+#define XTYPE_UNKNOWN     3
 
 static int dpad_to_buttons;
 module_param(dpad_to_buttons, bool, S_IRUGO);
@@ -107,8 +110,10 @@ static const struct xpad_device {
 	{ 0x045e, 0x0289, "Microsoft X-Box pad v2 (US)", MAP_DPAD_TO_AXES, XTYPE_XBOX },
 	{ 0x045e, 0x0285, "Microsoft X-Box pad (Japan)", MAP_DPAD_TO_AXES, XTYPE_XBOX },
 	{ 0x045e, 0x0287, "Microsoft Xbox Controller S", MAP_DPAD_TO_AXES, XTYPE_XBOX },
+	{ 0x045e, 0x0719, "Xbox 360 Wireless Receiver", MAP_DPAD_TO_BUTTONS, XTYPE_XBOX360W },
 	{ 0x0c12, 0x8809, "RedOctane Xbox Dance Pad", MAP_DPAD_TO_BUTTONS, XTYPE_XBOX },
 	{ 0x044f, 0x0f07, "Thrustmaster, Inc. Controller", MAP_DPAD_TO_AXES, XTYPE_XBOX },
+	{ 0x046d, 0xc242, "Logitech Chillstream Controller", MAP_DPAD_TO_AXES, XTYPE_XBOX360 },
 	{ 0x046d, 0xca84, "Logitech Xbox Cordless Controller", MAP_DPAD_TO_AXES, XTYPE_XBOX },
 	{ 0x046d, 0xca88, "Logitech Compact Controller for Xbox", MAP_DPAD_TO_AXES, XTYPE_XBOX },
 	{ 0x05fd, 0x1007, "Mad Catz Controller (unverified)", MAP_DPAD_TO_AXES, XTYPE_XBOX },
@@ -135,18 +140,26 @@ static const struct xpad_device {
 	{ 0x0f30, 0x8888, "BigBen XBMiniPad Controller", MAP_DPAD_TO_AXES, XTYPE_XBOX },
 	{ 0x102c, 0xff0c, "Joytech Wireless Advanced Controller", MAP_DPAD_TO_AXES, XTYPE_XBOX },
 	{ 0x12ab, 0x8809, "Xbox DDR dancepad", MAP_DPAD_TO_BUTTONS, XTYPE_XBOX },
+	{ 0x1430, 0x4748, "RedOctane Guitar Hero X-plorer", MAP_DPAD_TO_AXES, XTYPE_XBOX360 },
 	{ 0x1430, 0x8888, "TX6500+ Dance Pad (first generation)", MAP_DPAD_TO_BUTTONS, XTYPE_XBOX },
 	{ 0x045e, 0x028e, "Microsoft X-Box 360 pad", MAP_DPAD_TO_AXES, XTYPE_XBOX360 },
 	{ 0xffff, 0xffff, "Chinese-made Xbox Controller", MAP_DPAD_TO_AXES, XTYPE_XBOX },
-	{ 0x0000, 0x0000, "Generic X-Box pad", MAP_DPAD_UNKNOWN, XTYPE_XBOX }
+	{ 0x0000, 0x0000, "Generic X-Box pad", MAP_DPAD_UNKNOWN, XTYPE_UNKNOWN }
 };
 
-static const signed short xpad_btn[] = {
-	BTN_A, BTN_B, BTN_C, BTN_X, BTN_Y, BTN_Z,	/* "analog" buttons */
+/* buttons shared with xbox and xbox360 */
+static const signed short xpad_common_btn[] = {
+	BTN_A, BTN_B, BTN_X, BTN_Y,			/* "analog" buttons */
 	BTN_START, BTN_BACK, BTN_THUMBL, BTN_THUMBR,	/* start/back/sticks */
 	-1						/* terminating entry */
 };
 
+/* original xbox controllers only */
+static const signed short xpad_btn[] = {
+	BTN_C, BTN_Z,		/* "analog" buttons */
+	-1			/* terminating entry */
+};
+
 /* only used if MAP_DPAD_TO_BUTTONS */
 static const signed short xpad_btn_pad[] = {
 	BTN_LEFT, BTN_RIGHT,		/* d-pad left, right */
@@ -173,12 +186,27 @@ static const signed short xpad_abs_pad[] = {
 	-1			/* terminating entry */
 };
 
-/* Xbox 360 has a vendor-specific (sub)class, so we cannot match it with only
- * USB_INTERFACE_INFO, more to that this device has 4 InterfaceProtocols,
- * but we need only one of them. */
+/* Xbox 360 has a vendor-specific class, so we cannot match it with only
+ * USB_INTERFACE_INFO (also specifically refused by USB subsystem), so we
+ * match against vendor id as well. Wired Xbox 360 devices have protocol 1,
+ * wireless controllers have protocol 129. */
+#define XPAD_XBOX360_VENDOR_PROTOCOL(vend,pr) \
+	.match_flags = USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_INT_INFO, \
+	.idVendor = (vend), \
+	.bInterfaceClass = USB_CLASS_VENDOR_SPEC, \
+	.bInterfaceSubClass = 93, \
+	.bInterfaceProtocol = (pr)
+#define XPAD_XBOX360_VENDOR(vend) \
+	{ XPAD_XBOX360_VENDOR_PROTOCOL(vend,1) }, \
+	{ XPAD_XBOX360_VENDOR_PROTOCOL(vend,129) }
+
 static struct usb_device_id xpad_table [] = {
 	{ USB_INTERFACE_INFO('X', 'B', 0) },	/* X-Box USB-IF not approved class */
-	{ USB_DEVICE_INTERFACE_PROTOCOL(0x045e, 0x028e, 1) },	/* X-Box 360 controller */
+	XPAD_XBOX360_VENDOR(0x045e),		/* Microsoft X-Box 360 controllers */
+	XPAD_XBOX360_VENDOR(0x046d),		/* Logitech X-Box 360 style controllers */
+	XPAD_XBOX360_VENDOR(0x0738),		/* Mad Catz X-Box 360 controllers */
+	XPAD_XBOX360_VENDOR(0x0e6f),		/* 0x0e6f X-Box 360 controllers */
+	XPAD_XBOX360_VENDOR(0x1430),		/* RedOctane X-Box 360 controllers */
 	{ }
 };
 
@@ -188,10 +216,15 @@ struct usb_xpad {
 	struct input_dev *dev;		/* input device interface */
 	struct usb_device *udev;	/* usb device */
 
+	int pad_present;
+
 	struct urb *irq_in;		/* urb for interrupt in report */
 	unsigned char *idata;		/* input data */
 	dma_addr_t idata_dma;
 
+	struct urb *bulk_out;
+	unsigned char *bdata;
+
 #if defined(CONFIG_JOYSTICK_XPAD_FF) || defined(CONFIG_JOYSTICK_XPAD_LEDS)
 	struct urb *irq_out;		/* urb for interrupt out report */
 	unsigned char *odata;		/* output data */
@@ -227,13 +260,13 @@ static void xpad_process_packet(struct usb_xpad *xpad, u16 cmd, unsigned char *d
 	input_report_abs(dev, ABS_X,
 			 (__s16) le16_to_cpup((__le16 *)(data + 12)));
 	input_report_abs(dev, ABS_Y,
-			 (__s16) le16_to_cpup((__le16 *)(data + 14)));
+			 ~(__s16) le16_to_cpup((__le16 *)(data + 14)));
 
 	/* right stick */
 	input_report_abs(dev, ABS_RX,
 			 (__s16) le16_to_cpup((__le16 *)(data + 16)));
 	input_report_abs(dev, ABS_RY,
-			 (__s16) le16_to_cpup((__le16 *)(data + 18)));
+			 ~(__s16) le16_to_cpup((__le16 *)(data + 18)));
 
 	/* triggers left/right */
 	input_report_abs(dev, ABS_Z, data[10]);
@@ -321,13 +354,13 @@ static void xpad360_process_packet(struct usb_xpad *xpad,
 	input_report_abs(dev, ABS_X,
 			 (__s16) le16_to_cpup((__le16 *)(data + 6)));
 	input_report_abs(dev, ABS_Y,
-			 (__s16) le16_to_cpup((__le16 *)(data + 8)));
+			 ~(__s16) le16_to_cpup((__le16 *)(data + 8)));
 
 	/* right stick */
 	input_report_abs(dev, ABS_RX,
 			 (__s16) le16_to_cpup((__le16 *)(data + 10)));
 	input_report_abs(dev, ABS_RY,
-			 (__s16) le16_to_cpup((__le16 *)(data + 12)));
+			 ~(__s16) le16_to_cpup((__le16 *)(data + 12)));
 
 	/* triggers left/right */
 	input_report_abs(dev, ABS_Z, data[4]);
@@ -336,6 +369,39 @@ static void xpad360_process_packet(struct usb_xpad *xpad,
 	input_sync(dev);
 }
 
+/*
+ * xpad360w_process_packet
+ *
+ * Completes a request by converting the data into events for the
+ * input subsystem. It is version for xbox 360 wireless controller.
+ *
+ * Byte.Bit
+ * 00.1 - Status change: The controller or headset has connected/disconnected
+ *                       Bits 01.7 and 01.6 are valid
+ * 01.7 - Controller present
+ * 01.6 - Headset present
+ * 01.1 - Pad state (Bytes 4+) valid
+ *
+ */
+
+static void xpad360w_process_packet(struct usb_xpad *xpad, u16 cmd, unsigned char *data)
+{
+	/* Presence change */
+	if (data[0] & 0x08) {
+		if (data[1] & 0x80) {
+			xpad->pad_present = 1;
+			usb_submit_urb(xpad->bulk_out, GFP_ATOMIC);
+		} else
+			xpad->pad_present = 0;
+	}
+
+	/* Valid pad data */
+	if (!(data[1] & 0x1))
+		return;
+
+	xpad360_process_packet(xpad, cmd, &data[4]);
+}
+
 static void xpad_irq_in(struct urb *urb)
 {
 	struct usb_xpad *xpad = urb->context;
@@ -358,10 +424,16 @@ static void xpad_irq_in(struct urb *urb)
 		goto exit;
 	}
 
-	if (xpad->xtype == XTYPE_XBOX360)
+	switch (xpad->xtype) {
+	case XTYPE_XBOX360:
 		xpad360_process_packet(xpad, 0, xpad->idata);
-	else
+		break;
+	case XTYPE_XBOX360W:
+		xpad360w_process_packet(xpad, 0, xpad->idata);
+		break;
+	default:
 		xpad_process_packet(xpad, 0, xpad->idata);
+	}
 
 exit:
 	retval = usb_submit_urb (urb, GFP_ATOMIC);
@@ -399,6 +471,23 @@ exit:
 		    __FUNCTION__, retval);
 }
 
+static void xpad_bulk_out(struct urb *urb)
+{
+	switch (urb->status) {
+	case 0:
+		/* success */
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		/* this urb is terminated, clean up */
+		dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
+		break;
+	default:
+		dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
+	}
+}
+
 static int xpad_init_output(struct usb_interface *intf, struct usb_xpad *xpad)
 {
 	struct usb_endpoint_descriptor *ep_irq_out;
@@ -408,7 +497,7 @@ static int xpad_init_output(struct usb_interface *intf, struct usb_xpad *xpad)
 		return 0;
 
 	xpad->odata = usb_buffer_alloc(xpad->udev, XPAD_PKT_LEN,
-				       GFP_ATOMIC, &xpad->odata_dma );
+				       GFP_KERNEL, &xpad->odata_dma);
 	if (!xpad->odata)
 		goto fail1;
 
@@ -469,6 +558,7 @@ static int xpad_play_effect(struct input_dev *dev, void *data,
 		xpad->odata[5] = 0x00;
 		xpad->odata[6] = 0x00;
 		xpad->odata[7] = 0x00;
+		xpad->irq_out->transfer_buffer_length = 8;
 		usb_submit_urb(xpad->irq_out, GFP_KERNEL);
 	}
 
@@ -477,6 +567,9 @@ static int xpad_play_effect(struct input_dev *dev, void *data,
 
 static int xpad_init_ff(struct usb_xpad *xpad)
 {
+	if (xpad->xtype != XTYPE_XBOX360)
+		return 0;
+
 	input_set_capability(xpad->dev, EV_FF, FF_RUMBLE);
 
 	return input_ff_create_memless(xpad->dev, NULL, xpad_play_effect);
@@ -502,6 +595,7 @@ static void xpad_send_led_command(struct usb_xpad *xpad, int command)
 		xpad->odata[0] = 0x01;
 		xpad->odata[1] = 0x03;
 		xpad->odata[2] = command;
+		xpad->irq_out->transfer_buffer_length = 3;
 		usb_submit_urb(xpad->irq_out, GFP_KERNEL);
 		mutex_unlock(&xpad->odata_mutex);
 	}
@@ -574,6 +668,10 @@ static int xpad_open(struct input_dev *dev)
 {
 	struct usb_xpad *xpad = input_get_drvdata(dev);
 
+	/* URB was submitted in probe */
+	if(xpad->xtype == XTYPE_XBOX360W)
+		return 0;
+
 	xpad->irq_in->dev = xpad->udev;
 	if (usb_submit_urb(xpad->irq_in, GFP_KERNEL))
 		return -EIO;
@@ -585,7 +683,8 @@ static void xpad_close(struct input_dev *dev)
 {
 	struct usb_xpad *xpad = input_get_drvdata(dev);
 
-	usb_kill_urb(xpad->irq_in);
+	if(xpad->xtype != XTYPE_XBOX360W)
+		usb_kill_urb(xpad->irq_in);
 	xpad_stop_output(xpad);
 }
 
@@ -632,7 +731,7 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id
 		goto fail1;
 
 	xpad->idata = usb_buffer_alloc(udev, XPAD_PKT_LEN,
-				       GFP_ATOMIC, &xpad->idata_dma);
+				       GFP_KERNEL, &xpad->idata_dma);
 	if (!xpad->idata)
 		goto fail1;
 
@@ -644,7 +743,16 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id
 	xpad->dpad_mapping = xpad_device[i].dpad_mapping;
 	xpad->xtype = xpad_device[i].xtype;
 	if (xpad->dpad_mapping == MAP_DPAD_UNKNOWN)
-		xpad->dpad_mapping = dpad_to_buttons;
+		xpad->dpad_mapping = !dpad_to_buttons;
+	if (xpad->xtype == XTYPE_UNKNOWN) {
+		if (intf->cur_altsetting->desc.bInterfaceClass == USB_CLASS_VENDOR_SPEC) {
+			if (intf->cur_altsetting->desc.bInterfaceProtocol == 129)
+				xpad->xtype = XTYPE_XBOX360W;
+			else
+				xpad->xtype = XTYPE_XBOX360;
+		} else
+			xpad->xtype = XTYPE_XBOX;
+	}
 	xpad->dev = input_dev;
 	usb_make_path(udev, xpad->phys, sizeof(xpad->phys));
 	strlcat(xpad->phys, "/input0", sizeof(xpad->phys));
@@ -662,11 +770,14 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id
 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 
 	/* set up buttons */
-	for (i = 0; xpad_btn[i] >= 0; i++)
-		set_bit(xpad_btn[i], input_dev->keybit);
-	if (xpad->xtype == XTYPE_XBOX360)
+	for (i = 0; xpad_common_btn[i] >= 0; i++)
+		set_bit(xpad_common_btn[i], input_dev->keybit);
+	if ((xpad->xtype == XTYPE_XBOX360) || (xpad->xtype == XTYPE_XBOX360W))
 		for (i = 0; xpad360_btn[i] >= 0; i++)
 			set_bit(xpad360_btn[i], input_dev->keybit);
+	else
+		for (i = 0; xpad_btn[i] >= 0; i++)
+			set_bit(xpad_btn[i], input_dev->keybit);
 	if (xpad->dpad_mapping == MAP_DPAD_TO_BUTTONS)
 		for (i = 0; xpad_btn_pad[i] >= 0; i++)
 			set_bit(xpad_btn_pad[i], input_dev->keybit);
@@ -703,8 +814,57 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id
 		goto fail4;
 
 	usb_set_intfdata(intf, xpad);
+
+	/*
+	 * Submit the int URB immediatly rather than waiting for open
+	 * because we get status messages from the device whether
+	 * or not any controllers are attached.  In fact, it's
+	 * exactly the message that a controller has arrived that
+	 * we're waiting for.
+	 */
+	if (xpad->xtype == XTYPE_XBOX360W) {
+		xpad->irq_in->dev = xpad->udev;
+		error = usb_submit_urb(xpad->irq_in, GFP_KERNEL);
+		if (error)
+			goto fail4;
+
+		/*
+		 * Setup the message to set the LEDs on the
+		 * controller when it shows up
+		 */
+		xpad->bulk_out = usb_alloc_urb(0, GFP_KERNEL);
+		if(!xpad->bulk_out)
+			goto fail5;
+
+		xpad->bdata = kzalloc(XPAD_PKT_LEN, GFP_KERNEL);
+		if(!xpad->bdata)
+			goto fail6;
+
+		xpad->bdata[2] = 0x08;
+		switch (intf->cur_altsetting->desc.bInterfaceNumber) {
+		case 0:
+			xpad->bdata[3] = 0x42;
+			break;
+		case 2:
+			xpad->bdata[3] = 0x43;
+			break;
+		case 4:
+			xpad->bdata[3] = 0x44;
+			break;
+		case 6:
+			xpad->bdata[3] = 0x45;
+		}
+
+		ep_irq_in = &intf->cur_altsetting->endpoint[1].desc;
+		usb_fill_bulk_urb(xpad->bulk_out, udev,
+				usb_sndbulkpipe(udev, ep_irq_in->bEndpointAddress),
+				xpad->bdata, XPAD_PKT_LEN, xpad_bulk_out, xpad);
+	}
+
 	return 0;
 
+ fail6:	usb_free_urb(xpad->bulk_out);
+ fail5:	usb_kill_urb(xpad->irq_in);
  fail4:	usb_free_urb(xpad->irq_in);
  fail3:	xpad_deinit_output(xpad);
  fail2:	usb_buffer_free(udev, XPAD_PKT_LEN, xpad->idata, xpad->idata_dma);
@@ -723,6 +883,11 @@ static void xpad_disconnect(struct usb_interface *intf)
 		xpad_led_disconnect(xpad);
 		input_unregister_device(xpad->dev);
 		xpad_deinit_output(xpad);
+		if (xpad->xtype == XTYPE_XBOX360W) {
+			usb_kill_urb(xpad->bulk_out);
+			usb_free_urb(xpad->bulk_out);
+			usb_kill_urb(xpad->irq_in);
+		}
 		usb_free_urb(xpad->irq_in);
 		usb_buffer_free(xpad->udev, XPAD_PKT_LEN,
 				xpad->idata, xpad->idata_dma);
@@ -741,7 +906,7 @@ static int __init usb_xpad_init(void)
 {
 	int result = usb_register(&xpad_driver);
 	if (result == 0)
-		info(DRIVER_DESC ":" DRIVER_VERSION);
+		info(DRIVER_DESC);
 	return result;
 }
 
diff --git a/drivers/input/joystick/zhenhua.c b/drivers/input/joystick/zhenhua.c
new file mode 100644
index 00000000000..b5853125c89
--- /dev/null
+++ b/drivers/input/joystick/zhenhua.c
@@ -0,0 +1,243 @@
+/*
+ *  derived from "twidjoy.c"
+ *
+ *  Copyright (c) 2008 Martin Kebert
+ *  Copyright (c) 2001 Arndt Schoenewald
+ *  Copyright (c) 2000-2001 Vojtech Pavlik
+ *  Copyright (c) 2000 Mark Fletcher
+ *
+ */
+
+/*
+ * Driver to use 4CH RC transmitter using Zhen Hua 5-byte protocol (Walkera Lama,
+ * EasyCopter etc.) as a joystick under Linux.
+ *
+ * RC transmitters using Zhen Hua 5-byte protocol are cheap four channels
+ * transmitters for control a RC planes or RC helicopters with possibility to
+ * connect on a serial port.
+ * Data coming from transmitter is in this order:
+ * 1. byte = synchronisation byte
+ * 2. byte = X axis
+ * 3. byte = Y axis
+ * 4. byte = RZ axis
+ * 5. byte = Z axis
+ * (and this is repeated)
+ *
+ * For questions or feedback regarding this driver module please contact:
+ * Martin Kebert <gkmarty@gmail.com> - but I am not a C-programmer nor kernel
+ * coder :-(
+ */
+
+/*
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/serio.h>
+#include <linux/init.h>
+
+#define DRIVER_DESC	"RC transmitter with 5-byte Zhen Hua protocol joystick driver"
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/*
+ * Constants.
+ */
+
+#define ZHENHUA_MAX_LENGTH 5
+
+/*
+ * Zhen Hua data.
+ */
+
+struct zhenhua {
+	struct input_dev *dev;
+	int idx;
+	unsigned char data[ZHENHUA_MAX_LENGTH];
+	char phys[32];
+};
+
+
+/* bits in all incoming bytes needs to be "reversed" */
+static int zhenhua_bitreverse(int x)
+{
+	x = ((x & 0xaa) >> 1) | ((x & 0x55) << 1);
+	x = ((x & 0xcc) >> 2) | ((x & 0x33) << 2);
+	x = ((x & 0xf0) >> 4) | ((x & 0x0f) << 4);
+	return x;
+}
+
+/*
+ * zhenhua_process_packet() decodes packets the driver receives from the
+ * RC transmitter. It updates the data accordingly.
+ */
+
+static void zhenhua_process_packet(struct zhenhua *zhenhua)
+{
+	struct input_dev *dev = zhenhua->dev;
+	unsigned char *data = zhenhua->data;
+
+	input_report_abs(dev, ABS_Y, data[1]);
+	input_report_abs(dev, ABS_X, data[2]);
+	input_report_abs(dev, ABS_RZ, data[3]);
+	input_report_abs(dev, ABS_Z, data[4]);
+
+	input_sync(dev);
+}
+
+/*
+ * zhenhua_interrupt() is called by the low level driver when characters
+ * are ready for us. We then buffer them for further processing, or call the
+ * packet processing routine.
+ */
+
+static irqreturn_t zhenhua_interrupt(struct serio *serio, unsigned char data, unsigned int flags)
+{
+	struct zhenhua *zhenhua = serio_get_drvdata(serio);
+
+	/* All Zhen Hua packets are 5 bytes. The fact that the first byte
+	 * is allways 0xf7 and all others are in range 0x32 - 0xc8 (50-200)
+	 * can be used to check and regain sync. */
+
+	if (data == 0xef)
+		zhenhua->idx = 0;	/* this byte starts a new packet */
+	else if (zhenhua->idx == 0)
+		return IRQ_HANDLED;	/* wrong MSB -- ignore this byte */
+
+	if (zhenhua->idx < ZHENHUA_MAX_LENGTH)
+		zhenhua->data[zhenhua->idx++] = zhenhua_bitreverse(data);
+
+	if (zhenhua->idx == ZHENHUA_MAX_LENGTH) {
+		zhenhua_process_packet(zhenhua);
+		zhenhua->idx = 0;
+	}
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * zhenhua_disconnect() is the opposite of zhenhua_connect()
+ */
+
+static void zhenhua_disconnect(struct serio *serio)
+{
+	struct zhenhua *zhenhua = serio_get_drvdata(serio);
+
+	serio_close(serio);
+	serio_set_drvdata(serio, NULL);
+	input_unregister_device(zhenhua->dev);
+	kfree(zhenhua);
+}
+
+/*
+ * zhenhua_connect() is the routine that is called when someone adds a
+ * new serio device. It looks for the Twiddler, and if found, registers
+ * it as an input device.
+ */
+
+static int zhenhua_connect(struct serio *serio, struct serio_driver *drv)
+{
+	struct zhenhua *zhenhua;
+	struct input_dev *input_dev;
+	int err = -ENOMEM;
+
+	zhenhua = kzalloc(sizeof(struct zhenhua), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!zhenhua || !input_dev)
+		goto fail1;
+
+	zhenhua->dev = input_dev;
+	snprintf(zhenhua->phys, sizeof(zhenhua->phys), "%s/input0", serio->phys);
+
+	input_dev->name = "Zhen Hua 5-byte device";
+	input_dev->phys = zhenhua->phys;
+	input_dev->id.bustype = BUS_RS232;
+	input_dev->id.vendor = SERIO_ZHENHUA;
+	input_dev->id.product = 0x0001;
+	input_dev->id.version = 0x0100;
+	input_dev->dev.parent = &serio->dev;
+
+	input_dev->evbit[0] = BIT(EV_ABS);
+	input_set_abs_params(input_dev, ABS_X, 50, 200, 0, 0);
+	input_set_abs_params(input_dev, ABS_Y, 50, 200, 0, 0);
+	input_set_abs_params(input_dev, ABS_Z, 50, 200, 0, 0);
+	input_set_abs_params(input_dev, ABS_RZ, 50, 200, 0, 0);
+
+	serio_set_drvdata(serio, zhenhua);
+
+	err = serio_open(serio, drv);
+	if (err)
+		goto fail2;
+
+	err = input_register_device(zhenhua->dev);
+	if (err)
+		goto fail3;
+
+	return 0;
+
+ fail3:	serio_close(serio);
+ fail2:	serio_set_drvdata(serio, NULL);
+ fail1:	input_free_device(input_dev);
+	kfree(zhenhua);
+	return err;
+}
+
+/*
+ * The serio driver structure.
+ */
+
+static struct serio_device_id zhenhua_serio_ids[] = {
+	{
+		.type	= SERIO_RS232,
+		.proto	= SERIO_ZHENHUA,
+		.id	= SERIO_ANY,
+		.extra	= SERIO_ANY,
+	},
+	{ 0 }
+};
+
+MODULE_DEVICE_TABLE(serio, zhenhua_serio_ids);
+
+static struct serio_driver zhenhua_drv = {
+	.driver		= {
+		.name	= "zhenhua",
+	},
+	.description	= DRIVER_DESC,
+	.id_table	= zhenhua_serio_ids,
+	.interrupt	= zhenhua_interrupt,
+	.connect	= zhenhua_connect,
+	.disconnect	= zhenhua_disconnect,
+};
+
+/*
+ * The functions for inserting/removing us as a module.
+ */
+
+static int __init zhenhua_init(void)
+{
+	return serio_register_driver(&zhenhua_drv);
+}
+
+static void __exit zhenhua_exit(void)
+{
+	serio_unregister_driver(&zhenhua_drv);
+}
+
+module_init(zhenhua_init);
+module_exit(zhenhua_exit);