[eBeam PATCH 0/2] new USB eBeam input driver

[eBeam PATCH 0/2] new USB eBeam input driver

[Yann Cantin]

Hi,

New USB input driver for eBeam devices.

Currently supported (tested) :
- Luidia eBeam classic projection and edge projection models
- Nec "interactive solution" NP01Wi1 & NP01Wi2 for video-projectors.

There's others devices (includind re-branded ones) in the wild that
should be supported out of the box.

So, the code :

Patch 1 to blacklist the devices for hid generic-usb.

Patch 2 is the actual driver.

Notable stuff :
- use div64_s64 for portable 64/64-bits divisions.
- 13 sysfs custom files : 9 values for the transformation matrix,
  4 for xy ranges and a calibration trigger.

The module run fine with a 3.3.6 and a 3.5.0 kernel, both x86_32 and 64.

Thanks for your help.

[eBeam PATCH 1/2] hid: Blacklist eBeam devices

[Yann Cantin]

Signed-off-by: Yann Cantin <yann.cantin@laposte.net>
---
 drivers/hid/hid-core.c |    3 +++
 drivers/hid/hid-ids.h  |    3 +++
 2 files changed, 6 insertions(+)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 8bf8a64..b4b0baf 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1907,6 +1907,9 @@ static const struct hid_device_id hid_ignore_list[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_DELORME, USB_DEVICE_ID_DELORME_EM_LT20) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY, 0x0004) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY, 0x000a) },
+#if defined(CONFIG_INPUT_EBEAM_USB)
+	{ HID_USB_DEVICE(USB_VENDOR_ID_EFI, USB_DEVICE_ID_EFI_EBEAM) },
+#endif
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ESSENTIAL_REALITY, USB_DEVICE_ID_ESSENTIAL_REALITY_P5) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ETT, USB_DEVICE_ID_TC5UH) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_ETT, USB_DEVICE_ID_TC4UM) },
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 1dcb76f..93f5b83 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -271,6 +271,9 @@
 #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_7349	0x7349
 #define USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH_A001	0xa001
 
+#define USB_VENDOR_ID_EFI		0x2650
+#define USB_DEVICE_ID_EFI_EBEAM		0x1311
+
 #define USB_VENDOR_ID_ELECOM		0x056e
 #define USB_DEVICE_ID_ELECOM_BM084	0x0061
 
-- 
1.7.10

[eBeam PATCH 2/2] input: misc: New USB eBeam input driver.

[Yann Cantin]

Signed-off-by: Yann Cantin <yann.cantin@laposte.net>
---
 drivers/input/misc/Kconfig  |   22 ++
 drivers/input/misc/Makefile |    1 +
 drivers/input/misc/ebeam.c  |  750 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 773 insertions(+)
 create mode 100644 drivers/input/misc/ebeam.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 7c0f1ec..c226b83 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -83,6 +83,28 @@ config INPUT_BMA150
 	  To compile this driver as a module, choose M here: the
 	  module will be called bma150.
 
+config INPUT_EBEAM_USB
+	tristate "USB eBeam driver"
+	depends on USB_ARCH_HAS_HCD
+	select USB
+	help
+	  Say Y here if you have a USB eBeam pointing device and want to
+	  use it without any proprietary user space tools.
+
+	  Have a look at <http://sourceforge.net/projects/ebeam/> for
+	  a usage description and the required user-space tools.
+
+	  Supported devices :
+	    - Luidia eBeam Classic Projection and eBeam Edge Projection
+	    - Nec NP01Wi1 & NP01Wi2 interactive solution
+
+	  Supposed working devices, need test, may lack functionnality :
+	    - Luidia eBeam Edge Whiteboard and eBeam Engage
+	    - Hitachi Starboard FX-63, FX-77, FX-82, FX-77GII
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ebeam.
+
 config INPUT_PCSPKR
 	tristate "PC Speaker support"
 	depends on PCSPKR_PLATFORM
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 83fe6f5..2aa9813 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_INPUT_CMA3000_I2C)		+= cma3000_d0x_i2c.o
 obj-$(CONFIG_INPUT_COBALT_BTNS)		+= cobalt_btns.o
 obj-$(CONFIG_INPUT_DA9052_ONKEY)	+= da9052_onkey.o
 obj-$(CONFIG_INPUT_DM355EVM)		+= dm355evm_keys.o
+obj-$(CONFIG_INPUT_EBEAM_USB)		+= ebeam.o
 obj-$(CONFIG_INPUT_GP2A)		+= gp2ap002a00f.o
 obj-$(CONFIG_INPUT_GPIO_TILT_POLLED)	+= gpio_tilt_polled.o
 obj-$(CONFIG_HP_SDC_RTC)		+= hp_sdc_rtc.o
diff --git a/drivers/input/misc/ebeam.c b/drivers/input/misc/ebeam.c
new file mode 100644
index 0000000..098e3cf
--- /dev/null
+++ b/drivers/input/misc/ebeam.c
@@ -0,0 +1,750 @@
+/******************************************************************************
+ *
+ * eBeam driver
+ *
+ * Copyright (C) 2012 Yann Cantin (yann.cantin@laposte.net)
+ *
+ *	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.
+ *
+ *  based on
+ *
+ *	usbtouchscreen.c by Daniel Ritz <daniel.ritz@gmx.ch>
+ *	aiptek.c (sysfs/settings) by Chris Atenasio <chris@crud.net>
+ *				     Bryan W. Headley <bwheadley@earthlink.net>
+ *
+ *****************************************************************************/
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/math64.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/usb.h>
+#include <linux/usb/input.h>
+
+#define DRIVER_AUTHOR	"Yann Cantin <yann.cantin@laposte.net>"
+#define DRIVER_DESC	"USB eBeam Driver"
+
+/* Common values for eBeam devices */
+#define REPT_SIZE	8		/* packet size		  */
+#define MIN_RAW_X	0		/* raw coordinates ranges */
+#define MAX_RAW_X	0xFFFF
+#define MIN_RAW_Y	0
+#define MAX_RAW_Y	0xFFFF
+
+
+#define USB_VENDOR_ID_EFI	0x2650	/* Electronics For Imaging, Inc	*/
+#define USB_DEVICE_ID_EFI_EBEAM	0x1311	/* eBeam hardware :		*/
+					/*	Luidia Classic and Edge	*/
+					/*	Nec NP01Wi1 & NP01Wi2	*/
+
+#define EBEAM_BTN_TIP	0x1      /* tip    */
+#define EBEAM_BTN_LIT	0x2      /* little */
+#define EBEAM_BTN_BIG	0x4      /* big    */
+
+/* ebeam settings */
+struct ebeam_settings {
+	int min_x;	/* computed coordinates ranges for the input layer */
+	int max_x;
+	int min_y;
+	int max_y;
+
+	/* H matrix */
+	s64 h1;
+	s64 h2;
+	s64 h3;
+	s64 h4;
+	s64 h5;
+	s64 h6;
+	s64 h7;
+	s64 h8;
+	s64 h9;
+};
+
+/* ebeam device */
+struct ebeam_device {
+	unsigned char		 *data;
+	dma_addr_t		 data_dma;
+	unsigned char		 *buffer;
+	int			 buf_len;
+	struct urb		 *irq;
+	struct usb_interface	 *interface;
+	struct input_dev	 *input;
+	char			 name[128];
+	char			 phys[64];
+	void			 *priv;
+
+	struct ebeam_settings	 cursetting;	/* device's current settings */
+	struct ebeam_settings	 newsetting;	/* ... and new ones	     */
+
+	bool			 calibrated;	/* false : send raw	     */
+						/* true  : send computed     */
+
+	u16			 raw_x, raw_y;	/* raw coordinates	     */
+	int			 x, y;		/* computed coordinates      */
+	int			 btn_map;	/* internal buttons map      */
+};
+
+/* device types */
+enum {
+	DEVTYPE_EBEAM,
+};
+
+static const struct usb_device_id ebeam_devices[] = {
+	{USB_DEVICE(USB_VENDOR_ID_EFI, USB_DEVICE_ID_EFI_EBEAM),
+			.driver_info = DEVTYPE_EBEAM},
+	{}
+};
+
+static void ebeam_init_settings(struct ebeam_device *ebeam)
+{
+	ebeam->calibrated = false;
+
+	/* Init (x,y) min/max to raw ones */
+	ebeam->cursetting.min_x = ebeam->newsetting.min_x = MIN_RAW_X;
+	ebeam->cursetting.max_x = ebeam->newsetting.max_x = MAX_RAW_X;
+	ebeam->cursetting.min_y = ebeam->newsetting.min_y = MIN_RAW_Y;
+	ebeam->cursetting.max_y = ebeam->newsetting.max_y = MAX_RAW_Y;
+
+	/* Safe values for the H matrix (Identity) */
+	ebeam->cursetting.h1 = ebeam->newsetting.h1 = 1;
+	ebeam->cursetting.h2 = ebeam->newsetting.h2 = 0;
+	ebeam->cursetting.h3 = ebeam->newsetting.h3 = 0;
+
+	ebeam->cursetting.h4 = ebeam->newsetting.h4 = 0;
+	ebeam->cursetting.h5 = ebeam->newsetting.h5 = 1;
+	ebeam->cursetting.h6 = ebeam->newsetting.h6 = 0;
+
+	ebeam->cursetting.h7 = ebeam->newsetting.h7 = 0;
+	ebeam->cursetting.h8 = ebeam->newsetting.h8 = 0;
+	ebeam->cursetting.h9 = ebeam->newsetting.h9 = 1;
+}
+
+static void ebeam_setup_input(struct ebeam_device *ebeam,
+			      struct input_dev *input_dev)
+{
+	unsigned long flags;
+
+	/* Take event lock while modifying parameters */
+	spin_lock_irqsave(&input_dev->event_lock, flags);
+
+	/* Properties */
+	set_bit(INPUT_PROP_DIRECT,  input_dev->propbit);
+
+	/* Events generated */
+	set_bit(EV_KEY, input_dev->evbit);
+	set_bit(EV_ABS, input_dev->evbit);
+
+	/* Keys */
+	set_bit(BTN_LEFT,   input_dev->keybit);
+	set_bit(BTN_MIDDLE, input_dev->keybit);
+	set_bit(BTN_RIGHT,  input_dev->keybit);
+
+	/* Axis */
+	if (!ebeam->calibrated) {
+		ebeam->cursetting.min_x = MIN_RAW_X;
+		ebeam->cursetting.max_x = MAX_RAW_X;
+		ebeam->cursetting.min_y = MIN_RAW_Y;
+		ebeam->cursetting.max_y = MAX_RAW_Y;
+	}
+
+	input_set_abs_params(input_dev, ABS_X,
+			     ebeam->cursetting.min_x, ebeam->cursetting.max_x,
+			     0, 0);
+	input_set_abs_params(input_dev, ABS_Y,
+			     ebeam->cursetting.min_y, ebeam->cursetting.max_y,
+			     0, 0);
+
+	spin_unlock_irqrestore(&input_dev->event_lock, flags);
+}
+
+/*******************************************************************************
+ * sysfs part
+ */
+
+/*
+ * screen min/max and H matrix coefs
+ * _get return *current* value
+ * _set set new value
+ */
+#define DEVICE_MINMAX_ATTR(MM)						       \
+static ssize_t ebeam_##MM##_get(struct device *dev,			       \
+				struct device_attribute *attr,		       \
+				char *buf)				       \
+{									       \
+	struct ebeam_device *ebeam = dev_get_drvdata(dev);		       \
+									       \
+	return snprintf(buf, PAGE_SIZE, "%d\n", ebeam->cursetting.MM);	       \
+}									       \
+static ssize_t ebeam_##MM##_set(struct device *dev,			       \
+				struct device_attribute *attr,		       \
+				const char *buf,			       \
+				size_t count)				       \
+{									       \
+	struct ebeam_device *ebeam = dev_get_drvdata(dev);		       \
+	int err, MM;							       \
+									       \
+	err = kstrtoint(buf, 10, &MM);					       \
+	if (err)							       \
+		return err;						       \
+									       \
+	ebeam->newsetting.MM = MM;					       \
+	return count;							       \
+}									       \
+static DEVICE_ATTR(MM, S_IRUGO | S_IWUGO,				       \
+		   ebeam_##MM##_get,					       \
+		   ebeam_##MM##_set)
+
+DEVICE_MINMAX_ATTR(min_x);
+DEVICE_MINMAX_ATTR(max_x);
+DEVICE_MINMAX_ATTR(min_y);
+DEVICE_MINMAX_ATTR(max_y);
+
+#define DEVICE_H_ATTR(SET_ID)						       \
+static ssize_t ebeam_h##SET_ID##_get(struct device *dev,		       \
+				     struct device_attribute *attr,	       \
+				     char *buf)				       \
+{									       \
+	struct ebeam_device *ebeam = dev_get_drvdata(dev);		       \
+									       \
+	return snprintf(buf, PAGE_SIZE, "%lld\n", ebeam->cursetting.h##SET_ID);\
+}									       \
+static ssize_t ebeam_h##SET_ID##_set(struct device *dev,		       \
+				     struct device_attribute *attr,	       \
+				     const char *buf,			       \
+				     size_t count)			       \
+{									       \
+	struct ebeam_device *ebeam = dev_get_drvdata(dev);		       \
+	int err;							       \
+	u64 h;								       \
+									       \
+	err = kstrtoll(buf, 10, &h);					       \
+	if (err)							       \
+		return err;						       \
+									       \
+	ebeam->newsetting.h##SET_ID = h;				       \
+	return count;							       \
+}									       \
+static DEVICE_ATTR(h##SET_ID, S_IRUGO | S_IWUGO,			       \
+		   ebeam_h##SET_ID##_get,				       \
+		   ebeam_h##SET_ID##_set)
+
+DEVICE_H_ATTR(1);
+DEVICE_H_ATTR(2);
+DEVICE_H_ATTR(3);
+DEVICE_H_ATTR(4);
+DEVICE_H_ATTR(5);
+DEVICE_H_ATTR(6);
+DEVICE_H_ATTR(7);
+DEVICE_H_ATTR(8);
+DEVICE_H_ATTR(9);
+
+/*
+ * sysfs calibrated
+ * Once H matrix coefs are set, writing 1 to this file triggers
+ * coordinates mapping.
+ * Anything else reset the device to un-calibrated mode,
+ * storing cursetting in newsetting.
+*/
+static ssize_t ebeam_calibrated_get(struct device *dev,
+				    struct device_attribute *attr,
+				    char *buf)
+{
+	struct ebeam_device *ebeam = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", ebeam->calibrated);
+}
+
+static ssize_t ebeam_calibrated_set(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf,
+				    size_t count)
+{
+	struct ebeam_device *ebeam = dev_get_drvdata(dev);
+	int err, c;
+
+	err = kstrtoint(buf, 10, &c);
+	if (err)
+		return err;
+
+	if (c == 1) {
+		memcpy(&ebeam->cursetting, &ebeam->newsetting,
+		       sizeof(struct ebeam_settings));
+		ebeam->calibrated = true;
+		ebeam_setup_input(ebeam, ebeam->input);
+	} else {
+		memcpy(&ebeam->newsetting, &ebeam->cursetting,
+		       sizeof(struct ebeam_settings));
+		ebeam->calibrated = false;
+		ebeam_setup_input(ebeam, ebeam->input);
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR(calibrated, S_IRUGO | S_IWUGO,
+		   ebeam_calibrated_get, ebeam_calibrated_set);
+
+static struct attribute *ebeam_attrs[] = {
+	&dev_attr_min_x.attr,
+	&dev_attr_min_y.attr,
+	&dev_attr_max_x.attr,
+	&dev_attr_max_y.attr,
+	&dev_attr_h1.attr,
+	&dev_attr_h2.attr,
+	&dev_attr_h3.attr,
+	&dev_attr_h4.attr,
+	&dev_attr_h5.attr,
+	&dev_attr_h6.attr,
+	&dev_attr_h7.attr,
+	&dev_attr_h8.attr,
+	&dev_attr_h9.attr,
+	&dev_attr_calibrated.attr,
+	NULL
+};
+
+static const struct attribute_group ebeam_attr_group = {
+	.attrs = ebeam_attrs,
+};
+
+/* IRQ */
+static int ebeam_read_data(struct ebeam_device *ebeam, unsigned char *pkt)
+{
+
+/*
+ * Packet description : 8 bytes
+ *
+ *  nop packet : FF FF FF FF FF FF FF FF
+ *
+ *  pkt[0] : Sensors
+ *	bit 1 : ultrasound signal (guessed)
+ *	bit 2 : IR signal (tested with a remote...) ;
+ *	readings OK : 0x03 (anything else is a show-stopper)
+ *
+ *  pkt[1] : raw_x low
+ *  pkt[2] : raw_x high
+ *
+ *  pkt[3] : raw_y low
+ *  pkt[4] : raw_y high
+ *
+ *  pkt[5] : fiability ?
+ *	often 0xC0
+ *	> 0x80 : OK
+ *
+ *  pkt[6] :
+ *	buttons state (low 4 bits)
+ *		0x1 = no buttons
+ *		bit 0 : tip (WARNING inversed : 0=pressed)
+ *		bit 1 : ? (always 0 during tests)
+ *		bit 2 : little (1=pressed)
+ *		bit 3 : big (1=pressed)
+ *
+ *	pointer ID : (hight 4 bits)
+ *		Tested  : 0x6=wand ;
+ *		Guessed : 0x1=red ; 0x2=blue ; 0x3=green ; 0x4=black ;
+ *			  0x5=eraser
+ *		bit 4 : pointer ID
+ *		bit 5 : pointer ID
+ *		bit 6 : pointer ID
+ *		bit 7 : pointer ID
+ *
+ *
+ *  pkt[7] : fiability ?
+ *	often 0xFF
+ *
+ */
+
+	/* Filtering bad/nop packet */
+	if (pkt[0] != 0x03)
+		return 0;
+
+	ebeam->raw_x = (pkt[2] << 8) | pkt[1];
+	ebeam->raw_y = (pkt[4] << 8) | pkt[3];
+
+	ebeam->btn_map = (!(pkt[6] & 0x1))	|
+			 ((pkt[6] & 0x4) >> 1)	|
+			 ((pkt[6] & 0x8) >> 1);
+
+	return 1;
+}
+
+/*
+ * IRQ
+ * compute screen coordinates from raw
+ * Overflow and negative values are user space's problem
+ */
+static bool ebeam_calculate_xy(struct ebeam_device *ebeam)
+{
+	/* 64-bits divisions handled by div64_s64 */
+
+	s64 scale;
+
+	if (!ebeam->calibrated) {
+		ebeam->x = ebeam->raw_x;
+		ebeam->y = ebeam->raw_y;
+	} else {
+		scale = ebeam->cursetting.h7 * ebeam->raw_x +
+			ebeam->cursetting.h8 * ebeam->raw_y +
+			ebeam->cursetting.h9;
+
+		/* Who want a division by zero in kernel ? */
+		if (scale == 0) {
+			dev_err(&(ebeam->interface)->dev,
+				"%s - Division by zero, wrong calibration.\n",
+				__func__);
+			dev_err(&(ebeam->interface)->dev,
+				"%s - Resetting to un-calibrated mode.\n",
+				__func__);
+			ebeam->calibrated = false;
+			return 0;
+		}
+
+		/*
+		 * We *must* round the result, but can't do (int) (v1/v2 + 0.5)
+		 *
+		 * (int) (v1/v2 + 0.5) <=> (int) ( (2*v1 + v2)/(2*v2) )
+		 */
+		ebeam->x =
+			(int) div64_s64((((ebeam->cursetting.h1 * ebeam->raw_x +
+					   ebeam->cursetting.h2 * ebeam->raw_y +
+					   ebeam->cursetting.h3) << 1) + scale),
+					   (scale << 1));
+		ebeam->y =
+			(int) div64_s64((((ebeam->cursetting.h4 * ebeam->raw_x +
+					   ebeam->cursetting.h5 * ebeam->raw_y +
+					   ebeam->cursetting.h6) << 1) + scale),
+					   (scale << 1));
+	}
+
+	return 1;
+}
+
+/* IRQ */
+static void ebeam_report_input(struct ebeam_device *ebeam)
+{
+	input_report_key(ebeam->input, BTN_LEFT,
+			 (ebeam->btn_map & EBEAM_BTN_TIP));
+	input_report_key(ebeam->input, BTN_MIDDLE,
+			 (ebeam->btn_map & EBEAM_BTN_LIT));
+	input_report_key(ebeam->input, BTN_RIGHT,
+			 (ebeam->btn_map & EBEAM_BTN_BIG));
+
+	input_report_abs(ebeam->input, ABS_X, ebeam->x);
+	input_report_abs(ebeam->input, ABS_Y, ebeam->y);
+
+	input_sync(ebeam->input);
+}
+
+/* IRQ */
+static void ebeam_process_pkt(struct ebeam_device *ebeam,
+			      unsigned char *pkt, int len)
+{
+	if (!ebeam_read_data(ebeam, pkt))
+		return;
+
+	if (!ebeam_calculate_xy(ebeam))
+		return;
+
+	ebeam_report_input(ebeam);
+}
+
+/* IRQ
+ * handler */
+static void ebeam_irq(struct urb *urb)
+{
+	struct ebeam_device *ebeam = urb->context;
+	struct device *dev = &ebeam->interface->dev;
+	int retval;
+
+	switch (urb->status) {
+	case 0:
+		/* success */
+		break;
+	case -ETIME:
+		/* this urb is timing out */
+		dev_dbg(dev,
+			"%s - urb timed out - was the device unplugged?\n",
+			__func__);
+		return;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+	case -EPIPE:
+		/* this urb is terminated, clean up */
+		dev_dbg(dev, "%s - urb shutting down with status: %d\n",
+			__func__, urb->status);
+		return;
+	default:
+		dev_dbg(dev, "%s - nonzero urb status received: %d\n",
+			__func__, urb->status);
+		goto exit;
+	}
+
+	ebeam_process_pkt(ebeam, ebeam->data, urb->actual_length);
+
+exit:
+	usb_mark_last_busy(interface_to_usbdev(ebeam->interface));
+	retval = usb_submit_urb(urb, GFP_ATOMIC);
+	if (retval)
+		dev_err(dev, "%s - usb_submit_urb failed with result: %d\n",
+			__func__, retval);
+}
+
+static int ebeam_open(struct input_dev *input)
+{
+	struct ebeam_device *ebeam = input_get_drvdata(input);
+	int r;
+
+	ebeam->irq->dev = interface_to_usbdev(ebeam->interface);
+
+	r = usb_autopm_get_interface(ebeam->interface) ? -EIO : 0;
+	if (r < 0)
+		goto out;
+
+	if (usb_submit_urb(ebeam->irq, GFP_KERNEL)) {
+		r = -EIO;
+		goto out_put;
+	}
+
+	ebeam->interface->needs_remote_wakeup = 1;
+out_put:
+	usb_autopm_put_interface(ebeam->interface);
+out:
+	return r;
+}
+
+static void ebeam_close(struct input_dev *input)
+{
+	struct ebeam_device *ebeam = input_get_drvdata(input);
+	int r;
+
+	usb_kill_urb(ebeam->irq);
+
+	r = usb_autopm_get_interface(ebeam->interface);
+	ebeam->interface->needs_remote_wakeup = 0;
+
+	if (!r)
+		usb_autopm_put_interface(ebeam->interface);
+}
+
+static int ebeam_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct ebeam_device *ebeam = usb_get_intfdata(intf);
+
+	usb_kill_urb(ebeam->irq);
+
+	return 0;
+}
+
+static int ebeam_resume(struct usb_interface *intf)
+{
+	struct ebeam_device *ebeam = usb_get_intfdata(intf);
+	struct input_dev *input = ebeam->input;
+	int result = 0;
+
+	mutex_lock(&input->mutex);
+	if (input->users)
+		result = usb_submit_urb(ebeam->irq, GFP_NOIO);
+	mutex_unlock(&input->mutex);
+
+	return result;
+}
+
+static void ebeam_free_buffers(struct usb_device *udev,
+			       struct ebeam_device *ebeam)
+{
+	usb_free_coherent(udev, REPT_SIZE,
+			  ebeam->data, ebeam->data_dma);
+	kfree(ebeam->buffer);
+}
+
+static struct usb_endpoint_descriptor *
+ebeam_get_input_endpoint(struct usb_host_interface *interface)
+{
+	int i;
+
+	for (i = 0; i < interface->desc.bNumEndpoints; i++)
+		if (usb_endpoint_dir_in(&interface->endpoint[i].desc))
+			return &interface->endpoint[i].desc;
+
+	return NULL;
+}
+
+static int ebeam_probe(struct usb_interface *intf,
+		       const struct usb_device_id *id)
+{
+	struct ebeam_device *ebeam;
+	struct input_dev *input_dev;
+	struct usb_endpoint_descriptor *endpoint;
+	struct usb_device *udev = interface_to_usbdev(intf);
+	int err = -ENOMEM;
+
+	endpoint = ebeam_get_input_endpoint(intf->cur_altsetting);
+	if (!endpoint)
+		return -ENXIO;
+
+	ebeam = kzalloc(sizeof(struct ebeam_device), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!ebeam || !input_dev)
+		goto out_free;
+
+	ebeam_init_settings(ebeam);
+
+	ebeam->data = usb_alloc_coherent(udev, REPT_SIZE,
+					 GFP_KERNEL, &ebeam->data_dma);
+	if (!ebeam->data)
+		goto out_free;
+
+	ebeam->irq = usb_alloc_urb(0, GFP_KERNEL);
+	if (!ebeam->irq) {
+		dev_dbg(&intf->dev,
+			"%s - usb_alloc_urb failed: ebeam->irq\n", __func__);
+		goto out_free_buffers;
+	}
+
+	ebeam->interface = intf;
+	ebeam->input = input_dev;
+
+	/* setup name */
+	snprintf(ebeam->name, sizeof(ebeam->name),
+		 "USB eBeam %04x:%04x",
+		 le16_to_cpu(udev->descriptor.idVendor),
+		 le16_to_cpu(udev->descriptor.idProduct));
+
+	if (udev->manufacturer || udev->product) {
+		strlcat(ebeam->name,
+			" (",
+			sizeof(ebeam->name));
+
+		if (udev->manufacturer)
+			strlcat(ebeam->name,
+				udev->manufacturer,
+				sizeof(ebeam->name));
+
+		if (udev->product) {
+			if (udev->manufacturer)
+				strlcat(ebeam->name,
+					" ",
+					sizeof(ebeam->name));
+			strlcat(ebeam->name,
+				udev->product,
+				sizeof(ebeam->name));
+		}
+
+		if (strlcat(ebeam->name, ")", sizeof(ebeam->name))
+			>= sizeof(ebeam->name)) {
+			/* overflowed, closing ) anyway */
+			ebeam->name[sizeof(ebeam->name)-2] = ')';
+		}
+	}
+
+	/* usb tree */
+	usb_make_path(udev, ebeam->phys, sizeof(ebeam->phys));
+	strlcat(ebeam->phys, "/input0", sizeof(ebeam->phys));
+
+	/* input setup */
+	input_dev->name = ebeam->name;
+	input_dev->phys = ebeam->phys;
+	usb_to_input_id(udev, &input_dev->id);
+	input_dev->dev.parent = &intf->dev;
+
+	input_set_drvdata(input_dev, ebeam);
+
+	input_dev->open = ebeam_open;
+	input_dev->close = ebeam_close;
+
+	/* usb urb setup */
+	if (usb_endpoint_type(endpoint) == USB_ENDPOINT_XFER_INT)
+		usb_fill_int_urb(ebeam->irq, udev,
+			usb_rcvintpipe(udev, endpoint->bEndpointAddress),
+			ebeam->data, REPT_SIZE,
+			ebeam_irq, ebeam, endpoint->bInterval);
+	else
+		usb_fill_bulk_urb(ebeam->irq, udev,
+			usb_rcvbulkpipe(udev, endpoint->bEndpointAddress),
+			ebeam->data, REPT_SIZE,
+			ebeam_irq, ebeam);
+
+	ebeam->irq->dev = udev;
+	ebeam->irq->transfer_dma = ebeam->data_dma;
+	ebeam->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+	/* input final setup */
+	ebeam_setup_input(ebeam, input_dev);
+
+	err = input_register_device(ebeam->input);
+	if (err) {
+		dev_dbg(&intf->dev,
+			"%s - input_register_device failed, err: %d\n",
+			__func__, err);
+		goto out_free_urb;
+	}
+
+	/* usb final setup */
+	usb_set_intfdata(intf, ebeam);
+
+	/* sysfs setup */
+	err = sysfs_create_group(&intf->dev.kobj, &ebeam_attr_group);
+	if (err) {
+		dev_dbg(&intf->dev,
+			"%s - cannot create sysfs group, err: %d\n",
+			__func__, err);
+		goto out_unregister_input;
+	}
+
+	return 0;
+
+out_unregister_input:
+	input_unregister_device(input_dev);
+	input_dev = NULL;
+out_free_urb:
+	usb_free_urb(ebeam->irq);
+out_free_buffers:
+	ebeam_free_buffers(udev, ebeam);
+out_free:
+	input_free_device(input_dev);
+	kfree(ebeam);
+	return err;
+}
+
+static void ebeam_disconnect(struct usb_interface *intf)
+{
+	struct ebeam_device *ebeam = usb_get_intfdata(intf);
+
+	if (!ebeam)
+		return;
+
+	dev_dbg(&intf->dev,
+		"%s - ebeam is initialized, cleaning up\n", __func__);
+
+	usb_set_intfdata(intf, NULL);
+	/* this will stop IO via close */
+	input_unregister_device(ebeam->input);
+	sysfs_remove_group(&intf->dev.kobj, &ebeam_attr_group);
+	usb_free_urb(ebeam->irq);
+	ebeam_free_buffers(interface_to_usbdev(intf), ebeam);
+	kfree(ebeam);
+}
+
+MODULE_DEVICE_TABLE(usb, ebeam_devices);
+
+static struct usb_driver ebeam_driver = {
+	.name			= "ebeam",
+	.probe			= ebeam_probe,
+	.disconnect		= ebeam_disconnect,
+	.suspend		= ebeam_suspend,
+	.resume			= ebeam_resume,
+	.id_table		= ebeam_devices,
+	.supports_autosuspend	= 1,
+};
+
+module_usb_driver(ebeam_driver);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
-- 
1.7.10

Re: [eBeam PATCH 2/2] input: misc: New USB eBeam input driver.

[Oliver Neukum]

On Sunday 02 September 2012 00:52:03 Yann Cantin wrote:

Hi,

before we add yet another sysfs interface, we should ask whether calibration
isn't a problem that should be solved with a common API.

	Regards
		Oliver

> +static ssize_t ebeam_calibrated_set(struct device *dev,
> +                                   struct device_attribute *attr,
> +                                   const char *buf,
> +                                   size_t count)
> +{
> +       struct ebeam_device *ebeam = dev_get_drvdata(dev);
> +       int err, c;
> +
> +       err = kstrtoint(buf, 10, &c);
> +       if (err)
> +               return err;
> +
> +       if (c == 1) {
> +               memcpy(&ebeam->cursetting, &ebeam->newsetting,
> +                      sizeof(struct ebeam_settings));
> +               ebeam->calibrated = true;
> +               ebeam_setup_input(ebeam, ebeam->input);
> +       } else {
> +               memcpy(&ebeam->newsetting, &ebeam->cursetting,
> +                      sizeof(struct ebeam_settings));
> +               ebeam->calibrated = false;
> +               ebeam_setup_input(ebeam, ebeam->input);
> +       }
> +
> +       return count;
> +}
> +
> +static DEVICE_ATTR(calibrated, S_IRUGO | S_IWUGO,
> +                  ebeam_calibrated_get, ebeam_calibrated_set);
> +
> +static struct attribute *ebeam_attrs[] = {
> +       &dev_attr_min_x.attr,
> +       &dev_attr_min_y.attr,
> +       &dev_attr_max_x.attr,
> +       &dev_attr_max_y.attr,
> +       &dev_attr_h1.attr,
> +       &dev_attr_h2.attr,
> +       &dev_attr_h3.attr,
> +       &dev_attr_h4.attr,
> +       &dev_attr_h5.attr,
> +       &dev_attr_h6.attr,
> +       &dev_attr_h7.attr,
> +       &dev_attr_h8.attr,
> +       &dev_attr_h9.attr,
> +       &dev_attr_calibrated.attr,
> +       NULL
> +};
> +
-- 
- - - 
SUSE LINUX Products GmbH, GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer, HRB 16746 (AG Nürnberg) 
Maxfeldstraße 5                         
90409 Nürnberg 
Germany 
- - - 

Re: [eBeam PATCH 2/2] input: misc: New USB eBeam input driver.

[Yann Cantin]

Hi,

Le 05/09/2012 09:29, Oliver Neukum a écrit :
> before we add yet another sysfs interface, we should ask whether calibration
> isn't a problem that should be solved with a common API.

Short answer : no.

##
Long answer (may be oot) :

Existing calibration tools or procedures (in kernel modules or xorg) for absolute
devices deals with hardware axis mostly matching system's ones (X screen mainly), modulo
switching XY, inversion or simple tweaks. Plus you know from the beginning the ranges
used, and all parameters are stable.

eBeam device track an active stylus in his fov, usually on a whiteboard where a
video-projector cast the computer screen. It then compute the stylus's position
and send it to the kernel in his own fixed 2D cartesian coordinate system relative
to the device.

The device is by design mobile (you stuck it anywhere on the border of the
projection plane for a session), his axis never match screen's ones, neither in range
nor orientation. Even worse, due to projection artifact, the two coordinates
systems (ebeam and screen) can even not be linearly correlated.

Manufacturer's so-called drivers seems to use second order interpolations,
i use an homography transformation (which is the right mathematical tool for
the problem, and seems quicker) to transform between coordinates systems. Anyway,
this need lot of parameters.

As ebeams are the only devices to my knowledge that work that way, i don't think
a common API can be common, unless we mean an in-kernel generic purpose calibration
API for input devices (stellar away for me), or a userland one (where should it be
in the stack ?). Sincerely, this look overkill.

In the other hand, the actual ebeam module transformation feeding events subsys
works very well and expose straight and usable data to userland (xorg evdev for now,
and any program that can eat kernel's input data).

##

I understand the sysfs interface is a problem. Eventually, in last resort, i can reduce
it to 4 files : pass the 9 matrix parameters as one big string, removing min values. But
i think this obfuscate the api for a marginal gain.


-- 
Yann Cantin
A4FEB47F
--

Re: [eBeam PATCH 2/2] input: misc: New USB eBeam input driver.

[Oliver Neukum]

On Wednesday 05 September 2012 21:58:06 Yann Cantin wrote:

> As ebeams are the only devices to my knowledge that work that way, i don't think
> a common API can be common, unless we mean an in-kernel generic purpose calibration
> API for input devices (stellar away for me), or a userland one (where should it be
> in the stack ?). Sincerely, this look overkill.
> 
> In the other hand, the actual ebeam module transformation feeding events subsys
> works very well and expose straight and usable data to userland (xorg evdev for now,
> and any program that can eat kernel's input data).

OK, I see the problem. You have no other choice.
 
> ##
> 
> I understand the sysfs interface is a problem. Eventually, in last resort, i can reduce
> it to 4 files : pass the 9 matrix parameters as one big string, removing min values. But
> i think this obfuscate the api for a marginal gain.

That would be wrong. The problem is a specific API. If it needs to be done
at all, it better be done as cleanly as possible.

	Regards
		Oliver