--- /dev/null
+/*
+ * Surface2.0/SUR40/PixelSense input driver
+ *
+ * Copyright (c) 2013 by Florian 'floe' Echtler <floe@butterbrot.org>
+ *
+ * Derived from the USB Skeleton driver 1.1,
+ * Copyright (c) 2003 Greg Kroah-Hartman (greg@kroah.com)
+ *
+ * and from the Apple USB BCM5974 multitouch driver,
+ * Copyright (c) 2008 Henrik Rydberg (rydberg@euromail.se)
+ *
+ * and from the generic hid-multitouch driver,
+ * Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/completion.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/printk.h>
+#include <linux/input-polldev.h>
+#include <linux/input/mt.h>
+#include <linux/usb/input.h>
+
+/* read 512 bytes from endpoint 0x86 -> get header + blobs */
+struct sur40_header {
+
+ __le16 type; /* always 0x0001 */
+ __le16 count; /* count of blobs (if 0: continue prev. packet) */
+
+ __le32 packet_id; /* unique ID for all packets in one frame */
+
+ __le32 timestamp; /* milliseconds (inc. by 16 or 17 each frame) */
+ __le32 unknown; /* "epoch?" always 02/03 00 00 00 */
+
+} __packed;
+
+struct sur40_blob {
+
+ __le16 blob_id;
+
+ u8 action; /* 0x02 = enter/exit, 0x03 = update (?) */
+ u8 unknown; /* always 0x01 or 0x02 (no idea what this is?) */
+
+ __le16 bb_pos_x; /* upper left corner of bounding box */
+ __le16 bb_pos_y;
+
+ __le16 bb_size_x; /* size of bounding box */
+ __le16 bb_size_y;
+
+ __le16 pos_x; /* finger tip position */
+ __le16 pos_y;
+
+ __le16 ctr_x; /* centroid position */
+ __le16 ctr_y;
+
+ __le16 axis_x; /* somehow related to major/minor axis, mostly: */
+ __le16 axis_y; /* axis_x == bb_size_y && axis_y == bb_size_x */
+
+ __le32 angle; /* orientation in radians relative to x axis -
+ actually an IEEE754 float, don't use in kernel */
+
+ __le32 area; /* size in pixels/pressure (?) */
+
+ u8 padding[32];
+
+} __packed;
+
+/* combined header/blob data */
+struct sur40_data {
+ struct sur40_header header;
+ struct sur40_blob blobs[];
+} __packed;
+
+
+/* version information */
+#define DRIVER_SHORT "sur40"
+#define DRIVER_AUTHOR "Florian 'floe' Echtler <floe@butterbrot.org>"
+#define DRIVER_DESC "Surface2.0/SUR40/PixelSense input driver"
+
+/* vendor and device IDs */
+#define ID_MICROSOFT 0x045e
+#define ID_SUR40 0x0775
+
+/* sensor resolution */
+#define SENSOR_RES_X 1920
+#define SENSOR_RES_Y 1080
+
+/* touch data endpoint */
+#define TOUCH_ENDPOINT 0x86
+
+/* polling interval (ms) */
+#define POLL_INTERVAL 10
+
+/* maximum number of contacts FIXME: this is a guess? */
+#define MAX_CONTACTS 64
+
+/* control commands */
+#define SUR40_GET_VERSION 0xb0 /* 12 bytes string */
+#define SUR40_UNKNOWN1 0xb3 /* 5 bytes */
+#define SUR40_UNKNOWN2 0xc1 /* 24 bytes */
+
+#define SUR40_GET_STATE 0xc5 /* 4 bytes state (?) */
+#define SUR40_GET_SENSORS 0xb1 /* 8 bytes sensors */
+
+/*
+ * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT
+ * here by mistake which is very likely to have corrupted the firmware EEPROM
+ * on two separate SUR40 devices. Thanks to Alan Stern who spotted this bug.
+ * Should you ever run into a similar problem, the background story to this
+ * incident and instructions on how to fix the corrupted EEPROM are available
+ * at https://floe.butterbrot.org/matrix/hacking/surface/brick.html
+*/
+
+struct sur40_state {
+
+ struct usb_device *usbdev;
+ struct device *dev;
+ struct input_polled_dev *input;
+
+ struct sur40_data *bulk_in_buffer;
+ size_t bulk_in_size;
+ u8 bulk_in_epaddr;
+
+ char phys[64];
+};
+
+static int sur40_command(struct sur40_state *dev,
+ u8 command, u16 index, void *buffer, u16 size)
+{
+ return usb_control_msg(dev->usbdev, usb_rcvctrlpipe(dev->usbdev, 0),
+ command,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+ 0x00, index, buffer, size, 1000);
+}
+
+/* Initialization routine, called from sur40_open */
+static int sur40_init(struct sur40_state *dev)
+{
+ int result;
+ u8 buffer[24];
+
+ /* stupidly replay the original MS driver init sequence */
+ result = sur40_command(dev, SUR40_GET_VERSION, 0x00, buffer, 12);
+ if (result < 0)
+ return result;
+
+ result = sur40_command(dev, SUR40_GET_VERSION, 0x01, buffer, 12);
+ if (result < 0)
+ return result;
+
+ result = sur40_command(dev, SUR40_GET_VERSION, 0x02, buffer, 12);
+ if (result < 0)
+ return result;
+
+ result = sur40_command(dev, SUR40_UNKNOWN2, 0x00, buffer, 24);
+ if (result < 0)
+ return result;
+
+ result = sur40_command(dev, SUR40_UNKNOWN1, 0x00, buffer, 5);
+ if (result < 0)
+ return result;
+
+ result = sur40_command(dev, SUR40_GET_VERSION, 0x03, buffer, 12);
+
+ /*
+ * Discard the result buffer - no known data inside except
+ * some version strings, maybe extract these sometime...
+ */
+
+ return result;
+}
+
+/*
+ * Callback routines from input_polled_dev
+ */
+
+/* Enable the device, polling will now start. */
+static void sur40_open(struct input_polled_dev *polldev)
+{
+ struct sur40_state *sur40 = polldev->private;
+
+ dev_dbg(sur40->dev, "open\n");
+ sur40_init(sur40);
+}
+
+/* Disable device, polling has stopped. */
+static void sur40_close(struct input_polled_dev *polldev)
+{
+ struct sur40_state *sur40 = polldev->private;
+
+ dev_dbg(sur40->dev, "close\n");
+ /*
+ * There is no known way to stop the device, so we simply
+ * stop polling.
+ */
+}
+
+/*
+ * This function is called when a whole contact has been processed,
+ * so that it can assign it to a slot and store the data there.
+ */
+static void sur40_report_blob(struct sur40_blob *blob, struct input_dev *input)
+{
+ int wide, major, minor;
+
+ int bb_size_x = le16_to_cpu(blob->bb_size_x);
+ int bb_size_y = le16_to_cpu(blob->bb_size_y);
+
+ int pos_x = le16_to_cpu(blob->pos_x);
+ int pos_y = le16_to_cpu(blob->pos_y);
+
+ int ctr_x = le16_to_cpu(blob->ctr_x);
+ int ctr_y = le16_to_cpu(blob->ctr_y);
+
+ int slotnum = input_mt_get_slot_by_key(input, blob->blob_id);
+ if (slotnum < 0 || slotnum >= MAX_CONTACTS)
+ return;
+
+ input_mt_slot(input, slotnum);
+ input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
+ wide = (bb_size_x > bb_size_y);
+ major = max(bb_size_x, bb_size_y);
+ minor = min(bb_size_x, bb_size_y);
+
+ input_report_abs(input, ABS_MT_POSITION_X, pos_x);
+ input_report_abs(input, ABS_MT_POSITION_Y, pos_y);
+ input_report_abs(input, ABS_MT_TOOL_X, ctr_x);
+ input_report_abs(input, ABS_MT_TOOL_Y, ctr_y);
+
+ /* TODO: use a better orientation measure */
+ input_report_abs(input, ABS_MT_ORIENTATION, wide);
+ input_report_abs(input, ABS_MT_TOUCH_MAJOR, major);
+ input_report_abs(input, ABS_MT_TOUCH_MINOR, minor);
+}
+
+/* core function: poll for new input data */
+static void sur40_poll(struct input_polled_dev *polldev)
+{
+
+ struct sur40_state *sur40 = polldev->private;
+ struct input_dev *input = polldev->input;
+ int result, bulk_read, need_blobs, packet_blobs, i;
+ u32 packet_id;
+
+ struct sur40_header *header = &sur40->bulk_in_buffer->header;
+ struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0];
+
+ dev_dbg(sur40->dev, "poll\n");
+
+ need_blobs = -1;
+
+ do {
+
+ /* perform a blocking bulk read to get data from the device */
+ result = usb_bulk_msg(sur40->usbdev,
+ usb_rcvbulkpipe(sur40->usbdev, sur40->bulk_in_epaddr),
+ sur40->bulk_in_buffer, sur40->bulk_in_size,
+ &bulk_read, 1000);
+
+ dev_dbg(sur40->dev, "received %d bytes\n", bulk_read);
+
+ if (result < 0) {
+ dev_err(sur40->dev, "error in usb_bulk_read\n");
+ return;
+ }
+
+ result = bulk_read - sizeof(struct sur40_header);
+
+ if (result % sizeof(struct sur40_blob) != 0) {
+ dev_err(sur40->dev, "transfer size mismatch\n");
+ return;
+ }
+
+ /* first packet? */
+ if (need_blobs == -1) {
+ need_blobs = le16_to_cpu(header->count);
+ dev_dbg(sur40->dev, "need %d blobs\n", need_blobs);
+ packet_id = header->packet_id;
+ }
+
+ /*
+ * Sanity check. when video data is also being retrieved, the
+ * packet ID will usually increase in the middle of a series
+ * instead of at the end.
+ */
+ if (packet_id != header->packet_id)
+ dev_warn(sur40->dev, "packet ID mismatch\n");
+
+ packet_blobs = result / sizeof(struct sur40_blob);
+ dev_dbg(sur40->dev, "received %d blobs\n", packet_blobs);
+
+ /* packets always contain at least 4 blobs, even if empty */
+ if (packet_blobs > need_blobs)
+ packet_blobs = need_blobs;
+
+ for (i = 0; i < packet_blobs; i++) {
+ need_blobs--;
+ dev_dbg(sur40->dev, "processing blob\n");
+ sur40_report_blob(&(inblob[i]), input);
+ }
+
+ } while (need_blobs > 0);
+
+ input_mt_sync_frame(input);
+ input_sync(input);
+}
+
+/* Initialize input device parameters. */
+static void sur40_input_setup(struct input_dev *input_dev)
+{
+ __set_bit(EV_KEY, input_dev->evbit);
+ __set_bit(EV_ABS, input_dev->evbit);
+
+ input_set_abs_params(input_dev, ABS_MT_POSITION_X,
+ 0, SENSOR_RES_X, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
+ 0, SENSOR_RES_Y, 0, 0);
+
+ input_set_abs_params(input_dev, ABS_MT_TOOL_X,
+ 0, SENSOR_RES_X, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_TOOL_Y,
+ 0, SENSOR_RES_Y, 0, 0);
+
+ /* max value unknown, but major/minor axis
+ * can never be larger than screen */
+ input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
+ 0, SENSOR_RES_X, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_TOUCH_MINOR,
+ 0, SENSOR_RES_Y, 0, 0);
+
+ input_set_abs_params(input_dev, ABS_MT_ORIENTATION, 0, 1, 0, 0);
+
+ input_mt_init_slots(input_dev, MAX_CONTACTS,
+ INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+}
+
+/* Check candidate USB interface. */
+static int sur40_probe(struct usb_interface *interface,
+ const struct usb_device_id *id)
+{
+ struct usb_device *usbdev = interface_to_usbdev(interface);
+ struct sur40_state *sur40;
+ struct usb_host_interface *iface_desc;
+ struct usb_endpoint_descriptor *endpoint;
+ struct input_polled_dev *poll_dev;
+ int error;
+
+ /* Check if we really have the right interface. */
+ iface_desc = &interface->altsetting[0];
+ if (iface_desc->desc.bInterfaceClass != 0xFF)
+ return -ENODEV;
+
+ /* Use endpoint #4 (0x86). */
+ endpoint = &iface_desc->endpoint[4].desc;
+ if (endpoint->bEndpointAddress != TOUCH_ENDPOINT)
+ return -ENODEV;
+
+ /* Allocate memory for our device state and initialize it. */
+ sur40 = kzalloc(sizeof(struct sur40_state), GFP_KERNEL);
+ if (!sur40)
+ return -ENOMEM;
+
+ poll_dev = input_allocate_polled_device();
+ if (!poll_dev) {
+ error = -ENOMEM;
+ goto err_free_dev;
+ }
+
+ /* Set up polled input device control structure */
+ poll_dev->private = sur40;
+ poll_dev->poll_interval = POLL_INTERVAL;
+ poll_dev->open = sur40_open;
+ poll_dev->poll = sur40_poll;
+ poll_dev->close = sur40_close;
+
+ /* Set up regular input device structure */
+ sur40_input_setup(poll_dev->input);
+
+ poll_dev->input->name = "Samsung SUR40";
+ usb_to_input_id(usbdev, &poll_dev->input->id);
+ usb_make_path(usbdev, sur40->phys, sizeof(sur40->phys));
+ strlcat(sur40->phys, "/input0", sizeof(sur40->phys));
+ poll_dev->input->phys = sur40->phys;
+ poll_dev->input->dev.parent = &interface->dev;
+
+ sur40->usbdev = usbdev;
+ sur40->dev = &interface->dev;
+ sur40->input = poll_dev;
+
+ /* use the bulk-in endpoint tested above */
+ sur40->bulk_in_size = usb_endpoint_maxp(endpoint);
+ sur40->bulk_in_epaddr = endpoint->bEndpointAddress;
+ sur40->bulk_in_buffer = kmalloc(sur40->bulk_in_size, GFP_KERNEL);
+ if (!sur40->bulk_in_buffer) {
+ dev_err(&interface->dev, "Unable to allocate input buffer.");
+ error = -ENOMEM;
+ goto err_free_polldev;
+ }
+
+ error = input_register_polled_device(poll_dev);
+ if (error) {
+ dev_err(&interface->dev,
+ "Unable to register polled input device.");
+ goto err_free_buffer;
+ }
+
+ /* we can register the device now, as it is ready */
+ usb_set_intfdata(interface, sur40);
+ dev_dbg(&interface->dev, "%s is now attached\n", DRIVER_DESC);
+
+ return 0;
+
+err_free_buffer:
+ kfree(sur40->bulk_in_buffer);
+err_free_polldev:
+ input_free_polled_device(sur40->input);
+err_free_dev:
+ kfree(sur40);
+
+ return error;
+}
+
+/* Unregister device & clean up. */
+static void sur40_disconnect(struct usb_interface *interface)
+{
+ struct sur40_state *sur40 = usb_get_intfdata(interface);
+
+ input_unregister_polled_device(sur40->input);
+ input_free_polled_device(sur40->input);
+ kfree(sur40->bulk_in_buffer);
+ kfree(sur40);
+
+ usb_set_intfdata(interface, NULL);
+ dev_dbg(&interface->dev, "%s is now disconnected\n", DRIVER_DESC);
+}
+
+static const struct usb_device_id sur40_table[] = {
+ { USB_DEVICE(ID_MICROSOFT, ID_SUR40) }, /* Samsung SUR40 */
+ { } /* terminating null entry */
+};
+MODULE_DEVICE_TABLE(usb, sur40_table);
+
+/* USB-specific object needed to register this driver with the USB subsystem. */
+static struct usb_driver sur40_driver = {
+ .name = DRIVER_SHORT,
+ .probe = sur40_probe,
+ .disconnect = sur40_disconnect,
+ .id_table = sur40_table,
+};
+
+module_usb_driver(sur40_driver);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
projects / ~andy / linux / commitdiff