/*
 * drivers/input/tablet/wacom_sys.c
 *
 *  USB Wacom tablet support - system specific code
 */

/*
 * 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 "wacom_wac.h"
#include "wacom.h"

/* defines to get HID report descriptor */
#define HID_DEVICET_HID         (USB_TYPE_CLASS | 0x01)
#define HID_DEVICET_REPORT      (USB_TYPE_CLASS | 0x02)
#define HID_USAGE_UNDEFINED             0x00
#define HID_USAGE_PAGE                  0x05
#define HID_USAGE_PAGE_DIGITIZER        0x0d
#define HID_USAGE_PAGE_DESKTOP          0x01
#define HID_USAGE                       0x09
#define HID_USAGE_X                     0x30
#define HID_USAGE_Y                     0x31
#define HID_USAGE_X_TILT                0x3d
#define HID_USAGE_Y_TILT                0x3e
#define HID_USAGE_FINGER                0x22
#define HID_USAGE_STYLUS                0x20
#define HID_USAGE_CONTACTMAX            0x55
#define HID_COLLECTION                  0xa1
#define HID_COLLECTION_LOGICAL          0x02
#define HID_COLLECTION_END              0xc0

enum {
        WCM_UNDEFINED = 0,
        WCM_DESKTOP,
        WCM_DIGITIZER,
};

struct hid_descriptor {
        struct usb_descriptor_header header;
        __le16   bcdHID;
        u8       bCountryCode;
        u8       bNumDescriptors;
        u8       bDescriptorType;
        __le16   wDescriptorLength;
} __attribute__ ((packed));

/* defines to get/set USB message */
#define USB_REQ_GET_REPORT      0x01
#define USB_REQ_SET_REPORT      0x09

#define WAC_HID_FEATURE_REPORT  0x03
#define WAC_MSG_RETRIES         5

#define WAC_CMD_LED_CONTROL     0x20
#define WAC_CMD_ICON_START      0x21
#define WAC_CMD_ICON_XFER       0x23
#define WAC_CMD_RETRIES         10

static int wacom_get_report(struct usb_interface *intf, u8 type, u8 id,
                            void *buf, size_t size, unsigned int retries)
{
        struct usb_device *dev = interface_to_usbdev(intf);
        int retval;

        do {
                retval = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
                                USB_REQ_GET_REPORT,
                                USB_DIR_IN | USB_TYPE_CLASS |
                                USB_RECIP_INTERFACE,
                                (type << 8) + id,
                                intf->altsetting[0].desc.bInterfaceNumber,
                                buf, size, 100);
        } while ((retval == -ETIMEDOUT || retval == -EPIPE) && --retries);

        return retval;
}

static int wacom_set_report(struct usb_interface *intf, u8 type, u8 id,
                            void *buf, size_t size, unsigned int retries)
{
        struct usb_device *dev = interface_to_usbdev(intf);
        int retval;

        do {
                retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
                                USB_REQ_SET_REPORT,
                                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                                (type << 8) + id,
                                intf->altsetting[0].desc.bInterfaceNumber,
                                buf, size, 1000);
        } while ((retval == -ETIMEDOUT || retval == -EPIPE) && --retries);

        return retval;
}

static void wacom_sys_irq(struct urb *urb)
{
        struct wacom *wacom = urb->context;
        struct device *dev = &wacom->intf->dev;
        int retval;

        switch (urb->status) {
        case 0:
                /* success */
                break;
        case -ECONNRESET:
        case -ENOENT:
        case -ESHUTDOWN:
                /* 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;
        }

        wacom_wac_irq(&wacom->wacom_wac, urb->actual_length);

 exit:
        usb_mark_last_busy(wacom->usbdev);
        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 wacom_open(struct input_dev *dev)
{
        struct wacom *wacom = input_get_drvdata(dev);
        int retval = 0;

        if (usb_autopm_get_interface(wacom->intf) < 0)
                return -EIO;

        mutex_lock(&wacom->lock);

        if (usb_submit_urb(wacom->irq, GFP_KERNEL)) {
                retval = -EIO;
                goto out;
        }

        wacom->open = true;
        wacom->intf->needs_remote_wakeup = 1;

out:
        mutex_unlock(&wacom->lock);
        usb_autopm_put_interface(wacom->intf);
        return retval;
}

static void wacom_close(struct input_dev *dev)
{
        struct wacom *wacom = input_get_drvdata(dev);
        int autopm_error;

        autopm_error = usb_autopm_get_interface(wacom->intf);

        mutex_lock(&wacom->lock);
        usb_kill_urb(wacom->irq);
        wacom->open = false;
        wacom->intf->needs_remote_wakeup = 0;
        mutex_unlock(&wacom->lock);

        if (!autopm_error)
                usb_autopm_put_interface(wacom->intf);
}

/*
 * Calculate the resolution of the X or Y axis, given appropriate HID data.
 * This function is little more than hidinput_calc_abs_res stripped down.
 */
static int wacom_calc_hid_res(int logical_extents, int physical_extents,
                              unsigned char unit, unsigned char exponent)
{
        int prev, unit_exponent;

        /* Check if the extents are sane */
        if (logical_extents <= 0 || physical_extents <= 0)
                return 0;

        /* Get signed value of nybble-sized twos-compliment exponent */
        unit_exponent = exponent;
        if (unit_exponent > 7)
                unit_exponent -= 16;

        /* Convert physical_extents to millimeters */
        if (unit == 0x11) {             /* If centimeters */
                unit_exponent += 1;
        } else if (unit == 0x13) {      /* If inches */
                prev = physical_extents;
                physical_extents *= 254;
                if (physical_extents < prev)
                        return 0;
                unit_exponent -= 1;
        } else {
                return 0;
        }

        /* Apply negative unit exponent */
        for (; unit_exponent < 0; unit_exponent++) {
                prev = logical_extents;
                logical_extents *= 10;
                if (logical_extents < prev)
                        return 0;
        }
        /* Apply positive unit exponent */
        for (; unit_exponent > 0; unit_exponent--) {
                prev = physical_extents;
                physical_extents *= 10;
                if (physical_extents < prev)
                        return 0;
        }

        /* Calculate resolution */
        return logical_extents / physical_extents;
}

/*
 * The physical dimension specified by the HID descriptor is likely not in
 * the "100th of a mm" units expected by wacom_calculate_touch_res. This
 * function adjusts the value of [xy]_phy based on the unit and exponent
 * provided by the HID descriptor. If an error occurs durring conversion
 * (e.g. from the unit being left unspecified) [xy]_phy is not modified.
 */
static void wacom_fix_phy_from_hid(struct wacom_features *features)
{
        int xres = wacom_calc_hid_res(features->x_max, features->x_phy,
                                        features->unit, features->unitExpo);
        int yres = wacom_calc_hid_res(features->y_max, features->y_phy,
                                        features->unit, features->unitExpo);

        if (xres > 0 && yres > 0) {
                features->x_phy = (100 * features->x_max) / xres;
                features->y_phy = (100 * features->y_max) / yres;
        }
}

/*
 * Static values for max X/Y and resolution of Pen interface is stored in
 * features. This mean physical size of active area can be computed.
 * This is useful to do when Pen and Touch have same active area of tablet.
 * This means for Touch device, we only need to find max X/Y value and we
 * have enough information to compute resolution of touch.
 */
static void wacom_set_phy_from_res(struct wacom_features *features)
{
        features->x_phy = (features->x_max * 100) / features->x_resolution;
        features->y_phy = (features->y_max * 100) / features->y_resolution;
}

static int wacom_parse_logical_collection(unsigned char *report,
                                          struct wacom_features *features)
{
        int length = 0;

        if (features->type == BAMBOO_PT) {

                /* Logical collection is only used by 3rd gen Bamboo Touch */
                features->pktlen = WACOM_PKGLEN_BBTOUCH3;
                features->device_type = BTN_TOOL_FINGER;

                wacom_set_phy_from_res(features);

                features->x_max = features->y_max =
                        get_unaligned_le16(&report[10]);

                length = 11;
        }
        return length;
}

static void wacom_retrieve_report_data(struct usb_interface *intf,
                                       struct wacom_features *features)
{
        int result = 0;
        unsigned char *rep_data;

        rep_data = kmalloc(2, GFP_KERNEL);
        if (rep_data) {

                rep_data[0] = 12;
                result = wacom_get_report(intf, WAC_HID_FEATURE_REPORT,
                                          rep_data[0], rep_data, 2,
                                          WAC_MSG_RETRIES);

                if (result >= 0 && rep_data[1] > 2)
                        features->touch_max = rep_data[1];

                kfree(rep_data);
        }
}

/*
 * Interface Descriptor of wacom devices can be incomplete and
 * inconsistent so wacom_features table is used to store stylus
 * device's packet lengths, various maximum values, and tablet
 * resolution based on product ID's.
 *
 * For devices that contain 2 interfaces, wacom_features table is
 * inaccurate for the touch interface.  Since the Interface Descriptor
 * for touch interfaces has pretty complete data, this function exists
 * to query tablet for this missing information instead of hard coding in
 * an additional table.
 *
 * A typical Interface Descriptor for a stylus will contain a
 * boot mouse application collection that is not of interest and this
 * function will ignore it.
 *
 * It also contains a digitizer application collection that also is not
 * of interest since any information it contains would be duplicate
 * of what is in wacom_features. Usually it defines a report of an array
 * of bytes that could be used as max length of the stylus packet returned.
 * If it happens to define a Digitizer-Stylus Physical Collection then
 * the X and Y logical values contain valid data but it is ignored.
 *
 * A typical Interface Descriptor for a touch interface will contain a
 * Digitizer-Finger Physical Collection which will define both logical
 * X/Y maximum as well as the physical size of tablet. Since touch
 * interfaces haven't supported pressure or distance, this is enough
 * information to override invalid values in the wacom_features table.
 *
 * 3rd gen Bamboo Touch no longer define a Digitizer-Finger Pysical
 * Collection. Instead they define a Logical Collection with a single
 * Logical Maximum for both X and Y.
 *
 * Intuos5 touch interface does not contain useful data. We deal with
 * this after returning from this function.
 */
static int wacom_parse_hid(struct usb_interface *intf,
                           struct hid_descriptor *hid_desc,
                           struct wacom_features *features)
{
        struct usb_device *dev = interface_to_usbdev(intf);
        char limit = 0;
        /* result has to be defined as int for some devices */
        int result = 0;
        int i = 0, usage = WCM_UNDEFINED, finger = 0, pen = 0;
        unsigned char *report;

        report = kzalloc(hid_desc->wDescriptorLength, GFP_KERNEL);
        if (!report)
                return -ENOMEM;

        /* retrive report descriptors */
        do {
                result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
                        USB_REQ_GET_DESCRIPTOR,
                        USB_RECIP_INTERFACE | USB_DIR_IN,
                        HID_DEVICET_REPORT << 8,
                        intf->altsetting[0].desc.bInterfaceNumber, /* interface */
                        report,
                        hid_desc->wDescriptorLength,
                        5000); /* 5 secs */
        } while (result < 0 && limit++ < WAC_MSG_RETRIES);

        /* No need to parse the Descriptor. It isn't an error though */
        if (result < 0)
                goto out;

        for (i = 0; i < hid_desc->wDescriptorLength; i++) {

                switch (report[i]) {
                case HID_USAGE_PAGE:
                        switch (report[i + 1]) {
                        case HID_USAGE_PAGE_DIGITIZER:
                                usage = WCM_DIGITIZER;
                                i++;
                                break;

                        case HID_USAGE_PAGE_DESKTOP:
                                usage = WCM_DESKTOP;
                                i++;
                                break;
                        }
                        break;

                case HID_USAGE:
                        switch (report[i + 1]) {
                        case HID_USAGE_X:
                                if (usage == WCM_DESKTOP) {
                                        if (finger) {
                                                features->device_type = BTN_TOOL_FINGER;

                                                switch (features->type) {
                                                case TABLETPC2FG:
                                                        features->pktlen = WACOM_PKGLEN_TPC2FG;
                                                        break;

                                                case MTSCREEN:
                                                case WACOM_24HDT:
                                                        features->pktlen = WACOM_PKGLEN_MTOUCH;
                                                        break;

                                                case MTTPC:
                                                        features->pktlen = WACOM_PKGLEN_MTTPC;
                                                        break;

                                                case BAMBOO_PT:
                                                        features->pktlen = WACOM_PKGLEN_BBTOUCH;
                                                        break;

                                                default:
                                                        features->pktlen = WACOM_PKGLEN_GRAPHIRE;
                                                        break;
                                                }

                                                switch (features->type) {
                                                case BAMBOO_PT:
                                                        features->x_phy =
                                                                get_unaligned_le16(&report[i + 5]);
                                                        features->x_max =
                                                                get_unaligned_le16(&report[i + 8]);
                                                        i += 15;
                                                        break;

                                                case WACOM_24HDT:
                                                        features->x_max =
                                                                get_unaligned_le16(&report[i + 3]);
                                                        features->x_phy =
                                                                get_unaligned_le16(&report[i + 8]);
                                                        features->unit = report[i - 1];
                                                        features->unitExpo = report[i - 3];
                                                        i += 12;
                                                        break;

                                                default:
                                                        features->x_max =
                                                                get_unaligned_le16(&report[i + 3]);
                                                        features->x_phy =
                                                                get_unaligned_le16(&report[i + 6]);
                                                        features->unit = report[i + 9];
                                                        features->unitExpo = report[i + 11];
                                                        i += 12;
                                                        break;
                                                }
                                        } else if (pen) {
                                                /* penabled only accepts exact bytes of data */
                                                if (features->type >= TABLETPC)
                                                        features->pktlen = WACOM_PKGLEN_GRAPHIRE;
                                                features->device_type = BTN_TOOL_PEN;
                                                features->x_max =
                                                        get_unaligned_le16(&report[i + 3]);
                                                i += 4;
                                        }
                                }
                                break;

                        case HID_USAGE_Y:
                                if (usage == WCM_DESKTOP) {
                                        if (finger) {
                                                switch (features->type) {
                                                case TABLETPC2FG:
                                                case MTSCREEN:
                                                case MTTPC:
                                                        features->y_max =
                                                                get_unaligned_le16(&report[i + 3]);
                                                        features->y_phy =
                                                                get_unaligned_le16(&report[i + 6]);
                                                        i += 7;
                                                        break;

                                                case WACOM_24HDT:
                                                        features->y_max =
                                                                get_unaligned_le16(&report[i + 3]);
                                                        features->y_phy =
                                                                get_unaligned_le16(&report[i - 2]);
                                                        i += 7;
                                                        break;

                                                case BAMBOO_PT:
                                                        features->y_phy =
                                                                get_unaligned_le16(&report[i + 3]);
                                                        features->y_max =
                                                                get_unaligned_le16(&report[i + 6]);
                                                        i += 12;
                                                        break;

                                                default:
                                                        features->y_max =
                                                                features->x_max;
                                                        features->y_phy =
                                                                get_unaligned_le16(&report[i + 3]);
                                                        i += 4;
                                                        break;
                                                }
                                        } else if (pen) {
                                                features->y_max =
                                                        get_unaligned_le16(&report[i + 3]);
                                                i += 4;
                                        }
                                }
                                break;

                        case HID_USAGE_FINGER:
                                finger = 1;
                                i++;
                                break;

                        /*
                         * Requiring Stylus Usage will ignore boot mouse
                         * X/Y values and some cases of invalid Digitizer X/Y
                         * values commonly reported.
                         */
                        case HID_USAGE_STYLUS:
                                pen = 1;
                                i++;
                                break;

                        case HID_USAGE_CONTACTMAX:
                                /* leave touch_max as is if predefined */
                                if (!features->touch_max)
                                        wacom_retrieve_report_data(intf, features);
                                i++;
                                break;
                        }
                        break;

                case HID_COLLECTION_END:
                        /* reset UsagePage and Finger */
                        finger = usage = 0;
                        break;

                case HID_COLLECTION:
                        i++;
                        switch (report[i]) {
                        case HID_COLLECTION_LOGICAL:
                                i += wacom_parse_logical_collection(&report[i],
                                                                    features);
                                break;
                        }
                        break;
                }
        }

 out:
        result = 0;
        kfree(report);
        return result;
}

static int wacom_set_device_mode(struct usb_interface *intf, int report_id, int length, int mode)
{
        unsigned char *rep_data;
        int error = -ENOMEM, limit = 0;

        rep_data = kzalloc(length, GFP_KERNEL);
        if (!rep_data)
                return error;

        do {
                rep_data[0] = report_id;
                rep_data[1] = mode;

                error = wacom_set_report(intf, WAC_HID_FEATURE_REPORT,
                                         report_id, rep_data, length, 1);
                if (error >= 0)
                        error = wacom_get_report(intf, WAC_HID_FEATURE_REPORT,
                                                 report_id, rep_data, length, 1);
        } while ((error < 0 || rep_data[1] != mode) && limit++ < WAC_MSG_RETRIES);

        kfree(rep_data);

        return error < 0 ? error : 0;
}

/*
 * Switch the tablet into its most-capable mode. Wacom tablets are
 * typically configured to power-up in a mode which sends mouse-like
 * reports to the OS. To get absolute position, pressure data, etc.
 * from the tablet, it is necessary to switch the tablet out of this
 * mode and into one which sends the full range of tablet data.
 */
static int wacom_query_tablet_data(struct usb_interface *intf, struct wacom_features *features)
{
        if (features->device_type == BTN_TOOL_FINGER) {
                if (features->type > TABLETPC) {
                        /* MT Tablet PC touch */
                        return wacom_set_device_mode(intf, 3, 4, 4);
                }
                else if (features->type == WACOM_24HDT) {
                        return wacom_set_device_mode(intf, 18, 3, 2);
                }
        } else if (features->device_type == BTN_TOOL_PEN) {
                if (features->type <= BAMBOO_PT && features->type != WIRELESS) {
                        return wacom_set_device_mode(intf, 2, 2, 2);
                }
        }

        return 0;
}

static int wacom_retrieve_hid_descriptor(struct usb_interface *intf,
                                         struct wacom_features *features)
{
        int error = 0;
        struct usb_host_interface *interface = intf->cur_altsetting;
        struct hid_descriptor *hid_desc;

        /* default features */
        features->device_type = BTN_TOOL_PEN;
        features->x_fuzz = 4;
        features->y_fuzz = 4;
        features->pressure_fuzz = 0;
        features->distance_fuzz = 0;

        /*
         * The wireless device HID is basic and layout conflicts with
         * other tablets (monitor and touch interface can look like pen).
         * Skip the query for this type and modify defaults based on
         * interface number.
         */
        if (features->type == WIRELESS) {
                if (intf->cur_altsetting->desc.bInterfaceNumber == 0) {
                        features->device_type = 0;
                } else if (intf->cur_altsetting->desc.bInterfaceNumber == 2) {
                        features->device_type = BTN_TOOL_FINGER;
                        features->pktlen = WACOM_PKGLEN_BBTOUCH3;
                }
        }

        /* only devices that support touch need to retrieve the info */
        if (features->type < BAMBOO_PT) {
                goto out;
        }

        error = usb_get_extra_descriptor(interface, HID_DEVICET_HID, &hid_desc);
        if (error) {
                error = usb_get_extra_descriptor(&interface->endpoint[0],
                                                 HID_DEVICET_REPORT, &hid_desc);
                if (error) {
                        dev_err(&intf->dev,
                                "can not retrieve extra class descriptor\n");
                        goto out;
                }
        }
        error = wacom_parse_hid(intf, hid_desc, features);
        if (error)
                goto out;
        wacom_fix_phy_from_hid(features);

 out:
        return error;
}

struct wacom_usbdev_data {
        struct list_head list;
        struct kref kref;
        struct usb_device *dev;
        struct wacom_shared shared;
};

static LIST_HEAD(wacom_udev_list);
static DEFINE_MUTEX(wacom_udev_list_lock);

static struct usb_device *wacom_get_sibling(struct usb_device *dev, int vendor, int product)
{
        int port1;
        struct usb_device *sibling;

        if (vendor == 0 && product == 0)
                return dev;

        if (dev->parent == NULL)
                return NULL;

        usb_hub_for_each_child(dev->parent, port1, sibling) {
                struct usb_device_descriptor *d;
                if (sibling == NULL)
                        continue;

                d = &sibling->descriptor;
                if (d->idVendor == vendor && d->idProduct == product)
                        return sibling;
        }

        return NULL;
}

static struct wacom_usbdev_data *wacom_get_usbdev_data(struct usb_device *dev)
{
        struct wacom_usbdev_data *data;

        list_for_each_entry(data, &wacom_udev_list, list) {
                if (data->dev == dev) {
                        kref_get(&data->kref);
                        return data;
                }
        }

        return NULL;
}

static int wacom_add_shared_data(struct wacom_wac *wacom,
                                 struct usb_device *dev)
{
        struct wacom_usbdev_data *data;
        int retval = 0;

        mutex_lock(&wacom_udev_list_lock);

        data = wacom_get_usbdev_data(dev);
        if (!data) {
                data = kzalloc(sizeof(struct wacom_usbdev_data), GFP_KERNEL);
                if (!data) {
                        retval = -ENOMEM;
                        goto out;
                }

                kref_init(&data->kref);
                data->dev = dev;
                list_add_tail(&data->list, &wacom_udev_list);
        }

        wacom->shared = &data->shared;

out:
        mutex_unlock(&wacom_udev_list_lock);
        return retval;
}

static void wacom_release_shared_data(struct kref *kref)
{
        struct wacom_usbdev_data *data =
                container_of(kref, struct wacom_usbdev_data, kref);

        mutex_lock(&wacom_udev_list_lock);
        list_del(&data->list);
        mutex_unlock(&wacom_udev_list_lock);

        kfree(data);
}

static void wacom_remove_shared_data(struct wacom_wac *wacom)
{
        struct wacom_usbdev_data *data;

        if (wacom->shared) {
                data = container_of(wacom->shared, struct wacom_usbdev_data, shared);
                kref_put(&data->kref, wacom_release_shared_data);
                wacom->shared = NULL;
        }
}

static int wacom_led_control(struct wacom *wacom)
{
        unsigned char *buf;
        int retval;

        buf = kzalloc(9, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        if (wacom->wacom_wac.features.type >= INTUOS5S &&
            wacom->wacom_wac.features.type <= INTUOS5L) {
                /*
                 * Touch Ring and crop mark LED luminance may take on
                 * one of four values:
                 *    0 = Low; 1 = Medium; 2 = High; 3 = Off
                 */
                int ring_led = wacom->led.select[0] & 0x03;
                int ring_lum = (((wacom->led.llv & 0x60) >> 5) - 1) & 0x03;
                int crop_lum = 0;

                buf[0] = WAC_CMD_LED_CONTROL;
                buf[1] = (crop_lum << 4) | (ring_lum << 2) | (ring_led);
        }
        else {
                int led = wacom->led.select[0] | 0x4;

                if (wacom->wacom_wac.features.type == WACOM_21UX2 ||
                    wacom->wacom_wac.features.type == WACOM_24HD)
                        led |= (wacom->led.select[1] << 4) | 0x40;

                buf[0] = WAC_CMD_LED_CONTROL;
                buf[1] = led;
                buf[2] = wacom->led.llv;
                buf[3] = wacom->led.hlv;
                buf[4] = wacom->led.img_lum;
        }

        retval = wacom_set_report(wacom->intf, 0x03, WAC_CMD_LED_CONTROL,
                                  buf, 9, WAC_CMD_RETRIES);
        kfree(buf);

        return retval;
}

static int wacom_led_putimage(struct wacom *wacom, int button_id, const void *img)
{
        unsigned char *buf;
        int i, retval;

        buf = kzalloc(259, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        /* Send 'start' command */
        buf[0] = WAC_CMD_ICON_START;
        buf[1] = 1;
        retval = wacom_set_report(wacom->intf, 0x03, WAC_CMD_ICON_START,
                                  buf, 2, WAC_CMD_RETRIES);
        if (retval < 0)
                goto out;

        buf[0] = WAC_CMD_ICON_XFER;
        buf[1] = button_id & 0x07;
        for (i = 0; i < 4; i++) {
                buf[2] = i;
                memcpy(buf + 3, img + i * 256, 256);

                retval = wacom_set_report(wacom->intf, 0x03, WAC_CMD_ICON_XFER,
                                          buf, 259, WAC_CMD_RETRIES);
                if (retval < 0)
                        break;
        }

        /* Send 'stop' */
        buf[0] = WAC_CMD_ICON_START;
        buf[1] = 0;
        wacom_set_report(wacom->intf, 0x03, WAC_CMD_ICON_START,
                         buf, 2, WAC_CMD_RETRIES);

out:
        kfree(buf);
        return retval;
}

static ssize_t wacom_led_select_store(struct device *dev, int set_id,
                                      const char *buf, size_t count)
{
        struct wacom *wacom = dev_get_drvdata(dev);
        unsigned int id;
        int err;

        err = kstrtouint(buf, 10, &id);
        if (err)
                return err;

        mutex_lock(&wacom->lock);

        wacom->led.select[set_id] = id & 0x3;
        err = wacom_led_control(wacom);

        mutex_unlock(&wacom->lock);

        return err < 0 ? err : count;
}

#define DEVICE_LED_SELECT_ATTR(SET_ID)                                  \
static ssize_t wacom_led##SET_ID##_select_store(struct device *dev,     \
        struct device_attribute *attr, const char *buf, size_t count)   \
{                                                                       \
        return wacom_led_select_store(dev, SET_ID, buf, count);         \
}                                                                       \
static ssize_t wacom_led##SET_ID##_select_show(struct device *dev,      \
        struct device_attribute *attr, char *buf)                       \
{                                                                       \
        struct wacom *wacom = dev_get_drvdata(dev);                     \
        return snprintf(buf, 2, "%d\n", wacom->led.select[SET_ID]);     \
}                                                                       \
static DEVICE_ATTR(status_led##SET_ID##_select, S_IWUSR | S_IRUSR,      \
                    wacom_led##SET_ID##_select_show,                    \
                    wacom_led##SET_ID##_select_store)

DEVICE_LED_SELECT_ATTR(0);
DEVICE_LED_SELECT_ATTR(1);

static ssize_t wacom_luminance_store(struct wacom *wacom, u8 *dest,
                                     const char *buf, size_t count)
{
        unsigned int value;
        int err;

        err = kstrtouint(buf, 10, &value);
        if (err)
                return err;

        mutex_lock(&wacom->lock);

        *dest = value & 0x7f;
        err = wacom_led_control(wacom);

        mutex_unlock(&wacom->lock);

        return err < 0 ? err : count;
}

#define DEVICE_LUMINANCE_ATTR(name, field)                              \
static ssize_t wacom_##name##_luminance_store(struct device *dev,       \
        struct device_attribute *attr, const char *buf, size_t count)   \
{                                                                       \
        struct wacom *wacom = dev_get_drvdata(dev);                     \
                                                                        \
        return wacom_luminance_store(wacom, &wacom->led.field,          \
                                     buf, count);                       \
}                                                                       \
static DEVICE_ATTR(name##_luminance, S_IWUSR,                           \
                   NULL, wacom_##name##_luminance_store)

DEVICE_LUMINANCE_ATTR(status0, llv);
DEVICE_LUMINANCE_ATTR(status1, hlv);
DEVICE_LUMINANCE_ATTR(buttons, img_lum);

static ssize_t wacom_button_image_store(struct device *dev, int button_id,
                                        const char *buf, size_t count)
{
        struct wacom *wacom = dev_get_drvdata(dev);
        int err;

        if (count != 1024)
                return -EINVAL;

        mutex_lock(&wacom->lock);

        err = wacom_led_putimage(wacom, button_id, buf);

        mutex_unlock(&wacom->lock);

        return err < 0 ? err : count;
}

#define DEVICE_BTNIMG_ATTR(BUTTON_ID)                                   \
static ssize_t wacom_btnimg##BUTTON_ID##_store(struct device *dev,      \
        struct device_attribute *attr, const char *buf, size_t count)   \
{                                                                       \
        return wacom_button_image_store(dev, BUTTON_ID, buf, count);    \
}                                                                       \
static DEVICE_ATTR(button##BUTTON_ID##_rawimg, S_IWUSR,                 \
                   NULL, wacom_btnimg##BUTTON_ID##_store)

DEVICE_BTNIMG_ATTR(0);
DEVICE_BTNIMG_ATTR(1);
DEVICE_BTNIMG_ATTR(2);
DEVICE_BTNIMG_ATTR(3);
DEVICE_BTNIMG_ATTR(4);
DEVICE_BTNIMG_ATTR(5);
DEVICE_BTNIMG_ATTR(6);
DEVICE_BTNIMG_ATTR(7);

static struct attribute *cintiq_led_attrs[] = {
        &dev_attr_status_led0_select.attr,
        &dev_attr_status_led1_select.attr,
        NULL
};

static struct attribute_group cintiq_led_attr_group = {
        .name = "wacom_led",
        .attrs = cintiq_led_attrs,
};

static struct attribute *intuos4_led_attrs[] = {
        &dev_attr_status0_luminance.attr,
        &dev_attr_status1_luminance.attr,
        &dev_attr_status_led0_select.attr,
        &dev_attr_buttons_luminance.attr,
        &dev_attr_button0_rawimg.attr,
        &dev_attr_button1_rawimg.attr,
        &dev_attr_button2_rawimg.attr,
        &dev_attr_button3_rawimg.attr,
        &dev_attr_button4_rawimg.attr,
        &dev_attr_button5_rawimg.attr,
        &dev_attr_button6_rawimg.attr,
        &dev_attr_button7_rawimg.attr,
        NULL
};

static struct attribute_group intuos4_led_attr_group = {
        .name = "wacom_led",
        .attrs = intuos4_led_attrs,
};

static struct attribute *intuos5_led_attrs[] = {
        &dev_attr_status0_luminance.attr,
        &dev_attr_status_led0_select.attr,
        NULL
};

static struct attribute_group intuos5_led_attr_group = {
        .name = "wacom_led",
        .attrs = intuos5_led_attrs,
};

static int wacom_initialize_leds(struct wacom *wacom)
{
        int error;

        /* Initialize default values */
        switch (wacom->wacom_wac.features.type) {
        case INTUOS4S:
        case INTUOS4:
        case INTUOS4L:
                wacom->led.select[0] = 0;
                wacom->led.select[1] = 0;
                wacom->led.llv = 10;

                wacom->led.hlv = 20;
                wacom->led.img_lum = 10;
                error = sysfs_create_group(&wacom->intf->dev.kobj,
                                           &intuos4_led_attr_group);
                break;

        case WACOM_24HD:
        case WACOM_21UX2:
                wacom->led.select[0] = 0;
                wacom->led.select[1] = 0;
                wacom->led.llv = 0;
                wacom->led.hlv = 0;
                wacom->led.img_lum = 0;

                error = sysfs_create_group(&wacom->intf->dev.kobj,
                                           &cintiq_led_attr_group);
                break;

        case INTUOS5S:
        case INTUOS5:
        case INTUOS5L:
                wacom->led.select[0] = 0;
                wacom->led.select[1] = 0;
                wacom->led.llv = 32;
                wacom->led.hlv = 0;
                wacom->led.img_lum = 0;

                error = sysfs_create_group(&wacom->intf->dev.kobj,
                                           &intuos5_led_attr_group);
                break;

        default:
                return 0;
        }

        if (error) {
                dev_err(&wacom->intf->dev,
                        "cannot create sysfs group err: %d\n", error);
                return error;
        }
        wacom_led_control(wacom);

        return 0;
}

static void wacom_destroy_leds(struct wacom *wacom)
{
        switch (wacom->wacom_wac.features.type) {
        case INTUOS4S:
        case INTUOS4:
        case INTUOS4L:
                sysfs_remove_group(&wacom->intf->dev.kobj,
                                   &intuos4_led_attr_group);
                break;

        case WACOM_24HD:
        case WACOM_21UX2:
                sysfs_remove_group(&wacom->intf->dev.kobj,
                                   &cintiq_led_attr_group);
                break;

        case INTUOS5S:
        case INTUOS5:
        case INTUOS5L:
                sysfs_remove_group(&wacom->intf->dev.kobj,
                                   &intuos5_led_attr_group);
                break;
        }
}

static enum power_supply_property wacom_battery_props[] = {
        POWER_SUPPLY_PROP_CAPACITY
};

static int wacom_battery_get_property(struct power_supply *psy,
                                      enum power_supply_property psp,
                                      union power_supply_propval *val)
{
        struct wacom *wacom = container_of(psy, struct wacom, battery);
        int ret = 0;

        switch (psp) {
                case POWER_SUPPLY_PROP_CAPACITY:
                        val->intval =
                                wacom->wacom_wac.battery_capacity * 100 / 31;
                        break;
                default:
                        ret = -EINVAL;
                        break;
        }

        return ret;
}

static int wacom_initialize_battery(struct wacom *wacom)
{
        int error = 0;

        if (wacom->wacom_wac.features.quirks & WACOM_QUIRK_MONITOR) {
                wacom->battery.properties = wacom_battery_props;
                wacom->battery.num_properties = ARRAY_SIZE(wacom_battery_props);
                wacom->battery.get_property = wacom_battery_get_property;
                wacom->battery.name = "wacom_battery";
                wacom->battery.type = POWER_SUPPLY_TYPE_BATTERY;
                wacom->battery.use_for_apm = 0;

                error = power_supply_register(&wacom->usbdev->dev,
                                              &wacom->battery);

                if (!error)
                        power_supply_powers(&wacom->battery,
                                            &wacom->usbdev->dev);
        }

        return error;
}

static void wacom_destroy_battery(struct wacom *wacom)
{
        if (wacom->wacom_wac.features.quirks & WACOM_QUIRK_MONITOR &&
            wacom->battery.dev) {
                power_supply_unregister(&wacom->battery);
                wacom->battery.dev = NULL;
        }
}

static int wacom_register_input(struct wacom *wacom)
{
        struct input_dev *input_dev;
        struct usb_interface *intf = wacom->intf;
        struct usb_device *dev = interface_to_usbdev(intf);
        struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
        int error;

        input_dev = input_allocate_device();
        if (!input_dev) {
                error = -ENOMEM;
                goto fail1;
        }

        input_dev->name = wacom_wac->name;
        input_dev->dev.parent = &intf->dev;
        input_dev->open = wacom_open;
        input_dev->close = wacom_close;
        usb_to_input_id(dev, &input_dev->id);
        input_set_drvdata(input_dev, wacom);

        wacom_wac->input = input_dev;
        error = wacom_setup_input_capabilities(input_dev, wacom_wac);
        if (error)
                goto fail1;

        error = input_register_device(input_dev);
        if (error)
                goto fail2;

        return 0;

fail2:
        input_free_device(input_dev);
        wacom_wac->input = NULL;
fail1:
        return error;
}

static void wacom_wireless_work(struct work_struct *work)
{
        struct wacom *wacom = container_of(work, struct wacom, work);
        struct usb_device *usbdev = wacom->usbdev;
        struct wacom_wac *wacom_wac = &wacom->wacom_wac;
        struct wacom *wacom1, *wacom2;
        struct wacom_wac *wacom_wac1, *wacom_wac2;
        int error;

        /*
         * Regardless if this is a disconnect or a new tablet,
         * remove any existing input and battery devices.
         */

        wacom_destroy_battery(wacom);

        /* Stylus interface */
        wacom1 = usb_get_intfdata(usbdev->config->interface[1]);
        wacom_wac1 = &(wacom1->wacom_wac);
        if (wacom_wac1->input)
                input_unregister_device(wacom_wac1->input);
        wacom_wac1->input = NULL;

        /* Touch interface */
        wacom2 = usb_get_intfdata(usbdev->config->interface[2]);
        wacom_wac2 = &(wacom2->wacom_wac);
        if (wacom_wac2->input)
                input_unregister_device(wacom_wac2->input);
        wacom_wac2->input = NULL;

        if (wacom_wac->pid == 0) {
                dev_info(&wacom->intf->dev, "wireless tablet disconnected\n");
        } else {
                const struct usb_device_id *id = wacom_ids;

                dev_info(&wacom->intf->dev,
                         "wireless tablet connected with PID %x\n",
                         wacom_wac->pid);

                while (id->match_flags) {
                        if (id->idVendor == USB_VENDOR_ID_WACOM &&
                            id->idProduct == wacom_wac->pid)
                                break;
                        id++;
                }

                if (!id->match_flags) {
                        dev_info(&wacom->intf->dev,
                                 "ignoring unknown PID.\n");
                        return;
                }

                /* Stylus interface */
                wacom_wac1->features =
                        *((struct wacom_features *)id->driver_info);
                wacom_wac1->features.device_type = BTN_TOOL_PEN;
                error = wacom_register_input(wacom1);
                if (error)
                        goto fail1;

                /* Touch interface */
                wacom_wac2->features =
                        *((struct wacom_features *)id->driver_info);
                wacom_wac2->features.pktlen = WACOM_PKGLEN_BBTOUCH3;
                wacom_wac2->features.device_type = BTN_TOOL_FINGER;
                wacom_set_phy_from_res(&wacom_wac2->features);
                wacom_wac2->features.x_max = wacom_wac2->features.y_max = 4096;
                error = wacom_register_input(wacom2);
                if (error)
                        goto fail2;

                error = wacom_initialize_battery(wacom);
                if (error)
                        goto fail3;
        }

        return;

fail3:
        input_unregister_device(wacom_wac2->input);
        wacom_wac2->input = NULL;
fail2:
        input_unregister_device(wacom_wac1->input);
        wacom_wac1->input = NULL;
fail1:
        return;
}

static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
        struct usb_device *dev = interface_to_usbdev(intf);
        struct usb_endpoint_descriptor *endpoint;
        struct wacom *wacom;
        struct wacom_wac *wacom_wac;
        struct wacom_features *features;
        int error;

        if (!id->driver_info)
                return -EINVAL;

        wacom = kzalloc(sizeof(struct wacom), GFP_KERNEL);
        if (!wacom)
                return -ENOMEM;

        wacom_wac = &wacom->wacom_wac;
        wacom_wac->features = *((struct wacom_features *)id->driver_info);
        features = &wacom_wac->features;
        if (features->pktlen > WACOM_PKGLEN_MAX) {
                error = -EINVAL;
                goto fail1;
        }

        wacom_wac->data = usb_alloc_coherent(dev, WACOM_PKGLEN_MAX,
                                             GFP_KERNEL, &wacom->data_dma);
        if (!wacom_wac->data) {
                error = -ENOMEM;
                goto fail1;
        }

        wacom->irq = usb_alloc_urb(0, GFP_KERNEL);
        if (!wacom->irq) {
                error = -ENOMEM;
                goto fail2;
        }

        wacom->usbdev = dev;
        wacom->intf = intf;
        mutex_init(&wacom->lock);
        INIT_WORK(&wacom->work, wacom_wireless_work);
        usb_make_path(dev, wacom->phys, sizeof(wacom->phys));
        strlcat(wacom->phys, "/input0", sizeof(wacom->phys));

        endpoint = &intf->cur_altsetting->endpoint[0].desc;

        /* Retrieve the physical and logical size for touch devices */
        error = wacom_retrieve_hid_descriptor(intf, features);
        if (error)
                goto fail3;

        /*
         * Intuos5 has no useful data about its touch interface in its
         * HID descriptor. If this is the touch interface (wMaxPacketSize
         * of WACOM_PKGLEN_BBTOUCH3), override the table values.
         */
        if (features->type >= INTUOS5S && features->type <= INTUOS5L) {
                if (endpoint->wMaxPacketSize == WACOM_PKGLEN_BBTOUCH3) {
                        features->device_type = BTN_TOOL_FINGER;
                        features->pktlen = WACOM_PKGLEN_BBTOUCH3;

                        wacom_set_phy_from_res(features);

                        features->x_max = 4096;
                        features->y_max = 4096;
                } else {
                        features->device_type = BTN_TOOL_PEN;
                }
        }

        wacom_setup_device_quirks(features);

        strlcpy(wacom_wac->name, features->name, sizeof(wacom_wac->name));

        if (features->quirks & WACOM_QUIRK_MULTI_INPUT) {
                struct usb_device *other_dev;

                /* Append the device type to the name */
                strlcat(wacom_wac->name,
                        features->device_type == BTN_TOOL_PEN ?
                                " Pen" : " Finger",
                        sizeof(wacom_wac->name));


                other_dev = wacom_get_sibling(dev, features->oVid, features->oPid);
                if (other_dev == NULL || wacom_get_usbdev_data(other_dev) == NULL)
                        other_dev = dev;
                error = wacom_add_shared_data(wacom_wac, other_dev);
                if (error)
                        goto fail3;
        }

        usb_fill_int_urb(wacom->irq, dev,
                         usb_rcvintpipe(dev, endpoint->bEndpointAddress),
                         wacom_wac->data, features->pktlen,
                         wacom_sys_irq, wacom, endpoint->bInterval);
        wacom->irq->transfer_dma = wacom->data_dma;
        wacom->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

        error = wacom_initialize_leds(wacom);
        if (error)
                goto fail4;

        if (!(features->quirks & WACOM_QUIRK_NO_INPUT)) {
                error = wacom_register_input(wacom);
                if (error)
                        goto fail5;
        }

        /* Note that if query fails it is not a hard failure */
        wacom_query_tablet_data(intf, features);

        usb_set_intfdata(intf, wacom);

        if (features->quirks & WACOM_QUIRK_MONITOR) {
                if (usb_submit_urb(wacom->irq, GFP_KERNEL))
                        goto fail5;
        }

        return 0;

 fail5: wacom_destroy_leds(wacom);
 fail4: wacom_remove_shared_data(wacom_wac);
 fail3: usb_free_urb(wacom->irq);
 fail2: usb_free_coherent(dev, WACOM_PKGLEN_MAX, wacom_wac->data, wacom->data_dma);
 fail1: kfree(wacom);
        return error;
}

static void wacom_disconnect(struct usb_interface *intf)
{
        struct wacom *wacom = usb_get_intfdata(intf);

        usb_set_intfdata(intf, NULL);

        usb_kill_urb(wacom->irq);
        cancel_work_sync(&wacom->work);
        if (wacom->wacom_wac.input)
                input_unregister_device(wacom->wacom_wac.input);
        wacom_destroy_battery(wacom);
        wacom_destroy_leds(wacom);
        usb_free_urb(wacom->irq);
        usb_free_coherent(interface_to_usbdev(intf), WACOM_PKGLEN_MAX,
                        wacom->wacom_wac.data, wacom->data_dma);
        wacom_remove_shared_data(&wacom->wacom_wac);
        kfree(wacom);
}

static int wacom_suspend(struct usb_interface *intf, pm_message_t message)
{
        struct wacom *wacom = usb_get_intfdata(intf);

        mutex_lock(&wacom->lock);
        usb_kill_urb(wacom->irq);
        mutex_unlock(&wacom->lock);

        return 0;
}

static int wacom_resume(struct usb_interface *intf)
{
        struct wacom *wacom = usb_get_intfdata(intf);
        struct wacom_features *features = &wacom->wacom_wac.features;
        int rv = 0;

        mutex_lock(&wacom->lock);

        /* switch to wacom mode first */
        wacom_query_tablet_data(intf, features);
        wacom_led_control(wacom);

        if ((wacom->open || features->quirks & WACOM_QUIRK_MONITOR)
             && usb_submit_urb(wacom->irq, GFP_NOIO) < 0)
                rv = -EIO;

        mutex_unlock(&wacom->lock);

        return rv;
}

static int wacom_reset_resume(struct usb_interface *intf)
{
        return wacom_resume(intf);
}

static struct usb_driver wacom_driver = {
        .name =         "wacom",
        .id_table =     wacom_ids,
        .probe =        wacom_probe,
        .disconnect =   wacom_disconnect,
        .suspend =      wacom_suspend,
        .resume =       wacom_resume,
        .reset_resume = wacom_reset_resume,
        .supports_autosuspend = 1,
};

module_usb_driver(wacom_driver);