// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Plantronics USB HID Driver
 *
 *  Copyright (c) 2014 JD Cole <jd.cole@plantronics.com>
 *  Copyright (c) 2015-2018 Terry Junge <terry.junge@plantronics.com>
 */

#include "hid-ids.h"

#include <linux/hid.h>
#include <linux/module.h>
#include <linux/jiffies.h>

#define PLT_HID_1_0_PAGE        0xffa00000
#define PLT_HID_2_0_PAGE        0xffa20000

#define PLT_BASIC_TELEPHONY     0x0003
#define PLT_BASIC_EXCEPTION     0x0005

#define PLT_VOL_UP              0x00b1
#define PLT_VOL_DOWN            0x00b2
#define PLT_MIC_MUTE            0x00b5

#define PLT1_VOL_UP             (PLT_HID_1_0_PAGE | PLT_VOL_UP)
#define PLT1_VOL_DOWN           (PLT_HID_1_0_PAGE | PLT_VOL_DOWN)
#define PLT1_MIC_MUTE           (PLT_HID_1_0_PAGE | PLT_MIC_MUTE)
#define PLT2_VOL_UP             (PLT_HID_2_0_PAGE | PLT_VOL_UP)
#define PLT2_VOL_DOWN           (PLT_HID_2_0_PAGE | PLT_VOL_DOWN)
#define PLT2_MIC_MUTE           (PLT_HID_2_0_PAGE | PLT_MIC_MUTE)
#define HID_TELEPHONY_MUTE      (HID_UP_TELEPHONY | 0x2f)
#define HID_CONSUMER_MUTE       (HID_UP_CONSUMER | 0xe2)

#define PLT_DA60                0xda60
#define PLT_BT300_MIN           0x0413
#define PLT_BT300_MAX           0x0418

#define PLT_DOUBLE_KEY_TIMEOUT 5 /* ms */

struct plt_drv_data {
        unsigned long device_type;
        unsigned long last_key_ts;
        unsigned long double_key_to;
        __u16 last_key;
};

static int plantronics_input_mapping(struct hid_device *hdev,
                                     struct hid_input *hi,
                                     struct hid_field *field,
                                     struct hid_usage *usage,
                                     unsigned long **bit, int *max)
{
        unsigned short mapped_key;
        struct plt_drv_data *drv_data = hid_get_drvdata(hdev);
        unsigned long plt_type = drv_data->device_type;
        int allow_mute = usage->hid == HID_TELEPHONY_MUTE;
        int allow_consumer = field->application == HID_CP_CONSUMERCONTROL &&
                        (usage->hid & HID_USAGE_PAGE) == HID_UP_CONSUMER &&
                        usage->hid != HID_CONSUMER_MUTE;

        /* special case for PTT products */
        if (field->application == HID_GD_JOYSTICK)
                goto defaulted;

        /* non-standard types or multi-HID interfaces - plt_type is PID */
        if (!(plt_type & HID_USAGE_PAGE)) {
                switch (plt_type) {
                case PLT_DA60:
                        if (allow_consumer)
                                goto defaulted;
                        if (usage->hid == HID_CONSUMER_MUTE) {
                                mapped_key = KEY_MICMUTE;
                                goto mapped;
                        }
                        break;
                default:
                        if (allow_consumer || allow_mute)
                                goto defaulted;
                }
                goto ignored;
        }

        /* handle standard consumer control mapping */
        /* and standard telephony mic mute mapping */
        if (allow_consumer || allow_mute)
                goto defaulted;

        /* handle vendor unique types - plt_type is 0xffa0uuuu or 0xffa2uuuu */
        /* if not 'basic telephony compliant' - map vendor unique controls */
        if (!((plt_type & HID_USAGE) >= PLT_BASIC_TELEPHONY &&
              (plt_type & HID_USAGE) != PLT_BASIC_EXCEPTION) &&
              !((field->application ^ plt_type) & HID_USAGE_PAGE))
                switch (usage->hid) {
                case PLT1_VOL_UP:
                case PLT2_VOL_UP:
                        mapped_key = KEY_VOLUMEUP;
                        goto mapped;
                case PLT1_VOL_DOWN:
                case PLT2_VOL_DOWN:
                        mapped_key = KEY_VOLUMEDOWN;
                        goto mapped;
                case PLT1_MIC_MUTE:
                case PLT2_MIC_MUTE:
                        mapped_key = KEY_MICMUTE;
                        goto mapped;
                }

/*
 * Future mapping of call control or other usages,
 * if and when keys are defined would go here
 * otherwise, ignore everything else that was not mapped
 */

ignored:
        hid_dbg(hdev, "usage: %08x (appl: %08x) - ignored\n",
                usage->hid, field->application);
        return -1;

defaulted:
        hid_dbg(hdev, "usage: %08x (appl: %08x) - defaulted\n",
                usage->hid, field->application);
        return 0;

mapped:
        hid_map_usage_clear(hi, usage, bit, max, EV_KEY, mapped_key);
        hid_dbg(hdev, "usage: %08x (appl: %08x) - mapped to key %d\n",
                usage->hid, field->application, mapped_key);
        return 1;
}

static int plantronics_event(struct hid_device *hdev, struct hid_field *field,
                             struct hid_usage *usage, __s32 value)
{
        struct plt_drv_data *drv_data = hid_get_drvdata(hdev);
        unsigned long prev_tsto, cur_ts;
        __u16 prev_key, cur_key;

        /* Usages are filtered in plantronics_usages. */

        /* HZ too low for ms resolution - double key detection disabled */
        /* or it is a key release - handle key presses only. */
        if (!drv_data->double_key_to || !value)
                return 0;

        prev_tsto = drv_data->last_key_ts + drv_data->double_key_to;
        cur_ts = drv_data->last_key_ts = jiffies;
        prev_key = drv_data->last_key;
        cur_key = drv_data->last_key = usage->code;

        /* If the same key occurs in <= double_key_to -- ignore it */
        if (prev_key == cur_key && time_before_eq(cur_ts, prev_tsto)) {
                hid_dbg(hdev, "double key %d ignored\n", cur_key);
                return 1; /* Ignore the repeated key. */
        }
        return 0;
}

static unsigned long plantronics_device_type(struct hid_device *hdev)
{
        unsigned i, col_page;
        unsigned long plt_type = hdev->product;

        /* multi-HID interfaces? - plt_type is PID */
        if (plt_type >= PLT_BT300_MIN && plt_type <= PLT_BT300_MAX)
                goto exit;

        /* determine primary vendor page */
        for (i = 0; i < hdev->maxcollection; i++) {
                col_page = hdev->collection[i].usage & HID_USAGE_PAGE;
                if (col_page == PLT_HID_2_0_PAGE) {
                        plt_type = hdev->collection[i].usage;
                        break;
                }
                if (col_page == PLT_HID_1_0_PAGE)
                        plt_type = hdev->collection[i].usage;
        }

exit:
        hid_dbg(hdev, "plt_type decoded as: %08lx\n", plt_type);
        return plt_type;
}

static int plantronics_probe(struct hid_device *hdev,
                             const struct hid_device_id *id)
{
        struct plt_drv_data *drv_data;
        int ret;

        drv_data = devm_kzalloc(&hdev->dev, sizeof(*drv_data), GFP_KERNEL);
        if (!drv_data)
                return -ENOMEM;

        ret = hid_parse(hdev);
        if (ret) {
                hid_err(hdev, "parse failed\n");
                return ret;
        }

        drv_data->device_type = plantronics_device_type(hdev);
        drv_data->double_key_to = msecs_to_jiffies(PLT_DOUBLE_KEY_TIMEOUT);
        drv_data->last_key_ts = jiffies - drv_data->double_key_to;

        /* if HZ does not allow ms resolution - disable double key detection */
        if (drv_data->double_key_to < PLT_DOUBLE_KEY_TIMEOUT)
                drv_data->double_key_to = 0;

        hid_set_drvdata(hdev, drv_data);

        ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT |
                HID_CONNECT_HIDINPUT_FORCE | HID_CONNECT_HIDDEV_FORCE);
        if (ret)
                hid_err(hdev, "hw start failed\n");

        return ret;
}

static const struct hid_device_id plantronics_devices[] = {
        { HID_USB_DEVICE(USB_VENDOR_ID_PLANTRONICS, HID_ANY_ID) },
        { }
};
MODULE_DEVICE_TABLE(hid, plantronics_devices);

static const struct hid_usage_id plantronics_usages[] = {
        { HID_CP_VOLUMEUP, EV_KEY, HID_ANY_ID },
        { HID_CP_VOLUMEDOWN, EV_KEY, HID_ANY_ID },
        { HID_TELEPHONY_MUTE, EV_KEY, HID_ANY_ID },
        { HID_CONSUMER_MUTE, EV_KEY, HID_ANY_ID },
        { PLT2_VOL_UP, EV_KEY, HID_ANY_ID },
        { PLT2_VOL_DOWN, EV_KEY, HID_ANY_ID },
        { PLT2_MIC_MUTE, EV_KEY, HID_ANY_ID },
        { PLT1_VOL_UP, EV_KEY, HID_ANY_ID },
        { PLT1_VOL_DOWN, EV_KEY, HID_ANY_ID },
        { PLT1_MIC_MUTE, EV_KEY, HID_ANY_ID },
        { HID_TERMINATOR, HID_TERMINATOR, HID_TERMINATOR }
};

static struct hid_driver plantronics_driver = {
        .name = "plantronics",
        .id_table = plantronics_devices,
        .usage_table = plantronics_usages,
        .input_mapping = plantronics_input_mapping,
        .event = plantronics_event,
        .probe = plantronics_probe,
};
module_hid_driver(plantronics_driver);

MODULE_AUTHOR("JD Cole <jd.cole@plantronics.com>");
MODULE_AUTHOR("Terry Junge <terry.junge@plantronics.com>");
MODULE_DESCRIPTION("Plantronics USB HID Driver");
MODULE_LICENSE("GPL");