root/drivers/hid/hid-picolcd_cir.c
// SPDX-License-Identifier: GPL-2.0-only
/***************************************************************************
 *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
 *                                                                         *
 *   Based on Logitech G13 driver (v0.4)                                   *
 *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
 *                                                                         *
 ***************************************************************************/

#include <linux/hid.h>
#include <linux/hid-debug.h>
#include <linux/input.h>
#include "hid-ids.h"

#include <linux/fb.h>
#include <linux/vmalloc.h>
#include <linux/backlight.h>
#include <linux/lcd.h>

#include <linux/leds.h>

#include <linux/seq_file.h>
#include <linux/debugfs.h>

#include <linux/completion.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <media/rc-core.h>

#include "hid-picolcd.h"


int picolcd_raw_cir(struct picolcd_data *data,
                struct hid_report *report, u8 *raw_data, int size)
{
        unsigned long flags;
        int i, w, sz;
        struct ir_raw_event rawir = {};

        /* ignore if rc_dev is NULL or status is shunned */
        spin_lock_irqsave(&data->lock, flags);
        if (!data->rc_dev || (data->status & PICOLCD_CIR_SHUN)) {
                spin_unlock_irqrestore(&data->lock, flags);
                return 1;
        }
        spin_unlock_irqrestore(&data->lock, flags);

        /* PicoLCD USB packets contain 16-bit intervals in network order,
         * with value negated for pulse. Intervals are in microseconds.
         *
         * Note: some userspace LIRC code for PicoLCD says negated values
         * for space - is it a matter of IR chip? (pulse for my TSOP2236)
         *
         * In addition, the first interval seems to be around 15000 + base
         * interval for non-first report of IR data - thus the quirk below
         * to get RC_CODE to understand Sony and JVC remotes I have at hand
         */
        sz = size > 0 ? min((int)raw_data[0], size-1) : 0;
        for (i = 0; i+1 < sz; i += 2) {
                w = (raw_data[i] << 8) | (raw_data[i+1]);
                rawir.pulse = !!(w & 0x8000);
                rawir.duration = rawir.pulse ? (65536 - w) : w;
                /* Quirk!! - see above */
                if (i == 0 && rawir.duration > 15000)
                        rawir.duration -= 15000;
                ir_raw_event_store(data->rc_dev, &rawir);
        }
        ir_raw_event_handle(data->rc_dev);

        return 1;
}

static int picolcd_cir_open(struct rc_dev *dev)
{
        struct picolcd_data *data = dev->priv;
        unsigned long flags;

        spin_lock_irqsave(&data->lock, flags);
        data->status &= ~PICOLCD_CIR_SHUN;
        spin_unlock_irqrestore(&data->lock, flags);
        return 0;
}

static void picolcd_cir_close(struct rc_dev *dev)
{
        struct picolcd_data *data = dev->priv;
        unsigned long flags;

        spin_lock_irqsave(&data->lock, flags);
        data->status |= PICOLCD_CIR_SHUN;
        spin_unlock_irqrestore(&data->lock, flags);
}

/* initialize CIR input device */
int picolcd_init_cir(struct picolcd_data *data, struct hid_report *report)
{
        struct rc_dev *rdev;
        int ret = 0;

        rdev = rc_allocate_device(RC_DRIVER_IR_RAW);
        if (!rdev)
                return -ENOMEM;

        rdev->priv             = data;
        rdev->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
        rdev->open             = picolcd_cir_open;
        rdev->close            = picolcd_cir_close;
        rdev->device_name      = data->hdev->name;
        rdev->input_phys       = data->hdev->phys;
        rdev->input_id.bustype = data->hdev->bus;
        rdev->input_id.vendor  = data->hdev->vendor;
        rdev->input_id.product = data->hdev->product;
        rdev->input_id.version = data->hdev->version;
        rdev->dev.parent       = &data->hdev->dev;
        rdev->driver_name      = PICOLCD_NAME;
        rdev->map_name         = RC_MAP_RC6_MCE;
        rdev->timeout          = MS_TO_US(100);
        rdev->rx_resolution    = 1;

        ret = rc_register_device(rdev);
        if (ret)
                goto err;
        data->rc_dev = rdev;
        return 0;

err:
        rc_free_device(rdev);
        return ret;
}

void picolcd_exit_cir(struct picolcd_data *data)
{
        struct rc_dev *rdev = data->rc_dev;

        data->rc_dev = NULL;
        rc_unregister_device(rdev);
}