/*
 *
 * keyboard input driver for i2c IR remote controls
 *
 * Copyright (c) 2000-2003 Gerd Knorr <kraxel@bytesex.org>
 * modified for PixelView (BT878P+W/FM) by
 *      Michal Kochanowicz <mkochano@pld.org.pl>
 *      Christoph Bartelmus <lirc@bartelmus.de>
 * modified for KNC ONE TV Station/Anubis Typhoon TView Tuner by
 *      Ulrich Mueller <ulrich.mueller42@web.de>
 * modified for em2820 based USB TV tuners by
 *      Markus Rechberger <mrechberger@gmail.com>
 * modified for DViCO Fusion HDTV 5 RT GOLD by
 *      Chaogui Zhang <czhang1974@gmail.com>
 * modified for MSI TV@nywhere Plus by
 *      Henry Wong <henry@stuffedcow.net>
 *      Mark Schultz <n9xmj@yahoo.com>
 *      Brian Rogers <brian_rogers@comcast.net>
 * modified for AVerMedia Cardbus by
 *      Oldrich Jedlicka <oldium.pro@seznam.cz>
 *
 *  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.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/workqueue.h>

#include <media/rc-core.h>
#include <media/i2c/ir-kbd-i2c.h>

/* ----------------------------------------------------------------------- */
/* insmod parameters                                                       */

static int debug;
module_param(debug, int, 0644);    /* debug level (0,1,2) */


#define MODULE_NAME "ir-kbd-i2c"
#define dprintk(level, fmt, arg...)     if (debug >= level) \
        printk(KERN_DEBUG MODULE_NAME ": " fmt , ## arg)

/* ----------------------------------------------------------------------- */

static int get_key_haup_common(struct IR_i2c *ir, enum rc_type *protocol,
                               u32 *scancode, u8 *ptoggle, int size, int offset)
{
        unsigned char buf[6];
        int start, range, toggle, dev, code, ircode;

        /* poll IR chip */
        if (size != i2c_master_recv(ir->c, buf, size))
                return -EIO;

        /* split rc5 data block ... */
        start  = (buf[offset] >> 7) &    1;
        range  = (buf[offset] >> 6) &    1;
        toggle = (buf[offset] >> 5) &    1;
        dev    =  buf[offset]       & 0x1f;
        code   = (buf[offset+1] >> 2) & 0x3f;

        /* rc5 has two start bits
         * the first bit must be one
         * the second bit defines the command range (1 = 0-63, 0 = 64 - 127)
         */
        if (!start)
                /* no key pressed */
                return 0;

        /* filter out invalid key presses */
        ircode = (start << 12) | (toggle << 11) | (dev << 6) | code;
        if ((ircode & 0x1fff) == 0x1fff)
                return 0;

        if (!range)
                code += 64;

        dprintk(1,"ir hauppauge (rc5): s%d r%d t%d dev=%d code=%d\n",
                start, range, toggle, dev, code);

        *protocol = RC_TYPE_RC5;
        *scancode = RC_SCANCODE_RC5(dev, code);
        *ptoggle = toggle;
        return 1;
}

static int get_key_haup(struct IR_i2c *ir, enum rc_type *protocol,
                        u32 *scancode, u8 *toggle)
{
        return get_key_haup_common (ir, protocol, scancode, toggle, 3, 0);
}

static int get_key_haup_xvr(struct IR_i2c *ir, enum rc_type *protocol,
                            u32 *scancode, u8 *toggle)
{
        int ret;
        unsigned char buf[1] = { 0 };

        /*
         * This is the same apparent "are you ready?" poll command observed
         * watching Windows driver traffic and implemented in lirc_zilog. With
         * this added, we get far saner remote behavior with z8 chips on usb
         * connected devices, even with the default polling interval of 100ms.
         */
        ret = i2c_master_send(ir->c, buf, 1);
        if (ret != 1)
                return (ret < 0) ? ret : -EINVAL;

        return get_key_haup_common(ir, protocol, scancode, toggle, 6, 3);
}

static int get_key_pixelview(struct IR_i2c *ir, enum rc_type *protocol,
                             u32 *scancode, u8 *toggle)
{
        unsigned char b;

        /* poll IR chip */
        if (1 != i2c_master_recv(ir->c, &b, 1)) {
                dprintk(1,"read error\n");
                return -EIO;
        }

        *protocol = RC_TYPE_OTHER;
        *scancode = b;
        *toggle = 0;
        return 1;
}

static int get_key_fusionhdtv(struct IR_i2c *ir, enum rc_type *protocol,
                              u32 *scancode, u8 *toggle)
{
        unsigned char buf[4];

        /* poll IR chip */
        if (4 != i2c_master_recv(ir->c, buf, 4)) {
                dprintk(1,"read error\n");
                return -EIO;
        }

        if(buf[0] !=0 || buf[1] !=0 || buf[2] !=0 || buf[3] != 0)
                dprintk(2, "%s: 0x%2x 0x%2x 0x%2x 0x%2x\n", __func__,
                        buf[0], buf[1], buf[2], buf[3]);

        /* no key pressed or signal from other ir remote */
        if(buf[0] != 0x1 ||  buf[1] != 0xfe)
                return 0;

        *protocol = RC_TYPE_UNKNOWN;
        *scancode = buf[2];
        *toggle = 0;
        return 1;
}

static int get_key_knc1(struct IR_i2c *ir, enum rc_type *protocol,
                        u32 *scancode, u8 *toggle)
{
        unsigned char b;

        /* poll IR chip */
        if (1 != i2c_master_recv(ir->c, &b, 1)) {
                dprintk(1,"read error\n");
                return -EIO;
        }

        /* it seems that 0xFE indicates that a button is still hold
           down, while 0xff indicates that no button is hold
           down. 0xfe sequences are sometimes interrupted by 0xFF */

        dprintk(2,"key %02x\n", b);

        if (b == 0xff)
                return 0;

        if (b == 0xfe)
                /* keep old data */
                return 1;

        *protocol = RC_TYPE_UNKNOWN;
        *scancode = b;
        *toggle = 0;
        return 1;
}

static int get_key_avermedia_cardbus(struct IR_i2c *ir, enum rc_type *protocol,
                                     u32 *scancode, u8 *toggle)
{
        unsigned char subaddr, key, keygroup;
        struct i2c_msg msg[] = { { .addr = ir->c->addr, .flags = 0,
                                   .buf = &subaddr, .len = 1},
                                 { .addr = ir->c->addr, .flags = I2C_M_RD,
                                  .buf = &key, .len = 1} };
        subaddr = 0x0d;
        if (2 != i2c_transfer(ir->c->adapter, msg, 2)) {
                dprintk(1, "read error\n");
                return -EIO;
        }

        if (key == 0xff)
                return 0;

        subaddr = 0x0b;
        msg[1].buf = &keygroup;
        if (2 != i2c_transfer(ir->c->adapter, msg, 2)) {
                dprintk(1, "read error\n");
                return -EIO;
        }

        if (keygroup == 0xff)
                return 0;

        dprintk(1, "read key 0x%02x/0x%02x\n", key, keygroup);
        if (keygroup < 2 || keygroup > 4) {
                /* Only a warning */
                dprintk(1, "warning: invalid key group 0x%02x for key 0x%02x\n",
                                                                keygroup, key);
        }
        key |= (keygroup & 1) << 6;

        *protocol = RC_TYPE_UNKNOWN;
        *scancode = key;
        if (ir->c->addr == 0x41) /* AVerMedia EM78P153 */
                *scancode |= keygroup << 8;
        *toggle = 0;
        return 1;
}

/* ----------------------------------------------------------------------- */

static int ir_key_poll(struct IR_i2c *ir)
{
        enum rc_type protocol;
        u32 scancode;
        u8 toggle;
        int rc;

        dprintk(3, "%s\n", __func__);
        rc = ir->get_key(ir, &protocol, &scancode, &toggle);
        if (rc < 0) {
                dprintk(2,"error\n");
                return rc;
        }

        if (rc) {
                dprintk(1, "%s: proto = 0x%04x, scancode = 0x%08x\n",
                        __func__, protocol, scancode);
                rc_keydown(ir->rc, protocol, scancode, toggle);
        }
        return 0;
}

static void ir_work(struct work_struct *work)
{
        int rc;
        struct IR_i2c *ir = container_of(work, struct IR_i2c, work.work);

        rc = ir_key_poll(ir);
        if (rc == -ENODEV) {
                rc_unregister_device(ir->rc);
                ir->rc = NULL;
                return;
        }

        schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling_interval));
}

/* ----------------------------------------------------------------------- */

static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
        char *ir_codes = NULL;
        const char *name = NULL;
        u64 rc_type = RC_BIT_UNKNOWN;
        struct IR_i2c *ir;
        struct rc_dev *rc = NULL;
        struct i2c_adapter *adap = client->adapter;
        unsigned short addr = client->addr;
        int err;

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

        ir->c = client;
        ir->polling_interval = DEFAULT_POLLING_INTERVAL;
        i2c_set_clientdata(client, ir);

        switch(addr) {
        case 0x64:
                name        = "Pixelview";
                ir->get_key = get_key_pixelview;
                rc_type     = RC_BIT_OTHER;
                ir_codes    = RC_MAP_EMPTY;
                break;
        case 0x18:
        case 0x1f:
        case 0x1a:
                name        = "Hauppauge";
                ir->get_key = get_key_haup;
                rc_type     = RC_BIT_RC5;
                ir_codes    = RC_MAP_HAUPPAUGE;
                break;
        case 0x30:
                name        = "KNC One";
                ir->get_key = get_key_knc1;
                rc_type     = RC_BIT_OTHER;
                ir_codes    = RC_MAP_EMPTY;
                break;
        case 0x6b:
                name        = "FusionHDTV";
                ir->get_key = get_key_fusionhdtv;
                rc_type     = RC_BIT_UNKNOWN;
                ir_codes    = RC_MAP_FUSIONHDTV_MCE;
                break;
        case 0x40:
                name        = "AVerMedia Cardbus remote";
                ir->get_key = get_key_avermedia_cardbus;
                rc_type     = RC_BIT_OTHER;
                ir_codes    = RC_MAP_AVERMEDIA_CARDBUS;
                break;
        case 0x41:
                name        = "AVerMedia EM78P153";
                ir->get_key = get_key_avermedia_cardbus;
                rc_type     = RC_BIT_OTHER;
                /* RM-KV remote, seems to be same as RM-K6 */
                ir_codes    = RC_MAP_AVERMEDIA_M733A_RM_K6;
                break;
        case 0x71:
                name        = "Hauppauge/Zilog Z8";
                ir->get_key = get_key_haup_xvr;
                rc_type     = RC_BIT_RC5;
                ir_codes    = RC_MAP_HAUPPAUGE;
                break;
        }

        /* Let the caller override settings */
        if (client->dev.platform_data) {
                const struct IR_i2c_init_data *init_data =
                                                client->dev.platform_data;

                ir_codes = init_data->ir_codes;
                rc = init_data->rc_dev;

                name = init_data->name;
                if (init_data->type)
                        rc_type = init_data->type;

                if (init_data->polling_interval)
                        ir->polling_interval = init_data->polling_interval;

                switch (init_data->internal_get_key_func) {
                case IR_KBD_GET_KEY_CUSTOM:
                        /* The bridge driver provided us its own function */
                        ir->get_key = init_data->get_key;
                        break;
                case IR_KBD_GET_KEY_PIXELVIEW:
                        ir->get_key = get_key_pixelview;
                        break;
                case IR_KBD_GET_KEY_HAUP:
                        ir->get_key = get_key_haup;
                        break;
                case IR_KBD_GET_KEY_KNC1:
                        ir->get_key = get_key_knc1;
                        break;
                case IR_KBD_GET_KEY_FUSIONHDTV:
                        ir->get_key = get_key_fusionhdtv;
                        break;
                case IR_KBD_GET_KEY_HAUP_XVR:
                        ir->get_key = get_key_haup_xvr;
                        break;
                case IR_KBD_GET_KEY_AVERMEDIA_CARDBUS:
                        ir->get_key = get_key_avermedia_cardbus;
                        break;
                }
        }

        if (!rc) {
                /*
                 * If platform_data doesn't specify rc_dev, initialize it
                 * internally
                 */
                rc = rc_allocate_device();
                if (!rc)
                        return -ENOMEM;
        }
        ir->rc = rc;

        /* Make sure we are all setup before going on */
        if (!name || !ir->get_key || !rc_type || !ir_codes) {
                dprintk(1, ": Unsupported device at address 0x%02x\n",
                        addr);
                err = -ENODEV;
                goto err_out_free;
        }

        /* Sets name */
        snprintf(ir->name, sizeof(ir->name), "i2c IR (%s)", name);
        ir->ir_codes = ir_codes;

        snprintf(ir->phys, sizeof(ir->phys), "%s/%s/ir0",
                 dev_name(&adap->dev),
                 dev_name(&client->dev));

        /*
         * Initialize input_dev fields
         * It doesn't make sense to allow overriding them via platform_data
         */
        rc->input_id.bustype = BUS_I2C;
        rc->input_phys       = ir->phys;
        rc->input_name       = ir->name;

        /*
         * Initialize the other fields of rc_dev
         */
        rc->map_name       = ir->ir_codes;
        rc->allowed_protocols = rc_type;
        rc->enabled_protocols = rc_type;
        if (!rc->driver_name)
                rc->driver_name = MODULE_NAME;

        err = rc_register_device(rc);
        if (err)
                goto err_out_free;

        printk(MODULE_NAME ": %s detected at %s [%s]\n",
               ir->name, ir->phys, adap->name);

        /* start polling via eventd */
        INIT_DELAYED_WORK(&ir->work, ir_work);
        schedule_delayed_work(&ir->work, 0);

        return 0;

 err_out_free:
        /* Only frees rc if it were allocated internally */
        rc_free_device(rc);
        return err;
}

static int ir_remove(struct i2c_client *client)
{
        struct IR_i2c *ir = i2c_get_clientdata(client);

        /* kill outstanding polls */
        cancel_delayed_work_sync(&ir->work);

        /* unregister device */
        rc_unregister_device(ir->rc);

        /* free memory */
        return 0;
}

static const struct i2c_device_id ir_kbd_id[] = {
        /* Generic entry for any IR receiver */
        { "ir_video", 0 },
        /* IR device specific entries should be added here */
        { "ir_rx_z8f0811_haup", 0 },
        { "ir_rx_z8f0811_hdpvr", 0 },
        { }
};

static struct i2c_driver ir_kbd_driver = {
        .driver = {
                .name   = "ir-kbd-i2c",
        },
        .probe          = ir_probe,
        .remove         = ir_remove,
        .id_table       = ir_kbd_id,
};

module_i2c_driver(ir_kbd_driver);

/* ----------------------------------------------------------------------- */

MODULE_AUTHOR("Gerd Knorr, Michal Kochanowicz, Christoph Bartelmus, Ulrich Mueller");
MODULE_DESCRIPTION("input driver for i2c IR remote controls");
MODULE_LICENSE("GPL");