/*
 *
 * 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.
 *
 */

#include <asm/unaligned.h>
#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_proto *protocol,
			       u32 *scancode, u8 *ptoggle, int size)
{
	unsigned char buf[6];
	int start, range, toggle, dev, code, ircode, vendor;

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

	if (buf[0] & 0x80) {
		int offset = (size == 6) ? 3 : 0;

		/* 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_PROTO_RC5;
		*scancode = RC_SCANCODE_RC5(dev, code);
		*ptoggle = toggle;

		return 1;
	} else if (size == 6 && (buf[0] & 0x40)) {
		code = buf[4];
		dev = buf[3];
		vendor = get_unaligned_be16(buf + 1);

		if (vendor == 0x800f) {
			*ptoggle = (dev & 0x80) != 0;
			*protocol = RC_PROTO_RC6_MCE;
			dev &= 0x7f;
			dprintk(1, "ir hauppauge (rc6-mce): t%d vendor=%d dev=%d code=%d\n",
						*ptoggle, vendor, dev, code);
		} else {
			*ptoggle = 0;
			*protocol = RC_PROTO_RC6_6A_32;
			dprintk(1, "ir hauppauge (rc6-6a-32): vendor=%d dev=%d code=%d\n",
							vendor, dev, code);
		}

		*scancode = RC_SCANCODE_RC6_6A(vendor, dev, code);

		return 1;
	}

	return 0;
}

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

static int get_key_haup_xvr(struct IR_i2c *ir, enum rc_proto *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);
}

static int get_key_pixelview(struct IR_i2c *ir, enum rc_proto *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_PROTO_OTHER;
	*scancode = b;
	*toggle = 0;
	return 1;
}

static int get_key_fusionhdtv(struct IR_i2c *ir, enum rc_proto *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_PROTO_UNKNOWN;
	*scancode = buf[2];
	*toggle = 0;
	return 1;
}

static int get_key_knc1(struct IR_i2c *ir, enum rc_proto *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_PROTO_UNKNOWN;
	*scancode = b;
	*toggle = 0;
	return 1;
}

static int get_key_avermedia_cardbus(struct IR_i2c *ir, enum rc_proto *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_PROTO_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_proto 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_proto = RC_PROTO_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_proto    = RC_PROTO_BIT_OTHER;
		ir_codes    = RC_MAP_EMPTY;
		break;
	case 0x18:
	case 0x1f:
	case 0x1a:
		name        = "Hauppauge";
		ir->get_key = get_key_haup;
		rc_proto    = RC_PROTO_BIT_RC5;
		ir_codes    = RC_MAP_HAUPPAUGE;
		break;
	case 0x30:
		name        = "KNC One";
		ir->get_key = get_key_knc1;
		rc_proto    = RC_PROTO_BIT_OTHER;
		ir_codes    = RC_MAP_EMPTY;
		break;
	case 0x6b:
		name        = "FusionHDTV";
		ir->get_key = get_key_fusionhdtv;
		rc_proto    = RC_PROTO_BIT_UNKNOWN;
		ir_codes    = RC_MAP_FUSIONHDTV_MCE;
		break;
	case 0x40:
		name        = "AVerMedia Cardbus remote";
		ir->get_key = get_key_avermedia_cardbus;
		rc_proto    = RC_PROTO_BIT_OTHER;
		ir_codes    = RC_MAP_AVERMEDIA_CARDBUS;
		break;
	case 0x41:
		name        = "AVerMedia EM78P153";
		ir->get_key = get_key_avermedia_cardbus;
		rc_proto    = RC_PROTO_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_proto    = RC_PROTO_BIT_RC5 | RC_PROTO_BIT_RC6_MCE |
							RC_PROTO_BIT_RC6_6A_32;
		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_proto = 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(RC_DRIVER_SCANCODE);
		if (!rc)
			return -ENOMEM;
	}
	ir->rc = rc;

	/* Make sure we are all setup before going on */
	if (!name || !ir->get_key || !rc_proto || !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->device_name	     = ir->name;

	/*
	 * Initialize the other fields of rc_dev
	 */
	rc->map_name       = ir->ir_codes;
	rc->allowed_protocols = rc_proto;
	rc->enabled_protocols = rc_proto;
	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");