cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ir-kbd-i2c.c (23119B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      3 *
      4 * keyboard input driver for i2c IR remote controls
      5 *
      6 * Copyright (c) 2000-2003 Gerd Knorr <kraxel@bytesex.org>
      7 * modified for PixelView (BT878P+W/FM) by
      8 *      Michal Kochanowicz <mkochano@pld.org.pl>
      9 *      Christoph Bartelmus <lirc@bartelmus.de>
     10 * modified for KNC ONE TV Station/Anubis Typhoon TView Tuner by
     11 *      Ulrich Mueller <ulrich.mueller42@web.de>
     12 * modified for em2820 based USB TV tuners by
     13 *      Markus Rechberger <mrechberger@gmail.com>
     14 * modified for DViCO Fusion HDTV 5 RT GOLD by
     15 *      Chaogui Zhang <czhang1974@gmail.com>
     16 * modified for MSI TV@nywhere Plus by
     17 *      Henry Wong <henry@stuffedcow.net>
     18 *      Mark Schultz <n9xmj@yahoo.com>
     19 *      Brian Rogers <brian_rogers@comcast.net>
     20 * modified for AVerMedia Cardbus by
     21 *      Oldrich Jedlicka <oldium.pro@seznam.cz>
     22 * Zilog Transmitter portions/ideas were derived from GPLv2+ sources:
     23 *  - drivers/char/pctv_zilogir.[ch] from Hauppauge Broadway product
     24 *	Copyright 2011 Hauppauge Computer works
     25 *  - drivers/staging/media/lirc/lirc_zilog.c
     26 *	Copyright (c) 2000 Gerd Knorr <kraxel@goldbach.in-berlin.de>
     27 *	Michal Kochanowicz <mkochano@pld.org.pl>
     28 *	Christoph Bartelmus <lirc@bartelmus.de>
     29 *	Ulrich Mueller <ulrich.mueller42@web.de>
     30 *	Stefan Jahn <stefan@lkcc.org>
     31 *	Jerome Brock <jbrock@users.sourceforge.net>
     32 *	Thomas Reitmayr (treitmayr@yahoo.com)
     33 *	Mark Weaver <mark@npsl.co.uk>
     34 *	Jarod Wilson <jarod@redhat.com>
     35 *	Copyright (C) 2011 Andy Walls <awalls@md.metrocast.net>
     36 */
     37
     38#include <asm/unaligned.h>
     39#include <linux/module.h>
     40#include <linux/init.h>
     41#include <linux/kernel.h>
     42#include <linux/string.h>
     43#include <linux/timer.h>
     44#include <linux/delay.h>
     45#include <linux/errno.h>
     46#include <linux/slab.h>
     47#include <linux/i2c.h>
     48#include <linux/workqueue.h>
     49
     50#include <media/rc-core.h>
     51#include <media/i2c/ir-kbd-i2c.h>
     52
     53#define FLAG_TX		1
     54#define FLAG_HDPVR	2
     55
     56static bool enable_hdpvr;
     57module_param(enable_hdpvr, bool, 0644);
     58
     59static int get_key_haup_common(struct IR_i2c *ir, enum rc_proto *protocol,
     60			       u32 *scancode, u8 *ptoggle, int size)
     61{
     62	unsigned char buf[6];
     63	int start, range, toggle, dev, code, ircode, vendor;
     64
     65	/* poll IR chip */
     66	if (size != i2c_master_recv(ir->c, buf, size))
     67		return -EIO;
     68
     69	if (buf[0] & 0x80) {
     70		int offset = (size == 6) ? 3 : 0;
     71
     72		/* split rc5 data block ... */
     73		start  = (buf[offset] >> 7) &    1;
     74		range  = (buf[offset] >> 6) &    1;
     75		toggle = (buf[offset] >> 5) &    1;
     76		dev    =  buf[offset]       & 0x1f;
     77		code   = (buf[offset+1] >> 2) & 0x3f;
     78
     79		/* rc5 has two start bits
     80		 * the first bit must be one
     81		 * the second bit defines the command range:
     82		 * 1 = 0-63, 0 = 64 - 127
     83		 */
     84		if (!start)
     85			/* no key pressed */
     86			return 0;
     87
     88		/* filter out invalid key presses */
     89		ircode = (start << 12) | (toggle << 11) | (dev << 6) | code;
     90		if ((ircode & 0x1fff) == 0x1fff)
     91			return 0;
     92
     93		if (!range)
     94			code += 64;
     95
     96		dev_dbg(&ir->rc->dev,
     97			"ir hauppauge (rc5): s%d r%d t%d dev=%d code=%d\n",
     98			start, range, toggle, dev, code);
     99
    100		*protocol = RC_PROTO_RC5;
    101		*scancode = RC_SCANCODE_RC5(dev, code);
    102		*ptoggle = toggle;
    103
    104		return 1;
    105	} else if (size == 6 && (buf[0] & 0x40)) {
    106		code = buf[4];
    107		dev = buf[3];
    108		vendor = get_unaligned_be16(buf + 1);
    109
    110		if (vendor == 0x800f) {
    111			*ptoggle = (dev & 0x80) != 0;
    112			*protocol = RC_PROTO_RC6_MCE;
    113			dev &= 0x7f;
    114			dev_dbg(&ir->rc->dev,
    115				"ir hauppauge (rc6-mce): t%d vendor=%d dev=%d code=%d\n",
    116				*ptoggle, vendor, dev, code);
    117		} else {
    118			*ptoggle = 0;
    119			*protocol = RC_PROTO_RC6_6A_32;
    120			dev_dbg(&ir->rc->dev,
    121				"ir hauppauge (rc6-6a-32): vendor=%d dev=%d code=%d\n",
    122				vendor, dev, code);
    123		}
    124
    125		*scancode = RC_SCANCODE_RC6_6A(vendor, dev, code);
    126
    127		return 1;
    128	}
    129
    130	return 0;
    131}
    132
    133static int get_key_haup(struct IR_i2c *ir, enum rc_proto *protocol,
    134			u32 *scancode, u8 *toggle)
    135{
    136	return get_key_haup_common(ir, protocol, scancode, toggle, 3);
    137}
    138
    139static int get_key_haup_xvr(struct IR_i2c *ir, enum rc_proto *protocol,
    140			    u32 *scancode, u8 *toggle)
    141{
    142	int ret;
    143	unsigned char buf[1] = { 0 };
    144
    145	/*
    146	 * This is the same apparent "are you ready?" poll command observed
    147	 * watching Windows driver traffic and implemented in lirc_zilog. With
    148	 * this added, we get far saner remote behavior with z8 chips on usb
    149	 * connected devices, even with the default polling interval of 100ms.
    150	 */
    151	ret = i2c_master_send(ir->c, buf, 1);
    152	if (ret != 1)
    153		return (ret < 0) ? ret : -EINVAL;
    154
    155	return get_key_haup_common(ir, protocol, scancode, toggle, 6);
    156}
    157
    158static int get_key_pixelview(struct IR_i2c *ir, enum rc_proto *protocol,
    159			     u32 *scancode, u8 *toggle)
    160{
    161	int rc;
    162	unsigned char b;
    163
    164	/* poll IR chip */
    165	rc = i2c_master_recv(ir->c, &b, 1);
    166	if (rc != 1) {
    167		dev_dbg(&ir->rc->dev, "read error\n");
    168		if (rc < 0)
    169			return rc;
    170		return -EIO;
    171	}
    172
    173	*protocol = RC_PROTO_OTHER;
    174	*scancode = b;
    175	*toggle = 0;
    176	return 1;
    177}
    178
    179static int get_key_fusionhdtv(struct IR_i2c *ir, enum rc_proto *protocol,
    180			      u32 *scancode, u8 *toggle)
    181{
    182	int rc;
    183	unsigned char buf[4];
    184
    185	/* poll IR chip */
    186	rc = i2c_master_recv(ir->c, buf, 4);
    187	if (rc != 4) {
    188		dev_dbg(&ir->rc->dev, "read error\n");
    189		if (rc < 0)
    190			return rc;
    191		return -EIO;
    192	}
    193
    194	if (buf[0] != 0 || buf[1] != 0 || buf[2] != 0 || buf[3] != 0)
    195		dev_dbg(&ir->rc->dev, "%s: %*ph\n", __func__, 4, buf);
    196
    197	/* no key pressed or signal from other ir remote */
    198	if(buf[0] != 0x1 ||  buf[1] != 0xfe)
    199		return 0;
    200
    201	*protocol = RC_PROTO_UNKNOWN;
    202	*scancode = buf[2];
    203	*toggle = 0;
    204	return 1;
    205}
    206
    207static int get_key_knc1(struct IR_i2c *ir, enum rc_proto *protocol,
    208			u32 *scancode, u8 *toggle)
    209{
    210	int rc;
    211	unsigned char b;
    212
    213	/* poll IR chip */
    214	rc = i2c_master_recv(ir->c, &b, 1);
    215	if (rc != 1) {
    216		dev_dbg(&ir->rc->dev, "read error\n");
    217		if (rc < 0)
    218			return rc;
    219		return -EIO;
    220	}
    221
    222	/* it seems that 0xFE indicates that a button is still hold
    223	   down, while 0xff indicates that no button is hold
    224	   down. 0xfe sequences are sometimes interrupted by 0xFF */
    225
    226	dev_dbg(&ir->rc->dev, "key %02x\n", b);
    227
    228	if (b == 0xff)
    229		return 0;
    230
    231	if (b == 0xfe)
    232		/* keep old data */
    233		return 1;
    234
    235	*protocol = RC_PROTO_UNKNOWN;
    236	*scancode = b;
    237	*toggle = 0;
    238	return 1;
    239}
    240
    241static int get_key_avermedia_cardbus(struct IR_i2c *ir, enum rc_proto *protocol,
    242				     u32 *scancode, u8 *toggle)
    243{
    244	unsigned char subaddr, key, keygroup;
    245	struct i2c_msg msg[] = { { .addr = ir->c->addr, .flags = 0,
    246				   .buf = &subaddr, .len = 1},
    247				 { .addr = ir->c->addr, .flags = I2C_M_RD,
    248				  .buf = &key, .len = 1} };
    249	subaddr = 0x0d;
    250	if (2 != i2c_transfer(ir->c->adapter, msg, 2)) {
    251		dev_dbg(&ir->rc->dev, "read error\n");
    252		return -EIO;
    253	}
    254
    255	if (key == 0xff)
    256		return 0;
    257
    258	subaddr = 0x0b;
    259	msg[1].buf = &keygroup;
    260	if (2 != i2c_transfer(ir->c->adapter, msg, 2)) {
    261		dev_dbg(&ir->rc->dev, "read error\n");
    262		return -EIO;
    263	}
    264
    265	if (keygroup == 0xff)
    266		return 0;
    267
    268	dev_dbg(&ir->rc->dev, "read key 0x%02x/0x%02x\n", key, keygroup);
    269	if (keygroup < 2 || keygroup > 4) {
    270		dev_warn(&ir->rc->dev, "warning: invalid key group 0x%02x for key 0x%02x\n",
    271			 keygroup, key);
    272	}
    273	key |= (keygroup & 1) << 6;
    274
    275	*protocol = RC_PROTO_UNKNOWN;
    276	*scancode = key;
    277	if (ir->c->addr == 0x41) /* AVerMedia EM78P153 */
    278		*scancode |= keygroup << 8;
    279	*toggle = 0;
    280	return 1;
    281}
    282
    283/* ----------------------------------------------------------------------- */
    284
    285static int ir_key_poll(struct IR_i2c *ir)
    286{
    287	enum rc_proto protocol;
    288	u32 scancode;
    289	u8 toggle;
    290	int rc;
    291
    292	dev_dbg(&ir->rc->dev, "%s\n", __func__);
    293	rc = ir->get_key(ir, &protocol, &scancode, &toggle);
    294	if (rc < 0) {
    295		dev_warn(&ir->rc->dev, "error %d\n", rc);
    296		return rc;
    297	}
    298
    299	if (rc) {
    300		dev_dbg(&ir->rc->dev, "%s: proto = 0x%04x, scancode = 0x%08x\n",
    301			__func__, protocol, scancode);
    302		rc_keydown(ir->rc, protocol, scancode, toggle);
    303	}
    304	return 0;
    305}
    306
    307static void ir_work(struct work_struct *work)
    308{
    309	int rc;
    310	struct IR_i2c *ir = container_of(work, struct IR_i2c, work.work);
    311
    312	/*
    313	 * If the transmit code is holding the lock, skip polling for
    314	 * IR, we'll get it to it next time round
    315	 */
    316	if (mutex_trylock(&ir->lock)) {
    317		rc = ir_key_poll(ir);
    318		mutex_unlock(&ir->lock);
    319		if (rc == -ENODEV) {
    320			rc_unregister_device(ir->rc);
    321			ir->rc = NULL;
    322			return;
    323		}
    324	}
    325
    326	schedule_delayed_work(&ir->work, msecs_to_jiffies(ir->polling_interval));
    327}
    328
    329static int ir_open(struct rc_dev *dev)
    330{
    331	struct IR_i2c *ir = dev->priv;
    332
    333	schedule_delayed_work(&ir->work, 0);
    334
    335	return 0;
    336}
    337
    338static void ir_close(struct rc_dev *dev)
    339{
    340	struct IR_i2c *ir = dev->priv;
    341
    342	cancel_delayed_work_sync(&ir->work);
    343}
    344
    345/* Zilog Transmit Interface */
    346#define XTAL_FREQ		18432000
    347
    348#define ZILOG_SEND		0x80
    349#define ZILOG_UIR_END		0x40
    350#define ZILOG_INIT_END		0x20
    351#define ZILOG_LIR_END		0x10
    352
    353#define ZILOG_STATUS_OK		0x80
    354#define ZILOG_STATUS_TX		0x40
    355#define ZILOG_STATUS_SET	0x20
    356
    357/*
    358 * As you can see here, very few different lengths of pulse and space
    359 * can be encoded. This means that the hardware does not work well with
    360 * recorded IR. It's best to work with generated IR, like from ir-ctl or
    361 * the in-kernel encoders.
    362 */
    363struct code_block {
    364	u8	length;
    365	u16	pulse[7];	/* not aligned */
    366	u8	carrier_pulse;
    367	u8	carrier_space;
    368	u16	space[8];	/* not aligned */
    369	u8	codes[61];
    370	u8	csum[2];
    371} __packed;
    372
    373static int send_data_block(struct IR_i2c *ir, int cmd,
    374			   struct code_block *code_block)
    375{
    376	int i, j, ret;
    377	u8 buf[5], *p;
    378
    379	p = &code_block->length;
    380	for (i = 0; p < code_block->csum; i++)
    381		code_block->csum[i & 1] ^= *p++;
    382
    383	p = &code_block->length;
    384
    385	for (i = 0; i < sizeof(*code_block);) {
    386		int tosend = sizeof(*code_block) - i;
    387
    388		if (tosend > 4)
    389			tosend = 4;
    390		buf[0] = i + 1;
    391		for (j = 0; j < tosend; ++j)
    392			buf[1 + j] = p[i + j];
    393		dev_dbg(&ir->rc->dev, "%*ph", tosend + 1, buf);
    394		ret = i2c_master_send(ir->tx_c, buf, tosend + 1);
    395		if (ret != tosend + 1) {
    396			dev_dbg(&ir->rc->dev,
    397				"i2c_master_send failed with %d\n", ret);
    398			return ret < 0 ? ret : -EIO;
    399		}
    400		i += tosend;
    401	}
    402
    403	buf[0] = 0;
    404	buf[1] = cmd;
    405	ret = i2c_master_send(ir->tx_c, buf, 2);
    406	if (ret != 2) {
    407		dev_err(&ir->rc->dev, "i2c_master_send failed with %d\n", ret);
    408		return ret < 0 ? ret : -EIO;
    409	}
    410
    411	usleep_range(2000, 5000);
    412
    413	ret = i2c_master_send(ir->tx_c, buf, 1);
    414	if (ret != 1) {
    415		dev_err(&ir->rc->dev, "i2c_master_send failed with %d\n", ret);
    416		return ret < 0 ? ret : -EIO;
    417	}
    418
    419	return 0;
    420}
    421
    422static int zilog_init(struct IR_i2c *ir)
    423{
    424	struct code_block code_block = { .length = sizeof(code_block) };
    425	u8 buf[4];
    426	int ret;
    427
    428	put_unaligned_be16(0x1000, &code_block.pulse[3]);
    429
    430	ret = send_data_block(ir, ZILOG_INIT_END, &code_block);
    431	if (ret)
    432		return ret;
    433
    434	ret = i2c_master_recv(ir->tx_c, buf, 4);
    435	if (ret != 4) {
    436		dev_err(&ir->c->dev, "failed to retrieve firmware version: %d\n",
    437			ret);
    438		return ret < 0 ? ret : -EIO;
    439	}
    440
    441	dev_info(&ir->c->dev, "Zilog/Hauppauge IR blaster firmware version %d.%d.%d\n",
    442		 buf[1], buf[2], buf[3]);
    443
    444	return 0;
    445}
    446
    447/*
    448 * If the last slot for pulse is the same as the current slot for pulse,
    449 * then use slot no 7.
    450 */
    451static void copy_codes(u8 *dst, u8 *src, unsigned int count)
    452{
    453	u8 c, last = 0xff;
    454
    455	while (count--) {
    456		c = *src++;
    457		if ((c & 0xf0) == last) {
    458			*dst++ = 0x70 | (c & 0xf);
    459		} else {
    460			*dst++ = c;
    461			last = c & 0xf0;
    462		}
    463	}
    464}
    465
    466/*
    467 * When looking for repeats, we don't care about the trailing space. This
    468 * is set to the shortest possible anyway.
    469 */
    470static int cmp_no_trail(u8 *a, u8 *b, unsigned int count)
    471{
    472	while (--count) {
    473		if (*a++ != *b++)
    474			return 1;
    475	}
    476
    477	return (*a & 0xf0) - (*b & 0xf0);
    478}
    479
    480static int find_slot(u16 *array, unsigned int size, u16 val)
    481{
    482	int i;
    483
    484	for (i = 0; i < size; i++) {
    485		if (get_unaligned_be16(&array[i]) == val) {
    486			return i;
    487		} else if (!array[i]) {
    488			put_unaligned_be16(val, &array[i]);
    489			return i;
    490		}
    491	}
    492
    493	return -1;
    494}
    495
    496static int zilog_ir_format(struct rc_dev *rcdev, unsigned int *txbuf,
    497			   unsigned int count, struct code_block *code_block)
    498{
    499	struct IR_i2c *ir = rcdev->priv;
    500	int rep, i, l, p = 0, s, c = 0;
    501	bool repeating;
    502	u8 codes[174];
    503
    504	code_block->carrier_pulse = DIV_ROUND_CLOSEST(
    505			ir->duty_cycle * XTAL_FREQ / 1000, ir->carrier);
    506	code_block->carrier_space = DIV_ROUND_CLOSEST(
    507			(100 - ir->duty_cycle) * XTAL_FREQ / 1000, ir->carrier);
    508
    509	for (i = 0; i < count; i++) {
    510		if (c >= ARRAY_SIZE(codes) - 1) {
    511			dev_warn(&rcdev->dev, "IR too long, cannot transmit\n");
    512			return -EINVAL;
    513		}
    514
    515		/*
    516		 * Lengths more than 142220us cannot be encoded; also
    517		 * this checks for multiply overflow
    518		 */
    519		if (txbuf[i] > 142220)
    520			return -EINVAL;
    521
    522		l = DIV_ROUND_CLOSEST((XTAL_FREQ / 1000) * txbuf[i], 40000);
    523
    524		if (i & 1) {
    525			s = find_slot(code_block->space,
    526				      ARRAY_SIZE(code_block->space), l);
    527			if (s == -1) {
    528				dev_warn(&rcdev->dev, "Too many different lengths spaces, cannot transmit");
    529				return -EINVAL;
    530			}
    531
    532			/* We have a pulse and space */
    533			codes[c++] = (p << 4) | s;
    534		} else {
    535			p = find_slot(code_block->pulse,
    536				      ARRAY_SIZE(code_block->pulse), l);
    537			if (p == -1) {
    538				dev_warn(&rcdev->dev, "Too many different lengths pulses, cannot transmit");
    539				return -EINVAL;
    540			}
    541		}
    542	}
    543
    544	/* We have to encode the trailing pulse. Find the shortest space */
    545	s = 0;
    546	for (i = 1; i < ARRAY_SIZE(code_block->space); i++) {
    547		u16 d = get_unaligned_be16(&code_block->space[i]);
    548
    549		if (get_unaligned_be16(&code_block->space[s]) > d)
    550			s = i;
    551	}
    552
    553	codes[c++] = (p << 4) | s;
    554
    555	dev_dbg(&rcdev->dev, "generated %d codes\n", c);
    556
    557	/*
    558	 * Are the last N codes (so pulse + space) repeating 3 times?
    559	 * if so we can shorten the codes list and use code 0xc0 to repeat
    560	 * them.
    561	 */
    562	repeating = false;
    563
    564	for (rep = c / 3; rep >= 1; rep--) {
    565		if (!memcmp(&codes[c - rep * 3], &codes[c - rep * 2], rep) &&
    566		    !cmp_no_trail(&codes[c - rep], &codes[c - rep * 2], rep)) {
    567			repeating = true;
    568			break;
    569		}
    570	}
    571
    572	if (repeating) {
    573		/* first copy any leading non-repeating */
    574		int leading = c - rep * 3;
    575
    576		if (leading >= ARRAY_SIZE(code_block->codes) - 3 - rep) {
    577			dev_warn(&rcdev->dev, "IR too long, cannot transmit\n");
    578			return -EINVAL;
    579		}
    580
    581		dev_dbg(&rcdev->dev, "found trailing %d repeat\n", rep);
    582		copy_codes(code_block->codes, codes, leading);
    583		code_block->codes[leading] = 0x82;
    584		copy_codes(code_block->codes + leading + 1, codes + leading,
    585			   rep);
    586		c = leading + 1 + rep;
    587		code_block->codes[c++] = 0xc0;
    588	} else {
    589		if (c >= ARRAY_SIZE(code_block->codes) - 3) {
    590			dev_warn(&rcdev->dev, "IR too long, cannot transmit\n");
    591			return -EINVAL;
    592		}
    593
    594		dev_dbg(&rcdev->dev, "found no trailing repeat\n");
    595		code_block->codes[0] = 0x82;
    596		copy_codes(code_block->codes + 1, codes, c);
    597		c++;
    598		code_block->codes[c++] = 0xc4;
    599	}
    600
    601	while (c < ARRAY_SIZE(code_block->codes))
    602		code_block->codes[c++] = 0x83;
    603
    604	return 0;
    605}
    606
    607static int zilog_tx(struct rc_dev *rcdev, unsigned int *txbuf,
    608		    unsigned int count)
    609{
    610	struct IR_i2c *ir = rcdev->priv;
    611	struct code_block code_block = { .length = sizeof(code_block) };
    612	u8 buf[2];
    613	int ret, i;
    614
    615	ret = zilog_ir_format(rcdev, txbuf, count, &code_block);
    616	if (ret)
    617		return ret;
    618
    619	ret = mutex_lock_interruptible(&ir->lock);
    620	if (ret)
    621		return ret;
    622
    623	ret = send_data_block(ir, ZILOG_UIR_END, &code_block);
    624	if (ret)
    625		goto out_unlock;
    626
    627	ret = i2c_master_recv(ir->tx_c, buf, 1);
    628	if (ret != 1) {
    629		dev_err(&ir->rc->dev, "i2c_master_recv failed with %d\n", ret);
    630		goto out_unlock;
    631	}
    632
    633	dev_dbg(&ir->rc->dev, "code set status: %02x\n", buf[0]);
    634
    635	if (buf[0] != (ZILOG_STATUS_OK | ZILOG_STATUS_SET)) {
    636		dev_err(&ir->rc->dev, "unexpected IR TX response %02x\n",
    637			buf[0]);
    638		ret = -EIO;
    639		goto out_unlock;
    640	}
    641
    642	buf[0] = 0x00;
    643	buf[1] = ZILOG_SEND;
    644
    645	ret = i2c_master_send(ir->tx_c, buf, 2);
    646	if (ret != 2) {
    647		dev_err(&ir->rc->dev, "i2c_master_send failed with %d\n", ret);
    648		if (ret >= 0)
    649			ret = -EIO;
    650		goto out_unlock;
    651	}
    652
    653	dev_dbg(&ir->rc->dev, "send command sent\n");
    654
    655	/*
    656	 * This bit NAKs until the device is ready, so we retry it
    657	 * sleeping a bit each time.  This seems to be what the windows
    658	 * driver does, approximately.
    659	 * Try for up to 1s.
    660	 */
    661	for (i = 0; i < 20; ++i) {
    662		set_current_state(TASK_UNINTERRUPTIBLE);
    663		schedule_timeout(msecs_to_jiffies(50));
    664		ret = i2c_master_send(ir->tx_c, buf, 1);
    665		if (ret == 1)
    666			break;
    667		dev_dbg(&ir->rc->dev,
    668			"NAK expected: i2c_master_send failed with %d (try %d)\n",
    669			ret, i + 1);
    670	}
    671
    672	if (ret != 1) {
    673		dev_err(&ir->rc->dev,
    674			"IR TX chip never got ready: last i2c_master_send failed with %d\n",
    675			ret);
    676		if (ret >= 0)
    677			ret = -EIO;
    678		goto out_unlock;
    679	}
    680
    681	ret = i2c_master_recv(ir->tx_c, buf, 1);
    682	if (ret != 1) {
    683		dev_err(&ir->rc->dev, "i2c_master_recv failed with %d\n", ret);
    684		ret = -EIO;
    685		goto out_unlock;
    686	} else if (buf[0] != ZILOG_STATUS_OK) {
    687		dev_err(&ir->rc->dev, "unexpected IR TX response #2: %02x\n",
    688			buf[0]);
    689		ret = -EIO;
    690		goto out_unlock;
    691	}
    692	dev_dbg(&ir->rc->dev, "transmit complete\n");
    693
    694	/* Oh good, it worked */
    695	ret = count;
    696out_unlock:
    697	mutex_unlock(&ir->lock);
    698
    699	return ret;
    700}
    701
    702static int zilog_tx_carrier(struct rc_dev *dev, u32 carrier)
    703{
    704	struct IR_i2c *ir = dev->priv;
    705
    706	if (carrier > 500000 || carrier < 20000)
    707		return -EINVAL;
    708
    709	ir->carrier = carrier;
    710
    711	return 0;
    712}
    713
    714static int zilog_tx_duty_cycle(struct rc_dev *dev, u32 duty_cycle)
    715{
    716	struct IR_i2c *ir = dev->priv;
    717
    718	ir->duty_cycle = duty_cycle;
    719
    720	return 0;
    721}
    722
    723static int ir_probe(struct i2c_client *client, const struct i2c_device_id *id)
    724{
    725	char *ir_codes = NULL;
    726	const char *name = NULL;
    727	u64 rc_proto = RC_PROTO_BIT_UNKNOWN;
    728	struct IR_i2c *ir;
    729	struct rc_dev *rc = NULL;
    730	struct i2c_adapter *adap = client->adapter;
    731	unsigned short addr = client->addr;
    732	bool probe_tx = (id->driver_data & FLAG_TX) != 0;
    733	int err;
    734
    735	if ((id->driver_data & FLAG_HDPVR) && !enable_hdpvr) {
    736		dev_err(&client->dev, "IR for HDPVR is known to cause problems during recording, use enable_hdpvr modparam to enable\n");
    737		return -ENODEV;
    738	}
    739
    740	ir = devm_kzalloc(&client->dev, sizeof(*ir), GFP_KERNEL);
    741	if (!ir)
    742		return -ENOMEM;
    743
    744	ir->c = client;
    745	ir->polling_interval = DEFAULT_POLLING_INTERVAL;
    746	i2c_set_clientdata(client, ir);
    747
    748	switch(addr) {
    749	case 0x64:
    750		name        = "Pixelview";
    751		ir->get_key = get_key_pixelview;
    752		rc_proto    = RC_PROTO_BIT_OTHER;
    753		ir_codes    = RC_MAP_EMPTY;
    754		break;
    755	case 0x18:
    756	case 0x1f:
    757	case 0x1a:
    758		name        = "Hauppauge";
    759		ir->get_key = get_key_haup;
    760		rc_proto    = RC_PROTO_BIT_RC5;
    761		ir_codes    = RC_MAP_HAUPPAUGE;
    762		break;
    763	case 0x30:
    764		name        = "KNC One";
    765		ir->get_key = get_key_knc1;
    766		rc_proto    = RC_PROTO_BIT_OTHER;
    767		ir_codes    = RC_MAP_EMPTY;
    768		break;
    769	case 0x6b:
    770		name        = "FusionHDTV";
    771		ir->get_key = get_key_fusionhdtv;
    772		rc_proto    = RC_PROTO_BIT_UNKNOWN;
    773		ir_codes    = RC_MAP_FUSIONHDTV_MCE;
    774		break;
    775	case 0x40:
    776		name        = "AVerMedia Cardbus remote";
    777		ir->get_key = get_key_avermedia_cardbus;
    778		rc_proto    = RC_PROTO_BIT_OTHER;
    779		ir_codes    = RC_MAP_AVERMEDIA_CARDBUS;
    780		break;
    781	case 0x41:
    782		name        = "AVerMedia EM78P153";
    783		ir->get_key = get_key_avermedia_cardbus;
    784		rc_proto    = RC_PROTO_BIT_OTHER;
    785		/* RM-KV remote, seems to be same as RM-K6 */
    786		ir_codes    = RC_MAP_AVERMEDIA_M733A_RM_K6;
    787		break;
    788	case 0x71:
    789		name        = "Hauppauge/Zilog Z8";
    790		ir->get_key = get_key_haup_xvr;
    791		rc_proto    = RC_PROTO_BIT_RC5 | RC_PROTO_BIT_RC6_MCE |
    792							RC_PROTO_BIT_RC6_6A_32;
    793		ir_codes    = RC_MAP_HAUPPAUGE;
    794		ir->polling_interval = 125;
    795		probe_tx = true;
    796		break;
    797	}
    798
    799	/* Let the caller override settings */
    800	if (client->dev.platform_data) {
    801		const struct IR_i2c_init_data *init_data =
    802						client->dev.platform_data;
    803
    804		ir_codes = init_data->ir_codes;
    805		rc = init_data->rc_dev;
    806
    807		name = init_data->name;
    808		if (init_data->type)
    809			rc_proto = init_data->type;
    810
    811		if (init_data->polling_interval)
    812			ir->polling_interval = init_data->polling_interval;
    813
    814		switch (init_data->internal_get_key_func) {
    815		case IR_KBD_GET_KEY_CUSTOM:
    816			/* The bridge driver provided us its own function */
    817			ir->get_key = init_data->get_key;
    818			break;
    819		case IR_KBD_GET_KEY_PIXELVIEW:
    820			ir->get_key = get_key_pixelview;
    821			break;
    822		case IR_KBD_GET_KEY_HAUP:
    823			ir->get_key = get_key_haup;
    824			break;
    825		case IR_KBD_GET_KEY_KNC1:
    826			ir->get_key = get_key_knc1;
    827			break;
    828		case IR_KBD_GET_KEY_FUSIONHDTV:
    829			ir->get_key = get_key_fusionhdtv;
    830			break;
    831		case IR_KBD_GET_KEY_HAUP_XVR:
    832			ir->get_key = get_key_haup_xvr;
    833			break;
    834		case IR_KBD_GET_KEY_AVERMEDIA_CARDBUS:
    835			ir->get_key = get_key_avermedia_cardbus;
    836			break;
    837		}
    838	}
    839
    840	if (!rc) {
    841		/*
    842		 * If platform_data doesn't specify rc_dev, initialize it
    843		 * internally
    844		 */
    845		rc = rc_allocate_device(RC_DRIVER_SCANCODE);
    846		if (!rc)
    847			return -ENOMEM;
    848	}
    849	ir->rc = rc;
    850
    851	/* Make sure we are all setup before going on */
    852	if (!name || !ir->get_key || !rc_proto || !ir_codes) {
    853		dev_warn(&client->dev, "Unsupported device at address 0x%02x\n",
    854			 addr);
    855		err = -ENODEV;
    856		goto err_out_free;
    857	}
    858
    859	ir->ir_codes = ir_codes;
    860
    861	snprintf(ir->phys, sizeof(ir->phys), "%s/%s", dev_name(&adap->dev),
    862		 dev_name(&client->dev));
    863
    864	/*
    865	 * Initialize input_dev fields
    866	 * It doesn't make sense to allow overriding them via platform_data
    867	 */
    868	rc->input_id.bustype = BUS_I2C;
    869	rc->input_phys       = ir->phys;
    870	rc->device_name	     = name;
    871	rc->dev.parent       = &client->dev;
    872	rc->priv             = ir;
    873	rc->open             = ir_open;
    874	rc->close            = ir_close;
    875
    876	/*
    877	 * Initialize the other fields of rc_dev
    878	 */
    879	rc->map_name       = ir->ir_codes;
    880	rc->allowed_protocols = rc_proto;
    881	if (!rc->driver_name)
    882		rc->driver_name = KBUILD_MODNAME;
    883
    884	mutex_init(&ir->lock);
    885
    886	INIT_DELAYED_WORK(&ir->work, ir_work);
    887
    888	if (probe_tx) {
    889		ir->tx_c = i2c_new_dummy_device(client->adapter, 0x70);
    890		if (IS_ERR(ir->tx_c)) {
    891			dev_err(&client->dev, "failed to setup tx i2c address");
    892			err = PTR_ERR(ir->tx_c);
    893			goto err_out_free;
    894		} else if (!zilog_init(ir)) {
    895			ir->carrier = 38000;
    896			ir->duty_cycle = 40;
    897			rc->tx_ir = zilog_tx;
    898			rc->s_tx_carrier = zilog_tx_carrier;
    899			rc->s_tx_duty_cycle = zilog_tx_duty_cycle;
    900		}
    901	}
    902
    903	err = rc_register_device(rc);
    904	if (err)
    905		goto err_out_free;
    906
    907	return 0;
    908
    909 err_out_free:
    910	if (!IS_ERR(ir->tx_c))
    911		i2c_unregister_device(ir->tx_c);
    912
    913	/* Only frees rc if it were allocated internally */
    914	rc_free_device(rc);
    915	return err;
    916}
    917
    918static int ir_remove(struct i2c_client *client)
    919{
    920	struct IR_i2c *ir = i2c_get_clientdata(client);
    921
    922	cancel_delayed_work_sync(&ir->work);
    923
    924	i2c_unregister_device(ir->tx_c);
    925
    926	rc_unregister_device(ir->rc);
    927
    928	return 0;
    929}
    930
    931static const struct i2c_device_id ir_kbd_id[] = {
    932	/* Generic entry for any IR receiver */
    933	{ "ir_video", 0 },
    934	/* IR device specific entries should be added here */
    935	{ "ir_z8f0811_haup", FLAG_TX },
    936	{ "ir_z8f0811_hdpvr", FLAG_TX | FLAG_HDPVR },
    937	{ }
    938};
    939MODULE_DEVICE_TABLE(i2c, ir_kbd_id);
    940
    941static struct i2c_driver ir_kbd_driver = {
    942	.driver = {
    943		.name   = "ir-kbd-i2c",
    944	},
    945	.probe          = ir_probe,
    946	.remove         = ir_remove,
    947	.id_table       = ir_kbd_id,
    948};
    949
    950module_i2c_driver(ir_kbd_driver);
    951
    952/* ----------------------------------------------------------------------- */
    953
    954MODULE_AUTHOR("Gerd Knorr, Michal Kochanowicz, Christoph Bartelmus, Ulrich Mueller");
    955MODULE_DESCRIPTION("input driver for i2c IR remote controls");
    956MODULE_LICENSE("GPL");