/drivers/media/video/cx25840/cx25840-ir.c

   1/*
   2 *  Driver for the Conexant CX2584x Audio/Video decoder chip and related cores
   3 *
   4 *  Integrated Consumer Infrared Controller
   5 *
   6 *  Copyright (C) 2010  Andy Walls <awalls@md.metrocast.net>
   7 *
   8 *  This program is free software; you can redistribute it and/or
   9 *  modify it under the terms of the GNU General Public License
  10 *  as published by the Free Software Foundation; either version 2
  11 *  of the License, or (at your option) any later version.
  12 *
  13 *  This program is distributed in the hope that it will be useful,
  14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 *  GNU General Public License for more details.
  17 *
  18 *  You should have received a copy of the GNU General Public License
  19 *  along with this program; if not, write to the Free Software
  20 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  21 *  02110-1301, USA.
  22 */
  23
  24#include <linux/slab.h>
  25#include <linux/kfifo.h>
  26#include <media/cx25840.h>
  27#include <media/rc-core.h>
  28
  29#include "cx25840-core.h"
  30
  31static unsigned int ir_debug;
  32module_param(ir_debug, int, 0644);
  33MODULE_PARM_DESC(ir_debug, "enable integrated IR debug messages");
  34
  35#define CX25840_IR_REG_BASE 	0x200
  36
  37#define CX25840_IR_CNTRL_REG	0x200
  38#define CNTRL_WIN_3_3	0x00000000
  39#define CNTRL_WIN_4_3	0x00000001
  40#define CNTRL_WIN_3_4	0x00000002
  41#define CNTRL_WIN_4_4	0x00000003
  42#define CNTRL_WIN	0x00000003
  43#define CNTRL_EDG_NONE	0x00000000
  44#define CNTRL_EDG_FALL	0x00000004
  45#define CNTRL_EDG_RISE	0x00000008
  46#define CNTRL_EDG_BOTH	0x0000000C
  47#define CNTRL_EDG	0x0000000C
  48#define CNTRL_DMD	0x00000010
  49#define CNTRL_MOD	0x00000020
  50#define CNTRL_RFE	0x00000040
  51#define CNTRL_TFE	0x00000080
  52#define CNTRL_RXE	0x00000100
  53#define CNTRL_TXE	0x00000200
  54#define CNTRL_RIC	0x00000400
  55#define CNTRL_TIC	0x00000800
  56#define CNTRL_CPL	0x00001000
  57#define CNTRL_LBM	0x00002000
  58#define CNTRL_R		0x00004000
  59
  60#define CX25840_IR_TXCLK_REG	0x204
  61#define TXCLK_TCD	0x0000FFFF
  62
  63#define CX25840_IR_RXCLK_REG	0x208
  64#define RXCLK_RCD	0x0000FFFF
  65
  66#define CX25840_IR_CDUTY_REG	0x20C
  67#define CDUTY_CDC	0x0000000F
  68
  69#define CX25840_IR_STATS_REG	0x210
  70#define STATS_RTO	0x00000001
  71#define STATS_ROR	0x00000002
  72#define STATS_RBY	0x00000004
  73#define STATS_TBY	0x00000008
  74#define STATS_RSR	0x00000010
  75#define STATS_TSR	0x00000020
  76
  77#define CX25840_IR_IRQEN_REG	0x214
  78#define IRQEN_RTE	0x00000001
  79#define IRQEN_ROE	0x00000002
  80#define IRQEN_RSE	0x00000010
  81#define IRQEN_TSE	0x00000020
  82#define IRQEN_MSK	0x00000033
  83
  84#define CX25840_IR_FILTR_REG	0x218
  85#define FILTR_LPF	0x0000FFFF
  86
  87#define CX25840_IR_FIFO_REG	0x23C
  88#define FIFO_RXTX	0x0000FFFF
  89#define FIFO_RXTX_LVL	0x00010000
  90#define FIFO_RXTX_RTO	0x0001FFFF
  91#define FIFO_RX_NDV	0x00020000
  92#define FIFO_RX_DEPTH	8
  93#define FIFO_TX_DEPTH	8
  94
  95#define CX25840_VIDCLK_FREQ	108000000 /* 108 MHz, BT.656 */
  96#define CX25840_IR_REFCLK_FREQ	(CX25840_VIDCLK_FREQ / 2)
  97
  98/*
  99 * We use this union internally for convenience, but callers to tx_write
 100 * and rx_read will be expecting records of type struct ir_raw_event.
 101 * Always ensure the size of this union is dictated by struct ir_raw_event.
 102 */
 103union cx25840_ir_fifo_rec {
 104	u32 hw_fifo_data;
 105	struct ir_raw_event ir_core_data;
 106};
 107
 108#define CX25840_IR_RX_KFIFO_SIZE    (256 * sizeof(union cx25840_ir_fifo_rec))
 109#define CX25840_IR_TX_KFIFO_SIZE    (256 * sizeof(union cx25840_ir_fifo_rec))
 110
 111struct cx25840_ir_state {
 112	struct i2c_client *c;
 113
 114	struct v4l2_subdev_ir_parameters rx_params;
 115	struct mutex rx_params_lock; /* protects Rx parameter settings cache */
 116	atomic_t rxclk_divider;
 117	atomic_t rx_invert;
 118
 119	struct kfifo rx_kfifo;
 120	spinlock_t rx_kfifo_lock; /* protect Rx data kfifo */
 121
 122	struct v4l2_subdev_ir_parameters tx_params;
 123	struct mutex tx_params_lock; /* protects Tx parameter settings cache */
 124	atomic_t txclk_divider;
 125};
 126
 127static inline struct cx25840_ir_state *to_ir_state(struct v4l2_subdev *sd)
 128{
 129	struct cx25840_state *state = to_state(sd);
 130	return state ? state->ir_state : NULL;
 131}
 132
 133
 134/*
 135 * Rx and Tx Clock Divider register computations
 136 *
 137 * Note the largest clock divider value of 0xffff corresponds to:
 138 * 	(0xffff + 1) * 1000 / 108/2 MHz = 1,213,629.629... ns
 139 * which fits in 21 bits, so we'll use unsigned int for time arguments.
 140 */
 141static inline u16 count_to_clock_divider(unsigned int d)
 142{
 143	if (d > RXCLK_RCD + 1)
 144		d = RXCLK_RCD;
 145	else if (d < 2)
 146		d = 1;
 147	else
 148		d--;
 149	return (u16) d;
 150}
 151
 152static inline u16 ns_to_clock_divider(unsigned int ns)
 153{
 154	return count_to_clock_divider(
 155		DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ / 1000000 * ns, 1000));
 156}
 157
 158static inline unsigned int clock_divider_to_ns(unsigned int divider)
 159{
 160	/* Period of the Rx or Tx clock in ns */
 161	return DIV_ROUND_CLOSEST((divider + 1) * 1000,
 162				 CX25840_IR_REFCLK_FREQ / 1000000);
 163}
 164
 165static inline u16 carrier_freq_to_clock_divider(unsigned int freq)
 166{
 167	return count_to_clock_divider(
 168			  DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, freq * 16));
 169}
 170
 171static inline unsigned int clock_divider_to_carrier_freq(unsigned int divider)
 172{
 173	return DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, (divider + 1) * 16);
 174}
 175
 176static inline u16 freq_to_clock_divider(unsigned int freq,
 177					unsigned int rollovers)
 178{
 179	return count_to_clock_divider(
 180		   DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, freq * rollovers));
 181}
 182
 183static inline unsigned int clock_divider_to_freq(unsigned int divider,
 184						 unsigned int rollovers)
 185{
 186	return DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ,
 187				 (divider + 1) * rollovers);
 188}
 189
 190/*
 191 * Low Pass Filter register calculations
 192 *
 193 * Note the largest count value of 0xffff corresponds to:
 194 * 	0xffff * 1000 / 108/2 MHz = 1,213,611.11... ns
 195 * which fits in 21 bits, so we'll use unsigned int for time arguments.
 196 */
 197static inline u16 count_to_lpf_count(unsigned int d)
 198{
 199	if (d > FILTR_LPF)
 200		d = FILTR_LPF;
 201	else if (d < 4)
 202		d = 0;
 203	return (u16) d;
 204}
 205
 206static inline u16 ns_to_lpf_count(unsigned int ns)
 207{
 208	return count_to_lpf_count(
 209		DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ / 1000000 * ns, 1000));
 210}
 211
 212static inline unsigned int lpf_count_to_ns(unsigned int count)
 213{
 214	/* Duration of the Low Pass Filter rejection window in ns */
 215	return DIV_ROUND_CLOSEST(count * 1000,
 216				 CX25840_IR_REFCLK_FREQ / 1000000);
 217}
 218
 219static inline unsigned int lpf_count_to_us(unsigned int count)
 220{
 221	/* Duration of the Low Pass Filter rejection window in us */
 222	return DIV_ROUND_CLOSEST(count, CX25840_IR_REFCLK_FREQ / 1000000);
 223}
 224
 225/*
 226 * FIFO register pulse width count compuations
 227 */
 228static u32 clock_divider_to_resolution(u16 divider)
 229{
 230	/*
 231	 * Resolution is the duration of 1 tick of the readable portion of
 232	 * of the pulse width counter as read from the FIFO.  The two lsb's are
 233	 * not readable, hence the << 2.  This function returns ns.
 234	 */
 235	return DIV_ROUND_CLOSEST((1 << 2)  * ((u32) divider + 1) * 1000,
 236				 CX25840_IR_REFCLK_FREQ / 1000000);
 237}
 238
 239static u64 pulse_width_count_to_ns(u16 count, u16 divider)
 240{
 241	u64 n;
 242	u32 rem;
 243
 244	/*
 245	 * The 2 lsb's of the pulse width timer count are not readable, hence
 246	 * the (count << 2) | 0x3
 247	 */
 248	n = (((u64) count << 2) | 0x3) * (divider + 1) * 1000; /* millicycles */
 249	rem = do_div(n, CX25840_IR_REFCLK_FREQ / 1000000);     /* / MHz => ns */
 250	if (rem >= CX25840_IR_REFCLK_FREQ / 1000000 / 2)
 251		n++;
 252	return n;
 253}
 254
 255#if 0
 256/* Keep as we will need this for Transmit functionality */
 257static u16 ns_to_pulse_width_count(u32 ns, u16 divider)
 258{
 259	u64 n;
 260	u32 d;
 261	u32 rem;
 262
 263	/*
 264	 * The 2 lsb's of the pulse width timer count are not accessible, hence
 265	 * the (1 << 2)
 266	 */
 267	n = ((u64) ns) * CX25840_IR_REFCLK_FREQ / 1000000; /* millicycles */
 268	d = (1 << 2) * ((u32) divider + 1) * 1000; /* millicycles/count */
 269	rem = do_div(n, d);
 270	if (rem >= d / 2)
 271		n++;
 272
 273	if (n > FIFO_RXTX)
 274		n = FIFO_RXTX;
 275	else if (n == 0)
 276		n = 1;
 277	return (u16) n;
 278}
 279
 280#endif
 281static unsigned int pulse_width_count_to_us(u16 count, u16 divider)
 282{
 283	u64 n;
 284	u32 rem;
 285
 286	/*
 287	 * The 2 lsb's of the pulse width timer count are not readable, hence
 288	 * the (count << 2) | 0x3
 289	 */
 290	n = (((u64) count << 2) | 0x3) * (divider + 1);    /* cycles      */
 291	rem = do_div(n, CX25840_IR_REFCLK_FREQ / 1000000); /* / MHz => us */
 292	if (rem >= CX25840_IR_REFCLK_FREQ / 1000000 / 2)
 293		n++;
 294	return (unsigned int) n;
 295}
 296
 297/*
 298 * Pulse Clocks computations: Combined Pulse Width Count & Rx Clock Counts
 299 *
 300 * The total pulse clock count is an 18 bit pulse width timer count as the most
 301 * significant part and (up to) 16 bit clock divider count as a modulus.
 302 * When the Rx clock divider ticks down to 0, it increments the 18 bit pulse
 303 * width timer count's least significant bit.
 304 */
 305static u64 ns_to_pulse_clocks(u32 ns)
 306{
 307	u64 clocks;
 308	u32 rem;
 309	clocks = CX25840_IR_REFCLK_FREQ / 1000000 * (u64) ns; /* millicycles  */
 310	rem = do_div(clocks, 1000);                         /* /1000 = cycles */
 311	if (rem >= 1000 / 2)
 312		clocks++;
 313	return clocks;
 314}
 315
 316static u16 pulse_clocks_to_clock_divider(u64 count)
 317{
 318	u32 rem;
 319
 320	rem = do_div(count, (FIFO_RXTX << 2) | 0x3);
 321
 322	/* net result needs to be rounded down and decremented by 1 */
 323	if (count > RXCLK_RCD + 1)
 324		count = RXCLK_RCD;
 325	else if (count < 2)
 326		count = 1;
 327	else
 328		count--;
 329	return (u16) count;
 330}
 331
 332/*
 333 * IR Control Register helpers
 334 */
 335enum tx_fifo_watermark {
 336	TX_FIFO_HALF_EMPTY = 0,
 337	TX_FIFO_EMPTY      = CNTRL_TIC,
 338};
 339
 340enum rx_fifo_watermark {
 341	RX_FIFO_HALF_FULL = 0,
 342	RX_FIFO_NOT_EMPTY = CNTRL_RIC,
 343};
 344
 345static inline void control_tx_irq_watermark(struct i2c_client *c,
 346					    enum tx_fifo_watermark level)
 347{
 348	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_TIC, level);
 349}
 350
 351static inline void control_rx_irq_watermark(struct i2c_client *c,
 352					    enum rx_fifo_watermark level)
 353{
 354	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_RIC, level);
 355}
 356
 357static inline void control_tx_enable(struct i2c_client *c, bool enable)
 358{
 359	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~(CNTRL_TXE | CNTRL_TFE),
 360			enable ? (CNTRL_TXE | CNTRL_TFE) : 0);
 361}
 362
 363static inline void control_rx_enable(struct i2c_client *c, bool enable)
 364{
 365	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~(CNTRL_RXE | CNTRL_RFE),
 366			enable ? (CNTRL_RXE | CNTRL_RFE) : 0);
 367}
 368
 369static inline void control_tx_modulation_enable(struct i2c_client *c,
 370						bool enable)
 371{
 372	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_MOD,
 373			enable ? CNTRL_MOD : 0);
 374}
 375
 376static inline void control_rx_demodulation_enable(struct i2c_client *c,
 377						  bool enable)
 378{
 379	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_DMD,
 380			enable ? CNTRL_DMD : 0);
 381}
 382
 383static inline void control_rx_s_edge_detection(struct i2c_client *c,
 384					       u32 edge_types)
 385{
 386	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_EDG_BOTH,
 387			edge_types & CNTRL_EDG_BOTH);
 388}
 389
 390static void control_rx_s_carrier_window(struct i2c_client *c,
 391					unsigned int carrier,
 392					unsigned int *carrier_range_low,
 393					unsigned int *carrier_range_high)
 394{
 395	u32 v;
 396	unsigned int c16 = carrier * 16;
 397
 398	if (*carrier_range_low < DIV_ROUND_CLOSEST(c16, 16 + 3)) {
 399		v = CNTRL_WIN_3_4;
 400		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 4);
 401	} else {
 402		v = CNTRL_WIN_3_3;
 403		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 3);
 404	}
 405
 406	if (*carrier_range_high > DIV_ROUND_CLOSEST(c16, 16 - 3)) {
 407		v |= CNTRL_WIN_4_3;
 408		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 4);
 409	} else {
 410		v |= CNTRL_WIN_3_3;
 411		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 3);
 412	}
 413	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_WIN, v);
 414}
 415
 416static inline void control_tx_polarity_invert(struct i2c_client *c,
 417					      bool invert)
 418{
 419	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_CPL,
 420			invert ? CNTRL_CPL : 0);
 421}
 422
 423/*
 424 * IR Rx & Tx Clock Register helpers
 425 */
 426static unsigned int txclk_tx_s_carrier(struct i2c_client *c,
 427				       unsigned int freq,
 428				       u16 *divider)
 429{
 430	*divider = carrier_freq_to_clock_divider(freq);
 431	cx25840_write4(c, CX25840_IR_TXCLK_REG, *divider);
 432	return clock_divider_to_carrier_freq(*divider);
 433}
 434
 435static unsigned int rxclk_rx_s_carrier(struct i2c_client *c,
 436				       unsigned int freq,
 437				       u16 *divider)
 438{
 439	*divider = carrier_freq_to_clock_divider(freq);
 440	cx25840_write4(c, CX25840_IR_RXCLK_REG, *divider);
 441	return clock_divider_to_carrier_freq(*divider);
 442}
 443
 444static u32 txclk_tx_s_max_pulse_width(struct i2c_client *c, u32 ns,
 445				      u16 *divider)
 446{
 447	u64 pulse_clocks;
 448
 449	if (ns > IR_MAX_DURATION)
 450		ns = IR_MAX_DURATION;
 451	pulse_clocks = ns_to_pulse_clocks(ns);
 452	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
 453	cx25840_write4(c, CX25840_IR_TXCLK_REG, *divider);
 454	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
 455}
 456
 457static u32 rxclk_rx_s_max_pulse_width(struct i2c_client *c, u32 ns,
 458				      u16 *divider)
 459{
 460	u64 pulse_clocks;
 461
 462	if (ns > IR_MAX_DURATION)
 463		ns = IR_MAX_DURATION;
 464	pulse_clocks = ns_to_pulse_clocks(ns);
 465	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
 466	cx25840_write4(c, CX25840_IR_RXCLK_REG, *divider);
 467	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
 468}
 469
 470/*
 471 * IR Tx Carrier Duty Cycle register helpers
 472 */
 473static unsigned int cduty_tx_s_duty_cycle(struct i2c_client *c,
 474					  unsigned int duty_cycle)
 475{
 476	u32 n;
 477	n = DIV_ROUND_CLOSEST(duty_cycle * 100, 625); /* 16ths of 100% */
 478	if (n != 0)
 479		n--;
 480	if (n > 15)
 481		n = 15;
 482	cx25840_write4(c, CX25840_IR_CDUTY_REG, n);
 483	return DIV_ROUND_CLOSEST((n + 1) * 100, 16);
 484}
 485
 486/*
 487 * IR Filter Register helpers
 488 */
 489static u32 filter_rx_s_min_width(struct i2c_client *c, u32 min_width_ns)
 490{
 491	u32 count = ns_to_lpf_count(min_width_ns);
 492	cx25840_write4(c, CX25840_IR_FILTR_REG, count);
 493	return lpf_count_to_ns(count);
 494}
 495
 496/*
 497 * IR IRQ Enable Register helpers
 498 */
 499static inline void irqenable_rx(struct v4l2_subdev *sd, u32 mask)
 500{
 501	struct cx25840_state *state = to_state(sd);
 502
 503	if (is_cx23885(state) || is_cx23887(state))
 504		mask ^= IRQEN_MSK;
 505	mask &= (IRQEN_RTE | IRQEN_ROE | IRQEN_RSE);
 506	cx25840_and_or4(state->c, CX25840_IR_IRQEN_REG,
 507			~(IRQEN_RTE | IRQEN_ROE | IRQEN_RSE), mask);
 508}
 509
 510static inline void irqenable_tx(struct v4l2_subdev *sd, u32 mask)
 511{
 512	struct cx25840_state *state = to_state(sd);
 513
 514	if (is_cx23885(state) || is_cx23887(state))
 515		mask ^= IRQEN_MSK;
 516	mask &= IRQEN_TSE;
 517	cx25840_and_or4(state->c, CX25840_IR_IRQEN_REG, ~IRQEN_TSE, mask);
 518}
 519
 520/*
 521 * V4L2 Subdevice IR Ops
 522 */
 523int cx25840_ir_irq_handler(struct v4l2_subdev *sd, u32 status, bool *handled)
 524{
 525	struct cx25840_state *state = to_state(sd);
 526	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 527	struct i2c_client *c = NULL;
 528	unsigned long flags;
 529
 530	union cx25840_ir_fifo_rec rx_data[FIFO_RX_DEPTH];
 531	unsigned int i, j, k;
 532	u32 events, v;
 533	int tsr, rsr, rto, ror, tse, rse, rte, roe, kror;
 534	u32 cntrl, irqen, stats;
 535
 536	*handled = false;
 537	if (ir_state == NULL)
 538		return -ENODEV;
 539
 540	c = ir_state->c;
 541
 542	/* Only support the IR controller for the CX2388[57] AV Core for now */
 543	if (!(is_cx23885(state) || is_cx23887(state)))
 544		return -ENODEV;
 545
 546	cntrl = cx25840_read4(c, CX25840_IR_CNTRL_REG);
 547	irqen = cx25840_read4(c, CX25840_IR_IRQEN_REG);
 548	if (is_cx23885(state) || is_cx23887(state))
 549		irqen ^= IRQEN_MSK;
 550	stats = cx25840_read4(c, CX25840_IR_STATS_REG);
 551
 552	tsr = stats & STATS_TSR; /* Tx FIFO Service Request */
 553	rsr = stats & STATS_RSR; /* Rx FIFO Service Request */
 554	rto = stats & STATS_RTO; /* Rx Pulse Width Timer Time Out */
 555	ror = stats & STATS_ROR; /* Rx FIFO Over Run */
 556
 557	tse = irqen & IRQEN_TSE; /* Tx FIFO Service Request IRQ Enable */
 558	rse = irqen & IRQEN_RSE; /* Rx FIFO Service Reuqest IRQ Enable */
 559	rte = irqen & IRQEN_RTE; /* Rx Pulse Width Timer Time Out IRQ Enable */
 560	roe = irqen & IRQEN_ROE; /* Rx FIFO Over Run IRQ Enable */
 561
 562	v4l2_dbg(2, ir_debug, sd, "IR IRQ Status:  %s %s %s %s %s %s\n",
 563		 tsr ? "tsr" : "   ", rsr ? "rsr" : "   ",
 564		 rto ? "rto" : "   ", ror ? "ror" : "   ",
 565		 stats & STATS_TBY ? "tby" : "   ",
 566		 stats & STATS_RBY ? "rby" : "   ");
 567
 568	v4l2_dbg(2, ir_debug, sd, "IR IRQ Enables: %s %s %s %s\n",
 569		 tse ? "tse" : "   ", rse ? "rse" : "   ",
 570		 rte ? "rte" : "   ", roe ? "roe" : "   ");
 571
 572	/*
 573	 * Transmitter interrupt service
 574	 */
 575	if (tse && tsr) {
 576		/*
 577		 * TODO:
 578		 * Check the watermark threshold setting
 579		 * Pull FIFO_TX_DEPTH or FIFO_TX_DEPTH/2 entries from tx_kfifo
 580		 * Push the data to the hardware FIFO.
 581		 * If there was nothing more to send in the tx_kfifo, disable
 582		 *	the TSR IRQ and notify the v4l2_device.
 583		 * If there was something in the tx_kfifo, check the tx_kfifo
 584		 *      level and notify the v4l2_device, if it is low.
 585		 */
 586		/* For now, inhibit TSR interrupt until Tx is implemented */
 587		irqenable_tx(sd, 0);
 588		events = V4L2_SUBDEV_IR_TX_FIFO_SERVICE_REQ;
 589		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_TX_NOTIFY, &events);
 590		*handled = true;
 591	}
 592
 593	/*
 594	 * Receiver interrupt service
 595	 */
 596	kror = 0;
 597	if ((rse && rsr) || (rte && rto)) {
 598		/*
 599		 * Receive data on RSR to clear the STATS_RSR.
 600		 * Receive data on RTO, since we may not have yet hit the RSR
 601		 * watermark when we receive the RTO.
 602		 */
 603		for (i = 0, v = FIFO_RX_NDV;
 604		     (v & FIFO_RX_NDV) && !kror; i = 0) {
 605			for (j = 0;
 606			     (v & FIFO_RX_NDV) && j < FIFO_RX_DEPTH; j++) {
 607				v = cx25840_read4(c, CX25840_IR_FIFO_REG);
 608				rx_data[i].hw_fifo_data = v & ~FIFO_RX_NDV;
 609				i++;
 610			}
 611			if (i == 0)
 612				break;
 613			j = i * sizeof(union cx25840_ir_fifo_rec);
 614			k = kfifo_in_locked(&ir_state->rx_kfifo,
 615					    (unsigned char *) rx_data, j,
 616					    &ir_state->rx_kfifo_lock);
 617			if (k != j)
 618				kror++; /* rx_kfifo over run */
 619		}
 620		*handled = true;
 621	}
 622
 623	events = 0;
 624	v = 0;
 625	if (kror) {
 626		events |= V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN;
 627		v4l2_err(sd, "IR receiver software FIFO overrun\n");
 628	}
 629	if (roe && ror) {
 630		/*
 631		 * The RX FIFO Enable (CNTRL_RFE) must be toggled to clear
 632		 * the Rx FIFO Over Run status (STATS_ROR)
 633		 */
 634		v |= CNTRL_RFE;
 635		events |= V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN;
 636		v4l2_err(sd, "IR receiver hardware FIFO overrun\n");
 637	}
 638	if (rte && rto) {
 639		/*
 640		 * The IR Receiver Enable (CNTRL_RXE) must be toggled to clear
 641		 * the Rx Pulse Width Timer Time Out (STATS_RTO)
 642		 */
 643		v |= CNTRL_RXE;
 644		events |= V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED;
 645	}
 646	if (v) {
 647		/* Clear STATS_ROR & STATS_RTO as needed by reseting hardware */
 648		cx25840_write4(c, CX25840_IR_CNTRL_REG, cntrl & ~v);
 649		cx25840_write4(c, CX25840_IR_CNTRL_REG, cntrl);
 650		*handled = true;
 651	}
 652	spin_lock_irqsave(&ir_state->rx_kfifo_lock, flags);
 653	if (kfifo_len(&ir_state->rx_kfifo) >= CX25840_IR_RX_KFIFO_SIZE / 2)
 654		events |= V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ;
 655	spin_unlock_irqrestore(&ir_state->rx_kfifo_lock, flags);
 656
 657	if (events)
 658		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_RX_NOTIFY, &events);
 659	return 0;
 660}
 661
 662/* Receiver */
 663static int cx25840_ir_rx_read(struct v4l2_subdev *sd, u8 *buf, size_t count,
 664			      ssize_t *num)
 665{
 666	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 667	bool invert;
 668	u16 divider;
 669	unsigned int i, n;
 670	union cx25840_ir_fifo_rec *p;
 671	unsigned u, v;
 672
 673	if (ir_state == NULL)
 674		return -ENODEV;
 675
 676	invert = (bool) atomic_read(&ir_state->rx_invert);
 677	divider = (u16) atomic_read(&ir_state->rxclk_divider);
 678
 679	n = count / sizeof(union cx25840_ir_fifo_rec)
 680		* sizeof(union cx25840_ir_fifo_rec);
 681	if (n == 0) {
 682		*num = 0;
 683		return 0;
 684	}
 685
 686	n = kfifo_out_locked(&ir_state->rx_kfifo, buf, n,
 687			     &ir_state->rx_kfifo_lock);
 688
 689	n /= sizeof(union cx25840_ir_fifo_rec);
 690	*num = n * sizeof(union cx25840_ir_fifo_rec);
 691
 692	for (p = (union cx25840_ir_fifo_rec *) buf, i = 0; i < n; p++, i++) {
 693
 694		if ((p->hw_fifo_data & FIFO_RXTX_RTO) == FIFO_RXTX_RTO) {
 695			/* Assume RTO was because of no IR light input */
 696			u = 0;
 697			v4l2_dbg(2, ir_debug, sd, "rx read: end of rx\n");
 698		} else {
 699			u = (p->hw_fifo_data & FIFO_RXTX_LVL) ? 1 : 0;
 700			if (invert)
 701				u = u ? 0 : 1;
 702		}
 703
 704		v = (unsigned) pulse_width_count_to_ns(
 705				  (u16) (p->hw_fifo_data & FIFO_RXTX), divider);
 706		if (v > IR_MAX_DURATION)
 707			v = IR_MAX_DURATION;
 708
 709		init_ir_raw_event(&p->ir_core_data);
 710		p->ir_core_data.pulse = u;
 711		p->ir_core_data.duration = v;
 712
 713		v4l2_dbg(2, ir_debug, sd, "rx read: %10u ns  %s\n",
 714			 v, u ? "mark" : "space");
 715	}
 716	return 0;
 717}
 718
 719static int cx25840_ir_rx_g_parameters(struct v4l2_subdev *sd,
 720				      struct v4l2_subdev_ir_parameters *p)
 721{
 722	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 723
 724	if (ir_state == NULL)
 725		return -ENODEV;
 726
 727	mutex_lock(&ir_state->rx_params_lock);
 728	memcpy(p, &ir_state->rx_params,
 729				      sizeof(struct v4l2_subdev_ir_parameters));
 730	mutex_unlock(&ir_state->rx_params_lock);
 731	return 0;
 732}
 733
 734static int cx25840_ir_rx_shutdown(struct v4l2_subdev *sd)
 735{
 736	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 737	struct i2c_client *c;
 738
 739	if (ir_state == NULL)
 740		return -ENODEV;
 741
 742	c = ir_state->c;
 743	mutex_lock(&ir_state->rx_params_lock);
 744
 745	/* Disable or slow down all IR Rx circuits and counters */
 746	irqenable_rx(sd, 0);
 747	control_rx_enable(c, false);
 748	control_rx_demodulation_enable(c, false);
 749	control_rx_s_edge_detection(c, CNTRL_EDG_NONE);
 750	filter_rx_s_min_width(c, 0);
 751	cx25840_write4(c, CX25840_IR_RXCLK_REG, RXCLK_RCD);
 752
 753	ir_state->rx_params.shutdown = true;
 754
 755	mutex_unlock(&ir_state->rx_params_lock);
 756	return 0;
 757}
 758
 759static int cx25840_ir_rx_s_parameters(struct v4l2_subdev *sd,
 760				      struct v4l2_subdev_ir_parameters *p)
 761{
 762	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 763	struct i2c_client *c;
 764	struct v4l2_subdev_ir_parameters *o;
 765	u16 rxclk_divider;
 766
 767	if (ir_state == NULL)
 768		return -ENODEV;
 769
 770	if (p->shutdown)
 771		return cx25840_ir_rx_shutdown(sd);
 772
 773	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
 774		return -ENOSYS;
 775
 776	c = ir_state->c;
 777	o = &ir_state->rx_params;
 778
 779	mutex_lock(&ir_state->rx_params_lock);
 780
 781	o->shutdown = p->shutdown;
 782
 783	p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
 784	o->mode = p->mode;
 785
 786	p->bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec);
 787	o->bytes_per_data_element = p->bytes_per_data_element;
 788
 789	/* Before we tweak the hardware, we have to disable the receiver */
 790	irqenable_rx(sd, 0);
 791	control_rx_enable(c, false);
 792
 793	control_rx_demodulation_enable(c, p->modulation);
 794	o->modulation = p->modulation;
 795
 796	if (p->modulation) {
 797		p->carrier_freq = rxclk_rx_s_carrier(c, p->carrier_freq,
 798						     &rxclk_divider);
 799
 800		o->carrier_freq = p->carrier_freq;
 801
 802		p->duty_cycle = 50;
 803		o->duty_cycle = p->duty_cycle;
 804
 805		control_rx_s_carrier_window(c, p->carrier_freq,
 806					    &p->carrier_range_lower,
 807					    &p->carrier_range_upper);
 808		o->carrier_range_lower = p->carrier_range_lower;
 809		o->carrier_range_upper = p->carrier_range_upper;
 810
 811		p->max_pulse_width =
 812			(u32) pulse_width_count_to_ns(FIFO_RXTX, rxclk_divider);
 813	} else {
 814		p->max_pulse_width =
 815			    rxclk_rx_s_max_pulse_width(c, p->max_pulse_width,
 816						       &rxclk_divider);
 817	}
 818	o->max_pulse_width = p->max_pulse_width;
 819	atomic_set(&ir_state->rxclk_divider, rxclk_divider);
 820
 821	p->noise_filter_min_width =
 822			    filter_rx_s_min_width(c, p->noise_filter_min_width);
 823	o->noise_filter_min_width = p->noise_filter_min_width;
 824
 825	p->resolution = clock_divider_to_resolution(rxclk_divider);
 826	o->resolution = p->resolution;
 827
 828	/* FIXME - make this dependent on resolution for better performance */
 829	control_rx_irq_watermark(c, RX_FIFO_HALF_FULL);
 830
 831	control_rx_s_edge_detection(c, CNTRL_EDG_BOTH);
 832
 833	o->invert_level = p->invert_level;
 834	atomic_set(&ir_state->rx_invert, p->invert_level);
 835
 836	o->interrupt_enable = p->interrupt_enable;
 837	o->enable = p->enable;
 838	if (p->enable) {
 839		unsigned long flags;
 840
 841		spin_lock_irqsave(&ir_state->rx_kfifo_lock, flags);
 842		kfifo_reset(&ir_state->rx_kfifo);
 843		spin_unlock_irqrestore(&ir_state->rx_kfifo_lock, flags);
 844		if (p->interrupt_enable)
 845			irqenable_rx(sd, IRQEN_RSE | IRQEN_RTE | IRQEN_ROE);
 846		control_rx_enable(c, p->enable);
 847	}
 848
 849	mutex_unlock(&ir_state->rx_params_lock);
 850	return 0;
 851}
 852
 853/* Transmitter */
 854static int cx25840_ir_tx_write(struct v4l2_subdev *sd, u8 *buf, size_t count,
 855			       ssize_t *num)
 856{
 857	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 858	struct i2c_client *c;
 859
 860	if (ir_state == NULL)
 861		return -ENODEV;
 862
 863	c = ir_state->c;
 864#if 0
 865	/*
 866	 * FIXME - the code below is an incomplete and untested sketch of what
 867	 * may need to be done.  The critical part is to get 4 (or 8) pulses
 868	 * from the tx_kfifo, or converted from ns to the proper units from the
 869	 * input, and push them off to the hardware Tx FIFO right away, if the
 870	 * HW TX fifo needs service.  The rest can be pushed to the tx_kfifo in
 871	 * a less critical timeframe.  Also watch out for overruning the
 872	 * tx_kfifo - don't let it happen and let the caller know not all his
 873	 * pulses were written.
 874	 */
 875	u32 *ns_pulse = (u32 *) buf;
 876	unsigned int n;
 877	u32 fifo_pulse[FIFO_TX_DEPTH];
 878	u32 mark;
 879
 880	/* Compute how much we can fit in the tx kfifo */
 881	n = CX25840_IR_TX_KFIFO_SIZE - kfifo_len(ir_state->tx_kfifo);
 882	n = min(n, (unsigned int) count);
 883	n /= sizeof(u32);
 884
 885	/* FIXME - turn on Tx Fifo service interrupt
 886	 * check hardware fifo level, and other stuff
 887	 */
 888	for (i = 0; i < n; ) {
 889		for (j = 0; j < FIFO_TX_DEPTH / 2 && i < n; j++) {
 890			mark = ns_pulse[i] & LEVEL_MASK;
 891			fifo_pulse[j] = ns_to_pulse_width_count(
 892					 ns_pulse[i] &
 893					       ~LEVEL_MASK,
 894					 ir_state->txclk_divider);
 895			if (mark)
 896				fifo_pulse[j] &= FIFO_RXTX_LVL;
 897			i++;
 898		}
 899		kfifo_put(ir_state->tx_kfifo, (u8 *) fifo_pulse,
 900							       j * sizeof(u32));
 901	}
 902	*num = n * sizeof(u32);
 903#else
 904	/* For now enable the Tx FIFO Service interrupt & pretend we did work */
 905	irqenable_tx(sd, IRQEN_TSE);
 906	*num = count;
 907#endif
 908	return 0;
 909}
 910
 911static int cx25840_ir_tx_g_parameters(struct v4l2_subdev *sd,
 912				      struct v4l2_subdev_ir_parameters *p)
 913{
 914	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 915
 916	if (ir_state == NULL)
 917		return -ENODEV;
 918
 919	mutex_lock(&ir_state->tx_params_lock);
 920	memcpy(p, &ir_state->tx_params,
 921				      sizeof(struct v4l2_subdev_ir_parameters));
 922	mutex_unlock(&ir_state->tx_params_lock);
 923	return 0;
 924}
 925
 926static int cx25840_ir_tx_shutdown(struct v4l2_subdev *sd)
 927{
 928	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 929	struct i2c_client *c;
 930
 931	if (ir_state == NULL)
 932		return -ENODEV;
 933
 934	c = ir_state->c;
 935	mutex_lock(&ir_state->tx_params_lock);
 936
 937	/* Disable or slow down all IR Tx circuits and counters */
 938	irqenable_tx(sd, 0);
 939	control_tx_enable(c, false);
 940	control_tx_modulation_enable(c, false);
 941	cx25840_write4(c, CX25840_IR_TXCLK_REG, TXCLK_TCD);
 942
 943	ir_state->tx_params.shutdown = true;
 944
 945	mutex_unlock(&ir_state->tx_params_lock);
 946	return 0;
 947}
 948
 949static int cx25840_ir_tx_s_parameters(struct v4l2_subdev *sd,
 950				      struct v4l2_subdev_ir_parameters *p)
 951{
 952	struct cx25840_ir_state *ir_state = to_ir_state(sd);
 953	struct i2c_client *c;
 954	struct v4l2_subdev_ir_parameters *o;
 955	u16 txclk_divider;
 956
 957	if (ir_state == NULL)
 958		return -ENODEV;
 959
 960	if (p->shutdown)
 961		return cx25840_ir_tx_shutdown(sd);
 962
 963	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
 964		return -ENOSYS;
 965
 966	c = ir_state->c;
 967	o = &ir_state->tx_params;
 968	mutex_lock(&ir_state->tx_params_lock);
 969
 970	o->shutdown = p->shutdown;
 971
 972	p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
 973	o->mode = p->mode;
 974
 975	p->bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec);
 976	o->bytes_per_data_element = p->bytes_per_data_element;
 977
 978	/* Before we tweak the hardware, we have to disable the transmitter */
 979	irqenable_tx(sd, 0);
 980	control_tx_enable(c, false);
 981
 982	control_tx_modulation_enable(c, p->modulation);
 983	o->modulation = p->modulation;
 984
 985	if (p->modulation) {
 986		p->carrier_freq = txclk_tx_s_carrier(c, p->carrier_freq,
 987						     &txclk_divider);
 988		o->carrier_freq = p->carrier_freq;
 989
 990		p->duty_cycle = cduty_tx_s_duty_cycle(c, p->duty_cycle);
 991		o->duty_cycle = p->duty_cycle;
 992
 993		p->max_pulse_width =
 994			(u32) pulse_width_count_to_ns(FIFO_RXTX, txclk_divider);
 995	} else {
 996		p->max_pulse_width =
 997			    txclk_tx_s_max_pulse_width(c, p->max_pulse_width,
 998						       &txclk_divider);
 999	}
1000	o->max_pulse_width = p->max_pulse_width;
1001	atomic_set(&ir_state->txclk_divider, txclk_divider);
1002
1003	p->resolution = clock_divider_to_resolution(txclk_divider);
1004	o->resolution = p->resolution;
1005
1006	/* FIXME - make this dependent on resolution for better performance */
1007	control_tx_irq_watermark(c, TX_FIFO_HALF_EMPTY);
1008
1009	control_tx_polarity_invert(c, p->invert_carrier_sense);
1010	o->invert_carrier_sense = p->invert_carrier_sense;
1011
1012	/*
1013	 * FIXME: we don't have hardware help for IO pin level inversion
1014	 * here like we have on the CX23888.
1015	 * Act on this with some mix of logical inversion of data levels,
1016	 * carrier polarity, and carrier duty cycle.
1017	 */
1018	o->invert_level = p->invert_level;
1019
1020	o->interrupt_enable = p->interrupt_enable;
1021	o->enable = p->enable;
1022	if (p->enable) {
1023		/* reset tx_fifo here */
1024		if (p->interrupt_enable)
1025			irqenable_tx(sd, IRQEN_TSE);
1026		control_tx_enable(c, p->enable);
1027	}
1028
1029	mutex_unlock(&ir_state->tx_params_lock);
1030	return 0;
1031}
1032
1033
1034/*
1035 * V4L2 Subdevice Core Ops support
1036 */
1037int cx25840_ir_log_status(struct v4l2_subdev *sd)
1038{
1039	struct cx25840_state *state = to_state(sd);
1040	struct i2c_client *c = state->c;
1041	char *s;
1042	int i, j;
1043	u32 cntrl, txclk, rxclk, cduty, stats, irqen, filtr;
1044
1045	/* The CX23888 chip doesn't have an IR controller on the A/V core */
1046	if (is_cx23888(state))
1047		return 0;
1048
1049	cntrl = cx25840_read4(c, CX25840_IR_CNTRL_REG);
1050	txclk = cx25840_read4(c, CX25840_IR_TXCLK_REG) & TXCLK_TCD;
1051	rxclk = cx25840_read4(c, CX25840_IR_RXCLK_REG) & RXCLK_RCD;
1052	cduty = cx25840_read4(c, CX25840_IR_CDUTY_REG) & CDUTY_CDC;
1053	stats = cx25840_read4(c, CX25840_IR_STATS_REG);
1054	irqen = cx25840_read4(c, CX25840_IR_IRQEN_REG);
1055	if (is_cx23885(state) || is_cx23887(state))
1056		irqen ^= IRQEN_MSK;
1057	filtr = cx25840_read4(c, CX25840_IR_FILTR_REG) & FILTR_LPF;
1058
1059	v4l2_info(sd, "IR Receiver:\n");
1060	v4l2_info(sd, "\tEnabled:                           %s\n",
1061		  cntrl & CNTRL_RXE ? "yes" : "no");
1062	v4l2_info(sd, "\tDemodulation from a carrier:       %s\n",
1063		  cntrl & CNTRL_DMD ? "enabled" : "disabled");
1064	v4l2_info(sd, "\tFIFO:                              %s\n",
1065		  cntrl & CNTRL_RFE ? "enabled" : "disabled");
1066	switch (cntrl & CNTRL_EDG) {
1067	case CNTRL_EDG_NONE:
1068		s = "disabled";
1069		break;
1070	case CNTRL_EDG_FALL:
1071		s = "falling edge";
1072		break;
1073	case CNTRL_EDG_RISE:
1074		s = "rising edge";
1075		break;
1076	case CNTRL_EDG_BOTH:
1077		s = "rising & falling edges";
1078		break;
1079	default:
1080		s = "??? edge";
1081		break;
1082	}
1083	v4l2_info(sd, "\tPulse timers' start/stop trigger:  %s\n", s);
1084	v4l2_info(sd, "\tFIFO data on pulse timer overflow: %s\n",
1085		  cntrl & CNTRL_R ? "not loaded" : "overflow marker");
1086	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1087		  cntrl & CNTRL_RIC ? "not empty" : "half full or greater");
1088	v4l2_info(sd, "\tLoopback mode:                     %s\n",
1089		  cntrl & CNTRL_LBM ? "loopback active" : "normal receive");
1090	if (cntrl & CNTRL_DMD) {
1091		v4l2_info(sd, "\tExpected carrier (16 clocks):      %u Hz\n",
1092			  clock_divider_to_carrier_freq(rxclk));
1093		switch (cntrl & CNTRL_WIN) {
1094		case CNTRL_WIN_3_3:
1095			i = 3;
1096			j = 3;
1097			break;
1098		case CNTRL_WIN_4_3:
1099			i = 4;
1100			j = 3;
1101			break;
1102		case CNTRL_WIN_3_4:
1103			i = 3;
1104			j = 4;
1105			break;
1106		case CNTRL_WIN_4_4:
1107			i = 4;
1108			j = 4;
1109			break;
1110		default:
1111			i = 0;
1112			j = 0;
1113			break;
1114		}
1115		v4l2_info(sd, "\tNext carrier edge window:          16 clocks "
1116			  "-%1d/+%1d, %u to %u Hz\n", i, j,
1117			  clock_divider_to_freq(rxclk, 16 + j),
1118			  clock_divider_to_freq(rxclk, 16 - i));
1119	}
1120	v4l2_info(sd, "\tMax measurable pulse width:        %u us, %llu ns\n",
1121		  pulse_width_count_to_us(FIFO_RXTX, rxclk),
1122		  pulse_width_count_to_ns(FIFO_RXTX, rxclk));
1123	v4l2_info(sd, "\tLow pass filter:                   %s\n",
1124		  filtr ? "enabled" : "disabled");
1125	if (filtr)
1126		v4l2_info(sd, "\tMin acceptable pulse width (LPF):  %u us, "
1127			  "%u ns\n",
1128			  lpf_count_to_us(filtr),
1129			  lpf_count_to_ns(filtr));
1130	v4l2_info(sd, "\tPulse width timer timed-out:       %s\n",
1131		  stats & STATS_RTO ? "yes" : "no");
1132	v4l2_info(sd, "\tPulse width timer time-out intr:   %s\n",
1133		  irqen & IRQEN_RTE ? "enabled" : "disabled");
1134	v4l2_info(sd, "\tFIFO overrun:                      %s\n",
1135		  stats & STATS_ROR ? "yes" : "no");
1136	v4l2_info(sd, "\tFIFO overrun interrupt:            %s\n",
1137		  irqen & IRQEN_ROE ? "enabled" : "disabled");
1138	v4l2_info(sd, "\tBusy:                              %s\n",
1139		  stats & STATS_RBY ? "yes" : "no");
1140	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1141		  stats & STATS_RSR ? "yes" : "no");
1142	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1143		  irqen & IRQEN_RSE ? "enabled" : "disabled");
1144
1145	v4l2_info(sd, "IR Transmitter:\n");
1146	v4l2_info(sd, "\tEnabled:                           %s\n",
1147		  cntrl & CNTRL_TXE ? "yes" : "no");
1148	v4l2_info(sd, "\tModulation onto a carrier:         %s\n",
1149		  cntrl & CNTRL_MOD ? "enabled" : "disabled");
1150	v4l2_info(sd, "\tFIFO:                              %s\n",
1151		  cntrl & CNTRL_TFE ? "enabled" : "disabled");
1152	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1153		  cntrl & CNTRL_TIC ? "not empty" : "half full or less");
1154	v4l2_info(sd, "\tCarrier polarity:                  %s\n",
1155		  cntrl & CNTRL_CPL ? "space:burst mark:noburst"
1156				    : "space:noburst mark:burst");
1157	if (cntrl & CNTRL_MOD) {
1158		v4l2_info(sd, "\tCarrier (16 clocks):               %u Hz\n",
1159			  clock_divider_to_carrier_freq(txclk));
1160		v4l2_info(sd, "\tCarrier duty cycle:                %2u/16\n",
1161			  cduty + 1);
1162	}
1163	v4l2_info(sd, "\tMax pulse width:                   %u us, %llu ns\n",
1164		  pulse_width_count_to_us(FIFO_RXTX, txclk),
1165		  pulse_width_count_to_ns(FIFO_RXTX, txclk));
1166	v4l2_info(sd, "\tBusy:                              %s\n",
1167		  stats & STATS_TBY ? "yes" : "no");
1168	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1169		  stats & STATS_TSR ? "yes" : "no");
1170	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1171		  irqen & IRQEN_TSE ? "enabled" : "disabled");
1172
1173	return 0;
1174}
1175
1176
1177const struct v4l2_subdev_ir_ops cx25840_ir_ops = {
1178	.rx_read = cx25840_ir_rx_read,
1179	.rx_g_parameters = cx25840_ir_rx_g_parameters,
1180	.rx_s_parameters = cx25840_ir_rx_s_parameters,
1181
1182	.tx_write = cx25840_ir_tx_write,
1183	.tx_g_parameters = cx25840_ir_tx_g_parameters,
1184	.tx_s_parameters = cx25840_ir_tx_s_parameters,
1185};
1186
1187
1188static const struct v4l2_subdev_ir_parameters default_rx_params = {
1189	.bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec),
1190	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1191
1192	.enable = false,
1193	.interrupt_enable = false,
1194	.shutdown = true,
1195
1196	.modulation = true,
1197	.carrier_freq = 36000, /* 36 kHz - RC-5, and RC-6 carrier */
1198
1199	/* RC-5: 666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
1200	/* RC-6: 333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
1201	.noise_filter_min_width = 333333, /* ns */
1202	.carrier_range_lower = 35000,
1203	.carrier_range_upper = 37000,
1204	.invert_level = false,
1205};
1206
1207static const struct v4l2_subdev_ir_parameters default_tx_params = {
1208	.bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec),
1209	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1210
1211	.enable = false,
1212	.interrupt_enable = false,
1213	.shutdown = true,
1214
1215	.modulation = true,
1216	.carrier_freq = 36000, /* 36 kHz - RC-5 carrier */
1217	.duty_cycle = 25,      /* 25 %   - RC-5 carrier */
1218	.invert_level = false,
1219	.invert_carrier_sense = false,
1220};
1221
1222int cx25840_ir_probe(struct v4l2_subdev *sd)
1223{
1224	struct cx25840_state *state = to_state(sd);
1225	struct cx25840_ir_state *ir_state;
1226	struct v4l2_subdev_ir_parameters default_params;
1227
1228	/* Only init the IR controller for the CX2388[57] AV Core for now */
1229	if (!(is_cx23885(state) || is_cx23887(state)))
1230		return 0;
1231
1232	ir_state = kzalloc(sizeof(struct cx25840_ir_state), GFP_KERNEL);
1233	if (ir_state == NULL)
1234		return -ENOMEM;
1235
1236	spin_lock_init(&ir_state->rx_kfifo_lock);
1237	if (kfifo_alloc(&ir_state->rx_kfifo,
1238			CX25840_IR_RX_KFIFO_SIZE, GFP_KERNEL)) {
1239		kfree(ir_state);
1240		return -ENOMEM;
1241	}
1242
1243	ir_state->c = state->c;
1244	state->ir_state = ir_state;
1245
1246	/* Ensure no interrupts arrive yet */
1247	if (is_cx23885(state) || is_cx23887(state))
1248		cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, IRQEN_MSK);
1249	else
1250		cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, 0);
1251
1252	mutex_init(&ir_state->rx_params_lock);
1253	memcpy(&default_params, &default_rx_params,
1254		       sizeof(struct v4l2_subdev_ir_parameters));
1255	v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);
1256
1257	mutex_init(&ir_state->tx_params_lock);
1258	memcpy(&default_params, &default_tx_params,
1259		       sizeof(struct v4l2_subdev_ir_parameters));
1260	v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
1261
1262	return 0;
1263}
1264
1265int cx25840_ir_remove(struct v4l2_subdev *sd)
1266{
1267	struct cx25840_state *state = to_state(sd);
1268	struct cx25840_ir_state *ir_state = to_ir_state(sd);
1269
1270	if (ir_state == NULL)
1271		return -ENODEV;
1272
1273	cx25840_ir_rx_shutdown(sd);
1274	cx25840_ir_tx_shutdown(sd);
1275
1276	kfifo_free(&ir_state->rx_kfifo);
1277	kfree(ir_state);
1278	state->ir_state = NULL;
1279	return 0;
1280}