xref: /linux/drivers/media/i2c/cx25840/cx25840-ir.c (revision e9f0878c4b2004ac19581274c1ae4c61ae3ca70e)
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 
19 #include <linux/slab.h>
20 #include <linux/kfifo.h>
21 #include <linux/module.h>
22 #include <media/drv-intf/cx25840.h>
23 #include <media/rc-core.h>
24 
25 #include "cx25840-core.h"
26 
27 static unsigned int ir_debug;
28 module_param(ir_debug, int, 0644);
29 MODULE_PARM_DESC(ir_debug, "enable integrated IR debug messages");
30 
31 #define CX25840_IR_REG_BASE	0x200
32 
33 #define CX25840_IR_CNTRL_REG	0x200
34 #define CNTRL_WIN_3_3	0x00000000
35 #define CNTRL_WIN_4_3	0x00000001
36 #define CNTRL_WIN_3_4	0x00000002
37 #define CNTRL_WIN_4_4	0x00000003
38 #define CNTRL_WIN	0x00000003
39 #define CNTRL_EDG_NONE	0x00000000
40 #define CNTRL_EDG_FALL	0x00000004
41 #define CNTRL_EDG_RISE	0x00000008
42 #define CNTRL_EDG_BOTH	0x0000000C
43 #define CNTRL_EDG	0x0000000C
44 #define CNTRL_DMD	0x00000010
45 #define CNTRL_MOD	0x00000020
46 #define CNTRL_RFE	0x00000040
47 #define CNTRL_TFE	0x00000080
48 #define CNTRL_RXE	0x00000100
49 #define CNTRL_TXE	0x00000200
50 #define CNTRL_RIC	0x00000400
51 #define CNTRL_TIC	0x00000800
52 #define CNTRL_CPL	0x00001000
53 #define CNTRL_LBM	0x00002000
54 #define CNTRL_R		0x00004000
55 
56 #define CX25840_IR_TXCLK_REG	0x204
57 #define TXCLK_TCD	0x0000FFFF
58 
59 #define CX25840_IR_RXCLK_REG	0x208
60 #define RXCLK_RCD	0x0000FFFF
61 
62 #define CX25840_IR_CDUTY_REG	0x20C
63 #define CDUTY_CDC	0x0000000F
64 
65 #define CX25840_IR_STATS_REG	0x210
66 #define STATS_RTO	0x00000001
67 #define STATS_ROR	0x00000002
68 #define STATS_RBY	0x00000004
69 #define STATS_TBY	0x00000008
70 #define STATS_RSR	0x00000010
71 #define STATS_TSR	0x00000020
72 
73 #define CX25840_IR_IRQEN_REG	0x214
74 #define IRQEN_RTE	0x00000001
75 #define IRQEN_ROE	0x00000002
76 #define IRQEN_RSE	0x00000010
77 #define IRQEN_TSE	0x00000020
78 #define IRQEN_MSK	0x00000033
79 
80 #define CX25840_IR_FILTR_REG	0x218
81 #define FILTR_LPF	0x0000FFFF
82 
83 #define CX25840_IR_FIFO_REG	0x23C
84 #define FIFO_RXTX	0x0000FFFF
85 #define FIFO_RXTX_LVL	0x00010000
86 #define FIFO_RXTX_RTO	0x0001FFFF
87 #define FIFO_RX_NDV	0x00020000
88 #define FIFO_RX_DEPTH	8
89 #define FIFO_TX_DEPTH	8
90 
91 #define CX25840_VIDCLK_FREQ	108000000 /* 108 MHz, BT.656 */
92 #define CX25840_IR_REFCLK_FREQ	(CX25840_VIDCLK_FREQ / 2)
93 
94 /*
95  * We use this union internally for convenience, but callers to tx_write
96  * and rx_read will be expecting records of type struct ir_raw_event.
97  * Always ensure the size of this union is dictated by struct ir_raw_event.
98  */
99 union cx25840_ir_fifo_rec {
100 	u32 hw_fifo_data;
101 	struct ir_raw_event ir_core_data;
102 };
103 
104 #define CX25840_IR_RX_KFIFO_SIZE    (256 * sizeof(union cx25840_ir_fifo_rec))
105 #define CX25840_IR_TX_KFIFO_SIZE    (256 * sizeof(union cx25840_ir_fifo_rec))
106 
107 struct cx25840_ir_state {
108 	struct i2c_client *c;
109 
110 	struct v4l2_subdev_ir_parameters rx_params;
111 	struct mutex rx_params_lock; /* protects Rx parameter settings cache */
112 	atomic_t rxclk_divider;
113 	atomic_t rx_invert;
114 
115 	struct kfifo rx_kfifo;
116 	spinlock_t rx_kfifo_lock; /* protect Rx data kfifo */
117 
118 	struct v4l2_subdev_ir_parameters tx_params;
119 	struct mutex tx_params_lock; /* protects Tx parameter settings cache */
120 	atomic_t txclk_divider;
121 };
122 
123 static inline struct cx25840_ir_state *to_ir_state(struct v4l2_subdev *sd)
124 {
125 	struct cx25840_state *state = to_state(sd);
126 	return state ? state->ir_state : NULL;
127 }
128 
129 
130 /*
131  * Rx and Tx Clock Divider register computations
132  *
133  * Note the largest clock divider value of 0xffff corresponds to:
134  *	(0xffff + 1) * 1000 / 108/2 MHz = 1,213,629.629... ns
135  * which fits in 21 bits, so we'll use unsigned int for time arguments.
136  */
137 static inline u16 count_to_clock_divider(unsigned int d)
138 {
139 	if (d > RXCLK_RCD + 1)
140 		d = RXCLK_RCD;
141 	else if (d < 2)
142 		d = 1;
143 	else
144 		d--;
145 	return (u16) d;
146 }
147 
148 static inline u16 ns_to_clock_divider(unsigned int ns)
149 {
150 	return count_to_clock_divider(
151 		DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ / 1000000 * ns, 1000));
152 }
153 
154 static inline unsigned int clock_divider_to_ns(unsigned int divider)
155 {
156 	/* Period of the Rx or Tx clock in ns */
157 	return DIV_ROUND_CLOSEST((divider + 1) * 1000,
158 				 CX25840_IR_REFCLK_FREQ / 1000000);
159 }
160 
161 static inline u16 carrier_freq_to_clock_divider(unsigned int freq)
162 {
163 	return count_to_clock_divider(
164 			  DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, freq * 16));
165 }
166 
167 static inline unsigned int clock_divider_to_carrier_freq(unsigned int divider)
168 {
169 	return DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, (divider + 1) * 16);
170 }
171 
172 static inline u16 freq_to_clock_divider(unsigned int freq,
173 					unsigned int rollovers)
174 {
175 	return count_to_clock_divider(
176 		   DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, freq * rollovers));
177 }
178 
179 static inline unsigned int clock_divider_to_freq(unsigned int divider,
180 						 unsigned int rollovers)
181 {
182 	return DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ,
183 				 (divider + 1) * rollovers);
184 }
185 
186 /*
187  * Low Pass Filter register calculations
188  *
189  * Note the largest count value of 0xffff corresponds to:
190  *	0xffff * 1000 / 108/2 MHz = 1,213,611.11... ns
191  * which fits in 21 bits, so we'll use unsigned int for time arguments.
192  */
193 static inline u16 count_to_lpf_count(unsigned int d)
194 {
195 	if (d > FILTR_LPF)
196 		d = FILTR_LPF;
197 	else if (d < 4)
198 		d = 0;
199 	return (u16) d;
200 }
201 
202 static inline u16 ns_to_lpf_count(unsigned int ns)
203 {
204 	return count_to_lpf_count(
205 		DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ / 1000000 * ns, 1000));
206 }
207 
208 static inline unsigned int lpf_count_to_ns(unsigned int count)
209 {
210 	/* Duration of the Low Pass Filter rejection window in ns */
211 	return DIV_ROUND_CLOSEST(count * 1000,
212 				 CX25840_IR_REFCLK_FREQ / 1000000);
213 }
214 
215 static inline unsigned int lpf_count_to_us(unsigned int count)
216 {
217 	/* Duration of the Low Pass Filter rejection window in us */
218 	return DIV_ROUND_CLOSEST(count, CX25840_IR_REFCLK_FREQ / 1000000);
219 }
220 
221 /*
222  * FIFO register pulse width count computations
223  */
224 static u32 clock_divider_to_resolution(u16 divider)
225 {
226 	/*
227 	 * Resolution is the duration of 1 tick of the readable portion of
228 	 * of the pulse width counter as read from the FIFO.  The two lsb's are
229 	 * not readable, hence the << 2.  This function returns ns.
230 	 */
231 	return DIV_ROUND_CLOSEST((1 << 2)  * ((u32) divider + 1) * 1000,
232 				 CX25840_IR_REFCLK_FREQ / 1000000);
233 }
234 
235 static u64 pulse_width_count_to_ns(u16 count, u16 divider)
236 {
237 	u64 n;
238 	u32 rem;
239 
240 	/*
241 	 * The 2 lsb's of the pulse width timer count are not readable, hence
242 	 * the (count << 2) | 0x3
243 	 */
244 	n = (((u64) count << 2) | 0x3) * (divider + 1) * 1000; /* millicycles */
245 	rem = do_div(n, CX25840_IR_REFCLK_FREQ / 1000000);     /* / MHz => ns */
246 	if (rem >= CX25840_IR_REFCLK_FREQ / 1000000 / 2)
247 		n++;
248 	return n;
249 }
250 
251 #if 0
252 /* Keep as we will need this for Transmit functionality */
253 static u16 ns_to_pulse_width_count(u32 ns, u16 divider)
254 {
255 	u64 n;
256 	u32 d;
257 	u32 rem;
258 
259 	/*
260 	 * The 2 lsb's of the pulse width timer count are not accessible, hence
261 	 * the (1 << 2)
262 	 */
263 	n = ((u64) ns) * CX25840_IR_REFCLK_FREQ / 1000000; /* millicycles */
264 	d = (1 << 2) * ((u32) divider + 1) * 1000; /* millicycles/count */
265 	rem = do_div(n, d);
266 	if (rem >= d / 2)
267 		n++;
268 
269 	if (n > FIFO_RXTX)
270 		n = FIFO_RXTX;
271 	else if (n == 0)
272 		n = 1;
273 	return (u16) n;
274 }
275 
276 #endif
277 static unsigned int pulse_width_count_to_us(u16 count, u16 divider)
278 {
279 	u64 n;
280 	u32 rem;
281 
282 	/*
283 	 * The 2 lsb's of the pulse width timer count are not readable, hence
284 	 * the (count << 2) | 0x3
285 	 */
286 	n = (((u64) count << 2) | 0x3) * (divider + 1);    /* cycles      */
287 	rem = do_div(n, CX25840_IR_REFCLK_FREQ / 1000000); /* / MHz => us */
288 	if (rem >= CX25840_IR_REFCLK_FREQ / 1000000 / 2)
289 		n++;
290 	return (unsigned int) n;
291 }
292 
293 /*
294  * Pulse Clocks computations: Combined Pulse Width Count & Rx Clock Counts
295  *
296  * The total pulse clock count is an 18 bit pulse width timer count as the most
297  * significant part and (up to) 16 bit clock divider count as a modulus.
298  * When the Rx clock divider ticks down to 0, it increments the 18 bit pulse
299  * width timer count's least significant bit.
300  */
301 static u64 ns_to_pulse_clocks(u32 ns)
302 {
303 	u64 clocks;
304 	u32 rem;
305 	clocks = CX25840_IR_REFCLK_FREQ / 1000000 * (u64) ns; /* millicycles  */
306 	rem = do_div(clocks, 1000);                         /* /1000 = cycles */
307 	if (rem >= 1000 / 2)
308 		clocks++;
309 	return clocks;
310 }
311 
312 static u16 pulse_clocks_to_clock_divider(u64 count)
313 {
314 	do_div(count, (FIFO_RXTX << 2) | 0x3);
315 
316 	/* net result needs to be rounded down and decremented by 1 */
317 	if (count > RXCLK_RCD + 1)
318 		count = RXCLK_RCD;
319 	else if (count < 2)
320 		count = 1;
321 	else
322 		count--;
323 	return (u16) count;
324 }
325 
326 /*
327  * IR Control Register helpers
328  */
329 enum tx_fifo_watermark {
330 	TX_FIFO_HALF_EMPTY = 0,
331 	TX_FIFO_EMPTY      = CNTRL_TIC,
332 };
333 
334 enum rx_fifo_watermark {
335 	RX_FIFO_HALF_FULL = 0,
336 	RX_FIFO_NOT_EMPTY = CNTRL_RIC,
337 };
338 
339 static inline void control_tx_irq_watermark(struct i2c_client *c,
340 					    enum tx_fifo_watermark level)
341 {
342 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_TIC, level);
343 }
344 
345 static inline void control_rx_irq_watermark(struct i2c_client *c,
346 					    enum rx_fifo_watermark level)
347 {
348 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_RIC, level);
349 }
350 
351 static inline void control_tx_enable(struct i2c_client *c, bool enable)
352 {
353 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~(CNTRL_TXE | CNTRL_TFE),
354 			enable ? (CNTRL_TXE | CNTRL_TFE) : 0);
355 }
356 
357 static inline void control_rx_enable(struct i2c_client *c, bool enable)
358 {
359 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~(CNTRL_RXE | CNTRL_RFE),
360 			enable ? (CNTRL_RXE | CNTRL_RFE) : 0);
361 }
362 
363 static inline void control_tx_modulation_enable(struct i2c_client *c,
364 						bool enable)
365 {
366 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_MOD,
367 			enable ? CNTRL_MOD : 0);
368 }
369 
370 static inline void control_rx_demodulation_enable(struct i2c_client *c,
371 						  bool enable)
372 {
373 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_DMD,
374 			enable ? CNTRL_DMD : 0);
375 }
376 
377 static inline void control_rx_s_edge_detection(struct i2c_client *c,
378 					       u32 edge_types)
379 {
380 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_EDG_BOTH,
381 			edge_types & CNTRL_EDG_BOTH);
382 }
383 
384 static void control_rx_s_carrier_window(struct i2c_client *c,
385 					unsigned int carrier,
386 					unsigned int *carrier_range_low,
387 					unsigned int *carrier_range_high)
388 {
389 	u32 v;
390 	unsigned int c16 = carrier * 16;
391 
392 	if (*carrier_range_low < DIV_ROUND_CLOSEST(c16, 16 + 3)) {
393 		v = CNTRL_WIN_3_4;
394 		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 4);
395 	} else {
396 		v = CNTRL_WIN_3_3;
397 		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 3);
398 	}
399 
400 	if (*carrier_range_high > DIV_ROUND_CLOSEST(c16, 16 - 3)) {
401 		v |= CNTRL_WIN_4_3;
402 		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 4);
403 	} else {
404 		v |= CNTRL_WIN_3_3;
405 		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 3);
406 	}
407 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_WIN, v);
408 }
409 
410 static inline void control_tx_polarity_invert(struct i2c_client *c,
411 					      bool invert)
412 {
413 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_CPL,
414 			invert ? CNTRL_CPL : 0);
415 }
416 
417 /*
418  * IR Rx & Tx Clock Register helpers
419  */
420 static unsigned int txclk_tx_s_carrier(struct i2c_client *c,
421 				       unsigned int freq,
422 				       u16 *divider)
423 {
424 	*divider = carrier_freq_to_clock_divider(freq);
425 	cx25840_write4(c, CX25840_IR_TXCLK_REG, *divider);
426 	return clock_divider_to_carrier_freq(*divider);
427 }
428 
429 static unsigned int rxclk_rx_s_carrier(struct i2c_client *c,
430 				       unsigned int freq,
431 				       u16 *divider)
432 {
433 	*divider = carrier_freq_to_clock_divider(freq);
434 	cx25840_write4(c, CX25840_IR_RXCLK_REG, *divider);
435 	return clock_divider_to_carrier_freq(*divider);
436 }
437 
438 static u32 txclk_tx_s_max_pulse_width(struct i2c_client *c, u32 ns,
439 				      u16 *divider)
440 {
441 	u64 pulse_clocks;
442 
443 	if (ns > IR_MAX_DURATION)
444 		ns = IR_MAX_DURATION;
445 	pulse_clocks = ns_to_pulse_clocks(ns);
446 	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
447 	cx25840_write4(c, CX25840_IR_TXCLK_REG, *divider);
448 	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
449 }
450 
451 static u32 rxclk_rx_s_max_pulse_width(struct i2c_client *c, u32 ns,
452 				      u16 *divider)
453 {
454 	u64 pulse_clocks;
455 
456 	if (ns > IR_MAX_DURATION)
457 		ns = IR_MAX_DURATION;
458 	pulse_clocks = ns_to_pulse_clocks(ns);
459 	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
460 	cx25840_write4(c, CX25840_IR_RXCLK_REG, *divider);
461 	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
462 }
463 
464 /*
465  * IR Tx Carrier Duty Cycle register helpers
466  */
467 static unsigned int cduty_tx_s_duty_cycle(struct i2c_client *c,
468 					  unsigned int duty_cycle)
469 {
470 	u32 n;
471 	n = DIV_ROUND_CLOSEST(duty_cycle * 100, 625); /* 16ths of 100% */
472 	if (n != 0)
473 		n--;
474 	if (n > 15)
475 		n = 15;
476 	cx25840_write4(c, CX25840_IR_CDUTY_REG, n);
477 	return DIV_ROUND_CLOSEST((n + 1) * 100, 16);
478 }
479 
480 /*
481  * IR Filter Register helpers
482  */
483 static u32 filter_rx_s_min_width(struct i2c_client *c, u32 min_width_ns)
484 {
485 	u32 count = ns_to_lpf_count(min_width_ns);
486 	cx25840_write4(c, CX25840_IR_FILTR_REG, count);
487 	return lpf_count_to_ns(count);
488 }
489 
490 /*
491  * IR IRQ Enable Register helpers
492  */
493 static inline void irqenable_rx(struct v4l2_subdev *sd, u32 mask)
494 {
495 	struct cx25840_state *state = to_state(sd);
496 
497 	if (is_cx23885(state) || is_cx23887(state))
498 		mask ^= IRQEN_MSK;
499 	mask &= (IRQEN_RTE | IRQEN_ROE | IRQEN_RSE);
500 	cx25840_and_or4(state->c, CX25840_IR_IRQEN_REG,
501 			~(IRQEN_RTE | IRQEN_ROE | IRQEN_RSE), mask);
502 }
503 
504 static inline void irqenable_tx(struct v4l2_subdev *sd, u32 mask)
505 {
506 	struct cx25840_state *state = to_state(sd);
507 
508 	if (is_cx23885(state) || is_cx23887(state))
509 		mask ^= IRQEN_MSK;
510 	mask &= IRQEN_TSE;
511 	cx25840_and_or4(state->c, CX25840_IR_IRQEN_REG, ~IRQEN_TSE, mask);
512 }
513 
514 /*
515  * V4L2 Subdevice IR Ops
516  */
517 int cx25840_ir_irq_handler(struct v4l2_subdev *sd, u32 status, bool *handled)
518 {
519 	struct cx25840_state *state = to_state(sd);
520 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
521 	struct i2c_client *c = NULL;
522 	unsigned long flags;
523 
524 	union cx25840_ir_fifo_rec rx_data[FIFO_RX_DEPTH];
525 	unsigned int i, j, k;
526 	u32 events, v;
527 	int tsr, rsr, rto, ror, tse, rse, rte, roe, kror;
528 	u32 cntrl, irqen, stats;
529 
530 	*handled = false;
531 	if (ir_state == NULL)
532 		return -ENODEV;
533 
534 	c = ir_state->c;
535 
536 	/* Only support the IR controller for the CX2388[57] AV Core for now */
537 	if (!(is_cx23885(state) || is_cx23887(state)))
538 		return -ENODEV;
539 
540 	cntrl = cx25840_read4(c, CX25840_IR_CNTRL_REG);
541 	irqen = cx25840_read4(c, CX25840_IR_IRQEN_REG);
542 	if (is_cx23885(state) || is_cx23887(state))
543 		irqen ^= IRQEN_MSK;
544 	stats = cx25840_read4(c, CX25840_IR_STATS_REG);
545 
546 	tsr = stats & STATS_TSR; /* Tx FIFO Service Request */
547 	rsr = stats & STATS_RSR; /* Rx FIFO Service Request */
548 	rto = stats & STATS_RTO; /* Rx Pulse Width Timer Time Out */
549 	ror = stats & STATS_ROR; /* Rx FIFO Over Run */
550 
551 	tse = irqen & IRQEN_TSE; /* Tx FIFO Service Request IRQ Enable */
552 	rse = irqen & IRQEN_RSE; /* Rx FIFO Service Reuqest IRQ Enable */
553 	rte = irqen & IRQEN_RTE; /* Rx Pulse Width Timer Time Out IRQ Enable */
554 	roe = irqen & IRQEN_ROE; /* Rx FIFO Over Run IRQ Enable */
555 
556 	v4l2_dbg(2, ir_debug, sd, "IR IRQ Status:  %s %s %s %s %s %s\n",
557 		 tsr ? "tsr" : "   ", rsr ? "rsr" : "   ",
558 		 rto ? "rto" : "   ", ror ? "ror" : "   ",
559 		 stats & STATS_TBY ? "tby" : "   ",
560 		 stats & STATS_RBY ? "rby" : "   ");
561 
562 	v4l2_dbg(2, ir_debug, sd, "IR IRQ Enables: %s %s %s %s\n",
563 		 tse ? "tse" : "   ", rse ? "rse" : "   ",
564 		 rte ? "rte" : "   ", roe ? "roe" : "   ");
565 
566 	/*
567 	 * Transmitter interrupt service
568 	 */
569 	if (tse && tsr) {
570 		/*
571 		 * TODO:
572 		 * Check the watermark threshold setting
573 		 * Pull FIFO_TX_DEPTH or FIFO_TX_DEPTH/2 entries from tx_kfifo
574 		 * Push the data to the hardware FIFO.
575 		 * If there was nothing more to send in the tx_kfifo, disable
576 		 *	the TSR IRQ and notify the v4l2_device.
577 		 * If there was something in the tx_kfifo, check the tx_kfifo
578 		 *      level and notify the v4l2_device, if it is low.
579 		 */
580 		/* For now, inhibit TSR interrupt until Tx is implemented */
581 		irqenable_tx(sd, 0);
582 		events = V4L2_SUBDEV_IR_TX_FIFO_SERVICE_REQ;
583 		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_TX_NOTIFY, &events);
584 		*handled = true;
585 	}
586 
587 	/*
588 	 * Receiver interrupt service
589 	 */
590 	kror = 0;
591 	if ((rse && rsr) || (rte && rto)) {
592 		/*
593 		 * Receive data on RSR to clear the STATS_RSR.
594 		 * Receive data on RTO, since we may not have yet hit the RSR
595 		 * watermark when we receive the RTO.
596 		 */
597 		for (i = 0, v = FIFO_RX_NDV;
598 		     (v & FIFO_RX_NDV) && !kror; i = 0) {
599 			for (j = 0;
600 			     (v & FIFO_RX_NDV) && j < FIFO_RX_DEPTH; j++) {
601 				v = cx25840_read4(c, CX25840_IR_FIFO_REG);
602 				rx_data[i].hw_fifo_data = v & ~FIFO_RX_NDV;
603 				i++;
604 			}
605 			if (i == 0)
606 				break;
607 			j = i * sizeof(union cx25840_ir_fifo_rec);
608 			k = kfifo_in_locked(&ir_state->rx_kfifo,
609 					    (unsigned char *) rx_data, j,
610 					    &ir_state->rx_kfifo_lock);
611 			if (k != j)
612 				kror++; /* rx_kfifo over run */
613 		}
614 		*handled = true;
615 	}
616 
617 	events = 0;
618 	v = 0;
619 	if (kror) {
620 		events |= V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN;
621 		v4l2_err(sd, "IR receiver software FIFO overrun\n");
622 	}
623 	if (roe && ror) {
624 		/*
625 		 * The RX FIFO Enable (CNTRL_RFE) must be toggled to clear
626 		 * the Rx FIFO Over Run status (STATS_ROR)
627 		 */
628 		v |= CNTRL_RFE;
629 		events |= V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN;
630 		v4l2_err(sd, "IR receiver hardware FIFO overrun\n");
631 	}
632 	if (rte && rto) {
633 		/*
634 		 * The IR Receiver Enable (CNTRL_RXE) must be toggled to clear
635 		 * the Rx Pulse Width Timer Time Out (STATS_RTO)
636 		 */
637 		v |= CNTRL_RXE;
638 		events |= V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED;
639 	}
640 	if (v) {
641 		/* Clear STATS_ROR & STATS_RTO as needed by reseting hardware */
642 		cx25840_write4(c, CX25840_IR_CNTRL_REG, cntrl & ~v);
643 		cx25840_write4(c, CX25840_IR_CNTRL_REG, cntrl);
644 		*handled = true;
645 	}
646 	spin_lock_irqsave(&ir_state->rx_kfifo_lock, flags);
647 	if (kfifo_len(&ir_state->rx_kfifo) >= CX25840_IR_RX_KFIFO_SIZE / 2)
648 		events |= V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ;
649 	spin_unlock_irqrestore(&ir_state->rx_kfifo_lock, flags);
650 
651 	if (events)
652 		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_RX_NOTIFY, &events);
653 	return 0;
654 }
655 
656 /* Receiver */
657 static int cx25840_ir_rx_read(struct v4l2_subdev *sd, u8 *buf, size_t count,
658 			      ssize_t *num)
659 {
660 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
661 	bool invert;
662 	u16 divider;
663 	unsigned int i, n;
664 	union cx25840_ir_fifo_rec *p;
665 	unsigned u, v, w;
666 
667 	if (ir_state == NULL)
668 		return -ENODEV;
669 
670 	invert = (bool) atomic_read(&ir_state->rx_invert);
671 	divider = (u16) atomic_read(&ir_state->rxclk_divider);
672 
673 	n = count / sizeof(union cx25840_ir_fifo_rec)
674 		* sizeof(union cx25840_ir_fifo_rec);
675 	if (n == 0) {
676 		*num = 0;
677 		return 0;
678 	}
679 
680 	n = kfifo_out_locked(&ir_state->rx_kfifo, buf, n,
681 			     &ir_state->rx_kfifo_lock);
682 
683 	n /= sizeof(union cx25840_ir_fifo_rec);
684 	*num = n * sizeof(union cx25840_ir_fifo_rec);
685 
686 	for (p = (union cx25840_ir_fifo_rec *) buf, i = 0; i < n; p++, i++) {
687 
688 		if ((p->hw_fifo_data & FIFO_RXTX_RTO) == FIFO_RXTX_RTO) {
689 			/* Assume RTO was because of no IR light input */
690 			u = 0;
691 			w = 1;
692 		} else {
693 			u = (p->hw_fifo_data & FIFO_RXTX_LVL) ? 1 : 0;
694 			if (invert)
695 				u = u ? 0 : 1;
696 			w = 0;
697 		}
698 
699 		v = (unsigned) pulse_width_count_to_ns(
700 				  (u16) (p->hw_fifo_data & FIFO_RXTX), divider);
701 		if (v > IR_MAX_DURATION)
702 			v = IR_MAX_DURATION;
703 
704 		init_ir_raw_event(&p->ir_core_data);
705 		p->ir_core_data.pulse = u;
706 		p->ir_core_data.duration = v;
707 		p->ir_core_data.timeout = w;
708 
709 		v4l2_dbg(2, ir_debug, sd, "rx read: %10u ns  %s  %s\n",
710 			 v, u ? "mark" : "space", w ? "(timed out)" : "");
711 		if (w)
712 			v4l2_dbg(2, ir_debug, sd, "rx read: end of rx\n");
713 	}
714 	return 0;
715 }
716 
717 static int cx25840_ir_rx_g_parameters(struct v4l2_subdev *sd,
718 				      struct v4l2_subdev_ir_parameters *p)
719 {
720 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
721 
722 	if (ir_state == NULL)
723 		return -ENODEV;
724 
725 	mutex_lock(&ir_state->rx_params_lock);
726 	memcpy(p, &ir_state->rx_params,
727 				      sizeof(struct v4l2_subdev_ir_parameters));
728 	mutex_unlock(&ir_state->rx_params_lock);
729 	return 0;
730 }
731 
732 static int cx25840_ir_rx_shutdown(struct v4l2_subdev *sd)
733 {
734 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
735 	struct i2c_client *c;
736 
737 	if (ir_state == NULL)
738 		return -ENODEV;
739 
740 	c = ir_state->c;
741 	mutex_lock(&ir_state->rx_params_lock);
742 
743 	/* Disable or slow down all IR Rx circuits and counters */
744 	irqenable_rx(sd, 0);
745 	control_rx_enable(c, false);
746 	control_rx_demodulation_enable(c, false);
747 	control_rx_s_edge_detection(c, CNTRL_EDG_NONE);
748 	filter_rx_s_min_width(c, 0);
749 	cx25840_write4(c, CX25840_IR_RXCLK_REG, RXCLK_RCD);
750 
751 	ir_state->rx_params.shutdown = true;
752 
753 	mutex_unlock(&ir_state->rx_params_lock);
754 	return 0;
755 }
756 
757 static int cx25840_ir_rx_s_parameters(struct v4l2_subdev *sd,
758 				      struct v4l2_subdev_ir_parameters *p)
759 {
760 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
761 	struct i2c_client *c;
762 	struct v4l2_subdev_ir_parameters *o;
763 	u16 rxclk_divider;
764 
765 	if (ir_state == NULL)
766 		return -ENODEV;
767 
768 	if (p->shutdown)
769 		return cx25840_ir_rx_shutdown(sd);
770 
771 	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
772 		return -ENOSYS;
773 
774 	c = ir_state->c;
775 	o = &ir_state->rx_params;
776 
777 	mutex_lock(&ir_state->rx_params_lock);
778 
779 	o->shutdown = p->shutdown;
780 
781 	p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
782 	o->mode = p->mode;
783 
784 	p->bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec);
785 	o->bytes_per_data_element = p->bytes_per_data_element;
786 
787 	/* Before we tweak the hardware, we have to disable the receiver */
788 	irqenable_rx(sd, 0);
789 	control_rx_enable(c, false);
790 
791 	control_rx_demodulation_enable(c, p->modulation);
792 	o->modulation = p->modulation;
793 
794 	if (p->modulation) {
795 		p->carrier_freq = rxclk_rx_s_carrier(c, p->carrier_freq,
796 						     &rxclk_divider);
797 
798 		o->carrier_freq = p->carrier_freq;
799 
800 		p->duty_cycle = 50;
801 		o->duty_cycle = p->duty_cycle;
802 
803 		control_rx_s_carrier_window(c, p->carrier_freq,
804 					    &p->carrier_range_lower,
805 					    &p->carrier_range_upper);
806 		o->carrier_range_lower = p->carrier_range_lower;
807 		o->carrier_range_upper = p->carrier_range_upper;
808 
809 		p->max_pulse_width =
810 			(u32) pulse_width_count_to_ns(FIFO_RXTX, rxclk_divider);
811 	} else {
812 		p->max_pulse_width =
813 			    rxclk_rx_s_max_pulse_width(c, p->max_pulse_width,
814 						       &rxclk_divider);
815 	}
816 	o->max_pulse_width = p->max_pulse_width;
817 	atomic_set(&ir_state->rxclk_divider, rxclk_divider);
818 
819 	p->noise_filter_min_width =
820 			    filter_rx_s_min_width(c, p->noise_filter_min_width);
821 	o->noise_filter_min_width = p->noise_filter_min_width;
822 
823 	p->resolution = clock_divider_to_resolution(rxclk_divider);
824 	o->resolution = p->resolution;
825 
826 	/* FIXME - make this dependent on resolution for better performance */
827 	control_rx_irq_watermark(c, RX_FIFO_HALF_FULL);
828 
829 	control_rx_s_edge_detection(c, CNTRL_EDG_BOTH);
830 
831 	o->invert_level = p->invert_level;
832 	atomic_set(&ir_state->rx_invert, p->invert_level);
833 
834 	o->interrupt_enable = p->interrupt_enable;
835 	o->enable = p->enable;
836 	if (p->enable) {
837 		unsigned long flags;
838 
839 		spin_lock_irqsave(&ir_state->rx_kfifo_lock, flags);
840 		kfifo_reset(&ir_state->rx_kfifo);
841 		spin_unlock_irqrestore(&ir_state->rx_kfifo_lock, flags);
842 		if (p->interrupt_enable)
843 			irqenable_rx(sd, IRQEN_RSE | IRQEN_RTE | IRQEN_ROE);
844 		control_rx_enable(c, p->enable);
845 	}
846 
847 	mutex_unlock(&ir_state->rx_params_lock);
848 	return 0;
849 }
850 
851 /* Transmitter */
852 static int cx25840_ir_tx_write(struct v4l2_subdev *sd, u8 *buf, size_t count,
853 			       ssize_t *num)
854 {
855 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
856 
857 	if (ir_state == NULL)
858 		return -ENODEV;
859 
860 #if 0
861 	/*
862 	 * FIXME - the code below is an incomplete and untested sketch of what
863 	 * may need to be done.  The critical part is to get 4 (or 8) pulses
864 	 * from the tx_kfifo, or converted from ns to the proper units from the
865 	 * input, and push them off to the hardware Tx FIFO right away, if the
866 	 * HW TX fifo needs service.  The rest can be pushed to the tx_kfifo in
867 	 * a less critical timeframe.  Also watch out for overruning the
868 	 * tx_kfifo - don't let it happen and let the caller know not all his
869 	 * pulses were written.
870 	 */
871 	u32 *ns_pulse = (u32 *) buf;
872 	unsigned int n;
873 	u32 fifo_pulse[FIFO_TX_DEPTH];
874 	u32 mark;
875 
876 	/* Compute how much we can fit in the tx kfifo */
877 	n = CX25840_IR_TX_KFIFO_SIZE - kfifo_len(ir_state->tx_kfifo);
878 	n = min(n, (unsigned int) count);
879 	n /= sizeof(u32);
880 
881 	/* FIXME - turn on Tx Fifo service interrupt
882 	 * check hardware fifo level, and other stuff
883 	 */
884 	for (i = 0; i < n; ) {
885 		for (j = 0; j < FIFO_TX_DEPTH / 2 && i < n; j++) {
886 			mark = ns_pulse[i] & LEVEL_MASK;
887 			fifo_pulse[j] = ns_to_pulse_width_count(
888 					 ns_pulse[i] &
889 					       ~LEVEL_MASK,
890 					 ir_state->txclk_divider);
891 			if (mark)
892 				fifo_pulse[j] &= FIFO_RXTX_LVL;
893 			i++;
894 		}
895 		kfifo_put(ir_state->tx_kfifo, (u8 *) fifo_pulse,
896 							       j * sizeof(u32));
897 	}
898 	*num = n * sizeof(u32);
899 #else
900 	/* For now enable the Tx FIFO Service interrupt & pretend we did work */
901 	irqenable_tx(sd, IRQEN_TSE);
902 	*num = count;
903 #endif
904 	return 0;
905 }
906 
907 static int cx25840_ir_tx_g_parameters(struct v4l2_subdev *sd,
908 				      struct v4l2_subdev_ir_parameters *p)
909 {
910 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
911 
912 	if (ir_state == NULL)
913 		return -ENODEV;
914 
915 	mutex_lock(&ir_state->tx_params_lock);
916 	memcpy(p, &ir_state->tx_params,
917 				      sizeof(struct v4l2_subdev_ir_parameters));
918 	mutex_unlock(&ir_state->tx_params_lock);
919 	return 0;
920 }
921 
922 static int cx25840_ir_tx_shutdown(struct v4l2_subdev *sd)
923 {
924 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
925 	struct i2c_client *c;
926 
927 	if (ir_state == NULL)
928 		return -ENODEV;
929 
930 	c = ir_state->c;
931 	mutex_lock(&ir_state->tx_params_lock);
932 
933 	/* Disable or slow down all IR Tx circuits and counters */
934 	irqenable_tx(sd, 0);
935 	control_tx_enable(c, false);
936 	control_tx_modulation_enable(c, false);
937 	cx25840_write4(c, CX25840_IR_TXCLK_REG, TXCLK_TCD);
938 
939 	ir_state->tx_params.shutdown = true;
940 
941 	mutex_unlock(&ir_state->tx_params_lock);
942 	return 0;
943 }
944 
945 static int cx25840_ir_tx_s_parameters(struct v4l2_subdev *sd,
946 				      struct v4l2_subdev_ir_parameters *p)
947 {
948 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
949 	struct i2c_client *c;
950 	struct v4l2_subdev_ir_parameters *o;
951 	u16 txclk_divider;
952 
953 	if (ir_state == NULL)
954 		return -ENODEV;
955 
956 	if (p->shutdown)
957 		return cx25840_ir_tx_shutdown(sd);
958 
959 	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
960 		return -ENOSYS;
961 
962 	c = ir_state->c;
963 	o = &ir_state->tx_params;
964 	mutex_lock(&ir_state->tx_params_lock);
965 
966 	o->shutdown = p->shutdown;
967 
968 	p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
969 	o->mode = p->mode;
970 
971 	p->bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec);
972 	o->bytes_per_data_element = p->bytes_per_data_element;
973 
974 	/* Before we tweak the hardware, we have to disable the transmitter */
975 	irqenable_tx(sd, 0);
976 	control_tx_enable(c, false);
977 
978 	control_tx_modulation_enable(c, p->modulation);
979 	o->modulation = p->modulation;
980 
981 	if (p->modulation) {
982 		p->carrier_freq = txclk_tx_s_carrier(c, p->carrier_freq,
983 						     &txclk_divider);
984 		o->carrier_freq = p->carrier_freq;
985 
986 		p->duty_cycle = cduty_tx_s_duty_cycle(c, p->duty_cycle);
987 		o->duty_cycle = p->duty_cycle;
988 
989 		p->max_pulse_width =
990 			(u32) pulse_width_count_to_ns(FIFO_RXTX, txclk_divider);
991 	} else {
992 		p->max_pulse_width =
993 			    txclk_tx_s_max_pulse_width(c, p->max_pulse_width,
994 						       &txclk_divider);
995 	}
996 	o->max_pulse_width = p->max_pulse_width;
997 	atomic_set(&ir_state->txclk_divider, txclk_divider);
998 
999 	p->resolution = clock_divider_to_resolution(txclk_divider);
1000 	o->resolution = p->resolution;
1001 
1002 	/* FIXME - make this dependent on resolution for better performance */
1003 	control_tx_irq_watermark(c, TX_FIFO_HALF_EMPTY);
1004 
1005 	control_tx_polarity_invert(c, p->invert_carrier_sense);
1006 	o->invert_carrier_sense = p->invert_carrier_sense;
1007 
1008 	/*
1009 	 * FIXME: we don't have hardware help for IO pin level inversion
1010 	 * here like we have on the CX23888.
1011 	 * Act on this with some mix of logical inversion of data levels,
1012 	 * carrier polarity, and carrier duty cycle.
1013 	 */
1014 	o->invert_level = p->invert_level;
1015 
1016 	o->interrupt_enable = p->interrupt_enable;
1017 	o->enable = p->enable;
1018 	if (p->enable) {
1019 		/* reset tx_fifo here */
1020 		if (p->interrupt_enable)
1021 			irqenable_tx(sd, IRQEN_TSE);
1022 		control_tx_enable(c, p->enable);
1023 	}
1024 
1025 	mutex_unlock(&ir_state->tx_params_lock);
1026 	return 0;
1027 }
1028 
1029 
1030 /*
1031  * V4L2 Subdevice Core Ops support
1032  */
1033 int cx25840_ir_log_status(struct v4l2_subdev *sd)
1034 {
1035 	struct cx25840_state *state = to_state(sd);
1036 	struct i2c_client *c = state->c;
1037 	char *s;
1038 	int i, j;
1039 	u32 cntrl, txclk, rxclk, cduty, stats, irqen, filtr;
1040 
1041 	/* The CX23888 chip doesn't have an IR controller on the A/V core */
1042 	if (is_cx23888(state))
1043 		return 0;
1044 
1045 	cntrl = cx25840_read4(c, CX25840_IR_CNTRL_REG);
1046 	txclk = cx25840_read4(c, CX25840_IR_TXCLK_REG) & TXCLK_TCD;
1047 	rxclk = cx25840_read4(c, CX25840_IR_RXCLK_REG) & RXCLK_RCD;
1048 	cduty = cx25840_read4(c, CX25840_IR_CDUTY_REG) & CDUTY_CDC;
1049 	stats = cx25840_read4(c, CX25840_IR_STATS_REG);
1050 	irqen = cx25840_read4(c, CX25840_IR_IRQEN_REG);
1051 	if (is_cx23885(state) || is_cx23887(state))
1052 		irqen ^= IRQEN_MSK;
1053 	filtr = cx25840_read4(c, CX25840_IR_FILTR_REG) & FILTR_LPF;
1054 
1055 	v4l2_info(sd, "IR Receiver:\n");
1056 	v4l2_info(sd, "\tEnabled:                           %s\n",
1057 		  cntrl & CNTRL_RXE ? "yes" : "no");
1058 	v4l2_info(sd, "\tDemodulation from a carrier:       %s\n",
1059 		  cntrl & CNTRL_DMD ? "enabled" : "disabled");
1060 	v4l2_info(sd, "\tFIFO:                              %s\n",
1061 		  cntrl & CNTRL_RFE ? "enabled" : "disabled");
1062 	switch (cntrl & CNTRL_EDG) {
1063 	case CNTRL_EDG_NONE:
1064 		s = "disabled";
1065 		break;
1066 	case CNTRL_EDG_FALL:
1067 		s = "falling edge";
1068 		break;
1069 	case CNTRL_EDG_RISE:
1070 		s = "rising edge";
1071 		break;
1072 	case CNTRL_EDG_BOTH:
1073 		s = "rising & falling edges";
1074 		break;
1075 	default:
1076 		s = "??? edge";
1077 		break;
1078 	}
1079 	v4l2_info(sd, "\tPulse timers' start/stop trigger:  %s\n", s);
1080 	v4l2_info(sd, "\tFIFO data on pulse timer overflow: %s\n",
1081 		  cntrl & CNTRL_R ? "not loaded" : "overflow marker");
1082 	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1083 		  cntrl & CNTRL_RIC ? "not empty" : "half full or greater");
1084 	v4l2_info(sd, "\tLoopback mode:                     %s\n",
1085 		  cntrl & CNTRL_LBM ? "loopback active" : "normal receive");
1086 	if (cntrl & CNTRL_DMD) {
1087 		v4l2_info(sd, "\tExpected carrier (16 clocks):      %u Hz\n",
1088 			  clock_divider_to_carrier_freq(rxclk));
1089 		switch (cntrl & CNTRL_WIN) {
1090 		case CNTRL_WIN_3_3:
1091 			i = 3;
1092 			j = 3;
1093 			break;
1094 		case CNTRL_WIN_4_3:
1095 			i = 4;
1096 			j = 3;
1097 			break;
1098 		case CNTRL_WIN_3_4:
1099 			i = 3;
1100 			j = 4;
1101 			break;
1102 		case CNTRL_WIN_4_4:
1103 			i = 4;
1104 			j = 4;
1105 			break;
1106 		default:
1107 			i = 0;
1108 			j = 0;
1109 			break;
1110 		}
1111 		v4l2_info(sd, "\tNext carrier edge window:	    16 clocks -%1d/+%1d, %u to %u Hz\n",
1112 			  i, j,
1113 			  clock_divider_to_freq(rxclk, 16 + j),
1114 			  clock_divider_to_freq(rxclk, 16 - i));
1115 	}
1116 	v4l2_info(sd, "\tMax measurable pulse width:        %u us, %llu ns\n",
1117 		  pulse_width_count_to_us(FIFO_RXTX, rxclk),
1118 		  pulse_width_count_to_ns(FIFO_RXTX, rxclk));
1119 	v4l2_info(sd, "\tLow pass filter:                   %s\n",
1120 		  filtr ? "enabled" : "disabled");
1121 	if (filtr)
1122 		v4l2_info(sd, "\tMin acceptable pulse width (LPF):  %u us, %u ns\n",
1123 			  lpf_count_to_us(filtr),
1124 			  lpf_count_to_ns(filtr));
1125 	v4l2_info(sd, "\tPulse width timer timed-out:       %s\n",
1126 		  stats & STATS_RTO ? "yes" : "no");
1127 	v4l2_info(sd, "\tPulse width timer time-out intr:   %s\n",
1128 		  irqen & IRQEN_RTE ? "enabled" : "disabled");
1129 	v4l2_info(sd, "\tFIFO overrun:                      %s\n",
1130 		  stats & STATS_ROR ? "yes" : "no");
1131 	v4l2_info(sd, "\tFIFO overrun interrupt:            %s\n",
1132 		  irqen & IRQEN_ROE ? "enabled" : "disabled");
1133 	v4l2_info(sd, "\tBusy:                              %s\n",
1134 		  stats & STATS_RBY ? "yes" : "no");
1135 	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1136 		  stats & STATS_RSR ? "yes" : "no");
1137 	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1138 		  irqen & IRQEN_RSE ? "enabled" : "disabled");
1139 
1140 	v4l2_info(sd, "IR Transmitter:\n");
1141 	v4l2_info(sd, "\tEnabled:                           %s\n",
1142 		  cntrl & CNTRL_TXE ? "yes" : "no");
1143 	v4l2_info(sd, "\tModulation onto a carrier:         %s\n",
1144 		  cntrl & CNTRL_MOD ? "enabled" : "disabled");
1145 	v4l2_info(sd, "\tFIFO:                              %s\n",
1146 		  cntrl & CNTRL_TFE ? "enabled" : "disabled");
1147 	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1148 		  cntrl & CNTRL_TIC ? "not empty" : "half full or less");
1149 	v4l2_info(sd, "\tCarrier polarity:                  %s\n",
1150 		  cntrl & CNTRL_CPL ? "space:burst mark:noburst"
1151 				    : "space:noburst mark:burst");
1152 	if (cntrl & CNTRL_MOD) {
1153 		v4l2_info(sd, "\tCarrier (16 clocks):               %u Hz\n",
1154 			  clock_divider_to_carrier_freq(txclk));
1155 		v4l2_info(sd, "\tCarrier duty cycle:                %2u/16\n",
1156 			  cduty + 1);
1157 	}
1158 	v4l2_info(sd, "\tMax pulse width:                   %u us, %llu ns\n",
1159 		  pulse_width_count_to_us(FIFO_RXTX, txclk),
1160 		  pulse_width_count_to_ns(FIFO_RXTX, txclk));
1161 	v4l2_info(sd, "\tBusy:                              %s\n",
1162 		  stats & STATS_TBY ? "yes" : "no");
1163 	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1164 		  stats & STATS_TSR ? "yes" : "no");
1165 	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1166 		  irqen & IRQEN_TSE ? "enabled" : "disabled");
1167 
1168 	return 0;
1169 }
1170 
1171 
1172 const struct v4l2_subdev_ir_ops cx25840_ir_ops = {
1173 	.rx_read = cx25840_ir_rx_read,
1174 	.rx_g_parameters = cx25840_ir_rx_g_parameters,
1175 	.rx_s_parameters = cx25840_ir_rx_s_parameters,
1176 
1177 	.tx_write = cx25840_ir_tx_write,
1178 	.tx_g_parameters = cx25840_ir_tx_g_parameters,
1179 	.tx_s_parameters = cx25840_ir_tx_s_parameters,
1180 };
1181 
1182 
1183 static const struct v4l2_subdev_ir_parameters default_rx_params = {
1184 	.bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec),
1185 	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1186 
1187 	.enable = false,
1188 	.interrupt_enable = false,
1189 	.shutdown = true,
1190 
1191 	.modulation = true,
1192 	.carrier_freq = 36000, /* 36 kHz - RC-5, and RC-6 carrier */
1193 
1194 	/* RC-5: 666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
1195 	/* RC-6: 333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
1196 	.noise_filter_min_width = 333333, /* ns */
1197 	.carrier_range_lower = 35000,
1198 	.carrier_range_upper = 37000,
1199 	.invert_level = false,
1200 };
1201 
1202 static const struct v4l2_subdev_ir_parameters default_tx_params = {
1203 	.bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec),
1204 	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1205 
1206 	.enable = false,
1207 	.interrupt_enable = false,
1208 	.shutdown = true,
1209 
1210 	.modulation = true,
1211 	.carrier_freq = 36000, /* 36 kHz - RC-5 carrier */
1212 	.duty_cycle = 25,      /* 25 %   - RC-5 carrier */
1213 	.invert_level = false,
1214 	.invert_carrier_sense = false,
1215 };
1216 
1217 int cx25840_ir_probe(struct v4l2_subdev *sd)
1218 {
1219 	struct cx25840_state *state = to_state(sd);
1220 	struct cx25840_ir_state *ir_state;
1221 	struct v4l2_subdev_ir_parameters default_params;
1222 
1223 	/* Only init the IR controller for the CX2388[57] AV Core for now */
1224 	if (!(is_cx23885(state) || is_cx23887(state)))
1225 		return 0;
1226 
1227 	ir_state = devm_kzalloc(&state->c->dev, sizeof(*ir_state), GFP_KERNEL);
1228 	if (ir_state == NULL)
1229 		return -ENOMEM;
1230 
1231 	spin_lock_init(&ir_state->rx_kfifo_lock);
1232 	if (kfifo_alloc(&ir_state->rx_kfifo,
1233 			CX25840_IR_RX_KFIFO_SIZE, GFP_KERNEL))
1234 		return -ENOMEM;
1235 
1236 	ir_state->c = state->c;
1237 	state->ir_state = ir_state;
1238 
1239 	/* Ensure no interrupts arrive yet */
1240 	if (is_cx23885(state) || is_cx23887(state))
1241 		cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, IRQEN_MSK);
1242 	else
1243 		cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, 0);
1244 
1245 	mutex_init(&ir_state->rx_params_lock);
1246 	default_params = default_rx_params;
1247 	v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);
1248 
1249 	mutex_init(&ir_state->tx_params_lock);
1250 	default_params = default_tx_params;
1251 	v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
1252 
1253 	return 0;
1254 }
1255 
1256 int cx25840_ir_remove(struct v4l2_subdev *sd)
1257 {
1258 	struct cx25840_state *state = to_state(sd);
1259 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
1260 
1261 	if (ir_state == NULL)
1262 		return -ENODEV;
1263 
1264 	cx25840_ir_rx_shutdown(sd);
1265 	cx25840_ir_tx_shutdown(sd);
1266 
1267 	kfifo_free(&ir_state->rx_kfifo);
1268 	state->ir_state = NULL;
1269 	return 0;
1270 }
1271