1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Driver for the Conexant CX2584x Audio/Video decoder chip and related cores
4  *
5  *  Integrated Consumer Infrared Controller
6  *
7  *  Copyright (C) 2010  Andy Walls <awalls@md.metrocast.net>
8  */
9 
10 #include <linux/slab.h>
11 #include <linux/kfifo.h>
12 #include <linux/module.h>
13 #include <media/drv-intf/cx25840.h>
14 #include <media/rc-core.h>
15 
16 #include "cx25840-core.h"
17 
18 static unsigned int ir_debug;
19 module_param(ir_debug, int, 0644);
20 MODULE_PARM_DESC(ir_debug, "enable integrated IR debug messages");
21 
22 #define CX25840_IR_REG_BASE	0x200
23 
24 #define CX25840_IR_CNTRL_REG	0x200
25 #define CNTRL_WIN_3_3	0x00000000
26 #define CNTRL_WIN_4_3	0x00000001
27 #define CNTRL_WIN_3_4	0x00000002
28 #define CNTRL_WIN_4_4	0x00000003
29 #define CNTRL_WIN	0x00000003
30 #define CNTRL_EDG_NONE	0x00000000
31 #define CNTRL_EDG_FALL	0x00000004
32 #define CNTRL_EDG_RISE	0x00000008
33 #define CNTRL_EDG_BOTH	0x0000000C
34 #define CNTRL_EDG	0x0000000C
35 #define CNTRL_DMD	0x00000010
36 #define CNTRL_MOD	0x00000020
37 #define CNTRL_RFE	0x00000040
38 #define CNTRL_TFE	0x00000080
39 #define CNTRL_RXE	0x00000100
40 #define CNTRL_TXE	0x00000200
41 #define CNTRL_RIC	0x00000400
42 #define CNTRL_TIC	0x00000800
43 #define CNTRL_CPL	0x00001000
44 #define CNTRL_LBM	0x00002000
45 #define CNTRL_R		0x00004000
46 
47 #define CX25840_IR_TXCLK_REG	0x204
48 #define TXCLK_TCD	0x0000FFFF
49 
50 #define CX25840_IR_RXCLK_REG	0x208
51 #define RXCLK_RCD	0x0000FFFF
52 
53 #define CX25840_IR_CDUTY_REG	0x20C
54 #define CDUTY_CDC	0x0000000F
55 
56 #define CX25840_IR_STATS_REG	0x210
57 #define STATS_RTO	0x00000001
58 #define STATS_ROR	0x00000002
59 #define STATS_RBY	0x00000004
60 #define STATS_TBY	0x00000008
61 #define STATS_RSR	0x00000010
62 #define STATS_TSR	0x00000020
63 
64 #define CX25840_IR_IRQEN_REG	0x214
65 #define IRQEN_RTE	0x00000001
66 #define IRQEN_ROE	0x00000002
67 #define IRQEN_RSE	0x00000010
68 #define IRQEN_TSE	0x00000020
69 #define IRQEN_MSK	0x00000033
70 
71 #define CX25840_IR_FILTR_REG	0x218
72 #define FILTR_LPF	0x0000FFFF
73 
74 #define CX25840_IR_FIFO_REG	0x23C
75 #define FIFO_RXTX	0x0000FFFF
76 #define FIFO_RXTX_LVL	0x00010000
77 #define FIFO_RXTX_RTO	0x0001FFFF
78 #define FIFO_RX_NDV	0x00020000
79 #define FIFO_RX_DEPTH	8
80 #define FIFO_TX_DEPTH	8
81 
82 #define CX25840_VIDCLK_FREQ	108000000 /* 108 MHz, BT.656 */
83 #define CX25840_IR_REFCLK_FREQ	(CX25840_VIDCLK_FREQ / 2)
84 
85 /*
86  * We use this union internally for convenience, but callers to tx_write
87  * and rx_read will be expecting records of type struct ir_raw_event.
88  * Always ensure the size of this union is dictated by struct ir_raw_event.
89  */
90 union cx25840_ir_fifo_rec {
91 	u32 hw_fifo_data;
92 	struct ir_raw_event ir_core_data;
93 };
94 
95 #define CX25840_IR_RX_KFIFO_SIZE    (256 * sizeof(union cx25840_ir_fifo_rec))
96 #define CX25840_IR_TX_KFIFO_SIZE    (256 * sizeof(union cx25840_ir_fifo_rec))
97 
98 struct cx25840_ir_state {
99 	struct i2c_client *c;
100 
101 	struct v4l2_subdev_ir_parameters rx_params;
102 	struct mutex rx_params_lock; /* protects Rx parameter settings cache */
103 	atomic_t rxclk_divider;
104 	atomic_t rx_invert;
105 
106 	struct kfifo rx_kfifo;
107 	spinlock_t rx_kfifo_lock; /* protect Rx data kfifo */
108 
109 	struct v4l2_subdev_ir_parameters tx_params;
110 	struct mutex tx_params_lock; /* protects Tx parameter settings cache */
111 	atomic_t txclk_divider;
112 };
113 
114 static inline struct cx25840_ir_state *to_ir_state(struct v4l2_subdev *sd)
115 {
116 	struct cx25840_state *state = to_state(sd);
117 	return state ? state->ir_state : NULL;
118 }
119 
120 
121 /*
122  * Rx and Tx Clock Divider register computations
123  *
124  * Note the largest clock divider value of 0xffff corresponds to:
125  *	(0xffff + 1) * 1000 / 108/2 MHz = 1,213,629.629... ns
126  * which fits in 21 bits, so we'll use unsigned int for time arguments.
127  */
128 static inline u16 count_to_clock_divider(unsigned int d)
129 {
130 	if (d > RXCLK_RCD + 1)
131 		d = RXCLK_RCD;
132 	else if (d < 2)
133 		d = 1;
134 	else
135 		d--;
136 	return (u16) d;
137 }
138 
139 static inline u16 ns_to_clock_divider(unsigned int ns)
140 {
141 	return count_to_clock_divider(
142 		DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ / 1000000 * ns, 1000));
143 }
144 
145 static inline unsigned int clock_divider_to_ns(unsigned int divider)
146 {
147 	/* Period of the Rx or Tx clock in ns */
148 	return DIV_ROUND_CLOSEST((divider + 1) * 1000,
149 				 CX25840_IR_REFCLK_FREQ / 1000000);
150 }
151 
152 static inline u16 carrier_freq_to_clock_divider(unsigned int freq)
153 {
154 	return count_to_clock_divider(
155 			  DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, freq * 16));
156 }
157 
158 static inline unsigned int clock_divider_to_carrier_freq(unsigned int divider)
159 {
160 	return DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, (divider + 1) * 16);
161 }
162 
163 static inline u16 freq_to_clock_divider(unsigned int freq,
164 					unsigned int rollovers)
165 {
166 	return count_to_clock_divider(
167 		   DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ, freq * rollovers));
168 }
169 
170 static inline unsigned int clock_divider_to_freq(unsigned int divider,
171 						 unsigned int rollovers)
172 {
173 	return DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ,
174 				 (divider + 1) * rollovers);
175 }
176 
177 /*
178  * Low Pass Filter register calculations
179  *
180  * Note the largest count value of 0xffff corresponds to:
181  *	0xffff * 1000 / 108/2 MHz = 1,213,611.11... ns
182  * which fits in 21 bits, so we'll use unsigned int for time arguments.
183  */
184 static inline u16 count_to_lpf_count(unsigned int d)
185 {
186 	if (d > FILTR_LPF)
187 		d = FILTR_LPF;
188 	else if (d < 4)
189 		d = 0;
190 	return (u16) d;
191 }
192 
193 static inline u16 ns_to_lpf_count(unsigned int ns)
194 {
195 	return count_to_lpf_count(
196 		DIV_ROUND_CLOSEST(CX25840_IR_REFCLK_FREQ / 1000000 * ns, 1000));
197 }
198 
199 static inline unsigned int lpf_count_to_ns(unsigned int count)
200 {
201 	/* Duration of the Low Pass Filter rejection window in ns */
202 	return DIV_ROUND_CLOSEST(count * 1000,
203 				 CX25840_IR_REFCLK_FREQ / 1000000);
204 }
205 
206 static inline unsigned int lpf_count_to_us(unsigned int count)
207 {
208 	/* Duration of the Low Pass Filter rejection window in us */
209 	return DIV_ROUND_CLOSEST(count, CX25840_IR_REFCLK_FREQ / 1000000);
210 }
211 
212 /*
213  * FIFO register pulse width count computations
214  */
215 static u32 clock_divider_to_resolution(u16 divider)
216 {
217 	/*
218 	 * Resolution is the duration of 1 tick of the readable portion of
219 	 * of the pulse width counter as read from the FIFO.  The two lsb's are
220 	 * not readable, hence the << 2.  This function returns ns.
221 	 */
222 	return DIV_ROUND_CLOSEST((1 << 2)  * ((u32) divider + 1) * 1000,
223 				 CX25840_IR_REFCLK_FREQ / 1000000);
224 }
225 
226 static u64 pulse_width_count_to_ns(u16 count, u16 divider)
227 {
228 	u64 n;
229 	u32 rem;
230 
231 	/*
232 	 * The 2 lsb's of the pulse width timer count are not readable, hence
233 	 * the (count << 2) | 0x3
234 	 */
235 	n = (((u64) count << 2) | 0x3) * (divider + 1) * 1000; /* millicycles */
236 	rem = do_div(n, CX25840_IR_REFCLK_FREQ / 1000000);     /* / MHz => ns */
237 	if (rem >= CX25840_IR_REFCLK_FREQ / 1000000 / 2)
238 		n++;
239 	return n;
240 }
241 
242 #if 0
243 /* Keep as we will need this for Transmit functionality */
244 static u16 ns_to_pulse_width_count(u32 ns, u16 divider)
245 {
246 	u64 n;
247 	u32 d;
248 	u32 rem;
249 
250 	/*
251 	 * The 2 lsb's of the pulse width timer count are not accessible, hence
252 	 * the (1 << 2)
253 	 */
254 	n = ((u64) ns) * CX25840_IR_REFCLK_FREQ / 1000000; /* millicycles */
255 	d = (1 << 2) * ((u32) divider + 1) * 1000; /* millicycles/count */
256 	rem = do_div(n, d);
257 	if (rem >= d / 2)
258 		n++;
259 
260 	if (n > FIFO_RXTX)
261 		n = FIFO_RXTX;
262 	else if (n == 0)
263 		n = 1;
264 	return (u16) n;
265 }
266 
267 #endif
268 static unsigned int pulse_width_count_to_us(u16 count, u16 divider)
269 {
270 	u64 n;
271 	u32 rem;
272 
273 	/*
274 	 * The 2 lsb's of the pulse width timer count are not readable, hence
275 	 * the (count << 2) | 0x3
276 	 */
277 	n = (((u64) count << 2) | 0x3) * (divider + 1);    /* cycles      */
278 	rem = do_div(n, CX25840_IR_REFCLK_FREQ / 1000000); /* / MHz => us */
279 	if (rem >= CX25840_IR_REFCLK_FREQ / 1000000 / 2)
280 		n++;
281 	return (unsigned int) n;
282 }
283 
284 /*
285  * Pulse Clocks computations: Combined Pulse Width Count & Rx Clock Counts
286  *
287  * The total pulse clock count is an 18 bit pulse width timer count as the most
288  * significant part and (up to) 16 bit clock divider count as a modulus.
289  * When the Rx clock divider ticks down to 0, it increments the 18 bit pulse
290  * width timer count's least significant bit.
291  */
292 static u64 ns_to_pulse_clocks(u32 ns)
293 {
294 	u64 clocks;
295 	u32 rem;
296 	clocks = CX25840_IR_REFCLK_FREQ / 1000000 * (u64) ns; /* millicycles  */
297 	rem = do_div(clocks, 1000);                         /* /1000 = cycles */
298 	if (rem >= 1000 / 2)
299 		clocks++;
300 	return clocks;
301 }
302 
303 static u16 pulse_clocks_to_clock_divider(u64 count)
304 {
305 	do_div(count, (FIFO_RXTX << 2) | 0x3);
306 
307 	/* net result needs to be rounded down and decremented by 1 */
308 	if (count > RXCLK_RCD + 1)
309 		count = RXCLK_RCD;
310 	else if (count < 2)
311 		count = 1;
312 	else
313 		count--;
314 	return (u16) count;
315 }
316 
317 /*
318  * IR Control Register helpers
319  */
320 enum tx_fifo_watermark {
321 	TX_FIFO_HALF_EMPTY = 0,
322 	TX_FIFO_EMPTY      = CNTRL_TIC,
323 };
324 
325 enum rx_fifo_watermark {
326 	RX_FIFO_HALF_FULL = 0,
327 	RX_FIFO_NOT_EMPTY = CNTRL_RIC,
328 };
329 
330 static inline void control_tx_irq_watermark(struct i2c_client *c,
331 					    enum tx_fifo_watermark level)
332 {
333 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_TIC, level);
334 }
335 
336 static inline void control_rx_irq_watermark(struct i2c_client *c,
337 					    enum rx_fifo_watermark level)
338 {
339 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_RIC, level);
340 }
341 
342 static inline void control_tx_enable(struct i2c_client *c, bool enable)
343 {
344 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~(CNTRL_TXE | CNTRL_TFE),
345 			enable ? (CNTRL_TXE | CNTRL_TFE) : 0);
346 }
347 
348 static inline void control_rx_enable(struct i2c_client *c, bool enable)
349 {
350 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~(CNTRL_RXE | CNTRL_RFE),
351 			enable ? (CNTRL_RXE | CNTRL_RFE) : 0);
352 }
353 
354 static inline void control_tx_modulation_enable(struct i2c_client *c,
355 						bool enable)
356 {
357 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_MOD,
358 			enable ? CNTRL_MOD : 0);
359 }
360 
361 static inline void control_rx_demodulation_enable(struct i2c_client *c,
362 						  bool enable)
363 {
364 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_DMD,
365 			enable ? CNTRL_DMD : 0);
366 }
367 
368 static inline void control_rx_s_edge_detection(struct i2c_client *c,
369 					       u32 edge_types)
370 {
371 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_EDG_BOTH,
372 			edge_types & CNTRL_EDG_BOTH);
373 }
374 
375 static void control_rx_s_carrier_window(struct i2c_client *c,
376 					unsigned int carrier,
377 					unsigned int *carrier_range_low,
378 					unsigned int *carrier_range_high)
379 {
380 	u32 v;
381 	unsigned int c16 = carrier * 16;
382 
383 	if (*carrier_range_low < DIV_ROUND_CLOSEST(c16, 16 + 3)) {
384 		v = CNTRL_WIN_3_4;
385 		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 4);
386 	} else {
387 		v = CNTRL_WIN_3_3;
388 		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 3);
389 	}
390 
391 	if (*carrier_range_high > DIV_ROUND_CLOSEST(c16, 16 - 3)) {
392 		v |= CNTRL_WIN_4_3;
393 		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 4);
394 	} else {
395 		v |= CNTRL_WIN_3_3;
396 		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 3);
397 	}
398 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_WIN, v);
399 }
400 
401 static inline void control_tx_polarity_invert(struct i2c_client *c,
402 					      bool invert)
403 {
404 	cx25840_and_or4(c, CX25840_IR_CNTRL_REG, ~CNTRL_CPL,
405 			invert ? CNTRL_CPL : 0);
406 }
407 
408 /*
409  * IR Rx & Tx Clock Register helpers
410  */
411 static unsigned int txclk_tx_s_carrier(struct i2c_client *c,
412 				       unsigned int freq,
413 				       u16 *divider)
414 {
415 	*divider = carrier_freq_to_clock_divider(freq);
416 	cx25840_write4(c, CX25840_IR_TXCLK_REG, *divider);
417 	return clock_divider_to_carrier_freq(*divider);
418 }
419 
420 static unsigned int rxclk_rx_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_RXCLK_REG, *divider);
426 	return clock_divider_to_carrier_freq(*divider);
427 }
428 
429 static u32 txclk_tx_s_max_pulse_width(struct i2c_client *c, u32 ns,
430 				      u16 *divider)
431 {
432 	u64 pulse_clocks;
433 
434 	if (ns > IR_MAX_DURATION)
435 		ns = IR_MAX_DURATION;
436 	pulse_clocks = ns_to_pulse_clocks(ns);
437 	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
438 	cx25840_write4(c, CX25840_IR_TXCLK_REG, *divider);
439 	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
440 }
441 
442 static u32 rxclk_rx_s_max_pulse_width(struct i2c_client *c, u32 ns,
443 				      u16 *divider)
444 {
445 	u64 pulse_clocks;
446 
447 	if (ns > IR_MAX_DURATION)
448 		ns = IR_MAX_DURATION;
449 	pulse_clocks = ns_to_pulse_clocks(ns);
450 	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
451 	cx25840_write4(c, CX25840_IR_RXCLK_REG, *divider);
452 	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
453 }
454 
455 /*
456  * IR Tx Carrier Duty Cycle register helpers
457  */
458 static unsigned int cduty_tx_s_duty_cycle(struct i2c_client *c,
459 					  unsigned int duty_cycle)
460 {
461 	u32 n;
462 	n = DIV_ROUND_CLOSEST(duty_cycle * 100, 625); /* 16ths of 100% */
463 	if (n != 0)
464 		n--;
465 	if (n > 15)
466 		n = 15;
467 	cx25840_write4(c, CX25840_IR_CDUTY_REG, n);
468 	return DIV_ROUND_CLOSEST((n + 1) * 100, 16);
469 }
470 
471 /*
472  * IR Filter Register helpers
473  */
474 static u32 filter_rx_s_min_width(struct i2c_client *c, u32 min_width_ns)
475 {
476 	u32 count = ns_to_lpf_count(min_width_ns);
477 	cx25840_write4(c, CX25840_IR_FILTR_REG, count);
478 	return lpf_count_to_ns(count);
479 }
480 
481 /*
482  * IR IRQ Enable Register helpers
483  */
484 static inline void irqenable_rx(struct v4l2_subdev *sd, u32 mask)
485 {
486 	struct cx25840_state *state = to_state(sd);
487 
488 	if (is_cx23885(state) || is_cx23887(state))
489 		mask ^= IRQEN_MSK;
490 	mask &= (IRQEN_RTE | IRQEN_ROE | IRQEN_RSE);
491 	cx25840_and_or4(state->c, CX25840_IR_IRQEN_REG,
492 			~(IRQEN_RTE | IRQEN_ROE | IRQEN_RSE), mask);
493 }
494 
495 static inline void irqenable_tx(struct v4l2_subdev *sd, u32 mask)
496 {
497 	struct cx25840_state *state = to_state(sd);
498 
499 	if (is_cx23885(state) || is_cx23887(state))
500 		mask ^= IRQEN_MSK;
501 	mask &= IRQEN_TSE;
502 	cx25840_and_or4(state->c, CX25840_IR_IRQEN_REG, ~IRQEN_TSE, mask);
503 }
504 
505 /*
506  * V4L2 Subdevice IR Ops
507  */
508 int cx25840_ir_irq_handler(struct v4l2_subdev *sd, u32 status, bool *handled)
509 {
510 	struct cx25840_state *state = to_state(sd);
511 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
512 	struct i2c_client *c = NULL;
513 	unsigned long flags;
514 
515 	union cx25840_ir_fifo_rec rx_data[FIFO_RX_DEPTH];
516 	unsigned int i, j, k;
517 	u32 events, v;
518 	int tsr, rsr, rto, ror, tse, rse, rte, roe, kror;
519 	u32 cntrl, irqen, stats;
520 
521 	*handled = false;
522 	if (ir_state == NULL)
523 		return -ENODEV;
524 
525 	c = ir_state->c;
526 
527 	/* Only support the IR controller for the CX2388[57] AV Core for now */
528 	if (!(is_cx23885(state) || is_cx23887(state)))
529 		return -ENODEV;
530 
531 	cntrl = cx25840_read4(c, CX25840_IR_CNTRL_REG);
532 	irqen = cx25840_read4(c, CX25840_IR_IRQEN_REG);
533 	if (is_cx23885(state) || is_cx23887(state))
534 		irqen ^= IRQEN_MSK;
535 	stats = cx25840_read4(c, CX25840_IR_STATS_REG);
536 
537 	tsr = stats & STATS_TSR; /* Tx FIFO Service Request */
538 	rsr = stats & STATS_RSR; /* Rx FIFO Service Request */
539 	rto = stats & STATS_RTO; /* Rx Pulse Width Timer Time Out */
540 	ror = stats & STATS_ROR; /* Rx FIFO Over Run */
541 
542 	tse = irqen & IRQEN_TSE; /* Tx FIFO Service Request IRQ Enable */
543 	rse = irqen & IRQEN_RSE; /* Rx FIFO Service Request IRQ Enable */
544 	rte = irqen & IRQEN_RTE; /* Rx Pulse Width Timer Time Out IRQ Enable */
545 	roe = irqen & IRQEN_ROE; /* Rx FIFO Over Run IRQ Enable */
546 
547 	v4l2_dbg(2, ir_debug, sd, "IR IRQ Status:  %s %s %s %s %s %s\n",
548 		 tsr ? "tsr" : "   ", rsr ? "rsr" : "   ",
549 		 rto ? "rto" : "   ", ror ? "ror" : "   ",
550 		 stats & STATS_TBY ? "tby" : "   ",
551 		 stats & STATS_RBY ? "rby" : "   ");
552 
553 	v4l2_dbg(2, ir_debug, sd, "IR IRQ Enables: %s %s %s %s\n",
554 		 tse ? "tse" : "   ", rse ? "rse" : "   ",
555 		 rte ? "rte" : "   ", roe ? "roe" : "   ");
556 
557 	/*
558 	 * Transmitter interrupt service
559 	 */
560 	if (tse && tsr) {
561 		/*
562 		 * TODO:
563 		 * Check the watermark threshold setting
564 		 * Pull FIFO_TX_DEPTH or FIFO_TX_DEPTH/2 entries from tx_kfifo
565 		 * Push the data to the hardware FIFO.
566 		 * If there was nothing more to send in the tx_kfifo, disable
567 		 *	the TSR IRQ and notify the v4l2_device.
568 		 * If there was something in the tx_kfifo, check the tx_kfifo
569 		 *      level and notify the v4l2_device, if it is low.
570 		 */
571 		/* For now, inhibit TSR interrupt until Tx is implemented */
572 		irqenable_tx(sd, 0);
573 		events = V4L2_SUBDEV_IR_TX_FIFO_SERVICE_REQ;
574 		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_TX_NOTIFY, &events);
575 		*handled = true;
576 	}
577 
578 	/*
579 	 * Receiver interrupt service
580 	 */
581 	kror = 0;
582 	if ((rse && rsr) || (rte && rto)) {
583 		/*
584 		 * Receive data on RSR to clear the STATS_RSR.
585 		 * Receive data on RTO, since we may not have yet hit the RSR
586 		 * watermark when we receive the RTO.
587 		 */
588 		for (i = 0, v = FIFO_RX_NDV;
589 		     (v & FIFO_RX_NDV) && !kror; i = 0) {
590 			for (j = 0;
591 			     (v & FIFO_RX_NDV) && j < FIFO_RX_DEPTH; j++) {
592 				v = cx25840_read4(c, CX25840_IR_FIFO_REG);
593 				rx_data[i].hw_fifo_data = v & ~FIFO_RX_NDV;
594 				i++;
595 			}
596 			if (i == 0)
597 				break;
598 			j = i * sizeof(union cx25840_ir_fifo_rec);
599 			k = kfifo_in_locked(&ir_state->rx_kfifo,
600 					    (unsigned char *) rx_data, j,
601 					    &ir_state->rx_kfifo_lock);
602 			if (k != j)
603 				kror++; /* rx_kfifo over run */
604 		}
605 		*handled = true;
606 	}
607 
608 	events = 0;
609 	v = 0;
610 	if (kror) {
611 		events |= V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN;
612 		v4l2_err(sd, "IR receiver software FIFO overrun\n");
613 	}
614 	if (roe && ror) {
615 		/*
616 		 * The RX FIFO Enable (CNTRL_RFE) must be toggled to clear
617 		 * the Rx FIFO Over Run status (STATS_ROR)
618 		 */
619 		v |= CNTRL_RFE;
620 		events |= V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN;
621 		v4l2_err(sd, "IR receiver hardware FIFO overrun\n");
622 	}
623 	if (rte && rto) {
624 		/*
625 		 * The IR Receiver Enable (CNTRL_RXE) must be toggled to clear
626 		 * the Rx Pulse Width Timer Time Out (STATS_RTO)
627 		 */
628 		v |= CNTRL_RXE;
629 		events |= V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED;
630 	}
631 	if (v) {
632 		/* Clear STATS_ROR & STATS_RTO as needed by resetting hardware */
633 		cx25840_write4(c, CX25840_IR_CNTRL_REG, cntrl & ~v);
634 		cx25840_write4(c, CX25840_IR_CNTRL_REG, cntrl);
635 		*handled = true;
636 	}
637 	spin_lock_irqsave(&ir_state->rx_kfifo_lock, flags);
638 	if (kfifo_len(&ir_state->rx_kfifo) >= CX25840_IR_RX_KFIFO_SIZE / 2)
639 		events |= V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ;
640 	spin_unlock_irqrestore(&ir_state->rx_kfifo_lock, flags);
641 
642 	if (events)
643 		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_RX_NOTIFY, &events);
644 	return 0;
645 }
646 
647 /* Receiver */
648 static int cx25840_ir_rx_read(struct v4l2_subdev *sd, u8 *buf, size_t count,
649 			      ssize_t *num)
650 {
651 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
652 	bool invert;
653 	u16 divider;
654 	unsigned int i, n;
655 	union cx25840_ir_fifo_rec *p;
656 	unsigned u, v, w;
657 
658 	if (ir_state == NULL)
659 		return -ENODEV;
660 
661 	invert = (bool) atomic_read(&ir_state->rx_invert);
662 	divider = (u16) atomic_read(&ir_state->rxclk_divider);
663 
664 	n = count / sizeof(union cx25840_ir_fifo_rec)
665 		* sizeof(union cx25840_ir_fifo_rec);
666 	if (n == 0) {
667 		*num = 0;
668 		return 0;
669 	}
670 
671 	n = kfifo_out_locked(&ir_state->rx_kfifo, buf, n,
672 			     &ir_state->rx_kfifo_lock);
673 
674 	n /= sizeof(union cx25840_ir_fifo_rec);
675 	*num = n * sizeof(union cx25840_ir_fifo_rec);
676 
677 	for (p = (union cx25840_ir_fifo_rec *) buf, i = 0; i < n; p++, i++) {
678 
679 		if ((p->hw_fifo_data & FIFO_RXTX_RTO) == FIFO_RXTX_RTO) {
680 			/* Assume RTO was because of no IR light input */
681 			u = 0;
682 			w = 1;
683 		} else {
684 			u = (p->hw_fifo_data & FIFO_RXTX_LVL) ? 1 : 0;
685 			if (invert)
686 				u = u ? 0 : 1;
687 			w = 0;
688 		}
689 
690 		v = (unsigned) pulse_width_count_to_ns(
691 				  (u16) (p->hw_fifo_data & FIFO_RXTX), divider);
692 		if (v > IR_MAX_DURATION)
693 			v = IR_MAX_DURATION;
694 
695 		p->ir_core_data = (struct ir_raw_event)
696 			{ .pulse = u, .duration = v, .timeout = w };
697 
698 		v4l2_dbg(2, ir_debug, sd, "rx read: %10u ns  %s  %s\n",
699 			 v, u ? "mark" : "space", w ? "(timed out)" : "");
700 		if (w)
701 			v4l2_dbg(2, ir_debug, sd, "rx read: end of rx\n");
702 	}
703 	return 0;
704 }
705 
706 static int cx25840_ir_rx_g_parameters(struct v4l2_subdev *sd,
707 				      struct v4l2_subdev_ir_parameters *p)
708 {
709 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
710 
711 	if (ir_state == NULL)
712 		return -ENODEV;
713 
714 	mutex_lock(&ir_state->rx_params_lock);
715 	memcpy(p, &ir_state->rx_params,
716 				      sizeof(struct v4l2_subdev_ir_parameters));
717 	mutex_unlock(&ir_state->rx_params_lock);
718 	return 0;
719 }
720 
721 static int cx25840_ir_rx_shutdown(struct v4l2_subdev *sd)
722 {
723 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
724 	struct i2c_client *c;
725 
726 	if (ir_state == NULL)
727 		return -ENODEV;
728 
729 	c = ir_state->c;
730 	mutex_lock(&ir_state->rx_params_lock);
731 
732 	/* Disable or slow down all IR Rx circuits and counters */
733 	irqenable_rx(sd, 0);
734 	control_rx_enable(c, false);
735 	control_rx_demodulation_enable(c, false);
736 	control_rx_s_edge_detection(c, CNTRL_EDG_NONE);
737 	filter_rx_s_min_width(c, 0);
738 	cx25840_write4(c, CX25840_IR_RXCLK_REG, RXCLK_RCD);
739 
740 	ir_state->rx_params.shutdown = true;
741 
742 	mutex_unlock(&ir_state->rx_params_lock);
743 	return 0;
744 }
745 
746 static int cx25840_ir_rx_s_parameters(struct v4l2_subdev *sd,
747 				      struct v4l2_subdev_ir_parameters *p)
748 {
749 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
750 	struct i2c_client *c;
751 	struct v4l2_subdev_ir_parameters *o;
752 	u16 rxclk_divider;
753 
754 	if (ir_state == NULL)
755 		return -ENODEV;
756 
757 	if (p->shutdown)
758 		return cx25840_ir_rx_shutdown(sd);
759 
760 	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
761 		return -ENOSYS;
762 
763 	c = ir_state->c;
764 	o = &ir_state->rx_params;
765 
766 	mutex_lock(&ir_state->rx_params_lock);
767 
768 	o->shutdown = p->shutdown;
769 
770 	p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
771 	o->mode = p->mode;
772 
773 	p->bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec);
774 	o->bytes_per_data_element = p->bytes_per_data_element;
775 
776 	/* Before we tweak the hardware, we have to disable the receiver */
777 	irqenable_rx(sd, 0);
778 	control_rx_enable(c, false);
779 
780 	control_rx_demodulation_enable(c, p->modulation);
781 	o->modulation = p->modulation;
782 
783 	if (p->modulation) {
784 		p->carrier_freq = rxclk_rx_s_carrier(c, p->carrier_freq,
785 						     &rxclk_divider);
786 
787 		o->carrier_freq = p->carrier_freq;
788 
789 		p->duty_cycle = 50;
790 		o->duty_cycle = p->duty_cycle;
791 
792 		control_rx_s_carrier_window(c, p->carrier_freq,
793 					    &p->carrier_range_lower,
794 					    &p->carrier_range_upper);
795 		o->carrier_range_lower = p->carrier_range_lower;
796 		o->carrier_range_upper = p->carrier_range_upper;
797 
798 		p->max_pulse_width =
799 			(u32) pulse_width_count_to_ns(FIFO_RXTX, rxclk_divider);
800 	} else {
801 		p->max_pulse_width =
802 			    rxclk_rx_s_max_pulse_width(c, p->max_pulse_width,
803 						       &rxclk_divider);
804 	}
805 	o->max_pulse_width = p->max_pulse_width;
806 	atomic_set(&ir_state->rxclk_divider, rxclk_divider);
807 
808 	p->noise_filter_min_width =
809 			    filter_rx_s_min_width(c, p->noise_filter_min_width);
810 	o->noise_filter_min_width = p->noise_filter_min_width;
811 
812 	p->resolution = clock_divider_to_resolution(rxclk_divider);
813 	o->resolution = p->resolution;
814 
815 	/* FIXME - make this dependent on resolution for better performance */
816 	control_rx_irq_watermark(c, RX_FIFO_HALF_FULL);
817 
818 	control_rx_s_edge_detection(c, CNTRL_EDG_BOTH);
819 
820 	o->invert_level = p->invert_level;
821 	atomic_set(&ir_state->rx_invert, p->invert_level);
822 
823 	o->interrupt_enable = p->interrupt_enable;
824 	o->enable = p->enable;
825 	if (p->enable) {
826 		unsigned long flags;
827 
828 		spin_lock_irqsave(&ir_state->rx_kfifo_lock, flags);
829 		kfifo_reset(&ir_state->rx_kfifo);
830 		spin_unlock_irqrestore(&ir_state->rx_kfifo_lock, flags);
831 		if (p->interrupt_enable)
832 			irqenable_rx(sd, IRQEN_RSE | IRQEN_RTE | IRQEN_ROE);
833 		control_rx_enable(c, p->enable);
834 	}
835 
836 	mutex_unlock(&ir_state->rx_params_lock);
837 	return 0;
838 }
839 
840 /* Transmitter */
841 static int cx25840_ir_tx_write(struct v4l2_subdev *sd, u8 *buf, size_t count,
842 			       ssize_t *num)
843 {
844 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
845 
846 	if (ir_state == NULL)
847 		return -ENODEV;
848 
849 #if 0
850 	/*
851 	 * FIXME - the code below is an incomplete and untested sketch of what
852 	 * may need to be done.  The critical part is to get 4 (or 8) pulses
853 	 * from the tx_kfifo, or converted from ns to the proper units from the
854 	 * input, and push them off to the hardware Tx FIFO right away, if the
855 	 * HW TX fifo needs service.  The rest can be pushed to the tx_kfifo in
856 	 * a less critical timeframe.  Also watch out for overruning the
857 	 * tx_kfifo - don't let it happen and let the caller know not all his
858 	 * pulses were written.
859 	 */
860 	u32 *ns_pulse = (u32 *) buf;
861 	unsigned int n;
862 	u32 fifo_pulse[FIFO_TX_DEPTH];
863 	u32 mark;
864 
865 	/* Compute how much we can fit in the tx kfifo */
866 	n = CX25840_IR_TX_KFIFO_SIZE - kfifo_len(ir_state->tx_kfifo);
867 	n = min(n, (unsigned int) count);
868 	n /= sizeof(u32);
869 
870 	/* FIXME - turn on Tx Fifo service interrupt
871 	 * check hardware fifo level, and other stuff
872 	 */
873 	for (i = 0; i < n; ) {
874 		for (j = 0; j < FIFO_TX_DEPTH / 2 && i < n; j++) {
875 			mark = ns_pulse[i] & LEVEL_MASK;
876 			fifo_pulse[j] = ns_to_pulse_width_count(
877 					 ns_pulse[i] &
878 					       ~LEVEL_MASK,
879 					 ir_state->txclk_divider);
880 			if (mark)
881 				fifo_pulse[j] &= FIFO_RXTX_LVL;
882 			i++;
883 		}
884 		kfifo_put(ir_state->tx_kfifo, (u8 *) fifo_pulse,
885 							       j * sizeof(u32));
886 	}
887 	*num = n * sizeof(u32);
888 #else
889 	/* For now enable the Tx FIFO Service interrupt & pretend we did work */
890 	irqenable_tx(sd, IRQEN_TSE);
891 	*num = count;
892 #endif
893 	return 0;
894 }
895 
896 static int cx25840_ir_tx_g_parameters(struct v4l2_subdev *sd,
897 				      struct v4l2_subdev_ir_parameters *p)
898 {
899 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
900 
901 	if (ir_state == NULL)
902 		return -ENODEV;
903 
904 	mutex_lock(&ir_state->tx_params_lock);
905 	memcpy(p, &ir_state->tx_params,
906 				      sizeof(struct v4l2_subdev_ir_parameters));
907 	mutex_unlock(&ir_state->tx_params_lock);
908 	return 0;
909 }
910 
911 static int cx25840_ir_tx_shutdown(struct v4l2_subdev *sd)
912 {
913 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
914 	struct i2c_client *c;
915 
916 	if (ir_state == NULL)
917 		return -ENODEV;
918 
919 	c = ir_state->c;
920 	mutex_lock(&ir_state->tx_params_lock);
921 
922 	/* Disable or slow down all IR Tx circuits and counters */
923 	irqenable_tx(sd, 0);
924 	control_tx_enable(c, false);
925 	control_tx_modulation_enable(c, false);
926 	cx25840_write4(c, CX25840_IR_TXCLK_REG, TXCLK_TCD);
927 
928 	ir_state->tx_params.shutdown = true;
929 
930 	mutex_unlock(&ir_state->tx_params_lock);
931 	return 0;
932 }
933 
934 static int cx25840_ir_tx_s_parameters(struct v4l2_subdev *sd,
935 				      struct v4l2_subdev_ir_parameters *p)
936 {
937 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
938 	struct i2c_client *c;
939 	struct v4l2_subdev_ir_parameters *o;
940 	u16 txclk_divider;
941 
942 	if (ir_state == NULL)
943 		return -ENODEV;
944 
945 	if (p->shutdown)
946 		return cx25840_ir_tx_shutdown(sd);
947 
948 	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
949 		return -ENOSYS;
950 
951 	c = ir_state->c;
952 	o = &ir_state->tx_params;
953 	mutex_lock(&ir_state->tx_params_lock);
954 
955 	o->shutdown = p->shutdown;
956 
957 	p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
958 	o->mode = p->mode;
959 
960 	p->bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec);
961 	o->bytes_per_data_element = p->bytes_per_data_element;
962 
963 	/* Before we tweak the hardware, we have to disable the transmitter */
964 	irqenable_tx(sd, 0);
965 	control_tx_enable(c, false);
966 
967 	control_tx_modulation_enable(c, p->modulation);
968 	o->modulation = p->modulation;
969 
970 	if (p->modulation) {
971 		p->carrier_freq = txclk_tx_s_carrier(c, p->carrier_freq,
972 						     &txclk_divider);
973 		o->carrier_freq = p->carrier_freq;
974 
975 		p->duty_cycle = cduty_tx_s_duty_cycle(c, p->duty_cycle);
976 		o->duty_cycle = p->duty_cycle;
977 
978 		p->max_pulse_width =
979 			(u32) pulse_width_count_to_ns(FIFO_RXTX, txclk_divider);
980 	} else {
981 		p->max_pulse_width =
982 			    txclk_tx_s_max_pulse_width(c, p->max_pulse_width,
983 						       &txclk_divider);
984 	}
985 	o->max_pulse_width = p->max_pulse_width;
986 	atomic_set(&ir_state->txclk_divider, txclk_divider);
987 
988 	p->resolution = clock_divider_to_resolution(txclk_divider);
989 	o->resolution = p->resolution;
990 
991 	/* FIXME - make this dependent on resolution for better performance */
992 	control_tx_irq_watermark(c, TX_FIFO_HALF_EMPTY);
993 
994 	control_tx_polarity_invert(c, p->invert_carrier_sense);
995 	o->invert_carrier_sense = p->invert_carrier_sense;
996 
997 	/*
998 	 * FIXME: we don't have hardware help for IO pin level inversion
999 	 * here like we have on the CX23888.
1000 	 * Act on this with some mix of logical inversion of data levels,
1001 	 * carrier polarity, and carrier duty cycle.
1002 	 */
1003 	o->invert_level = p->invert_level;
1004 
1005 	o->interrupt_enable = p->interrupt_enable;
1006 	o->enable = p->enable;
1007 	if (p->enable) {
1008 		/* reset tx_fifo here */
1009 		if (p->interrupt_enable)
1010 			irqenable_tx(sd, IRQEN_TSE);
1011 		control_tx_enable(c, p->enable);
1012 	}
1013 
1014 	mutex_unlock(&ir_state->tx_params_lock);
1015 	return 0;
1016 }
1017 
1018 
1019 /*
1020  * V4L2 Subdevice Core Ops support
1021  */
1022 int cx25840_ir_log_status(struct v4l2_subdev *sd)
1023 {
1024 	struct cx25840_state *state = to_state(sd);
1025 	struct i2c_client *c = state->c;
1026 	char *s;
1027 	int i, j;
1028 	u32 cntrl, txclk, rxclk, cduty, stats, irqen, filtr;
1029 
1030 	/* The CX23888 chip doesn't have an IR controller on the A/V core */
1031 	if (is_cx23888(state))
1032 		return 0;
1033 
1034 	cntrl = cx25840_read4(c, CX25840_IR_CNTRL_REG);
1035 	txclk = cx25840_read4(c, CX25840_IR_TXCLK_REG) & TXCLK_TCD;
1036 	rxclk = cx25840_read4(c, CX25840_IR_RXCLK_REG) & RXCLK_RCD;
1037 	cduty = cx25840_read4(c, CX25840_IR_CDUTY_REG) & CDUTY_CDC;
1038 	stats = cx25840_read4(c, CX25840_IR_STATS_REG);
1039 	irqen = cx25840_read4(c, CX25840_IR_IRQEN_REG);
1040 	if (is_cx23885(state) || is_cx23887(state))
1041 		irqen ^= IRQEN_MSK;
1042 	filtr = cx25840_read4(c, CX25840_IR_FILTR_REG) & FILTR_LPF;
1043 
1044 	v4l2_info(sd, "IR Receiver:\n");
1045 	v4l2_info(sd, "\tEnabled:                           %s\n",
1046 		  cntrl & CNTRL_RXE ? "yes" : "no");
1047 	v4l2_info(sd, "\tDemodulation from a carrier:       %s\n",
1048 		  cntrl & CNTRL_DMD ? "enabled" : "disabled");
1049 	v4l2_info(sd, "\tFIFO:                              %s\n",
1050 		  cntrl & CNTRL_RFE ? "enabled" : "disabled");
1051 	switch (cntrl & CNTRL_EDG) {
1052 	case CNTRL_EDG_NONE:
1053 		s = "disabled";
1054 		break;
1055 	case CNTRL_EDG_FALL:
1056 		s = "falling edge";
1057 		break;
1058 	case CNTRL_EDG_RISE:
1059 		s = "rising edge";
1060 		break;
1061 	case CNTRL_EDG_BOTH:
1062 		s = "rising & falling edges";
1063 		break;
1064 	default:
1065 		s = "??? edge";
1066 		break;
1067 	}
1068 	v4l2_info(sd, "\tPulse timers' start/stop trigger:  %s\n", s);
1069 	v4l2_info(sd, "\tFIFO data on pulse timer overflow: %s\n",
1070 		  cntrl & CNTRL_R ? "not loaded" : "overflow marker");
1071 	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1072 		  cntrl & CNTRL_RIC ? "not empty" : "half full or greater");
1073 	v4l2_info(sd, "\tLoopback mode:                     %s\n",
1074 		  cntrl & CNTRL_LBM ? "loopback active" : "normal receive");
1075 	if (cntrl & CNTRL_DMD) {
1076 		v4l2_info(sd, "\tExpected carrier (16 clocks):      %u Hz\n",
1077 			  clock_divider_to_carrier_freq(rxclk));
1078 		switch (cntrl & CNTRL_WIN) {
1079 		case CNTRL_WIN_3_3:
1080 			i = 3;
1081 			j = 3;
1082 			break;
1083 		case CNTRL_WIN_4_3:
1084 			i = 4;
1085 			j = 3;
1086 			break;
1087 		case CNTRL_WIN_3_4:
1088 			i = 3;
1089 			j = 4;
1090 			break;
1091 		case CNTRL_WIN_4_4:
1092 			i = 4;
1093 			j = 4;
1094 			break;
1095 		default:
1096 			i = 0;
1097 			j = 0;
1098 			break;
1099 		}
1100 		v4l2_info(sd, "\tNext carrier edge window:	    16 clocks -%1d/+%1d, %u to %u Hz\n",
1101 			  i, j,
1102 			  clock_divider_to_freq(rxclk, 16 + j),
1103 			  clock_divider_to_freq(rxclk, 16 - i));
1104 	}
1105 	v4l2_info(sd, "\tMax measurable pulse width:        %u us, %llu ns\n",
1106 		  pulse_width_count_to_us(FIFO_RXTX, rxclk),
1107 		  pulse_width_count_to_ns(FIFO_RXTX, rxclk));
1108 	v4l2_info(sd, "\tLow pass filter:                   %s\n",
1109 		  filtr ? "enabled" : "disabled");
1110 	if (filtr)
1111 		v4l2_info(sd, "\tMin acceptable pulse width (LPF):  %u us, %u ns\n",
1112 			  lpf_count_to_us(filtr),
1113 			  lpf_count_to_ns(filtr));
1114 	v4l2_info(sd, "\tPulse width timer timed-out:       %s\n",
1115 		  stats & STATS_RTO ? "yes" : "no");
1116 	v4l2_info(sd, "\tPulse width timer time-out intr:   %s\n",
1117 		  irqen & IRQEN_RTE ? "enabled" : "disabled");
1118 	v4l2_info(sd, "\tFIFO overrun:                      %s\n",
1119 		  stats & STATS_ROR ? "yes" : "no");
1120 	v4l2_info(sd, "\tFIFO overrun interrupt:            %s\n",
1121 		  irqen & IRQEN_ROE ? "enabled" : "disabled");
1122 	v4l2_info(sd, "\tBusy:                              %s\n",
1123 		  stats & STATS_RBY ? "yes" : "no");
1124 	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1125 		  stats & STATS_RSR ? "yes" : "no");
1126 	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1127 		  irqen & IRQEN_RSE ? "enabled" : "disabled");
1128 
1129 	v4l2_info(sd, "IR Transmitter:\n");
1130 	v4l2_info(sd, "\tEnabled:                           %s\n",
1131 		  cntrl & CNTRL_TXE ? "yes" : "no");
1132 	v4l2_info(sd, "\tModulation onto a carrier:         %s\n",
1133 		  cntrl & CNTRL_MOD ? "enabled" : "disabled");
1134 	v4l2_info(sd, "\tFIFO:                              %s\n",
1135 		  cntrl & CNTRL_TFE ? "enabled" : "disabled");
1136 	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1137 		  cntrl & CNTRL_TIC ? "not empty" : "half full or less");
1138 	v4l2_info(sd, "\tCarrier polarity:                  %s\n",
1139 		  cntrl & CNTRL_CPL ? "space:burst mark:noburst"
1140 				    : "space:noburst mark:burst");
1141 	if (cntrl & CNTRL_MOD) {
1142 		v4l2_info(sd, "\tCarrier (16 clocks):               %u Hz\n",
1143 			  clock_divider_to_carrier_freq(txclk));
1144 		v4l2_info(sd, "\tCarrier duty cycle:                %2u/16\n",
1145 			  cduty + 1);
1146 	}
1147 	v4l2_info(sd, "\tMax pulse width:                   %u us, %llu ns\n",
1148 		  pulse_width_count_to_us(FIFO_RXTX, txclk),
1149 		  pulse_width_count_to_ns(FIFO_RXTX, txclk));
1150 	v4l2_info(sd, "\tBusy:                              %s\n",
1151 		  stats & STATS_TBY ? "yes" : "no");
1152 	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1153 		  stats & STATS_TSR ? "yes" : "no");
1154 	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1155 		  irqen & IRQEN_TSE ? "enabled" : "disabled");
1156 
1157 	return 0;
1158 }
1159 
1160 
1161 const struct v4l2_subdev_ir_ops cx25840_ir_ops = {
1162 	.rx_read = cx25840_ir_rx_read,
1163 	.rx_g_parameters = cx25840_ir_rx_g_parameters,
1164 	.rx_s_parameters = cx25840_ir_rx_s_parameters,
1165 
1166 	.tx_write = cx25840_ir_tx_write,
1167 	.tx_g_parameters = cx25840_ir_tx_g_parameters,
1168 	.tx_s_parameters = cx25840_ir_tx_s_parameters,
1169 };
1170 
1171 
1172 static const struct v4l2_subdev_ir_parameters default_rx_params = {
1173 	.bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec),
1174 	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1175 
1176 	.enable = false,
1177 	.interrupt_enable = false,
1178 	.shutdown = true,
1179 
1180 	.modulation = true,
1181 	.carrier_freq = 36000, /* 36 kHz - RC-5, and RC-6 carrier */
1182 
1183 	/* RC-5: 666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
1184 	/* RC-6: 333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
1185 	.noise_filter_min_width = 333333, /* ns */
1186 	.carrier_range_lower = 35000,
1187 	.carrier_range_upper = 37000,
1188 	.invert_level = false,
1189 };
1190 
1191 static const struct v4l2_subdev_ir_parameters default_tx_params = {
1192 	.bytes_per_data_element = sizeof(union cx25840_ir_fifo_rec),
1193 	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1194 
1195 	.enable = false,
1196 	.interrupt_enable = false,
1197 	.shutdown = true,
1198 
1199 	.modulation = true,
1200 	.carrier_freq = 36000, /* 36 kHz - RC-5 carrier */
1201 	.duty_cycle = 25,      /* 25 %   - RC-5 carrier */
1202 	.invert_level = false,
1203 	.invert_carrier_sense = false,
1204 };
1205 
1206 int cx25840_ir_probe(struct v4l2_subdev *sd)
1207 {
1208 	struct cx25840_state *state = to_state(sd);
1209 	struct cx25840_ir_state *ir_state;
1210 	struct v4l2_subdev_ir_parameters default_params;
1211 
1212 	/* Only init the IR controller for the CX2388[57] AV Core for now */
1213 	if (!(is_cx23885(state) || is_cx23887(state)))
1214 		return 0;
1215 
1216 	ir_state = devm_kzalloc(&state->c->dev, sizeof(*ir_state), GFP_KERNEL);
1217 	if (ir_state == NULL)
1218 		return -ENOMEM;
1219 
1220 	spin_lock_init(&ir_state->rx_kfifo_lock);
1221 	if (kfifo_alloc(&ir_state->rx_kfifo,
1222 			CX25840_IR_RX_KFIFO_SIZE, GFP_KERNEL))
1223 		return -ENOMEM;
1224 
1225 	ir_state->c = state->c;
1226 	state->ir_state = ir_state;
1227 
1228 	/* Ensure no interrupts arrive yet */
1229 	if (is_cx23885(state) || is_cx23887(state))
1230 		cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, IRQEN_MSK);
1231 	else
1232 		cx25840_write4(ir_state->c, CX25840_IR_IRQEN_REG, 0);
1233 
1234 	mutex_init(&ir_state->rx_params_lock);
1235 	default_params = default_rx_params;
1236 	v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);
1237 
1238 	mutex_init(&ir_state->tx_params_lock);
1239 	default_params = default_tx_params;
1240 	v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
1241 
1242 	return 0;
1243 }
1244 
1245 int cx25840_ir_remove(struct v4l2_subdev *sd)
1246 {
1247 	struct cx25840_state *state = to_state(sd);
1248 	struct cx25840_ir_state *ir_state = to_ir_state(sd);
1249 
1250 	if (ir_state == NULL)
1251 		return -ENODEV;
1252 
1253 	cx25840_ir_rx_shutdown(sd);
1254 	cx25840_ir_tx_shutdown(sd);
1255 
1256 	kfifo_free(&ir_state->rx_kfifo);
1257 	state->ir_state = NULL;
1258 	return 0;
1259 }
1260