1 /*
2  *  Driver for the Conexant CX23885/7/8 PCIe bridge
3  *
4  *  CX23888 Integrated Consumer Infrared Controller
5  *
6  *  Copyright (C) 2009  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/kfifo.h>
25 #include <linux/slab.h>
26 
27 #include <media/v4l2-device.h>
28 #include <media/v4l2-chip-ident.h>
29 #include <media/rc-core.h>
30 
31 #include "cx23885.h"
32 #include "cx23888-ir.h"
33 
34 static unsigned int ir_888_debug;
35 module_param(ir_888_debug, int, 0644);
36 MODULE_PARM_DESC(ir_888_debug, "enable debug messages [CX23888 IR controller]");
37 
38 #define CX23888_IR_REG_BASE 	0x170000
39 /*
40  * These CX23888 register offsets have a straightforward one to one mapping
41  * to the CX23885 register offsets of 0x200 through 0x218
42  */
43 #define CX23888_IR_CNTRL_REG	0x170000
44 #define CNTRL_WIN_3_3	0x00000000
45 #define CNTRL_WIN_4_3	0x00000001
46 #define CNTRL_WIN_3_4	0x00000002
47 #define CNTRL_WIN_4_4	0x00000003
48 #define CNTRL_WIN	0x00000003
49 #define CNTRL_EDG_NONE	0x00000000
50 #define CNTRL_EDG_FALL	0x00000004
51 #define CNTRL_EDG_RISE	0x00000008
52 #define CNTRL_EDG_BOTH	0x0000000C
53 #define CNTRL_EDG	0x0000000C
54 #define CNTRL_DMD	0x00000010
55 #define CNTRL_MOD	0x00000020
56 #define CNTRL_RFE	0x00000040
57 #define CNTRL_TFE	0x00000080
58 #define CNTRL_RXE	0x00000100
59 #define CNTRL_TXE	0x00000200
60 #define CNTRL_RIC	0x00000400
61 #define CNTRL_TIC	0x00000800
62 #define CNTRL_CPL	0x00001000
63 #define CNTRL_LBM	0x00002000
64 #define CNTRL_R		0x00004000
65 /* CX23888 specific control flag */
66 #define CNTRL_IVO	0x00008000
67 
68 #define CX23888_IR_TXCLK_REG	0x170004
69 #define TXCLK_TCD	0x0000FFFF
70 
71 #define CX23888_IR_RXCLK_REG	0x170008
72 #define RXCLK_RCD	0x0000FFFF
73 
74 #define CX23888_IR_CDUTY_REG	0x17000C
75 #define CDUTY_CDC	0x0000000F
76 
77 #define CX23888_IR_STATS_REG	0x170010
78 #define STATS_RTO	0x00000001
79 #define STATS_ROR	0x00000002
80 #define STATS_RBY	0x00000004
81 #define STATS_TBY	0x00000008
82 #define STATS_RSR	0x00000010
83 #define STATS_TSR	0x00000020
84 
85 #define CX23888_IR_IRQEN_REG	0x170014
86 #define IRQEN_RTE	0x00000001
87 #define IRQEN_ROE	0x00000002
88 #define IRQEN_RSE	0x00000010
89 #define IRQEN_TSE	0x00000020
90 
91 #define CX23888_IR_FILTR_REG	0x170018
92 #define FILTR_LPF	0x0000FFFF
93 
94 /* This register doesn't follow the pattern; it's 0x23C on a CX23885 */
95 #define CX23888_IR_FIFO_REG	0x170040
96 #define FIFO_RXTX	0x0000FFFF
97 #define FIFO_RXTX_LVL	0x00010000
98 #define FIFO_RXTX_RTO	0x0001FFFF
99 #define FIFO_RX_NDV	0x00020000
100 #define FIFO_RX_DEPTH	8
101 #define FIFO_TX_DEPTH	8
102 
103 /* CX23888 unique registers */
104 #define CX23888_IR_SEEDP_REG	0x17001C
105 #define CX23888_IR_TIMOL_REG	0x170020
106 #define CX23888_IR_WAKE0_REG	0x170024
107 #define CX23888_IR_WAKE1_REG	0x170028
108 #define CX23888_IR_WAKE2_REG	0x17002C
109 #define CX23888_IR_MASK0_REG	0x170030
110 #define CX23888_IR_MASK1_REG	0x170034
111 #define CX23888_IR_MAKS2_REG	0x170038
112 #define CX23888_IR_DPIPG_REG	0x17003C
113 #define CX23888_IR_LEARN_REG	0x170044
114 
115 #define CX23888_VIDCLK_FREQ	108000000 /* 108 MHz, BT.656 */
116 #define CX23888_IR_REFCLK_FREQ	(CX23888_VIDCLK_FREQ / 2)
117 
118 /*
119  * We use this union internally for convenience, but callers to tx_write
120  * and rx_read will be expecting records of type struct ir_raw_event.
121  * Always ensure the size of this union is dictated by struct ir_raw_event.
122  */
123 union cx23888_ir_fifo_rec {
124 	u32 hw_fifo_data;
125 	struct ir_raw_event ir_core_data;
126 };
127 
128 #define CX23888_IR_RX_KFIFO_SIZE    (256 * sizeof(union cx23888_ir_fifo_rec))
129 #define CX23888_IR_TX_KFIFO_SIZE    (256 * sizeof(union cx23888_ir_fifo_rec))
130 
131 struct cx23888_ir_state {
132 	struct v4l2_subdev sd;
133 	struct cx23885_dev *dev;
134 	u32 id;
135 	u32 rev;
136 
137 	struct v4l2_subdev_ir_parameters rx_params;
138 	struct mutex rx_params_lock;
139 	atomic_t rxclk_divider;
140 	atomic_t rx_invert;
141 
142 	struct kfifo rx_kfifo;
143 	spinlock_t rx_kfifo_lock;
144 
145 	struct v4l2_subdev_ir_parameters tx_params;
146 	struct mutex tx_params_lock;
147 	atomic_t txclk_divider;
148 };
149 
150 static inline struct cx23888_ir_state *to_state(struct v4l2_subdev *sd)
151 {
152 	return v4l2_get_subdevdata(sd);
153 }
154 
155 /*
156  * IR register block read and write functions
157  */
158 static
159 inline int cx23888_ir_write4(struct cx23885_dev *dev, u32 addr, u32 value)
160 {
161 	cx_write(addr, value);
162 	return 0;
163 }
164 
165 static inline u32 cx23888_ir_read4(struct cx23885_dev *dev, u32 addr)
166 {
167 	return cx_read(addr);
168 }
169 
170 static inline int cx23888_ir_and_or4(struct cx23885_dev *dev, u32 addr,
171 				     u32 and_mask, u32 or_value)
172 {
173 	cx_andor(addr, ~and_mask, or_value);
174 	return 0;
175 }
176 
177 /*
178  * Rx and Tx Clock Divider register computations
179  *
180  * Note the largest clock divider value of 0xffff corresponds to:
181  * 	(0xffff + 1) * 1000 / 108/2 MHz = 1,213,629.629... ns
182  * which fits in 21 bits, so we'll use unsigned int for time arguments.
183  */
184 static inline u16 count_to_clock_divider(unsigned int d)
185 {
186 	if (d > RXCLK_RCD + 1)
187 		d = RXCLK_RCD;
188 	else if (d < 2)
189 		d = 1;
190 	else
191 		d--;
192 	return (u16) d;
193 }
194 
195 static inline u16 ns_to_clock_divider(unsigned int ns)
196 {
197 	return count_to_clock_divider(
198 		DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ / 1000000 * ns, 1000));
199 }
200 
201 static inline unsigned int clock_divider_to_ns(unsigned int divider)
202 {
203 	/* Period of the Rx or Tx clock in ns */
204 	return DIV_ROUND_CLOSEST((divider + 1) * 1000,
205 				 CX23888_IR_REFCLK_FREQ / 1000000);
206 }
207 
208 static inline u16 carrier_freq_to_clock_divider(unsigned int freq)
209 {
210 	return count_to_clock_divider(
211 			  DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ, freq * 16));
212 }
213 
214 static inline unsigned int clock_divider_to_carrier_freq(unsigned int divider)
215 {
216 	return DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ, (divider + 1) * 16);
217 }
218 
219 static inline u16 freq_to_clock_divider(unsigned int freq,
220 					unsigned int rollovers)
221 {
222 	return count_to_clock_divider(
223 		   DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ, freq * rollovers));
224 }
225 
226 static inline unsigned int clock_divider_to_freq(unsigned int divider,
227 						 unsigned int rollovers)
228 {
229 	return DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ,
230 				 (divider + 1) * rollovers);
231 }
232 
233 /*
234  * Low Pass Filter register calculations
235  *
236  * Note the largest count value of 0xffff corresponds to:
237  * 	0xffff * 1000 / 108/2 MHz = 1,213,611.11... ns
238  * which fits in 21 bits, so we'll use unsigned int for time arguments.
239  */
240 static inline u16 count_to_lpf_count(unsigned int d)
241 {
242 	if (d > FILTR_LPF)
243 		d = FILTR_LPF;
244 	else if (d < 4)
245 		d = 0;
246 	return (u16) d;
247 }
248 
249 static inline u16 ns_to_lpf_count(unsigned int ns)
250 {
251 	return count_to_lpf_count(
252 		DIV_ROUND_CLOSEST(CX23888_IR_REFCLK_FREQ / 1000000 * ns, 1000));
253 }
254 
255 static inline unsigned int lpf_count_to_ns(unsigned int count)
256 {
257 	/* Duration of the Low Pass Filter rejection window in ns */
258 	return DIV_ROUND_CLOSEST(count * 1000,
259 				 CX23888_IR_REFCLK_FREQ / 1000000);
260 }
261 
262 static inline unsigned int lpf_count_to_us(unsigned int count)
263 {
264 	/* Duration of the Low Pass Filter rejection window in us */
265 	return DIV_ROUND_CLOSEST(count, CX23888_IR_REFCLK_FREQ / 1000000);
266 }
267 
268 /*
269  * FIFO register pulse width count compuations
270  */
271 static u32 clock_divider_to_resolution(u16 divider)
272 {
273 	/*
274 	 * Resolution is the duration of 1 tick of the readable portion of
275 	 * of the pulse width counter as read from the FIFO.  The two lsb's are
276 	 * not readable, hence the << 2.  This function returns ns.
277 	 */
278 	return DIV_ROUND_CLOSEST((1 << 2)  * ((u32) divider + 1) * 1000,
279 				 CX23888_IR_REFCLK_FREQ / 1000000);
280 }
281 
282 static u64 pulse_width_count_to_ns(u16 count, u16 divider)
283 {
284 	u64 n;
285 	u32 rem;
286 
287 	/*
288 	 * The 2 lsb's of the pulse width timer count are not readable, hence
289 	 * the (count << 2) | 0x3
290 	 */
291 	n = (((u64) count << 2) | 0x3) * (divider + 1) * 1000; /* millicycles */
292 	rem = do_div(n, CX23888_IR_REFCLK_FREQ / 1000000);     /* / MHz => ns */
293 	if (rem >= CX23888_IR_REFCLK_FREQ / 1000000 / 2)
294 		n++;
295 	return n;
296 }
297 
298 static unsigned int pulse_width_count_to_us(u16 count, u16 divider)
299 {
300 	u64 n;
301 	u32 rem;
302 
303 	/*
304 	 * The 2 lsb's of the pulse width timer count are not readable, hence
305 	 * the (count << 2) | 0x3
306 	 */
307 	n = (((u64) count << 2) | 0x3) * (divider + 1);    /* cycles      */
308 	rem = do_div(n, CX23888_IR_REFCLK_FREQ / 1000000); /* / MHz => us */
309 	if (rem >= CX23888_IR_REFCLK_FREQ / 1000000 / 2)
310 		n++;
311 	return (unsigned int) n;
312 }
313 
314 /*
315  * Pulse Clocks computations: Combined Pulse Width Count & Rx Clock Counts
316  *
317  * The total pulse clock count is an 18 bit pulse width timer count as the most
318  * significant part and (up to) 16 bit clock divider count as a modulus.
319  * When the Rx clock divider ticks down to 0, it increments the 18 bit pulse
320  * width timer count's least significant bit.
321  */
322 static u64 ns_to_pulse_clocks(u32 ns)
323 {
324 	u64 clocks;
325 	u32 rem;
326 	clocks = CX23888_IR_REFCLK_FREQ / 1000000 * (u64) ns; /* millicycles  */
327 	rem = do_div(clocks, 1000);                         /* /1000 = cycles */
328 	if (rem >= 1000 / 2)
329 		clocks++;
330 	return clocks;
331 }
332 
333 static u16 pulse_clocks_to_clock_divider(u64 count)
334 {
335 	do_div(count, (FIFO_RXTX << 2) | 0x3);
336 
337 	/* net result needs to be rounded down and decremented by 1 */
338 	if (count > RXCLK_RCD + 1)
339 		count = RXCLK_RCD;
340 	else if (count < 2)
341 		count = 1;
342 	else
343 		count--;
344 	return (u16) count;
345 }
346 
347 /*
348  * IR Control Register helpers
349  */
350 enum tx_fifo_watermark {
351 	TX_FIFO_HALF_EMPTY = 0,
352 	TX_FIFO_EMPTY      = CNTRL_TIC,
353 };
354 
355 enum rx_fifo_watermark {
356 	RX_FIFO_HALF_FULL = 0,
357 	RX_FIFO_NOT_EMPTY = CNTRL_RIC,
358 };
359 
360 static inline void control_tx_irq_watermark(struct cx23885_dev *dev,
361 					    enum tx_fifo_watermark level)
362 {
363 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_TIC, level);
364 }
365 
366 static inline void control_rx_irq_watermark(struct cx23885_dev *dev,
367 					    enum rx_fifo_watermark level)
368 {
369 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_RIC, level);
370 }
371 
372 static inline void control_tx_enable(struct cx23885_dev *dev, bool enable)
373 {
374 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~(CNTRL_TXE | CNTRL_TFE),
375 			   enable ? (CNTRL_TXE | CNTRL_TFE) : 0);
376 }
377 
378 static inline void control_rx_enable(struct cx23885_dev *dev, bool enable)
379 {
380 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~(CNTRL_RXE | CNTRL_RFE),
381 			   enable ? (CNTRL_RXE | CNTRL_RFE) : 0);
382 }
383 
384 static inline void control_tx_modulation_enable(struct cx23885_dev *dev,
385 						bool enable)
386 {
387 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_MOD,
388 			   enable ? CNTRL_MOD : 0);
389 }
390 
391 static inline void control_rx_demodulation_enable(struct cx23885_dev *dev,
392 						  bool enable)
393 {
394 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_DMD,
395 			   enable ? CNTRL_DMD : 0);
396 }
397 
398 static inline void control_rx_s_edge_detection(struct cx23885_dev *dev,
399 					       u32 edge_types)
400 {
401 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_EDG_BOTH,
402 			   edge_types & CNTRL_EDG_BOTH);
403 }
404 
405 static void control_rx_s_carrier_window(struct cx23885_dev *dev,
406 					unsigned int carrier,
407 					unsigned int *carrier_range_low,
408 					unsigned int *carrier_range_high)
409 {
410 	u32 v;
411 	unsigned int c16 = carrier * 16;
412 
413 	if (*carrier_range_low < DIV_ROUND_CLOSEST(c16, 16 + 3)) {
414 		v = CNTRL_WIN_3_4;
415 		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 4);
416 	} else {
417 		v = CNTRL_WIN_3_3;
418 		*carrier_range_low = DIV_ROUND_CLOSEST(c16, 16 + 3);
419 	}
420 
421 	if (*carrier_range_high > DIV_ROUND_CLOSEST(c16, 16 - 3)) {
422 		v |= CNTRL_WIN_4_3;
423 		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 4);
424 	} else {
425 		v |= CNTRL_WIN_3_3;
426 		*carrier_range_high = DIV_ROUND_CLOSEST(c16, 16 - 3);
427 	}
428 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_WIN, v);
429 }
430 
431 static inline void control_tx_polarity_invert(struct cx23885_dev *dev,
432 					      bool invert)
433 {
434 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_CPL,
435 			   invert ? CNTRL_CPL : 0);
436 }
437 
438 static inline void control_tx_level_invert(struct cx23885_dev *dev,
439 					  bool invert)
440 {
441 	cx23888_ir_and_or4(dev, CX23888_IR_CNTRL_REG, ~CNTRL_IVO,
442 			   invert ? CNTRL_IVO : 0);
443 }
444 
445 /*
446  * IR Rx & Tx Clock Register helpers
447  */
448 static unsigned int txclk_tx_s_carrier(struct cx23885_dev *dev,
449 				       unsigned int freq,
450 				       u16 *divider)
451 {
452 	*divider = carrier_freq_to_clock_divider(freq);
453 	cx23888_ir_write4(dev, CX23888_IR_TXCLK_REG, *divider);
454 	return clock_divider_to_carrier_freq(*divider);
455 }
456 
457 static unsigned int rxclk_rx_s_carrier(struct cx23885_dev *dev,
458 				       unsigned int freq,
459 				       u16 *divider)
460 {
461 	*divider = carrier_freq_to_clock_divider(freq);
462 	cx23888_ir_write4(dev, CX23888_IR_RXCLK_REG, *divider);
463 	return clock_divider_to_carrier_freq(*divider);
464 }
465 
466 static u32 txclk_tx_s_max_pulse_width(struct cx23885_dev *dev, u32 ns,
467 				      u16 *divider)
468 {
469 	u64 pulse_clocks;
470 
471 	if (ns > IR_MAX_DURATION)
472 		ns = IR_MAX_DURATION;
473 	pulse_clocks = ns_to_pulse_clocks(ns);
474 	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
475 	cx23888_ir_write4(dev, CX23888_IR_TXCLK_REG, *divider);
476 	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
477 }
478 
479 static u32 rxclk_rx_s_max_pulse_width(struct cx23885_dev *dev, u32 ns,
480 				      u16 *divider)
481 {
482 	u64 pulse_clocks;
483 
484 	if (ns > IR_MAX_DURATION)
485 		ns = IR_MAX_DURATION;
486 	pulse_clocks = ns_to_pulse_clocks(ns);
487 	*divider = pulse_clocks_to_clock_divider(pulse_clocks);
488 	cx23888_ir_write4(dev, CX23888_IR_RXCLK_REG, *divider);
489 	return (u32) pulse_width_count_to_ns(FIFO_RXTX, *divider);
490 }
491 
492 /*
493  * IR Tx Carrier Duty Cycle register helpers
494  */
495 static unsigned int cduty_tx_s_duty_cycle(struct cx23885_dev *dev,
496 					  unsigned int duty_cycle)
497 {
498 	u32 n;
499 	n = DIV_ROUND_CLOSEST(duty_cycle * 100, 625); /* 16ths of 100% */
500 	if (n != 0)
501 		n--;
502 	if (n > 15)
503 		n = 15;
504 	cx23888_ir_write4(dev, CX23888_IR_CDUTY_REG, n);
505 	return DIV_ROUND_CLOSEST((n + 1) * 100, 16);
506 }
507 
508 /*
509  * IR Filter Register helpers
510  */
511 static u32 filter_rx_s_min_width(struct cx23885_dev *dev, u32 min_width_ns)
512 {
513 	u32 count = ns_to_lpf_count(min_width_ns);
514 	cx23888_ir_write4(dev, CX23888_IR_FILTR_REG, count);
515 	return lpf_count_to_ns(count);
516 }
517 
518 /*
519  * IR IRQ Enable Register helpers
520  */
521 static inline void irqenable_rx(struct cx23885_dev *dev, u32 mask)
522 {
523 	mask &= (IRQEN_RTE | IRQEN_ROE | IRQEN_RSE);
524 	cx23888_ir_and_or4(dev, CX23888_IR_IRQEN_REG,
525 			   ~(IRQEN_RTE | IRQEN_ROE | IRQEN_RSE), mask);
526 }
527 
528 static inline void irqenable_tx(struct cx23885_dev *dev, u32 mask)
529 {
530 	mask &= IRQEN_TSE;
531 	cx23888_ir_and_or4(dev, CX23888_IR_IRQEN_REG, ~IRQEN_TSE, mask);
532 }
533 
534 /*
535  * V4L2 Subdevice IR Ops
536  */
537 static int cx23888_ir_irq_handler(struct v4l2_subdev *sd, u32 status,
538 				  bool *handled)
539 {
540 	struct cx23888_ir_state *state = to_state(sd);
541 	struct cx23885_dev *dev = state->dev;
542 	unsigned long flags;
543 
544 	u32 cntrl = cx23888_ir_read4(dev, CX23888_IR_CNTRL_REG);
545 	u32 irqen = cx23888_ir_read4(dev, CX23888_IR_IRQEN_REG);
546 	u32 stats = cx23888_ir_read4(dev, CX23888_IR_STATS_REG);
547 
548 	union cx23888_ir_fifo_rec rx_data[FIFO_RX_DEPTH];
549 	unsigned int i, j, k;
550 	u32 events, v;
551 	int tsr, rsr, rto, ror, tse, rse, rte, roe, kror;
552 
553 	tsr = stats & STATS_TSR; /* Tx FIFO Service Request */
554 	rsr = stats & STATS_RSR; /* Rx FIFO Service Request */
555 	rto = stats & STATS_RTO; /* Rx Pulse Width Timer Time Out */
556 	ror = stats & STATS_ROR; /* Rx FIFO Over Run */
557 
558 	tse = irqen & IRQEN_TSE; /* Tx FIFO Service Request IRQ Enable */
559 	rse = irqen & IRQEN_RSE; /* Rx FIFO Service Reuqest IRQ Enable */
560 	rte = irqen & IRQEN_RTE; /* Rx Pulse Width Timer Time Out IRQ Enable */
561 	roe = irqen & IRQEN_ROE; /* Rx FIFO Over Run IRQ Enable */
562 
563 	*handled = false;
564 	v4l2_dbg(2, ir_888_debug, sd, "IRQ Status:  %s %s %s %s %s %s\n",
565 		 tsr ? "tsr" : "   ", rsr ? "rsr" : "   ",
566 		 rto ? "rto" : "   ", ror ? "ror" : "   ",
567 		 stats & STATS_TBY ? "tby" : "   ",
568 		 stats & STATS_RBY ? "rby" : "   ");
569 
570 	v4l2_dbg(2, ir_888_debug, sd, "IRQ Enables: %s %s %s %s\n",
571 		 tse ? "tse" : "   ", rse ? "rse" : "   ",
572 		 rte ? "rte" : "   ", roe ? "roe" : "   ");
573 
574 	/*
575 	 * Transmitter interrupt service
576 	 */
577 	if (tse && tsr) {
578 		/*
579 		 * TODO:
580 		 * Check the watermark threshold setting
581 		 * Pull FIFO_TX_DEPTH or FIFO_TX_DEPTH/2 entries from tx_kfifo
582 		 * Push the data to the hardware FIFO.
583 		 * If there was nothing more to send in the tx_kfifo, disable
584 		 *	the TSR IRQ and notify the v4l2_device.
585 		 * If there was something in the tx_kfifo, check the tx_kfifo
586 		 *      level and notify the v4l2_device, if it is low.
587 		 */
588 		/* For now, inhibit TSR interrupt until Tx is implemented */
589 		irqenable_tx(dev, 0);
590 		events = V4L2_SUBDEV_IR_TX_FIFO_SERVICE_REQ;
591 		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_TX_NOTIFY, &events);
592 		*handled = true;
593 	}
594 
595 	/*
596 	 * Receiver interrupt service
597 	 */
598 	kror = 0;
599 	if ((rse && rsr) || (rte && rto)) {
600 		/*
601 		 * Receive data on RSR to clear the STATS_RSR.
602 		 * Receive data on RTO, since we may not have yet hit the RSR
603 		 * watermark when we receive the RTO.
604 		 */
605 		for (i = 0, v = FIFO_RX_NDV;
606 		     (v & FIFO_RX_NDV) && !kror; i = 0) {
607 			for (j = 0;
608 			     (v & FIFO_RX_NDV) && j < FIFO_RX_DEPTH; j++) {
609 				v = cx23888_ir_read4(dev, CX23888_IR_FIFO_REG);
610 				rx_data[i].hw_fifo_data = v & ~FIFO_RX_NDV;
611 				i++;
612 			}
613 			if (i == 0)
614 				break;
615 			j = i * sizeof(union cx23888_ir_fifo_rec);
616 			k = kfifo_in_locked(&state->rx_kfifo,
617 				      (unsigned char *) rx_data, j,
618 				      &state->rx_kfifo_lock);
619 			if (k != j)
620 				kror++; /* rx_kfifo over run */
621 		}
622 		*handled = true;
623 	}
624 
625 	events = 0;
626 	v = 0;
627 	if (kror) {
628 		events |= V4L2_SUBDEV_IR_RX_SW_FIFO_OVERRUN;
629 		v4l2_err(sd, "IR receiver software FIFO overrun\n");
630 	}
631 	if (roe && ror) {
632 		/*
633 		 * The RX FIFO Enable (CNTRL_RFE) must be toggled to clear
634 		 * the Rx FIFO Over Run status (STATS_ROR)
635 		 */
636 		v |= CNTRL_RFE;
637 		events |= V4L2_SUBDEV_IR_RX_HW_FIFO_OVERRUN;
638 		v4l2_err(sd, "IR receiver hardware FIFO overrun\n");
639 	}
640 	if (rte && rto) {
641 		/*
642 		 * The IR Receiver Enable (CNTRL_RXE) must be toggled to clear
643 		 * the Rx Pulse Width Timer Time Out (STATS_RTO)
644 		 */
645 		v |= CNTRL_RXE;
646 		events |= V4L2_SUBDEV_IR_RX_END_OF_RX_DETECTED;
647 	}
648 	if (v) {
649 		/* Clear STATS_ROR & STATS_RTO as needed by reseting hardware */
650 		cx23888_ir_write4(dev, CX23888_IR_CNTRL_REG, cntrl & ~v);
651 		cx23888_ir_write4(dev, CX23888_IR_CNTRL_REG, cntrl);
652 		*handled = true;
653 	}
654 
655 	spin_lock_irqsave(&state->rx_kfifo_lock, flags);
656 	if (kfifo_len(&state->rx_kfifo) >= CX23888_IR_RX_KFIFO_SIZE / 2)
657 		events |= V4L2_SUBDEV_IR_RX_FIFO_SERVICE_REQ;
658 	spin_unlock_irqrestore(&state->rx_kfifo_lock, flags);
659 
660 	if (events)
661 		v4l2_subdev_notify(sd, V4L2_SUBDEV_IR_RX_NOTIFY, &events);
662 	return 0;
663 }
664 
665 /* Receiver */
666 static int cx23888_ir_rx_read(struct v4l2_subdev *sd, u8 *buf, size_t count,
667 			      ssize_t *num)
668 {
669 	struct cx23888_ir_state *state = to_state(sd);
670 	bool invert = (bool) atomic_read(&state->rx_invert);
671 	u16 divider = (u16) atomic_read(&state->rxclk_divider);
672 
673 	unsigned int i, n;
674 	union cx23888_ir_fifo_rec *p;
675 	unsigned u, v, w;
676 
677 	n = count / sizeof(union cx23888_ir_fifo_rec)
678 		* sizeof(union cx23888_ir_fifo_rec);
679 	if (n == 0) {
680 		*num = 0;
681 		return 0;
682 	}
683 
684 	n = kfifo_out_locked(&state->rx_kfifo, buf, n, &state->rx_kfifo_lock);
685 
686 	n /= sizeof(union cx23888_ir_fifo_rec);
687 	*num = n * sizeof(union cx23888_ir_fifo_rec);
688 
689 	for (p = (union cx23888_ir_fifo_rec *) buf, i = 0; i < n; p++, i++) {
690 
691 		if ((p->hw_fifo_data & FIFO_RXTX_RTO) == FIFO_RXTX_RTO) {
692 			/* Assume RTO was because of no IR light input */
693 			u = 0;
694 			w = 1;
695 		} else {
696 			u = (p->hw_fifo_data & FIFO_RXTX_LVL) ? 1 : 0;
697 			if (invert)
698 				u = u ? 0 : 1;
699 			w = 0;
700 		}
701 
702 		v = (unsigned) pulse_width_count_to_ns(
703 				  (u16) (p->hw_fifo_data & FIFO_RXTX), divider);
704 		if (v > IR_MAX_DURATION)
705 			v = IR_MAX_DURATION;
706 
707 		init_ir_raw_event(&p->ir_core_data);
708 		p->ir_core_data.pulse = u;
709 		p->ir_core_data.duration = v;
710 		p->ir_core_data.timeout = w;
711 
712 		v4l2_dbg(2, ir_888_debug, sd, "rx read: %10u ns  %s  %s\n",
713 			 v, u ? "mark" : "space", w ? "(timed out)" : "");
714 		if (w)
715 			v4l2_dbg(2, ir_888_debug, sd, "rx read: end of rx\n");
716 	}
717 	return 0;
718 }
719 
720 static int cx23888_ir_rx_g_parameters(struct v4l2_subdev *sd,
721 				      struct v4l2_subdev_ir_parameters *p)
722 {
723 	struct cx23888_ir_state *state = to_state(sd);
724 	mutex_lock(&state->rx_params_lock);
725 	memcpy(p, &state->rx_params, sizeof(struct v4l2_subdev_ir_parameters));
726 	mutex_unlock(&state->rx_params_lock);
727 	return 0;
728 }
729 
730 static int cx23888_ir_rx_shutdown(struct v4l2_subdev *sd)
731 {
732 	struct cx23888_ir_state *state = to_state(sd);
733 	struct cx23885_dev *dev = state->dev;
734 
735 	mutex_lock(&state->rx_params_lock);
736 
737 	/* Disable or slow down all IR Rx circuits and counters */
738 	irqenable_rx(dev, 0);
739 	control_rx_enable(dev, false);
740 	control_rx_demodulation_enable(dev, false);
741 	control_rx_s_edge_detection(dev, CNTRL_EDG_NONE);
742 	filter_rx_s_min_width(dev, 0);
743 	cx23888_ir_write4(dev, CX23888_IR_RXCLK_REG, RXCLK_RCD);
744 
745 	state->rx_params.shutdown = true;
746 
747 	mutex_unlock(&state->rx_params_lock);
748 	return 0;
749 }
750 
751 static int cx23888_ir_rx_s_parameters(struct v4l2_subdev *sd,
752 				      struct v4l2_subdev_ir_parameters *p)
753 {
754 	struct cx23888_ir_state *state = to_state(sd);
755 	struct cx23885_dev *dev = state->dev;
756 	struct v4l2_subdev_ir_parameters *o = &state->rx_params;
757 	u16 rxclk_divider;
758 
759 	if (p->shutdown)
760 		return cx23888_ir_rx_shutdown(sd);
761 
762 	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
763 		return -ENOSYS;
764 
765 	mutex_lock(&state->rx_params_lock);
766 
767 	o->shutdown = p->shutdown;
768 
769 	o->mode = p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
770 
771 	o->bytes_per_data_element = p->bytes_per_data_element
772 				  = sizeof(union cx23888_ir_fifo_rec);
773 
774 	/* Before we tweak the hardware, we have to disable the receiver */
775 	irqenable_rx(dev, 0);
776 	control_rx_enable(dev, false);
777 
778 	control_rx_demodulation_enable(dev, p->modulation);
779 	o->modulation = p->modulation;
780 
781 	if (p->modulation) {
782 		p->carrier_freq = rxclk_rx_s_carrier(dev, p->carrier_freq,
783 						     &rxclk_divider);
784 
785 		o->carrier_freq = p->carrier_freq;
786 
787 		o->duty_cycle = p->duty_cycle = 50;
788 
789 		control_rx_s_carrier_window(dev, p->carrier_freq,
790 					    &p->carrier_range_lower,
791 					    &p->carrier_range_upper);
792 		o->carrier_range_lower = p->carrier_range_lower;
793 		o->carrier_range_upper = p->carrier_range_upper;
794 
795 		p->max_pulse_width =
796 			(u32) pulse_width_count_to_ns(FIFO_RXTX, rxclk_divider);
797 	} else {
798 		p->max_pulse_width =
799 			    rxclk_rx_s_max_pulse_width(dev, p->max_pulse_width,
800 						       &rxclk_divider);
801 	}
802 	o->max_pulse_width = p->max_pulse_width;
803 	atomic_set(&state->rxclk_divider, rxclk_divider);
804 
805 	p->noise_filter_min_width =
806 			  filter_rx_s_min_width(dev, p->noise_filter_min_width);
807 	o->noise_filter_min_width = p->noise_filter_min_width;
808 
809 	p->resolution = clock_divider_to_resolution(rxclk_divider);
810 	o->resolution = p->resolution;
811 
812 	/* FIXME - make this dependent on resolution for better performance */
813 	control_rx_irq_watermark(dev, RX_FIFO_HALF_FULL);
814 
815 	control_rx_s_edge_detection(dev, CNTRL_EDG_BOTH);
816 
817 	o->invert_level = p->invert_level;
818 	atomic_set(&state->rx_invert, p->invert_level);
819 
820 	o->interrupt_enable = p->interrupt_enable;
821 	o->enable = p->enable;
822 	if (p->enable) {
823 		unsigned long flags;
824 
825 		spin_lock_irqsave(&state->rx_kfifo_lock, flags);
826 		kfifo_reset(&state->rx_kfifo);
827 		/* reset tx_fifo too if there is one... */
828 		spin_unlock_irqrestore(&state->rx_kfifo_lock, flags);
829 		if (p->interrupt_enable)
830 			irqenable_rx(dev, IRQEN_RSE | IRQEN_RTE | IRQEN_ROE);
831 		control_rx_enable(dev, p->enable);
832 	}
833 
834 	mutex_unlock(&state->rx_params_lock);
835 	return 0;
836 }
837 
838 /* Transmitter */
839 static int cx23888_ir_tx_write(struct v4l2_subdev *sd, u8 *buf, size_t count,
840 			       ssize_t *num)
841 {
842 	struct cx23888_ir_state *state = to_state(sd);
843 	struct cx23885_dev *dev = state->dev;
844 	/* For now enable the Tx FIFO Service interrupt & pretend we did work */
845 	irqenable_tx(dev, IRQEN_TSE);
846 	*num = count;
847 	return 0;
848 }
849 
850 static int cx23888_ir_tx_g_parameters(struct v4l2_subdev *sd,
851 				      struct v4l2_subdev_ir_parameters *p)
852 {
853 	struct cx23888_ir_state *state = to_state(sd);
854 	mutex_lock(&state->tx_params_lock);
855 	memcpy(p, &state->tx_params, sizeof(struct v4l2_subdev_ir_parameters));
856 	mutex_unlock(&state->tx_params_lock);
857 	return 0;
858 }
859 
860 static int cx23888_ir_tx_shutdown(struct v4l2_subdev *sd)
861 {
862 	struct cx23888_ir_state *state = to_state(sd);
863 	struct cx23885_dev *dev = state->dev;
864 
865 	mutex_lock(&state->tx_params_lock);
866 
867 	/* Disable or slow down all IR Tx circuits and counters */
868 	irqenable_tx(dev, 0);
869 	control_tx_enable(dev, false);
870 	control_tx_modulation_enable(dev, false);
871 	cx23888_ir_write4(dev, CX23888_IR_TXCLK_REG, TXCLK_TCD);
872 
873 	state->tx_params.shutdown = true;
874 
875 	mutex_unlock(&state->tx_params_lock);
876 	return 0;
877 }
878 
879 static int cx23888_ir_tx_s_parameters(struct v4l2_subdev *sd,
880 				      struct v4l2_subdev_ir_parameters *p)
881 {
882 	struct cx23888_ir_state *state = to_state(sd);
883 	struct cx23885_dev *dev = state->dev;
884 	struct v4l2_subdev_ir_parameters *o = &state->tx_params;
885 	u16 txclk_divider;
886 
887 	if (p->shutdown)
888 		return cx23888_ir_tx_shutdown(sd);
889 
890 	if (p->mode != V4L2_SUBDEV_IR_MODE_PULSE_WIDTH)
891 		return -ENOSYS;
892 
893 	mutex_lock(&state->tx_params_lock);
894 
895 	o->shutdown = p->shutdown;
896 
897 	o->mode = p->mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH;
898 
899 	o->bytes_per_data_element = p->bytes_per_data_element
900 				  = sizeof(union cx23888_ir_fifo_rec);
901 
902 	/* Before we tweak the hardware, we have to disable the transmitter */
903 	irqenable_tx(dev, 0);
904 	control_tx_enable(dev, false);
905 
906 	control_tx_modulation_enable(dev, p->modulation);
907 	o->modulation = p->modulation;
908 
909 	if (p->modulation) {
910 		p->carrier_freq = txclk_tx_s_carrier(dev, p->carrier_freq,
911 						     &txclk_divider);
912 		o->carrier_freq = p->carrier_freq;
913 
914 		p->duty_cycle = cduty_tx_s_duty_cycle(dev, p->duty_cycle);
915 		o->duty_cycle = p->duty_cycle;
916 
917 		p->max_pulse_width =
918 			(u32) pulse_width_count_to_ns(FIFO_RXTX, txclk_divider);
919 	} else {
920 		p->max_pulse_width =
921 			    txclk_tx_s_max_pulse_width(dev, p->max_pulse_width,
922 						       &txclk_divider);
923 	}
924 	o->max_pulse_width = p->max_pulse_width;
925 	atomic_set(&state->txclk_divider, txclk_divider);
926 
927 	p->resolution = clock_divider_to_resolution(txclk_divider);
928 	o->resolution = p->resolution;
929 
930 	/* FIXME - make this dependent on resolution for better performance */
931 	control_tx_irq_watermark(dev, TX_FIFO_HALF_EMPTY);
932 
933 	control_tx_polarity_invert(dev, p->invert_carrier_sense);
934 	o->invert_carrier_sense = p->invert_carrier_sense;
935 
936 	control_tx_level_invert(dev, p->invert_level);
937 	o->invert_level = p->invert_level;
938 
939 	o->interrupt_enable = p->interrupt_enable;
940 	o->enable = p->enable;
941 	if (p->enable) {
942 		if (p->interrupt_enable)
943 			irqenable_tx(dev, IRQEN_TSE);
944 		control_tx_enable(dev, p->enable);
945 	}
946 
947 	mutex_unlock(&state->tx_params_lock);
948 	return 0;
949 }
950 
951 
952 /*
953  * V4L2 Subdevice Core Ops
954  */
955 static int cx23888_ir_log_status(struct v4l2_subdev *sd)
956 {
957 	struct cx23888_ir_state *state = to_state(sd);
958 	struct cx23885_dev *dev = state->dev;
959 	char *s;
960 	int i, j;
961 
962 	u32 cntrl = cx23888_ir_read4(dev, CX23888_IR_CNTRL_REG);
963 	u32 txclk = cx23888_ir_read4(dev, CX23888_IR_TXCLK_REG) & TXCLK_TCD;
964 	u32 rxclk = cx23888_ir_read4(dev, CX23888_IR_RXCLK_REG) & RXCLK_RCD;
965 	u32 cduty = cx23888_ir_read4(dev, CX23888_IR_CDUTY_REG) & CDUTY_CDC;
966 	u32 stats = cx23888_ir_read4(dev, CX23888_IR_STATS_REG);
967 	u32 irqen = cx23888_ir_read4(dev, CX23888_IR_IRQEN_REG);
968 	u32 filtr = cx23888_ir_read4(dev, CX23888_IR_FILTR_REG) & FILTR_LPF;
969 
970 	v4l2_info(sd, "IR Receiver:\n");
971 	v4l2_info(sd, "\tEnabled:                           %s\n",
972 		  cntrl & CNTRL_RXE ? "yes" : "no");
973 	v4l2_info(sd, "\tDemodulation from a carrier:       %s\n",
974 		  cntrl & CNTRL_DMD ? "enabled" : "disabled");
975 	v4l2_info(sd, "\tFIFO:                              %s\n",
976 		  cntrl & CNTRL_RFE ? "enabled" : "disabled");
977 	switch (cntrl & CNTRL_EDG) {
978 	case CNTRL_EDG_NONE:
979 		s = "disabled";
980 		break;
981 	case CNTRL_EDG_FALL:
982 		s = "falling edge";
983 		break;
984 	case CNTRL_EDG_RISE:
985 		s = "rising edge";
986 		break;
987 	case CNTRL_EDG_BOTH:
988 		s = "rising & falling edges";
989 		break;
990 	default:
991 		s = "??? edge";
992 		break;
993 	}
994 	v4l2_info(sd, "\tPulse timers' start/stop trigger:  %s\n", s);
995 	v4l2_info(sd, "\tFIFO data on pulse timer overflow: %s\n",
996 		  cntrl & CNTRL_R ? "not loaded" : "overflow marker");
997 	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
998 		  cntrl & CNTRL_RIC ? "not empty" : "half full or greater");
999 	v4l2_info(sd, "\tLoopback mode:                     %s\n",
1000 		  cntrl & CNTRL_LBM ? "loopback active" : "normal receive");
1001 	if (cntrl & CNTRL_DMD) {
1002 		v4l2_info(sd, "\tExpected carrier (16 clocks):      %u Hz\n",
1003 			  clock_divider_to_carrier_freq(rxclk));
1004 		switch (cntrl & CNTRL_WIN) {
1005 		case CNTRL_WIN_3_3:
1006 			i = 3;
1007 			j = 3;
1008 			break;
1009 		case CNTRL_WIN_4_3:
1010 			i = 4;
1011 			j = 3;
1012 			break;
1013 		case CNTRL_WIN_3_4:
1014 			i = 3;
1015 			j = 4;
1016 			break;
1017 		case CNTRL_WIN_4_4:
1018 			i = 4;
1019 			j = 4;
1020 			break;
1021 		default:
1022 			i = 0;
1023 			j = 0;
1024 			break;
1025 		}
1026 		v4l2_info(sd, "\tNext carrier edge window:          16 clocks "
1027 			  "-%1d/+%1d, %u to %u Hz\n", i, j,
1028 			  clock_divider_to_freq(rxclk, 16 + j),
1029 			  clock_divider_to_freq(rxclk, 16 - i));
1030 	}
1031 	v4l2_info(sd, "\tMax measurable pulse width:        %u us, %llu ns\n",
1032 		  pulse_width_count_to_us(FIFO_RXTX, rxclk),
1033 		  pulse_width_count_to_ns(FIFO_RXTX, rxclk));
1034 	v4l2_info(sd, "\tLow pass filter:                   %s\n",
1035 		  filtr ? "enabled" : "disabled");
1036 	if (filtr)
1037 		v4l2_info(sd, "\tMin acceptable pulse width (LPF):  %u us, "
1038 			  "%u ns\n",
1039 			  lpf_count_to_us(filtr),
1040 			  lpf_count_to_ns(filtr));
1041 	v4l2_info(sd, "\tPulse width timer timed-out:       %s\n",
1042 		  stats & STATS_RTO ? "yes" : "no");
1043 	v4l2_info(sd, "\tPulse width timer time-out intr:   %s\n",
1044 		  irqen & IRQEN_RTE ? "enabled" : "disabled");
1045 	v4l2_info(sd, "\tFIFO overrun:                      %s\n",
1046 		  stats & STATS_ROR ? "yes" : "no");
1047 	v4l2_info(sd, "\tFIFO overrun interrupt:            %s\n",
1048 		  irqen & IRQEN_ROE ? "enabled" : "disabled");
1049 	v4l2_info(sd, "\tBusy:                              %s\n",
1050 		  stats & STATS_RBY ? "yes" : "no");
1051 	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1052 		  stats & STATS_RSR ? "yes" : "no");
1053 	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1054 		  irqen & IRQEN_RSE ? "enabled" : "disabled");
1055 
1056 	v4l2_info(sd, "IR Transmitter:\n");
1057 	v4l2_info(sd, "\tEnabled:                           %s\n",
1058 		  cntrl & CNTRL_TXE ? "yes" : "no");
1059 	v4l2_info(sd, "\tModulation onto a carrier:         %s\n",
1060 		  cntrl & CNTRL_MOD ? "enabled" : "disabled");
1061 	v4l2_info(sd, "\tFIFO:                              %s\n",
1062 		  cntrl & CNTRL_TFE ? "enabled" : "disabled");
1063 	v4l2_info(sd, "\tFIFO interrupt watermark:          %s\n",
1064 		  cntrl & CNTRL_TIC ? "not empty" : "half full or less");
1065 	v4l2_info(sd, "\tOutput pin level inversion         %s\n",
1066 		  cntrl & CNTRL_IVO ? "yes" : "no");
1067 	v4l2_info(sd, "\tCarrier polarity:                  %s\n",
1068 		  cntrl & CNTRL_CPL ? "space:burst mark:noburst"
1069 				    : "space:noburst mark:burst");
1070 	if (cntrl & CNTRL_MOD) {
1071 		v4l2_info(sd, "\tCarrier (16 clocks):               %u Hz\n",
1072 			  clock_divider_to_carrier_freq(txclk));
1073 		v4l2_info(sd, "\tCarrier duty cycle:                %2u/16\n",
1074 			  cduty + 1);
1075 	}
1076 	v4l2_info(sd, "\tMax pulse width:                   %u us, %llu ns\n",
1077 		  pulse_width_count_to_us(FIFO_RXTX, txclk),
1078 		  pulse_width_count_to_ns(FIFO_RXTX, txclk));
1079 	v4l2_info(sd, "\tBusy:                              %s\n",
1080 		  stats & STATS_TBY ? "yes" : "no");
1081 	v4l2_info(sd, "\tFIFO service requested:            %s\n",
1082 		  stats & STATS_TSR ? "yes" : "no");
1083 	v4l2_info(sd, "\tFIFO service request interrupt:    %s\n",
1084 		  irqen & IRQEN_TSE ? "enabled" : "disabled");
1085 
1086 	return 0;
1087 }
1088 
1089 static inline int cx23888_ir_dbg_match(const struct v4l2_dbg_match *match)
1090 {
1091 	return match->type == V4L2_CHIP_MATCH_HOST && match->addr == 2;
1092 }
1093 
1094 static int cx23888_ir_g_chip_ident(struct v4l2_subdev *sd,
1095 				   struct v4l2_dbg_chip_ident *chip)
1096 {
1097 	struct cx23888_ir_state *state = to_state(sd);
1098 
1099 	if (cx23888_ir_dbg_match(&chip->match)) {
1100 		chip->ident = state->id;
1101 		chip->revision = state->rev;
1102 	}
1103 	return 0;
1104 }
1105 
1106 #ifdef CONFIG_VIDEO_ADV_DEBUG
1107 static int cx23888_ir_g_register(struct v4l2_subdev *sd,
1108 				 struct v4l2_dbg_register *reg)
1109 {
1110 	struct cx23888_ir_state *state = to_state(sd);
1111 	u32 addr = CX23888_IR_REG_BASE + (u32) reg->reg;
1112 
1113 	if (!cx23888_ir_dbg_match(&reg->match))
1114 		return -EINVAL;
1115 	if ((addr & 0x3) != 0)
1116 		return -EINVAL;
1117 	if (addr < CX23888_IR_CNTRL_REG || addr > CX23888_IR_LEARN_REG)
1118 		return -EINVAL;
1119 	if (!capable(CAP_SYS_ADMIN))
1120 		return -EPERM;
1121 	reg->size = 4;
1122 	reg->val = cx23888_ir_read4(state->dev, addr);
1123 	return 0;
1124 }
1125 
1126 static int cx23888_ir_s_register(struct v4l2_subdev *sd,
1127 				 const struct v4l2_dbg_register *reg)
1128 {
1129 	struct cx23888_ir_state *state = to_state(sd);
1130 	u32 addr = CX23888_IR_REG_BASE + (u32) reg->reg;
1131 
1132 	if (!cx23888_ir_dbg_match(&reg->match))
1133 		return -EINVAL;
1134 	if ((addr & 0x3) != 0)
1135 		return -EINVAL;
1136 	if (addr < CX23888_IR_CNTRL_REG || addr > CX23888_IR_LEARN_REG)
1137 		return -EINVAL;
1138 	if (!capable(CAP_SYS_ADMIN))
1139 		return -EPERM;
1140 	cx23888_ir_write4(state->dev, addr, reg->val);
1141 	return 0;
1142 }
1143 #endif
1144 
1145 static const struct v4l2_subdev_core_ops cx23888_ir_core_ops = {
1146 	.g_chip_ident = cx23888_ir_g_chip_ident,
1147 	.log_status = cx23888_ir_log_status,
1148 #ifdef CONFIG_VIDEO_ADV_DEBUG
1149 	.g_register = cx23888_ir_g_register,
1150 	.s_register = cx23888_ir_s_register,
1151 #endif
1152 	.interrupt_service_routine = cx23888_ir_irq_handler,
1153 };
1154 
1155 static const struct v4l2_subdev_ir_ops cx23888_ir_ir_ops = {
1156 	.rx_read = cx23888_ir_rx_read,
1157 	.rx_g_parameters = cx23888_ir_rx_g_parameters,
1158 	.rx_s_parameters = cx23888_ir_rx_s_parameters,
1159 
1160 	.tx_write = cx23888_ir_tx_write,
1161 	.tx_g_parameters = cx23888_ir_tx_g_parameters,
1162 	.tx_s_parameters = cx23888_ir_tx_s_parameters,
1163 };
1164 
1165 static const struct v4l2_subdev_ops cx23888_ir_controller_ops = {
1166 	.core = &cx23888_ir_core_ops,
1167 	.ir = &cx23888_ir_ir_ops,
1168 };
1169 
1170 static const struct v4l2_subdev_ir_parameters default_rx_params = {
1171 	.bytes_per_data_element = sizeof(union cx23888_ir_fifo_rec),
1172 	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1173 
1174 	.enable = false,
1175 	.interrupt_enable = false,
1176 	.shutdown = true,
1177 
1178 	.modulation = true,
1179 	.carrier_freq = 36000, /* 36 kHz - RC-5, RC-6, and RC-6A carrier */
1180 
1181 	/* RC-5:    666,667 ns = 1/36 kHz * 32 cycles * 1 mark * 0.75 */
1182 	/* RC-6A:   333,333 ns = 1/36 kHz * 16 cycles * 1 mark * 0.75 */
1183 	.noise_filter_min_width = 333333, /* ns */
1184 	.carrier_range_lower = 35000,
1185 	.carrier_range_upper = 37000,
1186 	.invert_level = false,
1187 };
1188 
1189 static const struct v4l2_subdev_ir_parameters default_tx_params = {
1190 	.bytes_per_data_element = sizeof(union cx23888_ir_fifo_rec),
1191 	.mode = V4L2_SUBDEV_IR_MODE_PULSE_WIDTH,
1192 
1193 	.enable = false,
1194 	.interrupt_enable = false,
1195 	.shutdown = true,
1196 
1197 	.modulation = true,
1198 	.carrier_freq = 36000, /* 36 kHz - RC-5 carrier */
1199 	.duty_cycle = 25,      /* 25 %   - RC-5 carrier */
1200 	.invert_level = false,
1201 	.invert_carrier_sense = false,
1202 };
1203 
1204 int cx23888_ir_probe(struct cx23885_dev *dev)
1205 {
1206 	struct cx23888_ir_state *state;
1207 	struct v4l2_subdev *sd;
1208 	struct v4l2_subdev_ir_parameters default_params;
1209 	int ret;
1210 
1211 	state = kzalloc(sizeof(struct cx23888_ir_state), GFP_KERNEL);
1212 	if (state == NULL)
1213 		return -ENOMEM;
1214 
1215 	spin_lock_init(&state->rx_kfifo_lock);
1216 	if (kfifo_alloc(&state->rx_kfifo, CX23888_IR_RX_KFIFO_SIZE, GFP_KERNEL))
1217 		return -ENOMEM;
1218 
1219 	state->dev = dev;
1220 	state->id = V4L2_IDENT_CX23888_IR;
1221 	state->rev = 0;
1222 	sd = &state->sd;
1223 
1224 	v4l2_subdev_init(sd, &cx23888_ir_controller_ops);
1225 	v4l2_set_subdevdata(sd, state);
1226 	/* FIXME - fix the formatting of dev->v4l2_dev.name and use it */
1227 	snprintf(sd->name, sizeof(sd->name), "%s/888-ir", dev->name);
1228 	sd->grp_id = CX23885_HW_888_IR;
1229 
1230 	ret = v4l2_device_register_subdev(&dev->v4l2_dev, sd);
1231 	if (ret == 0) {
1232 		/*
1233 		 * Ensure no interrupts arrive from '888 specific conditions,
1234 		 * since we ignore them in this driver to have commonality with
1235 		 * similar IR controller cores.
1236 		 */
1237 		cx23888_ir_write4(dev, CX23888_IR_IRQEN_REG, 0);
1238 
1239 		mutex_init(&state->rx_params_lock);
1240 		default_params = default_rx_params;
1241 		v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);
1242 
1243 		mutex_init(&state->tx_params_lock);
1244 		default_params = default_tx_params;
1245 		v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
1246 	} else {
1247 		kfifo_free(&state->rx_kfifo);
1248 	}
1249 	return ret;
1250 }
1251 
1252 int cx23888_ir_remove(struct cx23885_dev *dev)
1253 {
1254 	struct v4l2_subdev *sd;
1255 	struct cx23888_ir_state *state;
1256 
1257 	sd = cx23885_find_hw(dev, CX23885_HW_888_IR);
1258 	if (sd == NULL)
1259 		return -ENODEV;
1260 
1261 	cx23888_ir_rx_shutdown(sd);
1262 	cx23888_ir_tx_shutdown(sd);
1263 
1264 	state = to_state(sd);
1265 	v4l2_device_unregister_subdev(sd);
1266 	kfifo_free(&state->rx_kfifo);
1267 	kfree(state);
1268 	/* Nothing more to free() as state held the actual v4l2_subdev object */
1269 	return 0;
1270 }
1271