xref: /linux/drivers/media/pci/cx18/cx18-av-audio.c (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  cx18 ADEC audio functions
4  *
5  *  Derived from cx25840-audio.c
6  *
7  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
8  *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.net>
9  */
10 
11 #include "cx18-driver.h"
12 
set_audclk_freq(struct cx18 * cx,u32 freq)13 static int set_audclk_freq(struct cx18 *cx, u32 freq)
14 {
15 	struct cx18_av_state *state = &cx->av_state;
16 
17 	if (freq != 32000 && freq != 44100 && freq != 48000)
18 		return -EINVAL;
19 
20 	/*
21 	 * The PLL parameters are based on the external crystal frequency that
22 	 * would ideally be:
23 	 *
24 	 * NTSC Color subcarrier freq * 8 =
25 	 *	4.5 MHz/286 * 455/2 * 8 = 28.63636363... MHz
26 	 *
27 	 * The accidents of history and rationale that explain from where this
28 	 * combination of magic numbers originate can be found in:
29 	 *
30 	 * [1] Abrahams, I. C., "Choice of Chrominance Subcarrier Frequency in
31 	 * the NTSC Standards", Proceedings of the I-R-E, January 1954, pp 79-80
32 	 *
33 	 * [2] Abrahams, I. C., "The 'Frequency Interleaving' Principle in the
34 	 * NTSC Standards", Proceedings of the I-R-E, January 1954, pp 81-83
35 	 *
36 	 * As Mike Bradley has rightly pointed out, it's not the exact crystal
37 	 * frequency that matters, only that all parts of the driver and
38 	 * firmware are using the same value (close to the ideal value).
39 	 *
40 	 * Since I have a strong suspicion that, if the firmware ever assumes a
41 	 * crystal value at all, it will assume 28.636360 MHz, the crystal
42 	 * freq used in calculations in this driver will be:
43 	 *
44 	 *	xtal_freq = 28.636360 MHz
45 	 *
46 	 * an error of less than 0.13 ppm which is way, way better than any off
47 	 * the shelf crystal will have for accuracy anyway.
48 	 *
49 	 * Below I aim to run the PLLs' VCOs near 400 MHz to minimize error.
50 	 *
51 	 * Many thanks to Jeff Campbell and Mike Bradley for their extensive
52 	 * investigation, experimentation, testing, and suggested solutions of
53 	 * audio/video sync problems with SVideo and CVBS captures.
54 	 */
55 
56 	if (state->aud_input > CX18_AV_AUDIO_SERIAL2) {
57 		switch (freq) {
58 		case 32000:
59 			/*
60 			 * VID_PLL Integer = 0x0f, VID_PLL Post Divider = 0x04
61 			 * AUX_PLL Integer = 0x0d, AUX PLL Post Divider = 0x20
62 			 */
63 			cx18_av_write4(cx, 0x108, 0x200d040f);
64 
65 			/* VID_PLL Fraction = 0x2be2fe */
66 			/* xtal * 0xf.15f17f0/4 = 108 MHz: 432 MHz pre-postdiv*/
67 			cx18_av_write4(cx, 0x10c, 0x002be2fe);
68 
69 			/* AUX_PLL Fraction = 0x176740c */
70 			/* xtal * 0xd.bb3a060/0x20 = 32000 * 384: 393 MHz p-pd*/
71 			cx18_av_write4(cx, 0x110, 0x0176740c);
72 
73 			/* src3/4/6_ctl */
74 			/* 0x1.f77f = (4 * xtal/8*2/455) / 32000 */
75 			cx18_av_write4(cx, 0x900, 0x0801f77f);
76 			cx18_av_write4(cx, 0x904, 0x0801f77f);
77 			cx18_av_write4(cx, 0x90c, 0x0801f77f);
78 
79 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x20 */
80 			cx18_av_write(cx, 0x127, 0x60);
81 
82 			/* AUD_COUNT = 0x2fff = 8 samples * 4 * 384 - 1 */
83 			cx18_av_write4(cx, 0x12c, 0x11202fff);
84 
85 			/*
86 			 * EN_AV_LOCK = 0
87 			 * VID_COUNT = 0x0d2ef8 = 107999.000 * 8 =
88 			 *  ((8 samples/32,000) * (13,500,000 * 8) * 4 - 1) * 8
89 			 */
90 			cx18_av_write4(cx, 0x128, 0xa00d2ef8);
91 			break;
92 
93 		case 44100:
94 			/*
95 			 * VID_PLL Integer = 0x0f, VID_PLL Post Divider = 0x04
96 			 * AUX_PLL Integer = 0x0e, AUX PLL Post Divider = 0x18
97 			 */
98 			cx18_av_write4(cx, 0x108, 0x180e040f);
99 
100 			/* VID_PLL Fraction = 0x2be2fe */
101 			/* xtal * 0xf.15f17f0/4 = 108 MHz: 432 MHz pre-postdiv*/
102 			cx18_av_write4(cx, 0x10c, 0x002be2fe);
103 
104 			/* AUX_PLL Fraction = 0x062a1f2 */
105 			/* xtal * 0xe.3150f90/0x18 = 44100 * 384: 406 MHz p-pd*/
106 			cx18_av_write4(cx, 0x110, 0x0062a1f2);
107 
108 			/* src3/4/6_ctl */
109 			/* 0x1.6d59 = (4 * xtal/8*2/455) / 44100 */
110 			cx18_av_write4(cx, 0x900, 0x08016d59);
111 			cx18_av_write4(cx, 0x904, 0x08016d59);
112 			cx18_av_write4(cx, 0x90c, 0x08016d59);
113 
114 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x18 */
115 			cx18_av_write(cx, 0x127, 0x58);
116 
117 			/* AUD_COUNT = 0x92ff = 49 samples * 2 * 384 - 1 */
118 			cx18_av_write4(cx, 0x12c, 0x112092ff);
119 
120 			/*
121 			 * EN_AV_LOCK = 0
122 			 * VID_COUNT = 0x1d4bf8 = 239999.000 * 8 =
123 			 *  ((49 samples/44,100) * (13,500,000 * 8) * 2 - 1) * 8
124 			 */
125 			cx18_av_write4(cx, 0x128, 0xa01d4bf8);
126 			break;
127 
128 		case 48000:
129 			/*
130 			 * VID_PLL Integer = 0x0f, VID_PLL Post Divider = 0x04
131 			 * AUX_PLL Integer = 0x0e, AUX PLL Post Divider = 0x16
132 			 */
133 			cx18_av_write4(cx, 0x108, 0x160e040f);
134 
135 			/* VID_PLL Fraction = 0x2be2fe */
136 			/* xtal * 0xf.15f17f0/4 = 108 MHz: 432 MHz pre-postdiv*/
137 			cx18_av_write4(cx, 0x10c, 0x002be2fe);
138 
139 			/* AUX_PLL Fraction = 0x05227ad */
140 			/* xtal * 0xe.2913d68/0x16 = 48000 * 384: 406 MHz p-pd*/
141 			cx18_av_write4(cx, 0x110, 0x005227ad);
142 
143 			/* src3/4/6_ctl */
144 			/* 0x1.4faa = (4 * xtal/8*2/455) / 48000 */
145 			cx18_av_write4(cx, 0x900, 0x08014faa);
146 			cx18_av_write4(cx, 0x904, 0x08014faa);
147 			cx18_av_write4(cx, 0x90c, 0x08014faa);
148 
149 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x16 */
150 			cx18_av_write(cx, 0x127, 0x56);
151 
152 			/* AUD_COUNT = 0x5fff = 4 samples * 16 * 384 - 1 */
153 			cx18_av_write4(cx, 0x12c, 0x11205fff);
154 
155 			/*
156 			 * EN_AV_LOCK = 0
157 			 * VID_COUNT = 0x1193f8 = 143999.000 * 8 =
158 			 *  ((4 samples/48,000) * (13,500,000 * 8) * 16 - 1) * 8
159 			 */
160 			cx18_av_write4(cx, 0x128, 0xa01193f8);
161 			break;
162 		}
163 	} else {
164 		switch (freq) {
165 		case 32000:
166 			/*
167 			 * VID_PLL Integer = 0x0f, VID_PLL Post Divider = 0x04
168 			 * AUX_PLL Integer = 0x0d, AUX PLL Post Divider = 0x30
169 			 */
170 			cx18_av_write4(cx, 0x108, 0x300d040f);
171 
172 			/* VID_PLL Fraction = 0x2be2fe */
173 			/* xtal * 0xf.15f17f0/4 = 108 MHz: 432 MHz pre-postdiv*/
174 			cx18_av_write4(cx, 0x10c, 0x002be2fe);
175 
176 			/* AUX_PLL Fraction = 0x176740c */
177 			/* xtal * 0xd.bb3a060/0x30 = 32000 * 256: 393 MHz p-pd*/
178 			cx18_av_write4(cx, 0x110, 0x0176740c);
179 
180 			/* src1_ctl */
181 			/* 0x1.0000 = 32000/32000 */
182 			cx18_av_write4(cx, 0x8f8, 0x08010000);
183 
184 			/* src3/4/6_ctl */
185 			/* 0x2.0000 = 2 * (32000/32000) */
186 			cx18_av_write4(cx, 0x900, 0x08020000);
187 			cx18_av_write4(cx, 0x904, 0x08020000);
188 			cx18_av_write4(cx, 0x90c, 0x08020000);
189 
190 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x30 */
191 			cx18_av_write(cx, 0x127, 0x70);
192 
193 			/* AUD_COUNT = 0x1fff = 8 samples * 4 * 256 - 1 */
194 			cx18_av_write4(cx, 0x12c, 0x11201fff);
195 
196 			/*
197 			 * EN_AV_LOCK = 0
198 			 * VID_COUNT = 0x0d2ef8 = 107999.000 * 8 =
199 			 *  ((8 samples/32,000) * (13,500,000 * 8) * 4 - 1) * 8
200 			 */
201 			cx18_av_write4(cx, 0x128, 0xa00d2ef8);
202 			break;
203 
204 		case 44100:
205 			/*
206 			 * VID_PLL Integer = 0x0f, VID_PLL Post Divider = 0x04
207 			 * AUX_PLL Integer = 0x0e, AUX PLL Post Divider = 0x24
208 			 */
209 			cx18_av_write4(cx, 0x108, 0x240e040f);
210 
211 			/* VID_PLL Fraction = 0x2be2fe */
212 			/* xtal * 0xf.15f17f0/4 = 108 MHz: 432 MHz pre-postdiv*/
213 			cx18_av_write4(cx, 0x10c, 0x002be2fe);
214 
215 			/* AUX_PLL Fraction = 0x062a1f2 */
216 			/* xtal * 0xe.3150f90/0x24 = 44100 * 256: 406 MHz p-pd*/
217 			cx18_av_write4(cx, 0x110, 0x0062a1f2);
218 
219 			/* src1_ctl */
220 			/* 0x1.60cd = 44100/32000 */
221 			cx18_av_write4(cx, 0x8f8, 0x080160cd);
222 
223 			/* src3/4/6_ctl */
224 			/* 0x1.7385 = 2 * (32000/44100) */
225 			cx18_av_write4(cx, 0x900, 0x08017385);
226 			cx18_av_write4(cx, 0x904, 0x08017385);
227 			cx18_av_write4(cx, 0x90c, 0x08017385);
228 
229 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x24 */
230 			cx18_av_write(cx, 0x127, 0x64);
231 
232 			/* AUD_COUNT = 0x61ff = 49 samples * 2 * 256 - 1 */
233 			cx18_av_write4(cx, 0x12c, 0x112061ff);
234 
235 			/*
236 			 * EN_AV_LOCK = 0
237 			 * VID_COUNT = 0x1d4bf8 = 239999.000 * 8 =
238 			 *  ((49 samples/44,100) * (13,500,000 * 8) * 2 - 1) * 8
239 			 */
240 			cx18_av_write4(cx, 0x128, 0xa01d4bf8);
241 			break;
242 
243 		case 48000:
244 			/*
245 			 * VID_PLL Integer = 0x0f, VID_PLL Post Divider = 0x04
246 			 * AUX_PLL Integer = 0x0d, AUX PLL Post Divider = 0x20
247 			 */
248 			cx18_av_write4(cx, 0x108, 0x200d040f);
249 
250 			/* VID_PLL Fraction = 0x2be2fe */
251 			/* xtal * 0xf.15f17f0/4 = 108 MHz: 432 MHz pre-postdiv*/
252 			cx18_av_write4(cx, 0x10c, 0x002be2fe);
253 
254 			/* AUX_PLL Fraction = 0x176740c */
255 			/* xtal * 0xd.bb3a060/0x20 = 48000 * 256: 393 MHz p-pd*/
256 			cx18_av_write4(cx, 0x110, 0x0176740c);
257 
258 			/* src1_ctl */
259 			/* 0x1.8000 = 48000/32000 */
260 			cx18_av_write4(cx, 0x8f8, 0x08018000);
261 
262 			/* src3/4/6_ctl */
263 			/* 0x1.5555 = 2 * (32000/48000) */
264 			cx18_av_write4(cx, 0x900, 0x08015555);
265 			cx18_av_write4(cx, 0x904, 0x08015555);
266 			cx18_av_write4(cx, 0x90c, 0x08015555);
267 
268 			/* SA_MCLK_SEL=1, SA_MCLK_DIV=0x20 */
269 			cx18_av_write(cx, 0x127, 0x60);
270 
271 			/* AUD_COUNT = 0x3fff = 4 samples * 16 * 256 - 1 */
272 			cx18_av_write4(cx, 0x12c, 0x11203fff);
273 
274 			/*
275 			 * EN_AV_LOCK = 0
276 			 * VID_COUNT = 0x1193f8 = 143999.000 * 8 =
277 			 *  ((4 samples/48,000) * (13,500,000 * 8) * 16 - 1) * 8
278 			 */
279 			cx18_av_write4(cx, 0x128, 0xa01193f8);
280 			break;
281 		}
282 	}
283 
284 	state->audclk_freq = freq;
285 
286 	return 0;
287 }
288 
cx18_av_audio_set_path(struct cx18 * cx)289 void cx18_av_audio_set_path(struct cx18 *cx)
290 {
291 	struct cx18_av_state *state = &cx->av_state;
292 	u8 v;
293 
294 	/* stop microcontroller */
295 	v = cx18_av_read(cx, 0x803) & ~0x10;
296 	cx18_av_write_expect(cx, 0x803, v, v, 0x1f);
297 
298 	/* assert soft reset */
299 	v = cx18_av_read(cx, 0x810) | 0x01;
300 	cx18_av_write_expect(cx, 0x810, v, v, 0x0f);
301 
302 	/* Mute everything to prevent the PFFT! */
303 	cx18_av_write(cx, 0x8d3, 0x1f);
304 
305 	if (state->aud_input <= CX18_AV_AUDIO_SERIAL2) {
306 		/* Set Path1 to Serial Audio Input */
307 		cx18_av_write4(cx, 0x8d0, 0x01011012);
308 
309 		/* The microcontroller should not be started for the
310 		 * non-tuner inputs: autodetection is specific for
311 		 * TV audio. */
312 	} else {
313 		/* Set Path1 to Analog Demod Main Channel */
314 		cx18_av_write4(cx, 0x8d0, 0x1f063870);
315 	}
316 
317 	set_audclk_freq(cx, state->audclk_freq);
318 
319 	/* deassert soft reset */
320 	v = cx18_av_read(cx, 0x810) & ~0x01;
321 	cx18_av_write_expect(cx, 0x810, v, v, 0x0f);
322 
323 	if (state->aud_input > CX18_AV_AUDIO_SERIAL2) {
324 		/* When the microcontroller detects the
325 		 * audio format, it will unmute the lines */
326 		v = cx18_av_read(cx, 0x803) | 0x10;
327 		cx18_av_write_expect(cx, 0x803, v, v, 0x1f);
328 	}
329 }
330 
set_volume(struct cx18 * cx,int volume)331 static void set_volume(struct cx18 *cx, int volume)
332 {
333 	/* First convert the volume to msp3400 values (0-127) */
334 	int vol = volume >> 9;
335 	/* now scale it up to cx18_av values
336 	 * -114dB to -96dB maps to 0
337 	 * this should be 19, but in my testing that was 4dB too loud */
338 	if (vol <= 23)
339 		vol = 0;
340 	else
341 		vol -= 23;
342 
343 	/* PATH1_VOLUME */
344 	cx18_av_write(cx, 0x8d4, 228 - (vol * 2));
345 }
346 
set_bass(struct cx18 * cx,int bass)347 static void set_bass(struct cx18 *cx, int bass)
348 {
349 	/* PATH1_EQ_BASS_VOL */
350 	cx18_av_and_or(cx, 0x8d9, ~0x3f, 48 - (bass * 48 / 0xffff));
351 }
352 
set_treble(struct cx18 * cx,int treble)353 static void set_treble(struct cx18 *cx, int treble)
354 {
355 	/* PATH1_EQ_TREBLE_VOL */
356 	cx18_av_and_or(cx, 0x8db, ~0x3f, 48 - (treble * 48 / 0xffff));
357 }
358 
set_balance(struct cx18 * cx,int balance)359 static void set_balance(struct cx18 *cx, int balance)
360 {
361 	int bal = balance >> 8;
362 	if (bal > 0x80) {
363 		/* PATH1_BAL_LEFT */
364 		cx18_av_and_or(cx, 0x8d5, 0x7f, 0x80);
365 		/* PATH1_BAL_LEVEL */
366 		cx18_av_and_or(cx, 0x8d5, ~0x7f, bal & 0x7f);
367 	} else {
368 		/* PATH1_BAL_LEFT */
369 		cx18_av_and_or(cx, 0x8d5, 0x7f, 0x00);
370 		/* PATH1_BAL_LEVEL */
371 		cx18_av_and_or(cx, 0x8d5, ~0x7f, 0x80 - bal);
372 	}
373 }
374 
set_mute(struct cx18 * cx,int mute)375 static void set_mute(struct cx18 *cx, int mute)
376 {
377 	struct cx18_av_state *state = &cx->av_state;
378 	u8 v;
379 
380 	if (state->aud_input > CX18_AV_AUDIO_SERIAL2) {
381 		/* Must turn off microcontroller in order to mute sound.
382 		 * Not sure if this is the best method, but it does work.
383 		 * If the microcontroller is running, then it will undo any
384 		 * changes to the mute register. */
385 		v = cx18_av_read(cx, 0x803);
386 		if (mute) {
387 			/* disable microcontroller */
388 			v &= ~0x10;
389 			cx18_av_write_expect(cx, 0x803, v, v, 0x1f);
390 			cx18_av_write(cx, 0x8d3, 0x1f);
391 		} else {
392 			/* enable microcontroller */
393 			v |= 0x10;
394 			cx18_av_write_expect(cx, 0x803, v, v, 0x1f);
395 		}
396 	} else {
397 		/* SRC1_MUTE_EN */
398 		cx18_av_and_or(cx, 0x8d3, ~0x2, mute ? 0x02 : 0x00);
399 	}
400 }
401 
cx18_av_s_clock_freq(struct v4l2_subdev * sd,u32 freq)402 int cx18_av_s_clock_freq(struct v4l2_subdev *sd, u32 freq)
403 {
404 	struct cx18 *cx = v4l2_get_subdevdata(sd);
405 	struct cx18_av_state *state = &cx->av_state;
406 	int retval;
407 	u8 v;
408 
409 	if (state->aud_input > CX18_AV_AUDIO_SERIAL2) {
410 		v = cx18_av_read(cx, 0x803) & ~0x10;
411 		cx18_av_write_expect(cx, 0x803, v, v, 0x1f);
412 		cx18_av_write(cx, 0x8d3, 0x1f);
413 	}
414 	v = cx18_av_read(cx, 0x810) | 0x1;
415 	cx18_av_write_expect(cx, 0x810, v, v, 0x0f);
416 
417 	retval = set_audclk_freq(cx, freq);
418 
419 	v = cx18_av_read(cx, 0x810) & ~0x1;
420 	cx18_av_write_expect(cx, 0x810, v, v, 0x0f);
421 	if (state->aud_input > CX18_AV_AUDIO_SERIAL2) {
422 		v = cx18_av_read(cx, 0x803) | 0x10;
423 		cx18_av_write_expect(cx, 0x803, v, v, 0x1f);
424 	}
425 	return retval;
426 }
427 
cx18_av_audio_s_ctrl(struct v4l2_ctrl * ctrl)428 static int cx18_av_audio_s_ctrl(struct v4l2_ctrl *ctrl)
429 {
430 	struct v4l2_subdev *sd = to_sd(ctrl);
431 	struct cx18 *cx = v4l2_get_subdevdata(sd);
432 
433 	switch (ctrl->id) {
434 	case V4L2_CID_AUDIO_VOLUME:
435 		set_volume(cx, ctrl->val);
436 		break;
437 	case V4L2_CID_AUDIO_BASS:
438 		set_bass(cx, ctrl->val);
439 		break;
440 	case V4L2_CID_AUDIO_TREBLE:
441 		set_treble(cx, ctrl->val);
442 		break;
443 	case V4L2_CID_AUDIO_BALANCE:
444 		set_balance(cx, ctrl->val);
445 		break;
446 	case V4L2_CID_AUDIO_MUTE:
447 		set_mute(cx, ctrl->val);
448 		break;
449 	default:
450 		return -EINVAL;
451 	}
452 	return 0;
453 }
454 
455 const struct v4l2_ctrl_ops cx18_av_audio_ctrl_ops = {
456 	.s_ctrl = cx18_av_audio_s_ctrl,
457 };
458