xref: /linux/drivers/media/pci/cx18/cx18-audio.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  *  cx18 audio-related functions
3  *
4  *  Derived from ivtv-audio.c
5  *
6  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  */
18 
19 #include "cx18-driver.h"
20 #include "cx18-io.h"
21 #include "cx18-cards.h"
22 #include "cx18-audio.h"
23 
24 #define CX18_AUDIO_ENABLE    0xc72014
25 #define CX18_AI1_MUX_MASK    0x30
26 #define CX18_AI1_MUX_I2S1    0x00
27 #define CX18_AI1_MUX_I2S2    0x10
28 #define CX18_AI1_MUX_843_I2S 0x20
29 
30 /* Selects the audio input and output according to the current
31    settings. */
32 int cx18_audio_set_io(struct cx18 *cx)
33 {
34 	const struct cx18_card_audio_input *in;
35 	u32 u, v;
36 	int err;
37 
38 	/* Determine which input to use */
39 	if (test_bit(CX18_F_I_RADIO_USER, &cx->i_flags))
40 		in = &cx->card->radio_input;
41 	else
42 		in = &cx->card->audio_inputs[cx->audio_input];
43 
44 	/* handle muxer chips */
45 	v4l2_subdev_call(cx->sd_extmux, audio, s_routing,
46 			 (u32) in->muxer_input, 0, 0);
47 
48 	err = cx18_call_hw_err(cx, cx->card->hw_audio_ctrl,
49 			       audio, s_routing, in->audio_input, 0, 0);
50 	if (err)
51 		return err;
52 
53 	/* FIXME - this internal mux should be abstracted to a subdev */
54 	u = cx18_read_reg(cx, CX18_AUDIO_ENABLE);
55 	v = u & ~CX18_AI1_MUX_MASK;
56 	switch (in->audio_input) {
57 	case CX18_AV_AUDIO_SERIAL1:
58 		v |= CX18_AI1_MUX_I2S1;
59 		break;
60 	case CX18_AV_AUDIO_SERIAL2:
61 		v |= CX18_AI1_MUX_I2S2;
62 		break;
63 	default:
64 		v |= CX18_AI1_MUX_843_I2S;
65 		break;
66 	}
67 	if (v == u) {
68 		/* force a toggle of some AI1 MUX control bits */
69 		u &= ~CX18_AI1_MUX_MASK;
70 		switch (in->audio_input) {
71 		case CX18_AV_AUDIO_SERIAL1:
72 			u |= CX18_AI1_MUX_843_I2S;
73 			break;
74 		case CX18_AV_AUDIO_SERIAL2:
75 			u |= CX18_AI1_MUX_843_I2S;
76 			break;
77 		default:
78 			u |= CX18_AI1_MUX_I2S1;
79 			break;
80 		}
81 		cx18_write_reg_expect(cx, u | 0xb00, CX18_AUDIO_ENABLE,
82 				      u, CX18_AI1_MUX_MASK);
83 	}
84 	cx18_write_reg_expect(cx, v | 0xb00, CX18_AUDIO_ENABLE,
85 			      v, CX18_AI1_MUX_MASK);
86 	return 0;
87 }
88