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1 /*
2  *  ALSA mixer controls for the
3  *  ALSA interface to ivtv PCM capture streams
4  *
5  *  Copyright (C) 2009,2012  Andy Walls <awalls@md.metrocast.net>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
20  *  02111-1307  USA
21  */
22 
23 #include <linux/init.h>
24 #include <linux/kernel.h>
25 #include <linux/device.h>
26 #include <linux/spinlock.h>
27 #include <linux/videodev2.h>
28 
29 #include <media/v4l2-device.h>
30 
31 #include <sound/core.h>
32 #include <sound/control.h>
33 #include <sound/tlv.h>
34 
35 #include "ivtv-alsa.h"
36 #include "ivtv-driver.h"
37 
38 /*
39  * Note the cx25840-core volume scale is funny, due to the alignment of the
40  * scale with another chip's range:
41  *
42  * v4l2_control value	/512	indicated dB	actual dB	reg 0x8d4
43  * 0x0000 - 0x01ff	  0	-119		-96		228
44  * 0x0200 - 0x02ff	  1	-118		-96		228
45  * ...
46  * 0x2c00 - 0x2dff	 22	 -97		-96		228
47  * 0x2e00 - 0x2fff	 23	 -96		-96		228
48  * 0x3000 - 0x31ff	 24	 -95		-95		226
49  * ...
50  * 0xee00 - 0xefff	119	   0		  0		 36
51  * ...
52  * 0xfe00 - 0xffff	127	  +8		 +8		 20
53  */
dB_to_cx25840_vol(int dB)54 static inline int dB_to_cx25840_vol(int dB)
55 {
56 	if (dB < -96)
57 		dB = -96;
58 	else if (dB > 8)
59 		dB = 8;
60 	return (dB + 119) << 9;
61 }
62 
cx25840_vol_to_dB(int v)63 static inline int cx25840_vol_to_dB(int v)
64 {
65 	if (v < (23 << 9))
66 		v = (23 << 9);
67 	else if (v > (127 << 9))
68 		v = (127 << 9);
69 	return (v >> 9) - 119;
70 }
71 
snd_ivtv_mixer_tv_vol_info(struct snd_kcontrol * kcontrol,struct snd_ctl_elem_info * uinfo)72 static int snd_ivtv_mixer_tv_vol_info(struct snd_kcontrol *kcontrol,
73 				      struct snd_ctl_elem_info *uinfo)
74 {
75 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
76 	uinfo->count = 1;
77 	/* We're already translating values, just keep this control in dB */
78 	uinfo->value.integer.min  = -96;
79 	uinfo->value.integer.max  =   8;
80 	uinfo->value.integer.step =   1;
81 	return 0;
82 }
83 
snd_ivtv_mixer_tv_vol_get(struct snd_kcontrol * kctl,struct snd_ctl_elem_value * uctl)84 static int snd_ivtv_mixer_tv_vol_get(struct snd_kcontrol *kctl,
85 				     struct snd_ctl_elem_value *uctl)
86 {
87 	struct snd_ivtv_card *itvsc = snd_kcontrol_chip(kctl);
88 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
89 	struct v4l2_control vctrl;
90 	int ret;
91 
92 	vctrl.id = V4L2_CID_AUDIO_VOLUME;
93 	vctrl.value = dB_to_cx25840_vol(uctl->value.integer.value[0]);
94 
95 	snd_ivtv_lock(itvsc);
96 	ret = v4l2_g_ctrl(itv->sd_audio->ctrl_handler, &vctrl);
97 	snd_ivtv_unlock(itvsc);
98 
99 	if (!ret)
100 		uctl->value.integer.value[0] = cx25840_vol_to_dB(vctrl.value);
101 	return ret;
102 }
103 
snd_ivtv_mixer_tv_vol_put(struct snd_kcontrol * kctl,struct snd_ctl_elem_value * uctl)104 static int snd_ivtv_mixer_tv_vol_put(struct snd_kcontrol *kctl,
105 				     struct snd_ctl_elem_value *uctl)
106 {
107 	struct snd_ivtv_card *itvsc = snd_kcontrol_chip(kctl);
108 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
109 	struct v4l2_control vctrl;
110 	int ret;
111 
112 	vctrl.id = V4L2_CID_AUDIO_VOLUME;
113 	vctrl.value = dB_to_cx25840_vol(uctl->value.integer.value[0]);
114 
115 	snd_ivtv_lock(itvsc);
116 
117 	/* Fetch current state */
118 	ret = v4l2_g_ctrl(itv->sd_audio->ctrl_handler, &vctrl);
119 
120 	if (ret ||
121 	    (cx25840_vol_to_dB(vctrl.value) != uctl->value.integer.value[0])) {
122 
123 		/* Set, if needed */
124 		vctrl.value = dB_to_cx25840_vol(uctl->value.integer.value[0]);
125 		ret = v4l2_s_ctrl(itv->sd_audio->ctrl_handler, &vctrl);
126 		if (!ret)
127 			ret = 1; /* Indicate control was changed w/o error */
128 	}
129 	snd_ivtv_unlock(itvsc);
130 
131 	return ret;
132 }
133 
134 
135 /* This is a bit of overkill, the slider is already in dB internally */
136 static DECLARE_TLV_DB_SCALE(snd_ivtv_mixer_tv_vol_db_scale, -9600, 100, 0);
137 
138 static struct snd_kcontrol_new snd_ivtv_mixer_tv_vol __initdata = {
139 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
140 	.name = "Analog TV Capture Volume",
141 	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
142 		  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
143 	.info = snd_ivtv_mixer_tv_volume_info,
144 	.get = snd_ivtv_mixer_tv_volume_get,
145 	.put = snd_ivtv_mixer_tv_volume_put,
146 	.tlv.p = snd_ivtv_mixer_tv_vol_db_scale
147 };
148 
149 /* FIXME - add mute switch and balance, bass, treble sliders:
150 	V4L2_CID_AUDIO_MUTE
151 
152 	V4L2_CID_AUDIO_BALANCE
153 
154 	V4L2_CID_AUDIO_BASS
155 	V4L2_CID_AUDIO_TREBLE
156 */
157 
158 /* FIXME - add stereo, lang1, lang2, mono menu */
159 /* FIXME - add I2S volume */
160 
snd_ivtv_mixer_create(struct snd_ivtv_card * itvsc)161 int __init snd_ivtv_mixer_create(struct snd_ivtv_card *itvsc)
162 {
163 	struct v4l2_device *v4l2_dev = itvsc->v4l2_dev;
164 	struct snd_card *sc = itvsc->sc;
165 	int ret;
166 
167 	strlcpy(sc->mixername, "CX2341[56] Mixer", sizeof(sc->mixername));
168 
169 	ret = snd_ctl_add(sc, snd_ctl_new1(snd_ivtv_mixer_tv_vol, itvsc));
170 	if (ret) {
171 		IVTV_ALSA_WARN("%s: failed to add %s control, err %d\n",
172 			       __func__, snd_ivtv_mixer_tv_vol.name, ret);
173 	}
174 	return ret;
175 }
176