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cx18-alsa-mixer.c
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1 /*
2  * ALSA mixer controls for the
3  * ALSA interface to cx18 PCM capture streams
4  *
5  * Copyright (C) 2009 Andy Walls <[email protected]>
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 "cx18-alsa.h"
36 #include "cx18-driver.h"
37 
38 /*
39  * Note the cx18-av-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  */
54 static inline int dB_to_cx18_av_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 
63 static inline int cx18_av_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 
72 static int snd_cx18_mixer_tv_vol_info(struct snd_kcontrol *kcontrol,
73  struct snd_ctl_elem_info *uinfo)
74 {
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 
84 static int snd_cx18_mixer_tv_vol_get(struct snd_kcontrol *kctl,
85  struct snd_ctl_elem_value *uctl)
86 {
87  struct snd_cx18_card *cxsc = snd_kcontrol_chip(kctl);
88  struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
89  struct v4l2_control vctrl;
90  int ret;
91 
92  vctrl.id = V4L2_CID_AUDIO_VOLUME;
93  vctrl.value = dB_to_cx18_av_vol(uctl->value.integer.value[0]);
94 
95  snd_cx18_lock(cxsc);
96  ret = v4l2_subdev_call(cx->sd_av, core, g_ctrl, &vctrl);
97  snd_cx18_unlock(cxsc);
98 
99  if (!ret)
100  uctl->value.integer.value[0] = cx18_av_vol_to_dB(vctrl.value);
101  return ret;
102 }
103 
104 static int snd_cx18_mixer_tv_vol_put(struct snd_kcontrol *kctl,
105  struct snd_ctl_elem_value *uctl)
106 {
107  struct snd_cx18_card *cxsc = snd_kcontrol_chip(kctl);
108  struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
109  struct v4l2_control vctrl;
110  int ret;
111 
112  vctrl.id = V4L2_CID_AUDIO_VOLUME;
113  vctrl.value = dB_to_cx18_av_vol(uctl->value.integer.value[0]);
114 
115  snd_cx18_lock(cxsc);
116 
117  /* Fetch current state */
118  ret = v4l2_subdev_call(cx->sd_av, core, g_ctrl, &vctrl);
119 
120  if (ret ||
121  (cx18_av_vol_to_dB(vctrl.value) != uctl->value.integer.value[0])) {
122 
123  /* Set, if needed */
124  vctrl.value = dB_to_cx18_av_vol(uctl->value.integer.value[0]);
125  ret = v4l2_subdev_call(cx->sd_av, core, s_ctrl, &vctrl);
126  if (!ret)
127  ret = 1; /* Indicate control was changed w/o error */
128  }
129  snd_cx18_unlock(cxsc);
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_cx18_mixer_tv_vol_db_scale, -9600, 100, 0);
137 
138 static struct snd_kcontrol_new snd_cx18_mixer_tv_vol __initdata = {
140  .name = "Analog TV Capture Volume",
143  .info = snd_cx18_mixer_tv_volume_info,
144  .get = snd_cx18_mixer_tv_volume_get,
145  .put = snd_cx18_mixer_tv_volume_put,
146  .tlv.p = snd_cx18_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 CS5345 I2S volume for HVR-1600 */
160 
162 {
163  struct v4l2_device *v4l2_dev = cxsc->v4l2_dev;
164  struct snd_card *sc = cxsc->sc;
165  int ret;
166 
167  strlcpy(sc->mixername, "CX23418 Mixer", sizeof(sc->mixername));
168 
169  ret = snd_ctl_add(sc, snd_ctl_new1(snd_cx18_mixer_tv_vol, cxsc));
170  if (ret) {
171  CX18_ALSA_WARN("%s: failed to add %s control, err %d\n",
172  __func__, snd_cx18_mixer_tv_vol.name, ret);
173  }
174  return ret;
175 }