drivers/media/pci/cx18/cx18-alsa-mixer.c

   1 /*
   2  *  ALSA mixer controls for the
   3  *  ALSA interface to cx18 PCM capture streams
   4  *
   5  *  Copyright (C) 2009  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
  18 #include <linux/init.h>
  19 #include <linux/kernel.h>
  20 #include <linux/device.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/videodev2.h>
  23
  24 #include <media/v4l2-device.h>
  25
  26 #include <sound/core.h>
  27 #include <sound/control.h>
  28 #include <sound/tlv.h>
  29
  30 #include "cx18-alsa.h"
  31 #include "cx18-driver.h"
  32
  33 /*
  34  * Note the cx18-av-core volume scale is funny, due to the alignment of the
  35  * scale with another chip's range:
  36  *
  37  * v4l2_control value   /512    indicated dB    actual dB       reg 0x8d4
  38  * 0x0000 - 0x01ff        0     -119            -96             228
  39  * 0x0200 - 0x02ff        1     -118            -96             228
  40  * ...
  41  * 0x2c00 - 0x2dff       22      -97            -96             228
  42  * 0x2e00 - 0x2fff       23      -96            -96             228
  43  * 0x3000 - 0x31ff       24      -95            -95             226
  44  * ...
  45  * 0xee00 - 0xefff      119        0              0              36
  46  * ...
  47  * 0xfe00 - 0xffff      127       +8             +8              20
  48  */
  49 static inline int dB_to_cx18_av_vol(int dB)
  50 {
  51         if (dB < -96)
  52                 dB = -96;
  53         else if (dB > 8)
  54                 dB = 8;
  55         return (dB + 119) << 9;
  56 }
  57
  58 static inline int cx18_av_vol_to_dB(int v)
  59 {
  60         if (v < (23 << 9))
  61                 v = (23 << 9);
  62         else if (v > (127 << 9))
  63                 v = (127 << 9);
  64         return (v >> 9) - 119;
  65 }
  66
  67 static int snd_cx18_mixer_tv_vol_info(struct snd_kcontrol *kcontrol,
  68                                       struct snd_ctl_elem_info *uinfo)
  69 {
  70         uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
  71         uinfo->count = 1;
  72         /* We're already translating values, just keep this control in dB */
  73         uinfo->value.integer.min  = -96;
  74         uinfo->value.integer.max  =   8;
  75         uinfo->value.integer.step =   1;
  76         return 0;
  77 }
  78
  79 static int snd_cx18_mixer_tv_vol_get(struct snd_kcontrol *kctl,
  80                                      struct snd_ctl_elem_value *uctl)
  81 {
  82         struct snd_cx18_card *cxsc = snd_kcontrol_chip(kctl);
  83         struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
  84         struct v4l2_control vctrl;
  85         int ret;
  86
  87         vctrl.id = V4L2_CID_AUDIO_VOLUME;
  88         vctrl.value = dB_to_cx18_av_vol(uctl->value.integer.value[0]);
  89
  90         snd_cx18_lock(cxsc);
  91         ret = v4l2_g_ctrl(cx->sd_av->ctrl_handler, &vctrl);
  92         snd_cx18_unlock(cxsc);
  93
  94         if (!ret)
  95                 uctl->value.integer.value[0] = cx18_av_vol_to_dB(vctrl.value);
  96         return ret;
  97 }
  98
  99 static int snd_cx18_mixer_tv_vol_put(struct snd_kcontrol *kctl,
 100                                      struct snd_ctl_elem_value *uctl)
 101 {
 102         struct snd_cx18_card *cxsc = snd_kcontrol_chip(kctl);
 103         struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
 104         struct v4l2_control vctrl;
 105         int ret;
 106
 107         vctrl.id = V4L2_CID_AUDIO_VOLUME;
 108         vctrl.value = dB_to_cx18_av_vol(uctl->value.integer.value[0]);
 109
 110         snd_cx18_lock(cxsc);
 111
 112         /* Fetch current state */
 113         ret = v4l2_g_ctrl(cx->sd_av->ctrl_handler, &vctrl);
 114
 115         if (ret ||
 116             (cx18_av_vol_to_dB(vctrl.value) != uctl->value.integer.value[0])) {
 117
 118                 /* Set, if needed */
 119                 vctrl.value = dB_to_cx18_av_vol(uctl->value.integer.value[0]);
 120                 ret = v4l2_s_ctrl(cx->sd_av->ctrl_handler, &vctrl);
 121                 if (!ret)
 122                         ret = 1; /* Indicate control was changed w/o error */
 123         }
 124         snd_cx18_unlock(cxsc);
 125
 126         return ret;
 127 }
 128
 129
 130 /* This is a bit of overkill, the slider is already in dB internally */
 131 static DECLARE_TLV_DB_SCALE(snd_cx18_mixer_tv_vol_db_scale, -9600, 100, 0);
 132
 133 static struct snd_kcontrol_new snd_cx18_mixer_tv_vol __initdata = {
 134         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
 135         .name = "Analog TV Capture Volume",
 136         .access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
 137                   SNDRV_CTL_ELEM_ACCESS_TLV_READ,
 138         .info = snd_cx18_mixer_tv_volume_info,
 139         .get = snd_cx18_mixer_tv_volume_get,
 140         .put = snd_cx18_mixer_tv_volume_put,
 141         .tlv.p = snd_cx18_mixer_tv_vol_db_scale
 142 };
 143
 144 /* FIXME - add mute switch and balance, bass, treble sliders:
 145         V4L2_CID_AUDIO_MUTE
 146
 147         V4L2_CID_AUDIO_BALANCE
 148
 149         V4L2_CID_AUDIO_BASS
 150         V4L2_CID_AUDIO_TREBLE
 151 */
 152
 153 /* FIXME - add stereo, lang1, lang2, mono menu */
 154 /* FIXME - add CS5345 I2S volume for HVR-1600 */
 155
 156 int __init snd_cx18_mixer_create(struct snd_cx18_card *cxsc)
 157 {
 158         struct v4l2_device *v4l2_dev = cxsc->v4l2_dev;
 159         struct snd_card *sc = cxsc->sc;
 160         int ret;
 161
 162         strlcpy(sc->mixername, "CX23418 Mixer", sizeof(sc->mixername));
 163
 164         ret = snd_ctl_add(sc, snd_ctl_new1(&snd_cx18_mixer_tv_vol, cxsc));
 165         if (ret) {
 166                 CX18_ALSA_WARN("%s: failed to add %s control, err %d\n",
 167                                 __func__, snd_cx18_mixer_tv_vol.name, ret);
 168         }
 169         return ret;
 170 }