From 79d396583b856fc5bfa3470e0093e2cf204ef24c Mon Sep 17 00:00:00 2001 From: Simon Wilson Date: Wed, 25 May 2011 13:44:23 -0700 Subject: Initial contribution --- mixer.c | 332 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 332 insertions(+) create mode 100644 mixer.c (limited to 'mixer.c') diff --git a/mixer.c b/mixer.c new file mode 100644 index 0000000..9c7e3b5 --- /dev/null +++ b/mixer.c @@ -0,0 +1,332 @@ +/* mixer.c +** +** Copyright 2011, The Android Open Source Project +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions are met: +** * Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** * Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in the +** documentation and/or other materials provided with the distribution. +** * Neither the name of The Android Open Source Project nor the names of +** its contributors may be used to endorse or promote products derived +** from this software without specific prior written permission. +** +** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND +** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE +** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH +** DAMAGE. +*/ + +#include +#include +#include +#include +#include +#include +#include + +#include +#define __force +#define __bitwise +#define __user +#include + +#include + +static const char *elem_iface_name(snd_ctl_elem_iface_t n) +{ + switch (n) { + case SNDRV_CTL_ELEM_IFACE_CARD: return "CARD"; + case SNDRV_CTL_ELEM_IFACE_HWDEP: return "HWDEP"; + case SNDRV_CTL_ELEM_IFACE_MIXER: return "MIXER"; + case SNDRV_CTL_ELEM_IFACE_PCM: return "PCM"; + case SNDRV_CTL_ELEM_IFACE_RAWMIDI: return "MIDI"; + case SNDRV_CTL_ELEM_IFACE_TIMER: return "TIMER"; + case SNDRV_CTL_ELEM_IFACE_SEQUENCER: return "SEQ"; + default: return "???"; + } +} + +static const char *elem_type_name(snd_ctl_elem_type_t n) +{ + switch (n) { + case SNDRV_CTL_ELEM_TYPE_NONE: return "NONE"; + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return "BOOL"; + case SNDRV_CTL_ELEM_TYPE_INTEGER: return "INT32"; + case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return "ENUM"; + case SNDRV_CTL_ELEM_TYPE_BYTES: return "BYTES"; + case SNDRV_CTL_ELEM_TYPE_IEC958: return "IEC958"; + case SNDRV_CTL_ELEM_TYPE_INTEGER64: return "INT64"; + default: return "???"; + } +} + + +struct mixer_ctl { + struct mixer *mixer; + struct snd_ctl_elem_info *info; + char **ename; +}; + +struct mixer { + int fd; + struct snd_ctl_elem_info *info; + struct mixer_ctl *ctl; + unsigned int count; +}; + +void mixer_close(struct mixer *mixer) +{ + unsigned int n,m; + + if (mixer->fd >= 0) + close(mixer->fd); + + if (mixer->ctl) { + for (n = 0; n < mixer->count; n++) { + if (mixer->ctl[n].ename) { + unsigned int max = mixer->ctl[n].info->value.enumerated.items; + for (m = 0; m < max; m++) + free(mixer->ctl[n].ename[m]); + free(mixer->ctl[n].ename); + } + } + free(mixer->ctl); + } + + if (mixer->info) + free(mixer->info); + + free(mixer); + + /* TODO: verify frees */ +} + +struct mixer *mixer_open(unsigned int device) +{ + struct snd_ctl_elem_list elist; + struct snd_ctl_elem_info tmp; + struct snd_ctl_elem_id *eid = NULL; + struct mixer *mixer = NULL; + unsigned int n, m; + int fd; + + fd = open("/dev/snd/controlC0", O_RDWR); + if (fd < 0) + return 0; + + memset(&elist, 0, sizeof(elist)); + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0) + goto fail; + + mixer = calloc(1, sizeof(*mixer)); + if (!mixer) + goto fail; + + mixer->ctl = calloc(elist.count, sizeof(struct mixer_ctl)); + mixer->info = calloc(elist.count, sizeof(struct snd_ctl_elem_info)); + if (!mixer->ctl || !mixer->info) + goto fail; + + eid = calloc(elist.count, sizeof(struct snd_ctl_elem_id)); + if (!eid) + goto fail; + + mixer->count = elist.count; + mixer->fd = fd; + elist.space = mixer->count; + elist.pids = eid; + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0) + goto fail; + + for (n = 0; n < mixer->count; n++) { + struct snd_ctl_elem_info *ei = mixer->info + n; + ei->id.numid = eid[n].numid; + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, ei) < 0) + goto fail; + mixer->ctl[n].info = ei; + mixer->ctl[n].mixer = mixer; + if (ei->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) { + char **enames = calloc(ei->value.enumerated.items, sizeof(char*)); + if (!enames) + goto fail; + mixer->ctl[n].ename = enames; + for (m = 0; m < ei->value.enumerated.items; m++) { + memset(&tmp, 0, sizeof(tmp)); + tmp.id.numid = ei->id.numid; + tmp.value.enumerated.item = m; + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &tmp) < 0) + goto fail; + enames[m] = strdup(tmp.value.enumerated.name); + if (!enames[m]) + goto fail; + } + } + } + + free(eid); + return mixer; + +fail: + /* TODO: verify frees in failure case */ + if (eid) + free(eid); + if (mixer) + mixer_close(mixer); + else if (fd >= 0) + close(fd); + return 0; +} + +int mixer_get_num_ctls(struct mixer *mixer) +{ + return mixer->count; +} + +struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id) +{ + if (id < mixer->count) + return mixer->ctl + id; + + return NULL; +} + +struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name) +{ + unsigned int n; + for (n = 0; n < mixer->count; n++) + if (!strcmp(name, (char*) mixer->info[n].id.name)) + return mixer->ctl + n; + + return NULL; +} + +static int percent_to_int(struct snd_ctl_elem_info *ei, int percent) +{ + int range; + + if (percent > 100) + percent = 100; + else if (percent < 0) + percent = 0; + + range = (ei->value.integer.max - ei->value.integer.min); + + return ei->value.integer.min + (range * percent) / 100; +} + +static int int_to_percent(struct snd_ctl_elem_info *ei, int value) +{ + int range = (ei->value.integer.max - ei->value.integer.min); + + if (range == 0) + return 0; + + return ((value - ei->value.integer.min) / range) * 100; +} + +int mixer_ctl_get_percent(struct mixer_ctl *ctl) +{ + struct snd_ctl_elem_value ev; + + memset(&ev, 0, sizeof(ev)); + ev.id.numid = ctl->info->id.numid; + if (ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev)) + return -1; + + switch (ctl->info->type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: + return !!ev.value.integer.value[0]; /* TODO: handle multiple return values */ + break; + case SNDRV_CTL_ELEM_TYPE_INTEGER: { + return int_to_percent(ctl->info, ev.value.integer.value[0]); + break; + } + default: + errno = EINVAL; + return -1; + } + + return 0; +} + +int mixer_ctl_set_percent(struct mixer_ctl *ctl, int percent) +{ + struct snd_ctl_elem_value ev; + unsigned int n; + + memset(&ev, 0, sizeof(ev)); + ev.id.numid = ctl->info->id.numid; + switch (ctl->info->type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: + for (n = 0; n < ctl->info->count; n++) + ev.value.integer.value[n] = !!percent; /* TODO: handle multiple set values */ + break; + + case SNDRV_CTL_ELEM_TYPE_INTEGER: { + int value = percent_to_int(ctl->info, percent); + for (n = 0; n < ctl->info->count; n++) + ev.value.integer.value[n] = value; + break; + } + + default: + errno = EINVAL; + return -1; + } + + return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev); +} + +int mixer_ctl_set_enum(struct mixer_ctl *ctl, unsigned int id) +{ + struct snd_ctl_elem_value ev; + + if ((ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED) || + (id >= ctl->info->value.enumerated.items)) { + errno = EINVAL; + return -1; + } + + memset(&ev, 0, sizeof(ev)); + ev.value.enumerated.item[0] = id; + ev.id.numid = ctl->info->id.numid; + if (ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev) < 0) + return -1; + return 0; +} + +int mixer_ctl_set_enum_by_name(struct mixer_ctl *ctl, const char *string) +{ + unsigned int n, max; + struct snd_ctl_elem_value ev; + + if (ctl->info->type != SNDRV_CTL_ELEM_TYPE_ENUMERATED) { + errno = EINVAL; + return -1; + } + + max = ctl->info->value.enumerated.items; + for (n = 0; n < max; n++) { + if (!strcmp(string, ctl->ename[n])) { + memset(&ev, 0, sizeof(ev)); + ev.value.enumerated.item[0] = n; + ev.id.numid = ctl->info->id.numid; + if (ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev) < 0) + return -1; + return 0; + } + } + + errno = EINVAL; + return -1; +} -- cgit v1.2.3