Hi,
I have made a new attempt at adding support for dB gain reports in
alsamixer.
See the attached diffs against the current alsa hg repository. 27-5-2006
It shows an example of support for the snd-ca0106 driver.
As one can see, this adds minimal amounts of code to each sound card
driver. 22 new lines + 1 per volume control making 33 lines total.
Any comments?
James
diff -r 551da56a592c core/control.c
--- a/core/control.c Fri May 19 19:22:34 2006 +0200
+++ b/core/control.c Sat May 27 19:53:59 2006 +0100
@@ -241,6 +241,7 @@ struct snd_kcontrol *snd_ctl_new1(const
kctl.info = ncontrol->info;
kctl.get = ncontrol->get;
kctl.put = ncontrol->put;
+ kctl.info2 = ncontrol->info2;
kctl.private_value = ncontrol->private_value;
kctl.private_data = private_data;
return snd_ctl_new(&kctl, access);
@@ -570,6 +571,172 @@ static int snd_ctl_card_info(struct snd_
}
kfree(info);
return 0;
+}
+
+static int uint32_to_message(struct snd_ctl_misc *misc, u32 value)
+{
+ unsigned int pointer = misc->length;
+ u32 *store = (u32*) &misc->message[pointer];
+ *store = value;
+ misc->length += sizeof(u32);
+ return 0;
+}
+
+static int message_to_uint32(struct snd_ctl_misc *misc, unsigned int *value)
+{
+ unsigned int pointer = misc->length;
+ u32 *store = (u32*) &misc->message[pointer];
+ *value = *store;
+ misc->length += sizeof(u32);
+ return 0;
+}
+
+
+static int add_int32_tlv_to_container(struct snd_ctl_misc *misc, unsigned int type, unsigned int value)
+{
+ uint32_to_message(misc, type);
+ uint32_to_message(misc, 4);
+ uint32_to_message(misc, value);
+ /* FIXME: Check for overflows */
+ return 0;
+}
+
+static int add_message_tlv_to_container(
+ struct snd_ctl_misc *misc, unsigned int length, unsigned char *message)
+{
+ unsigned int pointer = misc->length;
+ unsigned int n;
+ for(n=0; n<length; n++) {
+ misc->message[pointer++] = message[n];
+ }
+ misc->length = pointer;
+ /* FIXME: Check for overflows */
+ return 0;
+}
+
+
+static int container_open(struct snd_ctl_misc *misc, unsigned int type)
+{
+ uint32_to_message(misc, type);
+ uint32_to_message(misc, 0); /* This gets updated at container close */
+ return 0;
+}
+
+static int container_close(struct snd_ctl_misc *misc)
+{
+ u32 *store = (u32*) &misc->message[sizeof(u32)];
+ *store = misc->length;
+ return 0;
+}
+
+static int snd_ctl_misc_user(struct snd_ctl_file *ctl,
+ struct snd_ctl_misc __user *_misc)
+{
+ struct snd_ctl_misc *misc;
+ struct snd_card *card = ctl->card;
+ struct snd_kcontrol *kctl;
+ struct snd_ctl_elem_info2 info2;
+ int result=0;
+ int numid;
+ unsigned int received_length;
+ unsigned int tlv_type;
+ unsigned int tlv_length;
+ unsigned int tlv_value;
+ unsigned int container_type;
+ unsigned int container_length;
+
+ misc = kmalloc(2048, GFP_KERNEL);
+ if (misc == NULL)
+ return -ENOMEM;
+
+ /* Only copy _misc: version and length from user-space */
+ if (copy_from_user(misc, _misc, 8)) {
+ result = -EFAULT;
+ goto exit_free;
+ }
+ /* Sanity check */
+ snd_printk("misc->version=%d\n",misc->version);
+ if (misc->version!=1) {
+ result = -EINVAL;
+ goto exit_free;
+ }
+ received_length = misc->length;
+ snd_printk("misc->length=%d\n",misc->length);
+ if (received_length>2040 || received_length<8) {
+ result = -EINVAL;
+ goto exit_free;
+ }
+ /* Copy the entire _misc from user-space */
+ if (copy_from_user(misc, _misc, received_length)) {
+ result = -EFAULT;
+ goto exit_free;
+ }
+ misc->length=0;
+ message_to_uint32(misc, &container_type);
+ snd_printk("container_type=%d\n",container_type);
+ switch (container_type) {
+ case SND_MISC_DB_SCALE:
+ message_to_uint32(misc, &container_length);
+ /* FIXME: Do more sanity checks here */
+ message_to_uint32(misc, &tlv_type);
+ snd_printk("tlv_type=%d\n",tlv_type);
+ switch (tlv_type) {
+ case SND_MISC_ELEM_NUMID:
+ message_to_uint32(misc, &tlv_length);
+ snd_printk("tlv_length=%d\n",tlv_length);
+ if (tlv_length != 4) {
+ result = -EINVAL;
+ goto exit_free;
+ }
+ message_to_uint32(misc, &tlv_value);
+ snd_printk("tlv_value=%d\n",tlv_value);
+ break;
+ default:
+ result = -EINVAL;
+ goto exit_free;
+ break;
+ }
+ break;
+ default:
+ result = -EINVAL;
+ goto exit_free;
+ }
+ numid=tlv_value;
+ //snd_printk("numid=%d\n", tlv_value);
+ down_read(&card->controls_rwsem);
+ kctl = snd_ctl_find_numid(card, numid);
+ if (kctl == NULL) {
+ snd_printk("stop 1\n");
+ result = -ENOENT;
+ goto exit_up;
+ }
+ if ( !(kctl->info2) ) {
+ snd_printk("stop 2\n");
+ result = -EINVAL;
+ goto exit_up;
+ }
+ if (kctl->info2(kctl, 1, &info2)) {
+ snd_printk("stop 3\n");
+ result = -EINVAL;
+ goto exit_up;
+ }
+ ;
+ snd_printk("ok 1\n");
+ misc->version=1;
+ misc->length=0;
+ container_open(misc, SND_MISC_DB_SCALE);
+ add_message_tlv_to_container(misc, info2.length, info2.message);
+ container_close(misc);
+ if (copy_to_user(_misc, misc, received_length))
+ result = -EFAULT;
+ snd_printk("ok 2\n");
+
+exit_up:
+ up_read(&card->controls_rwsem);
+exit_free:
+ kfree(misc);
+exit:
+ return result;
}
static int snd_ctl_elem_list(struct snd_card *card,
@@ -1103,6 +1270,8 @@ static long snd_ctl_ioctl(struct file *f
return snd_ctl_elem_add_user(ctl, argp, 1);
case SNDRV_CTL_IOCTL_ELEM_REMOVE:
return snd_ctl_elem_remove(ctl, argp);
+ case SNDRV_CTL_IOCTL_MISC:
+ return snd_ctl_misc_user(ctl, argp);
case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
return snd_ctl_subscribe_events(ctl, ip);
case SNDRV_CTL_IOCTL_POWER:
diff -r 551da56a592c include/asound.h
--- a/include/asound.h Fri May 19 19:22:34 2006 +0200
+++ b/include/asound.h Sat May 27 19:53:59 2006 +0100
@@ -818,6 +818,44 @@ struct snd_ctl_elem_value {
unsigned char reserved[128-sizeof(struct timespec)];
};
+struct snd_ctl_misc {
+ u32 version;
+ u32 length;
+ unsigned char message[];
+};
+
+struct snd_ctl_elem_db_scale_type1 {
+ /* Type=1 for simple
+ * dB = (X * db_per_devision) - db_offset
+ * This equation is used instead of a more normal
+ * dB = (( X - db_offset) * db_numerator) / db_denominator
+ * in order to avoid any devision by zero possibilities,
+ * save 4 bytes per db_scale and avoid floating point maths.
+ *
+ * Types >= 2 are for future more complex conversion functions.
+ * All types have to have a length value, in case the user land
+ * alsa lib does not yet understand the type. The length field allows
+ * user land to safely skip this TLV.
+ */
+ u32 type; /* 1 */
+ u32 length; /* 12 */
+ s32 db_per_devision; /* Use db per devision * 100 */
+ s32 db_offset; /* Use dB offset * 100. This identifies the 0dB point */
+ s32 db_mute; /* The value, before conversion, that is equivalent to MUTE */
+};
+
+struct snd_ctl_elem_info2 {
+ u32 length;
+ unsigned char *message;
+};
+
+
+#define SND_MISC_DB_SCALE 2
+/* Request */
+#define SND_MISC_ELEM_NUMID 2
+/* Response */
+#define SND_MISC_ELEM_DB_SCALE 2
+
enum {
SNDRV_CTL_IOCTL_PVERSION = _IOR('U', 0x00, int),
SNDRV_CTL_IOCTL_CARD_INFO = _IOR('U', 0x01, struct snd_ctl_card_info),
@@ -833,6 +871,7 @@ enum {
SNDRV_CTL_IOCTL_ELEM_REMOVE = _IOWR('U', 0x19, struct snd_ctl_elem_id),
SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE = _IOWR('U', 0x20, int),
SNDRV_CTL_IOCTL_HWDEP_INFO = _IOR('U', 0x21, struct snd_hwdep_info),
+ SNDRV_CTL_IOCTL_MISC = _IOR('U', 0x22, struct snd_ctl_misc),
SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE = _IOR('U', 0x30, int),
SNDRV_CTL_IOCTL_PCM_INFO = _IOWR('U', 0x31, struct snd_pcm_info),
SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE = _IOW('U', 0x32, int),
diff -r 551da56a592c include/control.h
--- a/include/control.h Fri May 19 19:22:34 2006 +0200
+++ b/include/control.h Sat May 27 19:53:59 2006 +0100
@@ -30,6 +30,7 @@ typedef int (snd_kcontrol_info_t) (struc
typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo);
typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
+typedef int (snd_kcontrol_info2_t) (struct snd_kcontrol * kcontrol, int type, struct snd_ctl_elem_info2 * uinfo);
struct snd_kcontrol_new {
snd_ctl_elem_iface_t iface; /* interface identifier */
@@ -42,6 +43,7 @@ struct snd_kcontrol_new {
snd_kcontrol_info_t *info;
snd_kcontrol_get_t *get;
snd_kcontrol_put_t *put;
+ snd_kcontrol_info2_t *info2;
unsigned long private_value;
};
@@ -58,6 +60,7 @@ struct snd_kcontrol {
snd_kcontrol_info_t *info;
snd_kcontrol_get_t *get;
snd_kcontrol_put_t *put;
+ snd_kcontrol_info2_t *info2;
unsigned long private_value;
void *private_data;
void (*private_free)(struct snd_kcontrol *kcontrol);
diff -r 551da56a592c pci/ca0106/ca0106_mixer.c
--- a/pci/ca0106/ca0106_mixer.c Fri May 19 19:22:34 2006 +0200
+++ b/pci/ca0106/ca0106_mixer.c Sat May 27 19:53:59 2006 +0100
@@ -362,6 +362,28 @@ static int snd_ca0106_spdif_put(struct s
return change;
}
+static struct snd_ctl_elem_db_scale_type1 db_scale_1 =
+{
+ /* Scale from -51.50 dB to +12.00 dB in steps of 0.25 dB. 256 steps. */
+ .type=1,
+ .length=12,
+ .db_per_devision=25,
+ .db_offset=5175,
+ .db_mute=0
+};
+
+static int snd_ca0106_info2_db_scale_1(struct snd_kcontrol *kcontrol, int type,
+ struct snd_ctl_elem_info2 *uinfo)
+{
+ if (type==1) {
+ uinfo->length=sizeof(struct snd_ctl_elem_db_scale_type1);
+ uinfo->message=(unsigned char*) &db_scale_1;
+ return 0;
+ }
+ return -EINVAL; /* type not implemented */
+}
+
+
static int snd_ca0106_volume_info(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_info *uinfo)
{
@@ -466,13 +488,14 @@ static int snd_ca0106_i2c_volume_put(str
return change;
}
-#define CA_VOLUME(xname,chid,reg) \
+#define CA_VOLUME(xname,chid,reg,db_function) \
{ \
.iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, \
.info = snd_ca0106_volume_info, \
.get = snd_ca0106_volume_get, \
.put = snd_ca0106_volume_put, \
- .private_value = ((chid) << 8) | (reg) \
+ .private_value = ((chid) << 8) | (reg), \
+ .info2 = db_function \
}
#define I2C_VOLUME(xname,chid) \
@@ -487,25 +510,33 @@ static int snd_ca0106_i2c_volume_put(str
static struct snd_kcontrol_new snd_ca0106_volume_ctls[] __devinitdata = {
CA_VOLUME("Analog Front Playback Volume",
- CONTROL_FRONT_CHANNEL, PLAYBACK_VOLUME2),
+ CONTROL_FRONT_CHANNEL, PLAYBACK_VOLUME2,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("Analog Rear Playback Volume",
- CONTROL_REAR_CHANNEL, PLAYBACK_VOLUME2),
+ CONTROL_REAR_CHANNEL, PLAYBACK_VOLUME2,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("Analog Center/LFE Playback Volume",
- CONTROL_CENTER_LFE_CHANNEL, PLAYBACK_VOLUME2),
+ CONTROL_CENTER_LFE_CHANNEL, PLAYBACK_VOLUME2,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("Analog Side Playback Volume",
- CONTROL_UNKNOWN_CHANNEL, PLAYBACK_VOLUME2),
-
+ CONTROL_UNKNOWN_CHANNEL, PLAYBACK_VOLUME2,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("IEC958 Front Playback Volume",
- CONTROL_FRONT_CHANNEL, PLAYBACK_VOLUME1),
+ CONTROL_FRONT_CHANNEL, PLAYBACK_VOLUME1,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("IEC958 Rear Playback Volume",
- CONTROL_REAR_CHANNEL, PLAYBACK_VOLUME1),
+ CONTROL_REAR_CHANNEL, PLAYBACK_VOLUME1,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("IEC958 Center/LFE Playback Volume",
- CONTROL_CENTER_LFE_CHANNEL, PLAYBACK_VOLUME1),
+ CONTROL_CENTER_LFE_CHANNEL, PLAYBACK_VOLUME1,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("IEC958 Unknown Playback Volume",
- CONTROL_UNKNOWN_CHANNEL, PLAYBACK_VOLUME1),
+ CONTROL_UNKNOWN_CHANNEL, PLAYBACK_VOLUME1,
+ &snd_ca0106_info2_db_scale_1),
CA_VOLUME("CAPTURE feedback Playback Volume",
- 1, CAPTURE_CONTROL),
+ 1, CAPTURE_CONTROL,
+ &snd_ca0106_info2_db_scale_1),
I2C_VOLUME("Phone Capture Volume", 0),
I2C_VOLUME("Mic Capture Volume", 1),
diff -r d5a6770e7faf include/control.h
--- a/include/control.h Fri May 19 18:26:41 2006 +0200
+++ b/include/control.h Sat May 27 19:54:17 2006 +0100
@@ -52,6 +52,9 @@ typedef struct snd_aes_iec958 {
/** CTL card info container */
typedef struct _snd_ctl_card_info snd_ctl_card_info_t;
+
+/** CTL misc container */
+typedef struct _snd_ctl_misc snd_ctl_misc_t;
/** CTL element identifier container */
typedef struct _snd_ctl_elem_id snd_ctl_elem_id_t;
@@ -212,6 +215,7 @@ int snd_ctl_poll_descriptors_revents(snd
int snd_ctl_poll_descriptors_revents(snd_ctl_t *ctl, struct pollfd *pfds, unsigned int nfds, unsigned short *revents);
int snd_ctl_subscribe_events(snd_ctl_t *ctl, int subscribe);
int snd_ctl_card_info(snd_ctl_t *ctl, snd_ctl_card_info_t *info);
+int snd_ctl_misc(snd_ctl_t *ctl, snd_ctl_misc_t *misc);
int snd_ctl_elem_list(snd_ctl_t *ctl, snd_ctl_elem_list_t * list);
int snd_ctl_elem_info(snd_ctl_t *ctl, snd_ctl_elem_info_t *info);
int snd_ctl_elem_read(snd_ctl_t *ctl, snd_ctl_elem_value_t *value);
@@ -485,6 +489,8 @@ int snd_hctl_elem_info(snd_hctl_elem_t *
int snd_hctl_elem_info(snd_hctl_elem_t *elem, snd_ctl_elem_info_t * info);
int snd_hctl_elem_read(snd_hctl_elem_t *elem, snd_ctl_elem_value_t * value);
int snd_hctl_elem_write(snd_hctl_elem_t *elem, snd_ctl_elem_value_t * value);
+int snd_hctl_elem_misc(snd_hctl_elem_t *elem, snd_ctl_misc_t * misc);
+int snd_hctl_elem_get_db_gain(snd_hctl_elem_t *elem, long volume, long *db_gain);
snd_hctl_t *snd_hctl_elem_get_hctl(snd_hctl_elem_t *elem);
diff -r d5a6770e7faf include/local.h
--- a/include/local.h Fri May 19 18:26:41 2006 +0200
+++ b/include/local.h Sat May 27 19:54:17 2006 +0100
@@ -46,6 +46,7 @@
#define _snd_pcm_status sndrv_pcm_status
#define _snd_ctl_card_info sndrv_ctl_card_info
+#define _snd_ctl_misc sndrv_ctl_misc
#define _snd_ctl_elem_id sndrv_ctl_elem_id
#define _snd_ctl_elem_list sndrv_ctl_elem_list
#define _snd_ctl_elem_info sndrv_ctl_elem_info
diff -r d5a6770e7faf include/sound/asound.h
--- a/include/sound/asound.h Fri May 19 18:26:41 2006 +0200
+++ b/include/sound/asound.h Sat May 27 19:54:17 2006 +0100
@@ -26,6 +26,7 @@
#if defined(LINUX) || defined(__LINUX__) || defined(__linux__)
#include <linux/ioctl.h>
+#include <inttypes.h>
#ifdef __KERNEL__
@@ -847,6 +848,18 @@ struct sndrv_ctl_elem_value {
unsigned char reserved[128-sizeof(struct timespec)];
};
+struct sndrv_ctl_misc {
+ uint32_t version; /* This should be uint32_t */
+ uint32_t length; /* This should be uint32_t */
+ unsigned char message[];
+};
+
+#define SND_MISC_DB_SCALE 2
+/* Request */
+#define SND_MISC_ELEM_NUMID 2
+/* Response */
+#define SND_MISC_ELEM_DB_SCALE_TYPE1 1
+
enum {
SNDRV_CTL_IOCTL_PVERSION = _IOR('U', 0x00, int),
SNDRV_CTL_IOCTL_CARD_INFO = _IOR('U', 0x01, struct sndrv_ctl_card_info),
@@ -862,6 +875,7 @@ enum {
SNDRV_CTL_IOCTL_ELEM_REMOVE = _IOWR('U', 0x19, struct sndrv_ctl_elem_id),
SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE = _IOWR('U', 0x20, int),
SNDRV_CTL_IOCTL_HWDEP_INFO = _IOR('U', 0x21, struct sndrv_hwdep_info),
+ SNDRV_CTL_IOCTL_MISC = _IOR('U', 0x22, struct sndrv_ctl_misc),
SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE = _IOR('U', 0x30, int),
SNDRV_CTL_IOCTL_PCM_INFO = _IOWR('U', 0x31, struct sndrv_pcm_info),
SNDRV_CTL_IOCTL_PCM_PREFER_SUBDEVICE = _IOW('U', 0x32, int),
diff -r d5a6770e7faf src/control/control.c
--- a/src/control/control.c Fri May 19 18:26:41 2006 +0200
+++ b/src/control/control.c Sat May 27 19:54:17 2006 +0100
@@ -234,6 +234,20 @@ int snd_ctl_card_info(snd_ctl_t *ctl, sn
{
assert(ctl && info);
return ctl->ops->card_info(ctl, info);
+}
+
+/**
+ * \brief Get/Set misc related information
+ * \param ctl CTL handle
+ * \param misc pointer
+ * \return 0 on success otherwise a negative error code
+ */
+int snd_ctl_misc(snd_ctl_t *ctl, snd_ctl_misc_t *misc)
+{
+ int err;
+ assert(ctl && misc);
+ err = ctl->ops->misc(ctl, misc);
+ return err;
}
/**
diff -r d5a6770e7faf src/control/control_hw.c
--- a/src/control/control_hw.c Fri May 19 18:26:41 2006 +0200
+++ b/src/control/control_hw.c Sat May 27 19:54:17 2006 +0100
@@ -128,6 +128,16 @@ static int snd_ctl_hw_card_info(snd_ctl_
return 0;
}
+static int snd_ctl_hw_misc(snd_ctl_t *handle, snd_ctl_misc_t *misc)
+{
+ snd_ctl_hw_t *hw = handle->private_data;
+ if (ioctl(hw->fd, SNDRV_CTL_IOCTL_MISC, misc) < 0) {
+ //SYSERR("SNDRV_CTL_IOCTL_MISC failed");
+ return -errno;
+ }
+ return 0;
+}
+
static int snd_ctl_hw_elem_list(snd_ctl_t *handle, snd_ctl_elem_list_t *list)
{
snd_ctl_hw_t *hw = handle->private_data;
@@ -296,6 +306,7 @@ snd_ctl_ops_t snd_ctl_hw_ops = {
.async = snd_ctl_hw_async,
.subscribe_events = snd_ctl_hw_subscribe_events,
.card_info = snd_ctl_hw_card_info,
+ .misc = snd_ctl_hw_misc,
.element_list = snd_ctl_hw_elem_list,
.element_info = snd_ctl_hw_elem_info,
.element_add = snd_ctl_hw_elem_add,
diff -r d5a6770e7faf src/control/control_local.h
--- a/src/control/control_local.h Fri May 19 18:26:41 2006 +0200
+++ b/src/control/control_local.h Sat May 27 19:54:17 2006 +0100
@@ -27,6 +27,7 @@ typedef struct _snd_ctl_ops {
int (*async)(snd_ctl_t *handle, int sig, pid_t pid);
int (*subscribe_events)(snd_ctl_t *handle, int subscribe);
int (*card_info)(snd_ctl_t *handle, snd_ctl_card_info_t *info);
+ int (*misc)(snd_ctl_t *handle, snd_ctl_misc_t *info);
int (*element_list)(snd_ctl_t *handle, snd_ctl_elem_list_t *list);
int (*element_info)(snd_ctl_t *handle, snd_ctl_elem_info_t *info);
int (*element_add)(snd_ctl_t *handle, snd_ctl_elem_info_t *info);
diff -r d5a6770e7faf src/control/hcontrol.c
--- a/src/control/hcontrol.c Fri May 19 18:26:41 2006 +0200
+++ b/src/control/hcontrol.c Sat May 27 19:54:17 2006 +0100
@@ -49,6 +49,7 @@ to reduce overhead accessing the real co
#include <fcntl.h>
#include <sys/ioctl.h>
#include <pthread.h>
+#include <inttypes.h>
#ifndef DOC_HIDDEN
#define __USE_GNU
#endif
@@ -757,6 +758,181 @@ int snd_hctl_handle_events(snd_hctl_t *h
return count;
}
+
+static int uint32_to_message(snd_ctl_misc_t *misc, uint32_t value)
+{
+ unsigned int pointer = misc->length;
+ uint32_t *store = (uint32_t*) &misc->message[pointer];
+ *store = value;
+ misc->length += sizeof(uint32_t);
+ return 0;
+}
+
+static int message_to_uint32(snd_ctl_misc_t *misc, uint32_t *value)
+{
+ unsigned int pointer = misc->length;
+ uint32_t *store = (uint32_t*) &misc->message[pointer];
+ *value = *store;
+ misc->length += sizeof(uint32_t);
+ return 0;
+}
+
+
+static int add_int32_tlv_to_container(snd_ctl_misc_t *misc, uint32_t type, uint32_t value)
+{
+ uint32_to_message(misc, type);
+ uint32_to_message(misc, 4);
+ uint32_to_message(misc, value);
+ /* FIXME: Check for overflows */
+ return 0;
+}
+
+static int add_message_tlv_to_container(
+ snd_ctl_misc_t *misc, uint32_t length, unsigned char *message)
+{
+ unsigned int pointer = misc->length;
+ unsigned int n;
+ for(n=0; n<length; n++) {
+ misc->message[pointer++] = message[n];
+ }
+ misc->length = pointer;
+ /* FIXME: Check for overflows */
+ return 0;
+}
+
+
+static int container_open(snd_ctl_misc_t *misc, uint32_t type)
+{
+ uint32_to_message(misc, type);
+ uint32_to_message(misc, 0); /* This gets updated at container close */
+ return 0;
+}
+
+static int container_close(snd_ctl_misc_t *misc)
+{
+ uint32_t *store = (uint32_t*) &misc->message[sizeof(uint32_t)];
+ *store = misc->length;
+ return 0;
+}
+
+
+struct snd_ctl_elem_db_scale_type1 {
+ /* Type=1 for simple
+ * dB = (X * db_per_devision) - db_offset
+ * This equation is used instead of a more normal
+ * dB = (( X - db_offset) * db_numerator) / db_denominator
+ * in order to avoid any devision by zero possibilities,
+ * save 4 bytes per db_scale and avoid floating point maths.
+ *
+ * Types >= 2 are for future more complex conversion functions.
+ * All types have to have a length value, in case the user land
+ * alsa lib does not yet understand the type. The length field allows
+ * user land to safely skip this TLV.
+ */
+ uint32_t type; /* 1 */
+ uint32_t length; /* 12 */
+ int32_t db_per_devision; /* Use db per devision * 100 */
+ int32_t db_offset; /* Use dB offset * 100. This identifies the 0dB point */
+ int32_t db_mute; /* The value, before conversion, that is equivalent to MUTE */
+};
+
+/**
+ * \brief Get misc information for an HCTL element
+ * \param elem HCTL element
+ * \param info HCTL element information
+ * \return 0 otherwise a negative error code on failure
+ */
+int snd_hctl_elem_get_db_gain(snd_hctl_elem_t *elem, long volume, long *db_gain)
+{
+ snd_ctl_misc_t *misc;
+ int err=0;
+ unsigned int received_length;
+ unsigned int tlv_type;
+ unsigned int tlv_length;
+ unsigned int container_type;
+ unsigned int container_length;
+ struct snd_ctl_elem_db_scale_type1 *db_scale_1;
+
+ assert(elem);
+ assert(elem->hctl);
+ misc=malloc(2048);
+ if (misc == NULL) {
+ err = -ENOMEM;
+ return err;
+ }
+ misc->version=1;
+ misc->length=0;
+ container_open(misc, SND_MISC_DB_SCALE);
+ add_int32_tlv_to_container(misc, SND_MISC_ELEM_NUMID, elem->id.numid);
+ container_close(misc);
+ misc->length=2040;
+
+ err = snd_ctl_misc(elem->hctl->ctl, misc);
+ if (err) goto _err;
+
+ received_length = misc->length;
+ misc->length=0;
+ message_to_uint32(misc, &container_type);
+ switch (container_type) {
+ case SND_MISC_DB_SCALE:
+ message_to_uint32(misc, &container_length);
+ db_scale_1 = (struct snd_ctl_elem_db_scale_type1*) &misc->message[misc->length];
+ /* FIXME: Do more sanity checks here */
+ message_to_uint32(misc, &tlv_type);
+ switch (tlv_type) {
+ case SND_MISC_ELEM_DB_SCALE_TYPE1:
+ message_to_uint32(misc, &tlv_length);
+ if (tlv_length != 12) {
+ err = -EINVAL;
+ goto _err;
+ }
+ misc->length+=tlv_length;
+ if (volume == db_scale_1->db_mute) {
+ *db_gain=-9999999; /* Muted */
+ break;
+ }
+ /* Scale ca0106: from -51.50 dB to +12.00 dB in steps of 0.75 dB. 256 steps. */
+ /* Scale emu10k1 dsp controls: from -39.60 dB to 0.00 dB in steps of 0.4 dB. 100 steps. */
+ *db_gain=(volume * db_scale_1->db_per_devision) - db_scale_1->db_offset;
+ break;
+ default:
+ err = -EINVAL;
+ goto _err;
+ break;
+ }
+ break;
+ default:
+ err = -EINVAL;
+ goto _err;
+ }
+
+_err:
+ free(misc);
+ return err;
+#if 0
+ switch (tlv_value) {
+ case 1: /* Scale from -51.50 dB to +12.00 dB in steps of 0.75 dB. 256 steps. */
+ if (volume == 0) {
+ *db_gain=-9999999; /* Muted */
+ break;
+ }
+ *db_gain=(volume * 25) - 5175; /* For ca0106 controls */
+ break;
+ case 2: /* Scale from -39.60 dB to 0.00 dB in steps of 0.4 dB. 100 steps. */
+ if (volume == 0) {
+ *db_gain=-9999999; /* Muted */
+ break;
+ }
+ *db_gain=(volume * 40) - 4000; /* For emu10k1 dsp controls */
+ break;
+ default:
+ *db_gain=-9999999; /* Muted */
+ return 1;
+ }
+ return 0;
+#endif
+}
+
/**
* \brief Get information for an HCTL element
* \param elem HCTL element
diff -r d5a6770e7faf src/mixer/simple_none.c
--- a/src/mixer/simple_none.c Fri May 19 18:26:41 2006 +0200
+++ b/src/mixer/simple_none.c Sat May 27 19:54:17 2006 +0100
@@ -971,12 +971,41 @@ static int get_volume_ops(snd_mixer_elem
return 0;
}
-static int get_dB_ops(snd_mixer_elem_t *elem ATTRIBUTE_UNUSED,
- int dir ATTRIBUTE_UNUSED,
- snd_mixer_selem_channel_id_t channel ATTRIBUTE_UNUSED,
- long *value ATTRIBUTE_UNUSED)
-{
- return -ENXIO;
+static int get_dB_ops(snd_mixer_elem_t *elem,
+ int dir,
+ snd_mixer_selem_channel_id_t channel,
+ long *value)
+{
+ selem_none_t *s = snd_mixer_elem_get_private(elem);
+ selem_ctl_t *c;
+ int err=-EINVAL;
+ long volume, db_gain;
+ if (dir==SM_PLAY) {
+ c = &s->ctls[CTL_PLAYBACK_VOLUME];
+ if (c->type==2) {
+ if (get_volume_ops(elem, dir, channel, &volume))
+ goto _err;
+ if ((err = snd_hctl_elem_get_db_gain(c->elem, volume, &db_gain)) < 0)
+ goto _err;
+ } else
+ goto _err;
+ } else if (dir==SM_CAPT) {
+ c = &s->ctls[CTL_CAPTURE_VOLUME];
+ if (c->type==2) {
+ if (get_volume_ops(elem, dir, channel, &volume))
+ goto _err;
+ if ((err = snd_hctl_elem_get_db_gain(c->elem, volume, &db_gain)) < 0)
+ goto _err;
+ } else
+ goto _err;
+
+ } else
+ goto _err;
+ err=0;
+ *value=db_gain;
+_err:
+ //if (err) printf("get_dB_ops:err=%d\n",err);
+ return err;
}
static int get_switch_ops(snd_mixer_elem_t *elem, int dir,
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