From 8d448162bda5ae3b5ecb26fe50c8fbbeae99faa4 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Fri, 7 Oct 2011 22:38:59 +0200 Subject: [PATCH] ALSA: control: add support for ENUMERATED user space controls Handling of user control elements was implemented for all types except ENUMERATED. This type will be needed for the device-specific mixers of upcoming FireWire drivers. Signed-off-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- include/sound/asound.h | 4 +- sound/core/control.c | 80 +++++++++++++++++++++++++++++++++++-- sound/core/control_compat.c | 4 ++ 3 files changed, 83 insertions(+), 5 deletions(-) diff --git a/include/sound/asound.h b/include/sound/asound.h index 5d6074faa27..a2e4ff5ba9e 100644 --- a/include/sound/asound.h +++ b/include/sound/asound.h @@ -706,7 +706,7 @@ struct snd_timer_tread { * * ****************************************************************************/ -#define SNDRV_CTL_VERSION SNDRV_PROTOCOL_VERSION(2, 0, 6) +#define SNDRV_CTL_VERSION SNDRV_PROTOCOL_VERSION(2, 0, 7) struct snd_ctl_card_info { int card; /* card number */ @@ -803,6 +803,8 @@ struct snd_ctl_elem_info { unsigned int items; /* R: number of items */ unsigned int item; /* W: item number */ char name[64]; /* R: value name */ + __u64 names_ptr; /* W: names list (ELEM_ADD only) */ + unsigned int names_length; } enumerated; unsigned char reserved[128]; } value; diff --git a/sound/core/control.c b/sound/core/control.c index dc2a44048c8..978fe1a8e9f 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -989,7 +989,6 @@ struct user_element { void *tlv_data; /* TLV data */ unsigned long tlv_data_size; /* TLV data size */ void *priv_data; /* private data (like strings for enumerated type) */ - unsigned long priv_data_size; /* size of private data in bytes */ }; static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol, @@ -1001,6 +1000,28 @@ static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol, return 0; } +static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) +{ + struct user_element *ue = kcontrol->private_data; + const char *names; + unsigned int item; + + item = uinfo->value.enumerated.item; + + *uinfo = ue->info; + + item = min(item, uinfo->value.enumerated.items - 1); + uinfo->value.enumerated.item = item; + + names = ue->priv_data; + for (; item > 0; --item) + names += strlen(names) + 1; + strcpy(uinfo->value.enumerated.name, names); + + return 0; +} + static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol, struct snd_ctl_elem_value *ucontrol) { @@ -1055,11 +1076,46 @@ static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol, return change; } +static int snd_ctl_elem_init_enum_names(struct user_element *ue) +{ + char *names, *p; + size_t buf_len, name_len; + unsigned int i; + + if (ue->info.value.enumerated.names_length > 64 * 1024) + return -EINVAL; + + names = memdup_user( + (const void __user *)ue->info.value.enumerated.names_ptr, + ue->info.value.enumerated.names_length); + if (IS_ERR(names)) + return PTR_ERR(names); + + /* check that there are enough valid names */ + buf_len = ue->info.value.enumerated.names_length; + p = names; + for (i = 0; i < ue->info.value.enumerated.items; ++i) { + name_len = strnlen(p, buf_len); + if (name_len == 0 || name_len >= 64 || name_len == buf_len) { + kfree(names); + return -EINVAL; + } + p += name_len + 1; + buf_len -= name_len + 1; + } + + ue->priv_data = names; + ue->info.value.enumerated.names_ptr = 0; + + return 0; +} + static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol) { struct user_element *ue = kcontrol->private_data; - if (ue->tlv_data) - kfree(ue->tlv_data); + + kfree(ue->tlv_data); + kfree(ue->priv_data); kfree(ue); } @@ -1101,7 +1157,10 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, memcpy(&kctl.id, &info->id, sizeof(info->id)); kctl.count = info->owner ? info->owner : 1; access |= SNDRV_CTL_ELEM_ACCESS_USER; - kctl.info = snd_ctl_elem_user_info; + if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) + kctl.info = snd_ctl_elem_user_enum_info; + else + kctl.info = snd_ctl_elem_user_info; if (access & SNDRV_CTL_ELEM_ACCESS_READ) kctl.get = snd_ctl_elem_user_get; if (access & SNDRV_CTL_ELEM_ACCESS_WRITE) @@ -1122,6 +1181,11 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, if (info->count > 64) return -EINVAL; break; + case SNDRV_CTL_ELEM_TYPE_ENUMERATED: + private_size = sizeof(unsigned int); + if (info->count > 128 || info->value.enumerated.items == 0) + return -EINVAL; + break; case SNDRV_CTL_ELEM_TYPE_BYTES: private_size = sizeof(unsigned char); if (info->count > 512) @@ -1143,9 +1207,17 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, ue->info.access = 0; ue->elem_data = (char *)ue + sizeof(*ue); ue->elem_data_size = private_size; + if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) { + err = snd_ctl_elem_init_enum_names(ue); + if (err < 0) { + kfree(ue); + return err; + } + } kctl.private_free = snd_ctl_elem_user_free; _kctl = snd_ctl_new(&kctl, access); if (_kctl == NULL) { + kfree(ue->priv_data); kfree(ue); return -ENOMEM; } diff --git a/sound/core/control_compat.c b/sound/core/control_compat.c index 426874429a5..2bb95a7a880 100644 --- a/sound/core/control_compat.c +++ b/sound/core/control_compat.c @@ -83,6 +83,8 @@ struct snd_ctl_elem_info32 { u32 items; u32 item; char name[64]; + u64 names_ptr; + u32 names_length; } enumerated; unsigned char reserved[128]; } value; @@ -372,6 +374,8 @@ static int snd_ctl_elem_add_compat(struct snd_ctl_file *file, &data32->value.enumerated, sizeof(data->value.enumerated))) goto error; + data->value.enumerated.names_ptr = + (uintptr_t)compat_ptr(data->value.enumerated.names_ptr); break; default: break;