/**
* \brief Set TLV value for an HCTL element
* \param elem HCTL element
* \param tlv TLV array for value
* \retval 0 on success
* \retval >1 on success when value was changed
* \retval <0 a negative error code on failure
*/
int snd_hctl_elem_tlv_write(snd_hctl_elem_t *elem, const unsigned int *tlv)
{
assert(elem);
assert(tlv);
assert(tlv[1] >= 4);
return snd_ctl_elem_tlv_write(elem->hctl->ctl, &elem->id, tlv);
}
static int check_tlv(struct elem_set_trial *trial)
{
unsigned int orig[8], curr[8];
int err;
/*
* See a layout of 'struct snd_ctl_tlv'. I don't know the reason to
* construct this buffer with the same layout. It should be abstracted
* inner userspace library...
*/
orig[0] = snd_ctl_elem_id_get_numid(trial->id);
orig[1] = 6 * sizeof(orig[0]);
orig[2] = 'a';
orig[3] = 'b';
orig[4] = 'c';
orig[5] = 'd';
orig[6] = 'e';
orig[7] = 'f';
/*
* In in-kernel implementation, write and command operations are the
* same for an element set added by userspace applications. Here, I
* use write.
*/
err = snd_ctl_elem_tlv_write(trial->handle, trial->id,
(const unsigned int *)orig);
if (err < 0)
return err;
err = snd_ctl_elem_tlv_read(trial->handle, trial->id, curr,
sizeof(curr));
if (err < 0)
return err;
if (memcmp(curr, orig, sizeof(orig)) != 0)
return -EIO;
return 0;
}
static int execute_cset(snd_ctl_t *ctl, const char *cset, unsigned int type)
{
const char *pos;
int err;
snd_ctl_elem_id_t *id;
snd_ctl_elem_value_t *value;
snd_ctl_elem_info_t *info;
unsigned int *res = NULL;
snd_ctl_elem_id_malloc(&id);
snd_ctl_elem_value_malloc(&value);
snd_ctl_elem_info_malloc(&info);
err = __snd_ctl_ascii_elem_id_parse(id, cset, &pos);
if (err < 0)
goto __fail;
while (*pos && isspace(*pos))
pos++;
if (!*pos) {
uc_error("undefined value for cset >%s<", cset);
err = -EINVAL;
goto __fail;
}
snd_ctl_elem_info_set_id(info, id);
err = snd_ctl_elem_info(ctl, info);
if (err < 0)
goto __fail;
if (type == SEQUENCE_ELEMENT_TYPE_CSET_TLV) {
if (!snd_ctl_elem_info_is_tlv_writable(info)) {
err = -EINVAL;
goto __fail;
}
err = read_tlv_file(&res, pos);
if (err < 0)
goto __fail;
err = snd_ctl_elem_tlv_write(ctl, id, res);
if (err < 0)
goto __fail;
} else {
snd_ctl_elem_value_set_id(value, id);
err = snd_ctl_elem_read(ctl, value);
if (err < 0)
goto __fail;
if (type == SEQUENCE_ELEMENT_TYPE_CSET_BIN_FILE)
err = binary_file_parse(value, info, pos);
else
err = snd_ctl_ascii_value_parse(ctl, value, info, pos);
if (err < 0)
goto __fail;
err = snd_ctl_elem_write(ctl, value);
if (err < 0)
goto __fail;
}
err = 0;
__fail:
if (id != NULL)
free(id);
if (value != NULL)
free(value);
if (info != NULL)
free(info);
if (res != NULL)
free(res);
return err;
}
