Quote from the source for this card in alsa-firmware:
// Echo Digital Audio does not disclose the source code from which these
// firmware images are derived. Permission is hereby granted for the
// distribution of these firmware images as part of the Linux kernel or
// other GPL project in text or binary
// form as required.
I believe it could be safely added to linux-firmware.
Quote from the source for this card in alsa-firmware:
// Echo Digital Audio does not disclose the source code from which these
// firmware images are derived. Permission is hereby granted for the
// distribution of these firmware images as part of the Linux kernel or
// other GPL project in text or binary
// form as required.
I believe it could be safely added to linux-firmware.