Is Vitthala a tribal deity or an avatar of Lord Vishnu?

Is Vitthala a tribal deity or an avatar of Lord Vishnu? Shri Vitthala (Vithoba) is a direct form of Shri Krishna (Shri Narayana) and not just a tribal deity. He is worshipped by Maharashtrians as well as Kannadigas to some extent. In fact there is a well known very very beautiful Marathi Bhajan on Shri Vitthala by Sudhir Phadke ji. (It is one of my favorites- mostly all Maharashtrians would know about this Bhajan). Here are the first few lines with meaning. Kanada Raja Pandharicha Vedanahi Nahi Kalala Meaning. "The king of Kanada, Panduranga, Vitthala is the supreme lord whose greatness cannot be understood even by the Vedas.” Nirakar to Nirguna Ishwara Asa Prakatla Asa Vitevar. Meaning He is the formless Ishwara and is the most divine. This is how the supreme lord of the world descended as Vitthala. Shri Vaishnavacharya Vedanta Desika did mention Panduranga as one of the holiest abodes of Shriman Narayana in his commentary. (others being - Jagannath Puri, Shrirangam, Tirupathi, Kanchipuram) “I am bid by this august assembly composed of saintly men like yourselves, who, in order to witness festivals, have trod far and wide over several holy places like Srirangam, Tirupati, Kanchipura, Tirunarayanapuram, Puroshottama and Panduranga where our (Sarveshvara), the Blessed Lord is installed, - the Lord before whose lotus feet the gem-set diadems of myriads if Devas and Asuras form, as it were, so many waving lights, - the Lord whose vow always is to protect all who seek refuge of Him, whose duties are right-well done with lotus-born Lakshmi cooperate, - Who like the cloud (rain), quencheth the wild-fire of mundane misery.” An interesting fact is that Tenali Rama, wrote the Panduranga Mahatmya in Telugu and was his great devotee. YES! I am talking about the Tenali Rama in the court of Maharaja Krishna Deva Raya whose stories we heard from childhood. I could just get the translation of the beginning of the book which says- Hail unto the dual-armed Purushottama, dwelling in Panduranga! He, the omnipresent essence, manifesting in various forms, known by diverse appellations such as Kesava, Krishna, Rama, Vishnu. He shields all his devotees, bestowing upon them courage. Even Maharaj Krishna deva Raya was initiated into Shri Vaishnava Sampradaya through worship of Shri Vitthala in the form of Shri Venkateshwara. There is this book called as Amyuktamalyada of Krishna Deva Raya which says this- Kṛṣṇadevarāya was thoroughly steeped in the Śrīvaiṣṇava tradition and almost every poem in his great work exudes a sense of his personal devotion. The famous avatārika padyam or invocation verse to his iṣṭa-devata Lord Vĕṅkateśvara is also interpreted as a salutation to Kulaśekhara Āḻvār in his aṁśa-avatāra as the Kaustubha gem. The invocatory decad that ends with an explicit poem about the saints (quoted above), is in fact a sustained evocation of their divine status, and their central importance in the poet‟s heart.