Sri Kalahasti Bhakta Kanappa Story as stated in Sri Kalahasti Mahatyam.
A number of Chenchus (tribal sect) who were dominant over tribals lived in the village Vudumuru. Natha-Natha was the chieftain of the Chenchus. Natha-Natha and His wife, Tande were blessed with a boy called Tinna. Tinna was good at archery and hunting. One day Tinna along with his companions went for hunting in the forest surrounding the Agastya Hill and Dakshina Kailasa ( Sri Kalahasti). Tinna was tired and slept under a tree. Lord Siva appeared in his dreams and directed him to offer prayers to the Siva Linga located on the banks of Mogileru (Swarnamukhi). Tinna did not pay much attention to his dream and left home. Next day, he happened to see a wild boar and started chasing it. The chasing led him to the place which he had in his dream. Tinna recollected his dream and looked at the Linga. The Linga, which was in the forlorn place was totally neglected, made Tinna very sad. Tinna innocently prayed Lord to come stay with him in his village. But the Linga, in spite of the sincere and wholehearted request of Tinna, kept silent. Tinna companions asked him to return to the village but Tinna reluctant in moving. His companions returned to their village after several requests. Thenceforth Tinna started guarding the Linga and taking care of it.
He used to hunt and offer fresh meat to the Lord. He was bathing the Linga with the mouthful of water brought by him from the Swarnamukhi river. After few days a Siva Brahmana who saw the Linga by change was grieved to find that someone had desecrated the Linga by offering the meat to it. He cleaned the place and performed Prayaschitta and worshipped the Linga according to Vedic rites and went away. Tinna came for worship, swept away the leaves and flowers placed on the Linga with his footwear and bathed the Linga and offered meat in his usual way. This went on for four days and Siva Brahmana was unhappy with the rituals performed to the Linga. Being deeply devoted to Lord Siva he even questioned Him how the Lord was tolerating this kind of treatment and that who was responsible for desecration. Lord Siva appeared in his dream and asked him to hide behind the Linga and see the Love and devotion of a true devotee.
As instructed, Brahmana hid behind the Linga and watching curiously. After a while arrived there with meat and water in his mouth. He first bathed the Linga and placed the flesh in front of it. Suddenly he was startled to see the flow of blood from one of the eyes of the Linga. Tinna decided that Lord was affected by some eye disease and he hurried into the forest and brought some medical herbs and applied them to the affected eye of the Linga. Even after applying the medicine, the blood continued to flow down the eye. Thereupon he gouged out one of his eyes and replaced it on the affected eye. The eye immediately stopped bleeding. To his surprise, the other healthy began to bleed. Perturbed by this, Tinna marked the affected eye with his sandaled foot and attempted to pluck out his remaining eye with an arrow. On seeing this unusual act of devotion, Siva arose from the Linga, commended his dedication and finally took Tinna into Him. Since he offered his eye (Kannu in Telugu) to the Lord, he came to be known as Kanappa. The Siva Brahmana was also blessed by the Lord