This is Matsyendranatha, one of the Saivite ascetics and the founder of the Nath tradition. That tradition was originally based on tantric rituals, Hatha Yoga, and Alchemy.

Matsyendranatha was thought to have been born in East Bengal and that tradition has spread all over India, Nepal and Tibet. He was the teacher of better known Goraknath.

In this case, he is identified by the fish he is sitting on and the Trishul.

In South India, the popularity of the Nath tradition increased during the Vijayanagar period (14th to 16th century), and it has since continued. Most temples in South India have relief sculptures of Nath Siddhas in the Mahamandapas or on the outer walls. The photo below is by me, and it is from the Someshwara Temple, Ulsoor, Bangalore.

Some of the other temples where Nath Siddhas sculptures can be found are Srisailam Mallikarjuna Swamy Temple, Hampi ruins and Vidhyasankara Temple, Sringeri.

The crown is an unusual feature for an ascetic and so is his sitting astride. Normally he sits sideways as in the Someshwara example.

It is unusual to find a bronze of Matsyendranatha and that too in good condition. This bronze may be dated to the 18th-19th century. It is about 12.5 cm tall.