Here is Rajesh Thakur talking about Sufi songs in Bollywood
Sufi music is the devotional music of the Sufis, inspired by the works of Sufi poets, like Rumi, Hafiz, Bulleh Shah, Amir Khusrow and Khwaja Ghulam Farid.
Qawwali is the most well known form of Sufi music, and is most commonly found in the Sufi culture in South Asia. However, music is also central to the Sema ceremony of the whirling dervishes, which is set to a form of music called Ayin, a vocal and instrumental piece featuring Turkish classical instruments such as the ney (a reed flute). The West African gnawa is another form, and Sufis from Indonesia to Afghanistan to Morocco have made music central to their practices. Some of the Sufi orders have taken an approach more akin to puritan forms of Islam, declaring music to be unhelpful to the Sufi way.
Sufi love songs are often performed as ghazals and Kafi, a solo genre accompanied by percussion and harmonium, using a repertoire of songs by Sufi poets.