I have never found out who the original poet is. There have been many singers that have rendered these words in various tunes. One of my favorite ones is the way done by the young Nooran sisters (most of the vocals is from Jyoti with support from her sister Sultana).
The context is that the lover whose love remained unrequited has passed away and the lady who he longed for had come to visit his grave. The words are:
“Tumne Jo Meri Kabr Par, Aakar Yun Muskura Diya
Bijli Chamak Kar Gir Padi, Sara Kafan Jala Diya
Main So Raha Tha Chain Se, Yun Hi Kafan E Mazaar Mein,
Yahan Bhi Sataane Aa Gaye, Kisne Pata Bata Diya
Tumne Chadhaye Phool To, Ehsaan Kya Kiya
Humne Tumhare Ishq Mein, Sara Chaman Loota Diya
Pucha Na Jeete Ji Kabhi, Dard E Dil Ka Haal
Aaye Ho Kabr Par Meri, Mitti Mein Jab Mila Diya”
Roughly translated (and as always people with far better understanding of Hindi and Urdu are always welcome to suggest changes / alternatives)
“The moment you came upon my grave, and let that faint smile escape your lips
Lightning struck from the sky, and completely burnt down my shroud
I was sleeping at peace with the world, in the coffin at my tomb,
You have came here too to tease me, Oh! Tell me who gave you my address?
So, you have laid a flower on my tomb; what big favor have you done?
I, lost in your love, had spread out the whole garden for you
When I was alive, not even once you asked after my aching heart
Now you have come to me when I have become one with the ground”