Step 1: Define Khanqah:
A khanqah was the hospice/residence of a Sufi Chishti saint, serving as a centre for teaching, lodging travellers and disciples, and community life -- open, in principle, to visitors of any faith or social background.
Step 2: Describe its social role:
It functioned as a place of refuge and charity, running a langar (free community kitchen), and acted as an informal meeting ground where rulers, nobles and commoners alike could seek the saint's blessing.
Step 3: Describe Chishti forms of worship:
Chishti worship (ibadat) emphasised dhikr (remembrance/repetition of God's names), fasting, and especially sama -- gatherings of devotional music (qawwali) believed to induce spiritual ecstasy and closeness to God.
Step 4: Note their philosophy:
Chishti saints stressed humility, service to the poor, voluntary poverty, and a personal, love-centred relationship with God rather than dependence on royal patronage or worldly power.
Final Answer:
\[ \boxed{\text{Chishti Khanqah: an open hospice for teaching and charity; Chishti worship centred on dhikr and sama (devotional music)}} \]