He came to the Prophet ﷺ to call him for the dawn prayer. He was told, "He is asleep." So he said, "Prayer is better than sleep, prayer is better than sleep." This was then established in the call for the dawn prayer, and the practice has remained so ever since.
حدثنا عمرو بن رافع حدثنا عبد الله بن المبارك عن معمر عن الزهري عن سعيد بن المسيب
أنه أتى النبي ﷺ يؤذنه بصلاة الفجر فقيل هو نائم فقال الصلاة خير من النوم الصلاة خير من النوم فأقرت في تأذين الفجر فثبت الأمر على ذلك
No references are available.
Its chain of transmission is daif. Busiri said, "Its narrators are trustworthy, but there is a break in it, Saeed bin Musayab did not hear from Bilal."