Mishkat al-Masabih 3 Purification كتاب الطهارة 130

وَعَنْ أَنَسٍ قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَتَوَضَّأُ لِكُلِّ صَلَاةٍ وَكَانَ أَحَدُنَا يَكْفِيهِ الْوُضُوءُ مَا لَمْ يُحْدِثْ. رَوَاهُ الدِّرَامِي

Anas said that God’s messenger used to perform ablution for every prayer, but that they made the ablution serve as long as they did nothing which broke the state of ceremonial purity. Darimi transmitted it.