In Atasehir just before you leave the district there is a Shell gas station. Whether you are heading to TEM or E-5 ( two primary ways out of the district) you drive by this station.
I recently started using this path to work and am happy to see that there is a Kahve Dunyasi coffee station within the market. WC is clean including a hair dryer ( who knows you might need it).
You can also have a quick breakfast as there is a small coffee shop as well.