There’s a company, Consonance electronics, which has an interesting product range of solar charging integrated circuits. Some of their products are pretty interesting, for example the CN3722.
It’s a switching charger which can handle output currents up to 5 A. With external resistors the charge current and voltage can be set. The device will switch between a constant current and constant voltage charging mode.
The CN3063 is built into various projects for small solar chargers but it’s for lithium ion and not for LiFePO4.
One project which uses it is the MCHCK project which is about building a 5 $ ARM controller board with USB connection.
Update: the CN3059 and CN3060 are linear charge regulators and provide up to 1 A optimized for LiFePO4, just what’s needed. I’m waiting for samples now.