Passage: Despite being freely available, companies profit from Linux. These companies, many of which are also members of the Linux Foundation, invest substantial resources into the advancement and development of Linux, in order to make it suited for various application areas. This includes hardware donations for driver developers, cash donations for people who develop Linux software, and the employment of Linux programmers at the company. Some examples are Dell, IBM and Hewlett-Packard, which validate, use and sell Linux on their own servers, and Red Hat and SUSE, which maintain their own enterprise distributions. Likewise, Digia supports Linux by the development and LGPL licensing of Qt, which makes the development of KDE possible, and by employing some of the X and KDE developers.

Question: For what software did developers recieve cash donations?
Linux