Qualcomm Embbeded Software Engineer interview questions

There was a phone screen before the onsite interview. In the phone screen, the interviewer asked a lot of questions about Embedded C, and gave me a link list question to write. The phone screen was almost 6 hours long. On the contrary, there was no link list questions asked, which was a bit shocking. There was also a lunch with manager, which is not evaluated, where the manager talks about the company and position. There is also an HR, where HR tells you about the feedback from the previous interviewers.

I could not pass the phone screen which was my 1st experience and wasn't related to my major (Electrical Engineering). Phone screen took around 30 minutes and there were 5 technical questions and others about my ability based on what I wrote on resume.