My Son Of 12 Yrs. Suffering From ASD With ADHD.

My son of 12 yrs. suffering from ASD with ADHD. He likes to go outside rather than home. If we do not follow his desire for outing frequently, he starts crying and become aggresive. But felt good when goes outside visit specially with me, father.Less language/speech with social engagement available. But since last 5 months-he starts crying just after wake up from Bed in the morning to meet with his uncle(my younger brother) and then cries to go his house to meet his wife.Mentionable, he was in touch with my younger brother at his early childhood upto 7 yrs.In this stage-he always cries and become restless with less food intake. But it switches to another stage within 2 weeks where he is very much pleasant mode with laughing, make fun with all and take food repeatedly at high amount! He is now visibly switching in this 2 stages at a time interval of 2-3 weeks.How it can be treated or what is its reason?
Best regards,
Aminul Islam Khan