Intel hasn't been very fortunate in the smartphone chipset business. Despite dominating the personal computing semiconductor space, the company failed to gain traction in mobile in time and struggled to catch up afterward despite trying to crack the entry code from different angles: wearables, IoT, tablets, phones, and so on. Eventually, Intel sort of threw in the towel and decided to close its Atom business and take its time to regroup and think of other ways to tackle the issue.
Its foundry business seems to be the key. See, aside from offering platforms and architectures for chipsets, Intel also has a small side business, Intel Custom Foundry, which produces chipsets for other chipmakers.