Are you following the rules with tumbling right now? I've seen a lot of people complain about a lot of "broken" things, and tumbling rarely makes that list. If he's "tired" of you using a skill that you put a lot into being good at, maybe the problem isn't your "overuse" of the skill. It sounds like it might be the DM's inability or lack of desire to put your character into situations that make tumbling more difficult. He could put you in difficult terrain, tight spaces that wouldn't allow tumbling, and a host of other things that would at least make it more difficult for you to succeed at tumbling.
I know that 3.5 isn't perfect, and there's nothing wrong with a group making changes for the good of the whole group. But I have to wonder about a DM who is changing something just because you are successful at it a lot. Isn't that the point of D&D, for the characters to be heroes and succeed at their tasks? In our last campaign, I had a halfling druidic/monk in my group. He became really good at both tumbling and his Low Blow feat. So good, in fact, that they became his signature combat moves. Rather than punish him for putting a lot of work into getting good at a particular skill, I just created some environments that made it more challenging. And I didn't go out of my way to make every encounter anti-tumbling, really probably more like 1 in 5. I just don't think players should be punished for putting a lot of focus into 1 particular skill. Besides, if you are putting a lot of focus into 1 skill, there has to be some other weakness in your character that he could challenge you with, rather than nerf a skill just because you are good at it.
If your DM is fairly new to D&D, just talk to him and tell him you'd rather he added some difficulty to the environments or challenged your characters weaknesses rather than nerf a skill you really like to use and have gotten to be pretty skilled with. From your brief description, it sounds like the DM considers it to be a bit of a DM v.s. Player kind of game. That's not a good environment for everyone to have fun. I always wonder how DM's can get "tired" of their players having a great time and being successful. Isn't that the point of the game?