For crying out loud, He's injured, then has to get match fit, and as has been said already he wasn't a prolific scorer in the league either. Whether his Mrs is homesick or she wants to be back in Spain because he has been having an affair over here doesn't really matter to us, but it's probably better to let him leave if the deal is right in money terms for the club.
If Iheanacho can get a permit then he could be added to the striking roster. Jovetic was missing last season but he can replace Negredo this season. Last year we had Jovetic, Aguero and even Negredo out or unfit for long spells, so with the other strengthening we have done we have a better squad than last year. Silva played as a supporting striker last year in the occasional game and Both Nasri and Toure can be pushed further forward to support a striker. We don't have any problems in letting Negredo go.
There is also the issue with the squad size, we cannot bring anyone in except for homegrown players for the league squad, Negredo was also looking at missing out on the Champions League games too.
Some supporters need to realise that to improve the squad we will need to move on some favourites and it's no use moaning about this player or that player going and acting like spoilt brats. If it's Negredo now, it could be Toure, Dzeko or Nasri next window. Signing new contracts doesn't mean the player will see the term out, it just means we can get a fee if they leave early. As long as the club bring in players to replace those that leave then we as fans should be happy with the direction the club are taking.
Where is Negredo in the current pecking order for City ? If he's 4th choice then there is no problem in bringing in a better player to replace him when one becomes available.