On Tuesday 23 of July 2013 17:14:20 Alan Stern wrote: > On Tue, 23 Jul 2013, Tomasz Figa wrote: > > > If you want to keep the phy struct completely separate from the > > > board > > > file, there's an easy way to do it. Let's say the board file knows > > > about N different PHYs in the system. Then you define an array of N > > > pointers to phys: > > > > > > struct phy *(phy_address[N]); > > > > > > In the platform data for both PHY j and its controller, store > > > > > > &phy_address[j]. The PHY provider passes this cookie to phy_create: > > > cookie = pdev->dev.platform_data; > > > ret = phy_create(phy, cookie); > > > > > > and phy_create simply stores: *cookie = phy. The PHY consumer does > > > > > > much the same the same thing: > > > cookie = pdev->dev.platform_data; > > > phy = phy_get(cookie); > > > > > > phy_get returns *cookie if it isn't NULL, or an ERR_PTR otherwise. > > > > OK, this can work. Again, just technically, because it's rather ugly. > > There's no reason the phy_address things have to be arrays. A separate > individual pointer for each PHY would work just as well. > > > Where would you want to have those phy_address arrays stored? There > > are no board files when booting with DT. Not even saying that you > > don't need to use any hacky schemes like this when you have DT that > > nicely specifies relations between devices. > > If everybody agrees DT has a nice scheme for specifying relations > between devices, why not use that same scheme in the PHY core?
It is already used, for cases when consumer device has a DT node attached. In non-DT case this kind lookup translates loosely to something that is being done in regulator framework - you can't bind devices by pointers, because you don't have those pointers, so you need to use device names. > > Anyway, board file should not be considered as a method to exchange > > data between drivers. It should be used only to pass data from it to > > drivers, not the other way. Ideally all data in a board file should > > be marked as const and __init and dropped after system > > initialization. > > The phy_address things don't have to be defined or allocated in the > board file; they could be set up along with the platform data. There is no platform data when booting with DT. > In any case, this was simply meant to be a suggestion to show that it > is relatively easy to do what you need without using name or ID > strings. Sure. It's good to have different options discussed as well. Best regards, Tomasz -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html