Hi Sebastian, On Fri, 26 Nov 2010 19:03:25 +0100, Sebastian Andrzej Siewior wrote: > * Jean Delvare | 2010-11-25 22:52:46 [+0100]: > > >Hi Sebastian, > Hi Jean, > > >> > But my main question is: why do you want a unique (or you probably > >> > meant predictable - adapter numbers are already unique by design) > >> > adapter number in the first place? Other systems apparently are doing > >> > just fine without this. > >> > >> Both. I use this number for the device id. This one has to remain unique > >> or sysfs goes crazy. > > > >Which "device id" are you talking about, please? Of course sysfs > The pci driver [0] has in add_i2c_device() the following construct: > > pdev->id = dev->devfn << 3 | bar; > > I'm talking about this device id. Here I have to remain unique and here I Huh? Is pdev a platform device? So you are instantiating platform devices off a PCI device, and in turn each platform device gets to create an i2c_adapter device? Now I understand why you needed to craft a unique id. I don't quite get why you came up with such a complicated setup in the first place though. What's wrong with just making the i2c_adapter devices direct children of the PCI device? Is this a limitation of of_i2c_register_devices() that it needs platform devices to operate on? > though using the pci id would be a good idea. There should be no other > device using "pxa2xx-i2c" as the device name so I should be safe here. Correct. > >doesn't accept duplicate entries, but as I said already, uniqueness is > > > >Precisions, please. "Match my board description" is awfully vague. > >Don't hesitate to be technical, I'm sure I can understand you ;) > Sorry didn't meant to. As you probably know, by "board description" I > meant struct i2c_board_info & i2c_register_board_info(). This is now > covered by of_i2c_register_devices(&i2c->adap) OK, it's clearer now, thanks. > >> > Fixed i2c adapter numbers are already supported, but it's up to the > >> > platform initialization code to define them, not the i2c adapter driver. > >> > >> I don't want platform init code. > > > >Why? This is what (almost) everybody does when predictable i2c adapter > >numbers are needed. And you said you have platform data, so presumably > >you already have some form of platform init code (even if it's generic > >code with a custom device tree.) > > This sounds good. So I get "pdev->id" from the device tree which should > solve my trouble I have so far. Sounds good. And now you no longer care about i2c adapter numbers - they don't have to be correlated to your platform device numbers. Meanwhile I've updated i2c-tools to support dev minors beyond 255. You should no longer need this, but at least it's ready if we ever need it. Who knows, maybe we'll see a system with more than 255 I2C bus segments someday. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
