From: David Brownell Date: Tue, 1 May 2007 21:26:31 +0000 (+0200) Subject: i2c: Add i2c_board_info and i2c_new_device() X-Git-Tag: v2.6.22-rc1~1081^2~23 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9c1600eda42e52796f49b36cf15b9debcfd09bea;p=pandora-kernel.git i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell Signed-off-by: Jean Delvare --- Reading git-diff-tree failed