On Fri, Sep 10, 2010 at 09:54:57PM +0200, Dr. H. Nikolaus Schaller wrote: > Does anyone have an idea or knowledge how initialization of the > i2c subsystem really works in the 2.6.24 kernel? > > As far as I did understand, the platform initialization file just registers > a i2c adapter in some list but does not touch it. > > The function i2c_get_adapter() should search this list to identify the driver > according to some "id" value (which one is this? How is it related to > the initialization structure in the platform file?).
- arch_initcall causes jz_platform_init to be executed - it registers a platform device with id 0 - module_init later causes i2c_adap_jz_init to be called - it registers a platform driver - during registration the list of devices is scanned and all devices with the correct name "jz_i2c" are probed - this causes i2c_jz_probe to be called - it takes the id from the platform_device structure and puts it into the adapter's nr field. - then the adapter is registered, giving it that number > Then, the first device that is probed initializes the i2c adapter. > But that is far beyond the first call to the old-style i2c_open(), i.e. > the adapter is not initialized. The problem is that module_init is way too late for an i2c adapter. Try subsys_initcall instead. Daniel _______________________________________________ Mipsbook-devel mailing list Mipsbook-devel@linuxtogo.org http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/mipsbook-devel
