On Tue, May 21, 2019 at 12:24 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > what is so odd about this code that makes you have to jump through > strange hoops that no other driver has to? > Basically because it creates a regmap which accesses __iomem memory, instead of i2c/spi. This was done because future hardware in the company's pipeline will access device register space through spi, instead of through a parallel memory bus. The lower driver just has to create the appropriate regmap, __iomem or spi, and pass it to the upper driver, which does not have to know about the exact way the h/w gets accessed. So regmap is used as a hw abstraction layer. The issue here is that a regmap context is a 'void *' yet the parallel memory base pointer is 'void __iomem *'. And so the two are incompatible. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
