On Thu, Aug 10, 2006 at 04:05:02PM +0200, Drasko Draskovic wrote:
> Hi all.
> Can somebody tell me what is exactly struct platform_device for. I have to
> write driver for some device that sits on AMBA bus, and I do not know if I
> should declare it a n amb_device or plaform_device.
Is there a "amb_device" already created in the kernel? If there is,
please use it.
The platform_device stuff is used for devices that are connected to the
processor with no real bus infrastructure. They should only be used as
a last resort, if there is no other bus structures present for them.
And what is a AMBA bus, I haven't heard of that before.
thanks,
greg k-h
Hi Greg,
sorry for the typo, it should be amba_device instead of amb_device. As a metter of fact, I am trying to implement a I2C driver for the custom design, but which is based on standared ARM926EJ microprocessor, and these have AMBA (Advanced Microprocessor Bus Architecture) inside. Looking around I stumbled upon your writings for LJ, which have been most valuable help! Thank you for these.
My main problem here is writing "adapter" part of the driver, which is to drive the interface, called ApI2c, that sits on AMBA (actuallu APB part of AMBA) on one side and on the other on I2C. I am a bit stuck wondering if this adapter should be declared as amba_device (you can see amba.c in arch/arm) or described somehow different as platform_device. I do not have all the code snippets here wich would make question more clear, but I'll provide these tomorrow with some of my observations and more precise questions.
Thanks again,
--
Drasko DRASKOVIC
Software Developer
Elsys-DESIGN
Belgrade, Serbia
Tel. +381.11.311.5252
Fax. +381.11.311.5251
www.elsys-design.com
