RFC: what do we do with system controllers?

On Wed, Feb 29, 2012 at 10:59:23AM +0100, Linus Walleij wrote:

On Tue, Feb 28, 2012 at 9:38 AM, Russell King - ARM Linux
[off-list ref] wrote:

quoted

On Tue, Feb 28, 2012 at 06:48:12AM +0100, Linus Walleij wrote:

quoted

Mainly addressed to Greg but anyone is welcome to join the
discussion...

Several ARM platforms have system controllers. In this I
include all custom terminology such as:

- System Control
- Chip Controller
- Core Module control registers
- Power Reset Control Management Units
- Multimedia Communications Port

Why do you include this? ?If you include this, you should include things
like SSP/SPI ports, I2C and other such buses.

Mainly because it has these specific MCP controller oddity
functions:

mcp_set_telecom_divisor()
mcp_set_audio_divisor()

i.e. it has some "strangeness" of system controller type
(telecom? que?) But it's quite little and no big deal, drop
it off the list.

MCP = Multimedia Communication Port.  It is designed to work with the
UCB1200 and UCB1300 codec devices, which have two parts to them: a
telecom / pots interface and an audio interface.

The host side needs to be programmed with the appropriate sample rate -
it's the host side which controls the sample rate not the codec.