[U-Boot] [PATCH 0/7] tegra: Enhance funcmux to support I2C and MMC

Stephen Warren swarren at nvidia.com
Tue Jan 10 00:11:37 CET 2012


On 01/09/2012 03:53 PM, Simon Glass wrote:
> This series expands funcmux_select() to support configs other than 0, and
> to support options associated with a config.
> 
> This permits introduction of I2C support using multiple config options.
> 
> The options parameter is used by MMC to select standard (4-bit) or 8-bit
> operation.

The unification in this series basically seems fine.

Why not consider bus width part of the "config" though, rather the
complicating things with an extra parameter? As an example, for SDMMC4,
you'd have say:

0: ATC + ATD 8 bit
1: ATB + GMA 4 bit
2: ATB + GMA + GME 8 bit

... and no option values.

Also, we should probably define names for the config values, at least in
the cases where 0 isn't the only option. Hard-coding 0 or 1 at the call
sites isn't very meaningful.

Oh, and SDMMC4's option 0 isn't correct: I think pin group ATB should be
removed, since it contains signals SDIO4_CLK and SDIO4_CMD which are
also part of pin group ATC, when those pin groups are set to function
SDIO4 at least. I didn't check to see if any other similar problems exist.

-- 
nvpublic


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