[U-Boot] [PATCH 3/3] mpc5200: make i2c faster

Wolfgang Denk wd at denx.de
Sat Mar 21 20:48:53 CET 2009


Dear Jon,

In message <20090321133848.11905.59350.stgit at localhost> you wrote:
> From: Sascha Hauer <s.hauer at pengutronix.de>
> 
> The mpc5xxx i2c driver has great delays while waiting for the chip status.
> make the delays smaller and the driver faster.
> 
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  cpu/mpc5xxx/i2c.c |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)

Are you absolutely sure that reducing these delays from 1 millisecond
to 1 microsecond will work on all boards with all currently supported
devices?

And how much do we make I2C faster this way? Where do we save time,
and how much?

Best regards,

Wolfgang Denk

-- 
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