> From: Stephen Warren <[email protected]>
> To: [email protected], Heiko Schocher <[email protected]>, 
> Cc: Stephen Warren <[email protected]>, Tom Warren <[email protected]>
> Date: 2014/06/25 19:05
> Subject: [U-Boot] [PATCH 1/3] i2c: tegra: use repeated start for reads
> Sent by: [email protected]
> 
> From: Stephen Warren <[email protected]>
> 
> I2C read transactions are typically implemented as follows:
> 
> START(write) address REPEATED_START(read) data... STOP
> 
> However, Tegra's I2C driver currently implements reads as follows:
> 
> START(write) address STOP START(read) data... STOP
> 
> This sequence confuses at least the AS3722 PMIC on the Jetson TK1 board,
> leading to corrupted read data in some cases. Fix the driver to chain
> the transactions together using repeated starts to solve this.

While I agree to use Repeated START I just wanted to share this:
A common reason for STOP START(read) sequence not working sometimes is 
that
the driver initializes STOP but does not wait for the STOP to complete
before issuing a START.

 Jocke 
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