[PATCH master] ARM: i.MX8M: nxp-imx8mn-evk: use regular i2c read for device detection

[Sascha Hauer]

On Sat, Oct 30, 2021 at 04:19:34PM +0200, Ahmad Fatoum wrote:
> The barebox-nxp-imx8mn-evk image supports both DDR4 and LPDDR4 variants
> by probing for the PMIC in use as the former uses a BD71847 and the
> latter a PCA9450B.
> 
> The PCA9450B was observed to hang on the 0-byte (probe) reads.
> This results in I/O errors during later PMIC writes and the image
> would only boot on the EVKs with DDR4, which have the other PMIC.
> 
> Fix this by switching to a 1 byte read instead. Change tested on
> i.MX8MN DDR4 EVK as well as another board with LPDDR4.
> 
> While at it, note the address of the PMIC in the error message, so it's
> clear, what the result of the i2c probe was.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
> ---
>  arch/arm/boards/nxp-imx8mn-evk/lowlevel.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)

Applied, thanks

Sascha


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