[U-Boot] [PATCH v3 1/9] Revert "pico-imx7d: Add LCD support"

[Jun Nie]

Fabio Estevam <festevam at gmail.com> 于2019年4月25日周四 上午11:28写道：
>
> Hi Jun,
>
> On Wed, Apr 24, 2019 at 11:53 PM Jun Nie <jun.nie at linaro.org> wrote:
>
> > It blocks boot up with default defconfig. I see it is suggested to be
> > reverted in mailist weeks ago. I thought you guys knew about it.
>
> Please keep in mind that the rationale of a patch must always be provided.
>
> In this case the issue is related to the limit of the current that the
> host PC USB port can provide.

Thank you very much for this info! I did not noticed this patch yet.
So power supply should be changed or disable LCD as a workaround
locally.

Jun

>
> Please see the following commit for detaisl:
>
> commit 00102ae52055e294ac37ae1380f37620f4a8bb26
> Author: Fabio Estevam <festevam at gmail.com>
> Date:   Wed Mar 27 20:03:39 2019 -0300
>
>     pico-imx7d: README: Recommend the usage of a USB hub
>
>     Since commit 9e3c0174da842 ("pico-imx7d: Add LCD support") we started to
>     notice some hangs in U-Boot.
>
>     There is not an issue on such commit per se, but due to the LCD support
>     the current drawn is increased and this may cause issues when powering
>     pico-imx7d-pi from USB.
>
>     Some computers may be a bit strict with USB current draw and will
>     shut down their ports if the draw is too high.
>
>     The solution for that is to use an externally powered USB hub between the
>     board and the host computer.
>
>     Add such recommendation to the README file.
>
>     Signed-off-by: Fabio Estevam <festevam at gmail.com>