Re: [PATCH 1/4] ARM: dts: sunxi: Add regulator-boot-on to usb host port regulator nodes

On Mon, Jun 22, 2015 at 10:28:16AM +0200, Hans de Goede wrote:

Hi,

On 22-06-15 02:30, Julian Calaby wrote:

quoted

Hi Hans,

On Sun, Jun 21, 2015 at 1:40 AM, Hans de Goede [off-list ref] wrote:

quoted

u-boot will have turned on the power to the usb host ports, so mark them
as regulator-boot-on, this stops the power on the ports from temporarily
getting turned off during boot, causing issues with e.g. usb powered
harddisks.

Stupid question: shouldn't u-boot set this property?

We could make u-boot set this property but that will require a lot of code on
u-boot's side which is simply not there atm. And traditionally this property
is is simply a part of the dts files as shipped with the kernel.

What happens if the property is set but the regulator is not actually
enabled?

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com