[PATCH 00/10] samsung: e850-96: Enable USB host and Ethernet

[Sam Protsenko]

On Sun, Aug 24, 2025 at 8:22 AM Anand Moon <linux.amoon at gmail.com> wrote:
>
> Hi Sam
>

Hi Anand,

> On Thu, 7 Aug 2025 at 03:57, Sam Protsenko <semen.protsenko at linaro.org> wrote:
> >
> > The E850-96 board has a LAN9514 chip which acts as a USB hub and
> > Ethernet controller. It's connected to the SoC via USB lines. In order
> > to make this chip functional the USB controller in Exynos850 SoC has to
> > be configured in the host role, and the corresponding power regulator
> > has to be enabled as well.
> >
> > This patch series enables USB host and network support on the E850-96 by
> > making use of the LAN9514 chip. While at it, enable all power regulators
> > (LDO) in the PMIC chip which can be useful in the bootloader and kernel,
> > including the regulator used for LAN9514.
> >
> > Sam Protsenko (10):
> >   usb: host: dwc3-of-simple: Add exynos850 compatible
> >   board: samsung: e850-96: Set ethaddr
> >   board: samsung: e850-96: Add ACPM code
> >   board: samsung: e850-96: Add PMIC code
> >   board: samsung: e850-96: Configure PMIC regulators
> >   board: samsung: e850-96: Extract device info from fw loading code
> >   board: samsung: e850-96: Add bootdev var to choose boot device
> >   configs: e850-96: Disable CONFIG_DEFAULT_FDT_FILE
> >   configs: e850-96: Enable USB host support
> >   configs: e850-96: Enable Ethernet
> >
> >  board/samsung/e850-96/Makefile    |   2 +-
> >  board/samsung/e850-96/acpm.c      | 169 ++++++++++++++++++++++++++++++
> >  board/samsung/e850-96/acpm.h      |  27 +++++
> >  board/samsung/e850-96/e850-96.c   |  97 +++++++++++++++--
> >  board/samsung/e850-96/e850-96.env |   2 +-
> >  board/samsung/e850-96/fw.c        |  45 ++++----
> >  board/samsung/e850-96/fw.h        |   4 +-
> >  board/samsung/e850-96/pmic.c      | 144 +++++++++++++++++++++++++
> >  board/samsung/e850-96/pmic.h      |  14 +++
> >  configs/e850-96_defconfig         |  10 +-
> >  drivers/usb/host/dwc3-of-simple.c |   1 +
> >  11 files changed, 482 insertions(+), 33 deletions(-)
> >  create mode 100644 board/samsung/e850-96/acpm.c
> >  create mode 100644 board/samsung/e850-96/acpm.h
> >  create mode 100644 board/samsung/e850-96/pmic.c
> >  create mode 100644 board/samsung/e850-96/pmic.h
> >
> Can you move pmic to drivers/power/pmic/ ?
>

Thank you for the review! This PMIC code is not really a driver, at
least not yet. It's an ad-hoc solution, which is very specific to
E850-96 board, and in its current form can't be used (even in theory)
for different platforms. It also doesn't conform to U-Boot's Driver
Model -- and I'd like to avoid reworking in such a way, please see the
explanation below. At the moment it's very minimal and only needed to
make Ethernet functional.

The plan for proper PMIC enablement is to do that first in Linux kernel, i.e.:
  - implement S2MPU12 driver
  - define ACPM bus in device tree
  - define PMIC node in device tree and describe all needed LDO regulators

and then porting all that into U-Boot. But that effort might take
quite a long time to implement, as I'm the only engineer working on
the E850-96 enablement at the moment. So I really think it's better to
keep the PMIC code as a part of the board code for now, hope you're ok
with that?

Thanks!

> Thanks
> -Anand