58577966a4
Currently the DT for QCS404 SoC has setup for 2 USB2 PHYs with one each
assigned to USB3 controller and USB2 controller. This assignment is
incorrect which only works by luck: as when each USB HCI comes up it
configures the *other* controllers PHY which is enough to make them
happy. If, for any reason, we were to disable one of the controllers then
both would stop working.
This was a difficult inconsistency to be caught which was found while
trying to enable USB support in u-boot. So with all the required drivers
ported to u-boot, I couldn't get the same USB storage device enumerated
in u-boot which was being enumerated fine by the kernel.
The root cause of the problem came out to be that I wasn't enabling USB2
PHY: "usb2_phy_prim" in u-boot. Then I realised that via simply disabling
the same USB2 PHY currently assigned to USB2 host controller in the
kernel disabled enumeration for USB3 host controller as well.
So fix this inconsistency by correctly assigning USB2 PHYs.
Fixes: 9375e7d719b3 ("arm64: dts: qcom: qcs404: Add USB devices and PHYs")
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220711083038.1518529-1-sumit.garg@linaro.org
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.