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d7cc532df9
Currently, the onboard Cypress CYUSB3304 USB hub is not defined in
the device tree, and hub reset pin is provided as vcc5v0_host
regulator to usb phy. This causes instability issues, as a result
of improper reset duration.
The fixed regulator device requests the GPIO during probe in its
inactive state (except if regulator-boot-on property is set, in
which case it is requested in the active state). Considering gpio
is GPIO_ACTIVE_LOW for Puma, it means it’s driving it high. Then
the regulator gets enabled (because regulator-always-on property),
which drives it to its active state, meaning driving it low.
The Cypress CYUSB3304 USB hub actually requires the reset to be
asserted for at least 5 ms, which we cannot guarantee right now
since there's no delay in the current config, meaning the hub may
sometimes work or not. We could add delay as offered by
fixed-regulator but let's rather fix this by using the proper way
to model onboard USB hubs.
Define hub_2_0 and hub_3_0 nodes, as the onboard Cypress hub
consist of two 'logical' hubs, for USB2.0 and USB3.0.
Use the 'reset-gpios' property of hub to assign reset pin instead
of using regulator. Rename the vcc5v0_host regulator to
cy3304_reset to be more meaningful. Pin is configured to
output-high by default, which sets the hub in reset state
during pin controller initialization. This allows to avoid double
enumeration of devices in case the bootloader has setup the USB
hub before the kernel.
The vdd-supply and vdd2-supply properties in hub nodes are
added to provide correct dt-bindings, although power supplies are
always enabled based on HW design.
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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 reStructuredText 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.