5741022cbd
Bay Trail / BYT SoCs do not have a builtin device-mode phy, instead they require an external ULPI phy for device-mode. Only some BYT devices have an external phy, but even on those devices device-mode is not working because the dwc3 does not see the phy. The problem is that the ACPI fwnode for the dwc3 does not contain the expected GPIO resources for the GPIOs connected to the chip-select and reset pins of the phy. I've found the workaround which some Android x86 kernels use for this: https://github.com/BORETS24/Kernel-for-Asus-Zenfone-2/blob/master/arch/x86/platform/intel-mid/device_libs/pci/platform_usb_otg.c Which boils down to hardcoding the GPIOs for these devices. The good news it that all boards (*) use the same GPIOs. This commit fixes the ULPI phy not woring by adding a gpiod_lookup_table call which adds a hardcoded mapping for BYT devices. Note that the mapping added by gpiod_add_lookup_table is a fallback mapping, so boards which properly provide GPIO resources in the ACPI firmware-node resources will not use this. *) Except for the first revision of the evalulation-kit, which normal users don't have Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> |
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| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
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| samples | ||
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| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
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| README | ||
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 Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
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.