mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-06 02:50:49 +09:00
a7efc2b035
[ Upstream commit 7d62beb102d6fa9a4e5e874be7fbf47a62fcc4f6 ] Dell systems utilize an EC-based touchpad emulation when the ACPI touchpad _DSM is not invoked. This emulation acts as a secondary master on the I2C bus, designed for scenarios where the I2C touchpad driver is absent, such as in BIOS menus. Typically, loading the i2c-hid module triggers the _DSM at initialization, disabling the EC-based emulation. However, if the i2c-hid module is missing from the boot kernel used for hibernation snapshot restoration, the _DSM remains uncalled, resulting in dual masters on the I2C bus and subsequent arbitration errors. This issue arises when i2c-hid resides in the rootfs instead of the kernel or initramfs. To address this, switch from using the SYSTEM_SLEEP_PM_OPS() macro to dedicated callbacks, introducing a specific callback for restoring the S4 image. This callback ensures the _DSM is invoked. Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org> Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.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.