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path: root/drivers/platform/surface/surface_dtx.c
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2022-07-02platform/surface: Update copyright year of various driversMaximilian Luz1-1/+1
Update the copyright of various Surface drivers to the current year. Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/20220624205800.1355621-4-luzmaximilian@gmail.com Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-06-04platform/surface: dtx: Add missing mutex_destroy() call in failure pathMaximilian Luz1-0/+1
When we fail to open the device file due to DTX being shut down, the mutex is initialized but never destroyed. We are destroying it when releasing the file, so add the missing call in the failure path as well. Fixes: 1d609992832e ("platform/surface: Add DTX driver") Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/20210604132540.533036-1-luzmaximilian@gmail.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-05-19platform/surface: dtx: Fix poll functionMaximilian Luz1-7/+1
The poll function should not return -ERESTARTSYS. Furthermore, locking in this function is completely unnecessary. The ddev->lock protects access to the main device and controller (ddev->dev and ddev->ctrl), ensuring that both are and remain valid while being accessed by clients. Both are, however, never accessed in the poll function. The shutdown test (via atomic bit flags) be safely done without locking, so drop locking here entirely. Reported-by: kernel test robot <lkp@intel.com> Fixes: 1d609992832e ("platform/surface: Add DTX driver) Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/20210513134437.2431022-1-luzmaximilian@gmail.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-04-07platform/surface: clean up a variable in surface_dtx_read()Dan Carpenter1-1/+1
The "&client->ddev->lock" and "&ddev->lock" are the same thing. Let's use "&ddev->lock" consistently. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/YF3TgCcpcCYl3a//@mwanda Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-03-23platform/surface: fix semicolon.cocci warningskernel test robot1-1/+1
drivers/platform/surface/surface_dtx.c:651:2-3: Unneeded semicolon Remove unneeded semicolon. Generated by: scripts/coccinelle/misc/semicolon.cocci Fixes: 1d609992832e ("platform/surface: Add DTX driver") CC: Maximilian Luz <luzmaximilian@gmail.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: kernel test robot <lkp@intel.com> Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/20210319051919.GA39801@ae4f36e4f012 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-03-17platform/surface: dtx: Add support for native SSAM devicesMaximilian Luz1-1/+89
Add support for native SSAM devices to the DTX driver. This allows support for the Surface Book 3, on which the DTX device is not present in ACPI. Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/20210308184819.437438-3-luzmaximilian@gmail.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2021-03-17platform/surface: Add DTX driverMaximilian Luz1-0/+1201
The Microsoft Surface Book series devices consist of a so-called clipboard part (containing the CPU, touchscreen, and primary battery) and a base part (containing keyboard, secondary battery, and optional discrete GPU). These parts can be separated, i.e. the clipboard can be detached and used as tablet. This detachment process is initiated by pressing a button. On the Surface Book 2 and 3 (targeted with this commit), the Surface Aggregator Module (i.e. the embedded controller on those devices) attempts to send a notification to any listening client driver and waits for further instructions (i.e. whether the detachment process should continue or be aborted). If it does not receive a response in a certain time-frame, the detachment process (by default) continues and the clipboard can be physically separated. In other words, (by default and) without a driver, the detachment process takes about 10 seconds to complete. This commit introduces a driver for this detachment system (called DTX). This driver allows a user-space daemon to control and influence the detachment behavior. Specifically, it forwards any detachment requests to user-space, allows user-space to make such requests itself, and allows handling of those requests. Requests can be handled by either aborting, continuing/allowing, or delaying (i.e. resetting the timeout via a heartbeat commend). The user-space API is implemented via the /dev/surface/dtx miscdevice. In addition, user-space can change the default behavior on timeout from allowing detachment to disallowing it, which is useful if the (optional) discrete GPU is in use. Furthermore, this driver allows user-space to receive notifications about the state of the base, specifically when it is physically removed (as opposed to detachment requested), in what manner it is connected (i.e. in reverse-/tent-/studio- or laptop-mode), and what type of base is connected. Based on this information, the driver also provides a simple tablet-mode switch (aliasing all modes without keyboard access, i.e. tablet-mode and studio-mode to its reported tablet-mode). An implementation of such a user-space daemon, allowing configuration of detachment behavior via scripts (e.g. safely unmounting USB devices connected to the base before continuing) can be found at [1]. [1]: https://github.com/linux-surface/surface-dtx-daemon Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com> Link: https://lore.kernel.org/r/20210308184819.437438-2-luzmaximilian@gmail.com Signed-off-by: Hans de Goede <hdegoede@redhat.com>