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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/platform/chrome/chromeos_tbmc.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/platform/chrome/chromeos_tbmc.c')
-rw-r--r-- | drivers/platform/chrome/chromeos_tbmc.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/platform/chrome/chromeos_tbmc.c b/drivers/platform/chrome/chromeos_tbmc.c new file mode 100644 index 000000000..d1cf8f346 --- /dev/null +++ b/drivers/platform/chrome/chromeos_tbmc.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0 +// Driver to detect Tablet Mode for ChromeOS convertible. +// +// Copyright (C) 2017 Google, Inc. +// Author: Gwendal Grignou <gwendal@chromium.org> +// +// On Chromebook using ACPI, this device listens for notification +// from GOOG0006 and issue method TBMC to retrieve the status. +// +// GOOG0006 issues the notification when it receives EC_HOST_EVENT_MODE_CHANGE +// from the EC. +// Method TBMC reads EC_ACPI_MEM_DEVICE_ORIENTATION byte from the shared +// memory region. + +#include <linux/acpi.h> +#include <linux/input.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/printk.h> + +#define DRV_NAME "chromeos_tbmc" +#define ACPI_DRV_NAME "GOOG0006" + +static int chromeos_tbmc_query_switch(struct acpi_device *adev, + struct input_dev *idev) +{ + unsigned long long state; + acpi_status status; + + status = acpi_evaluate_integer(adev->handle, "TBMC", NULL, &state); + if (ACPI_FAILURE(status)) + return -ENODEV; + + /* input layer checks if event is redundant */ + input_report_switch(idev, SW_TABLET_MODE, state); + input_sync(idev); + + return 0; +} + +static __maybe_unused int chromeos_tbmc_resume(struct device *dev) +{ + struct acpi_device *adev = to_acpi_device(dev); + + return chromeos_tbmc_query_switch(adev, adev->driver_data); +} + +static void chromeos_tbmc_notify(struct acpi_device *adev, u32 event) +{ + acpi_pm_wakeup_event(&adev->dev); + switch (event) { + case 0x80: + chromeos_tbmc_query_switch(adev, adev->driver_data); + break; + default: + dev_err(&adev->dev, "Unexpected event: 0x%08X\n", event); + } +} + +static int chromeos_tbmc_open(struct input_dev *idev) +{ + struct acpi_device *adev = input_get_drvdata(idev); + + return chromeos_tbmc_query_switch(adev, idev); +} + +static int chromeos_tbmc_add(struct acpi_device *adev) +{ + struct input_dev *idev; + struct device *dev = &adev->dev; + int ret; + + idev = devm_input_allocate_device(dev); + if (!idev) + return -ENOMEM; + + idev->name = "Tablet Mode Switch"; + idev->phys = acpi_device_hid(adev); + + idev->id.bustype = BUS_HOST; + idev->id.version = 1; + idev->id.product = 0; + idev->open = chromeos_tbmc_open; + + input_set_drvdata(idev, adev); + adev->driver_data = idev; + + input_set_capability(idev, EV_SW, SW_TABLET_MODE); + ret = input_register_device(idev); + if (ret) { + dev_err(dev, "cannot register input device\n"); + return ret; + } + device_init_wakeup(dev, true); + return 0; +} + +static const struct acpi_device_id chromeos_tbmc_acpi_device_ids[] = { + { ACPI_DRV_NAME, 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, chromeos_tbmc_acpi_device_ids); + +static SIMPLE_DEV_PM_OPS(chromeos_tbmc_pm_ops, NULL, + chromeos_tbmc_resume); + +static struct acpi_driver chromeos_tbmc_driver = { + .name = DRV_NAME, + .class = DRV_NAME, + .ids = chromeos_tbmc_acpi_device_ids, + .ops = { + .add = chromeos_tbmc_add, + .notify = chromeos_tbmc_notify, + }, + .drv.pm = &chromeos_tbmc_pm_ops, +}; + +module_acpi_driver(chromeos_tbmc_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("ChromeOS ACPI tablet switch driver"); |