ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/platform/chrome/chromeos_tbmc.c b/marvell/linux/drivers/platform/chrome/chromeos_tbmc.c
new file mode 100644
index 0000000..d1cf8f3
--- /dev/null
+++ b/marvell/linux/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");