1 files changed, 103 insertions, 0 deletions
diff --git a/drivers/mfd/cros_ec_acpi_gpe.c b/drivers/mfd/cros_ec_acpi_gpe.c
new file mode 100644
index 000000000000..56d305dab2d4
--- /dev/null
+++ b/drivers/mfd/cros_ec_acpi_gpe.c
@@ -0,0 +1,103 @@
+/*
+ * ChromeOS EC multi-function device
+ *
+ * Copyright (C) 2017 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * The ChromeOS EC multi function device is used to mux all the requests
+ * to the EC device for its multiple features: keyboard controller,
+ * battery charging and regulator control, firmware update.
+ */
+#include <linux/acpi.h>
+
+#define ACPI_LID_DEVICE      "LID0"
+
+static int ec_wake_gpe = -EINVAL;
+
+/*
+ * This handler indicates to ACPI core that this GPE should stay enabled for
+ * lid to work in suspend to idle path.
+ */
+static u32 cros_ec_gpe_handler(acpi_handle gpe_device, u32 gpe_number,
+			       void *data)
+{
+	return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
+}
+
+/*
+ * Get ACPI GPE for LID0 device.
+ */
+static int cros_ec_get_ec_wake_gpe(struct device *dev)
+{
+	struct acpi_device *cros_acpi_dev;
+	struct acpi_device *adev;
+	acpi_handle handle;
+	acpi_status status;
+	int ret;
+
+	cros_acpi_dev = ACPI_COMPANION(dev);
+
+	if (!cros_acpi_dev || !cros_acpi_dev->parent ||
+	   !cros_acpi_dev->parent->handle)
+		return -EINVAL;
+
+	status = acpi_get_handle(cros_acpi_dev->parent->handle, ACPI_LID_DEVICE,
+				 &handle);
+	if (ACPI_FAILURE(status))
+		return -EINVAL;
+
+	ret = acpi_bus_get_device(handle, &adev);
+	if (ret)
+		return ret;
+
+	return adev->wakeup.gpe_number;
+}
+
+int cros_ec_acpi_install_gpe_handler(struct device *dev)
+{
+	acpi_status status;
+
+	ec_wake_gpe = cros_ec_get_ec_wake_gpe(dev);
+
+	if (ec_wake_gpe < 0)
+		return ec_wake_gpe;
+
+	status = acpi_install_gpe_handler(NULL, ec_wake_gpe,
+					  ACPI_GPE_EDGE_TRIGGERED,
+					  &cros_ec_gpe_handler, NULL);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	dev_info(dev, "Initialized, GPE = 0x%x\n", ec_wake_gpe);
+
+	return 0;
+}
+
+void cros_ec_acpi_remove_gpe_handler(void)
+{
+	acpi_status status;
+
+	if (ec_wake_gpe < 0)
+		return;
+
+	status = acpi_remove_gpe_handler(NULL, ec_wake_gpe,
+						 &cros_ec_gpe_handler);
+	if (ACPI_FAILURE(status))
+		pr_err("failed to remove gpe handler\n");
+}
+
+void cros_ec_acpi_clear_gpe(void)
+{
+	if (ec_wake_gpe < 0)
+		return;
+
+	acpi_clear_gpe(NULL, ec_wake_gpe);
+}