drivers/i2c/wacom_ts: Add support for WCOM touchscreen device driver

BUG=chrome-os-partner:57846

Change-Id: Id6bd91b3fd6420994ad5811d362618b1a38a8afa
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/17092
Tested-by: build bot (Jenkins)
Reviewed-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>

src/drivers/i2c/wacom_ts/Kconfig

@@ -0,0 +1,3 @@
+config DRIVERS_I2C_WACOM_TS
+	bool
+	select DRIVERS_I2C_GENERIC

src/drivers/i2c/wacom_ts/Makefile.inc

@@ -0,0 +1 @@
+ramstage-$(CONFIG_DRIVERS_I2C_WACOM_TS) += ts.c

src/drivers/i2c/wacom_ts/chip.h

@@ -0,0 +1,30 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2016 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef __I2C_WACOM_TS_CHIP_H__
+#define __I2C_WACOM_TS_CHIP_H__
+
+#include <drivers/i2c/generic/chip.h>
+
+#define WCOM50C1_HID		"WCOM50C1"
+#define PNP0C50_CID		"PNP0C50"
+#define WCOM_TS_DESC		"WCOM Touchscreen"
+
+struct drivers_i2c_wacom_ts_config {
+	struct drivers_i2c_generic_config generic;
+	uint8_t hid_desc_reg_offset;
+};
+
+#endif /* __I2C_WACOM_TS_CHIP_H__ */

src/drivers/i2c/wacom_ts/ts.c

@@ -0,0 +1,59 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2016 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ */
+
+#include <arch/acpigen_dsm.h>
+#include <device/device.h>
+#include <stdint.h>
+#include "chip.h"
+
+static void i2c_wacom_ts_fill_dsm(struct device *dev)
+{
+	struct drivers_i2c_wacom_ts_config *config = dev->chip_info;
+	struct dsm_i2c_hid_config dsm_config = {
+		.hid_desc_reg_offset = config->hid_desc_reg_offset,
+	};
+
+	acpigen_write_dsm_i2c_hid(&dsm_config);
+}
+
+static void i2c_wacom_ts_fill_ssdt_generator(struct device *dev)
+{
+	i2c_generic_fill_ssdt(dev, &i2c_wacom_ts_fill_dsm);
+}
+
+static const char *i2c_wacom_ts_acpi_name(struct device *dev)
+{
+	return "WCTS";
+}
+
+static struct device_operations i2c_wacom_ts_ops = {
+	.read_resources		  = DEVICE_NOOP,
+	.set_resources		  = DEVICE_NOOP,
+	.enable_resources	  = DEVICE_NOOP,
+#if IS_ENABLED(CONFIG_HAVE_ACPI_TABLES)
+	.acpi_name		  = &i2c_wacom_ts_acpi_name,
+	.acpi_fill_ssdt_generator = &i2c_wacom_ts_fill_ssdt_generator,
+#endif
+};
+
+static void i2c_wacom_ts_enable(struct device *dev)
+{
+	dev->ops = &i2c_wacom_ts_ops;
+}
+
+struct chip_operations drivers_i2c_wacom_ts_ops = {
+	CHIP_NAME("Wacom Touchscreen Device")
+	.enable_dev = &i2c_wacom_ts_enable
+};