touch: add qti dummy touch driver

Add support for dummy touchscreen driver to help boot up the HW
with operating systems requiring at least one input devices in
pre-silicon platforms.

Change-Id: I0bb5c5a3dd2a8d945c3b0ecee738652ec9d2b561
Signed-off-by: Jeykumar Sankaran <quic_jeykumar@quicinc.com>

Android.mk

@@ -57,4 +57,15 @@ LOCAL_MODULE_PATH         := $(KERNEL_MODULES_OUT)
 include $(DLKM_DIR)/Build_external_kernelmodule.mk
 ###########################################################
 
+###########################################################
+include $(CLEAR_VARS)
+LOCAL_SRC_FILES   := $(wildcard $(LOCAL_PATH)/**/*) $(wildcard $(LOCAL_PATH)/*)
+LOCAL_MODULE              := dummy_ts.ko
+LOCAL_MODULE_KBUILD_NAME  := dummy_ts.ko
+LOCAL_MODULE_TAGS         := optional
+#LOCAL_MODULE_DEBUG_ENABLE := true
+LOCAL_MODULE_PATH         := $(KERNEL_MODULES_OUT)
+include $(DLKM_DIR)/Build_external_kernelmodule.mk
+###########################################################
+
 endif # DLKM check

Kbuild

@@ -115,4 +115,10 @@ ifeq ($(CONFIG_TOUCHSCREEN_ATMEL_MXT), y)
 	obj-$(CONFIG_MSM_TOUCH) += atmel_mxt_ts.o
 endif
 
+ifeq ($(CONFIG_TOUCHSCREEN_DUMMY), y)
+	dummy_ts-y := ./dummy_touch/dummy_touch.o
+
+	obj-$(CONFIG_MSM_TOUCH) += dummy_ts.o
+endif
+
 CDEFINES += -DBUILD_TIMESTAMP=\"$(shell date -u +'%Y-%m-%dT%H:%M:%SZ')\"

config/gki_kalamatouch.conf

@@ -1,4 +1,5 @@
 export CONFIG_TOUCHSCREEN_NT36XXX_I2C=y
 export CONFIG_TOUCHSCREEN_GOODIX_BRL=y
 export CONFIG_TOUCHSCREEN_ATMEL_MXT=y
+export CONFIG_TOUCHSCREEN_DUMMY=y
 export CONFIG_MSM_TOUCH=m

dummy_touch/dummy_touch.c

@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/mod_devicetable.h>
+
+MODULE_DESCRIPTION("QTI dummy touchscreen driver");
+MODULE_LICENSE("GPL v2");
+
+#define DEVICE_COMPATIBLE "qti,dummy_ts"
+#define DRIVER_NAME "qti_dummy_ts"
+
+static int dummy_touch_probe(struct platform_device *device)
+{
+	struct input_dev *touch_dev = NULL;
+	int rc;
+
+	touch_dev = input_allocate_device();
+	if (!touch_dev) {
+		pr_err("%s: input device allocate failed\n", __func__);
+		return -ENOMEM;
+	}
+
+	touch_dev->name = "qti_dummy_ts";
+	touch_dev->id.bustype = BUS_VIRTUAL;
+	touch_dev->evbit[0] = BIT_MASK(EV_KEY);
+	touch_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0);
+	touch_dev->dev.parent = NULL;
+
+	rc = input_register_device(touch_dev);
+	if (rc) {
+		pr_err("%s: touch device register failed, rc = %d\n", __func__, rc);
+		input_free_device(touch_dev);
+		return rc;
+	}
+
+	pr_info("qti_dummy_ts device registered\n");
+
+	platform_set_drvdata(device, (void *)touch_dev);
+
+	return 0;
+}
+
+static int dummy_touch_remove(struct platform_device *device)
+{
+	struct input_dev *touch_dev = NULL;
+
+	touch_dev = (struct input_dev *)platform_get_drvdata(device);
+	if (touch_dev)
+		input_free_device(touch_dev);
+
+	return 0;
+}
+
+static const struct of_device_id  dummy_touch_id[] = {
+	{.compatible = DEVICE_COMPATIBLE},
+	{}
+};
+
+static struct platform_driver dummy_touch_driver = {
+
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table = dummy_touch_id,
+	},
+	.probe = dummy_touch_probe,
+	.remove = dummy_touch_remove,
+};
+
+static int __init dummy_touch_init(void)
+{
+	platform_driver_register(&dummy_touch_driver);
+
+	return 0;
+}
+
+static void __exit dummy_touch_exit(void)
+{
+	platform_driver_unregister(&dummy_touch_driver);
+}
+
+late_initcall(dummy_touch_init);
+module_exit(dummy_touch_exit);

touch_driver_board.mk

@@ -3,6 +3,7 @@ ifneq ($(TARGET_BOARD_AUTO),true)
 	ifeq ($(call is-board-platform-in-list,$(TARGET_BOARD_PLATFORM)),true)
 		BOARD_VENDOR_KERNEL_MODULES += $(KERNEL_MODULES_OUT)/nt36xxx-i2c.ko \
 			$(KERNEL_MODULES_OUT)/goodix_ts.ko \
-			$(KERNEL_MODULES_OUT)/atmel_mxt_ts.ko
+			$(KERNEL_MODULES_OUT)/atmel_mxt_ts.ko \
+			$(KERNEL_MODULES_OUT)/dummy_ts.ko
 	endif
 endif

touch_driver_product.mk

@@ -1,4 +1,5 @@
 
 PRODUCT_PACKAGES += $(KERNEL_MODULES_OUT)/nt36xxx-i2c.ko \
 	$(KERNEL_MODULES_OUT)/goodix_ts.ko \
-	$(KERNEL_MODULES_OUT)/atmel_mxt_ts.ko
+	$(KERNEL_MODULES_OUT)/atmel_mxt_ts.ko \
+	$(KERNEL_MODULES_OUT)/dummy_ts.ko