drivers: kscan: Introduce SDL mouse driver

Introduces a new SDL mouse driver for the keyboard scan (kscan)
interface. Driver is implemented as SDL event filter

Signed-off-by: Pavlo Hamov <pavlo_hamov@jabil.com>

boards/posix/native_posix/Kconfig.defconfig

@@ -69,6 +69,10 @@ config SDL_DISPLAY
 	default y
 	depends on DISPLAY
 
+config KSCAN_SDL
+	default y
+	depends on KSCAN
+
 config FLASH_SIMULATOR
 	default y
 	depends on FLASH

drivers/kscan/CMakeLists.txt

@@ -4,5 +4,6 @@ zephyr_library()
 
 zephyr_library_sources_ifdef(CONFIG_KSCAN_FT5336	kscan_ft5336.c)
 zephyr_library_sources_ifdef(CONFIG_KSCAN_XEC		kscan_mchp_xec.c)
+zephyr_library_sources_ifdef(CONFIG_KSCAN_SDL		kscan_sdl.c)
 
 zephyr_library_sources_ifdef(CONFIG_USERSPACE	    kscan_handlers.c)

drivers/kscan/Kconfig

@@ -12,6 +12,7 @@ if KSCAN
 
 source "drivers/kscan/Kconfig.ft5336"
 source "drivers/kscan/Kconfig.xec"
+source "drivers/kscan/Kconfig.sdl"
 
 module = KSCAN
 module-str = kscan

drivers/kscan/Kconfig.sdl

@@ -0,0 +1,14 @@
+# Copyright (c) 2020 Jabil Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+config KSCAN_SDL
+	bool "SDL event filter for touch panel emulation"
+	depends on HAS_SDL
+	help
+	  Enable driver for the SDL mouse event filter.
+
+config SDL_POINTER_KSCAN_DEV_NAME
+	string "SDL kscan device name"
+	depends on KSCAN_SDL
+	default LVGL_POINTER_KSCAN_DEV_NAME if LVGL
+	default "SDL_KSCAN"

drivers/kscan/kscan_sdl.c

@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2020 Jabil Inc.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <drivers/kscan.h>
+#include <logging/log.h>
+
+#include <SDL.h>
+
+LOG_MODULE_REGISTER(kscan, CONFIG_KSCAN_LOG_LEVEL);
+
+struct sdl_data {
+	kscan_callback_t callback;
+	bool enabled;
+};
+
+static int sdl_filter(void *arg, SDL_Event *event)
+{
+	struct device *dev = arg;
+	struct sdl_data *data = dev->driver_data;
+	u32_t row = 0;
+	u32_t column = 0;
+	bool pressed = 0;
+
+	switch (event->type) {
+	case SDL_MOUSEBUTTONDOWN: {
+		pressed = 1;
+		column = event->button.x;
+		row = event->button.y;
+	} break;
+	case SDL_MOUSEBUTTONUP: {
+		pressed = 0;
+		column = event->button.x;
+		row = event->button.y;
+	} break;
+	case SDL_MOUSEMOTION: {
+		if (!event->motion.state)
+			break;
+		pressed = 1;
+		column = event->button.x;
+		row = event->button.y;
+	} break;
+	default:
+		return 1;
+	}
+
+	if (data->enabled && data->callback) {
+		data->callback(dev, row, column, pressed);
+	}
+	return 1;
+}
+
+static int sdl_configure(struct device *dev, kscan_callback_t callback)
+{
+	struct sdl_data *data = dev->driver_data;
+
+	if (!callback) {
+		LOG_ERR("Callback is null");
+		return -EINVAL;
+	}
+	LOG_DBG("%s: set callback", dev->config->name);
+
+	data->callback = callback;
+
+	return 0;
+}
+
+static int sdl_enable_callback(struct device *dev)
+{
+	struct sdl_data *data = dev->driver_data;
+
+	LOG_DBG("%s: enable cb", dev->config->name);
+	data->enabled = true;
+	return 0;
+}
+
+static int sdl_disable_callback(struct device *dev)
+{
+	struct sdl_data *data = dev->driver_data;
+
+	LOG_DBG("%s: disable cb", dev->config->name);
+	data->enabled = false;
+	return 0;
+}
+
+static int sdl_init(struct device *dev)
+{
+	LOG_INF("Init '%s' device", dev->config->name);
+	SDL_AddEventWatch(sdl_filter, dev);
+
+	return 0;
+}
+
+
+static const struct kscan_driver_api sdl_driver_api = {
+	.config = sdl_configure,
+	.enable_callback = sdl_enable_callback,
+	.disable_callback = sdl_disable_callback,
+};
+
+static struct sdl_data sdl_data;
+
+DEVICE_AND_API_INIT(sdl, CONFIG_SDL_POINTER_KSCAN_DEV_NAME, sdl_init,
+		    &sdl_data, NULL,
+		    POST_KERNEL, CONFIG_KSCAN_INIT_PRIORITY,
+		    &sdl_driver_api);