sys: add interface for generic touch device

drivers/include/touch_dev.h

@@ -0,0 +1,122 @@
+/*
+ * Copyright (C) 2020 Inria
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    drivers_touch_dev Touch device generic API
+ * @ingroup     drivers_misc
+ * @brief       Define the generic API of a touch device
+ * @experimental This API is experimental and in an early state - expect
+ *               changes!
+ * @{
+ *
+ * @author      Alexandre Abadie <alexandre.abadie@inria.fr>
+ */
+
+#ifndef TOUCH_DEV_H
+#define TOUCH_DEV_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+/**
+ * @brief   Forward declaration for touch device struct
+ */
+typedef struct touch_dev touch_dev_t;
+
+/**
+ * @brief   Touch coordinates
+ */
+typedef struct {
+    uint16_t x;     /**< X coordinate */
+    uint16_t y;     /**< Y coordinate */
+} touch_t;
+
+/**
+ * @brief   Generic type for a touch driver
+ */
+typedef struct {
+
+    /**
+     * @brief   Get the height of the touch device
+     *
+     * @param[in] dev       Pointer to the touch device
+     *
+     * @return              Height in points
+     */
+    uint16_t (*height)(const touch_dev_t *dev);
+
+    /**
+     * @brief   Get the width of the touch device
+     *
+     * @param[in] dev       Pointer to the touch device
+     *
+     * @return              Width in points
+     */
+    uint16_t (*width)(const touch_dev_t *dev);
+
+    /**
+     * @brief   Get the current touches on the touch device
+     *
+     * If @p touches is NULL, this function only returns the number of touches.
+     *
+     * @param[in] dev       Pointer to the touch device
+     * @param[out] touches  The array of touches
+     * @param[in] len       The touches array len
+     * @return              number of touch positions, 0 means no touch
+     */
+    uint8_t (*touches)(const touch_dev_t *dev, touch_t *touches, size_t len);
+} touch_dev_driver_t;
+
+/**
+ * @brief   Generic type for a touch device
+ */
+struct touch_dev {
+    const touch_dev_driver_t *driver;    /**< Pointer to driver of the touch device */
+};
+
+/**
+ * @brief   Get the height of the touch device
+ *
+ * @param[in] dev       Pointer to the touch device
+ *
+ * @return              Height in points
+ */
+uint16_t touch_dev_height(const touch_dev_t *dev);
+
+/**
+ * @brief   Get the width of the touch device
+ *
+ * @param[in] dev       Pointer to the touch device
+ *
+ * @return              Width in points
+ */
+uint16_t touch_dev_width(const touch_dev_t *dev);
+
+/**
+ * @brief   Get the current touches on the touch device
+ *
+ * If @p touches is NULL, this function only returns the number of touches.
+ *
+ * @param[in] dev       Pointer to the touch device
+ * @param[out] touches  The array of touches
+ * @param[in] len       The touches array len
+ * @return              number of touch positions, 0 means no touch
+ */
+uint8_t touch_dev_touches(const touch_dev_t *dev, touch_t *touches, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* TOUCH_DEV_H */
+/** @} */

drivers/touch_dev/Makefile

@@ -0,0 +1 @@
+include $(RIOTBASE)/Makefile.base

drivers/touch_dev/touch_dev.c

@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2020 Inria
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     drivers_touch_dev
+ * @{
+ *
+ * @file
+ * @brief       Helper functions for generic API of touch device
+ *
+ * @author      Alexandre Abadie <alexandre.abadie@inria.fr>
+ *
+ * @}
+ */
+
+#include <assert.h>
+#include <stddef.h>
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include "touch_dev.h"
+
+uint16_t touch_dev_height(const touch_dev_t *dev)
+{
+    assert(dev);
+
+    return dev->driver->height(dev);
+}
+
+uint16_t touch_dev_width(const touch_dev_t *dev)
+{
+    assert(dev);
+
+    return dev->driver->width(dev);
+}
+
+uint8_t touch_dev_touches(const touch_dev_t *dev, touch_t *touches, size_t len)
+{
+    assert(dev);
+
+    return dev->driver->touches(dev, touches, len);
+}