dm: Add a demonstration/example driver

As an example of how to write a uclass and a driver, provide a demo version
of each, accessible through the 'demo' command.

To use these with driver model, define CONFIG_CMD_DEMO and CONFIG_DM_DEMO.

The two demo drivers are enabled with CONFIG_DM_DEMO_SIMPLE and
CONFIG_DM_DEMO_SHAPE.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Pavel Herrmann <morpheus.ibis@gmail.com>
Signed-off-by: Viktor Křivák <viktor.krivak@gmail.com>
Signed-off-by: Tomas Hlavacek <tmshlvck@gmail.com>

1 files changed, 127 insertions, 0 deletions

diff --git a/drivers/demo/demo-shape.c b/drivers/demo/demo-shape.c
new file mode 100644
index 0000000..2f0eb96
--- /dev/null
+++ b/drivers/demo/demo-shape.c
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2013 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <malloc.h>
+#include <dm-demo.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Shape size */
+#define WIDTH	8
+#define HEIGHT	6
+
+struct shape_data {
+	int num_chars;	/* Number of non-space characters output so far */
+};
+
+/* Crazy little function to draw shapes on the console */
+static int shape_hello(struct device *dev, int ch)
+{
+	const struct dm_demo_pdata *pdata = dev_get_platdata(dev);
+	struct shape_data *data = dev_get_priv(dev);
+	static const struct shape {
+		int start;
+		int end;
+		int dstart;
+		int dend;
+	} shapes[3] = {
+		{ 0, 1, 0, 1 },
+		{ 0, WIDTH, 0, 0 },
+		{ HEIGHT / 2 - 1, WIDTH - HEIGHT / 2 + 1, -1, 1},
+	};
+	struct shape shape;
+	unsigned int index;
+	int line, pos, inside;
+	const char *colour = pdata->colour;
+	int first = 0;
+
+	if (!ch)
+		ch = pdata->default_char;
+	if (!ch)
+		ch = '@';
+
+	index = (pdata->sides / 2) - 1;
+	if (index >= ARRAY_SIZE(shapes))
+		return -EIO;
+	shape = shapes[index];
+
+	for (line = 0; line < HEIGHT; line++) {
+		first = 1;
+		for (pos = 0; pos < WIDTH; pos++) {
+			inside = pos >= shape.start && pos < shape.end;
+			if (inside) {
+				putc(first ? *colour++ : ch);
+				data->num_chars++;
+				first = 0;
+				if (!*colour)
+					colour = pdata->colour;
+			} else {
+				putc(' ');
+			}
+		}
+		putc('\n');
+		shape.start += shape.dstart;
+		shape.end += shape.dend;
+		if (shape.start < 0) {
+			shape.dstart = -shape.dstart;
+			shape.dend = -shape.dend;
+			shape.start += shape.dstart;
+			shape.end += shape.dend;
+		}
+	}
+
+	return 0;
+}
+
+static int shape_status(struct device *dev, int *status)
+{
+	struct shape_data *data = dev_get_priv(dev);
+
+	*status = data->num_chars;
+	return 0;
+}
+
+static const struct demo_ops shape_ops = {
+	.hello = shape_hello,
+	.status = shape_status,
+};
+
+static int shape_ofdata_to_platdata(struct device *dev)
+{
+	struct dm_demo_pdata *pdata = dev_get_platdata(dev);
+	int ret;
+
+	/* Parse the data that is common with all demo devices */
+	ret = demo_parse_dt(dev);
+	if (ret)
+		return ret;
+
+	/* Parse the data that only we need */
+	pdata->default_char = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+					     "character", '@');
+
+	return 0;
+}
+
+static const struct device_id demo_shape_id[] = {
+	{ "demo-shape", 0 },
+	{ },
+};
+
+U_BOOT_DRIVER(demo_shape_drv) = {
+	.name	= "demo_shape_drv",
+	.of_match = demo_shape_id,
+	.id	= UCLASS_DEMO,
+	.ofdata_to_platdata = shape_ofdata_to_platdata,
+	.ops	= &shape_ops,
+	.priv_auto_alloc_size = sizeof(struct shape_data),
+	.platdata_auto_alloc_size = sizeof(struct dm_demo_pdata),
+};