3 files changed, 271 insertions, 0 deletions
diff --git a/samples/auxdisplay/.gitignore b/samples/auxdisplay/.gitignore
new file mode 100644
index 000000000..d02381684
--- /dev/null
+++ b/samples/auxdisplay/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+/cfag12864b-example
diff --git a/samples/auxdisplay/Makefile b/samples/auxdisplay/Makefile
new file mode 100644
index 000000000..19d556893
--- /dev/null
+++ b/samples/auxdisplay/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+userprogs-always-y += cfag12864b-example
diff --git a/samples/auxdisplay/cfag12864b-example.c b/samples/auxdisplay/cfag12864b-example.c
new file mode 100644
index 000000000..2e3bb7375
--- /dev/null
+++ b/samples/auxdisplay/cfag12864b-example.c
@@ -0,0 +1,267 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *    Filename: cfag12864b-example.c
+ *     Version: 0.1.0
+ * Description: cfag12864b LCD userspace example program
+ *
+ *      Author: Copyright (C) Miguel Ojeda <ojeda@kernel.org>
+ *        Date: 2006-10-31
+ */
+
+/*
+ * ------------------------
+ * start of cfag12864b code
+ * ------------------------
+ */
+
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#define CFAG12864B_WIDTH		(128)
+#define CFAG12864B_HEIGHT		(64)
+#define CFAG12864B_SIZE			(128 * 64 / 8)
+#define CFAG12864B_BPB			(8)
+#define CFAG12864B_ADDRESS(x, y)	((y) * CFAG12864B_WIDTH / \
+					CFAG12864B_BPB + (x) / CFAG12864B_BPB)
+#define CFAG12864B_BIT(n)		(((unsigned char) 1) << (n))
+
+#undef CFAG12864B_DOCHECK
+#ifdef CFAG12864B_DOCHECK
+	#define CFAG12864B_CHECK(x, y)		((x) < CFAG12864B_WIDTH && \
+						(y) < CFAG12864B_HEIGHT)
+#else
+	#define CFAG12864B_CHECK(x, y)		(1)
+#endif
+
+int cfag12864b_fd;
+unsigned char * cfag12864b_mem;
+unsigned char cfag12864b_buffer[CFAG12864B_SIZE];
+
+/*
+ * init a cfag12864b framebuffer device
+ *
+ * No error:       return = 0
+ * Unable to open: return = -1
+ * Unable to mmap: return = -2
+ */
+static int cfag12864b_init(char *path)
+{
+	cfag12864b_fd = open(path, O_RDWR);
+	if (cfag12864b_fd == -1)
+		return -1;
+
+	cfag12864b_mem = mmap(0, CFAG12864B_SIZE, PROT_READ | PROT_WRITE,
+		MAP_SHARED, cfag12864b_fd, 0);
+	if (cfag12864b_mem == MAP_FAILED) {
+		close(cfag12864b_fd);
+		return -2;
+	}
+
+	return 0;
+}
+
+/*
+ * exit a cfag12864b framebuffer device
+ */
+static void cfag12864b_exit(void)
+{
+	munmap(cfag12864b_mem, CFAG12864B_SIZE);
+	close(cfag12864b_fd);
+}
+
+/*
+ * set (x, y) pixel
+ */
+static void cfag12864b_set(unsigned char x, unsigned char y)
+{
+	if (CFAG12864B_CHECK(x, y))
+		cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] |=
+			CFAG12864B_BIT(x % CFAG12864B_BPB);
+}
+
+/*
+ * unset (x, y) pixel
+ */
+static void cfag12864b_unset(unsigned char x, unsigned char y)
+{
+	if (CFAG12864B_CHECK(x, y))
+		cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &=
+			~CFAG12864B_BIT(x % CFAG12864B_BPB);
+}
+
+/*
+ * is set (x, y) pixel?
+ *
+ * Pixel off: return = 0
+ * Pixel on:  return = 1
+ */
+static unsigned char cfag12864b_isset(unsigned char x, unsigned char y)
+{
+	if (CFAG12864B_CHECK(x, y))
+		if (cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &
+			CFAG12864B_BIT(x % CFAG12864B_BPB))
+			return 1;
+
+	return 0;
+}
+
+/*
+ * not (x, y) pixel
+ */
+static void cfag12864b_not(unsigned char x, unsigned char y)
+{
+	if (cfag12864b_isset(x, y))
+		cfag12864b_unset(x, y);
+	else
+		cfag12864b_set(x, y);
+}
+
+/*
+ * fill (set all pixels)
+ */
+static void cfag12864b_fill(void)
+{
+	unsigned short i;
+
+	for (i = 0; i < CFAG12864B_SIZE; i++)
+		cfag12864b_buffer[i] = 0xFF;
+}
+
+/*
+ * clear (unset all pixels)
+ */
+static void cfag12864b_clear(void)
+{
+	unsigned short i;
+
+	for (i = 0; i < CFAG12864B_SIZE; i++)
+		cfag12864b_buffer[i] = 0;
+}
+
+/*
+ * format a [128*64] matrix
+ *
+ * Pixel off: src[i] = 0
+ * Pixel on:  src[i] > 0
+ */
+static void cfag12864b_format(unsigned char * matrix)
+{
+	unsigned char i, j, n;
+
+	for (i = 0; i < CFAG12864B_HEIGHT; i++)
+	for (j = 0; j < CFAG12864B_WIDTH / CFAG12864B_BPB; j++) {
+		cfag12864b_buffer[i * CFAG12864B_WIDTH / CFAG12864B_BPB +
+			j] = 0;
+		for (n = 0; n < CFAG12864B_BPB; n++)
+			if (matrix[i * CFAG12864B_WIDTH +
+				j * CFAG12864B_BPB + n])
+				cfag12864b_buffer[i * CFAG12864B_WIDTH /
+					CFAG12864B_BPB + j] |=
+					CFAG12864B_BIT(n);
+	}
+}
+
+/*
+ * blit buffer to lcd
+ */
+static void cfag12864b_blit(void)
+{
+	memcpy(cfag12864b_mem, cfag12864b_buffer, CFAG12864B_SIZE);
+}
+
+/*
+ * ----------------------
+ * end of cfag12864b code
+ * ----------------------
+ */
+
+#include <stdio.h>
+
+#define EXAMPLES	6
+
+static void example(unsigned char n)
+{
+	unsigned short i, j;
+	unsigned char matrix[CFAG12864B_WIDTH * CFAG12864B_HEIGHT];
+
+	if (n > EXAMPLES)
+		return;
+
+	printf("Example %i/%i - ", n, EXAMPLES);
+
+	switch (n) {
+	case 1:
+		printf("Draw points setting bits");
+		cfag12864b_clear();
+		for (i = 0; i < CFAG12864B_WIDTH; i += 2)
+			for (j = 0; j < CFAG12864B_HEIGHT; j += 2)
+				cfag12864b_set(i, j);
+		break;
+
+	case 2:
+		printf("Clear the LCD");
+		cfag12864b_clear();
+		break;
+
+	case 3:
+		printf("Draw rows formatting a [128*64] matrix");
+		memset(matrix, 0, CFAG12864B_WIDTH * CFAG12864B_HEIGHT);
+		for (i = 0; i < CFAG12864B_WIDTH; i++)
+			for (j = 0; j < CFAG12864B_HEIGHT; j += 2)
+				matrix[j * CFAG12864B_WIDTH + i] = 1;
+		cfag12864b_format(matrix);
+		break;
+
+	case 4:
+		printf("Fill the lcd");
+		cfag12864b_fill();
+		break;
+
+	case 5:
+		printf("Draw columns unsetting bits");
+		for (i = 0; i < CFAG12864B_WIDTH; i += 2)
+			for (j = 0; j < CFAG12864B_HEIGHT; j++)
+				cfag12864b_unset(i, j);
+		break;
+
+	case 6:
+		printf("Do negative not-ing all bits");
+		for (i = 0; i < CFAG12864B_WIDTH; i++)
+			for (j = 0; j < CFAG12864B_HEIGHT; j ++)
+				cfag12864b_not(i, j);
+		break;
+	}
+
+	puts(" - [Press Enter]");
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned char n;
+
+	if (argc != 2) {
+		printf(
+			"Syntax:  %s fbdev\n"
+			"Usually: /dev/fb0, /dev/fb1...\n", argv[0]);
+		return -1;
+	}
+
+	if (cfag12864b_init(argv[1])) {
+		printf("Can't init %s fbdev\n", argv[1]);
+		return -2;
+	}
+
+	for (n = 1; n <= EXAMPLES; n++) {
+		example(n);
+		cfag12864b_blit();
+		while (getchar() != '\n');
+	}
+
+	cfag12864b_exit();
+
+	return 0;
+}