diff --git a/drm_iface.c b/drm_iface.c
index 8fa25fd..a276eee 100644
--- a/drm_iface.c
+++ b/drm_iface.c
@@ -268,10 +268,14 @@ static int sharp_memory_clip_mono_tagged(struct sharp_memory_panel* panel, size_
 	// End DMA area
 	drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
 
-	// Add indicators if in range
-	if ((clip->x1 < (fb->width - INDICATORS_WIDTH))
-	 && (clip->y1 < INDICATOR_HEIGHT)) {
-		draw_indicators(panel, buf, fb->width, clip);
+	// Add status indicators
+	if (g_param_indicators) {
+
+		// Only redraw indicators if the dirty region would overwrite them
+		if ((clip->x1 < (fb->width - INDICATORS_WIDTH))
+		 && (clip->y1 < INDICATOR_HEIGHT)) {
+			draw_indicators(panel, buf, fb->width, clip);
+		}
 	}
 
 	// Convert in-place from 8-bit grayscale to mono
diff --git a/ioctl_iface.c b/ioctl_iface.c
index 7d3b7e5..1e0d058 100644
--- a/ioctl_iface.c
+++ b/ioctl_iface.c
@@ -1,13 +1,105 @@
 #include <linux/types.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
 
+#include "params_iface.h"
+#include "drm_iface.h"
 #include "ioctl_iface.h"
 
+#define SHARP_IOC_MAGIC 0xd5
+#define SHARP_IOCTQ_SET_INVERT _IOW(SHARP_IOC_MAGIC, 1, uint32_t)
+#define SHARP_IOCTQ_SET_INDICATOR _IOW(SHARP_IOC_MAGIC, 2, uint32_t)
+#define SHARP_IOC_MAXNR 2
+
+static int ioctl_set_invert(unsigned long arg)
+{
+	params_set_mono_invert((int)arg);
+
+	return 0;
+}
+
+static int ioctl_set_indicator(unsigned long arg)
+{
+	uint8_t idx, ch;
+
+	idx = arg >> 8;
+	ch = arg & 0xff;
+
+	return drm_set_indicator(idx, ch);
+}
+
+static int sharp_open(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
+static int sharp_release(struct inode *inode, struct file *filp)
+{
+	return 0;
+}
+
+static long int sharp_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+
+	case SHARP_IOCTQ_SET_INVERT:
+		(void)ioctl_set_invert((int)arg);
+		return 0;
+
+	case SHARP_IOCTQ_SET_INDICATOR:
+		(void)ioctl_set_indicator((int)arg);
+		return 0;
+
+
+	default: 
+		printk(KERN_INFO "Bad command: %d", cmd);
+		return -EINVAL;
+	}
+}
+
+static struct file_operations fops = {
+	.owner = THIS_MODULE,
+	.open = sharp_open,
+	.unlocked_ioctl = sharp_ioctl,
+	.release = sharp_release,
+};
+
+static struct cdev g_cdev;
+static dev_t g_dev;
+struct class *g_class;
+
 int ioctl_probe(void)
 {
+	int rc;
+
+	if ((rc = alloc_chrdev_region(&g_dev, 0, 1, "sharp"))) {
+		printk(KERN_ERR "Failed to allocate device numbers\n");
+		return rc;
+	}
+
+	g_class = class_create(THIS_MODULE, "sharp_class");
+	device_create(g_class, NULL, g_dev, NULL, "sharp");
+
+	cdev_init(&g_cdev, &fops);
+	g_cdev.owner = THIS_MODULE;
+
+	if ((rc = cdev_add(&g_cdev, g_dev, 1))) {
+		unregister_chrdev_region(g_dev, 1);
+		printk(KERN_ERR "Failed to add the character device\n");
+		return rc;
+	}
+
+	printk(KERN_INFO "Character device registered: major = %d, minor = %d\n",
+		MAJOR(g_dev), MINOR(g_dev));
+
 	return 0;
 }
 
 void ioctl_remove(void)
 {
-	return;
+	cdev_del(&g_cdev);
+	device_destroy(g_class, g_dev);
+	class_destroy(g_class);
+	unregister_chrdev_region(g_dev, 1);
+	printk(KERN_INFO "Character device unregistered\n");
 }
diff --git a/params_iface.c b/params_iface.c
index 04726de..5f93512 100644
--- a/params_iface.c
+++ b/params_iface.c
@@ -7,6 +7,7 @@
 
 int g_param_mono_cutoff = 32;
 int g_param_mono_invert = 0;
+int g_param_indicators = 1;
 
 static int set_param_u8(const char *val, const struct kernel_param *kp)
 {
@@ -22,13 +23,6 @@ static int set_param_u8(const char *val, const struct kernel_param *kp)
 	// Refresh framebuffer
 	(void)drm_refresh();
 
-	(void)drm_set_indicator(0, 's');
-	(void)drm_set_indicator(1, 'p');
-	(void)drm_set_indicator(2, 'c');
-	(void)drm_set_indicator(3, 'a');
-	(void)drm_set_indicator(4, 'g');
-	(void)drm_set_indicator(5, 'm');
-
 	return rc;
 }
 
@@ -44,6 +38,9 @@ MODULE_PARM_DESC(mono_cutoff,
 module_param_cb(mono_invert, &u8_param_ops, &g_param_mono_invert, 0660);
 MODULE_PARM_DESC(mono_invert, "0 for no inversion, 1 for inversion");
 
+module_param_cb(indicators, &u8_param_ops, &g_param_indicators, 0660);
+MODULE_PARM_DESC(mono_invert, "0 for no indicators, 1 for indicators");
+
 int params_probe(void)
 {
 	return 0;
@@ -53,3 +50,11 @@ void params_remove(void)
 {
 	return;
 }
+
+void params_set_mono_invert(int setting)
+{
+	g_param_mono_invert = setting;
+
+	// Refresh framebuffer
+	(void)drm_refresh();
+}
diff --git a/params_iface.h b/params_iface.h
index e62ec62..2d15730 100644
--- a/params_iface.h
+++ b/params_iface.h
@@ -3,8 +3,11 @@
 
 extern int g_param_mono_cutoff;
 extern int g_param_mono_invert;
+extern int g_param_indicators;
 
 int params_probe(void);
 void params_remove(void);
 
+void params_set_mono_invert(int setting);
+
 #endif