dev: auto-generate device name in device_register if name is unspecified

dev/core.c

@@ -37,6 +37,18 @@ static kern_status_t set_root_device(struct device *dev)
 	return KERN_OK;
 }
 
+static kern_status_t device_generate_name(struct device *dev)
+{
+	switch (dev->dev_type) {
+	case DEV_TYPE_INPUT:
+		return input_device_generate_name(&dev->input);
+	default:
+		break;
+	}
+
+	return KERN_UNSUPPORTED;
+}
+
 kern_status_t device_init(void)
 {
 	object_type_register(&device_type);
@@ -157,6 +169,15 @@ kern_status_t device_register(struct device *dev, struct device *parent)
 
 	kern_status_t status = KERN_OK;
 
+	if (dev->dev_name[0] == 0) {
+		status = device_generate_name(dev);
+	}
+
+	if (status != KERN_OK) {
+		device_unlock_irqrestore(dev, flags);
+		return status;
+	}
+
 	queue_foreach (struct device, child, &dev->dev_children, dev_childent) {
 		if (!strcmp(dev->dev_name, child->dev_name)) {
 			status = KERN_NAME_EXISTS;

dev/input.c

@@ -1,5 +1,10 @@
 #include <socks/device.h>
 #include <socks/input.h>
+#include <socks/bitmap.h>
+#include <socks/libc/stdio.h>
+
+static DECLARE_BITMAP(input_device_ids, INPUT_DEVICE_MAX);
+static spin_lock_t input_device_ids_lock = SPIN_LOCK_INIT;
 
 struct input_device *input_device_create(void)
 {
@@ -16,6 +21,14 @@ struct input_device *input_device_create(void)
 		return NULL;
 	}
 
+	unsigned long flags;
+	spin_lock_irqsave(&input_device_ids_lock, &flags);
+	unsigned int id = bitmap_lowest_clear(input_device_ids, INPUT_DEVICE_MAX);
+	bitmap_set(input_device_ids, id);
+	spin_unlock_irqrestore(&input_device_ids_lock, flags);
+
+	input_dev->i_id = id;
+
 	return INPUT_DEVICE(dev);
 }
 
@@ -49,3 +62,10 @@ kern_status_t input_device_read(struct device *dev, void *buf, size_t size, size
 
 	return KERN_OK;
 }
+
+kern_status_t input_device_generate_name(struct input_device *dev)
+{
+	struct device *d = input_device_base(dev);
+	snprintf(d->dev_name, sizeof d->dev_name, "input%u", dev->i_id);
+	return KERN_OK;
+}