dev: implement bus device enumeration

dev/bus.c

@@ -1,4 +1,8 @@
 #include <socks/device.h>
+#include <socks/libc/stdio.h>
+
+static struct queue all_buses;
+static spin_lock_t all_buses_lock;
 
 struct bus_device *bus_device_create(void)
 {
@@ -11,3 +15,43 @@ struct bus_device *bus_device_create(void)
 
 	return BUS_DEVICE(dev);
 }
+
+kern_status_t scan_all_buses(void)
+{
+	kern_status_t status = KERN_OK;
+
+	/* keep interrupts enabled while scanning for devices */
+	spin_lock(&all_buses_lock);
+
+	queue_foreach(struct bus_device, bus, &all_buses, b_buslist) {
+		if (bus->b_ops && bus->b_ops->scan) {
+			status = bus->b_ops->scan(bus_device_base(bus));
+		}
+
+		if (status != KERN_OK) {
+			break;
+		}
+	}
+
+	spin_unlock(&all_buses_lock);
+	return status;
+}
+
+static kern_status_t bus_device_register(struct device *dev)
+{
+	struct bus_device *bus = &dev->bus;
+
+	unsigned long flags;
+	spin_lock_irqsave(&all_buses_lock, &flags);
+	queue_push_back(&all_buses, &bus->b_buslist);
+	spin_unlock_irqrestore(&all_buses_lock, flags);
+
+	char path[OBJECT_PATH_MAX];
+	snprintf(path, sizeof path, "/dev/bus/%s", dev->dev_name);
+
+	return object_namespace_create_link(global_namespace(), path, &dev->dev_base);
+}
+
+struct device_type_ops bus_type_ops = {
+	.register_device = bus_device_register,
+};

dev/core.c

@@ -21,6 +21,7 @@ extern kern_status_t init_driver_tree(void);
 
 extern struct device_type_ops input_type_ops;
 extern struct device_type_ops framebuffer_type_ops;
+extern struct device_type_ops bus_type_ops;
 
 static struct device_type_ops *type_ops[] = {
 	[DEV_TYPE_UNKNOWN] = NULL,
@@ -28,7 +29,7 @@ static struct device_type_ops *type_ops[] = {
 	[DEV_TYPE_CHAR] = NULL,
 	[DEV_TYPE_NET] = NULL,
 	[DEV_TYPE_INPUT] = &input_type_ops,
-	[DEV_TYPE_BUS] = NULL,
+	[DEV_TYPE_BUS] = &bus_type_ops,
 	[DEV_TYPE_FRAMEBUFFER] = &framebuffer_type_ops,
 };
 
@@ -108,6 +109,18 @@ struct device *device_alloc(void)
 	return DEVICE_CAST(dev_object);
 }
 
+struct device *generic_device_create(void)
+{
+	struct device *dev = device_alloc();
+	if (!dev) {
+		return NULL;
+	}
+
+	dev->dev_type = DEV_TYPE_UNKNOWN;
+
+	return dev;
+}
+
 kern_status_t device_read(struct device *dev, void *buf, size_t size, size_t *bytes_read, socks_flags_t flags)
 {
 	switch (dev->dev_type) {