[PATCH] powerpc: use the device tree for the iSeries vio bus probe

As an added bonus, since every vio_dev now has a device_node
associated with it, hotplug now works.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 143 insertions, 28 deletions

diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index 971020cf3f7d..9b46eed5e637 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -22,9 +22,7 @@
 #include <asm/dma.h>
 #include <asm/vio.h>
 #include <asm/prom.h>
-
-static const struct vio_device_id *vio_match_device(
-                const struct vio_device_id *, const struct vio_dev *);
+#include <asm/firmware.h>
 
 struct vio_dev vio_bus_device  = { /* fake "parent" device */
         .name = vio_bus_device.dev.bus_id,
@@ -35,6 +33,27 @@ struct vio_dev vio_bus_device  = { /* fake "parent" device */
 
 static struct vio_bus_ops vio_bus_ops;
 
+/**
+ * vio_match_device: - Tell if a VIO device has a matching
+ *                      VIO device id structure.
+ * @ids:        array of VIO device id structures to search in
+ * @dev:        the VIO device structure to match against
+ *
+ * Used by a driver to check whether a VIO device present in the
+ * system is in its list of supported devices. Returns the matching
+ * vio_device_id structure or NULL if there is no match.
+ */
+static const struct vio_device_id *vio_match_device(
+                const struct vio_device_id *ids, const struct vio_dev *dev)
+{
+        while (ids->type[0] != '\0') {
+                if (vio_bus_ops.match(ids, dev))
+                        return ids;
+                ids++;
+        }
+        return NULL;
+}
+
 /*
  * Convert from struct device to struct vio_dev and pass to driver.
  * dev->driver has already been set by generic code because vio_bus_match
@@ -107,25 +126,76 @@ void vio_unregister_driver(struct vio_driver *viodrv)
 EXPORT_SYMBOL(vio_unregister_driver);
 
 /**
- * vio_match_device: - Tell if a VIO device has a matching
- *                      VIO device id structure.
- * @ids:        array of VIO device id structures to search in
- * @dev:        the VIO device structure to match against
+ * vio_register_device_node: - Register a new vio device.
+ * @of_node:    The OF node for this device.
  *
- * Used by a driver to check whether a VIO device present in the
- * system is in its list of supported devices. Returns the matching
- * vio_device_id structure or NULL if there is no match.
+ * Creates and initializes a vio_dev structure from the data in
+ * of_node (dev.platform_data) and adds it to the list of virtual devices.
+ * Returns a pointer to the created vio_dev or NULL if node has
+ * NULL device_type or compatible fields.
  */
-static const struct vio_device_id *vio_match_device(
-                const struct vio_device_id *ids, const struct vio_dev *dev)
+struct vio_dev * __devinit vio_register_device_node(struct device_node *of_node)
 {
-        while (ids->type[0] != '\0') {
-                if (vio_bus_ops.match(ids, dev))
-                        return ids;
-                ids++;
+        struct vio_dev *viodev;
+        unsigned int *unit_address;
+        unsigned int *irq_p;
+
+        /* we need the 'device_type' property, in order to match with drivers */
+        if (of_node->type == NULL) {
+                printk(KERN_WARNING "%s: node %s missing 'device_type'\n",
+                                __FUNCTION__,
+                                of_node->name ? of_node->name : "<unknown>");
+                return NULL;
         }
-        return NULL;
+
+        unit_address = (unsigned int *)get_property(of_node, "reg", NULL);
+        if (unit_address == NULL) {
+                printk(KERN_WARNING "%s: node %s missing 'reg'\n",
+                                __FUNCTION__,
+                                of_node->name ? of_node->name : "<unknown>");
+                return NULL;
+        }
+
+        /* allocate a vio_dev for this node */
+        viodev = kzalloc(sizeof(struct vio_dev), GFP_KERNEL);
+        if (viodev == NULL)
+                return NULL;
+
+        viodev->dev.platform_data = of_node_get(of_node);
+
+        viodev->irq = NO_IRQ;
+        irq_p = (unsigned int *)get_property(of_node, "interrupts", NULL);
+        if (irq_p) {
+                int virq = virt_irq_create_mapping(*irq_p);
+                if (virq == NO_IRQ) {
+                        printk(KERN_ERR "Unable to allocate interrupt "
+                               "number for %s\n", of_node->full_name);
+                } else
+                        viodev->irq = irq_offset_up(virq);
+        }
+
+        snprintf(viodev->dev.bus_id, BUS_ID_SIZE, "%x", *unit_address);
+        viodev->name = of_node->name;
+        viodev->type = of_node->type;
+        viodev->unit_address = *unit_address;
+        if (firmware_has_feature(FW_FEATURE_ISERIES)) {
+                unit_address = (unsigned int *)get_property(of_node,
+                                "linux,unit_address", NULL);
+                if (unit_address != NULL)
+                        viodev->unit_address = *unit_address;
+        }
+        viodev->iommu_table = vio_bus_ops.build_iommu_table(viodev);
+
+        /* register with generic device framework */
+        if (vio_register_device(viodev) == NULL) {
+                /* XXX free TCE table */
+                kfree(viodev);
+                return NULL;
+        }
+
+        return viodev;
 }
+EXPORT_SYMBOL(vio_register_device_node);
 
 /**
  * vio_bus_init: - Initialize the virtual IO bus
@@ -133,6 +203,7 @@ static const struct vio_device_id *vio_match_device(
 int __init vio_bus_init(struct vio_bus_ops *ops)
 {
         int err;
+        struct device_node *node_vroot;
 
         vio_bus_ops = *ops;
 
@@ -153,23 +224,54 @@ int __init vio_bus_init(struct vio_bus_ops *ops)
                 return err;
         }
 
+        node_vroot = find_devices("vdevice");
+        if (node_vroot) {
+                struct device_node *of_node;
+
+                /*
+                 * Create struct vio_devices for each virtual device in
+                 * the device tree. Drivers will associate with them later.
+                 */
+                for (of_node = node_vroot->child; of_node != NULL;
+                                of_node = of_node->sibling) {
+                        printk(KERN_DEBUG "%s: processing %p\n",
+                                        __FUNCTION__, of_node);
+                        vio_register_device_node(of_node);
+                }
+        }
+
         return 0;
 }
 
 /* vio_dev refcount hit 0 */
 static void __devinit vio_dev_release(struct device *dev)
 {
-        if (vio_bus_ops.release_device)
-                vio_bus_ops.release_device(dev);
+        if (dev->platform_data) {
+                /* XXX free TCE table */
+                of_node_put(dev->platform_data);
+        }
         kfree(to_vio_dev(dev));
 }
 
-static ssize_t viodev_show_name(struct device *dev,
+static ssize_t name_show(struct device *dev,
                 struct device_attribute *attr, char *buf)
 {
         return sprintf(buf, "%s\n", to_vio_dev(dev)->name);
 }
-DEVICE_ATTR(name, S_IRUSR | S_IRGRP | S_IROTH, viodev_show_name, NULL);
+
+static ssize_t devspec_show(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        struct device_node *of_node = dev->platform_data;
+
+        return sprintf(buf, "%s\n", of_node ? of_node->full_name : "none");
+}
+
+static struct device_attribute vio_dev_attrs[] = {
+        __ATTR_RO(name),
+        __ATTR_RO(devspec),
+        __ATTR_NULL
+};
 
 struct vio_dev * __devinit vio_register_device(struct vio_dev *viodev)
 {
@@ -184,16 +286,12 @@ struct vio_dev * __devinit vio_register_device(struct vio_dev *viodev)
                                 __FUNCTION__, viodev->dev.bus_id);
                 return NULL;
         }
-        device_create_file(&viodev->dev, &dev_attr_name);
 
         return viodev;
 }
 
 void __devinit vio_unregister_device(struct vio_dev *viodev)
 {
-        if (vio_bus_ops.unregister_device)
-                vio_bus_ops.unregister_device(viodev);
-        device_remove_file(&viodev->dev, &dev_attr_name);
         device_unregister(&viodev->dev);
 }
 EXPORT_SYMBOL(vio_unregister_device);
@@ -267,22 +365,23 @@ static int vio_hotplug(struct device *dev, char **envp, int num_envp,
                         char *buffer, int buffer_size)
 {
         const struct vio_dev *vio_dev = to_vio_dev(dev);
+        struct device_node *dn = dev->platform_data;
         char *cp;
         int length;
 
         if (!num_envp)
                 return -ENOMEM;
 
-        if (!vio_dev->dev.platform_data)
+        if (!dn)
                 return -ENODEV;
-        cp = (char *)get_property(vio_dev->dev.platform_data, "compatible", &length);
+        cp = (char *)get_property(dn, "compatible", &length);
         if (!cp)
                 return -ENODEV;
 
         envp[0] = buffer;
         length = scnprintf(buffer, buffer_size, "MODALIAS=vio:T%sS%s",
                                 vio_dev->type, cp);
-        if (buffer_size - length <= 0)
+        if ((buffer_size - length) <= 0)
                 return -ENOMEM;
         envp[1] = NULL;
         return 0;
@@ -290,9 +389,25 @@ static int vio_hotplug(struct device *dev, char **envp, int num_envp,
 
 struct bus_type vio_bus_type = {
         .name = "vio",
+        .dev_attrs = vio_dev_attrs,
         .uevent = vio_hotplug,
         .match = vio_bus_match,
         .probe = vio_bus_probe,
         .remove = vio_bus_remove,
         .shutdown = vio_bus_shutdown,
 };
+
+/**
+ * vio_get_attribute: - get attribute for virtual device
+ * @vdev:       The vio device to get property.
+ * @which:      The property/attribute to be extracted.
+ * @length:     Pointer to length of returned data size (unused if NULL).
+ *
+ * Calls prom.c's get_property() to return the value of the
+ * attribute specified by @which
+*/
+const void *vio_get_attribute(struct vio_dev *vdev, char *which, int *length)
+{
+        return get_property(vdev->dev.platform_data, which, length);
+}
+EXPORT_SYMBOL(vio_get_attribute);