#include <linux/of_device.h>
#include <linux/of_graph.h>
#include <linux/string.h>
+#include <linux/moduleparam.h>
#include "of_private.h"
of_property_count_strings(node, propname);
}
+static const char *of_fwnode_get_name(const struct fwnode_handle *fwnode)
+{
+ return kbasename(to_of_node(fwnode)->full_name);
+}
+
+static const char *of_fwnode_get_name_prefix(const struct fwnode_handle *fwnode)
+{
+ /* Root needs no prefix here (its name is "/"). */
+ if (!to_of_node(fwnode)->parent)
+ return "";
+
+ return "/";
+}
+
static struct fwnode_handle *
of_fwnode_get_parent(const struct fwnode_handle *fwnode)
{
return of_device_get_match_data(dev);
}
+static bool of_is_ancestor_of(struct device_node *test_ancestor,
+ struct device_node *child)
+{
+ of_node_get(child);
+ while (child) {
+ if (child == test_ancestor) {
+ of_node_put(child);
+ return true;
+ }
+ child = of_get_next_parent(child);
+ }
+ return false;
+}
+
+/**
+ * of_link_to_phandle - Add device link to supplier from supplier phandle
+ * @dev: consumer device
+ * @sup_np: phandle to supplier device tree node
+ *
+ * Given a phandle to a supplier device tree node (@sup_np), this function
+ * finds the device that owns the supplier device tree node and creates a
+ * device link from @dev consumer device to the supplier device. This function
+ * doesn't create device links for invalid scenarios such as trying to create a
+ * link with a parent device as the consumer of its child device. In such
+ * cases, it returns an error.
+ *
+ * Returns:
+ * - 0 if link successfully created to supplier
+ * - -EAGAIN if linking to the supplier should be reattempted
+ * - -EINVAL if the supplier link is invalid and should not be created
+ * - -ENODEV if there is no device that corresponds to the supplier phandle
+ */
+static int of_link_to_phandle(struct device *dev, struct device_node *sup_np,
+ u32 dl_flags)
+{
+ struct device *sup_dev;
+ int ret = 0;
+ struct device_node *tmp_np = sup_np;
+ int is_populated;
+
+ of_node_get(sup_np);
+ /*
+ * Find the device node that contains the supplier phandle. It may be
+ * @sup_np or it may be an ancestor of @sup_np.
+ */
+ while (sup_np && !of_find_property(sup_np, "compatible", NULL))
+ sup_np = of_get_next_parent(sup_np);
+ if (!sup_np) {
+ dev_dbg(dev, "Not linking to %pOFP - No device\n", tmp_np);
+ return -ENODEV;
+ }
+
+ /*
+ * Don't allow linking a device node as a consumer of one of its
+ * descendant nodes. By definition, a child node can't be a functional
+ * dependency for the parent node.
+ */
+ if (of_is_ancestor_of(dev->of_node, sup_np)) {
+ dev_dbg(dev, "Not linking to %pOFP - is descendant\n", sup_np);
+ of_node_put(sup_np);
+ return -EINVAL;
+ }
+ sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
+ is_populated = of_node_check_flag(sup_np, OF_POPULATED);
+ of_node_put(sup_np);
+ if (!sup_dev && is_populated) {
+ /* Early device without struct device. */
+ dev_dbg(dev, "Not linking to %pOFP - No struct device\n",
+ sup_np);
+ return -ENODEV;
+ } else if (!sup_dev) {
+ return -EAGAIN;
+ }
+ if (!device_link_add(dev, sup_dev, dl_flags))
+ ret = -EAGAIN;
+ put_device(sup_dev);
+ return ret;
+}
+
+/**
+ * parse_prop_cells - Property parsing function for suppliers
+ *
+ * @np: Pointer to device tree node containing a list
+ * @prop_name: Name of property to be parsed. Expected to hold phandle values
+ * @index: For properties holding a list of phandles, this is the index
+ * into the list.
+ * @list_name: Property name that is known to contain list of phandle(s) to
+ * supplier(s)
+ * @cells_name: property name that specifies phandles' arguments count
+ *
+ * This is a helper function to parse properties that have a known fixed name
+ * and are a list of phandles and phandle arguments.
+ *
+ * Returns:
+ * - phandle node pointer with refcount incremented. Caller must of_node_put()
+ * on it when done.
+ * - NULL if no phandle found at index
+ */
+static struct device_node *parse_prop_cells(struct device_node *np,
+ const char *prop_name, int index,
+ const char *list_name,
+ const char *cells_name)
+{
+ struct of_phandle_args sup_args;
+
+ if (strcmp(prop_name, list_name))
+ return NULL;
+
+ if (of_parse_phandle_with_args(np, list_name, cells_name, index,
+ &sup_args))
+ return NULL;
+
+ return sup_args.np;
+}
+
+#define DEFINE_SIMPLE_PROP(fname, name, cells) \
+static struct device_node *parse_##fname(struct device_node *np, \
+ const char *prop_name, int index) \
+{ \
+ return parse_prop_cells(np, prop_name, index, name, cells); \
+}
+
+static int strcmp_suffix(const char *str, const char *suffix)
+{
+ unsigned int len, suffix_len;
+
+ len = strlen(str);
+ suffix_len = strlen(suffix);
+ if (len <= suffix_len)
+ return -1;
+ return strcmp(str + len - suffix_len, suffix);
+}
+
+/**
+ * parse_suffix_prop_cells - Suffix property parsing function for suppliers
+ *
+ * @np: Pointer to device tree node containing a list
+ * @prop_name: Name of property to be parsed. Expected to hold phandle values
+ * @index: For properties holding a list of phandles, this is the index
+ * into the list.
+ * @suffix: Property suffix that is known to contain list of phandle(s) to
+ * supplier(s)
+ * @cells_name: property name that specifies phandles' arguments count
+ *
+ * This is a helper function to parse properties that have a known fixed suffix
+ * and are a list of phandles and phandle arguments.
+ *
+ * Returns:
+ * - phandle node pointer with refcount incremented. Caller must of_node_put()
+ * on it when done.
+ * - NULL if no phandle found at index
+ */
+static struct device_node *parse_suffix_prop_cells(struct device_node *np,
+ const char *prop_name, int index,
+ const char *suffix,
+ const char *cells_name)
+{
+ struct of_phandle_args sup_args;
+
+ if (strcmp_suffix(prop_name, suffix))
+ return NULL;
+
+ if (of_parse_phandle_with_args(np, prop_name, cells_name, index,
+ &sup_args))
+ return NULL;
+
+ return sup_args.np;
+}
+
+#define DEFINE_SUFFIX_PROP(fname, suffix, cells) \
+static struct device_node *parse_##fname(struct device_node *np, \
+ const char *prop_name, int index) \
+{ \
+ return parse_suffix_prop_cells(np, prop_name, index, suffix, cells); \
+}
+
+/**
+ * struct supplier_bindings - Property parsing functions for suppliers
+ *
+ * @parse_prop: function name
+ * parse_prop() finds the node corresponding to a supplier phandle
+ * @parse_prop.np: Pointer to device node holding supplier phandle property
+ * @parse_prop.prop_name: Name of property holding a phandle value
+ * @parse_prop.index: For properties holding a list of phandles, this is the
+ * index into the list
+ *
+ * Returns:
+ * parse_prop() return values are
+ * - phandle node pointer with refcount incremented. Caller must of_node_put()
+ * on it when done.
+ * - NULL if no phandle found at index
+ */
+struct supplier_bindings {
+ struct device_node *(*parse_prop)(struct device_node *np,
+ const char *prop_name, int index);
+};
+
+DEFINE_SIMPLE_PROP(clocks, "clocks", "#clock-cells")
+DEFINE_SIMPLE_PROP(interconnects, "interconnects", "#interconnect-cells")
+DEFINE_SIMPLE_PROP(iommus, "iommus", "#iommu-cells")
+DEFINE_SIMPLE_PROP(mboxes, "mboxes", "#mbox-cells")
+DEFINE_SIMPLE_PROP(io_channels, "io-channel", "#io-channel-cells")
+DEFINE_SIMPLE_PROP(interrupt_parent, "interrupt-parent", NULL)
+DEFINE_SIMPLE_PROP(dmas, "dmas", "#dma-cells")
+DEFINE_SUFFIX_PROP(regulators, "-supply", NULL)
+DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
+DEFINE_SUFFIX_PROP(gpios, "-gpios", "#gpio-cells")
+
+static struct device_node *parse_iommu_maps(struct device_node *np,
+ const char *prop_name, int index)
+{
+ if (strcmp(prop_name, "iommu-map"))
+ return NULL;
+
+ return of_parse_phandle(np, prop_name, (index * 4) + 1);
+}
+
+static const struct supplier_bindings of_supplier_bindings[] = {
+ { .parse_prop = parse_clocks, },
+ { .parse_prop = parse_interconnects, },
+ { .parse_prop = parse_iommus, },
+ { .parse_prop = parse_iommu_maps, },
+ { .parse_prop = parse_mboxes, },
+ { .parse_prop = parse_io_channels, },
+ { .parse_prop = parse_interrupt_parent, },
+ { .parse_prop = parse_dmas, },
+ { .parse_prop = parse_regulators, },
+ { .parse_prop = parse_gpio, },
+ { .parse_prop = parse_gpios, },
+ {}
+};
+
+/**
+ * of_link_property - Create device links to suppliers listed in a property
+ * @dev: Consumer device
+ * @con_np: The consumer device tree node which contains the property
+ * @prop_name: Name of property to be parsed
+ *
+ * This function checks if the property @prop_name that is present in the
+ * @con_np device tree node is one of the known common device tree bindings
+ * that list phandles to suppliers. If @prop_name isn't one, this function
+ * doesn't do anything.
+ *
+ * If @prop_name is one, this function attempts to create device links from the
+ * consumer device @dev to all the devices of the suppliers listed in
+ * @prop_name.
+ *
+ * Any failed attempt to create a device link will NOT result in an immediate
+ * return. of_link_property() must create links to all the available supplier
+ * devices even when attempts to create a link to one or more suppliers fail.
+ */
+static int of_link_property(struct device *dev, struct device_node *con_np,
+ const char *prop_name)
+{
+ struct device_node *phandle;
+ const struct supplier_bindings *s = of_supplier_bindings;
+ unsigned int i = 0;
+ bool matched = false;
+ int ret = 0;
+ u32 dl_flags;
+
+ if (dev->of_node == con_np)
+ dl_flags = DL_FLAG_AUTOPROBE_CONSUMER;
+ else
+ dl_flags = DL_FLAG_SYNC_STATE_ONLY;
+
+ /* Do not stop at first failed link, link all available suppliers. */
+ while (!matched && s->parse_prop) {
+ while ((phandle = s->parse_prop(con_np, prop_name, i))) {
+ matched = true;
+ i++;
+ if (of_link_to_phandle(dev, phandle, dl_flags)
+ == -EAGAIN)
+ ret = -EAGAIN;
+ of_node_put(phandle);
+ }
+ s++;
+ }
+ return ret;
+}
+
+static int of_link_to_suppliers(struct device *dev,
+ struct device_node *con_np)
+{
+ struct device_node *child;
+ struct property *p;
+ int ret = 0;
+
+ for_each_property_of_node(con_np, p)
+ if (of_link_property(dev, con_np, p->name))
+ ret = -ENODEV;
+
+ for_each_child_of_node(con_np, child)
+ if (of_link_to_suppliers(dev, child) && !ret)
+ ret = -EAGAIN;
+
+ return ret;
+}
+
+static bool of_devlink;
+core_param(of_devlink, of_devlink, bool, 0);
+
+static int of_fwnode_add_links(const struct fwnode_handle *fwnode,
+ struct device *dev)
+{
+ if (!of_devlink)
+ return 0;
+
+ if (unlikely(!is_of_node(fwnode)))
+ return 0;
+
+ return of_link_to_suppliers(dev, to_of_node(fwnode));
+}
+
const struct fwnode_operations of_fwnode_ops = {
.get = of_fwnode_get,
.put = of_fwnode_put,
.property_present = of_fwnode_property_present,
.property_read_int_array = of_fwnode_property_read_int_array,
.property_read_string_array = of_fwnode_property_read_string_array,
+ .get_name = of_fwnode_get_name,
+ .get_name_prefix = of_fwnode_get_name_prefix,
.get_parent = of_fwnode_get_parent,
.get_next_child_node = of_fwnode_get_next_child_node,
.get_named_child_node = of_fwnode_get_named_child_node,
.graph_get_remote_endpoint = of_fwnode_graph_get_remote_endpoint,
.graph_get_port_parent = of_fwnode_graph_get_port_parent,
.graph_parse_endpoint = of_fwnode_graph_parse_endpoint,
+ .add_links = of_fwnode_add_links,
};
EXPORT_SYMBOL_GPL(of_fwnode_ops);
git.samba.org / sfrench / cifs-2.6.git / blobdiff