summaryrefslogtreecommitdiff
path: root/drivers/of/kobj.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-14 18:25:40 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-14 18:25:40 -0800
commit37cb8e1f8e10c6e9bd2a1b95cdda0620a21b0551 (patch)
treea1302a6cd2978d7a089534b8232ef3bfa921610e /drivers/of/kobj.c
parent6a77d86655a1f22f099e5c73eef61dea9c56d633 (diff)
parentaa25e446ce76c37bfd75ac06598c316af94e9a26 (diff)
Merge tag 'devicetree-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull DeviceTree updates from Rob Herring: "A bigger diffstat than usual with the kbuild changes and a tree wide fix in the binding documentation. Summary: - kbuild cleanups and improvements for dtbs - Code clean-up of overlay code and fixing for some long standing memory leak and race condition in applying overlays - Improvements to DT memory usage making sysfs/kobjects optional and skipping unflattening of disabled nodes. This is part of kernel tinification efforts. - Final piece of removing storing the full path for every DT node. The prerequisite conversion of printk's to use device_node format specifier happened in 4.14. - Sync with current upstream dtc. This brings additional checks to dtb compiling. - Binding doc tree wide removal of leading 0s from examples - RTC binding documentation adding missing devices and some consolidation of duplicated bindings - Vendor prefix documentation for nutsboard, Silicon Storage Technology, shimafuji, Tecon Microprocessor Technologies, DH electronics GmbH, Opal Kelly, and Next Thing" * tag 'devicetree-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (55 commits) dt-bindings: usb: add #phy-cells to usb-nop-xceiv dt-bindings: Remove leading zeros from bindings notation kbuild: handle dtb-y and CONFIG_OF_ALL_DTBS natively in Makefile.lib MIPS: dts: remove bogus bcm96358nb4ser.dtb from dtb-y entry kbuild: clean up *.dtb and *.dtb.S patterns from top-level Makefile .gitignore: move *.dtb and *.dtb.S patterns to the top-level .gitignore .gitignore: sort normal pattern rules alphabetically dt-bindings: add vendor prefix for Next Thing Co. scripts/dtc: Update to upstream version v1.4.5-6-gc1e55a5513e9 of: dynamic: fix memory leak related to properties of __of_node_dup of: overlay: make pr_err() string unique of: overlay: pr_err from return NOTIFY_OK to overlay apply/remove of: overlay: remove unneeded check for NULL kbasename() of: overlay: remove a dependency on device node full_name of: overlay: simplify applying symbols from an overlay of: overlay: avoid race condition between applying multiple overlays of: overlay: loosen overly strict phandle clash check of: overlay: expand check of whether overlay changeset can be removed of: overlay: detect cases where device tree may become corrupt of: overlay: minor restructuring ...
Diffstat (limited to 'drivers/of/kobj.c')
-rw-r--r--drivers/of/kobj.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/of/kobj.c b/drivers/of/kobj.c
new file mode 100644
index 000000000000..250fc7bb550f
--- /dev/null
+++ b/drivers/of/kobj.c
@@ -0,0 +1,164 @@
+#include <linux/of.h>
+#include <linux/slab.h>
+
+#include "of_private.h"
+
+/* true when node is initialized */
+static int of_node_is_initialized(struct device_node *node)
+{
+ return node && node->kobj.state_initialized;
+}
+
+/* true when node is attached (i.e. present on sysfs) */
+int of_node_is_attached(struct device_node *node)
+{
+ return node && node->kobj.state_in_sysfs;
+}
+
+
+#ifndef CONFIG_OF_DYNAMIC
+static void of_node_release(struct kobject *kobj)
+{
+ /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */
+}
+#endif /* CONFIG_OF_DYNAMIC */
+
+struct kobj_type of_node_ktype = {
+ .release = of_node_release,
+};
+
+static ssize_t of_node_property_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t offset, size_t count)
+{
+ struct property *pp = container_of(bin_attr, struct property, attr);
+ return memory_read_from_buffer(buf, count, &offset, pp->value, pp->length);
+}
+
+/* always return newly allocated name, caller must free after use */
+static const char *safe_name(struct kobject *kobj, const char *orig_name)
+{
+ const char *name = orig_name;
+ struct kernfs_node *kn;
+ int i = 0;
+
+ /* don't be a hero. After 16 tries give up */
+ while (i < 16 && (kn = sysfs_get_dirent(kobj->sd, name))) {
+ sysfs_put(kn);
+ if (name != orig_name)
+ kfree(name);
+ name = kasprintf(GFP_KERNEL, "%s#%i", orig_name, ++i);
+ }
+
+ if (name == orig_name) {
+ name = kstrdup(orig_name, GFP_KERNEL);
+ } else {
+ pr_warn("Duplicate name in %s, renamed to \"%s\"\n",
+ kobject_name(kobj), name);
+ }
+ return name;
+}
+
+int __of_add_property_sysfs(struct device_node *np, struct property *pp)
+{
+ int rc;
+
+ /* Important: Don't leak passwords */
+ bool secure = strncmp(pp->name, "security-", 9) == 0;
+
+ if (!IS_ENABLED(CONFIG_SYSFS))
+ return 0;
+
+ if (!of_kset || !of_node_is_attached(np))
+ return 0;
+
+ sysfs_bin_attr_init(&pp->attr);
+ pp->attr.attr.name = safe_name(&np->kobj, pp->name);
+ pp->attr.attr.mode = secure ? 0400 : 0444;
+ pp->attr.size = secure ? 0 : pp->length;
+ pp->attr.read = of_node_property_read;
+
+ rc = sysfs_create_bin_file(&np->kobj, &pp->attr);
+ WARN(rc, "error adding attribute %s to node %pOF\n", pp->name, np);
+ return rc;
+}
+
+void __of_sysfs_remove_bin_file(struct device_node *np, struct property *prop)
+{
+ if (!IS_ENABLED(CONFIG_SYSFS))
+ return;
+
+ sysfs_remove_bin_file(&np->kobj, &prop->attr);
+ kfree(prop->attr.attr.name);
+}
+
+void __of_remove_property_sysfs(struct device_node *np, struct property *prop)
+{
+ /* at early boot, bail here and defer setup to of_init() */
+ if (of_kset && of_node_is_attached(np))
+ __of_sysfs_remove_bin_file(np, prop);
+}
+
+void __of_update_property_sysfs(struct device_node *np, struct property *newprop,
+ struct property *oldprop)
+{
+ /* At early boot, bail out and defer setup to of_init() */
+ if (!of_kset)
+ return;
+
+ if (oldprop)
+ __of_sysfs_remove_bin_file(np, oldprop);
+ __of_add_property_sysfs(np, newprop);
+}
+
+int __of_attach_node_sysfs(struct device_node *np)
+{
+ const char *name;
+ struct kobject *parent;
+ struct property *pp;
+ int rc;
+
+ if (!of_kset)
+ return 0;
+
+ np->kobj.kset = of_kset;
+ if (!np->parent) {
+ /* Nodes without parents are new top level trees */
+ name = safe_name(&of_kset->kobj, "base");
+ parent = NULL;
+ } else {
+ name = safe_name(&np->parent->kobj, kbasename(np->full_name));
+ parent = &np->parent->kobj;
+ }
+ if (!name)
+ return -ENOMEM;
+ rc = kobject_add(&np->kobj, parent, "%s", name);
+ kfree(name);
+ if (rc)
+ return rc;
+
+ for_each_property_of_node(np, pp)
+ __of_add_property_sysfs(np, pp);
+
+ return 0;
+}
+
+void __of_detach_node_sysfs(struct device_node *np)
+{
+ struct property *pp;
+
+ BUG_ON(!of_node_is_initialized(np));
+ if (!of_kset)
+ return;
+
+ /* only remove properties if on sysfs */
+ if (of_node_is_attached(np)) {
+ for_each_property_of_node(np, pp)
+ __of_sysfs_remove_bin_file(np, pp);
+ kobject_del(&np->kobj);
+ }
+
+ /* finally remove the kobj_init ref */
+ of_node_put(np);
+}
+