Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux

Pull devicetree changes from Grant Likely:
 "Lots of activity in the devicetree code for v3.18.  Most of it is
  related to getting all of the overlay support code in place, but there
  are other important things in there.

  Highlights:

   - OF_RECONFIG notifiers for SPI, I2C and Platform devices.  Those
     subsystems can now respond to live changes to the device tree.

   - CONFIG_OF_OVERLAY method for applying live changes to the device
     tree

   - Removal of the of_allnodes list.  This used to be used to iterate
     over all the nodes in the device tree, but it is unnecessary
     because the same thing can be done by iterating over the list of
     child pointers.  Getting rid of of_allnodes saves some memory and
     avoids the possibility of of_allnodes being sorted differently from
     the child lists.

   - Support for retrieving original DTB blob via sysfs.  Needed by
     kexec.

   - More unittests

   - Documentation and minor bug fixes"

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (42 commits)
  of: Delete unnecessary check before calling "of_node_put()"
  of: Drop ->next pointer from struct device_node
  spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y
  of: support passing console options with stdout-path
  of: add optional options parameter to of_find_node_by_path()
  of: Add bindings for chosen node, stdout-path
  of: Remove unneeded and incorrect MODULE_DEVICE_TABLE
  ARM: dt: fix up PL011 device tree bindings
  of: base, fix of_property_read_string_helper kernel-doc
  of: remove select of non-existant OF_DEVICE config symbol
  spi/of: Add OF notifier handler
  spi/of: Create new device registration method and accessors
  i2c/of: Add OF_RECONFIG notifier handler
  i2c/of: Factor out Devicetree registration code
  of/overlay: Add overlay unittests
  of/overlay: Introduce DT overlay support
  of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type
  of/reconfig: Always use the same structure for notifiers
  of/reconfig: Add debug output for OF_RECONFIG notifiers
  of/reconfig: Add empty stubs for the of_reconfig methods
  ...

1 files changed, 104 insertions, 45 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 68aeb8eedae0..229a89e84b0f 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -49,6 +49,7 @@
 #include <linux/acpi.h>
 #include <linux/jump_label.h>
 #include <asm/uaccess.h>
+#include <linux/err.h>
 
 #include "i2c-core.h"
 
@@ -1369,63 +1370,69 @@ static void i2c_scan_static_board_info(struct i2c_adapter *adapter)
 /* OF support code */
 
 #if IS_ENABLED(CONFIG_OF)
-static void of_i2c_register_devices(struct i2c_adapter *adap)
+static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
+                                                 struct device_node *node)
 {
-        void *result;
-        struct device_node *node;
+        struct i2c_client *result;
+        struct i2c_board_info info = {};
+        struct dev_archdata dev_ad = {};
+        const __be32 *addr;
+        int len;
 
-        /* Only register child devices if the adapter has a node pointer set */
-        if (!adap->dev.of_node)
-                return;
+        dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
 
-        dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
+        if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
+                dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
+                        node->full_name);
+                return ERR_PTR(-EINVAL);
+        }
 
-        for_each_available_child_of_node(adap->dev.of_node, node) {
-                struct i2c_board_info info = {};
-                struct dev_archdata dev_ad = {};
-                const __be32 *addr;
-                int len;
+        addr = of_get_property(node, "reg", &len);
+        if (!addr || (len < sizeof(int))) {
+                dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
+                        node->full_name);
+                return ERR_PTR(-EINVAL);
+        }
 
-                dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
+        info.addr = be32_to_cpup(addr);
+        if (info.addr > (1 << 10) - 1) {
+                dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
+                        info.addr, node->full_name);
+                return ERR_PTR(-EINVAL);
+        }
 
-                if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
-                        dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
-                                node->full_name);
-                        continue;
-                }
+        info.irq = irq_of_parse_and_map(node, 0);
+        info.of_node = of_node_get(node);
+        info.archdata = &dev_ad;
 
-                addr = of_get_property(node, "reg", &len);
-                if (!addr || (len < sizeof(int))) {
-                        dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
-                                node->full_name);
-                        continue;
-                }
+        if (of_get_property(node, "wakeup-source", NULL))
+                info.flags |= I2C_CLIENT_WAKE;
 
-                info.addr = be32_to_cpup(addr);
-                if (info.addr > (1 << 10) - 1) {
-                        dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
-                                info.addr, node->full_name);
-                        continue;
-                }
+        request_module("%s%s", I2C_MODULE_PREFIX, info.type);
+
+        result = i2c_new_device(adap, &info);
+        if (result == NULL) {
+                dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
+                        node->full_name);
+                of_node_put(node);
+                irq_dispose_mapping(info.irq);
+                return ERR_PTR(-EINVAL);
+        }
+        return result;
+}
 
-                info.irq = irq_of_parse_and_map(node, 0);
-                info.of_node = of_node_get(node);
-                info.archdata = &dev_ad;
+static void of_i2c_register_devices(struct i2c_adapter *adap)
+{
+        struct device_node *node;
 
-                if (of_get_property(node, "wakeup-source", NULL))
-                        info.flags |= I2C_CLIENT_WAKE;
+        /* Only register child devices if the adapter has a node pointer set */
+        if (!adap->dev.of_node)
+                return;
 
-                request_module("%s%s", I2C_MODULE_PREFIX, info.type);
+        dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
 
-                result = i2c_new_device(adap, &info);
-                if (result == NULL) {
-                        dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
-                                node->full_name);
-                        of_node_put(node);
-                        irq_dispose_mapping(info.irq);
-                        continue;
-                }
-        }
+        for_each_available_child_of_node(adap->dev.of_node, node)
+                of_i2c_register_device(adap, node);
 }
 
 static int of_dev_node_match(struct device *dev, void *data)
@@ -1945,6 +1952,52 @@ void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg)
 }
 EXPORT_SYMBOL(i2c_clients_command);
 
+#if IS_ENABLED(CONFIG_OF_DYNAMIC)
+static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
+                         void *arg)
+{
+        struct of_reconfig_data *rd = arg;
+        struct i2c_adapter *adap;
+        struct i2c_client *client;
+
+        switch (of_reconfig_get_state_change(action, rd)) {
+        case OF_RECONFIG_CHANGE_ADD:
+                adap = of_find_i2c_adapter_by_node(rd->dn->parent);
+                if (adap == NULL)
+                        return NOTIFY_OK;       /* not for us */
+
+                client = of_i2c_register_device(adap, rd->dn);
+                put_device(&adap->dev);
+
+                if (IS_ERR(client)) {
+                        pr_err("%s: failed to create for '%s'\n",
+                                        __func__, rd->dn->full_name);
+                        return notifier_from_errno(PTR_ERR(client));
+                }
+                break;
+        case OF_RECONFIG_CHANGE_REMOVE:
+                /* find our device by node */
+                client = of_find_i2c_device_by_node(rd->dn);
+                if (client == NULL)
+                        return NOTIFY_OK;       /* no? not meant for us */
+
+                /* unregister takes one ref away */
+                i2c_unregister_device(client);
+
+                /* and put the reference of the find */
+                put_device(&client->dev);
+                break;
+        }
+
+        return NOTIFY_OK;
+}
+static struct notifier_block i2c_of_notifier = {
+        .notifier_call = of_i2c_notify,
+};
+#else
+extern struct notifier_block i2c_of_notifier;
+#endif /* CONFIG_OF_DYNAMIC */
+
 static int __init i2c_init(void)
 {
         int retval;
@@ -1962,6 +2015,10 @@ static int __init i2c_init(void)
         retval = i2c_add_driver(&dummy_driver);
         if (retval)
                 goto class_err;
+
+        if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+                WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier));
+
         return 0;
 
 class_err:
@@ -1975,6 +2032,8 @@ bus_err:
 
 static void __exit i2c_exit(void)
 {
+        if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+                WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier));
         i2c_del_driver(&dummy_driver);
 #ifdef CONFIG_I2C_COMPAT
         class_compat_unregister(i2c_adapter_compat_class);