Merge tag 'v4.2-rc2' into patchwork

Linux 4.2-rc2

We need to backport changeset 31f02455455d, with fixes a bug at
include/linux/compiler.h that breaks sparse.

* tag 'v4.2-rc2': (221 commits)
  Linux 4.2-rc2
  Revert "drm/i915: Use crtc_state->active in primary check_plane func"
  freeing unlinked file indefinitely delayed
  fix a braino in ovl_d_select_inode()
  9p: don't leave a half-initialized inode sitting around
  tick/broadcast: Prevent NULL pointer dereference
  selinux: fix mprotect PROT_EXEC regression caused by mm change
  parisc: Fix some PTE/TLB race conditions and optimize __flush_tlb_range based on timing results
  stifb: Implement hardware accelerated copyarea
  nfit: add support for NVDIMM "latch" flag
  nfit: update block I/O path to use PMEM API
  tools/testing/nvdimm: add mock acpi_nfit_flush_address entries to nfit_test
  tools/testing/nvdimm: fix return code for unimplemented commands
  tools/testing/nvdimm: mock ioremap_wt
  pmem: add maintainer for include/linux/pmem.h
  Revert "Input: synaptics - allocate 3 slots to keep stability in image sensors"
  arm64: entry32: remove pointless register assignment
  MIPS: O32: Use compat_sys_getsockopt.
  MIPS: c-r4k: Extend way_string array
  MIPS: Pistachio: Support CDMM & Fast Debug Channel
  ...

1 files changed, 15 insertions, 1 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 069a41f116dd..e6d4935161e4 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1012,6 +1012,8 @@ EXPORT_SYMBOL_GPL(i2c_new_device);
  */
 void i2c_unregister_device(struct i2c_client *client)
 {
+	if (client->dev.of_node)
+		of_node_clear_flag(client->dev.of_node, OF_POPULATED);
 	device_unregister(&client->dev);
 }
 EXPORT_SYMBOL_GPL(i2c_unregister_device);
@@ -1320,8 +1322,11 @@ static void of_i2c_register_devices(struct i2c_adapter *adap)
 
 	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
 
-	for_each_available_child_of_node(adap->dev.of_node, node)
+	for_each_available_child_of_node(adap->dev.of_node, node) {
+		if (of_node_test_and_set_flag(node, OF_POPULATED))
+			continue;
 		of_i2c_register_device(adap, node);
+	}
 }
 
 static int of_dev_node_match(struct device *dev, void *data)
@@ -1853,6 +1858,11 @@ static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
 		if (adap == NULL)
 			return NOTIFY_OK;	/* not for us */
 
+		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) {
+			put_device(&adap->dev);
+			return NOTIFY_OK;
+		}
+
 		client = of_i2c_register_device(adap, rd->dn);
 		put_device(&adap->dev);
 
@@ -1863,6 +1873,10 @@ static int of_i2c_notify(struct notifier_block *nb, unsigned long action,
 		}
 		break;
 	case OF_RECONFIG_CHANGE_REMOVE:
+		/* already depopulated? */
+		if (!of_node_check_flag(rd->dn, OF_POPULATED))
+			return NOTIFY_OK;
+
 		/* find our device by node */
 		client = of_find_i2c_device_by_node(rd->dn);
 		if (client == NULL)