Commit e5050143 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 

Pull more i2c updates from Wolfram Sang:
 "A small update pull request from I2C.

  This adds one comment to a change we did in this merge window to
  handle lockdep better, and pulls in a branch which should have been in
  4.8 already improving DT support for I2C"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  gpio: pca953x: add a comment explaining the need for a lockdep subclass
  i2c: core: Add support for 'i2c-bus' subnode
  dt-bindings: i2c: Add support for 'i2c-bus' subnode
parents b41d037a b2edcdae

Documentation/devicetree/bindings/i2c/i2c.txt

+8 −0
Original line number Diff line number Diff line
@@ -32,6 +32,14 @@ wants to support one of the below features, it should adapt the bindings below. 
- clock-frequency

	frequency of bus clock in Hz.



- i2c-bus

	For I2C adapters that have child nodes that are a mixture of both I2C

	devices and non-I2C devices, the 'i2c-bus' subnode can be used for

	populating I2C devices. If the 'i2c-bus' subnode is present, only

	subnodes of this will be considered as I2C slaves. The properties,

	'#address-cells' and '#size-cells' must be defined under this subnode

	if present.



- i2c-scl-falling-time-ns

	Number of nanoseconds the SCL signal takes to fall; t(f) in the I2C

	specification.

drivers/gpio/gpio-pca953x.c

+16 −0
Original line number Diff line number Diff line
@@ -794,6 +794,22 @@ static int pca953x_probe(struct i2c_client *client, 
	}



	mutex_init(&chip->i2c_lock);

	/*

	 * In case we have an i2c-mux controlled by a GPIO provided by an

	 * expander using the same driver higher on the device tree, read the

	 * i2c adapter nesting depth and use the retrieved value as lockdep

	 * subclass for chip->i2c_lock.

	 *

	 * REVISIT: This solution is not complete. It protects us from lockdep

	 * false positives when the expander controlling the i2c-mux is on

	 * a different level on the device tree, but not when it's on the same

	 * level on a different branch (in which case the subclass number

	 * would be the same).

	 *

	 * TODO: Once a correct solution is developed, a similar fix should be

	 * applied to all other i2c-controlled GPIO expanders (and potentially

	 * regmap-i2c).

	 */

	lockdep_set_subclass(&chip->i2c_lock,

			     i2c_adapter_depth(client->adapter));

drivers/i2c/i2c-core.c

+8 −2
Original line number Diff line number Diff line
@@ -1680,7 +1680,7 @@ static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap, 


static void of_i2c_register_devices(struct i2c_adapter *adap)

{

	struct device_node *node;

	struct device_node *bus, *node;



	/* Only register child devices if the adapter has a node pointer set */

	if (!adap->dev.of_node)
@@ -1688,11 +1688,17 @@ 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) {

	bus = of_get_child_by_name(adap->dev.of_node, "i2c-bus");

	if (!bus)

		bus = of_node_get(adap->dev.of_node);



	for_each_available_child_of_node(bus, node) {

		if (of_node_test_and_set_flag(node, OF_POPULATED))

			continue;

		of_i2c_register_device(adap, node);

	}



	of_node_put(bus);

}



static int of_dev_node_match(struct device *dev, void *data)

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