aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/i2c/i2c-core-of.c
diff options
context:
space:
mode:
authorWolfram Sang <wsa@the-dreams.de>2017-05-23 11:50:58 +0200
committerWolfram Sang <wsa@the-dreams.de>2017-05-31 21:01:04 +0200
commit5bf4fa7daea6d5257357b613d0bb81c68e2d1af2 (patch)
tree6965a63f2f48bdb1ee512c1f52e81241bf570c95 /drivers/i2c/i2c-core-of.c
parent22c78d1cce104072747023d2ae0351bf3f97d725 (diff)
i2c: break out OF support into separate file
Also removes some ifdeffery. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/i2c-core-of.c')
-rw-r--r--drivers/i2c/i2c-core-of.c276
1 files changed, 276 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core-of.c b/drivers/i2c/i2c-core-of.c
new file mode 100644
index 000000000000..ccf82fdbcd8e
--- /dev/null
+++ b/drivers/i2c/i2c-core-of.c
@@ -0,0 +1,276 @@
+/*
+ * Linux I2C core OF support code
+ *
+ * Copyright (C) 2008 Jochen Friedrich <jochen@scram.de>
+ * based on a previous patch from Jon Smirl <jonsmirl@gmail.com>
+ *
+ * Copyright (C) 2013 Wolfram Sang <wsa@the-dreams.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+#include <dt-bindings/i2c/i2c.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#include "i2c-core.h"
+
+static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap,
+ struct device_node *node)
+{
+ struct i2c_client *result;
+ struct i2c_board_info info = {};
+ struct dev_archdata dev_ad = {};
+ const __be32 *addr_be;
+ u32 addr;
+ int len;
+
+ dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
+
+ 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);
+ }
+
+ addr_be = of_get_property(node, "reg", &len);
+ if (!addr_be || (len < sizeof(*addr_be))) {
+ dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
+ node->full_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ addr = be32_to_cpup(addr_be);
+ if (addr & I2C_TEN_BIT_ADDRESS) {
+ addr &= ~I2C_TEN_BIT_ADDRESS;
+ info.flags |= I2C_CLIENT_TEN;
+ }
+
+ if (addr & I2C_OWN_SLAVE_ADDRESS) {
+ addr &= ~I2C_OWN_SLAVE_ADDRESS;
+ info.flags |= I2C_CLIENT_SLAVE;
+ }
+
+ if (i2c_check_addr_validity(addr, info.flags)) {
+ dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
+ addr, node->full_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ info.addr = addr;
+ info.of_node = of_node_get(node);
+ info.archdata = &dev_ad;
+
+ if (of_property_read_bool(node, "host-notify"))
+ info.flags |= I2C_CLIENT_HOST_NOTIFY;
+
+ if (of_get_property(node, "wakeup-source", NULL))
+ info.flags |= I2C_CLIENT_WAKE;
+
+ 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);
+ return ERR_PTR(-EINVAL);
+ }
+ return result;
+}
+
+void of_i2c_register_devices(struct i2c_adapter *adap)
+{
+ struct device_node *bus, *node;
+ struct i2c_client *client;
+
+ /* Only register child devices if the adapter has a node pointer set */
+ if (!adap->dev.of_node)
+ return;
+
+ dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
+
+ 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;
+
+ client = of_i2c_register_device(adap, node);
+ if (IS_ERR(client)) {
+ dev_warn(&adap->dev,
+ "Failed to create I2C device for %s\n",
+ node->full_name);
+ of_node_clear_flag(node, OF_POPULATED);
+ }
+ }
+
+ of_node_put(bus);
+}
+
+static int of_dev_node_match(struct device *dev, void *data)
+{
+ return dev->of_node == data;
+}
+
+/* must call put_device() when done with returned i2c_client device */
+struct i2c_client *of_find_i2c_device_by_node(struct device_node *node)
+{
+ struct device *dev;
+ struct i2c_client *client;
+
+ dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
+ if (!dev)
+ return NULL;
+
+ client = i2c_verify_client(dev);
+ if (!client)
+ put_device(dev);
+
+ return client;
+}
+EXPORT_SYMBOL(of_find_i2c_device_by_node);
+
+/* must call put_device() when done with returned i2c_adapter device */
+struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node)
+{
+ struct device *dev;
+ struct i2c_adapter *adapter;
+
+ dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match);
+ if (!dev)
+ return NULL;
+
+ adapter = i2c_verify_adapter(dev);
+ if (!adapter)
+ put_device(dev);
+
+ return adapter;
+}
+EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
+
+/* must call i2c_put_adapter() when done with returned i2c_adapter device */
+struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node)
+{
+ struct i2c_adapter *adapter;
+
+ adapter = of_find_i2c_adapter_by_node(node);
+ if (!adapter)
+ return NULL;
+
+ if (!try_module_get(adapter->owner)) {
+ put_device(&adapter->dev);
+ adapter = NULL;
+ }
+
+ return adapter;
+}
+EXPORT_SYMBOL(of_get_i2c_adapter_by_node);
+
+static const struct of_device_id*
+i2c_of_match_device_sysfs(const struct of_device_id *matches,
+ struct i2c_client *client)
+{
+ const char *name;
+
+ for (; matches->compatible[0]; matches++) {
+ /*
+ * Adding devices through the i2c sysfs interface provides us
+ * a string to match which may be compatible with the device
+ * tree compatible strings, however with no actual of_node the
+ * of_match_device() will not match
+ */
+ if (sysfs_streq(client->name, matches->compatible))
+ return matches;
+
+ name = strchr(matches->compatible, ',');
+ if (!name)
+ name = matches->compatible;
+ else
+ name++;
+
+ if (sysfs_streq(client->name, name))
+ return matches;
+ }
+
+ return NULL;
+}
+
+const struct of_device_id
+*i2c_of_match_device(const struct of_device_id *matches,
+ struct i2c_client *client)
+{
+ const struct of_device_id *match;
+
+ if (!(client && matches))
+ return NULL;
+
+ match = of_match_device(matches, &client->dev);
+ if (match)
+ return match;
+
+ return i2c_of_match_device_sysfs(matches, client);
+}
+EXPORT_SYMBOL_GPL(i2c_of_match_device);
+
+#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 */
+
+ 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);
+
+ if (IS_ERR(client)) {
+ dev_err(&adap->dev, "failed to create client for '%s'\n",
+ rd->dn->full_name);
+ of_node_clear_flag(rd->dn, OF_POPULATED);
+ return notifier_from_errno(PTR_ERR(client));
+ }
+ 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)
+ 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;
+}
+
+struct notifier_block i2c_of_notifier = {
+ .notifier_call = of_i2c_notify,
+};
+#endif /* CONFIG_OF_DYNAMIC */

Privacy Policy