1 files changed, 528 insertions, 124 deletions

diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index e388590b44a..7c7f4b856ba 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -21,39 +21,62 @@
 /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
    All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
    SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
-   Jean Delvare <khali@linux-fr.org>
+   Jean Delvare <jdelvare@suse.de>
    Mux support by Rodolfo Giometti <giometti@enneenne.com> and
-   Michael Lawnick <michael.lawnick.ext@nsn.com> */
+   Michael Lawnick <michael.lawnick.ext@nsn.com>
+   OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
+   (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and
+   (c) 2013  Wolfram Sang <wsa@the-dreams.de>
+ */
 
 #include <linux/module.h>
 #include <linux/kernel.h>
+#include <linux/delay.h>
 #include <linux/errno.h>
+#include <linux/gpio.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
 #include <linux/idr.h>
 #include <linux/mutex.h>
+#include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_irq.h>
 #include <linux/completion.h>
 #include <linux/hardirq.h>
 #include <linux/irqflags.h>
 #include <linux/rwsem.h>
 #include <linux/pm_runtime.h>
 #include <linux/acpi.h>
+#include <linux/jump_label.h>
 #include <asm/uaccess.h>
 
 #include "i2c-core.h"
 
+#define CREATE_TRACE_POINTS
+#include <trace/events/i2c.h>
 
 /* core_lock protects i2c_adapter_idr, and guarantees
    that device detection, deletion of detected devices, and attach_adapter
-   and detach_adapter calls are serialized */
+   calls are serialized */
 static DEFINE_MUTEX(core_lock);
 static DEFINE_IDR(i2c_adapter_idr);
 
 static struct device_type i2c_client_type;
 static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver);
 
+static struct static_key i2c_trace_msg = STATIC_KEY_INIT_FALSE;
+
+void i2c_transfer_trace_reg(void)
+{
+	static_key_slow_inc(&i2c_trace_msg);
+}
+
+void i2c_transfer_trace_unreg(void)
+{
+	static_key_slow_dec(&i2c_trace_msg);
+}
+
 /* ------------------------------------------------------------------------- */
 
 static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
@@ -91,12 +114,16 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
 	return 0;
 }
 
-#ifdef	CONFIG_HOTPLUG
 
 /* uevent helps with hotplug: modprobe -q $(MODALIAS) */
 static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
 	struct i2c_client	*client = to_i2c_client(dev);
+	int rc;
+
+	rc = acpi_device_uevent_modalias(dev, env);
+	if (rc != -ENODEV)
+		return rc;
 
 	if (add_uevent_var(env, "MODALIAS=%s%s",
 			   I2C_MODULE_PREFIX, client->name))
@@ -105,9 +132,129 @@ static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env)
 	return 0;
 }
 
-#else
-#define i2c_device_uevent	NULL
-#endif	/* CONFIG_HOTPLUG */
+/* i2c bus recovery routines */
+static int get_scl_gpio_value(struct i2c_adapter *adap)
+{
+	return gpio_get_value(adap->bus_recovery_info->scl_gpio);
+}
+
+static void set_scl_gpio_value(struct i2c_adapter *adap, int val)
+{
+	gpio_set_value(adap->bus_recovery_info->scl_gpio, val);
+}
+
+static int get_sda_gpio_value(struct i2c_adapter *adap)
+{
+	return gpio_get_value(adap->bus_recovery_info->sda_gpio);
+}
+
+static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap)
+{
+	struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+	struct device *dev = &adap->dev;
+	int ret = 0;
+
+	ret = gpio_request_one(bri->scl_gpio, GPIOF_OPEN_DRAIN |
+			GPIOF_OUT_INIT_HIGH, "i2c-scl");
+	if (ret) {
+		dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio);
+		return ret;
+	}
+
+	if (bri->get_sda) {
+		if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) {
+			/* work without SDA polling */
+			dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n",
+					bri->sda_gpio);
+			bri->get_sda = NULL;
+		}
+	}
+
+	return ret;
+}
+
+static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap)
+{
+	struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+
+	if (bri->get_sda)
+		gpio_free(bri->sda_gpio);
+
+	gpio_free(bri->scl_gpio);
+}
+
+/*
+ * We are generating clock pulses. ndelay() determines durating of clk pulses.
+ * We will generate clock with rate 100 KHz and so duration of both clock levels
+ * is: delay in ns = (10^6 / 100) / 2
+ */
+#define RECOVERY_NDELAY		5000
+#define RECOVERY_CLK_CNT	9
+
+static int i2c_generic_recovery(struct i2c_adapter *adap)
+{
+	struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+	int i = 0, val = 1, ret = 0;
+
+	if (bri->prepare_recovery)
+		bri->prepare_recovery(bri);
+
+	/*
+	 * By this time SCL is high, as we need to give 9 falling-rising edges
+	 */
+	while (i++ < RECOVERY_CLK_CNT * 2) {
+		if (val) {
+			/* Break if SDA is high */
+			if (bri->get_sda && bri->get_sda(adap))
+					break;
+			/* SCL shouldn't be low here */
+			if (!bri->get_scl(adap)) {
+				dev_err(&adap->dev,
+					"SCL is stuck low, exit recovery\n");
+				ret = -EBUSY;
+				break;
+			}
+		}
+
+		val = !val;
+		bri->set_scl(adap, val);
+		ndelay(RECOVERY_NDELAY);
+	}
+
+	if (bri->unprepare_recovery)
+		bri->unprepare_recovery(bri);
+
+	return ret;
+}
+
+int i2c_generic_scl_recovery(struct i2c_adapter *adap)
+{
+	adap->bus_recovery_info->set_scl(adap, 1);
+	return i2c_generic_recovery(adap);
+}
+
+int i2c_generic_gpio_recovery(struct i2c_adapter *adap)
+{
+	int ret;
+
+	ret = i2c_get_gpios_for_recovery(adap);
+	if (ret)
+		return ret;
+
+	ret = i2c_generic_recovery(adap);
+	i2c_put_gpios_for_recovery(adap);
+
+	return ret;
+}
+
+int i2c_recover_bus(struct i2c_adapter *adap)
+{
+	if (!adap->bus_recovery_info)
+		return -EOPNOTSUPP;
+
+	dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
+	return adap->bus_recovery_info->recover_bus(adap);
+}
 
 static int i2c_device_probe(struct device *dev)
 {
@@ -121,17 +268,17 @@ static int i2c_device_probe(struct device *dev)
 	driver = to_i2c_driver(dev->driver);
 	if (!driver->probe || !driver->id_table)
 		return -ENODEV;
-	client->driver = driver;
+
 	if (!device_can_wakeup(&client->dev))
 		device_init_wakeup(&client->dev,
 					client->flags & I2C_CLIENT_WAKE);
 	dev_dbg(dev, "probe\n");
 
+	acpi_dev_pm_attach(&client->dev, true);
 	status = driver->probe(client, i2c_match_id(driver->id_table, client));
-	if (status) {
-		client->driver = NULL;
-		i2c_set_clientdata(client, NULL);
-	}
+	if (status)
+		acpi_dev_pm_detach(&client->dev, true);
+
 	return status;
 }
 
@@ -139,7 +286,7 @@ static int i2c_device_remove(struct device *dev)
 {
 	struct i2c_client	*client = i2c_verify_client(dev);
 	struct i2c_driver	*driver;
-	int			status;
+	int status = 0;
 
 	if (!client || !dev->driver)
 		return 0;
@@ -148,14 +295,9 @@ static int i2c_device_remove(struct device *dev)
 	if (driver->remove) {
 		dev_dbg(dev, "remove\n");
 		status = driver->remove(client);
-	} else {
-		dev->driver = NULL;
-		status = 0;
-	}
-	if (status == 0) {
-		client->driver = NULL;
-		i2c_set_clientdata(client, NULL);
 	}
+
+	acpi_dev_pm_detach(&client->dev, true);
 	return status;
 }
 
@@ -282,6 +424,12 @@ static ssize_t
 show_modalias(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct i2c_client *client = to_i2c_client(dev);
+	int len;
+
+	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
+	if (len != -ENODEV)
+		return len;
+
 	return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name);
 }
 
@@ -314,7 +462,7 @@ static const struct dev_pm_ops i2c_device_pm_ops = {
 	SET_RUNTIME_PM_OPS(
 		pm_generic_runtime_suspend,
 		pm_generic_runtime_resume,
-		pm_generic_runtime_idle
+		NULL
 	)
 };
 
@@ -488,6 +636,22 @@ void i2c_unlock_adapter(struct i2c_adapter *adapter)
 }
 EXPORT_SYMBOL_GPL(i2c_unlock_adapter);
 
+static void i2c_dev_set_name(struct i2c_adapter *adap,
+			     struct i2c_client *client)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&client->dev);
+
+	if (adev) {
+		dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev));
+		return;
+	}
+
+	/* For 10-bit clients, add an arbitrary offset to avoid collisions */
+	dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap),
+		     client->addr | ((client->flags & I2C_CLIENT_TEN)
+				     ? 0xa000 : 0));
+}
+
 /**
  * i2c_new_device - instantiate an i2c device
  * @adap: the adapter managing the device
@@ -544,12 +708,9 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
 	client->dev.bus = &i2c_bus_type;
 	client->dev.type = &i2c_client_type;
 	client->dev.of_node = info->of_node;
-	ACPI_HANDLE_SET(&client->dev, info->acpi_node.handle);
+	ACPI_COMPANION_SET(&client->dev, info->acpi_node.companion);
 
-	/* For 10-bit clients, add an arbitrary offset to avoid collisions */
-	dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap),
-		     client->addr | ((client->flags & I2C_CLIENT_TEN)
-				     ? 0xa000 : 0));
+	i2c_dev_set_name(adap, client);
 	status = device_register(&client->dev);
 	if (status)
 		goto out_err;
@@ -771,7 +932,8 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
 }
 
 static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device);
-static DEVICE_ATTR(delete_device, S_IWUSR, NULL, i2c_sysfs_delete_device);
+static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL,
+				   i2c_sysfs_delete_device);
 
 static struct attribute *i2c_adapter_attrs[] = {
 	&dev_attr_name.attr,
@@ -832,6 +994,199 @@ static void i2c_scan_static_board_info(struct i2c_adapter *adapter)
 	up_read(&__i2c_board_lock);
 }
 
+/* OF support code */
+
+#if IS_ENABLED(CONFIG_OF)
+static void of_i2c_register_devices(struct i2c_adapter *adap)
+{
+	void *result;
+	struct device_node *node;
+
+	/* 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");
+
+	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;
+
+		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);
+			continue;
+		}
+
+		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;
+		}
+
+		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;
+		}
+
+		info.irq = irq_of_parse_and_map(node, 0);
+		info.of_node = of_node_get(node);
+		info.archdata = &dev_ad;
+
+		if (of_get_property(node, "wakeup-source", NULL))
+			info.flags |= I2C_CLIENT_WAKE;
+
+		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);
+			continue;
+		}
+	}
+}
+
+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;
+
+	dev = bus_find_device(&i2c_bus_type, NULL, node,
+					 of_dev_node_match);
+	if (!dev)
+		return NULL;
+
+	return i2c_verify_client(dev);
+}
+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;
+
+	dev = bus_find_device(&i2c_bus_type, NULL, node,
+					 of_dev_node_match);
+	if (!dev)
+		return NULL;
+
+	return i2c_verify_adapter(dev);
+}
+EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
+#else
+static void of_i2c_register_devices(struct i2c_adapter *adap) { }
+#endif /* CONFIG_OF */
+
+/* ACPI support code */
+
+#if IS_ENABLED(CONFIG_ACPI)
+static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
+{
+	struct i2c_board_info *info = data;
+
+	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+		struct acpi_resource_i2c_serialbus *sb;
+
+		sb = &ares->data.i2c_serial_bus;
+		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+			info->addr = sb->slave_address;
+			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+				info->flags |= I2C_CLIENT_TEN;
+		}
+	} else if (info->irq < 0) {
+		struct resource r;
+
+		if (acpi_dev_resource_interrupt(ares, 0, &r))
+			info->irq = r.start;
+	}
+
+	/* Tell the ACPI core to skip this resource */
+	return 1;
+}
+
+static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
+				       void *data, void **return_value)
+{
+	struct i2c_adapter *adapter = data;
+	struct list_head resource_list;
+	struct i2c_board_info info;
+	struct acpi_device *adev;
+	int ret;
+
+	if (acpi_bus_get_device(handle, &adev))
+		return AE_OK;
+	if (acpi_bus_get_status(adev) || !adev->status.present)
+		return AE_OK;
+
+	memset(&info, 0, sizeof(info));
+	info.acpi_node.companion = adev;
+	info.irq = -1;
+
+	INIT_LIST_HEAD(&resource_list);
+	ret = acpi_dev_get_resources(adev, &resource_list,
+				     acpi_i2c_add_resource, &info);
+	acpi_dev_free_resource_list(&resource_list);
+
+	if (ret < 0 || !info.addr)
+		return AE_OK;
+
+	adev->power.flags.ignore_parent = true;
+	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
+	if (!i2c_new_device(adapter, &info)) {
+		adev->power.flags.ignore_parent = false;
+		dev_err(&adapter->dev,
+			"failed to add I2C device %s from ACPI\n",
+			dev_name(&adev->dev));
+	}
+
+	return AE_OK;
+}
+
+/**
+ * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
+ * @adap: pointer to adapter
+ *
+ * Enumerate all I2C slave devices behind this adapter by walking the ACPI
+ * namespace. When a device is found it will be added to the Linux device
+ * model and bound to the corresponding ACPI handle.
+ */
+static void acpi_i2c_register_devices(struct i2c_adapter *adap)
+{
+	acpi_handle handle;
+	acpi_status status;
+
+	if (!adap->dev.parent)
+		return;
+
+	handle = ACPI_HANDLE(adap->dev.parent);
+	if (!handle)
+		return;
+
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+				     acpi_i2c_add_device, NULL,
+				     adap, NULL);
+	if (ACPI_FAILURE(status))
+		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
+}
+#else
+static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) {}
+#endif /* CONFIG_ACPI */
+
 static int i2c_do_add_adapter(struct i2c_driver *driver,
 			      struct i2c_adapter *adap)
 {
@@ -902,7 +1257,43 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
 			 "Failed to create compatibility class link\n");
 #endif
 
+	/* bus recovery specific initialization */
+	if (adap->bus_recovery_info) {
+		struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+
+		if (!bri->recover_bus) {
+			dev_err(&adap->dev, "No recover_bus() found, not using recovery\n");
+			adap->bus_recovery_info = NULL;
+			goto exit_recovery;
+		}
+
+		/* Generic GPIO recovery */
+		if (bri->recover_bus == i2c_generic_gpio_recovery) {
+			if (!gpio_is_valid(bri->scl_gpio)) {
+				dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n");
+				adap->bus_recovery_info = NULL;
+				goto exit_recovery;
+			}
+
+			if (gpio_is_valid(bri->sda_gpio))
+				bri->get_sda = get_sda_gpio_value;
+			else
+				bri->get_sda = NULL;
+
+			bri->get_scl = get_scl_gpio_value;
+			bri->set_scl = set_scl_gpio_value;
+		} else if (!bri->set_scl || !bri->get_scl) {
+			/* Generic SCL recovery */
+			dev_err(&adap->dev, "No {get|set}_gpio() found, not using recovery\n");
+			adap->bus_recovery_info = NULL;
+		}
+	}
+
+exit_recovery:
 	/* create pre-declared device nodes */
+	of_i2c_register_devices(adap);
+	acpi_i2c_register_devices(adap);
+
 	if (adap->nr < __i2c_first_dynamic_bus_num)
 		i2c_scan_static_board_info(adap);
 
@@ -921,13 +1312,35 @@ out_list:
 }
 
 /**
+ * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1
+ * @adap: the adapter to register (with adap->nr initialized)
+ * Context: can sleep
+ *
+ * See i2c_add_numbered_adapter() for details.
+ */
+static int __i2c_add_numbered_adapter(struct i2c_adapter *adap)
+{
+	int	id;
+
+	mutex_lock(&core_lock);
+	id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1,
+		       GFP_KERNEL);
+	mutex_unlock(&core_lock);
+	if (id < 0)
+		return id == -ENOSPC ? -EBUSY : id;
+
+	return i2c_register_adapter(adap);
+}
+
+/**
  * i2c_add_adapter - declare i2c adapter, use dynamic bus number
  * @adapter: the adapter to add
  * Context: can sleep
  *
  * This routine is used to declare an I2C adapter when its bus number
- * doesn't matter.  Examples: for I2C adapters dynamically added by
- * USB links or PCI plugin cards.
+ * doesn't matter or when its bus number is specified by an dt alias.
+ * Examples of bases when the bus number doesn't matter: I2C adapters
+ * dynamically added by USB links or PCI plugin cards.
  *
  * When this returns zero, a new bus number was allocated and stored
  * in adap->nr, and the specified adapter became available for clients.
@@ -935,25 +1348,26 @@ out_list:
  */
 int i2c_add_adapter(struct i2c_adapter *adapter)
 {
-	int	id, res = 0;
+	struct device *dev = &adapter->dev;
+	int id;
 
-retry:
-	if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0)
-		return -ENOMEM;
+	if (dev->of_node) {
+		id = of_alias_get_id(dev->of_node, "i2c");
+		if (id >= 0) {
+			adapter->nr = id;
+			return __i2c_add_numbered_adapter(adapter);
+		}
+	}
 
 	mutex_lock(&core_lock);
-	/* "above" here means "above or equal to", sigh */
-	res = idr_get_new_above(&i2c_adapter_idr, adapter,
-				__i2c_first_dynamic_bus_num, &id);
+	id = idr_alloc(&i2c_adapter_idr, adapter,
+		       __i2c_first_dynamic_bus_num, 0, GFP_KERNEL);
 	mutex_unlock(&core_lock);
-
-	if (res < 0) {
-		if (res == -EAGAIN)
-			goto retry;
-		return res;
-	}
+	if (id < 0)
+		return id;
 
 	adapter->nr = id;
+
 	return i2c_register_adapter(adapter);
 }
 EXPORT_SYMBOL(i2c_add_adapter);
@@ -983,42 +1397,17 @@ EXPORT_SYMBOL(i2c_add_adapter);
  */
 int i2c_add_numbered_adapter(struct i2c_adapter *adap)
 {
-	int	id;
-	int	status;
-
 	if (adap->nr == -1) /* -1 means dynamically assign bus id */
 		return i2c_add_adapter(adap);
-	if (adap->nr & ~MAX_IDR_MASK)
-		return -EINVAL;
-
-retry:
-	if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0)
-		return -ENOMEM;
 
-	mutex_lock(&core_lock);
-	/* "above" here means "above or equal to", sigh;
-	 * we need the "equal to" result to force the result
-	 */
-	status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id);
-	if (status == 0 && id != adap->nr) {
-		status = -EBUSY;
-		idr_remove(&i2c_adapter_idr, id);
-	}
-	mutex_unlock(&core_lock);
-	if (status == -EAGAIN)
-		goto retry;
-
-	if (status == 0)
-		status = i2c_register_adapter(adap);
-	return status;
+	return __i2c_add_numbered_adapter(adap);
 }
 EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter);
 
-static int i2c_do_del_adapter(struct i2c_driver *driver,
+static void i2c_do_del_adapter(struct i2c_driver *driver,
 			      struct i2c_adapter *adapter)
 {
 	struct i2c_client *client, *_n;
-	int res;
 
 	/* Remove the devices we created ourselves as the result of hardware
 	 * probing (using a driver's detect method) */
@@ -1030,16 +1419,6 @@ static int i2c_do_del_adapter(struct i2c_driver *driver,
 			i2c_unregister_device(client);
 		}
 	}
-
-	if (!driver->detach_adapter)
-		return 0;
-	dev_warn(&adapter->dev, "%s: detach_adapter method is deprecated\n",
-		 driver->driver.name);
-	res = driver->detach_adapter(adapter);
-	if (res)
-		dev_err(&adapter->dev, "detach_adapter failed (%d) "
-			"for driver [%s]\n", res, driver->driver.name);
-	return res;
 }
 
 static int __unregister_client(struct device *dev, void *dummy)
@@ -1060,7 +1439,8 @@ static int __unregister_dummy(struct device *dev, void *dummy)
 
 static int __process_removed_adapter(struct device_driver *d, void *data)
 {
-	return i2c_do_del_adapter(to_i2c_driver(d), data);
+	i2c_do_del_adapter(to_i2c_driver(d), data);
+	return 0;
 }
 
 /**
@@ -1071,9 +1451,8 @@ static int __process_removed_adapter(struct device_driver *d, void *data)
  * This unregisters an I2C adapter which was previously registered
  * by @i2c_add_adapter or @i2c_add_numbered_adapter.
  */
-int i2c_del_adapter(struct i2c_adapter *adap)
+void i2c_del_adapter(struct i2c_adapter *adap)
 {
-	int res = 0;
 	struct i2c_adapter *found;
 	struct i2c_client *client, *next;
 
@@ -1084,16 +1463,14 @@ int i2c_del_adapter(struct i2c_adapter *adap)
 	if (found != adap) {
 		pr_debug("i2c-core: attempting to delete unregistered "
 			 "adapter [%s]\n", adap->name);
-		return -EINVAL;
+		return;
 	}
 
 	/* Tell drivers about this removal */
 	mutex_lock(&core_lock);
-	res = bus_for_each_drv(&i2c_bus_type, NULL, adap,
+	bus_for_each_drv(&i2c_bus_type, NULL, adap,
 			       __process_removed_adapter);
 	mutex_unlock(&core_lock);
-	if (res)
-		return res;
 
 	/* Remove devices instantiated from sysfs */
 	mutex_lock_nested(&adap->userspace_clients_lock,
@@ -1112,8 +1489,8 @@ int i2c_del_adapter(struct i2c_adapter *adap)
 	 * we can't remove the dummy devices during the first pass: they
 	 * could have been instantiated by real devices wishing to clean
 	 * them up properly, so we give them a chance to do that first. */
-	res = device_for_each_child(&adap->dev, NULL, __unregister_client);
-	res = device_for_each_child(&adap->dev, NULL, __unregister_dummy);
+	device_for_each_child(&adap->dev, NULL, __unregister_client);
+	device_for_each_child(&adap->dev, NULL, __unregister_dummy);
 
 #ifdef CONFIG_I2C_COMPAT
 	class_compat_remove_link(i2c_adapter_compat_class, &adap->dev,
@@ -1138,12 +1515,9 @@ int i2c_del_adapter(struct i2c_adapter *adap)
 	/* Clear the device structure in case this adapter is ever going to be
 	   added again */
 	memset(&adap->dev, 0, sizeof(adap->dev));
-
-	return 0;
 }
 EXPORT_SYMBOL(i2c_del_adapter);
 
-
 /* ------------------------------------------------------------------------- */
 
 int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *))
@@ -1209,9 +1583,9 @@ EXPORT_SYMBOL(i2c_register_driver);
 
 static int __process_removed_driver(struct device *dev, void *data)
 {
-	if (dev->type != &i2c_adapter_type)
-		return 0;
-	return i2c_do_del_adapter(data, to_i2c_adapter(dev));
+	if (dev->type == &i2c_adapter_type)
+		i2c_do_del_adapter(data, to_i2c_adapter(dev));
+	return 0;
 }
 
 /**
@@ -1271,9 +1645,14 @@ static int i2c_cmd(struct device *dev, void *_arg)
 {
 	struct i2c_client	*client = i2c_verify_client(dev);
 	struct i2c_cmd_arg	*arg = _arg;
+	struct i2c_driver	*driver;
+
+	if (!client || !client->dev.driver)
+		return 0;
 
-	if (client && client->driver && client->driver->command)
-		client->driver->command(client, arg->cmd, arg->arg);
+	driver = to_i2c_driver(client->dev.driver);
+	if (driver->command)
+		driver->command(client, arg->cmd, arg->arg);
 	return 0;
 }
 
@@ -1322,6 +1701,7 @@ static void __exit i2c_exit(void)
 	class_compat_unregister(i2c_adapter_compat_class);
 #endif
 	bus_unregister(&i2c_bus_type);
+	tracepoint_synchronize_unregister();
 }
 
 /* We must initialize early, because some subsystems register i2c drivers
@@ -1352,6 +1732,19 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 	unsigned long orig_jiffies;
 	int ret, try;
 
+	/* i2c_trace_msg gets enabled when tracepoint i2c_transfer gets
+	 * enabled.  This is an efficient way of keeping the for-loop from
+	 * being executed when not needed.
+	 */
+	if (static_key_false(&i2c_trace_msg)) {
+		int i;
+		for (i = 0; i < num; i++)
+			if (msgs[i].flags & I2C_M_RD)
+				trace_i2c_read(adap, &msgs[i], i);
+			else
+				trace_i2c_write(adap, &msgs[i], i);
+	}
+
 	/* Retry automatically on arbitration loss */
 	orig_jiffies = jiffies;
 	for (ret = 0, try = 0; try <= adap->retries; try++) {
@@ -1362,6 +1755,14 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 			break;
 	}
 
+	if (static_key_false(&i2c_trace_msg)) {
+		int i;
+		for (i = 0; i < ret; i++)
+			if (msgs[i].flags & I2C_M_RD)
+				trace_i2c_reply(adap, &msgs[i], i);
+		trace_i2c_result(adap, i, ret);
+	}
+
 	return ret;
 }
 EXPORT_SYMBOL(__i2c_transfer);
@@ -1526,7 +1927,8 @@ static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr)
 		err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
 				     I2C_SMBUS_BYTE, &dummy);
 	else {
-		dev_warn(&adap->dev, "No suitable probing method supported\n");
+		dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n",
+			 addr);
 		err = -EOPNOTSUPP;
 	}
 
@@ -1576,6 +1978,13 @@ static int i2c_detect_address(struct i2c_client *temp_client,
 		struct i2c_client *client;
 
 		/* Detection succeeded, instantiate the device */
+		if (adapter->class & I2C_CLASS_DEPRECATED)
+			dev_warn(&adapter->dev,
+				"This adapter will soon drop class based instantiation of devices. "
+				"Please make sure client 0x%02x gets instantiated by other means. "
+				"Check 'Documentation/i2c/instantiating-devices' for details.\n",
+				info.addr);
+
 		dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n",
 			info.type, info.addr);
 		client = i2c_new_device(adapter, &info);
@@ -1686,7 +2095,8 @@ EXPORT_SYMBOL(i2c_get_adapter);
 
 void i2c_put_adapter(struct i2c_adapter *adap)
 {
-	module_put(adap->owner);
+	if (adap)
+		module_put(adap->owner);
 }
 EXPORT_SYMBOL(i2c_put_adapter);
 
@@ -1866,29 +2276,6 @@ s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command,
 EXPORT_SYMBOL(i2c_smbus_write_word_data);
 
 /**
- * i2c_smbus_process_call - SMBus "process call" protocol
- * @client: Handle to slave device
- * @command: Byte interpreted by slave
- * @value: 16-bit "word" being written
- *
- * This executes the SMBus "process call" protocol, returning negative errno
- * else a 16-bit unsigned "word" received from the device.
- */
-s32 i2c_smbus_process_call(const struct i2c_client *client, u8 command,
-			   u16 value)
-{
-	union i2c_smbus_data data;
-	int status;
-	data.word = value;
-
-	status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
-				I2C_SMBUS_WRITE, command,
-				I2C_SMBUS_PROC_CALL, &data);
-	return (status < 0) ? status : data.word;
-}
-EXPORT_SYMBOL(i2c_smbus_process_call);
-
-/**
  * i2c_smbus_read_block_data - SMBus "block read" protocol
  * @client: Handle to slave device
  * @command: Byte interpreted by slave
@@ -2178,6 +2565,14 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
 	int try;
 	s32 res;
 
+	/* If enabled, the following two tracepoints are conditional on
+	 * read_write and protocol.
+	 */
+	trace_smbus_write(adapter, addr, flags, read_write,
+			  command, protocol, data);
+	trace_smbus_read(adapter, addr, flags, read_write,
+			 command, protocol);
+
 	flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB;
 
 	if (adapter->algo->smbus_xfer) {
@@ -2198,15 +2593,24 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
 		i2c_unlock_adapter(adapter);
 
 		if (res != -EOPNOTSUPP || !adapter->algo->master_xfer)
-			return res;
+			goto trace;
 		/*
 		 * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't
 		 * implement native support for the SMBus operation.
 		 */
 	}
 
-	return i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
-				       command, protocol, data);
+	res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
+				      command, protocol, data);
+
+trace:
+	/* If enabled, the reply tracepoint is conditional on read_write. */
+	trace_smbus_reply(adapter, addr, flags, read_write,
+			  command, protocol, data);
+	trace_smbus_result(adapter, addr, flags, read_write,
+			   command, protocol, res);
+
+	return res;
 }
 EXPORT_SYMBOL(i2c_smbus_xfer);