Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 127 insertions, 0 deletions

diff --git a/drivers/i2c/i2c-core-slave.c b/drivers/i2c/i2c-core-slave.c
new file mode 100644
index 000000000..e3765e12f
--- /dev/null
+++ b/drivers/i2c/i2c-core-slave.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Linux I2C core slave support code
+ *
+ * Copyright (C) 2014 by Wolfram Sang <wsa@sang-engineering.com>
+ */
+
+#include <dt-bindings/i2c/i2c.h>
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/of.h>
+
+#include "i2c-core.h"
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/i2c_slave.h>
+
+int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb)
+{
+	int ret;
+
+	if (WARN(IS_ERR_OR_NULL(client) || !slave_cb, "insufficient data\n"))
+		return -EINVAL;
+
+	if (!(client->flags & I2C_CLIENT_SLAVE))
+		dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n",
+			 __func__);
+
+	if (!(client->flags & I2C_CLIENT_TEN)) {
+		/* Enforce stricter address checking */
+		ret = i2c_check_7bit_addr_validity_strict(client->addr);
+		if (ret) {
+			dev_err(&client->dev, "%s: invalid address\n", __func__);
+			return ret;
+		}
+	}
+
+	if (!client->adapter->algo->reg_slave) {
+		dev_err(&client->dev, "%s: not supported by adapter\n", __func__);
+		return -EOPNOTSUPP;
+	}
+
+	client->slave_cb = slave_cb;
+
+	i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
+	ret = client->adapter->algo->reg_slave(client);
+	i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
+
+	if (ret) {
+		client->slave_cb = NULL;
+		dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(i2c_slave_register);
+
+int i2c_slave_unregister(struct i2c_client *client)
+{
+	int ret;
+
+	if (IS_ERR_OR_NULL(client))
+		return -EINVAL;
+
+	if (!client->adapter->algo->unreg_slave) {
+		dev_err(&client->dev, "%s: not supported by adapter\n", __func__);
+		return -EOPNOTSUPP;
+	}
+
+	i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
+	ret = client->adapter->algo->unreg_slave(client);
+	i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
+
+	if (ret == 0)
+		client->slave_cb = NULL;
+	else
+		dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(i2c_slave_unregister);
+
+int i2c_slave_event(struct i2c_client *client,
+		    enum i2c_slave_event event, u8 *val)
+{
+	int ret = client->slave_cb(client, event, val);
+
+	if (trace_i2c_slave_enabled())
+		trace_i2c_slave(client, event, val, ret);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(i2c_slave_event);
+
+/**
+ * i2c_detect_slave_mode - detect operation mode
+ * @dev: The device owning the bus
+ *
+ * This checks the device nodes for an I2C slave by checking the address
+ * used in the reg property. If the address match the I2C_OWN_SLAVE_ADDRESS
+ * flag this means the device is configured to act as a I2C slave and it will
+ * be listening at that address.
+ *
+ * Returns true if an I2C own slave address is detected, otherwise returns
+ * false.
+ */
+bool i2c_detect_slave_mode(struct device *dev)
+{
+	if (IS_BUILTIN(CONFIG_OF) && dev->of_node) {
+		struct device_node *child;
+		u32 reg;
+
+		for_each_child_of_node(dev->of_node, child) {
+			of_property_read_u32(child, "reg", &reg);
+			if (reg & I2C_OWN_SLAVE_ADDRESS) {
+				of_node_put(child);
+				return true;
+			}
+		}
+	} else if (IS_BUILTIN(CONFIG_ACPI) && ACPI_HANDLE(dev)) {
+		dev_dbg(dev, "ACPI slave is not supported yet\n");
+	}
+	return false;
+}
+EXPORT_SYMBOL_GPL(i2c_detect_slave_mode);