3f3a89e1d7
The i2c_lock_adapter name is ambiguous since it is unclear if it refers to the root adapter or the adapter you name in the argument. The natural interpretation is the adapter you name in the argument, but there are historical reasons for that not being the case; it in fact locks the root adapter. Just remove the function and force users to spell out the I2C_LOCK_ROOT_ADAPTER name to indicate what is really going on. Also remove i2c_unlock_adapter, of course. This patch was generated with git grep -l 'i2c_\(un\)\?lock_adapter' \ | xargs sed -i 's/i2c_\(un\)\?lock_adapter(\([^)]*\))/'\ 'i2c_\1lock_bus(\2, I2C_LOCK_ROOT_ADAPTER)/g' followed by white-space touch-up. Signed-off-by: Peter Rosin <peda@axentia.se> Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com> Tested-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
116 lines
3 KiB
C
116 lines
3 KiB
C
/*
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* Linux I2C core slave support code
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*
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* Copyright (C) 2014 by Wolfram Sang <wsa@sang-engineering.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the Free
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* Software Foundation; either version 2 of the License, or (at your option)
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* any later version.
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*/
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#include <dt-bindings/i2c/i2c.h>
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#include <linux/acpi.h>
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/i2c.h>
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#include <linux/of.h>
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#include "i2c-core.h"
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int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb)
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{
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int ret;
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if (!client || !slave_cb) {
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WARN(1, "insufficient data\n");
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return -EINVAL;
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}
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if (!(client->flags & I2C_CLIENT_SLAVE))
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dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n",
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__func__);
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if (!(client->flags & I2C_CLIENT_TEN)) {
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/* Enforce stricter address checking */
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ret = i2c_check_7bit_addr_validity_strict(client->addr);
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if (ret) {
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dev_err(&client->dev, "%s: invalid address\n", __func__);
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return ret;
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}
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}
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if (!client->adapter->algo->reg_slave) {
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dev_err(&client->dev, "%s: not supported by adapter\n", __func__);
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return -EOPNOTSUPP;
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}
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client->slave_cb = slave_cb;
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i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
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ret = client->adapter->algo->reg_slave(client);
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i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
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if (ret) {
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client->slave_cb = NULL;
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dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret);
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(i2c_slave_register);
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int i2c_slave_unregister(struct i2c_client *client)
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{
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int ret;
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if (!client->adapter->algo->unreg_slave) {
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dev_err(&client->dev, "%s: not supported by adapter\n", __func__);
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return -EOPNOTSUPP;
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}
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i2c_lock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
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ret = client->adapter->algo->unreg_slave(client);
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i2c_unlock_bus(client->adapter, I2C_LOCK_ROOT_ADAPTER);
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if (ret == 0)
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client->slave_cb = NULL;
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else
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dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret);
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return ret;
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}
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EXPORT_SYMBOL_GPL(i2c_slave_unregister);
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/**
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* i2c_detect_slave_mode - detect operation mode
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* @dev: The device owning the bus
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*
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* This checks the device nodes for an I2C slave by checking the address
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* used in the reg property. If the address match the I2C_OWN_SLAVE_ADDRESS
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* flag this means the device is configured to act as a I2C slave and it will
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* be listening at that address.
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*
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* Returns true if an I2C own slave address is detected, otherwise returns
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* false.
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*/
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bool i2c_detect_slave_mode(struct device *dev)
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{
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if (IS_BUILTIN(CONFIG_OF) && dev->of_node) {
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struct device_node *child;
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u32 reg;
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for_each_child_of_node(dev->of_node, child) {
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of_property_read_u32(child, "reg", ®);
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if (reg & I2C_OWN_SLAVE_ADDRESS) {
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of_node_put(child);
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return true;
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}
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}
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} else if (IS_BUILTIN(CONFIG_ACPI) && ACPI_HANDLE(dev)) {
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dev_dbg(dev, "ACPI slave is not supported yet\n");
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}
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return false;
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}
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EXPORT_SYMBOL_GPL(i2c_detect_slave_mode);
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