Commit 3a89db5f authored by Jean Delvare's avatar Jean Delvare
Browse files

i2c: Check for address validity on client registration 



Do basic address validity checks when a client is being registered. We
already had checks in place for devices which are being detected, but
not for devices which are simply instantiated.

This is a very basic check. We don't want to do strict checking here
because some devices are known to infringe the I2C address constraints
(e.g. IR receivers at 7-bit address 0x7a while this value is
supposedly reserved for 10-bit addresses.) So we assume the caller
knows what it is doing.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Cc: Matthieu Castet <castet.matthieu@free.fr>
parent 63e4e802

drivers/i2c/i2c-core.c

+26 −7
Original line number Diff line number Diff line
@@ -371,6 +371,22 @@ struct i2c_client *i2c_verify_client(struct device *dev) 
EXPORT_SYMBOL(i2c_verify_client);





/* This is a permissive address validity check, I2C address map constraints

 * are purposedly not enforced, except for the general call address. */

static int i2c_check_client_addr_validity(const struct i2c_client *client)

{

	if (client->flags & I2C_CLIENT_TEN) {

		/* 10-bit address, all values are valid */

		if (client->addr > 0x3ff)

			return -EINVAL;

	} else {

		/* 7-bit address, reject the general call address */

		if (client->addr == 0x00 || client->addr > 0x7f)

			return -EINVAL;

	}

	return 0;

}



/**

 * i2c_new_device - instantiate an i2c device

 * @adap: the adapter managing the device
@@ -410,6 +426,14 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) 


	strlcpy(client->name, info->type, sizeof(client->name));



	/* Check for address validity */

	status = i2c_check_client_addr_validity(client);

	if (status) {

		dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n",

			client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr);

		goto out_err_silent;

	}



	/* Check for address business */

	status = i2c_check_addr(adap, client->addr);

	if (status)
@@ -436,6 +460,7 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) 
out_err:

	dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x "

		"(%d)\n", client->name, client->addr, status);

out_err_silent:

	kfree(client);

	return NULL;

}
@@ -561,15 +586,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, 
		return -EINVAL;

	}



	if (info.addr < 0x03 || info.addr > 0x77) {

		dev_err(dev, "%s: Invalid I2C address 0x%hx\n", "new_device",

			info.addr);

		return -EINVAL;

	}



	client = i2c_new_device(adap, &info);

	if (!client)

		return -EEXIST;

		return -EINVAL;



	/* Keep track of the added device */

	i2c_lock_adapter(adap);

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