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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: Jean Delvare <khali@linux-fr.org>
Cc: Matthieu Castet <castet.matthieu@free.fr>
This commit is contained in:
Jean Delvare 2010-06-03 11:33:52 +02:00
parent 63e4e80218
commit 3a89db5f30
1 changed files with 26 additions and 7 deletions
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33
drivers/i2c/i2c-core.c
View File

@ -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);