* [PATCH 2/4] i2c: Check for address validity on client registration
@ 2010-04-09 14:53 Jean Delvare
0 siblings, 0 replies; 2+ messages in thread
From: Jean Delvare @ 2010-04-09 14:53 UTC (permalink / raw)
To: Linux I2C, Matthieu Castet
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-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
Cc: Matthieu Castet <castet.matthieu-GANU6spQydw@public.gmane.org>
---
drivers/i2c/i2c-core.c | 33 ++++++++++++++++++++++++++-------
1 file changed, 26 insertions(+), 7 deletions(-)
--- linux-2.6.34-rc3.orig/drivers/i2c/i2c-core.c 2010-04-08 09:51:08.000000000 +0200
+++ linux-2.6.34-rc3/drivers/i2c/i2c-core.c 2010-04-08 15:01:31.000000000 +0200
@@ -372,6 +372,22 @@ struct i2c_client *i2c_verify_client(str
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
@@ -411,6 +427,14 @@ i2c_new_device(struct i2c_adapter *adap,
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 I2C address 0x%02hx\n",
+ client->addr);
+ goto out_err_silent;
+ }
+
/* Check for address business */
status = i2c_check_addr(adap, client->addr);
if (status)
@@ -434,6 +458,7 @@ i2c_new_device(struct i2c_adapter *adap,
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;
}
@@ -559,15 +584,9 @@ i2c_sysfs_new_device(struct device *dev,
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 */
mutex_lock(&core_lock);
--
Jean Delvare
^ permalink raw reply [flat|nested] 2+ messages in thread* [PATCH 0/4] Clean up address probing and validity checking code
@ 2010-05-31 11:22 Jean Delvare
[not found] ` <20100531132213.65f20b8f-ig7AzVSIIG7kN2dkZ6Wm7A@public.gmane.org>
0 siblings, 1 reply; 2+ messages in thread
From: Jean Delvare @ 2010-05-31 11:22 UTC (permalink / raw)
To: Linux I2C; +Cc: Matthieu Castet, Hans Verkuil
Here comes an update of the patchset I posted on April 9th, 2010. Now
applies cleanly on top of Linus' tree.
[PATCH 1/4] i2c: Share the I2C device presence detection code
[PATCH 2/4] i2c: Check for address validity on client registration
[PATCH 3/4] i2c: Document reserved I2C addresses
[PATCH 4/4] i2c: Rename i2c_check_addr to i2c_check_addr_busy
--
Jean Delvare
^ permalink raw reply [flat|nested] 2+ messages in thread
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2010-05-31 11:30 ` [PATCH 2/4] i2c: Check for address validity on client registration Jean Delvare
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