i2c: Shrink struct i2c_client

This shrinks the size of "struct i2c_client" by 40 bytes:

 - Substantially shrinks the string used to identify the chip type
 - The "flags" don't need to be so big
 - Removes some internal padding

It also adds kerneldoc for that struct, explaining how "name" is really a
chip type identifier; it's otherwise potentially confusing.

Because the I2C_NAME_SIZE symbol was abused for both i2c_client.name
and for i2c_adapter.name, this needed to affect i2c_adapter too.  The
adapters which used that symbol now use the more-obviously-correct
idiom of taking the size of that field.

JD: Shorten i2c_adapter.name from 50 to 48 bytes while we're here, to
avoid wasting space in padding.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

3 files changed, 5 insertions, 4 deletions

diff --git a/drivers/media/dvb/b2c2/flexcop-i2c.c b/drivers/media/dvb/b2c2/flexcop-i2c.c
index 5347a406fff..02a0ea6e1c1 100644
--- a/drivers/media/dvb/b2c2/flexcop-i2c.c
+++ b/drivers/media/dvb/b2c2/flexcop-i2c.c
@@ -183,7 +183,8 @@ int flexcop_i2c_init(struct flexcop_device *fc)
 	mutex_init(&fc->i2c_mutex);
 
 	memset(&fc->i2c_adap, 0, sizeof(struct i2c_adapter));
-	strncpy(fc->i2c_adap.name, "B2C2 FlexCop device",I2C_NAME_SIZE);
+	strncpy(fc->i2c_adap.name, "B2C2 FlexCop device",
+		sizeof(fc->i2c_adap.name));
 
 	i2c_set_adapdata(&fc->i2c_adap,fc);
 
diff --git a/drivers/media/dvb/dvb-usb/dvb-usb-i2c.c b/drivers/media/dvb/dvb-usb/dvb-usb-i2c.c
index 70df31b0a8a..088b6dee3a7 100644
--- a/drivers/media/dvb/dvb-usb/dvb-usb-i2c.c
+++ b/drivers/media/dvb/dvb-usb/dvb-usb-i2c.c
@@ -19,7 +19,7 @@ int dvb_usb_i2c_init(struct dvb_usb_device *d)
 		return -EINVAL;
 	}
 
-	strncpy(d->i2c_adap.name,d->desc->name,I2C_NAME_SIZE);
+	strncpy(d->i2c_adap.name, d->desc->name, sizeof(d->i2c_adap.name));
 #ifdef I2C_ADAP_CLASS_TV_DIGITAL
 	d->i2c_adap.class = I2C_ADAP_CLASS_TV_DIGITAL,
 #else
diff --git a/drivers/media/dvb/frontends/dibx000_common.c b/drivers/media/dvb/frontends/dibx000_common.c
index a18c8f45a2e..315e09e95b0 100644
--- a/drivers/media/dvb/frontends/dibx000_common.c
+++ b/drivers/media/dvb/frontends/dibx000_common.c
@@ -105,9 +105,9 @@ struct i2c_adapter * dibx000_get_i2c_adapter(struct dibx000_i2c_master *mst, enu
 }
 EXPORT_SYMBOL(dibx000_get_i2c_adapter);
 
-static int i2c_adapter_init(struct i2c_adapter *i2c_adap, struct i2c_algorithm *algo, const char name[I2C_NAME_SIZE], struct dibx000_i2c_master *mst)
+static int i2c_adapter_init(struct i2c_adapter *i2c_adap, struct i2c_algorithm *algo, const char *name, struct dibx000_i2c_master *mst)
 {
-	strncpy(i2c_adap->name, name, I2C_NAME_SIZE);
+	strncpy(i2c_adap->name, name, sizeof(i2c_adap->name));
 	i2c_adap->class     = I2C_CLASS_TV_DIGITAL,
 	i2c_adap->algo      = algo;
 	i2c_adap->algo_data = NULL;