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i2c: apply address offset for slaves, too 

We want a separate address range for being an I2C slave. Add an offset
of 0x1000, so it can be combined with ten bit addresses as well. Add a
separate function to create the address value, we will need it later in
other places.

Tested-by: Andrey Danin <danindrey@mail.ru>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Wolfram Sang 2015-05-18 21:09:12 +02:00 committed by Wolfram Sang
parent c5ebb387f4
commit da899f55b3
1 changed files with 19 additions and 3 deletions
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22
drivers/i2c/i2c-core.c
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@ -57,6 +57,9 @@
#define CREATE_TRACE_POINTS
#include <trace/events/i2c.h>
#define I2C_ADDR_OFFSET_TEN_BIT 0xa000
#define I2C_ADDR_OFFSET_SLAVE 0x1000
/* core_lock protects i2c_adapter_idr, and guarantees
that device detection, deletion of detected devices, and attach_adapter
calls are serialized */
@ -778,6 +781,21 @@ struct i2c_client *i2c_verify_client(struct device *dev)
EXPORT_SYMBOL(i2c_verify_client);
/* Return a unique address which takes the flags of the client into account */
static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client)
{
unsigned short addr = client->addr;
/* For some client flags, add an arbitrary offset to avoid collisions */
if (client->flags & I2C_CLIENT_TEN)
addr |= I2C_ADDR_OFFSET_TEN_BIT;
if (client->flags & I2C_CLIENT_SLAVE)
addr |= I2C_ADDR_OFFSET_SLAVE;
return addr;
}
/* This is a permissive address validity check, I2C address map constraints
* are purposely not enforced, except for the general call address. */
static int i2c_check_client_addr_validity(const struct i2c_client *client)
@ -923,10 +941,8 @@ static void i2c_dev_set_name(struct i2c_adapter *adap,
return;
}
/* For 10-bit clients, add an arbitrary offset to avoid collisions */
dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap),
client->addr | ((client->flags & I2C_CLIENT_TEN)
? 0xa000 : 0));
i2c_encode_flags_to_addr(client));
}
/**