Commit da899f55 authored by Wolfram Sang's avatar Wolfram Sang Committed by Wolfram Sang
Browse files

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: default avatarAndrey Danin <danindrey@mail.ru>
Acked-by: default avatarStephen Warren <swarren@nvidia.com>
Signed-off-by: default avatarWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent c5ebb387

drivers/i2c/i2c-core.c

+19 −3
Original line number Diff line number Diff line
@@ -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));

}



/**

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