Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cf02df77 authored by Jean Delvare's avatar Jean Delvare Committed by Greg Kroah-Hartman
Browse files

[PATCH] i2c: Rework client usage count, 3 of 3 



Do not limit the usage count of i2c clients to 1. In other words,
change the client usage count behavior from the old I2C_CLIENT_ALLOW_USE
to the old I2C_CLIENT_ALLOW_MULTIPLE_USE. The rationale is that no
driver actually needs the limiting behavior, and the unlimiting
behavior is slightly easier to implement.

Update the documentation to reflect this change.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent cde7859b

Documentation/i2c/porting-clients

+1 −0
Original line number Diff line number Diff line
@@ -92,6 +92,7 @@ Technical changes: 
  Drop client->id.

  Drop any 24RF08 corruption prevention you find, as this is now done

  at the i2c-core level, and doing it twice voids it.

  Don't add I2C_CLIENT_ALLOW_USE to client->flags, it's the default now.



* [Init] Limits must not be set by the driver (can be done later in

  user-space). Chip should not be reset default (although a module

drivers/i2c/i2c-core.c

+0 −5
Original line number Diff line number Diff line
@@ -497,14 +497,9 @@ int i2c_use_client(struct i2c_client *client) 
	if (ret)

		return ret;



	if (client->usage_count > 0)

		goto busy;

	client->usage_count++;



	return 0;

 busy:

	i2c_dec_use_client(client);

	return -EBUSY;

}



int i2c_release_client(struct i2c_client *client)

include/linux/i2c.h

+1 −3
Original line number Diff line number Diff line
@@ -307,9 +307,7 @@ extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id, 
   extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);

   to make sure that client-struct is valid and that it is okay to access

   the i2c-client. 

   returns -EACCES if client doesn't allow use (default)

   returns -EBUSY if client doesn't allow multiple use (default) and 

   usage_count >0 */

   returns -ENODEV if client has gone in the meantime */

extern int i2c_use_client(struct i2c_client *);

extern int i2c_release_client(struct i2c_client *);