android_kernel_xiaomi_sm8350/drivers/i2c/i2c-core.h
Rodolfo Giometti f18c41daea i2c: Use rwsem instead of mutex for board info
By using rwsem we can easily manage recursive calls of
i2c_scan_static_board_info() function without breaking the locking.

Signed-off-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-06-19 16:58:20 +02:00

34 lines
1.1 KiB
C

/*
* i2c-core.h - interfaces internal to the I2C framework
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/rwsem.h>
struct i2c_devinfo {
struct list_head list;
int busnum;
struct i2c_board_info board_info;
};
/* board_lock protects board_list and first_dynamic_bus_num.
* only i2c core components are allowed to use these symbols.
*/
extern struct rw_semaphore __i2c_board_lock;
extern struct list_head __i2c_board_list;
extern int __i2c_first_dynamic_bus_num;