linux_dsm_epyc7002/include/linux/i2c-mux.h
Jean Delvare eee543e824 i2c-mux: Add support for device auto-detection
Let I2C bus segments behind multiplexers have a class. This allows for
device auto-detection on these segments. As long as parent segments
don't share the same class, it should be fine.

I implemented support in drivers i2c-mux-gpio and i2c-mux-pca954x. I
left i2c-mux-pca9541 and i2c-mux-pinctrl alone for the moment as I
don't know if this feature makes sense for the use cases of these
drivers.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
Cc: Rodolfo Giometti <giometti@linux.it>
2012-10-05 22:23:51 +02:00

50 lines
1.6 KiB
C

/*
*
* i2c-mux.h - functions for the i2c-bus mux support
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
* Michael Lawnick <michael.lawnick.ext@nsn.com>
*
* 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., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA.
*/
#ifndef _LINUX_I2C_MUX_H
#define _LINUX_I2C_MUX_H
#ifdef __KERNEL__
/*
* Called to create a i2c bus on a multiplexed bus segment.
* The mux_dev and chan_id parameters are passed to the select
* and deselect callback functions to perform hardware-specific
* mux control.
*/
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
struct device *mux_dev,
void *mux_priv, u32 force_nr, u32 chan_id,
unsigned int class,
int (*select) (struct i2c_adapter *,
void *mux_dev, u32 chan_id),
int (*deselect) (struct i2c_adapter *,
void *mux_dev, u32 chan_id));
int i2c_del_mux_adapter(struct i2c_adapter *adap);
#endif /* __KERNEL__ */
#endif /* _LINUX_I2C_MUX_H */