diff options
Diffstat (limited to 'include/linux/i2c-mux.h')
| -rw-r--r-- | include/linux/i2c-mux.h | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h new file mode 100644 index 000000000..98ef73b7c --- /dev/null +++ b/include/linux/i2c-mux.h @@ -0,0 +1,66 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * + * 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> + */ + +#ifndef _LINUX_I2C_MUX_H +#define _LINUX_I2C_MUX_H + +#ifdef __KERNEL__ + +#include <linux/bitops.h> + +struct i2c_mux_core { + struct i2c_adapter *parent; + struct device *dev; + unsigned int mux_locked:1; + unsigned int arbitrator:1; + unsigned int gate:1; + + void *priv; + + int (*select)(struct i2c_mux_core *, u32 chan_id); + int (*deselect)(struct i2c_mux_core *, u32 chan_id); + + int num_adapters; + int max_adapters; + struct i2c_adapter *adapter[]; +}; + +struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent, + struct device *dev, int max_adapters, + int sizeof_priv, u32 flags, + int (*select)(struct i2c_mux_core *, u32), + int (*deselect)(struct i2c_mux_core *, u32)); + +/* flags for i2c_mux_alloc */ +#define I2C_MUX_LOCKED BIT(0) +#define I2C_MUX_ARBITRATOR BIT(1) +#define I2C_MUX_GATE BIT(2) + +static inline void *i2c_mux_priv(struct i2c_mux_core *muxc) +{ + return muxc->priv; +} + +struct i2c_adapter *i2c_root_adapter(struct device *dev); + +/* + * Called to create an i2c bus on a multiplexed bus segment. + * The chan_id parameter is passed to the select and deselect + * callback functions to perform hardware-specific mux control. + */ +int i2c_mux_add_adapter(struct i2c_mux_core *muxc, + u32 force_nr, u32 chan_id, + unsigned int class); + +void i2c_mux_del_adapters(struct i2c_mux_core *muxc); + +#endif /* __KERNEL__ */ + +#endif /* _LINUX_I2C_MUX_H */ |