| 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| 2 | /* |
| 3 | * |
| 4 | * i2c-mux.h - functions for the i2c-bus mux support |
| 5 | * |
| 6 | * Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it> |
| 7 | * Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it> |
| 8 | * Michael Lawnick <michael.lawnick.ext@nsn.com> |
| 9 | */ |
| 10 | |
| 11 | #ifndef _LINUX_I2C_MUX_H |
| 12 | #define _LINUX_I2C_MUX_H |
| 13 | |
| 14 | #ifdef __KERNEL__ |
| 15 | |
| 16 | #include <linux/bitops.h> |
| 17 | |
| 18 | struct i2c_mux_core { |
| 19 | struct i2c_adapter *parent; |
| 20 | struct device *dev; |
| 21 | unsigned int mux_locked:1; |
| 22 | unsigned int arbitrator:1; |
| 23 | unsigned int gate:1; |
| 24 | |
| 25 | void *priv; |
| 26 | |
| 27 | int (*select)(struct i2c_mux_core *, u32 chan_id); |
| 28 | int (*deselect)(struct i2c_mux_core *, u32 chan_id); |
| 29 | |
| 30 | int num_adapters; |
| 31 | int max_adapters; |
| 32 | struct i2c_adapter *adapter[]; |
| 33 | }; |
| 34 | |
| 35 | struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent, |
| 36 | struct device *dev, int max_adapters, |
| 37 | int sizeof_priv, u32 flags, |
| 38 | int (*select)(struct i2c_mux_core *, u32), |
| 39 | int (*deselect)(struct i2c_mux_core *, u32)); |
| 40 | |
| 41 | /* flags for i2c_mux_alloc */ |
| 42 | #define I2C_MUX_LOCKED BIT(0) |
| 43 | #define I2C_MUX_ARBITRATOR BIT(1) |
| 44 | #define I2C_MUX_GATE BIT(2) |
| 45 | |
| 46 | static inline void *i2c_mux_priv(struct i2c_mux_core *muxc) |
| 47 | { |
| 48 | return muxc->priv; |
| 49 | } |
| 50 | |
| 51 | struct i2c_adapter *i2c_root_adapter(struct device *dev); |
| 52 | |
| 53 | /* |
| 54 | * Called to create an i2c bus on a multiplexed bus segment. |
| 55 | * The chan_id parameter is passed to the select and deselect |
| 56 | * callback functions to perform hardware-specific mux control. |
| 57 | */ |
| 58 | int i2c_mux_add_adapter(struct i2c_mux_core *muxc, |
| 59 | u32 force_nr, u32 chan_id); |
| 60 | |
| 61 | void i2c_mux_del_adapters(struct i2c_mux_core *muxc); |
| 62 | |
| 63 | #endif /* __KERNEL__ */ |
| 64 | |
| 65 | #endif /* _LINUX_I2C_MUX_H */ |