diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/i2c-mux.h | 55 | ||||
-rw-r--r-- | include/linux/i2c.h | 50 | ||||
-rw-r--r-- | include/uapi/linux/i2c.h | 13 |
3 files changed, 96 insertions, 22 deletions
diff --git a/include/linux/i2c-mux.h b/include/linux/i2c-mux.h index b5f9a007a3ab..d4c1d12f900d 100644 --- a/include/linux/i2c-mux.h +++ b/include/linux/i2c-mux.h @@ -27,22 +27,49 @@ #ifdef __KERNEL__ +#include <linux/bitops.h> + +struct i2c_mux_core { + struct i2c_adapter *parent; + struct device *dev; + bool mux_locked; + + 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[0]; +}; + +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) + +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 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. + * 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. */ -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)); - -void i2c_del_mux_adapter(struct i2c_adapter *adap); +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__ */ diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 200cf13b00f6..96a25ae14494 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -524,6 +524,7 @@ struct i2c_adapter { /* data fields that are valid for all devices */ struct rt_mutex bus_lock; + struct rt_mutex mux_lock; int timeout; /* in jiffies */ int retries; @@ -538,6 +539,10 @@ struct i2c_adapter { struct i2c_bus_recovery_info *bus_recovery_info; const struct i2c_adapter_quirks *quirks; + + void (*lock_bus)(struct i2c_adapter *, unsigned int flags); + int (*trylock_bus)(struct i2c_adapter *, unsigned int flags); + void (*unlock_bus)(struct i2c_adapter *, unsigned int flags); }; #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) @@ -567,8 +572,44 @@ i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter) int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)); /* Adapter locking functions, exported for shared pin cases */ -void i2c_lock_adapter(struct i2c_adapter *); -void i2c_unlock_adapter(struct i2c_adapter *); +#define I2C_LOCK_ROOT_ADAPTER BIT(0) +#define I2C_LOCK_SEGMENT BIT(1) + +/** + * i2c_lock_bus - Get exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT + * locks only this branch in the adapter tree + */ +static inline void +i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + adapter->lock_bus(adapter, flags); +} + +/** + * i2c_unlock_bus - Release exclusive access to an I2C bus segment + * @adapter: Target I2C bus segment + * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT + * unlocks only this branch in the adapter tree + */ +static inline void +i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) +{ + adapter->unlock_bus(adapter, flags); +} + +static inline void +i2c_lock_adapter(struct i2c_adapter *adapter) +{ + i2c_lock_bus(adapter, I2C_LOCK_ROOT_ADAPTER); +} + +static inline void +i2c_unlock_adapter(struct i2c_adapter *adapter) +{ + i2c_unlock_bus(adapter, I2C_LOCK_ROOT_ADAPTER); +} /*flags for the client struct: */ #define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */ @@ -654,6 +695,11 @@ static inline int i2c_adapter_id(struct i2c_adapter *adap) return adap->nr; } +static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg) +{ + return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0); +} + /** * module_i2c_driver() - Helper macro for registering a modular I2C driver * @__i2c_driver: i2c_driver struct diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h index b0a7dd61eb35..adcbef4bff61 100644 --- a/include/uapi/linux/i2c.h +++ b/include/uapi/linux/i2c.h @@ -68,14 +68,15 @@ struct i2c_msg { __u16 addr; /* slave address */ __u16 flags; -#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */ #define I2C_M_RD 0x0001 /* read data, from slave to master */ -#define I2C_M_STOP 0x8000 /* if I2C_FUNC_PROTOCOL_MANGLING */ -#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_NOSTART */ -#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */ -#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ -#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ + /* I2C_M_RD is guaranteed to be 0x0001! */ +#define I2C_M_TEN 0x0010 /* this is a ten bit chip address */ #define I2C_M_RECV_LEN 0x0400 /* length will be first received byte */ +#define I2C_M_NO_RD_ACK 0x0800 /* if I2C_FUNC_PROTOCOL_MANGLING */ +#define I2C_M_IGNORE_NAK 0x1000 /* if I2C_FUNC_PROTOCOL_MANGLING */ +#define I2C_M_REV_DIR_ADDR 0x2000 /* if I2C_FUNC_PROTOCOL_MANGLING */ +#define I2C_M_NOSTART 0x4000 /* if I2C_FUNC_NOSTART */ +#define I2C_M_STOP 0x8000 /* if I2C_FUNC_PROTOCOL_MANGLING */ __u16 len; /* msg length */ __u8 *buf; /* pointer to msg data */ }; |