summaryrefslogtreecommitdiff
path: root/include/linux/i2c.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/i2c.h')
-rw-r--r--include/linux/i2c.h47
1 files changed, 41 insertions, 6 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index fffdc270ca18..6422eef428c4 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -427,6 +427,20 @@ struct i2c_algorithm {
};
/**
+ * struct i2c_lock_operations - represent I2C locking operations
+ * @lock_bus: Get exclusive access to an I2C bus segment
+ * @trylock_bus: Try to get exclusive access to an I2C bus segment
+ * @unlock_bus: Release exclusive access to an I2C bus segment
+ *
+ * The main operations are wrapped by i2c_lock_bus and i2c_unlock_bus.
+ */
+struct i2c_lock_operations {
+ 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);
+};
+
+/**
* struct i2c_timings - I2C timing information
* @bus_freq_hz: the bus frequency in Hz
* @scl_rise_ns: time SCL signal takes to rise in ns; t(r) in the I2C specification
@@ -536,6 +550,7 @@ struct i2c_adapter {
void *algo_data;
/* data fields that are valid for all devices */
+ const struct i2c_lock_operations *lock_ops;
struct rt_mutex bus_lock;
struct rt_mutex mux_lock;
@@ -552,10 +567,6 @@ 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)
@@ -597,7 +608,21 @@ int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *));
static inline void
i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags)
{
- adapter->lock_bus(adapter, flags);
+ adapter->lock_ops->lock_bus(adapter, flags);
+}
+
+/**
+ * i2c_trylock_bus - Try to get exclusive access to an I2C bus segment
+ * @adapter: Target I2C bus segment
+ * @flags: I2C_LOCK_ROOT_ADAPTER tries to locks the root i2c adapter,
+ * I2C_LOCK_SEGMENT tries to lock only this branch in the adapter tree
+ *
+ * Return: true if the I2C bus segment is locked, false otherwise
+ */
+static inline int
+i2c_trylock_bus(struct i2c_adapter *adapter, unsigned int flags)
+{
+ return adapter->lock_ops->trylock_bus(adapter, flags);
}
/**
@@ -609,7 +634,7 @@ i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags)
static inline void
i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags)
{
- adapter->unlock_bus(adapter, flags);
+ adapter->lock_ops->unlock_bus(adapter, flags);
}
static inline void
@@ -673,6 +698,7 @@ extern void i2c_clients_command(struct i2c_adapter *adap,
extern struct i2c_adapter *i2c_get_adapter(int nr);
extern void i2c_put_adapter(struct i2c_adapter *adap);
+extern unsigned int i2c_adapter_depth(struct i2c_adapter *adapter);
void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults);
@@ -766,4 +792,13 @@ static inline struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node
}
#endif /* CONFIG_OF */
+#if IS_ENABLED(CONFIG_ACPI)
+u32 i2c_acpi_find_bus_speed(struct device *dev);
+#else
+static inline u32 i2c_acpi_find_bus_speed(struct device *dev)
+{
+ return 0;
+}
+#endif /* CONFIG_ACPI */
+
#endif /* _LINUX_I2C_H */