i2c: export bit-banging algo functions
i915 has a hw i2c controller (gmbus) but for a bunch of stupid reasons
we need to be able to fall back to the bit-banging algo on gpio pins.
The current code sets up a 2nd i2c controller for the same i2c bus using
the bit-banging algo. This has a bunch of issues, the major one being
that userspace can directly access this fallback i2c adaptor behind
the drivers back.
But we need to frob a few registers before and after using fallback
gpio bit-banging, so this horribly fails.
The new plan is to only set up one i2c adaptor and transparently fall
back to bit-banging by directly calling the xfer function of the bit-
banging algo in the i2c core.
To make that possible, export the 2 i2c algo functions.
v2: As suggested by Jean Delvare, simply export the i2c_bit_algo
vtable instead of the individual functions.
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/include/linux/i2c-algo-bit.h b/include/linux/i2c-algo-bit.h
index 4f98148..584ffa0 100644
--- a/include/linux/i2c-algo-bit.h
+++ b/include/linux/i2c-algo-bit.h
@@ -49,5 +49,6 @@
int i2c_bit_add_bus(struct i2c_adapter *);
int i2c_bit_add_numbered_bus(struct i2c_adapter *);
+extern const struct i2c_algorithm i2c_bit_algo;
#endif /* _LINUX_I2C_ALGO_BIT_H */