drm/i915/intel_i2c: refactor using intel_gmbus_get_adapter
Instead of letting other modules directly access the ->gmbus array,
introduce intel_gmbus_get_adapter() for looking up an i2c_adapter
for a given gmbus port identifier. This will enable later refactoring
of the gmbus port list.
Note: Before requesting an adapter for a given gmbus port number, the
driver must first check its validity using i2c_intel_gmbus_is_port_valid().
If this check fails, a call to intel_gmbus_get_adapter() will WARN_ON and
return NULL. This is relevant for parts of the driver that read a port
from VBIOS, which might be improperly initialized and contain an invalid
port. In these cases, the driver must fall back to using a safer default
port.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e11fcb0..44e6430 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1342,6 +1342,13 @@
/* intel_i2c.c */
extern int intel_setup_gmbus(struct drm_device *dev);
extern void intel_teardown_gmbus(struct drm_device *dev);
+extern inline bool intel_gmbus_is_port_valid(unsigned port)
+{
+ return (port >= GMBUS_PORT_DISABLED && port <= GMBUS_PORT_RESERVED);
+}
+
+extern struct i2c_adapter *intel_gmbus_get_adapter(
+ struct drm_i915_private *dev_priv, unsigned port);
extern void intel_gmbus_set_speed(struct i2c_adapter *adapter, int speed);
extern void intel_gmbus_force_bit(struct i2c_adapter *adapter, bool force_bit);
extern inline bool intel_gmbus_is_forced_bit(struct i2c_adapter *adapter)