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/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index e4317da..871aa27 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -372,11 +372,11 @@
if (block_size >= sizeof(*general)) {
int bus_pin = general->crt_ddc_gmbus_pin;
DRM_DEBUG_KMS("crt_ddc_bus_pin: %d\n", bus_pin);
- if (bus_pin >= 1 && bus_pin <= 6)
+ if (intel_gmbus_is_port_valid(bus_pin))
dev_priv->crt_ddc_pin = bus_pin;
} else {
DRM_DEBUG_KMS("BDB_GD too small (%d). Invalid.\n",
- block_size);
+ block_size);
}
}
}