diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 6e6514ef996899c5df404a53573794c6ed304b92..4132d58dab93ed7fd10ac43ba4951042cd78b33d 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1160,6 +1160,29 @@ int drm_encoder_init(struct drm_device *dev, } EXPORT_SYMBOL(drm_encoder_init); +/** + * drm_encoder_index - find the index of a registered encoder + * @encoder: encoder to find index for + * + * Given a registered encoder, return the index of that encoder within a DRM + * device's list of encoders. + */ +unsigned int drm_encoder_index(struct drm_encoder *encoder) +{ + unsigned int index = 0; + struct drm_encoder *tmp; + + drm_for_each_encoder(tmp, encoder->dev) { + if (tmp == encoder) + return index; + + index++; + } + + BUG(); +} +EXPORT_SYMBOL(drm_encoder_index); + /** * drm_encoder_cleanup - cleans up an initialised encoder * @encoder: encoder to cleanup diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index c65a212db77e7a99b26735c262cb31a9b2504195..fd2ace4a18de869a8126fff44cb4eb617c903ee2 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -2225,6 +2225,7 @@ int drm_encoder_init(struct drm_device *dev, struct drm_encoder *encoder, const struct drm_encoder_funcs *funcs, int encoder_type, const char *name, ...); +extern unsigned int drm_encoder_index(struct drm_encoder *encoder); /** * drm_encoder_crtc_ok - can a given crtc drive a given encoder?