Commit 63170ac6 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/simple-kms: Add drm_simple_encoder_{init,create}() 



This patch makes the internal encoder implementation of the simple
KMS helpers available to drivers.

These simple-encoder helpers initialize an encoder with an empty
implementation. This covers the requirements of most of the existing
DRM drivers. A call to drm_simple_encoder_create() allocates and
initializes an encoder instance, a call to drm_simple_encoder_init()
initializes a pre-allocated instance.

v3:
	* remove drm_simple_encoder_create(); not required yet
	* provide more precise documentation
v2:
	* move simple encoder to KMS helpers
	* remove name argument; simplifies implementation
	* don't allocate with devm_ interfaces; unsafe with DRM

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200228081828.18463-2-tzimmermann@suse.de
parent 4a1d0dbc

drivers/gpu/drm/drm_simple_kms_helper.c

+31 −3
Original line number Diff line number Diff line
@@ -26,12 +26,41 @@ 
 * entity. Some flexibility for code reuse is provided through a separately

 * allocated &drm_connector object and supporting optional &drm_bridge

 * encoder drivers.

 *

 * Many drivers require only a very simple encoder that fulfills the minimum

 * requirements of the display pipeline and does not add additional

 * functionality. The function drm_simple_encoder_init() provides an

 * implementation of such an encoder.

 */



static const struct drm_encoder_funcs drm_simple_kms_encoder_funcs = {

static const struct drm_encoder_funcs drm_simple_encoder_funcs_cleanup = {

	.destroy = drm_encoder_cleanup,

};



/**

 * drm_simple_encoder_init - Initialize a preallocated encoder

 * @dev: drm device

 * @funcs: callbacks for this encoder

 * @encoder_type: user visible type of the encoder

 *

 * Initialises a preallocated encoder that has no further functionality.

 * Settings for possible CRTC and clones are left to their initial values.

 * The encoder will be cleaned up automatically as part of the mode-setting

 * cleanup.

 *

 * Returns:

 * Zero on success, error code on failure.

 */

int drm_simple_encoder_init(struct drm_device *dev,

			    struct drm_encoder *encoder,

			    int encoder_type)

{

	return drm_encoder_init(dev, encoder,

				&drm_simple_encoder_funcs_cleanup,

				encoder_type, NULL);

}

EXPORT_SYMBOL(drm_simple_encoder_init);



static enum drm_mode_status

drm_simple_kms_crtc_mode_valid(struct drm_crtc *crtc,

			       const struct drm_display_mode *mode)
@@ -288,8 +317,7 @@ int drm_simple_display_pipe_init(struct drm_device *dev, 
		return ret;



	encoder->possible_crtcs = drm_crtc_mask(crtc);

	ret = drm_encoder_init(dev, encoder, &drm_simple_kms_encoder_funcs,

			       DRM_MODE_ENCODER_NONE, NULL);

	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_NONE);

	if (ret || !connector)

		return ret;

include/drm/drm_simple_kms_helper.h

+4 −0
Original line number Diff line number Diff line
@@ -181,4 +181,8 @@ int drm_simple_display_pipe_init(struct drm_device *dev, 
			const uint64_t *format_modifiers,

			struct drm_connector *connector);



int drm_simple_encoder_init(struct drm_device *dev,

			    struct drm_encoder *encoder,

			    int encoder_type);



#endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */

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