Commit bac9c294 authored by Douglas Anderson's avatar Douglas Anderson
Browse files

drm/edid: Break out reading block 0 of the EDID 



A future change wants to be able to read just block 0 of the EDID, so
break it out of drm_do_get_edid() into a sub-function.

This is intended to be a no-op change--just code movement.

Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
Acked-by: default avatarSam Ravnborg <sam@ravnborg.org>
Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210914132020.v5.2.I62e76a034ac78c994d40a23cd4ec5aeee56fa77c@changeid
parent 29145a56

drivers/gpu/drm/drm_edid.c

+45 −18
Original line number Diff line number Diff line
@@ -1905,6 +1905,44 @@ int drm_add_override_edid_modes(struct drm_connector *connector) 
}

EXPORT_SYMBOL(drm_add_override_edid_modes);



static struct edid *drm_do_get_edid_base_block(

	int (*get_edid_block)(void *data, u8 *buf, unsigned int block,

			      size_t len),

	void *data, bool *edid_corrupt, int *null_edid_counter)

{

	int i;

	void *edid;



	edid = kmalloc(EDID_LENGTH, GFP_KERNEL);

	if (edid == NULL)

		return NULL;



	/* base block fetch */

	for (i = 0; i < 4; i++) {

		if (get_edid_block(data, edid, 0, EDID_LENGTH))

			goto out;

		if (drm_edid_block_valid(edid, 0, false, edid_corrupt))

			break;

		if (i == 0 && drm_edid_is_zero(edid, EDID_LENGTH)) {

			if (null_edid_counter)

				(*null_edid_counter)++;

			goto carp;

		}

	}

	if (i == 4)

		goto carp;



	return edid;



carp:

	kfree(edid);

	return ERR_PTR(-EINVAL);



out:

	kfree(edid);

	return NULL;

}



/**

 * drm_do_get_edid - get EDID data using a custom EDID block read function

 * @connector: connector we're probing
@@ -1938,25 +1976,16 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, 
	if (override)

		return override;



	if ((edid = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL)

	edid = (u8 *)drm_do_get_edid_base_block(get_edid_block, data,

						&connector->edid_corrupt,

						&connector->null_edid_counter);

	if (IS_ERR_OR_NULL(edid)) {

		if (IS_ERR(edid))

			connector_bad_edid(connector, edid, 1);

		return NULL;



	/* base block fetch */

	for (i = 0; i < 4; i++) {

		if (get_edid_block(data, edid, 0, EDID_LENGTH))

			goto out;

		if (drm_edid_block_valid(edid, 0, false,

					 &connector->edid_corrupt))

			break;

		if (i == 0 && drm_edid_is_zero(edid, EDID_LENGTH)) {

			connector->null_edid_counter++;

			goto carp;

	}

	}

	if (i == 4)

		goto carp;



	/* if there's no extensions, we're done */

	/* if there's no extensions or no connector, we're done */

	valid_extensions = edid[0x7e];

	if (valid_extensions == 0)

		return (struct edid *)edid;
@@ -2010,8 +2039,6 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, 


	return (struct edid *)edid;



carp:

	connector_bad_edid(connector, edid, 1);

out:

	kfree(edid);

	return NULL;