xref: /linux/drivers/gpu/drm/tilcdc/tilcdc_encoder.c (revision 2c6f1b1fa78acd5f3bd80e3519b6b23907ea9c2f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 Texas Instruments
4  * Author: Jyri Sarha <jsarha@ti.com>
5  */
6 
7 #include <linux/of_graph.h>
8 
9 #include <drm/drm_atomic_helper.h>
10 #include <drm/drm_bridge.h>
11 #include <drm/drm_of.h>
12 #include <drm/drm_simple_kms_helper.h>
13 
14 #include "tilcdc_drv.h"
15 #include "tilcdc_encoder.h"
16 
17 static
18 struct drm_connector *tilcdc_encoder_find_connector(struct drm_device *ddev,
19 						    struct drm_encoder *encoder)
20 {
21 	struct drm_connector *connector;
22 
23 	list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
24 		if (drm_connector_has_possible_encoder(connector, encoder))
25 			return connector;
26 	}
27 
28 	drm_err(ddev, "No connector found for %s encoder (id %d)\n",
29 		encoder->name, encoder->base.id);
30 
31 	return NULL;
32 }
33 
34 static
35 int tilcdc_attach_bridge(struct drm_device *ddev, struct drm_bridge *bridge)
36 {
37 	struct tilcdc_drm_private *priv = ddev_to_tilcdc_priv(ddev);
38 	int ret;
39 
40 	priv->encoder->base.possible_crtcs = BIT(0);
41 
42 	ret = drm_bridge_attach(&priv->encoder->base, bridge, NULL, 0);
43 	if (ret)
44 		return ret;
45 
46 	priv->connector = tilcdc_encoder_find_connector(ddev, &priv->encoder->base);
47 	if (!priv->connector)
48 		return -ENODEV;
49 
50 	return 0;
51 }
52 
53 int tilcdc_encoder_create(struct drm_device *ddev)
54 {
55 	struct tilcdc_drm_private *priv = ddev_to_tilcdc_priv(ddev);
56 	struct tilcdc_encoder *encoder;
57 	struct drm_bridge *bridge;
58 	struct drm_panel *panel;
59 	int ret;
60 
61 	ret = drm_of_find_panel_or_bridge(ddev->dev->of_node, 0, 0,
62 					  &panel, &bridge);
63 	if (ret == -ENODEV)
64 		return 0;
65 	else if (ret)
66 		return ret;
67 
68 	encoder = drmm_simple_encoder_alloc(ddev, struct tilcdc_encoder,
69 					    base, DRM_MODE_ENCODER_NONE);
70 	if (IS_ERR(encoder)) {
71 		drm_err(ddev, "drm_encoder_init() failed %pe\n", encoder);
72 		return PTR_ERR(encoder);
73 	}
74 	priv->encoder = encoder;
75 
76 	if (panel) {
77 		bridge = devm_drm_panel_bridge_add_typed(ddev->dev, panel,
78 							 DRM_MODE_CONNECTOR_DPI);
79 		if (IS_ERR(bridge))
80 			return PTR_ERR(bridge);
81 	}
82 
83 	return tilcdc_attach_bridge(ddev, bridge);
84 }
85