1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * rcar_du_encoder.c -- R-Car Display Unit Encoder
4 *
5 * Copyright (C) 2013-2014 Renesas Electronics Corporation
6 *
7 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
8 */
9
10 #include <linux/export.h>
11
12 #include <drm/drm_crtc.h>
13 #include <drm/drm_modeset_helper_vtables.h>
14 #include <drm/drm_panel.h>
15
16 #include "rcar_du_drv.h"
17 #include "rcar_du_encoder.h"
18 #include "rcar_du_kms.h"
19 #include "rcar_lvds.h"
20
21 /* -----------------------------------------------------------------------------
22 * Encoder
23 */
24
25 static const struct drm_encoder_helper_funcs encoder_helper_funcs = {
26 };
27
28 static const struct drm_encoder_funcs encoder_funcs = {
29 .destroy = drm_encoder_cleanup,
30 };
31
rcar_du_encoder_count_ports(struct device_node * node)32 static unsigned int rcar_du_encoder_count_ports(struct device_node *node)
33 {
34 struct device_node *ports;
35 struct device_node *port;
36 unsigned int num_ports = 0;
37
38 ports = of_get_child_by_name(node, "ports");
39 if (!ports)
40 ports = of_node_get(node);
41
42 for_each_child_of_node(ports, port) {
43 if (of_node_name_eq(port, "port"))
44 num_ports++;
45 }
46
47 of_node_put(ports);
48
49 return num_ports;
50 }
51
rcar_du_encoder_init(struct rcar_du_device * rcdu,enum rcar_du_output output,struct device_node * enc_node)52 int rcar_du_encoder_init(struct rcar_du_device *rcdu,
53 enum rcar_du_output output,
54 struct device_node *enc_node)
55 {
56 struct rcar_du_encoder *renc;
57 struct drm_encoder *encoder;
58 struct drm_bridge *bridge;
59 int ret;
60
61 renc = devm_kzalloc(rcdu->dev, sizeof(*renc), GFP_KERNEL);
62 if (renc == NULL)
63 return -ENOMEM;
64
65 rcdu->encoders[output] = renc;
66 renc->output = output;
67 encoder = rcar_encoder_to_drm_encoder(renc);
68
69 dev_dbg(rcdu->dev, "initializing encoder %pOF for output %u\n",
70 enc_node, output);
71
72 /*
73 * Locate the DRM bridge from the DT node. For the DPAD outputs, if the
74 * DT node has a single port, assume that it describes a panel and
75 * create a panel bridge.
76 */
77 if ((output == RCAR_DU_OUTPUT_DPAD0 ||
78 output == RCAR_DU_OUTPUT_DPAD1) &&
79 rcar_du_encoder_count_ports(enc_node) == 1) {
80 struct drm_panel *panel = of_drm_find_panel(enc_node);
81
82 if (IS_ERR(panel)) {
83 ret = PTR_ERR(panel);
84 goto done;
85 }
86
87 bridge = devm_drm_panel_bridge_add(rcdu->dev, panel,
88 DRM_MODE_CONNECTOR_DPI);
89 if (IS_ERR(bridge)) {
90 ret = PTR_ERR(bridge);
91 goto done;
92 }
93 } else {
94 bridge = of_drm_find_bridge(enc_node);
95 if (!bridge) {
96 ret = -EPROBE_DEFER;
97 goto done;
98 }
99 }
100
101 /*
102 * On Gen3 skip the LVDS1 output if the LVDS1 encoder is used as a
103 * companion for LVDS0 in dual-link mode.
104 */
105 if (rcdu->info->gen >= 3 && output == RCAR_DU_OUTPUT_LVDS1) {
106 if (rcar_lvds_dual_link(bridge)) {
107 ret = -ENOLINK;
108 goto done;
109 }
110 }
111
112 ret = drm_encoder_init(rcdu->ddev, encoder, &encoder_funcs,
113 DRM_MODE_ENCODER_NONE, NULL);
114 if (ret < 0)
115 goto done;
116
117 drm_encoder_helper_add(encoder, &encoder_helper_funcs);
118
119 /*
120 * Attach the bridge to the encoder. The bridge will create the
121 * connector.
122 */
123 ret = drm_bridge_attach(encoder, bridge, NULL);
124 if (ret) {
125 drm_encoder_cleanup(encoder);
126 return ret;
127 }
128
129 done:
130 if (ret < 0) {
131 if (encoder->name)
132 encoder->funcs->destroy(encoder);
133 devm_kfree(rcdu->dev, renc);
134 }
135
136 return ret;
137 }
138
