xref: /netbsd-src/sys/dev/fdt/hdmi_connector.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /* $NetBSD: hdmi_connector.c,v 1.1 2019/01/30 01:24:00 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2019 Jared McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: hdmi_connector.c,v 1.1 2019/01/30 01:24:00 jmcneill Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/systm.h>
36 #include <sys/gpio.h>
37 
38 #include <dev/fdt/fdtvar.h>
39 #include <dev/fdt/fdt_port.h>
40 
41 #include <dev/i2c/ddcvar.h>
42 
43 #include <drm/drmP.h>
44 #include <drm/drm_crtc.h>
45 #include <drm/drm_crtc_helper.h>
46 #include <drm/drm_edid.h>
47 
48 static const char * const compatible[] = {
49 	"hdmi-connector",
50 	NULL
51 };
52 
53 struct dispcon_hdmi_connector {
54 	struct drm_connector		base;
55 	struct fdtbus_gpio_pin		*hpd;
56 	i2c_tag_t			ddc;
57 
58 	int				type;	/* DRM_MODE_CONNECTOR_* */
59 };
60 
61 struct dispcon_hdmi_softc {
62 	struct fdt_device_ports		sc_ports;
63 	struct dispcon_hdmi_connector	sc_connector;
64 };
65 
66 #define	to_dispcon_hdmi_connector(x)	container_of(x, struct dispcon_hdmi_connector, base)
67 
68 static enum drm_connector_status
69 dispcon_hdmi_connector_detect(struct drm_connector *connector, bool force)
70 {
71 	struct dispcon_hdmi_connector *hdmi_connector = to_dispcon_hdmi_connector(connector);
72 	bool con;
73 
74 	if (hdmi_connector->hpd == NULL) {
75 		/*
76 		 * No hotplug detect pin available. Assume that we are connected.
77 		 */
78 		return connector_status_connected;
79 	}
80 
81 	/*
82 	 * Read connect status from hotplug detect pin.
83 	 */
84 	con = fdtbus_gpio_read(hdmi_connector->hpd);
85 	if (con) {
86 		return connector_status_connected;
87 	} else {
88 		return connector_status_disconnected;
89 	}
90 }
91 
92 static void
93 dispcon_hdmi_connector_destroy(struct drm_connector *connector)
94 {
95 	drm_connector_unregister(connector);
96 	drm_connector_cleanup(connector);
97 }
98 
99 static const struct drm_connector_funcs dispcon_hdmi_connector_funcs = {
100 	.dpms = drm_helper_connector_dpms,
101 	.detect = dispcon_hdmi_connector_detect,
102 	.fill_modes = drm_helper_probe_single_connector_modes,
103 	.destroy = dispcon_hdmi_connector_destroy,
104 };
105 
106 static int
107 dispcon_hdmi_connector_mode_valid(struct drm_connector *connector, struct drm_display_mode *mode)
108 {
109 	return MODE_OK;
110 }
111 
112 static int
113 dispcon_hdmi_connector_get_modes(struct drm_connector *connector)
114 {
115 	struct dispcon_hdmi_connector *hdmi_connector = to_dispcon_hdmi_connector(connector);
116 	char edid[EDID_LENGTH * 4];
117 	struct edid *pedid = NULL;
118 	int error, block;
119 
120 	if (hdmi_connector->ddc != NULL) {
121 		memset(edid, 0, sizeof(edid));
122 		for (block = 0; block < 4; block++) {
123 			error = ddc_read_edid_block(hdmi_connector->ddc,
124 			    &edid[block * EDID_LENGTH], EDID_LENGTH, block);
125 			if (error)
126 				break;
127 			if (block == 0) {
128 				pedid = (struct edid *)edid;
129 				if (edid[0x7e] == 0)
130 					break;
131 			}
132 		}
133 	}
134 
135 	drm_mode_connector_update_edid_property(connector, pedid);
136 	if (pedid == NULL)
137 		return 0;
138 
139 	error = drm_add_edid_modes(connector, pedid);
140 	drm_edid_to_eld(connector, pedid);
141 
142 	return error;
143 }
144 
145 static struct drm_encoder *
146 dispcon_hdmi_connector_best_encoder(struct drm_connector *connector)
147 {
148 	int enc_id = connector->encoder_ids[0];
149 	struct drm_mode_object *obj;
150 	struct drm_encoder *encoder = NULL;
151 
152 	if (enc_id) {
153 		obj = drm_mode_object_find(connector->dev, enc_id,
154 		    DRM_MODE_OBJECT_ENCODER);
155 		if (obj == NULL)
156 			return NULL;
157 		encoder = obj_to_encoder(obj);
158 	}
159 
160 	return encoder;
161 }
162 
163 static const struct drm_connector_helper_funcs dispcon_hdmi_connector_helper_funcs = {
164 	.mode_valid = dispcon_hdmi_connector_mode_valid,
165 	.get_modes = dispcon_hdmi_connector_get_modes,
166 	.best_encoder = dispcon_hdmi_connector_best_encoder,
167 };
168 
169 static int
170 dispcon_hdmi_ep_activate(device_t dev, struct fdt_endpoint *ep, bool activate)
171 {
172 	struct drm_connector *connector = fdt_endpoint_get_data(ep);
173 	struct dispcon_hdmi_connector *hdmi_connector = to_dispcon_hdmi_connector(connector);
174 	struct fdt_endpoint *rep = fdt_endpoint_remote(ep);
175 	struct drm_encoder *encoder;
176 
177 	if (fdt_endpoint_port_index(ep) != 0)
178 		return EINVAL;
179 
180 	if (fdt_endpoint_type(rep) != EP_DRM_ENCODER)
181 		return EINVAL;
182 
183 	if (activate) {
184 		encoder = fdt_endpoint_get_data(rep);
185 
186 		connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
187 		connector->interlace_allowed = 0;
188 		connector->doublescan_allowed = 0;
189 
190 		drm_connector_init(encoder->dev, connector, &dispcon_hdmi_connector_funcs,
191 		    hdmi_connector->type);
192 		drm_connector_helper_add(connector, &dispcon_hdmi_connector_helper_funcs);
193 		drm_connector_register(connector);
194 		drm_mode_connector_attach_encoder(connector, encoder);
195 	}
196 
197 	return 0;
198 }
199 
200 static void *
201 dispcon_hdmi_ep_get_data(device_t dev, struct fdt_endpoint *ep)
202 {
203 	struct dispcon_hdmi_softc * const sc = device_private(dev);
204 
205 	return &sc->sc_connector.base;
206 }
207 
208 static int
209 dispcon_hdmi_match(device_t parent, cfdata_t cf, void *aux)
210 {
211 	struct fdt_attach_args * const faa = aux;
212 
213 	return of_match_compatible(faa->faa_phandle, compatible);
214 }
215 
216 static void
217 dispcon_hdmi_attach(device_t parent, device_t self, void *aux)
218 {
219 	struct dispcon_hdmi_softc * const sc = device_private(self);
220 	struct dispcon_hdmi_connector * const hdmi_connector = &sc->sc_connector;
221 	struct fdt_attach_args * const faa = aux;
222 	const int phandle = faa->faa_phandle;
223 
224 	aprint_naive("\n");
225 	aprint_normal(": HDMI connector\n");
226 
227 	hdmi_connector->type = DRM_MODE_CONNECTOR_HDMIA;
228 	hdmi_connector->hpd = fdtbus_gpio_acquire(phandle, "hpd-gpios", GPIO_PIN_INPUT);
229 	hdmi_connector->ddc = fdtbus_i2c_acquire(phandle, "ddc-i2c-bus");
230 
231 	sc->sc_ports.dp_ep_activate = dispcon_hdmi_ep_activate;
232 	sc->sc_ports.dp_ep_get_data = dispcon_hdmi_ep_get_data;
233 	fdt_ports_register(&sc->sc_ports, self, phandle, EP_DRM_CONNECTOR);
234 }
235 
236 CFATTACH_DECL_NEW(dispcon_hdmi, sizeof(struct dispcon_hdmi_softc),
237 	dispcon_hdmi_match, dispcon_hdmi_attach, NULL, NULL);
238