1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * i.MX drm driver - parallel display implementation
4  *
5  * Copyright (C) 2012 Sascha Hauer, Pengutronix
6  */
7 
8 #include <linux/component.h>
9 #include <linux/media-bus-format.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/videodev2.h>
14 
15 #include <video/of_display_timing.h>
16 
17 #include <drm/drm_atomic_helper.h>
18 #include <drm/drm_bridge.h>
19 #include <drm/drm_edid.h>
20 #include <drm/drm_managed.h>
21 #include <drm/drm_of.h>
22 #include <drm/drm_panel.h>
23 #include <drm/drm_probe_helper.h>
24 #include <drm/drm_simple_kms_helper.h>
25 
26 #include "imx-drm.h"
27 
28 struct imx_parallel_display_encoder {
29 	struct drm_connector connector;
30 	struct drm_encoder encoder;
31 	struct drm_bridge bridge;
32 	struct imx_parallel_display *pd;
33 };
34 
35 struct imx_parallel_display {
36 	struct device *dev;
37 	void *edid;
38 	u32 bus_format;
39 	u32 bus_flags;
40 	struct drm_display_mode mode;
41 	struct drm_panel *panel;
42 	struct drm_bridge *next_bridge;
43 };
44 
45 static inline struct imx_parallel_display *con_to_imxpd(struct drm_connector *c)
46 {
47 	return container_of(c, struct imx_parallel_display_encoder, connector)->pd;
48 }
49 
50 static inline struct imx_parallel_display *bridge_to_imxpd(struct drm_bridge *b)
51 {
52 	return container_of(b, struct imx_parallel_display_encoder, bridge)->pd;
53 }
54 
55 static int imx_pd_connector_get_modes(struct drm_connector *connector)
56 {
57 	struct imx_parallel_display *imxpd = con_to_imxpd(connector);
58 	struct device_node *np = imxpd->dev->of_node;
59 	int num_modes;
60 
61 	num_modes = drm_panel_get_modes(imxpd->panel, connector);
62 	if (num_modes > 0)
63 		return num_modes;
64 
65 	if (imxpd->edid) {
66 		drm_connector_update_edid_property(connector, imxpd->edid);
67 		num_modes = drm_add_edid_modes(connector, imxpd->edid);
68 	}
69 
70 	if (np) {
71 		struct drm_display_mode *mode = drm_mode_create(connector->dev);
72 		int ret;
73 
74 		if (!mode)
75 			return -EINVAL;
76 
77 		ret = of_get_drm_display_mode(np, &imxpd->mode,
78 					      &imxpd->bus_flags,
79 					      OF_USE_NATIVE_MODE);
80 		if (ret) {
81 			drm_mode_destroy(connector->dev, mode);
82 			return ret;
83 		}
84 
85 		drm_mode_copy(mode, &imxpd->mode);
86 		mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
87 		drm_mode_probed_add(connector, mode);
88 		num_modes++;
89 	}
90 
91 	return num_modes;
92 }
93 
94 static void imx_pd_bridge_enable(struct drm_bridge *bridge)
95 {
96 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
97 
98 	drm_panel_prepare(imxpd->panel);
99 	drm_panel_enable(imxpd->panel);
100 }
101 
102 static void imx_pd_bridge_disable(struct drm_bridge *bridge)
103 {
104 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
105 
106 	drm_panel_disable(imxpd->panel);
107 	drm_panel_unprepare(imxpd->panel);
108 }
109 
110 static const u32 imx_pd_bus_fmts[] = {
111 	MEDIA_BUS_FMT_RGB888_1X24,
112 	MEDIA_BUS_FMT_BGR888_1X24,
113 	MEDIA_BUS_FMT_GBR888_1X24,
114 	MEDIA_BUS_FMT_RGB666_1X18,
115 	MEDIA_BUS_FMT_RGB666_1X24_CPADHI,
116 	MEDIA_BUS_FMT_RGB565_1X16,
117 };
118 
119 static u32 *
120 imx_pd_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
121 					 struct drm_bridge_state *bridge_state,
122 					 struct drm_crtc_state *crtc_state,
123 					 struct drm_connector_state *conn_state,
124 					 unsigned int *num_output_fmts)
125 {
126 	struct drm_display_info *di = &conn_state->connector->display_info;
127 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
128 	u32 *output_fmts;
129 
130 	if (!imxpd->bus_format && !di->num_bus_formats) {
131 		*num_output_fmts = ARRAY_SIZE(imx_pd_bus_fmts);
132 		return kmemdup(imx_pd_bus_fmts, sizeof(imx_pd_bus_fmts),
133 			       GFP_KERNEL);
134 	}
135 
136 	*num_output_fmts = 1;
137 	output_fmts = kmalloc(sizeof(*output_fmts), GFP_KERNEL);
138 	if (!output_fmts)
139 		return NULL;
140 
141 	if (!imxpd->bus_format && di->num_bus_formats)
142 		output_fmts[0] = di->bus_formats[0];
143 	else
144 		output_fmts[0] = imxpd->bus_format;
145 
146 	return output_fmts;
147 }
148 
149 static bool imx_pd_format_supported(u32 output_fmt)
150 {
151 	unsigned int i;
152 
153 	for (i = 0; i < ARRAY_SIZE(imx_pd_bus_fmts); i++) {
154 		if (imx_pd_bus_fmts[i] == output_fmt)
155 			return true;
156 	}
157 
158 	return false;
159 }
160 
161 static u32 *
162 imx_pd_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
163 					struct drm_bridge_state *bridge_state,
164 					struct drm_crtc_state *crtc_state,
165 					struct drm_connector_state *conn_state,
166 					u32 output_fmt,
167 					unsigned int *num_input_fmts)
168 {
169 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
170 	u32 *input_fmts;
171 
172 	/*
173 	 * If the next bridge does not support bus format negotiation, let's
174 	 * use the static bus format definition (imxpd->bus_format) if it's
175 	 * specified, RGB888 when it's not.
176 	 */
177 	if (output_fmt == MEDIA_BUS_FMT_FIXED)
178 		output_fmt = imxpd->bus_format ? : MEDIA_BUS_FMT_RGB888_1X24;
179 
180 	/* Now make sure the requested output format is supported. */
181 	if ((imxpd->bus_format && imxpd->bus_format != output_fmt) ||
182 	    !imx_pd_format_supported(output_fmt)) {
183 		*num_input_fmts = 0;
184 		return NULL;
185 	}
186 
187 	*num_input_fmts = 1;
188 	input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
189 	if (!input_fmts)
190 		return NULL;
191 
192 	input_fmts[0] = output_fmt;
193 	return input_fmts;
194 }
195 
196 static int imx_pd_bridge_atomic_check(struct drm_bridge *bridge,
197 				      struct drm_bridge_state *bridge_state,
198 				      struct drm_crtc_state *crtc_state,
199 				      struct drm_connector_state *conn_state)
200 {
201 	struct imx_crtc_state *imx_crtc_state = to_imx_crtc_state(crtc_state);
202 	struct drm_display_info *di = &conn_state->connector->display_info;
203 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
204 	struct drm_bridge_state *next_bridge_state = NULL;
205 	struct drm_bridge *next_bridge;
206 	u32 bus_flags, bus_fmt;
207 
208 	next_bridge = drm_bridge_get_next_bridge(bridge);
209 	if (next_bridge)
210 		next_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state,
211 								    next_bridge);
212 
213 	if (next_bridge_state)
214 		bus_flags = next_bridge_state->input_bus_cfg.flags;
215 	else if (di->num_bus_formats)
216 		bus_flags = di->bus_flags;
217 	else
218 		bus_flags = imxpd->bus_flags;
219 
220 	bus_fmt = bridge_state->input_bus_cfg.format;
221 	if (!imx_pd_format_supported(bus_fmt))
222 		return -EINVAL;
223 
224 	bridge_state->output_bus_cfg.flags = bus_flags;
225 	bridge_state->input_bus_cfg.flags = bus_flags;
226 	imx_crtc_state->bus_flags = bus_flags;
227 	imx_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
228 	imx_crtc_state->di_hsync_pin = 2;
229 	imx_crtc_state->di_vsync_pin = 3;
230 
231 	return 0;
232 }
233 
234 static const struct drm_connector_funcs imx_pd_connector_funcs = {
235 	.fill_modes = drm_helper_probe_single_connector_modes,
236 	.destroy = imx_drm_connector_destroy,
237 	.reset = drm_atomic_helper_connector_reset,
238 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
239 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
240 };
241 
242 static const struct drm_connector_helper_funcs imx_pd_connector_helper_funcs = {
243 	.get_modes = imx_pd_connector_get_modes,
244 };
245 
246 static const struct drm_bridge_funcs imx_pd_bridge_funcs = {
247 	.enable = imx_pd_bridge_enable,
248 	.disable = imx_pd_bridge_disable,
249 	.atomic_reset = drm_atomic_helper_bridge_reset,
250 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
251 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
252 	.atomic_check = imx_pd_bridge_atomic_check,
253 	.atomic_get_input_bus_fmts = imx_pd_bridge_atomic_get_input_bus_fmts,
254 	.atomic_get_output_bus_fmts = imx_pd_bridge_atomic_get_output_bus_fmts,
255 };
256 
257 static int imx_pd_bind(struct device *dev, struct device *master, void *data)
258 {
259 	struct drm_device *drm = data;
260 	struct imx_parallel_display *imxpd = dev_get_drvdata(dev);
261 	struct imx_parallel_display_encoder *imxpd_encoder;
262 	struct drm_connector *connector;
263 	struct drm_encoder *encoder;
264 	struct drm_bridge *bridge;
265 	int ret;
266 
267 	imxpd_encoder = drmm_simple_encoder_alloc(drm, struct imx_parallel_display_encoder,
268 						  encoder, DRM_MODE_ENCODER_NONE);
269 	if (IS_ERR(imxpd_encoder))
270 		return PTR_ERR(imxpd_encoder);
271 
272 	imxpd_encoder->pd = imxpd;
273 	connector = &imxpd_encoder->connector;
274 	encoder = &imxpd_encoder->encoder;
275 	bridge = &imxpd_encoder->bridge;
276 
277 	ret = imx_drm_encoder_parse_of(drm, encoder, imxpd->dev->of_node);
278 	if (ret)
279 		return ret;
280 
281 	/* set the connector's dpms to OFF so that
282 	 * drm_helper_connector_dpms() won't return
283 	 * immediately since the current state is ON
284 	 * at this point.
285 	 */
286 	connector->dpms = DRM_MODE_DPMS_OFF;
287 
288 	bridge->funcs = &imx_pd_bridge_funcs;
289 	drm_bridge_attach(encoder, bridge, NULL, 0);
290 
291 	if (imxpd->next_bridge) {
292 		ret = drm_bridge_attach(encoder, imxpd->next_bridge, bridge, 0);
293 		if (ret < 0)
294 			return ret;
295 	} else {
296 		drm_connector_helper_add(connector,
297 					 &imx_pd_connector_helper_funcs);
298 		drm_connector_init(drm, connector, &imx_pd_connector_funcs,
299 				   DRM_MODE_CONNECTOR_DPI);
300 
301 		drm_connector_attach_encoder(connector, encoder);
302 	}
303 
304 	return 0;
305 }
306 
307 static const struct component_ops imx_pd_ops = {
308 	.bind	= imx_pd_bind,
309 };
310 
311 static int imx_pd_probe(struct platform_device *pdev)
312 {
313 	struct device *dev = &pdev->dev;
314 	struct device_node *np = dev->of_node;
315 	const u8 *edidp;
316 	struct imx_parallel_display *imxpd;
317 	int edid_len;
318 	int ret;
319 	u32 bus_format = 0;
320 	const char *fmt;
321 
322 	imxpd = devm_kzalloc(dev, sizeof(*imxpd), GFP_KERNEL);
323 	if (!imxpd)
324 		return -ENOMEM;
325 
326 	/* port@1 is the output port */
327 	ret = drm_of_find_panel_or_bridge(np, 1, 0, &imxpd->panel,
328 					  &imxpd->next_bridge);
329 	if (ret && ret != -ENODEV)
330 		return ret;
331 
332 	edidp = of_get_property(np, "edid", &edid_len);
333 	if (edidp)
334 		imxpd->edid = devm_kmemdup(dev, edidp, edid_len, GFP_KERNEL);
335 
336 	ret = of_property_read_string(np, "interface-pix-fmt", &fmt);
337 	if (!ret) {
338 		if (!strcmp(fmt, "rgb24"))
339 			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
340 		else if (!strcmp(fmt, "rgb565"))
341 			bus_format = MEDIA_BUS_FMT_RGB565_1X16;
342 		else if (!strcmp(fmt, "bgr666"))
343 			bus_format = MEDIA_BUS_FMT_RGB666_1X18;
344 		else if (!strcmp(fmt, "lvds666"))
345 			bus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI;
346 	}
347 	imxpd->bus_format = bus_format;
348 
349 	imxpd->dev = dev;
350 
351 	platform_set_drvdata(pdev, imxpd);
352 
353 	return component_add(dev, &imx_pd_ops);
354 }
355 
356 static int imx_pd_remove(struct platform_device *pdev)
357 {
358 	component_del(&pdev->dev, &imx_pd_ops);
359 
360 	return 0;
361 }
362 
363 static const struct of_device_id imx_pd_dt_ids[] = {
364 	{ .compatible = "fsl,imx-parallel-display", },
365 	{ /* sentinel */ }
366 };
367 MODULE_DEVICE_TABLE(of, imx_pd_dt_ids);
368 
369 static struct platform_driver imx_pd_driver = {
370 	.probe		= imx_pd_probe,
371 	.remove		= imx_pd_remove,
372 	.driver		= {
373 		.of_match_table = imx_pd_dt_ids,
374 		.name	= "imx-parallel-display",
375 	},
376 };
377 
378 module_platform_driver(imx_pd_driver);
379 
380 MODULE_DESCRIPTION("i.MX parallel display driver");
381 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
382 MODULE_LICENSE("GPL");
383 MODULE_ALIAS("platform:imx-parallel-display");
384