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/module.h>
10 #include <linux/platform_device.h>
11 #include <linux/videodev2.h>
12 
13 #include <video/of_display_timing.h>
14 
15 #include <drm/drm_atomic_helper.h>
16 #include <drm/drm_bridge.h>
17 #include <drm/drm_fb_helper.h>
18 #include <drm/drm_managed.h>
19 #include <drm/drm_of.h>
20 #include <drm/drm_panel.h>
21 #include <drm/drm_probe_helper.h>
22 #include <drm/drm_simple_kms_helper.h>
23 
24 #include "imx-drm.h"
25 
26 struct imx_parallel_display_encoder {
27 	struct drm_connector connector;
28 	struct drm_encoder encoder;
29 	struct drm_bridge bridge;
30 	struct imx_parallel_display *pd;
31 };
32 
33 struct imx_parallel_display {
34 	struct device *dev;
35 	void *edid;
36 	u32 bus_format;
37 	u32 bus_flags;
38 	struct drm_display_mode mode;
39 	struct drm_panel *panel;
40 	struct drm_bridge *next_bridge;
41 };
42 
con_to_imxpd(struct drm_connector * c)43 static inline struct imx_parallel_display *con_to_imxpd(struct drm_connector *c)
44 {
45 	return container_of(c, struct imx_parallel_display_encoder, connector)->pd;
46 }
47 
bridge_to_imxpd(struct drm_bridge * b)48 static inline struct imx_parallel_display *bridge_to_imxpd(struct drm_bridge *b)
49 {
50 	return container_of(b, struct imx_parallel_display_encoder, bridge)->pd;
51 }
52 
imx_pd_connector_get_modes(struct drm_connector * connector)53 static int imx_pd_connector_get_modes(struct drm_connector *connector)
54 {
55 	struct imx_parallel_display *imxpd = con_to_imxpd(connector);
56 	struct device_node *np = imxpd->dev->of_node;
57 	int num_modes;
58 
59 	num_modes = drm_panel_get_modes(imxpd->panel, connector);
60 	if (num_modes > 0)
61 		return num_modes;
62 
63 	if (imxpd->edid) {
64 		drm_connector_update_edid_property(connector, imxpd->edid);
65 		num_modes = drm_add_edid_modes(connector, imxpd->edid);
66 	}
67 
68 	if (np) {
69 		struct drm_display_mode *mode = drm_mode_create(connector->dev);
70 		int ret;
71 
72 		if (!mode)
73 			return -EINVAL;
74 
75 		ret = of_get_drm_display_mode(np, &imxpd->mode,
76 					      &imxpd->bus_flags,
77 					      OF_USE_NATIVE_MODE);
78 		if (ret)
79 			return ret;
80 
81 		drm_mode_copy(mode, &imxpd->mode);
82 		mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
83 		drm_mode_probed_add(connector, mode);
84 		num_modes++;
85 	}
86 
87 	return num_modes;
88 }
89 
imx_pd_bridge_enable(struct drm_bridge * bridge)90 static void imx_pd_bridge_enable(struct drm_bridge *bridge)
91 {
92 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
93 
94 	drm_panel_prepare(imxpd->panel);
95 	drm_panel_enable(imxpd->panel);
96 }
97 
imx_pd_bridge_disable(struct drm_bridge * bridge)98 static void imx_pd_bridge_disable(struct drm_bridge *bridge)
99 {
100 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
101 
102 	drm_panel_disable(imxpd->panel);
103 	drm_panel_unprepare(imxpd->panel);
104 }
105 
106 static const u32 imx_pd_bus_fmts[] = {
107 	MEDIA_BUS_FMT_RGB888_1X24,
108 	MEDIA_BUS_FMT_BGR888_1X24,
109 	MEDIA_BUS_FMT_GBR888_1X24,
110 	MEDIA_BUS_FMT_RGB666_1X18,
111 	MEDIA_BUS_FMT_RGB666_1X24_CPADHI,
112 	MEDIA_BUS_FMT_RGB565_1X16,
113 };
114 
115 static u32 *
imx_pd_bridge_atomic_get_output_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,unsigned int * num_output_fmts)116 imx_pd_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
117 					 struct drm_bridge_state *bridge_state,
118 					 struct drm_crtc_state *crtc_state,
119 					 struct drm_connector_state *conn_state,
120 					 unsigned int *num_output_fmts)
121 {
122 	struct drm_display_info *di = &conn_state->connector->display_info;
123 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
124 	u32 *output_fmts;
125 
126 	if (!imxpd->bus_format && !di->num_bus_formats) {
127 		*num_output_fmts = ARRAY_SIZE(imx_pd_bus_fmts);
128 		return kmemdup(imx_pd_bus_fmts, sizeof(imx_pd_bus_fmts),
129 			       GFP_KERNEL);
130 	}
131 
132 	*num_output_fmts = 1;
133 	output_fmts = kmalloc(sizeof(*output_fmts), GFP_KERNEL);
134 	if (!output_fmts)
135 		return NULL;
136 
137 	if (!imxpd->bus_format && di->num_bus_formats)
138 		output_fmts[0] = di->bus_formats[0];
139 	else
140 		output_fmts[0] = imxpd->bus_format;
141 
142 	return output_fmts;
143 }
144 
imx_pd_format_supported(u32 output_fmt)145 static bool imx_pd_format_supported(u32 output_fmt)
146 {
147 	unsigned int i;
148 
149 	for (i = 0; i < ARRAY_SIZE(imx_pd_bus_fmts); i++) {
150 		if (imx_pd_bus_fmts[i] == output_fmt)
151 			return true;
152 	}
153 
154 	return false;
155 }
156 
157 static u32 *
imx_pd_bridge_atomic_get_input_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,u32 output_fmt,unsigned int * num_input_fmts)158 imx_pd_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
159 					struct drm_bridge_state *bridge_state,
160 					struct drm_crtc_state *crtc_state,
161 					struct drm_connector_state *conn_state,
162 					u32 output_fmt,
163 					unsigned int *num_input_fmts)
164 {
165 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
166 	u32 *input_fmts;
167 
168 	/*
169 	 * If the next bridge does not support bus format negotiation, let's
170 	 * use the static bus format definition (imxpd->bus_format) if it's
171 	 * specified, RGB888 when it's not.
172 	 */
173 	if (output_fmt == MEDIA_BUS_FMT_FIXED)
174 		output_fmt = imxpd->bus_format ? : MEDIA_BUS_FMT_RGB888_1X24;
175 
176 	/* Now make sure the requested output format is supported. */
177 	if ((imxpd->bus_format && imxpd->bus_format != output_fmt) ||
178 	    !imx_pd_format_supported(output_fmt)) {
179 		*num_input_fmts = 0;
180 		return NULL;
181 	}
182 
183 	*num_input_fmts = 1;
184 	input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
185 	if (!input_fmts)
186 		return NULL;
187 
188 	input_fmts[0] = output_fmt;
189 	return input_fmts;
190 }
191 
imx_pd_bridge_atomic_check(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state)192 static int imx_pd_bridge_atomic_check(struct drm_bridge *bridge,
193 				      struct drm_bridge_state *bridge_state,
194 				      struct drm_crtc_state *crtc_state,
195 				      struct drm_connector_state *conn_state)
196 {
197 	struct imx_crtc_state *imx_crtc_state = to_imx_crtc_state(crtc_state);
198 	struct drm_display_info *di = &conn_state->connector->display_info;
199 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
200 	struct drm_bridge_state *next_bridge_state = NULL;
201 	struct drm_bridge *next_bridge;
202 	u32 bus_flags, bus_fmt;
203 
204 	next_bridge = drm_bridge_get_next_bridge(bridge);
205 	if (next_bridge)
206 		next_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state,
207 								    next_bridge);
208 
209 	if (next_bridge_state)
210 		bus_flags = next_bridge_state->input_bus_cfg.flags;
211 	else if (di->num_bus_formats)
212 		bus_flags = di->bus_flags;
213 	else
214 		bus_flags = imxpd->bus_flags;
215 
216 	bus_fmt = bridge_state->input_bus_cfg.format;
217 	if (!imx_pd_format_supported(bus_fmt))
218 		return -EINVAL;
219 
220 	if (bus_flags &
221 	    ~(DRM_BUS_FLAG_DE_LOW | DRM_BUS_FLAG_DE_HIGH |
222 	      DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE |
223 	      DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)) {
224 		dev_warn(imxpd->dev, "invalid bus_flags (%x)\n", bus_flags);
225 		return -EINVAL;
226 	}
227 
228 	bridge_state->output_bus_cfg.flags = bus_flags;
229 	bridge_state->input_bus_cfg.flags = bus_flags;
230 	imx_crtc_state->bus_flags = bus_flags;
231 	imx_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
232 	imx_crtc_state->di_hsync_pin = 2;
233 	imx_crtc_state->di_vsync_pin = 3;
234 
235 	return 0;
236 }
237 
238 static const struct drm_connector_funcs imx_pd_connector_funcs = {
239 	.fill_modes = drm_helper_probe_single_connector_modes,
240 	.destroy = imx_drm_connector_destroy,
241 	.reset = drm_atomic_helper_connector_reset,
242 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
243 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
244 };
245 
246 static const struct drm_connector_helper_funcs imx_pd_connector_helper_funcs = {
247 	.get_modes = imx_pd_connector_get_modes,
248 };
249 
250 static const struct drm_bridge_funcs imx_pd_bridge_funcs = {
251 	.enable = imx_pd_bridge_enable,
252 	.disable = imx_pd_bridge_disable,
253 	.atomic_reset = drm_atomic_helper_bridge_reset,
254 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
255 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
256 	.atomic_check = imx_pd_bridge_atomic_check,
257 	.atomic_get_input_bus_fmts = imx_pd_bridge_atomic_get_input_bus_fmts,
258 	.atomic_get_output_bus_fmts = imx_pd_bridge_atomic_get_output_bus_fmts,
259 };
260 
imx_pd_bind(struct device * dev,struct device * master,void * data)261 static int imx_pd_bind(struct device *dev, struct device *master, void *data)
262 {
263 	struct drm_device *drm = data;
264 	struct imx_parallel_display *imxpd = dev_get_drvdata(dev);
265 	struct imx_parallel_display_encoder *imxpd_encoder;
266 	struct drm_connector *connector;
267 	struct drm_encoder *encoder;
268 	struct drm_bridge *bridge;
269 	int ret;
270 
271 	imxpd_encoder = drmm_simple_encoder_alloc(drm, struct imx_parallel_display_encoder,
272 						  encoder, DRM_MODE_ENCODER_NONE);
273 	if (IS_ERR(imxpd_encoder))
274 		return PTR_ERR(imxpd_encoder);
275 
276 	imxpd_encoder->pd = imxpd;
277 	connector = &imxpd_encoder->connector;
278 	encoder = &imxpd_encoder->encoder;
279 	bridge = &imxpd_encoder->bridge;
280 
281 	ret = imx_drm_encoder_parse_of(drm, encoder, imxpd->dev->of_node);
282 	if (ret)
283 		return ret;
284 
285 	/* set the connector's dpms to OFF so that
286 	 * drm_helper_connector_dpms() won't return
287 	 * immediately since the current state is ON
288 	 * at this point.
289 	 */
290 	connector->dpms = DRM_MODE_DPMS_OFF;
291 
292 	bridge->funcs = &imx_pd_bridge_funcs;
293 	drm_bridge_attach(encoder, bridge, NULL, 0);
294 
295 	if (imxpd->next_bridge) {
296 		ret = drm_bridge_attach(encoder, imxpd->next_bridge, bridge, 0);
297 		if (ret < 0)
298 			return ret;
299 	} else {
300 		drm_connector_helper_add(connector,
301 					 &imx_pd_connector_helper_funcs);
302 		drm_connector_init(drm, connector, &imx_pd_connector_funcs,
303 				   DRM_MODE_CONNECTOR_DPI);
304 
305 		drm_connector_attach_encoder(connector, encoder);
306 	}
307 
308 	return 0;
309 }
310 
311 static const struct component_ops imx_pd_ops = {
312 	.bind	= imx_pd_bind,
313 };
314 
imx_pd_probe(struct platform_device * pdev)315 static int imx_pd_probe(struct platform_device *pdev)
316 {
317 	struct device *dev = &pdev->dev;
318 	struct device_node *np = dev->of_node;
319 	const u8 *edidp;
320 	struct imx_parallel_display *imxpd;
321 	int edid_len;
322 	int ret;
323 	u32 bus_format = 0;
324 	const char *fmt;
325 
326 	imxpd = devm_kzalloc(dev, sizeof(*imxpd), GFP_KERNEL);
327 	if (!imxpd)
328 		return -ENOMEM;
329 
330 	/* port@1 is the output port */
331 	ret = drm_of_find_panel_or_bridge(np, 1, 0, &imxpd->panel,
332 					  &imxpd->next_bridge);
333 	if (ret && ret != -ENODEV)
334 		return ret;
335 
336 	edidp = of_get_property(np, "edid", &edid_len);
337 	if (edidp)
338 		imxpd->edid = devm_kmemdup(dev, edidp, edid_len, GFP_KERNEL);
339 
340 	ret = of_property_read_string(np, "interface-pix-fmt", &fmt);
341 	if (!ret) {
342 		if (!strcmp(fmt, "rgb24"))
343 			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
344 		else if (!strcmp(fmt, "rgb565"))
345 			bus_format = MEDIA_BUS_FMT_RGB565_1X16;
346 		else if (!strcmp(fmt, "bgr666"))
347 			bus_format = MEDIA_BUS_FMT_RGB666_1X18;
348 		else if (!strcmp(fmt, "lvds666"))
349 			bus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI;
350 	}
351 	imxpd->bus_format = bus_format;
352 
353 	imxpd->dev = dev;
354 
355 	platform_set_drvdata(pdev, imxpd);
356 
357 	return component_add(dev, &imx_pd_ops);
358 }
359 
imx_pd_remove(struct platform_device * pdev)360 static int imx_pd_remove(struct platform_device *pdev)
361 {
362 	component_del(&pdev->dev, &imx_pd_ops);
363 
364 	return 0;
365 }
366 
367 static const struct of_device_id imx_pd_dt_ids[] = {
368 	{ .compatible = "fsl,imx-parallel-display", },
369 	{ /* sentinel */ }
370 };
371 MODULE_DEVICE_TABLE(of, imx_pd_dt_ids);
372 
373 static struct platform_driver imx_pd_driver = {
374 	.probe		= imx_pd_probe,
375 	.remove		= imx_pd_remove,
376 	.driver		= {
377 		.of_match_table = imx_pd_dt_ids,
378 		.name	= "imx-parallel-display",
379 	},
380 };
381 
382 module_platform_driver(imx_pd_driver);
383 
384 MODULE_DESCRIPTION("i.MX parallel display driver");
385 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
386 MODULE_LICENSE("GPL");
387 MODULE_ALIAS("platform:imx-parallel-display");
388