1 // SPDX-License-Identifier: GPL-2.0+
2 
3 /*
4  * Copyright 2020 NXP
5  */
6 
7 #include <linux/firmware/imx/svc/misc.h>
8 #include <linux/media-bus-format.h>
9 #include <linux/mfd/syscon.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/of_device.h>
13 #include <linux/of_graph.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/regmap.h>
17 
18 #include <drm/drm_atomic_state_helper.h>
19 #include <drm/drm_bridge.h>
20 #include <drm/drm_of.h>
21 #include <drm/drm_print.h>
22 
23 #include <dt-bindings/firmware/imx/rsrc.h>
24 
25 #define PXL2DPI_CTRL	0x40
26 #define  CFG1_16BIT	0x0
27 #define  CFG2_16BIT	0x1
28 #define  CFG3_16BIT	0x2
29 #define  CFG1_18BIT	0x3
30 #define  CFG2_18BIT	0x4
31 #define  CFG_24BIT	0x5
32 
33 #define DRIVER_NAME	"imx8qxp-pxl2dpi"
34 
35 struct imx8qxp_pxl2dpi {
36 	struct regmap *regmap;
37 	struct drm_bridge bridge;
38 	struct drm_bridge *next_bridge;
39 	struct drm_bridge *companion;
40 	struct device *dev;
41 	struct imx_sc_ipc *ipc_handle;
42 	u32 sc_resource;
43 	u32 in_bus_format;
44 	u32 out_bus_format;
45 	u32 pl_sel;
46 };
47 
48 #define bridge_to_p2d(b)	container_of(b, struct imx8qxp_pxl2dpi, bridge)
49 
imx8qxp_pxl2dpi_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)50 static int imx8qxp_pxl2dpi_bridge_attach(struct drm_bridge *bridge,
51 					 enum drm_bridge_attach_flags flags)
52 {
53 	struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
54 
55 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
56 		DRM_DEV_ERROR(p2d->dev,
57 			      "do not support creating a drm_connector\n");
58 		return -EINVAL;
59 	}
60 
61 	return drm_bridge_attach(bridge->encoder,
62 				 p2d->next_bridge, bridge,
63 				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
64 }
65 
66 static int
imx8qxp_pxl2dpi_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)67 imx8qxp_pxl2dpi_bridge_atomic_check(struct drm_bridge *bridge,
68 				    struct drm_bridge_state *bridge_state,
69 				    struct drm_crtc_state *crtc_state,
70 				    struct drm_connector_state *conn_state)
71 {
72 	struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
73 
74 	p2d->in_bus_format = bridge_state->input_bus_cfg.format;
75 	p2d->out_bus_format = bridge_state->output_bus_cfg.format;
76 
77 	return 0;
78 }
79 
80 static void
imx8qxp_pxl2dpi_bridge_mode_set(struct drm_bridge * bridge,const struct drm_display_mode * mode,const struct drm_display_mode * adjusted_mode)81 imx8qxp_pxl2dpi_bridge_mode_set(struct drm_bridge *bridge,
82 				const struct drm_display_mode *mode,
83 				const struct drm_display_mode *adjusted_mode)
84 {
85 	struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
86 	struct imx8qxp_pxl2dpi *companion_p2d;
87 	int ret;
88 
89 	ret = pm_runtime_get_sync(p2d->dev);
90 	if (ret < 0)
91 		DRM_DEV_ERROR(p2d->dev,
92 			      "failed to get runtime PM sync: %d\n", ret);
93 
94 	ret = imx_sc_misc_set_control(p2d->ipc_handle, p2d->sc_resource,
95 				      IMX_SC_C_PXL_LINK_SEL, p2d->pl_sel);
96 	if (ret)
97 		DRM_DEV_ERROR(p2d->dev,
98 			      "failed to set pixel link selection(%u): %d\n",
99 							p2d->pl_sel, ret);
100 
101 	switch (p2d->out_bus_format) {
102 	case MEDIA_BUS_FMT_RGB888_1X24:
103 		regmap_write(p2d->regmap, PXL2DPI_CTRL, CFG_24BIT);
104 		break;
105 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
106 		regmap_write(p2d->regmap, PXL2DPI_CTRL, CFG2_18BIT);
107 		break;
108 	default:
109 		DRM_DEV_ERROR(p2d->dev,
110 			      "unsupported output bus format 0x%08x\n",
111 							p2d->out_bus_format);
112 	}
113 
114 	if (p2d->companion) {
115 		companion_p2d = bridge_to_p2d(p2d->companion);
116 
117 		companion_p2d->in_bus_format = p2d->in_bus_format;
118 		companion_p2d->out_bus_format = p2d->out_bus_format;
119 
120 		p2d->companion->funcs->mode_set(p2d->companion, mode,
121 							adjusted_mode);
122 	}
123 }
124 
imx8qxp_pxl2dpi_bridge_atomic_disable(struct drm_bridge * bridge,struct drm_atomic_state * state)125 static void imx8qxp_pxl2dpi_bridge_atomic_disable(struct drm_bridge *bridge,
126 						  struct drm_atomic_state *state)
127 {
128 	struct imx8qxp_pxl2dpi *p2d = bridge->driver_private;
129 	int ret;
130 
131 	ret = pm_runtime_put(p2d->dev);
132 	if (ret < 0)
133 		DRM_DEV_ERROR(p2d->dev, "failed to put runtime PM: %d\n", ret);
134 
135 	if (p2d->companion)
136 		p2d->companion->funcs->atomic_disable(p2d->companion, state);
137 }
138 
139 static const u32 imx8qxp_pxl2dpi_bus_output_fmts[] = {
140 	MEDIA_BUS_FMT_RGB888_1X24,
141 	MEDIA_BUS_FMT_RGB666_1X24_CPADHI,
142 };
143 
imx8qxp_pxl2dpi_bus_output_fmt_supported(u32 fmt)144 static bool imx8qxp_pxl2dpi_bus_output_fmt_supported(u32 fmt)
145 {
146 	int i;
147 
148 	for (i = 0; i < ARRAY_SIZE(imx8qxp_pxl2dpi_bus_output_fmts); i++) {
149 		if (imx8qxp_pxl2dpi_bus_output_fmts[i] == fmt)
150 			return true;
151 	}
152 
153 	return false;
154 }
155 
156 static u32 *
imx8qxp_pxl2dpi_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)157 imx8qxp_pxl2dpi_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
158 						 struct drm_bridge_state *bridge_state,
159 						 struct drm_crtc_state *crtc_state,
160 						 struct drm_connector_state *conn_state,
161 						 u32 output_fmt,
162 						 unsigned int *num_input_fmts)
163 {
164 	u32 *input_fmts;
165 
166 	if (!imx8qxp_pxl2dpi_bus_output_fmt_supported(output_fmt))
167 		return NULL;
168 
169 	*num_input_fmts = 1;
170 
171 	input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
172 	if (!input_fmts)
173 		return NULL;
174 
175 	switch (output_fmt) {
176 	case MEDIA_BUS_FMT_RGB888_1X24:
177 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
178 		break;
179 	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
180 		input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X36_CPADLO;
181 		break;
182 	default:
183 		kfree(input_fmts);
184 		input_fmts = NULL;
185 		break;
186 	}
187 
188 	return input_fmts;
189 }
190 
191 static u32 *
imx8qxp_pxl2dpi_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)192 imx8qxp_pxl2dpi_bridge_atomic_get_output_bus_fmts(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 						  unsigned int *num_output_fmts)
197 {
198 	*num_output_fmts = ARRAY_SIZE(imx8qxp_pxl2dpi_bus_output_fmts);
199 	return kmemdup(imx8qxp_pxl2dpi_bus_output_fmts,
200 			sizeof(imx8qxp_pxl2dpi_bus_output_fmts), GFP_KERNEL);
201 }
202 
203 static const struct drm_bridge_funcs imx8qxp_pxl2dpi_bridge_funcs = {
204 	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,
205 	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
206 	.atomic_reset		= drm_atomic_helper_bridge_reset,
207 	.attach			= imx8qxp_pxl2dpi_bridge_attach,
208 	.atomic_check		= imx8qxp_pxl2dpi_bridge_atomic_check,
209 	.mode_set		= imx8qxp_pxl2dpi_bridge_mode_set,
210 	.atomic_disable		= imx8qxp_pxl2dpi_bridge_atomic_disable,
211 	.atomic_get_input_bus_fmts =
212 			imx8qxp_pxl2dpi_bridge_atomic_get_input_bus_fmts,
213 	.atomic_get_output_bus_fmts =
214 			imx8qxp_pxl2dpi_bridge_atomic_get_output_bus_fmts,
215 };
216 
217 static struct device_node *
imx8qxp_pxl2dpi_get_available_ep_from_port(struct imx8qxp_pxl2dpi * p2d,u32 port_id)218 imx8qxp_pxl2dpi_get_available_ep_from_port(struct imx8qxp_pxl2dpi *p2d,
219 					   u32 port_id)
220 {
221 	struct device_node *port, *ep;
222 	int ep_cnt;
223 
224 	port = of_graph_get_port_by_id(p2d->dev->of_node, port_id);
225 	if (!port) {
226 		DRM_DEV_ERROR(p2d->dev, "failed to get port@%u\n", port_id);
227 		return ERR_PTR(-ENODEV);
228 	}
229 
230 	ep_cnt = of_get_available_child_count(port);
231 	if (ep_cnt == 0) {
232 		DRM_DEV_ERROR(p2d->dev, "no available endpoints of port@%u\n",
233 			      port_id);
234 		ep = ERR_PTR(-ENODEV);
235 		goto out;
236 	} else if (ep_cnt > 1) {
237 		DRM_DEV_ERROR(p2d->dev,
238 			      "invalid available endpoints of port@%u\n",
239 			      port_id);
240 		ep = ERR_PTR(-EINVAL);
241 		goto out;
242 	}
243 
244 	ep = of_get_next_available_child(port, NULL);
245 	if (!ep) {
246 		DRM_DEV_ERROR(p2d->dev,
247 			      "failed to get available endpoint of port@%u\n",
248 			      port_id);
249 		ep = ERR_PTR(-ENODEV);
250 		goto out;
251 	}
252 out:
253 	of_node_put(port);
254 	return ep;
255 }
256 
257 static struct drm_bridge *
imx8qxp_pxl2dpi_find_next_bridge(struct imx8qxp_pxl2dpi * p2d)258 imx8qxp_pxl2dpi_find_next_bridge(struct imx8qxp_pxl2dpi *p2d)
259 {
260 	struct device_node *ep, *remote;
261 	struct drm_bridge *next_bridge;
262 	int ret;
263 
264 	ep = imx8qxp_pxl2dpi_get_available_ep_from_port(p2d, 1);
265 	if (IS_ERR(ep)) {
266 		ret = PTR_ERR(ep);
267 		return ERR_PTR(ret);
268 	}
269 
270 	remote = of_graph_get_remote_port_parent(ep);
271 	if (!remote || !of_device_is_available(remote)) {
272 		DRM_DEV_ERROR(p2d->dev, "no available remote\n");
273 		next_bridge = ERR_PTR(-ENODEV);
274 		goto out;
275 	} else if (!of_device_is_available(remote->parent)) {
276 		DRM_DEV_ERROR(p2d->dev, "remote parent is not available\n");
277 		next_bridge = ERR_PTR(-ENODEV);
278 		goto out;
279 	}
280 
281 	next_bridge = of_drm_find_bridge(remote);
282 	if (!next_bridge) {
283 		next_bridge = ERR_PTR(-EPROBE_DEFER);
284 		goto out;
285 	}
286 out:
287 	of_node_put(remote);
288 	of_node_put(ep);
289 
290 	return next_bridge;
291 }
292 
imx8qxp_pxl2dpi_set_pixel_link_sel(struct imx8qxp_pxl2dpi * p2d)293 static int imx8qxp_pxl2dpi_set_pixel_link_sel(struct imx8qxp_pxl2dpi *p2d)
294 {
295 	struct device_node *ep;
296 	struct of_endpoint endpoint;
297 	int ret;
298 
299 	ep = imx8qxp_pxl2dpi_get_available_ep_from_port(p2d, 0);
300 	if (IS_ERR(ep))
301 		return PTR_ERR(ep);
302 
303 	ret = of_graph_parse_endpoint(ep, &endpoint);
304 	if (ret) {
305 		DRM_DEV_ERROR(p2d->dev,
306 			      "failed to parse endpoint of port@0: %d\n", ret);
307 		goto out;
308 	}
309 
310 	p2d->pl_sel = endpoint.id;
311 out:
312 	of_node_put(ep);
313 
314 	return ret;
315 }
316 
imx8qxp_pxl2dpi_parse_dt_companion(struct imx8qxp_pxl2dpi * p2d)317 static int imx8qxp_pxl2dpi_parse_dt_companion(struct imx8qxp_pxl2dpi *p2d)
318 {
319 	struct imx8qxp_pxl2dpi *companion_p2d;
320 	struct device *dev = p2d->dev;
321 	struct device_node *companion;
322 	struct device_node *port1, *port2;
323 	const struct of_device_id *match;
324 	int dual_link;
325 	int ret = 0;
326 
327 	/* Locate the companion PXL2DPI for dual-link operation, if any. */
328 	companion = of_parse_phandle(dev->of_node, "fsl,companion-pxl2dpi", 0);
329 	if (!companion)
330 		return 0;
331 
332 	if (!of_device_is_available(companion)) {
333 		DRM_DEV_ERROR(dev, "companion PXL2DPI is not available\n");
334 		ret = -ENODEV;
335 		goto out;
336 	}
337 
338 	/*
339 	 * Sanity check: the companion bridge must have the same compatible
340 	 * string.
341 	 */
342 	match = of_match_device(dev->driver->of_match_table, dev);
343 	if (!of_device_is_compatible(companion, match->compatible)) {
344 		DRM_DEV_ERROR(dev, "companion PXL2DPI is incompatible\n");
345 		ret = -ENXIO;
346 		goto out;
347 	}
348 
349 	p2d->companion = of_drm_find_bridge(companion);
350 	if (!p2d->companion) {
351 		ret = -EPROBE_DEFER;
352 		DRM_DEV_DEBUG_DRIVER(p2d->dev,
353 				     "failed to find companion bridge: %d\n",
354 				     ret);
355 		goto out;
356 	}
357 
358 	companion_p2d = bridge_to_p2d(p2d->companion);
359 
360 	/*
361 	 * We need to work out if the sink is expecting us to function in
362 	 * dual-link mode.  We do this by looking at the DT port nodes that
363 	 * the next bridges are connected to.  If they are marked as expecting
364 	 * even pixels and odd pixels than we need to use the companion PXL2DPI.
365 	 */
366 	port1 = of_graph_get_port_by_id(p2d->next_bridge->of_node, 1);
367 	port2 = of_graph_get_port_by_id(companion_p2d->next_bridge->of_node, 1);
368 	dual_link = drm_of_lvds_get_dual_link_pixel_order(port1, port2);
369 	of_node_put(port1);
370 	of_node_put(port2);
371 
372 	if (dual_link < 0) {
373 		ret = dual_link;
374 		DRM_DEV_ERROR(dev, "failed to get dual link pixel order: %d\n",
375 			      ret);
376 		goto out;
377 	}
378 
379 	DRM_DEV_DEBUG_DRIVER(dev,
380 			     "dual-link configuration detected (companion bridge %pOF)\n",
381 			     companion);
382 out:
383 	of_node_put(companion);
384 	return ret;
385 }
386 
imx8qxp_pxl2dpi_bridge_probe(struct platform_device * pdev)387 static int imx8qxp_pxl2dpi_bridge_probe(struct platform_device *pdev)
388 {
389 	struct imx8qxp_pxl2dpi *p2d;
390 	struct device *dev = &pdev->dev;
391 	struct device_node *np = dev->of_node;
392 	int ret;
393 
394 	p2d = devm_kzalloc(dev, sizeof(*p2d), GFP_KERNEL);
395 	if (!p2d)
396 		return -ENOMEM;
397 
398 	p2d->regmap = syscon_node_to_regmap(np->parent);
399 	if (IS_ERR(p2d->regmap)) {
400 		ret = PTR_ERR(p2d->regmap);
401 		if (ret != -EPROBE_DEFER)
402 			DRM_DEV_ERROR(dev, "failed to get regmap: %d\n", ret);
403 		return ret;
404 	}
405 
406 	ret = imx_scu_get_handle(&p2d->ipc_handle);
407 	if (ret) {
408 		if (ret != -EPROBE_DEFER)
409 			DRM_DEV_ERROR(dev, "failed to get SCU ipc handle: %d\n",
410 				      ret);
411 		return ret;
412 	}
413 
414 	p2d->dev = dev;
415 
416 	ret = of_property_read_u32(np, "fsl,sc-resource", &p2d->sc_resource);
417 	if (ret) {
418 		DRM_DEV_ERROR(dev, "failed to get SC resource %d\n", ret);
419 		return ret;
420 	}
421 
422 	p2d->next_bridge = imx8qxp_pxl2dpi_find_next_bridge(p2d);
423 	if (IS_ERR(p2d->next_bridge)) {
424 		ret = PTR_ERR(p2d->next_bridge);
425 		if (ret != -EPROBE_DEFER)
426 			DRM_DEV_ERROR(dev, "failed to find next bridge: %d\n",
427 				      ret);
428 		return ret;
429 	}
430 
431 	ret = imx8qxp_pxl2dpi_set_pixel_link_sel(p2d);
432 	if (ret)
433 		return ret;
434 
435 	ret = imx8qxp_pxl2dpi_parse_dt_companion(p2d);
436 	if (ret)
437 		return ret;
438 
439 	platform_set_drvdata(pdev, p2d);
440 	pm_runtime_enable(dev);
441 
442 	p2d->bridge.driver_private = p2d;
443 	p2d->bridge.funcs = &imx8qxp_pxl2dpi_bridge_funcs;
444 	p2d->bridge.of_node = np;
445 
446 	drm_bridge_add(&p2d->bridge);
447 
448 	return ret;
449 }
450 
imx8qxp_pxl2dpi_bridge_remove(struct platform_device * pdev)451 static void imx8qxp_pxl2dpi_bridge_remove(struct platform_device *pdev)
452 {
453 	struct imx8qxp_pxl2dpi *p2d = platform_get_drvdata(pdev);
454 
455 	drm_bridge_remove(&p2d->bridge);
456 
457 	pm_runtime_disable(&pdev->dev);
458 }
459 
460 static const struct of_device_id imx8qxp_pxl2dpi_dt_ids[] = {
461 	{ .compatible = "fsl,imx8qxp-pxl2dpi", },
462 	{ /* sentinel */ }
463 };
464 MODULE_DEVICE_TABLE(of, imx8qxp_pxl2dpi_dt_ids);
465 
466 static struct platform_driver imx8qxp_pxl2dpi_bridge_driver = {
467 	.probe	= imx8qxp_pxl2dpi_bridge_probe,
468 	.remove = imx8qxp_pxl2dpi_bridge_remove,
469 	.driver	= {
470 		.of_match_table = imx8qxp_pxl2dpi_dt_ids,
471 		.name = DRIVER_NAME,
472 	},
473 };
474 module_platform_driver(imx8qxp_pxl2dpi_bridge_driver);
475 
476 MODULE_DESCRIPTION("i.MX8QXP pixel link to DPI bridge driver");
477 MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
478 MODULE_LICENSE("GPL v2");
479 MODULE_ALIAS("platform:" DRIVER_NAME);
480