xref: /linux/drivers/gpu/drm/imx/ipuv3/parallel-display.c (revision 40286d6379aacfcc053253ef78dc78b09addffda)
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 <drm/drm_atomic_helper.h>
16 #include <drm/drm_bridge.h>
17 #include <drm/drm_bridge_connector.h>
18 #include <drm/drm_managed.h>
19 #include <drm/drm_of.h>
20 #include <drm/drm_probe_helper.h>
21 #include <drm/drm_simple_kms_helper.h>
22 #include <drm/bridge/imx.h>
23 
24 #include "imx-drm.h"
25 
26 struct imx_parallel_display_encoder {
27 	struct drm_encoder encoder;
28 };
29 
30 struct imx_parallel_display {
31 	struct device *dev;
32 	u32 bus_format;
33 	struct drm_bridge *next_bridge;
34 	struct drm_bridge bridge;
35 };
36 
37 static inline struct imx_parallel_display *bridge_to_imxpd(struct drm_bridge *b)
38 {
39 	return container_of(b, struct imx_parallel_display, bridge);
40 }
41 
42 static const u32 imx_pd_bus_fmts[] = {
43 	MEDIA_BUS_FMT_RGB888_1X24,
44 	MEDIA_BUS_FMT_BGR888_1X24,
45 	MEDIA_BUS_FMT_GBR888_1X24,
46 	MEDIA_BUS_FMT_RGB666_1X18,
47 	MEDIA_BUS_FMT_RGB666_1X24_CPADHI,
48 	MEDIA_BUS_FMT_RGB565_1X16,
49 };
50 
51 static u32 *
52 imx_pd_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
53 					 struct drm_bridge_state *bridge_state,
54 					 struct drm_crtc_state *crtc_state,
55 					 struct drm_connector_state *conn_state,
56 					 unsigned int *num_output_fmts)
57 {
58 	struct drm_display_info *di = &conn_state->connector->display_info;
59 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
60 	u32 *output_fmts;
61 
62 	if (!imxpd->bus_format && !di->num_bus_formats) {
63 		*num_output_fmts = ARRAY_SIZE(imx_pd_bus_fmts);
64 		return kmemdup(imx_pd_bus_fmts, sizeof(imx_pd_bus_fmts),
65 			       GFP_KERNEL);
66 	}
67 
68 	*num_output_fmts = 1;
69 	output_fmts = kmalloc_obj(*output_fmts);
70 	if (!output_fmts)
71 		return NULL;
72 
73 	if (!imxpd->bus_format && di->num_bus_formats)
74 		output_fmts[0] = di->bus_formats[0];
75 	else
76 		output_fmts[0] = imxpd->bus_format;
77 
78 	return output_fmts;
79 }
80 
81 static bool imx_pd_format_supported(u32 output_fmt)
82 {
83 	unsigned int i;
84 
85 	for (i = 0; i < ARRAY_SIZE(imx_pd_bus_fmts); i++) {
86 		if (imx_pd_bus_fmts[i] == output_fmt)
87 			return true;
88 	}
89 
90 	return false;
91 }
92 
93 static u32 *
94 imx_pd_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
95 					struct drm_bridge_state *bridge_state,
96 					struct drm_crtc_state *crtc_state,
97 					struct drm_connector_state *conn_state,
98 					u32 output_fmt,
99 					unsigned int *num_input_fmts)
100 {
101 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
102 	u32 *input_fmts;
103 
104 	/*
105 	 * If the next bridge does not support bus format negotiation, let's
106 	 * use the static bus format definition (imxpd->bus_format) if it's
107 	 * specified, RGB888 when it's not.
108 	 */
109 	if (output_fmt == MEDIA_BUS_FMT_FIXED)
110 		output_fmt = imxpd->bus_format ? : MEDIA_BUS_FMT_RGB888_1X24;
111 
112 	/* Now make sure the requested output format is supported. */
113 	if (!imx_pd_format_supported(output_fmt)) {
114 		*num_input_fmts = 0;
115 		return NULL;
116 	}
117 
118 	*num_input_fmts = 1;
119 	input_fmts = kmalloc_obj(*input_fmts);
120 	if (!input_fmts)
121 		return NULL;
122 
123 	/*
124 	 * Prefer bus format set via legacy "interface-pix-fmt" DT property
125 	 * over panel bus format. This is necessary to retain support for
126 	 * DTs which configure the IPUv3 parallel output as 24bit, but
127 	 * connect 18bit DPI panels to it with hardware swizzling.
128 	 */
129 	if (imxpd->bus_format && imxpd->bus_format != output_fmt)
130 		input_fmts[0] = imxpd->bus_format;
131 	else
132 		input_fmts[0] = output_fmt;
133 
134 	return input_fmts;
135 }
136 
137 static int imx_pd_bridge_atomic_check(struct drm_bridge *bridge,
138 				      struct drm_bridge_state *bridge_state,
139 				      struct drm_crtc_state *crtc_state,
140 				      struct drm_connector_state *conn_state)
141 {
142 	struct imx_crtc_state *imx_crtc_state = to_imx_crtc_state(crtc_state);
143 	struct drm_display_info *di = &conn_state->connector->display_info;
144 	struct drm_bridge_state *next_bridge_state = NULL;
145 	u32 bus_flags, bus_fmt;
146 
147 	struct drm_bridge *next_bridge __free(drm_bridge_put) = drm_bridge_get_next_bridge(bridge);
148 
149 	if (next_bridge)
150 		next_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state,
151 								    next_bridge);
152 
153 	if (next_bridge_state)
154 		bus_flags = next_bridge_state->input_bus_cfg.flags;
155 	else
156 		bus_flags = di->bus_flags;
157 
158 	bus_fmt = bridge_state->input_bus_cfg.format;
159 	if (!imx_pd_format_supported(bus_fmt))
160 		return -EINVAL;
161 
162 	bridge_state->output_bus_cfg.flags = bus_flags;
163 	bridge_state->input_bus_cfg.flags = bus_flags;
164 	imx_crtc_state->bus_flags = bus_flags;
165 	imx_crtc_state->bus_format = bridge_state->input_bus_cfg.format;
166 	imx_crtc_state->di_hsync_pin = 2;
167 	imx_crtc_state->di_vsync_pin = 3;
168 
169 	return 0;
170 }
171 
172 static int imx_pd_bridge_attach(struct drm_bridge *bridge,
173 				struct drm_encoder *encoder,
174 				enum drm_bridge_attach_flags flags)
175 {
176 	struct imx_parallel_display *imxpd = bridge_to_imxpd(bridge);
177 
178 	return drm_bridge_attach(encoder, imxpd->next_bridge, bridge, flags);
179 }
180 
181 static const struct drm_bridge_funcs imx_pd_bridge_funcs = {
182 	.attach = imx_pd_bridge_attach,
183 	.atomic_reset = drm_atomic_helper_bridge_reset,
184 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
185 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
186 	.atomic_check = imx_pd_bridge_atomic_check,
187 	.atomic_get_input_bus_fmts = imx_pd_bridge_atomic_get_input_bus_fmts,
188 	.atomic_get_output_bus_fmts = imx_pd_bridge_atomic_get_output_bus_fmts,
189 };
190 
191 static int imx_pd_bind(struct device *dev, struct device *master, void *data)
192 {
193 	struct drm_device *drm = data;
194 	struct imx_parallel_display *imxpd = dev_get_drvdata(dev);
195 	struct imx_parallel_display_encoder *imxpd_encoder;
196 	struct drm_connector *connector;
197 	struct drm_encoder *encoder;
198 	struct drm_bridge *bridge;
199 	int ret;
200 
201 	imxpd_encoder = drmm_simple_encoder_alloc(drm, struct imx_parallel_display_encoder,
202 						  encoder, DRM_MODE_ENCODER_NONE);
203 	if (IS_ERR(imxpd_encoder))
204 		return PTR_ERR(imxpd_encoder);
205 
206 	encoder = &imxpd_encoder->encoder;
207 	bridge = &imxpd->bridge;
208 
209 	ret = imx_drm_encoder_parse_of(drm, encoder, imxpd->dev->of_node);
210 	if (ret)
211 		return ret;
212 
213 	drm_bridge_attach(encoder, bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR);
214 
215 	connector = drm_bridge_connector_init(drm, encoder);
216 	if (IS_ERR(connector))
217 		return PTR_ERR(connector);
218 
219 	drm_connector_attach_encoder(connector, encoder);
220 
221 	return 0;
222 }
223 
224 static const struct component_ops imx_pd_ops = {
225 	.bind	= imx_pd_bind,
226 };
227 
228 static int imx_pd_probe(struct platform_device *pdev)
229 {
230 	struct device *dev = &pdev->dev;
231 	struct device_node *np = dev->of_node;
232 	struct imx_parallel_display *imxpd;
233 	int ret;
234 	u32 bus_format = 0;
235 	const char *fmt;
236 
237 	imxpd = devm_drm_bridge_alloc(dev, struct imx_parallel_display, bridge,
238 				      &imx_pd_bridge_funcs);
239 	if (IS_ERR(imxpd))
240 		return PTR_ERR(imxpd);
241 
242 	/* port@1 is the output port */
243 	imxpd->next_bridge = devm_drm_of_get_bridge(dev, np, 1, 0);
244 	if (imxpd->next_bridge == ERR_PTR(-ENODEV))
245 		imxpd->next_bridge = devm_imx_drm_legacy_bridge(dev, np, DRM_MODE_CONNECTOR_DPI);
246 	if (IS_ERR(imxpd->next_bridge)) {
247 		ret = PTR_ERR(imxpd->next_bridge);
248 		return ret;
249 	}
250 
251 	ret = of_property_read_string(np, "interface-pix-fmt", &fmt);
252 	if (!ret) {
253 		if (!strcmp(fmt, "rgb24"))
254 			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
255 		else if (!strcmp(fmt, "rgb565"))
256 			bus_format = MEDIA_BUS_FMT_RGB565_1X16;
257 		else if (!strcmp(fmt, "bgr666"))
258 			bus_format = MEDIA_BUS_FMT_RGB666_1X18;
259 		else if (!strcmp(fmt, "lvds666"))
260 			bus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI;
261 	}
262 	imxpd->bus_format = bus_format;
263 
264 	imxpd->dev = dev;
265 
266 	platform_set_drvdata(pdev, imxpd);
267 
268 	ret = devm_drm_bridge_add(dev, &imxpd->bridge);
269 	if (ret)
270 		return ret;
271 
272 	return component_add(dev, &imx_pd_ops);
273 }
274 
275 static void imx_pd_remove(struct platform_device *pdev)
276 {
277 	component_del(&pdev->dev, &imx_pd_ops);
278 }
279 
280 static const struct of_device_id imx_pd_dt_ids[] = {
281 	{ .compatible = "fsl,imx-parallel-display", },
282 	{ /* sentinel */ }
283 };
284 MODULE_DEVICE_TABLE(of, imx_pd_dt_ids);
285 
286 static struct platform_driver imx_pd_driver = {
287 	.probe		= imx_pd_probe,
288 	.remove		= imx_pd_remove,
289 	.driver		= {
290 		.of_match_table = imx_pd_dt_ids,
291 		.name	= "imx-parallel-display",
292 	},
293 };
294 
295 module_platform_driver(imx_pd_driver);
296 
297 MODULE_DESCRIPTION("i.MX parallel display driver");
298 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
299 MODULE_LICENSE("GPL");
300