1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Generic DVI Connector driver
4 *
5 * Copyright (C) 2013 Texas Instruments
6 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
7 */
8
9 #include <linux/i2c.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/slab.h>
13
14 #include <drm/drm_edid.h>
15
16 #include <video/omapfb_dss.h>
17
18 static const struct omap_video_timings dvic_default_timings = {
19 .x_res = 640,
20 .y_res = 480,
21
22 .pixelclock = 23500000,
23
24 .hfp = 48,
25 .hsw = 32,
26 .hbp = 80,
27
28 .vfp = 3,
29 .vsw = 4,
30 .vbp = 7,
31
32 .vsync_level = OMAPDSS_SIG_ACTIVE_HIGH,
33 .hsync_level = OMAPDSS_SIG_ACTIVE_HIGH,
34 .data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE,
35 .de_level = OMAPDSS_SIG_ACTIVE_HIGH,
36 .sync_pclk_edge = OMAPDSS_DRIVE_SIG_FALLING_EDGE,
37 };
38
39 struct panel_drv_data {
40 struct omap_dss_device dssdev;
41 struct omap_dss_device *in;
42
43 struct omap_video_timings timings;
44
45 struct i2c_adapter *i2c_adapter;
46 };
47
48 #define to_panel_data(x) container_of(x, struct panel_drv_data, dssdev)
49
dvic_connect(struct omap_dss_device * dssdev)50 static int dvic_connect(struct omap_dss_device *dssdev)
51 {
52 struct panel_drv_data *ddata = to_panel_data(dssdev);
53 struct omap_dss_device *in = ddata->in;
54
55 if (omapdss_device_is_connected(dssdev))
56 return 0;
57
58 return in->ops.dvi->connect(in, dssdev);
59 }
60
dvic_disconnect(struct omap_dss_device * dssdev)61 static void dvic_disconnect(struct omap_dss_device *dssdev)
62 {
63 struct panel_drv_data *ddata = to_panel_data(dssdev);
64 struct omap_dss_device *in = ddata->in;
65
66 if (!omapdss_device_is_connected(dssdev))
67 return;
68
69 in->ops.dvi->disconnect(in, dssdev);
70 }
71
dvic_enable(struct omap_dss_device * dssdev)72 static int dvic_enable(struct omap_dss_device *dssdev)
73 {
74 struct panel_drv_data *ddata = to_panel_data(dssdev);
75 struct omap_dss_device *in = ddata->in;
76 int r;
77
78 if (!omapdss_device_is_connected(dssdev))
79 return -ENODEV;
80
81 if (omapdss_device_is_enabled(dssdev))
82 return 0;
83
84 in->ops.dvi->set_timings(in, &ddata->timings);
85
86 r = in->ops.dvi->enable(in);
87 if (r)
88 return r;
89
90 dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
91
92 return 0;
93 }
94
dvic_disable(struct omap_dss_device * dssdev)95 static void dvic_disable(struct omap_dss_device *dssdev)
96 {
97 struct panel_drv_data *ddata = to_panel_data(dssdev);
98 struct omap_dss_device *in = ddata->in;
99
100 if (!omapdss_device_is_enabled(dssdev))
101 return;
102
103 in->ops.dvi->disable(in);
104
105 dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
106 }
107
dvic_set_timings(struct omap_dss_device * dssdev,struct omap_video_timings * timings)108 static void dvic_set_timings(struct omap_dss_device *dssdev,
109 struct omap_video_timings *timings)
110 {
111 struct panel_drv_data *ddata = to_panel_data(dssdev);
112 struct omap_dss_device *in = ddata->in;
113
114 ddata->timings = *timings;
115 dssdev->panel.timings = *timings;
116
117 in->ops.dvi->set_timings(in, timings);
118 }
119
dvic_get_timings(struct omap_dss_device * dssdev,struct omap_video_timings * timings)120 static void dvic_get_timings(struct omap_dss_device *dssdev,
121 struct omap_video_timings *timings)
122 {
123 struct panel_drv_data *ddata = to_panel_data(dssdev);
124
125 *timings = ddata->timings;
126 }
127
dvic_check_timings(struct omap_dss_device * dssdev,struct omap_video_timings * timings)128 static int dvic_check_timings(struct omap_dss_device *dssdev,
129 struct omap_video_timings *timings)
130 {
131 struct panel_drv_data *ddata = to_panel_data(dssdev);
132 struct omap_dss_device *in = ddata->in;
133
134 return in->ops.dvi->check_timings(in, timings);
135 }
136
dvic_ddc_read(struct i2c_adapter * adapter,unsigned char * buf,u16 count,u8 offset)137 static int dvic_ddc_read(struct i2c_adapter *adapter,
138 unsigned char *buf, u16 count, u8 offset)
139 {
140 int r, retries;
141
142 for (retries = 3; retries > 0; retries--) {
143 struct i2c_msg msgs[] = {
144 {
145 .addr = DDC_ADDR,
146 .flags = 0,
147 .len = 1,
148 .buf = &offset,
149 }, {
150 .addr = DDC_ADDR,
151 .flags = I2C_M_RD,
152 .len = count,
153 .buf = buf,
154 }
155 };
156
157 r = i2c_transfer(adapter, msgs, 2);
158 if (r == 2)
159 return 0;
160
161 if (r != -EAGAIN)
162 break;
163 }
164
165 return r < 0 ? r : -EIO;
166 }
167
dvic_read_edid(struct omap_dss_device * dssdev,u8 * edid,int len)168 static int dvic_read_edid(struct omap_dss_device *dssdev,
169 u8 *edid, int len)
170 {
171 struct panel_drv_data *ddata = to_panel_data(dssdev);
172 int r, l, bytes_read;
173
174 if (!ddata->i2c_adapter)
175 return -ENODEV;
176
177 l = min(EDID_LENGTH, len);
178 r = dvic_ddc_read(ddata->i2c_adapter, edid, l, 0);
179 if (r)
180 return r;
181
182 bytes_read = l;
183
184 /* if there are extensions, read second block */
185 if (len > EDID_LENGTH && edid[0x7e] > 0) {
186 l = min(EDID_LENGTH, len - EDID_LENGTH);
187
188 r = dvic_ddc_read(ddata->i2c_adapter, edid + EDID_LENGTH,
189 l, EDID_LENGTH);
190 if (r)
191 return r;
192
193 bytes_read += l;
194 }
195
196 return bytes_read;
197 }
198
dvic_detect(struct omap_dss_device * dssdev)199 static bool dvic_detect(struct omap_dss_device *dssdev)
200 {
201 struct panel_drv_data *ddata = to_panel_data(dssdev);
202 unsigned char out;
203 int r;
204
205 if (!ddata->i2c_adapter)
206 return true;
207
208 r = dvic_ddc_read(ddata->i2c_adapter, &out, 1, 0);
209
210 return r == 0;
211 }
212
213 static struct omap_dss_driver dvic_driver = {
214 .connect = dvic_connect,
215 .disconnect = dvic_disconnect,
216
217 .enable = dvic_enable,
218 .disable = dvic_disable,
219
220 .set_timings = dvic_set_timings,
221 .get_timings = dvic_get_timings,
222 .check_timings = dvic_check_timings,
223
224 .get_resolution = omapdss_default_get_resolution,
225
226 .read_edid = dvic_read_edid,
227 .detect = dvic_detect,
228 };
229
dvic_probe_of(struct platform_device * pdev)230 static int dvic_probe_of(struct platform_device *pdev)
231 {
232 struct panel_drv_data *ddata = platform_get_drvdata(pdev);
233 struct device_node *node = pdev->dev.of_node;
234 struct omap_dss_device *in;
235 struct device_node *adapter_node;
236 struct i2c_adapter *adapter;
237
238 in = omapdss_of_find_source_for_first_ep(node);
239 if (IS_ERR(in)) {
240 dev_err(&pdev->dev, "failed to find video source\n");
241 return PTR_ERR(in);
242 }
243
244 ddata->in = in;
245
246 adapter_node = of_parse_phandle(node, "ddc-i2c-bus", 0);
247 if (adapter_node) {
248 adapter = of_get_i2c_adapter_by_node(adapter_node);
249 of_node_put(adapter_node);
250 if (adapter == NULL) {
251 dev_err(&pdev->dev, "failed to parse ddc-i2c-bus\n");
252 omap_dss_put_device(ddata->in);
253 return -EPROBE_DEFER;
254 }
255
256 ddata->i2c_adapter = adapter;
257 }
258
259 return 0;
260 }
261
dvic_probe(struct platform_device * pdev)262 static int dvic_probe(struct platform_device *pdev)
263 {
264 struct panel_drv_data *ddata;
265 struct omap_dss_device *dssdev;
266 int r;
267
268 if (!pdev->dev.of_node)
269 return -ENODEV;
270
271 ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
272 if (!ddata)
273 return -ENOMEM;
274
275 platform_set_drvdata(pdev, ddata);
276
277 r = dvic_probe_of(pdev);
278 if (r)
279 return r;
280
281 ddata->timings = dvic_default_timings;
282
283 dssdev = &ddata->dssdev;
284 dssdev->driver = &dvic_driver;
285 dssdev->dev = &pdev->dev;
286 dssdev->type = OMAP_DISPLAY_TYPE_DVI;
287 dssdev->owner = THIS_MODULE;
288 dssdev->panel.timings = dvic_default_timings;
289
290 r = omapdss_register_display(dssdev);
291 if (r) {
292 dev_err(&pdev->dev, "Failed to register panel\n");
293 goto err_reg;
294 }
295
296 return 0;
297
298 err_reg:
299 omap_dss_put_device(ddata->in);
300
301 i2c_put_adapter(ddata->i2c_adapter);
302
303 return r;
304 }
305
dvic_remove(struct platform_device * pdev)306 static void dvic_remove(struct platform_device *pdev)
307 {
308 struct panel_drv_data *ddata = platform_get_drvdata(pdev);
309 struct omap_dss_device *dssdev = &ddata->dssdev;
310 struct omap_dss_device *in = ddata->in;
311
312 omapdss_unregister_display(&ddata->dssdev);
313
314 dvic_disable(dssdev);
315 dvic_disconnect(dssdev);
316
317 omap_dss_put_device(in);
318
319 i2c_put_adapter(ddata->i2c_adapter);
320 }
321
322 static const struct of_device_id dvic_of_match[] = {
323 { .compatible = "omapdss,dvi-connector", },
324 {},
325 };
326
327 MODULE_DEVICE_TABLE(of, dvic_of_match);
328
329 static struct platform_driver dvi_connector_driver = {
330 .probe = dvic_probe,
331 .remove = dvic_remove,
332 .driver = {
333 .name = "connector-dvi",
334 .of_match_table = dvic_of_match,
335 },
336 };
337
338 module_platform_driver(dvi_connector_driver);
339
340 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
341 MODULE_DESCRIPTION("Generic DVI Connector driver");
342 MODULE_LICENSE("GPL");
343