1 /*
2  * Copyright (c) 2007 Intel Corporation
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16  *
17  * Authers: Jesse Barnes <jesse.barnes@intel.com>
18  */
19 
20 #include <linux/i2c.h>
21 #include <drm/drmP.h>
22 #include "psb_intel_drv.h"
23 
24 /**
25  * psb_intel_ddc_probe
26  *
27  */
28 bool psb_intel_ddc_probe(struct i2c_adapter *adapter)
29 {
30 	u8 out_buf[] = { 0x0, 0x0 };
31 	u8 buf[2];
32 	int ret;
33 	struct i2c_msg msgs[] = {
34 		{
35 		 .addr = 0x50,
36 		 .flags = 0,
37 		 .len = 1,
38 		 .buf = out_buf,
39 		 },
40 		{
41 		 .addr = 0x50,
42 		 .flags = I2C_M_RD,
43 		 .len = 1,
44 		 .buf = buf,
45 		 }
46 	};
47 
48 	ret = i2c_transfer(adapter, msgs, 2);
49 	if (ret == 2)
50 		return true;
51 
52 	return false;
53 }
54 
55 /**
56  * psb_intel_ddc_get_modes - get modelist from monitor
57  * @connector: DRM connector device to use
58  *
59  * Fetch the EDID information from @connector using the DDC bus.
60  */
61 int psb_intel_ddc_get_modes(struct drm_connector *connector,
62 			    struct i2c_adapter *adapter)
63 {
64 	struct edid *edid;
65 	int ret = 0;
66 
67 	edid = drm_get_edid(connector, adapter);
68 	if (edid) {
69 		drm_connector_update_edid_property(connector, edid);
70 		ret = drm_add_edid_modes(connector, edid);
71 		kfree(edid);
72 	}
73 	return ret;
74 }
75