xref: /linux/drivers/gpu/drm/gma500/psb_intel_modes.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 <linux/fb.h>
22 #include <drm/drmP.h>
23 #include "psb_intel_drv.h"
24 
25 /**
26  * psb_intel_ddc_probe
27  *
28  */
29 bool psb_intel_ddc_probe(struct i2c_adapter *adapter)
30 {
31 	u8 out_buf[] = { 0x0, 0x0 };
32 	u8 buf[2];
33 	int ret;
34 	struct i2c_msg msgs[] = {
35 		{
36 		 .addr = 0x50,
37 		 .flags = 0,
38 		 .len = 1,
39 		 .buf = out_buf,
40 		 },
41 		{
42 		 .addr = 0x50,
43 		 .flags = I2C_M_RD,
44 		 .len = 1,
45 		 .buf = buf,
46 		 }
47 	};
48 
49 	ret = i2c_transfer(adapter, msgs, 2);
50 	if (ret == 2)
51 		return true;
52 
53 	return false;
54 }
55 
56 /**
57  * psb_intel_ddc_get_modes - get modelist from monitor
58  * @connector: DRM connector device to use
59  *
60  * Fetch the EDID information from @connector using the DDC bus.
61  */
62 int psb_intel_ddc_get_modes(struct drm_connector *connector,
63 			    struct i2c_adapter *adapter)
64 {
65 	struct edid *edid;
66 	int ret = 0;
67 
68 	edid = drm_get_edid(connector, adapter);
69 	if (edid) {
70 		drm_mode_connector_update_edid_property(connector, edid);
71 		ret = drm_add_edid_modes(connector, edid);
72 		kfree(edid);
73 	}
74 	return ret;
75 }
76