1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2007 Intel Corporation
4 *
5 * Authers: Jesse Barnes <jesse.barnes@intel.com>
6 */
7
8#include <linux/i2c.h>
9
10#include <drm/drm_edid.h>
11
12#include "psb_intel_drv.h"
13
14/**
15 * psb_intel_ddc_probe
16 * @adapter:   Associated I2C adaptor
17 */
18bool psb_intel_ddc_probe(struct i2c_adapter *adapter)
19{
20	u8 out_buf[] = { 0x0, 0x0 };
21	u8 buf[2];
22	int ret;
23	struct i2c_msg msgs[] = {
24		{
25		 .addr = 0x50,
26		 .flags = 0,
27		 .len = 1,
28		 .buf = out_buf,
29		 },
30		{
31		 .addr = 0x50,
32		 .flags = I2C_M_RD,
33		 .len = 1,
34		 .buf = buf,
35		 }
36	};
37
38	ret = i2c_transfer(adapter, msgs, 2);
39	if (ret == 2)
40		return true;
41
42	return false;
43}
44
45/**
46 * psb_intel_ddc_get_modes - get modelist from monitor
47 * @connector: DRM connector device to use
48 * @adapter:   Associated I2C adaptor
49 *
50 * Fetch the EDID information from @connector using the DDC bus.
51 */
52int psb_intel_ddc_get_modes(struct drm_connector *connector,
53			    struct i2c_adapter *adapter)
54{
55	struct edid *edid;
56	int ret = 0;
57
58	edid = drm_get_edid(connector, adapter);
59	if (edid) {
60		drm_connector_update_edid_property(connector, edid);
61		ret = drm_add_edid_modes(connector, edid);
62		kfree(edid);
63	}
64	return ret;
65}
66