1 /*
2 * Samsung EXYNOS SoC series Display Port PHY driver
3 *
4 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
5 * Author: Jingoo Han <jg1.han@samsung.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/err.h>
13 #include <linux/io.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/mfd/syscon/exynos5-pmu.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 #include <linux/phy/phy.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23
24 struct exynos_dp_video_phy_drvdata {
25 u32 phy_ctrl_offset;
26 };
27
28 struct exynos_dp_video_phy {
29 struct regmap *regs;
30 const struct exynos_dp_video_phy_drvdata *drvdata;
31 };
32
exynos_dp_video_phy_pwr_isol(struct exynos_dp_video_phy * state,unsigned int on)33 static void exynos_dp_video_phy_pwr_isol(struct exynos_dp_video_phy *state,
34 unsigned int on)
35 {
36 unsigned int val;
37
38 if (IS_ERR(state->regs))
39 return;
40
41 val = on ? 0 : EXYNOS5_PHY_ENABLE;
42
43 regmap_update_bits(state->regs, state->drvdata->phy_ctrl_offset,
44 EXYNOS5_PHY_ENABLE, val);
45 }
46
exynos_dp_video_phy_power_on(struct phy * phy)47 static int exynos_dp_video_phy_power_on(struct phy *phy)
48 {
49 struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
50
51 /* Disable power isolation on DP-PHY */
52 exynos_dp_video_phy_pwr_isol(state, 0);
53
54 return 0;
55 }
56
exynos_dp_video_phy_power_off(struct phy * phy)57 static int exynos_dp_video_phy_power_off(struct phy *phy)
58 {
59 struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
60
61 /* Enable power isolation on DP-PHY */
62 exynos_dp_video_phy_pwr_isol(state, 1);
63
64 return 0;
65 }
66
67 static struct phy_ops exynos_dp_video_phy_ops = {
68 .power_on = exynos_dp_video_phy_power_on,
69 .power_off = exynos_dp_video_phy_power_off,
70 .owner = THIS_MODULE,
71 };
72
73 static const struct exynos_dp_video_phy_drvdata exynos5250_dp_video_phy = {
74 .phy_ctrl_offset = EXYNOS5_DPTX_PHY_CONTROL,
75 };
76
77 static const struct exynos_dp_video_phy_drvdata exynos5420_dp_video_phy = {
78 .phy_ctrl_offset = EXYNOS5420_DPTX_PHY_CONTROL,
79 };
80
81 static const struct of_device_id exynos_dp_video_phy_of_match[] = {
82 {
83 .compatible = "samsung,exynos5250-dp-video-phy",
84 .data = &exynos5250_dp_video_phy,
85 }, {
86 .compatible = "samsung,exynos5420-dp-video-phy",
87 .data = &exynos5420_dp_video_phy,
88 },
89 { },
90 };
91 MODULE_DEVICE_TABLE(of, exynos_dp_video_phy_of_match);
92
exynos_dp_video_phy_probe(struct platform_device * pdev)93 static int exynos_dp_video_phy_probe(struct platform_device *pdev)
94 {
95 struct exynos_dp_video_phy *state;
96 struct device *dev = &pdev->dev;
97 const struct of_device_id *match;
98 struct phy_provider *phy_provider;
99 struct phy *phy;
100
101 state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
102 if (!state)
103 return -ENOMEM;
104
105 state->regs = syscon_regmap_lookup_by_phandle(dev->of_node,
106 "samsung,pmu-syscon");
107 if (IS_ERR(state->regs)) {
108 dev_err(dev, "Failed to lookup PMU regmap\n");
109 return PTR_ERR(state->regs);
110 }
111
112 match = of_match_node(exynos_dp_video_phy_of_match, dev->of_node);
113 state->drvdata = match->data;
114
115 phy = devm_phy_create(dev, NULL, &exynos_dp_video_phy_ops, NULL);
116 if (IS_ERR(phy)) {
117 dev_err(dev, "failed to create Display Port PHY\n");
118 return PTR_ERR(phy);
119 }
120 phy_set_drvdata(phy, state);
121
122 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
123
124 return PTR_ERR_OR_ZERO(phy_provider);
125 }
126
127 static struct platform_driver exynos_dp_video_phy_driver = {
128 .probe = exynos_dp_video_phy_probe,
129 .driver = {
130 .name = "exynos-dp-video-phy",
131 .of_match_table = exynos_dp_video_phy_of_match,
132 }
133 };
134 module_platform_driver(exynos_dp_video_phy_driver);
135
136 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
137 MODULE_DESCRIPTION("Samsung EXYNOS SoC DP PHY driver");
138 MODULE_LICENSE("GPL v2");
139