1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Amlogic AXG MIPI + PCIE analog PHY driver
4  *
5  * Copyright (C) 2019 Remi Pommarel <repk@triplefau.lt>
6  */
7 #include <linux/module.h>
8 #include <linux/phy/phy.h>
9 #include <linux/regmap.h>
10 #include <linux/platform_device.h>
11 #include <dt-bindings/phy/phy.h>
12 
13 #define HHI_MIPI_CNTL0 0x00
14 #define		HHI_MIPI_CNTL0_COMMON_BLOCK	GENMASK(31, 28)
15 #define		HHI_MIPI_CNTL0_ENABLE		BIT(29)
16 #define		HHI_MIPI_CNTL0_BANDGAP		BIT(26)
17 #define		HHI_MIPI_CNTL0_DECODE_TO_RTERM	GENMASK(15, 12)
18 #define		HHI_MIPI_CNTL0_OUTPUT_EN	BIT(3)
19 
20 #define HHI_MIPI_CNTL1 0x01
21 #define		HHI_MIPI_CNTL1_CH0_CML_PDR_EN	BIT(12)
22 #define		HHI_MIPI_CNTL1_LP_ABILITY	GENMASK(5, 4)
23 #define		HHI_MIPI_CNTL1_LP_RESISTER	BIT(3)
24 #define		HHI_MIPI_CNTL1_INPUT_SETTING	BIT(2)
25 #define		HHI_MIPI_CNTL1_INPUT_SEL	BIT(1)
26 #define		HHI_MIPI_CNTL1_PRBS7_EN		BIT(0)
27 
28 #define HHI_MIPI_CNTL2 0x02
29 #define		HHI_MIPI_CNTL2_CH_PU		GENMASK(31, 25)
30 #define		HHI_MIPI_CNTL2_CH_CTL		GENMASK(24, 19)
31 #define		HHI_MIPI_CNTL2_CH0_DIGDR_EN	BIT(18)
32 #define		HHI_MIPI_CNTL2_CH_DIGDR_EN	BIT(17)
33 #define		HHI_MIPI_CNTL2_LPULPS_EN	BIT(16)
34 #define		HHI_MIPI_CNTL2_CH_EN(n)		BIT(15 - (n))
35 #define		HHI_MIPI_CNTL2_CH0_LP_CTL	GENMASK(10, 1)
36 
37 struct phy_axg_mipi_pcie_analog_priv {
38 	struct phy *phy;
39 	unsigned int mode;
40 	struct regmap *regmap;
41 };
42 
43 static const struct regmap_config phy_axg_mipi_pcie_analog_regmap_conf = {
44 	.reg_bits = 8,
45 	.val_bits = 32,
46 	.reg_stride = 4,
47 	.max_register = HHI_MIPI_CNTL2,
48 };
49 
50 static int phy_axg_mipi_pcie_analog_power_on(struct phy *phy)
51 {
52 	struct phy_axg_mipi_pcie_analog_priv *priv = phy_get_drvdata(phy);
53 
54 	/* MIPI not supported yet */
55 	if (priv->mode != PHY_TYPE_PCIE)
56 		return -EINVAL;
57 
58 	regmap_update_bits(priv->regmap, HHI_MIPI_CNTL0,
59 			   HHI_MIPI_CNTL0_BANDGAP, HHI_MIPI_CNTL0_BANDGAP);
60 
61 	regmap_update_bits(priv->regmap, HHI_MIPI_CNTL0,
62 			   HHI_MIPI_CNTL0_ENABLE, HHI_MIPI_CNTL0_ENABLE);
63 	return 0;
64 }
65 
66 static int phy_axg_mipi_pcie_analog_power_off(struct phy *phy)
67 {
68 	struct phy_axg_mipi_pcie_analog_priv *priv = phy_get_drvdata(phy);
69 
70 	/* MIPI not supported yet */
71 	if (priv->mode != PHY_TYPE_PCIE)
72 		return -EINVAL;
73 
74 	regmap_update_bits(priv->regmap, HHI_MIPI_CNTL0,
75 			   HHI_MIPI_CNTL0_BANDGAP, 0);
76 	regmap_update_bits(priv->regmap, HHI_MIPI_CNTL0,
77 			   HHI_MIPI_CNTL0_ENABLE, 0);
78 	return 0;
79 }
80 
81 static int phy_axg_mipi_pcie_analog_init(struct phy *phy)
82 {
83 	return 0;
84 }
85 
86 static int phy_axg_mipi_pcie_analog_exit(struct phy *phy)
87 {
88 	return 0;
89 }
90 
91 static const struct phy_ops phy_axg_mipi_pcie_analog_ops = {
92 	.init = phy_axg_mipi_pcie_analog_init,
93 	.exit = phy_axg_mipi_pcie_analog_exit,
94 	.power_on = phy_axg_mipi_pcie_analog_power_on,
95 	.power_off = phy_axg_mipi_pcie_analog_power_off,
96 	.owner = THIS_MODULE,
97 };
98 
99 static struct phy *phy_axg_mipi_pcie_analog_xlate(struct device *dev,
100 						  struct of_phandle_args *args)
101 {
102 	struct phy_axg_mipi_pcie_analog_priv *priv = dev_get_drvdata(dev);
103 	unsigned int mode;
104 
105 	if (args->args_count != 1) {
106 		dev_err(dev, "invalid number of arguments\n");
107 		return ERR_PTR(-EINVAL);
108 	}
109 
110 	mode = args->args[0];
111 
112 	/* MIPI mode is not supported yet */
113 	if (mode != PHY_TYPE_PCIE) {
114 		dev_err(dev, "invalid phy mode select argument\n");
115 		return ERR_PTR(-EINVAL);
116 	}
117 
118 	priv->mode = mode;
119 	return priv->phy;
120 }
121 
122 static int phy_axg_mipi_pcie_analog_probe(struct platform_device *pdev)
123 {
124 	struct phy_provider *phy;
125 	struct device *dev = &pdev->dev;
126 	struct phy_axg_mipi_pcie_analog_priv *priv;
127 	struct device_node *np = dev->of_node;
128 	struct regmap *map;
129 	struct resource *res;
130 	void __iomem *base;
131 	int ret;
132 
133 	priv = devm_kmalloc(dev, sizeof(*priv), GFP_KERNEL);
134 	if (!priv)
135 		return -ENOMEM;
136 
137 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
138 	base = devm_ioremap_resource(dev, res);
139 	if (IS_ERR(base)) {
140 		dev_err(dev, "failed to get regmap base\n");
141 		return PTR_ERR(base);
142 	}
143 
144 	map = devm_regmap_init_mmio(dev, base,
145 				    &phy_axg_mipi_pcie_analog_regmap_conf);
146 	if (IS_ERR(map)) {
147 		dev_err(dev, "failed to get HHI regmap\n");
148 		return PTR_ERR(map);
149 	}
150 	priv->regmap = map;
151 
152 	priv->phy = devm_phy_create(dev, np, &phy_axg_mipi_pcie_analog_ops);
153 	if (IS_ERR(priv->phy)) {
154 		ret = PTR_ERR(priv->phy);
155 		if (ret != -EPROBE_DEFER)
156 			dev_err(dev, "failed to create PHY\n");
157 		return ret;
158 	}
159 
160 	phy_set_drvdata(priv->phy, priv);
161 	dev_set_drvdata(dev, priv);
162 
163 	phy = devm_of_phy_provider_register(dev,
164 					    phy_axg_mipi_pcie_analog_xlate);
165 
166 	return PTR_ERR_OR_ZERO(phy);
167 }
168 
169 static const struct of_device_id phy_axg_mipi_pcie_analog_of_match[] = {
170 	{
171 		.compatible = "amlogic,axg-mipi-pcie-analog-phy",
172 	},
173 	{ },
174 };
175 MODULE_DEVICE_TABLE(of, phy_axg_mipi_pcie_analog_of_match);
176 
177 static struct platform_driver phy_axg_mipi_pcie_analog_driver = {
178 	.probe = phy_axg_mipi_pcie_analog_probe,
179 	.driver = {
180 		.name = "phy-axg-mipi-pcie-analog",
181 		.of_match_table = phy_axg_mipi_pcie_analog_of_match,
182 	},
183 };
184 module_platform_driver(phy_axg_mipi_pcie_analog_driver);
185 
186 MODULE_AUTHOR("Remi Pommarel <repk@triplefau.lt>");
187 MODULE_DESCRIPTION("Amlogic AXG MIPI + PCIE analog PHY driver");
188 MODULE_LICENSE("GPL v2");
189