1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Meson G12A USB2 PHY driver
4  *
5  * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
6  * Copyright (C) 2019 BayLibre, SAS
7  * Author: Neil Armstrong <narmstron@baylibre.com>
8  */
9 
10 #include <common.h>
11 #include <log.h>
12 #include <malloc.h>
13 #include <asm/io.h>
14 #include <bitfield.h>
15 #include <dm.h>
16 #include <errno.h>
17 #include <generic-phy.h>
18 #include <regmap.h>
19 #include <linux/delay.h>
20 #include <power/regulator.h>
21 #include <reset.h>
22 #include <clk.h>
23 
24 #include <linux/bitops.h>
25 #include <linux/compat.h>
26 
27 #define PHY_CTRL_R0						0x0
28 #define PHY_CTRL_R1						0x4
29 #define PHY_CTRL_R2						0x8
30 #define PHY_CTRL_R3						0xc
31 #define PHY_CTRL_R4						0x10
32 #define PHY_CTRL_R5						0x14
33 #define PHY_CTRL_R6						0x18
34 #define PHY_CTRL_R7						0x1c
35 #define PHY_CTRL_R8						0x20
36 #define PHY_CTRL_R9						0x24
37 #define PHY_CTRL_R10						0x28
38 #define PHY_CTRL_R11						0x2c
39 #define PHY_CTRL_R12						0x30
40 #define PHY_CTRL_R13						0x34
41 #define PHY_CTRL_R14						0x38
42 #define PHY_CTRL_R15						0x3c
43 #define PHY_CTRL_R16						0x40
44 #define PHY_CTRL_R17						0x44
45 #define PHY_CTRL_R18						0x48
46 #define PHY_CTRL_R19						0x4c
47 #define PHY_CTRL_R20						0x50
48 #define PHY_CTRL_R21						0x54
49 #define PHY_CTRL_R22						0x58
50 #define PHY_CTRL_R23						0x5c
51 
52 #define RESET_COMPLETE_TIME					1000
53 #define PLL_RESET_COMPLETE_TIME					100
54 
55 struct phy_meson_g12a_usb2_priv {
56 	struct regmap		*regmap;
57 #if CONFIG_IS_ENABLED(DM_REGULATOR)
58 	struct udevice		*phy_supply;
59 #endif
60 #if CONFIG_IS_ENABLED(CLK)
61 	struct clk		clk;
62 #endif
63 	struct reset_ctl	reset;
64 };
65 
66 
phy_meson_g12a_usb2_power_on(struct phy * phy)67 static int phy_meson_g12a_usb2_power_on(struct phy *phy)
68 {
69 #if CONFIG_IS_ENABLED(DM_REGULATOR)
70 	struct udevice *dev = phy->dev;
71 	struct phy_meson_g12a_usb2_priv *priv = dev_get_priv(dev);
72 
73 	if (priv->phy_supply) {
74 		int ret = regulator_set_enable(priv->phy_supply, true);
75 		if (ret)
76 			return ret;
77 	}
78 #endif
79 
80 	return 0;
81 }
82 
phy_meson_g12a_usb2_power_off(struct phy * phy)83 static int phy_meson_g12a_usb2_power_off(struct phy *phy)
84 {
85 #if CONFIG_IS_ENABLED(DM_REGULATOR)
86 	struct udevice *dev = phy->dev;
87 	struct phy_meson_g12a_usb2_priv *priv = dev_get_priv(dev);
88 
89 	if (priv->phy_supply) {
90 		int ret = regulator_set_enable(priv->phy_supply, false);
91 		if (ret) {
92 			pr_err("Error disabling PHY supply\n");
93 			return ret;
94 		}
95 	}
96 #endif
97 
98 	return 0;
99 }
100 
phy_meson_g12a_usb2_init(struct phy * phy)101 static int phy_meson_g12a_usb2_init(struct phy *phy)
102 {
103 	struct udevice *dev = phy->dev;
104 	struct phy_meson_g12a_usb2_priv *priv = dev_get_priv(dev);
105 	int ret;
106 
107 	ret = reset_assert(&priv->reset);
108 	udelay(1);
109 	ret |= reset_deassert(&priv->reset);
110 	if (ret)
111 		return ret;
112 
113 	udelay(RESET_COMPLETE_TIME);
114 
115 	/* usb2_otg_aca_en == 0 */
116 	regmap_update_bits(priv->regmap, PHY_CTRL_R21, BIT(2), 0);
117 
118 	/* PLL Setup : 24MHz * 20 / 1 = 480MHz */
119 	regmap_write(priv->regmap, PHY_CTRL_R16, 0x39400414);
120 	regmap_write(priv->regmap, PHY_CTRL_R17, 0x927e0000);
121 	regmap_write(priv->regmap, PHY_CTRL_R18, 0xac5f49e5);
122 
123 	udelay(PLL_RESET_COMPLETE_TIME);
124 
125 	/* UnReset PLL */
126 	regmap_write(priv->regmap, PHY_CTRL_R16, 0x19400414);
127 
128 	/* PHY Tuning */
129 	regmap_write(priv->regmap, PHY_CTRL_R20, 0xfe18);
130 	regmap_write(priv->regmap, PHY_CTRL_R4, 0x8000fff);
131 
132 	/* Tuning Disconnect Threshold */
133 	regmap_write(priv->regmap, PHY_CTRL_R3, 0x34);
134 
135 	/* Analog Settings */
136 	regmap_write(priv->regmap, PHY_CTRL_R14, 0);
137 	regmap_write(priv->regmap, PHY_CTRL_R13, 0x78000);
138 
139 	return 0;
140 }
141 
phy_meson_g12a_usb2_exit(struct phy * phy)142 static int phy_meson_g12a_usb2_exit(struct phy *phy)
143 {
144 	struct udevice *dev = phy->dev;
145 	struct phy_meson_g12a_usb2_priv *priv = dev_get_priv(dev);
146 	int ret;
147 
148 	ret = reset_assert(&priv->reset);
149 	if (ret)
150 		return ret;
151 
152 	return 0;
153 }
154 
155 struct phy_ops meson_g12a_usb2_phy_ops = {
156 	.init = phy_meson_g12a_usb2_init,
157 	.exit = phy_meson_g12a_usb2_exit,
158 	.power_on = phy_meson_g12a_usb2_power_on,
159 	.power_off = phy_meson_g12a_usb2_power_off,
160 };
161 
meson_g12a_usb2_phy_probe(struct udevice * dev)162 int meson_g12a_usb2_phy_probe(struct udevice *dev)
163 {
164 	struct phy_meson_g12a_usb2_priv *priv = dev_get_priv(dev);
165 	int ret;
166 
167 	ret = regmap_init_mem(dev_ofnode(dev), &priv->regmap);
168 	if (ret)
169 		return ret;
170 
171 	ret = reset_get_by_index(dev, 0, &priv->reset);
172 	if (ret == -ENOTSUPP)
173 		return 0;
174 	else if (ret)
175 		return ret;
176 
177 	ret = reset_deassert(&priv->reset);
178 	if (ret) {
179 		reset_release_all(&priv->reset, 1);
180 		return ret;
181 	}
182 
183 #if CONFIG_IS_ENABLED(CLK)
184 	ret = clk_get_by_index(dev, 0, &priv->clk);
185 	if (ret < 0)
186 		return ret;
187 
188 	ret = clk_enable(&priv->clk);
189 	if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
190 		pr_err("failed to enable PHY clock\n");
191 		clk_free(&priv->clk);
192 		return ret;
193 	}
194 #endif
195 
196 #if CONFIG_IS_ENABLED(DM_REGULATOR)
197 	ret = device_get_supply_regulator(dev, "phy-supply", &priv->phy_supply);
198 	if (ret && ret != -ENOENT) {
199 		pr_err("Failed to get PHY regulator\n");
200 		return ret;
201 	}
202 #endif
203 
204 	return 0;
205 }
206 
207 static const struct udevice_id meson_g12a_usb2_phy_ids[] = {
208 	{ .compatible = "amlogic,g12a-usb2-phy" },
209 	{ }
210 };
211 
212 U_BOOT_DRIVER(meson_g12a_usb2_phy) = {
213 	.name = "meson_g12a_usb2_phy",
214 	.id = UCLASS_PHY,
215 	.of_match = meson_g12a_usb2_phy_ids,
216 	.probe = meson_g12a_usb2_phy_probe,
217 	.ops = &meson_g12a_usb2_phy_ops,
218 	.priv_auto	= sizeof(struct phy_meson_g12a_usb2_priv),
219 };
220