1/*
2 * Allwinner sun9i USB phy driver
3 *
4 * Copyright (C) 2014-2015 Chen-Yu Tsai <wens@csie.org>
5 *
6 * Based on phy-sun4i-usb.c from
7 * Hans de Goede <hdegoede@redhat.com>
8 *
9 * and code from
10 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20 * GNU General Public License for more details.
21 */
22
23#include <linux/clk.h>
24#include <linux/err.h>
25#include <linux/io.h>
26#include <linux/module.h>
27#include <linux/phy/phy.h>
28#include <linux/usb/of.h>
29#include <linux/platform_device.h>
30#include <linux/reset.h>
31
32#define SUNXI_AHB_INCR16_BURST_EN	BIT(11)
33#define SUNXI_AHB_INCR8_BURST_EN	BIT(10)
34#define SUNXI_AHB_INCR4_BURST_EN	BIT(9)
35#define SUNXI_AHB_INCRX_ALIGN_EN	BIT(8)
36#define SUNXI_ULPI_BYPASS_EN		BIT(0)
37
38/* usb1 HSIC specific bits */
39#define SUNXI_EHCI_HS_FORCE		BIT(20)
40#define SUNXI_HSIC_CONNECT_DET		BIT(17)
41#define SUNXI_HSIC_CONNECT_INT		BIT(16)
42#define SUNXI_HSIC			BIT(1)
43
44struct sun9i_usb_phy {
45	struct phy *phy;
46	void __iomem *pmu;
47	struct reset_control *reset;
48	struct clk *clk;
49	struct clk *hsic_clk;
50	enum usb_phy_interface type;
51};
52
53static void sun9i_usb_phy_passby(struct sun9i_usb_phy *phy, int enable)
54{
55	u32 bits, reg_value;
56
57	bits = SUNXI_AHB_INCR16_BURST_EN | SUNXI_AHB_INCR8_BURST_EN |
58		SUNXI_AHB_INCR4_BURST_EN | SUNXI_AHB_INCRX_ALIGN_EN |
59		SUNXI_ULPI_BYPASS_EN;
60
61	if (phy->type == USBPHY_INTERFACE_MODE_HSIC)
62		bits |= SUNXI_HSIC | SUNXI_EHCI_HS_FORCE |
63			SUNXI_HSIC_CONNECT_DET | SUNXI_HSIC_CONNECT_INT;
64
65	reg_value = readl(phy->pmu);
66
67	if (enable)
68		reg_value |= bits;
69	else
70		reg_value &= ~bits;
71
72	writel(reg_value, phy->pmu);
73}
74
75static int sun9i_usb_phy_init(struct phy *_phy)
76{
77	struct sun9i_usb_phy *phy = phy_get_drvdata(_phy);
78	int ret;
79
80	ret = clk_prepare_enable(phy->clk);
81	if (ret)
82		goto err_clk;
83
84	ret = clk_prepare_enable(phy->hsic_clk);
85	if (ret)
86		goto err_hsic_clk;
87
88	ret = reset_control_deassert(phy->reset);
89	if (ret)
90		goto err_reset;
91
92	sun9i_usb_phy_passby(phy, 1);
93	return 0;
94
95err_reset:
96	clk_disable_unprepare(phy->hsic_clk);
97
98err_hsic_clk:
99	clk_disable_unprepare(phy->clk);
100
101err_clk:
102	return ret;
103}
104
105static int sun9i_usb_phy_exit(struct phy *_phy)
106{
107	struct sun9i_usb_phy *phy = phy_get_drvdata(_phy);
108
109	sun9i_usb_phy_passby(phy, 0);
110	reset_control_assert(phy->reset);
111	clk_disable_unprepare(phy->hsic_clk);
112	clk_disable_unprepare(phy->clk);
113
114	return 0;
115}
116
117static struct phy_ops sun9i_usb_phy_ops = {
118	.init		= sun9i_usb_phy_init,
119	.exit		= sun9i_usb_phy_exit,
120	.owner		= THIS_MODULE,
121};
122
123static int sun9i_usb_phy_probe(struct platform_device *pdev)
124{
125	struct sun9i_usb_phy *phy;
126	struct device *dev = &pdev->dev;
127	struct device_node *np = dev->of_node;
128	struct phy_provider *phy_provider;
129	struct resource *res;
130
131	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
132	if (!phy)
133		return -ENOMEM;
134
135	phy->type = of_usb_get_phy_mode(np);
136	if (phy->type == USBPHY_INTERFACE_MODE_HSIC) {
137		phy->clk = devm_clk_get(dev, "hsic_480M");
138		if (IS_ERR(phy->clk)) {
139			dev_err(dev, "failed to get hsic_480M clock\n");
140			return PTR_ERR(phy->clk);
141		}
142
143		phy->hsic_clk = devm_clk_get(dev, "hsic_12M");
144		if (IS_ERR(phy->clk)) {
145			dev_err(dev, "failed to get hsic_12M clock\n");
146			return PTR_ERR(phy->clk);
147		}
148
149		phy->reset = devm_reset_control_get(dev, "hsic");
150		if (IS_ERR(phy->reset)) {
151			dev_err(dev, "failed to get reset control\n");
152			return PTR_ERR(phy->reset);
153		}
154	} else {
155		phy->clk = devm_clk_get(dev, "phy");
156		if (IS_ERR(phy->clk)) {
157			dev_err(dev, "failed to get phy clock\n");
158			return PTR_ERR(phy->clk);
159		}
160
161		phy->reset = devm_reset_control_get(dev, "phy");
162		if (IS_ERR(phy->reset)) {
163			dev_err(dev, "failed to get reset control\n");
164			return PTR_ERR(phy->reset);
165		}
166	}
167
168	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
169	phy->pmu = devm_ioremap_resource(dev, res);
170	if (IS_ERR(phy->pmu))
171		return PTR_ERR(phy->pmu);
172
173	phy->phy = devm_phy_create(dev, NULL, &sun9i_usb_phy_ops);
174	if (IS_ERR(phy->phy)) {
175		dev_err(dev, "failed to create PHY\n");
176		return PTR_ERR(phy->phy);
177	}
178
179	phy_set_drvdata(phy->phy, phy);
180	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
181
182	return PTR_ERR_OR_ZERO(phy_provider);
183}
184
185static const struct of_device_id sun9i_usb_phy_of_match[] = {
186	{ .compatible = "allwinner,sun9i-a80-usb-phy" },
187	{ },
188};
189MODULE_DEVICE_TABLE(of, sun9i_usb_phy_of_match);
190
191static struct platform_driver sun9i_usb_phy_driver = {
192	.probe	= sun9i_usb_phy_probe,
193	.driver = {
194		.of_match_table	= sun9i_usb_phy_of_match,
195		.name  = "sun9i-usb-phy",
196	}
197};
198module_platform_driver(sun9i_usb_phy_driver);
199
200MODULE_DESCRIPTION("Allwinner sun9i USB phy driver");
201MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
202MODULE_LICENSE("GPL");
203