1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * StarFive JH7110 USB 2.0 PHY driver
  4 *
  5 * Copyright (C) 2023 StarFive Technology Co., Ltd.
  6 * Author: Minda Chen <minda.chen@starfivetech.com>
  7 */
  8
  9#include <linux/bits.h>
 10#include <linux/clk.h>
 11#include <linux/err.h>
 12#include <linux/io.h>
 13#include <linux/module.h>
 14#include <linux/phy/phy.h>
 15#include <linux/platform_device.h>
 16#include <linux/usb/of.h>
 17
 18#define USB_125M_CLK_RATE		125000000
 19#define USB_LS_KEEPALIVE_OFF		0x4
 20#define USB_LS_KEEPALIVE_ENABLE		BIT(4)
 21
 22struct jh7110_usb2_phy {
 23	struct phy *phy;
 24	void __iomem *regs;
 25	struct clk *usb_125m_clk;
 26	struct clk *app_125m;
 27	enum phy_mode mode;
 28};
 29
 30static void usb2_set_ls_keepalive(struct jh7110_usb2_phy *phy, bool set)
 31{
 32	unsigned int val;
 33
 34	/* Host mode enable the LS speed keep-alive signal */
 35	val = readl(phy->regs + USB_LS_KEEPALIVE_OFF);
 36	if (set)
 37		val |= USB_LS_KEEPALIVE_ENABLE;
 38	else
 39		val &= ~USB_LS_KEEPALIVE_ENABLE;
 40
 41	writel(val, phy->regs + USB_LS_KEEPALIVE_OFF);
 42}
 43
 44static int usb2_phy_set_mode(struct phy *_phy,
 45			     enum phy_mode mode, int submode)
 46{
 47	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
 48
 49	switch (mode) {
 50	case PHY_MODE_USB_HOST:
 51	case PHY_MODE_USB_DEVICE:
 52	case PHY_MODE_USB_OTG:
 53		break;
 54	default:
 55		return -EINVAL;
 56	}
 57
 58	if (mode != phy->mode) {
 59		dev_dbg(&_phy->dev, "Changing phy to %d\n", mode);
 60		phy->mode = mode;
 61		usb2_set_ls_keepalive(phy, (mode != PHY_MODE_USB_DEVICE));
 62	}
 63
 64	return 0;
 65}
 66
 67static int jh7110_usb2_phy_init(struct phy *_phy)
 68{
 69	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
 70	int ret;
 71
 72	ret = clk_set_rate(phy->usb_125m_clk, USB_125M_CLK_RATE);
 73	if (ret)
 74		return ret;
 75
 76	ret = clk_prepare_enable(phy->app_125m);
 77	if (ret)
 78		return ret;
 79
 80	return 0;
 81}
 82
 83static int jh7110_usb2_phy_exit(struct phy *_phy)
 84{
 85	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
 86
 87	clk_disable_unprepare(phy->app_125m);
 88
 89	return 0;
 90}
 91
 92static const struct phy_ops jh7110_usb2_phy_ops = {
 93	.init		= jh7110_usb2_phy_init,
 94	.exit		= jh7110_usb2_phy_exit,
 95	.set_mode	= usb2_phy_set_mode,
 96	.owner		= THIS_MODULE,
 97};
 98
 99static int jh7110_usb_phy_probe(struct platform_device *pdev)
100{
101	struct jh7110_usb2_phy *phy;
102	struct device *dev = &pdev->dev;
103	struct phy_provider *phy_provider;
104
105	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
106	if (!phy)
107		return -ENOMEM;
108
109	phy->usb_125m_clk = devm_clk_get(dev, "125m");
110	if (IS_ERR(phy->usb_125m_clk))
111		return dev_err_probe(dev, PTR_ERR(phy->usb_125m_clk),
112			"Failed to get 125m clock\n");
113
114	phy->app_125m = devm_clk_get(dev, "app_125m");
115	if (IS_ERR(phy->app_125m))
116		return dev_err_probe(dev, PTR_ERR(phy->app_125m),
117			"Failed to get app 125m clock\n");
118
119	phy->regs = devm_platform_ioremap_resource(pdev, 0);
120	if (IS_ERR(phy->regs))
121		return dev_err_probe(dev, PTR_ERR(phy->regs),
122			"Failed to map phy base\n");
123
124	phy->phy = devm_phy_create(dev, NULL, &jh7110_usb2_phy_ops);
125	if (IS_ERR(phy->phy))
126		return dev_err_probe(dev, PTR_ERR(phy->phy),
127			"Failed to create phy\n");
128
129	phy_set_drvdata(phy->phy, phy);
130	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
131
132	return PTR_ERR_OR_ZERO(phy_provider);
133}
134
135static const struct of_device_id jh7110_usb_phy_of_match[] = {
136	{ .compatible = "starfive,jh7110-usb-phy" },
137	{ /* sentinel */ },
138};
139MODULE_DEVICE_TABLE(of, jh7110_usb_phy_of_match);
140
141static struct platform_driver jh7110_usb_phy_driver = {
142	.probe	= jh7110_usb_phy_probe,
143	.driver = {
144		.of_match_table	= jh7110_usb_phy_of_match,
145		.name  = "jh7110-usb-phy",
146	}
147};
148module_platform_driver(jh7110_usb_phy_driver);
149
150MODULE_DESCRIPTION("StarFive JH7110 USB 2.0 PHY driver");
151MODULE_AUTHOR("Minda Chen <minda.chen@starfivetech.com>");
152MODULE_LICENSE("GPL");