1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * phy-keystone - USB PHY, talking to dwc3 controller in Keystone.
4 *
5 * Copyright (C) 2013 Texas Instruments Incorporated - https://www.ti.com
6 *
7 * Author: WingMan Kwok <w-kwok2@ti.com>
8 */
9
10#include <linux/module.h>
11#include <linux/platform_device.h>
12#include <linux/usb/usb_phy_generic.h>
13#include <linux/io.h>
14#include <linux/of.h>
15
16#include "phy-generic.h"
17
18/* USB PHY control register offsets */
19#define USB_PHY_CTL_UTMI		0x0000
20#define USB_PHY_CTL_PIPE		0x0004
21#define USB_PHY_CTL_PARAM_1		0x0008
22#define USB_PHY_CTL_PARAM_2		0x000c
23#define USB_PHY_CTL_CLOCK		0x0010
24#define USB_PHY_CTL_PLL			0x0014
25
26#define PHY_REF_SSP_EN			BIT(29)
27
28struct keystone_usbphy {
29	struct usb_phy_generic	usb_phy_gen;
30	void __iomem			*phy_ctrl;
31};
32
33static inline u32 keystone_usbphy_readl(void __iomem *base, u32 offset)
34{
35	return readl(base + offset);
36}
37
38static inline void keystone_usbphy_writel(void __iomem *base,
39					  u32 offset, u32 value)
40{
41	writel(value, base + offset);
42}
43
44static int keystone_usbphy_init(struct usb_phy *phy)
45{
46	struct keystone_usbphy *k_phy = dev_get_drvdata(phy->dev);
47	u32 val;
48
49	val  = keystone_usbphy_readl(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK);
50	keystone_usbphy_writel(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK,
51				val | PHY_REF_SSP_EN);
52	return 0;
53}
54
55static void keystone_usbphy_shutdown(struct usb_phy *phy)
56{
57	struct keystone_usbphy *k_phy = dev_get_drvdata(phy->dev);
58	u32 val;
59
60	val  = keystone_usbphy_readl(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK);
61	keystone_usbphy_writel(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK,
62				val & ~PHY_REF_SSP_EN);
63}
64
65static int keystone_usbphy_probe(struct platform_device *pdev)
66{
67	struct device		*dev = &pdev->dev;
68	struct keystone_usbphy	*k_phy;
69	int ret;
70
71	k_phy = devm_kzalloc(dev, sizeof(*k_phy), GFP_KERNEL);
72	if (!k_phy)
73		return -ENOMEM;
74
75	k_phy->phy_ctrl = devm_platform_ioremap_resource(pdev, 0);
76	if (IS_ERR(k_phy->phy_ctrl))
77		return PTR_ERR(k_phy->phy_ctrl);
78
79	ret = usb_phy_gen_create_phy(dev, &k_phy->usb_phy_gen);
80	if (ret)
81		return ret;
82
83	k_phy->usb_phy_gen.phy.init = keystone_usbphy_init;
84	k_phy->usb_phy_gen.phy.shutdown = keystone_usbphy_shutdown;
85
86	platform_set_drvdata(pdev, k_phy);
87
88	return usb_add_phy_dev(&k_phy->usb_phy_gen.phy);
89}
90
91static void keystone_usbphy_remove(struct platform_device *pdev)
92{
93	struct keystone_usbphy *k_phy = platform_get_drvdata(pdev);
94
95	usb_remove_phy(&k_phy->usb_phy_gen.phy);
96}
97
98static const struct of_device_id keystone_usbphy_ids[] = {
99	{ .compatible = "ti,keystone-usbphy" },
100	{ }
101};
102MODULE_DEVICE_TABLE(of, keystone_usbphy_ids);
103
104static struct platform_driver keystone_usbphy_driver = {
105	.probe          = keystone_usbphy_probe,
106	.remove_new     = keystone_usbphy_remove,
107	.driver         = {
108		.name   = "keystone-usbphy",
109		.of_match_table = keystone_usbphy_ids,
110	},
111};
112
113module_platform_driver(keystone_usbphy_driver);
114
115MODULE_ALIAS("platform:keystone-usbphy");
116MODULE_AUTHOR("Texas Instruments Inc.");
117MODULE_DESCRIPTION("Keystone USB phy driver");
118MODULE_LICENSE("GPL v2");
119