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
28 struct keystone_usbphy {
29 struct usb_phy_generic usb_phy_gen;
30 void __iomem *phy_ctrl;
31 };
32
keystone_usbphy_readl(void __iomem * base,u32 offset)33 static inline u32 keystone_usbphy_readl(void __iomem *base, u32 offset)
34 {
35 return readl(base + offset);
36 }
37
keystone_usbphy_writel(void __iomem * base,u32 offset,u32 value)38 static inline void keystone_usbphy_writel(void __iomem *base,
39 u32 offset, u32 value)
40 {
41 writel(value, base + offset);
42 }
43
keystone_usbphy_init(struct usb_phy * phy)44 static 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
keystone_usbphy_shutdown(struct usb_phy * phy)55 static 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
keystone_usbphy_probe(struct platform_device * pdev)65 static 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
keystone_usbphy_remove(struct platform_device * pdev)91 static int 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 return 0;
98 }
99
100 static const struct of_device_id keystone_usbphy_ids[] = {
101 { .compatible = "ti,keystone-usbphy" },
102 { }
103 };
104 MODULE_DEVICE_TABLE(of, keystone_usbphy_ids);
105
106 static struct platform_driver keystone_usbphy_driver = {
107 .probe = keystone_usbphy_probe,
108 .remove = keystone_usbphy_remove,
109 .driver = {
110 .name = "keystone-usbphy",
111 .of_match_table = keystone_usbphy_ids,
112 },
113 };
114
115 module_platform_driver(keystone_usbphy_driver);
116
117 MODULE_ALIAS("platform:keystone-usbphy");
118 MODULE_AUTHOR("Texas Instruments Inc.");
119 MODULE_DESCRIPTION("Keystone USB phy driver");
120 MODULE_LICENSE("GPL v2");
121