1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
4 *
5 * Copyright (C) 2013 Linaro Limited
6 * Matt Porter <mporter@linaro.org>
7 */
8
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/err.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/phy/phy.h>
16 #include <linux/platform_device.h>
17
18 #define OTGCTL (0)
19 #define OTGCTL_OTGSTAT2 BIT(31)
20 #define OTGCTL_OTGSTAT1 BIT(30)
21 #define OTGCTL_PRST_N_SW BIT(11)
22 #define OTGCTL_HRESET_N BIT(10)
23 #define OTGCTL_UTMI_LINE_STATE1 BIT(9)
24 #define OTGCTL_UTMI_LINE_STATE0 BIT(8)
25
26 #define P1CTL (8)
27 #define P1CTL_SOFT_RESET BIT(1)
28 #define P1CTL_NON_DRIVING BIT(0)
29
30 struct bcm_kona_usb {
31 void __iomem *regs;
32 };
33
bcm_kona_usb_phy_power(struct bcm_kona_usb * phy,int on)34 static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
35 {
36 u32 val;
37
38 val = readl(phy->regs + OTGCTL);
39 if (on) {
40 /* Configure and power PHY */
41 val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
42 OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
43 val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
44 } else {
45 val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
46 }
47 writel(val, phy->regs + OTGCTL);
48 }
49
bcm_kona_usb_phy_init(struct phy * gphy)50 static int bcm_kona_usb_phy_init(struct phy *gphy)
51 {
52 struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
53 u32 val;
54
55 /* Soft reset PHY */
56 val = readl(phy->regs + P1CTL);
57 val &= ~P1CTL_NON_DRIVING;
58 val |= P1CTL_SOFT_RESET;
59 writel(val, phy->regs + P1CTL);
60 writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
61 /* Reset needs to be asserted for 2ms */
62 mdelay(2);
63 writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);
64
65 return 0;
66 }
67
bcm_kona_usb_phy_power_on(struct phy * gphy)68 static int bcm_kona_usb_phy_power_on(struct phy *gphy)
69 {
70 struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
71
72 bcm_kona_usb_phy_power(phy, 1);
73
74 return 0;
75 }
76
bcm_kona_usb_phy_power_off(struct phy * gphy)77 static int bcm_kona_usb_phy_power_off(struct phy *gphy)
78 {
79 struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
80
81 bcm_kona_usb_phy_power(phy, 0);
82
83 return 0;
84 }
85
86 static const struct phy_ops ops = {
87 .init = bcm_kona_usb_phy_init,
88 .power_on = bcm_kona_usb_phy_power_on,
89 .power_off = bcm_kona_usb_phy_power_off,
90 .owner = THIS_MODULE,
91 };
92
bcm_kona_usb2_probe(struct platform_device * pdev)93 static int bcm_kona_usb2_probe(struct platform_device *pdev)
94 {
95 struct device *dev = &pdev->dev;
96 struct bcm_kona_usb *phy;
97 struct phy *gphy;
98 struct phy_provider *phy_provider;
99
100 phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
101 if (!phy)
102 return -ENOMEM;
103
104 phy->regs = devm_platform_ioremap_resource(pdev, 0);
105 if (IS_ERR(phy->regs))
106 return PTR_ERR(phy->regs);
107
108 platform_set_drvdata(pdev, phy);
109
110 gphy = devm_phy_create(dev, NULL, &ops);
111 if (IS_ERR(gphy))
112 return PTR_ERR(gphy);
113
114 /* The Kona PHY supports an 8-bit wide UTMI interface */
115 phy_set_bus_width(gphy, 8);
116
117 phy_set_drvdata(gphy, phy);
118
119 phy_provider = devm_of_phy_provider_register(dev,
120 of_phy_simple_xlate);
121
122 return PTR_ERR_OR_ZERO(phy_provider);
123 }
124
125 static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
126 { .compatible = "brcm,kona-usb2-phy" },
127 { /* sentinel */ }
128 };
129
130 MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);
131
132 static struct platform_driver bcm_kona_usb2_driver = {
133 .probe = bcm_kona_usb2_probe,
134 .driver = {
135 .name = "bcm-kona-usb2",
136 .of_match_table = bcm_kona_usb2_dt_ids,
137 },
138 };
139
140 module_platform_driver(bcm_kona_usb2_driver);
141
142 MODULE_ALIAS("platform:bcm-kona-usb2");
143 MODULE_AUTHOR("Matt Porter <mporter@linaro.org>");
144 MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
145 MODULE_LICENSE("GPL v2");
146