1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
4  * Written by Jean-Jacques Hiblot  <jjhiblot@ti.com>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <log.h>
10 #include <dm/device.h>
11 #include <generic-phy.h>
12 #include <asm/io.h>
13 #include <asm/arch/psc_defs.h>
14 #include <linux/bitops.h>
15 #include <linux/delay.h>
16 
17 /* USB PHY control register offsets */
18 #define USB_PHY_CTL_UTMI		0x0000
19 #define USB_PHY_CTL_PIPE		0x0004
20 #define USB_PHY_CTL_PARAM_1		0x0008
21 #define USB_PHY_CTL_PARAM_2		0x000c
22 #define USB_PHY_CTL_CLOCK		0x0010
23 #define USB_PHY_CTL_PLL			0x0014
24 
25 #define PHY_OTG_VBUSVLDECTSEL		BIT(16)
26 #define PHY_REF_SSP_EN			BIT(29)
27 
28 struct keystone_usb_phy {
29 	u32 psc_domain;
30 	void __iomem *reg;
31 };
32 
keystone_usb_init(struct phy * phy)33 static int keystone_usb_init(struct phy *phy)
34 {
35 	u32 val;
36 	int rc;
37 	struct udevice *dev = phy->dev;
38 	struct keystone_usb_phy *keystone = dev_get_priv(dev);
39 
40 	/* Release USB from reset */
41 	rc = psc_enable_module(keystone->psc_domain);
42 	if (rc) {
43 		debug("Cannot enable USB module");
44 		return -rc;
45 	}
46 	mdelay(10);
47 
48 	/*
49 	 * VBUSVLDEXTSEL has a default value of 1 in BootCfg but shouldn't.
50 	 * It should always be cleared because our USB PHY has an onchip VBUS
51 	 * analog comparator.
52 	 */
53 	val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
54 	/* quit selecting the vbusvldextsel by default! */
55 	val &= ~PHY_OTG_VBUSVLDECTSEL;
56 	writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
57 
58 	return 0;
59 }
60 
keystone_usb_power_on(struct phy * phy)61 static int keystone_usb_power_on(struct phy *phy)
62 {
63 	u32 val;
64 	struct udevice *dev = phy->dev;
65 	struct keystone_usb_phy *keystone = dev_get_priv(dev);
66 
67 	val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
68 	val |= PHY_REF_SSP_EN;
69 	writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
70 
71 	return 0;
72 }
73 
keystone_usb_power_off(struct phy * phy)74 static int keystone_usb_power_off(struct phy *phy)
75 {
76 	u32 val;
77 	struct udevice *dev = phy->dev;
78 	struct keystone_usb_phy *keystone = dev_get_priv(dev);
79 
80 	val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
81 	val &= ~PHY_REF_SSP_EN;
82 	writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
83 
84 	return 0;
85 }
86 
keystone_usb_exit(struct phy * phy)87 static int keystone_usb_exit(struct phy *phy)
88 {
89 	struct udevice *dev = phy->dev;
90 	struct keystone_usb_phy *keystone = dev_get_priv(dev);
91 
92 	if (psc_disable_module(keystone->psc_domain))
93 		debug("failed to disable USB module!\n");
94 
95 	return 0;
96 }
97 
keystone_usb_phy_probe(struct udevice * dev)98 static int keystone_usb_phy_probe(struct udevice *dev)
99 {
100 	int rc;
101 	struct keystone_usb_phy *keystone = dev_get_priv(dev);
102 
103 	rc = dev_read_u32(dev, "psc-domain", &keystone->psc_domain);
104 	if (rc)
105 		return rc;
106 
107 	keystone->reg = dev_remap_addr_index(dev, 0);
108 	if (!keystone->reg) {
109 		pr_err("unable to remap usb phy\n");
110 		return -EINVAL;
111 	}
112 	return 0;
113 }
114 
115 static const struct udevice_id keystone_usb_phy_ids[] = {
116 	{ .compatible = "ti,keystone-usbphy" },
117 	{ }
118 };
119 
120 static struct phy_ops keystone_usb_phy_ops = {
121 	.init = keystone_usb_init,
122 	.power_on = keystone_usb_power_on,
123 	.power_off = keystone_usb_power_off,
124 	.exit = keystone_usb_exit,
125 };
126 
127 U_BOOT_DRIVER(keystone_usb_phy) = {
128 	.name	= "keystone_usb_phy",
129 	.id	= UCLASS_PHY,
130 	.of_match = keystone_usb_phy_ids,
131 	.ops = &keystone_usb_phy_ops,
132 	.probe = keystone_usb_phy_probe,
133 	.priv_auto	= sizeof(struct keystone_usb_phy),
134 };
135