xref: /openbmc/u-boot/drivers/phy/sti_usb_phy.c (revision a3b36c84)
1 /*
2  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
3  * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <asm/io.h>
10 #include <bitfield.h>
11 #include <dm.h>
12 #include <errno.h>
13 #include <fdtdec.h>
14 #include <generic-phy.h>
15 #include <libfdt.h>
16 #include <regmap.h>
17 #include <reset-uclass.h>
18 #include <syscon.h>
19 #include <wait_bit.h>
20 
21 #include <linux/bitops.h>
22 #include <linux/compat.h>
23 
24 DECLARE_GLOBAL_DATA_PTR;
25 
26 /* Default PHY_SEL and REFCLKSEL configuration */
27 #define STIH407_USB_PICOPHY_CTRL_PORT_CONF	0x6
28 
29 /* ports parameters overriding */
30 #define STIH407_USB_PICOPHY_PARAM_DEF		0x39a4dc
31 
32 #define PHYPARAM_REG	1
33 #define PHYCTRL_REG	2
34 #define PHYPARAM_NB	3
35 
36 struct sti_usb_phy {
37 	struct regmap *regmap;
38 	struct reset_ctl global_ctl;
39 	struct reset_ctl port_ctl;
40 	int param;
41 	int ctrl;
42 };
43 
44 static int sti_usb_phy_deassert(struct sti_usb_phy *phy)
45 {
46 	int ret;
47 
48 	ret = reset_deassert(&phy->global_ctl);
49 	if (ret < 0) {
50 		pr_err("PHY global deassert failed: %d", ret);
51 		return ret;
52 	}
53 
54 	ret = reset_deassert(&phy->port_ctl);
55 	if (ret < 0)
56 		pr_err("PHY port deassert failed: %d", ret);
57 
58 	return ret;
59 }
60 
61 static int sti_usb_phy_init(struct phy *usb_phy)
62 {
63 	struct udevice *dev = usb_phy->dev;
64 	struct sti_usb_phy *phy = dev_get_priv(dev);
65 	void __iomem *reg;
66 
67 	/* set ctrl picophy value */
68 	reg = (void __iomem *)phy->regmap->base + phy->ctrl;
69 	/* CTRL_PORT mask is 0x1f */
70 	clrsetbits_le32(reg, 0x1f, STIH407_USB_PICOPHY_CTRL_PORT_CONF);
71 
72 	/* set ports parameters overriding */
73 	reg = (void __iomem *)phy->regmap->base + phy->param;
74 	/* PARAM_DEF mask is 0xffffffff */
75 	clrsetbits_le32(reg, 0xffffffff, STIH407_USB_PICOPHY_PARAM_DEF);
76 
77 	return sti_usb_phy_deassert(phy);
78 }
79 
80 static int sti_usb_phy_exit(struct phy *usb_phy)
81 {
82 	struct udevice *dev = usb_phy->dev;
83 	struct sti_usb_phy *phy = dev_get_priv(dev);
84 	int ret;
85 
86 	ret = reset_assert(&phy->port_ctl);
87 	if (ret < 0) {
88 		pr_err("PHY port assert failed: %d", ret);
89 		return ret;
90 	}
91 
92 	ret = reset_assert(&phy->global_ctl);
93 	if (ret < 0)
94 		pr_err("PHY global assert failed: %d", ret);
95 
96 	return ret;
97 }
98 
99 struct phy_ops sti_usb_phy_ops = {
100 	.init = sti_usb_phy_init,
101 	.exit = sti_usb_phy_exit,
102 };
103 
104 int sti_usb_phy_probe(struct udevice *dev)
105 {
106 	struct sti_usb_phy *priv = dev_get_priv(dev);
107 	struct udevice *syscon;
108 	struct ofnode_phandle_args syscfg_phandle;
109 	u32 cells[PHYPARAM_NB];
110 	int ret, count;
111 
112 	/* get corresponding syscon phandle */
113 	ret = dev_read_phandle_with_args(dev, "st,syscfg", NULL, 0, 0,
114 					 &syscfg_phandle);
115 
116 	if (ret < 0) {
117 		pr_err("Can't get syscfg phandle: %d\n", ret);
118 		return ret;
119 	}
120 
121 	ret = uclass_get_device_by_ofnode(UCLASS_SYSCON, syscfg_phandle.node,
122 					  &syscon);
123 	if (ret) {
124 		pr_err("unable to find syscon device (%d)\n", ret);
125 		return ret;
126 	}
127 
128 	priv->regmap = syscon_get_regmap(syscon);
129 	if (!priv->regmap) {
130 		pr_err("unable to find regmap\n");
131 		return -ENODEV;
132 	}
133 
134 	/* get phy param offset */
135 	count = fdtdec_get_int_array_count(gd->fdt_blob, dev_of_offset(dev),
136 					   "st,syscfg", cells,
137 					   ARRAY_SIZE(cells));
138 
139 	if (count < 0) {
140 		pr_err("Bad PHY st,syscfg property %d\n", count);
141 		return -EINVAL;
142 	}
143 
144 	if (count > PHYPARAM_NB) {
145 		pr_err("Unsupported PHY param count %d\n", count);
146 		return -EINVAL;
147 	}
148 
149 	priv->param = cells[PHYPARAM_REG];
150 	priv->ctrl = cells[PHYCTRL_REG];
151 
152 	/* get global reset control */
153 	ret = reset_get_by_name(dev, "global", &priv->global_ctl);
154 	if (ret) {
155 		pr_err("can't get global reset for %s (%d)", dev->name, ret);
156 		return ret;
157 	}
158 
159 	/* get port reset control */
160 	ret = reset_get_by_name(dev, "port", &priv->port_ctl);
161 	if (ret) {
162 		pr_err("can't get port reset for %s (%d)", dev->name, ret);
163 		return ret;
164 	}
165 
166 	return 0;
167 }
168 
169 static const struct udevice_id sti_usb_phy_ids[] = {
170 	{ .compatible = "st,stih407-usb2-phy" },
171 	{ }
172 };
173 
174 U_BOOT_DRIVER(sti_usb_phy) = {
175 	.name = "sti_usb_phy",
176 	.id = UCLASS_PHY,
177 	.of_match = sti_usb_phy_ids,
178 	.probe = sti_usb_phy_probe,
179 	.ops = &sti_usb_phy_ops,
180 	.priv_auto_alloc_size = sizeof(struct sti_usb_phy),
181 };
182