1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2014 STMicroelectronics |
4 | * |
5 | * STMicroelectronics Generic PHY driver for STiH407 USB2. |
6 | * |
7 | * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com> |
8 | */ |
9 | #include <linux/platform_device.h> |
10 | #include <linux/io.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/module.h> |
13 | #include <linux/of.h> |
14 | #include <linux/of_platform.h> |
15 | #include <linux/clk.h> |
16 | #include <linux/regmap.h> |
17 | #include <linux/reset.h> |
18 | #include <linux/mfd/syscon.h> |
19 | #include <linux/phy/phy.h> |
20 | |
21 | #define PHYPARAM_REG 1 |
22 | #define PHYCTRL_REG 2 |
23 | |
24 | /* Default PHY_SEL and REFCLKSEL configuration */ |
25 | #define STIH407_USB_PICOPHY_CTRL_PORT_CONF 0x6 |
26 | #define STIH407_USB_PICOPHY_CTRL_PORT_MASK 0x1f |
27 | |
28 | /* ports parameters overriding */ |
29 | #define STIH407_USB_PICOPHY_PARAM_DEF 0x39a4dc |
30 | #define STIH407_USB_PICOPHY_PARAM_MASK 0xffffffff |
31 | |
32 | struct stih407_usb2_picophy { |
33 | struct phy *phy; |
34 | struct regmap *regmap; |
35 | struct device *dev; |
36 | struct reset_control *rstc; |
37 | struct reset_control *rstport; |
38 | int ctrl; |
39 | int param; |
40 | }; |
41 | |
42 | static int stih407_usb2_pico_ctrl(struct stih407_usb2_picophy *phy_dev) |
43 | { |
44 | reset_control_deassert(rstc: phy_dev->rstc); |
45 | |
46 | return regmap_update_bits(map: phy_dev->regmap, reg: phy_dev->ctrl, |
47 | STIH407_USB_PICOPHY_CTRL_PORT_MASK, |
48 | STIH407_USB_PICOPHY_CTRL_PORT_CONF); |
49 | } |
50 | |
51 | static int stih407_usb2_init_port(struct phy *phy) |
52 | { |
53 | int ret; |
54 | struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy); |
55 | |
56 | stih407_usb2_pico_ctrl(phy_dev); |
57 | |
58 | ret = regmap_update_bits(map: phy_dev->regmap, |
59 | reg: phy_dev->param, |
60 | STIH407_USB_PICOPHY_PARAM_MASK, |
61 | STIH407_USB_PICOPHY_PARAM_DEF); |
62 | if (ret) |
63 | return ret; |
64 | |
65 | return reset_control_deassert(rstc: phy_dev->rstport); |
66 | } |
67 | |
68 | static int stih407_usb2_exit_port(struct phy *phy) |
69 | { |
70 | struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy); |
71 | |
72 | /* |
73 | * Only port reset is asserted, phy global reset is kept untouched |
74 | * as other ports may still be active. When all ports are in reset |
75 | * state, assumption is made that power will be cut off on the phy, in |
76 | * case of suspend for instance. Theoretically, asserting individual |
77 | * reset (like here) or global reset should be equivalent. |
78 | */ |
79 | return reset_control_assert(rstc: phy_dev->rstport); |
80 | } |
81 | |
82 | static const struct phy_ops stih407_usb2_picophy_data = { |
83 | .init = stih407_usb2_init_port, |
84 | .exit = stih407_usb2_exit_port, |
85 | .owner = THIS_MODULE, |
86 | }; |
87 | |
88 | static int stih407_usb2_picophy_probe(struct platform_device *pdev) |
89 | { |
90 | struct stih407_usb2_picophy *phy_dev; |
91 | struct device *dev = &pdev->dev; |
92 | struct device_node *np = dev->of_node; |
93 | struct phy_provider *phy_provider; |
94 | struct phy *phy; |
95 | int ret; |
96 | |
97 | phy_dev = devm_kzalloc(dev, size: sizeof(*phy_dev), GFP_KERNEL); |
98 | if (!phy_dev) |
99 | return -ENOMEM; |
100 | |
101 | phy_dev->dev = dev; |
102 | dev_set_drvdata(dev, data: phy_dev); |
103 | |
104 | phy_dev->rstc = devm_reset_control_get_shared(dev, id: "global" ); |
105 | if (IS_ERR(ptr: phy_dev->rstc)) { |
106 | dev_err(dev, "failed to ctrl picoPHY reset\n" ); |
107 | return PTR_ERR(ptr: phy_dev->rstc); |
108 | } |
109 | |
110 | phy_dev->rstport = devm_reset_control_get_exclusive(dev, id: "port" ); |
111 | if (IS_ERR(ptr: phy_dev->rstport)) { |
112 | dev_err(dev, "failed to ctrl picoPHY reset\n" ); |
113 | return PTR_ERR(ptr: phy_dev->rstport); |
114 | } |
115 | |
116 | /* Reset port by default: only deassert it in phy init */ |
117 | reset_control_assert(rstc: phy_dev->rstport); |
118 | |
119 | phy_dev->regmap = syscon_regmap_lookup_by_phandle(np, property: "st,syscfg" ); |
120 | if (IS_ERR(ptr: phy_dev->regmap)) { |
121 | dev_err(dev, "No syscfg phandle specified\n" ); |
122 | return PTR_ERR(ptr: phy_dev->regmap); |
123 | } |
124 | |
125 | ret = of_property_read_u32_index(np, propname: "st,syscfg" , PHYPARAM_REG, |
126 | out_value: &phy_dev->param); |
127 | if (ret) { |
128 | dev_err(dev, "can't get phyparam offset (%d)\n" , ret); |
129 | return ret; |
130 | } |
131 | |
132 | ret = of_property_read_u32_index(np, propname: "st,syscfg" , PHYCTRL_REG, |
133 | out_value: &phy_dev->ctrl); |
134 | if (ret) { |
135 | dev_err(dev, "can't get phyctrl offset (%d)\n" , ret); |
136 | return ret; |
137 | } |
138 | |
139 | phy = devm_phy_create(dev, NULL, ops: &stih407_usb2_picophy_data); |
140 | if (IS_ERR(ptr: phy)) { |
141 | dev_err(dev, "failed to create Display Port PHY\n" ); |
142 | return PTR_ERR(ptr: phy); |
143 | } |
144 | |
145 | phy_dev->phy = phy; |
146 | phy_set_drvdata(phy, data: phy_dev); |
147 | |
148 | phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); |
149 | if (IS_ERR(ptr: phy_provider)) |
150 | return PTR_ERR(ptr: phy_provider); |
151 | |
152 | dev_info(dev, "STiH407 USB Generic picoPHY driver probed!" ); |
153 | |
154 | return 0; |
155 | } |
156 | |
157 | static const struct of_device_id stih407_usb2_picophy_of_match[] = { |
158 | { .compatible = "st,stih407-usb2-phy" }, |
159 | { /*sentinel */ }, |
160 | }; |
161 | |
162 | MODULE_DEVICE_TABLE(of, stih407_usb2_picophy_of_match); |
163 | |
164 | static struct platform_driver stih407_usb2_picophy_driver = { |
165 | .probe = stih407_usb2_picophy_probe, |
166 | .driver = { |
167 | .name = "stih407-usb-genphy" , |
168 | .of_match_table = stih407_usb2_picophy_of_match, |
169 | } |
170 | }; |
171 | |
172 | module_platform_driver(stih407_usb2_picophy_driver); |
173 | |
174 | MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>" ); |
175 | MODULE_DESCRIPTION("STMicroelectronics Generic picoPHY driver for STiH407" ); |
176 | MODULE_LICENSE("GPL v2" ); |
177 | |