1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Central probing code for the FOTG210 dual role driver
4 * We register one driver for the hardware and then we decide
5 * whether to proceed with probing the host or the peripheral
6 * driver.
7 */
8 #include <linux/bitops.h>
9 #include <linux/clk.h>
10 #include <linux/device.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/regmap.h>
16 #include <linux/string_choices.h>
17 #include <linux/usb.h>
18 #include <linux/usb/otg.h>
19
20 #include "fotg210.h"
21
22 /* Role Register 0x80 */
23 #define FOTG210_RR 0x80
24 #define FOTG210_RR_ID BIT(21) /* 1 = B-device, 0 = A-device */
25 #define FOTG210_RR_CROLE BIT(20) /* 1 = device, 0 = host */
26
27 /*
28 * Gemini-specific initialization function, only executed on the
29 * Gemini SoC using the global misc control register.
30 *
31 * The gemini USB blocks are connected to either Mini-A (host mode) or
32 * Mini-B (peripheral mode) plugs. There is no role switch support on the
33 * Gemini SoC, just either-or.
34 */
35 #define GEMINI_GLOBAL_MISC_CTRL 0x30
36 #define GEMINI_MISC_USB0_WAKEUP BIT(14)
37 #define GEMINI_MISC_USB1_WAKEUP BIT(15)
38 #define GEMINI_MISC_USB0_VBUS_ON BIT(22)
39 #define GEMINI_MISC_USB1_VBUS_ON BIT(23)
40 #define GEMINI_MISC_USB0_MINI_B BIT(29)
41 #define GEMINI_MISC_USB1_MINI_B BIT(30)
42
fotg210_gemini_init(struct fotg210 * fotg,struct resource * res,enum usb_dr_mode mode)43 static int fotg210_gemini_init(struct fotg210 *fotg, struct resource *res,
44 enum usb_dr_mode mode)
45 {
46 struct device *dev = fotg->dev;
47 struct device_node *np = dev->of_node;
48 struct regmap *map;
49 bool wakeup;
50 u32 mask, val;
51 int ret;
52
53 map = syscon_regmap_lookup_by_phandle(np, "syscon");
54 if (IS_ERR(map))
55 return dev_err_probe(dev, PTR_ERR(map), "no syscon\n");
56 fotg->map = map;
57 wakeup = of_property_read_bool(np, "wakeup-source");
58
59 /*
60 * Figure out if this is USB0 or USB1 by simply checking the
61 * physical base address.
62 */
63 mask = 0;
64 if (res->start == 0x69000000) {
65 fotg->port = GEMINI_PORT_1;
66 mask = GEMINI_MISC_USB1_VBUS_ON | GEMINI_MISC_USB1_MINI_B |
67 GEMINI_MISC_USB1_WAKEUP;
68 if (mode == USB_DR_MODE_HOST)
69 val = GEMINI_MISC_USB1_VBUS_ON;
70 else
71 val = GEMINI_MISC_USB1_MINI_B;
72 if (wakeup)
73 val |= GEMINI_MISC_USB1_WAKEUP;
74 } else {
75 fotg->port = GEMINI_PORT_0;
76 mask = GEMINI_MISC_USB0_VBUS_ON | GEMINI_MISC_USB0_MINI_B |
77 GEMINI_MISC_USB0_WAKEUP;
78 if (mode == USB_DR_MODE_HOST)
79 val = GEMINI_MISC_USB0_VBUS_ON;
80 else
81 val = GEMINI_MISC_USB0_MINI_B;
82 if (wakeup)
83 val |= GEMINI_MISC_USB0_WAKEUP;
84 }
85
86 ret = regmap_update_bits(map, GEMINI_GLOBAL_MISC_CTRL, mask, val);
87 if (ret) {
88 dev_err(dev, "failed to initialize Gemini PHY\n");
89 return ret;
90 }
91
92 dev_info(dev, "initialized Gemini PHY in %s mode\n",
93 (mode == USB_DR_MODE_HOST) ? "host" : "gadget");
94 return 0;
95 }
96
97 /**
98 * fotg210_vbus() - Called by gadget driver to enable/disable VBUS
99 * @fotg: pointer to a private fotg210 object
100 * @enable: true to enable VBUS, false to disable VBUS
101 */
fotg210_vbus(struct fotg210 * fotg,bool enable)102 void fotg210_vbus(struct fotg210 *fotg, bool enable)
103 {
104 u32 mask;
105 u32 val;
106 int ret;
107
108 switch (fotg->port) {
109 case GEMINI_PORT_0:
110 mask = GEMINI_MISC_USB0_VBUS_ON;
111 val = enable ? GEMINI_MISC_USB0_VBUS_ON : 0;
112 break;
113 case GEMINI_PORT_1:
114 mask = GEMINI_MISC_USB1_VBUS_ON;
115 val = enable ? GEMINI_MISC_USB1_VBUS_ON : 0;
116 break;
117 default:
118 return;
119 }
120 ret = regmap_update_bits(fotg->map, GEMINI_GLOBAL_MISC_CTRL, mask, val);
121 if (ret)
122 dev_err(fotg->dev, "failed to %s VBUS\n",
123 str_enable_disable(enable));
124 dev_info(fotg->dev, "%s: %s VBUS\n", __func__, str_enable_disable(enable));
125 }
126
fotg210_probe(struct platform_device * pdev)127 static int fotg210_probe(struct platform_device *pdev)
128 {
129 struct device *dev = &pdev->dev;
130 enum usb_dr_mode mode;
131 struct fotg210 *fotg;
132 u32 val;
133 int ret;
134
135 fotg = devm_kzalloc(dev, sizeof(*fotg), GFP_KERNEL);
136 if (!fotg)
137 return -ENOMEM;
138 fotg->dev = dev;
139
140 fotg->base = devm_platform_get_and_ioremap_resource(pdev, 0, &fotg->res);
141 if (IS_ERR(fotg->base))
142 return PTR_ERR(fotg->base);
143
144 fotg->pclk = devm_clk_get_optional_enabled(dev, "PCLK");
145 if (IS_ERR(fotg->pclk))
146 return PTR_ERR(fotg->pclk);
147
148 mode = usb_get_dr_mode(dev);
149
150 if (of_device_is_compatible(dev->of_node, "cortina,gemini-usb")) {
151 ret = fotg210_gemini_init(fotg, fotg->res, mode);
152 if (ret)
153 return ret;
154 }
155
156 val = readl(fotg->base + FOTG210_RR);
157 if (mode == USB_DR_MODE_PERIPHERAL) {
158 if (!(val & FOTG210_RR_CROLE))
159 dev_err(dev, "block not in device role\n");
160 ret = fotg210_udc_probe(pdev, fotg);
161 } else {
162 if (val & FOTG210_RR_CROLE)
163 dev_err(dev, "block not in host role\n");
164 ret = fotg210_hcd_probe(pdev, fotg);
165 }
166
167 return ret;
168 }
169
fotg210_remove(struct platform_device * pdev)170 static void fotg210_remove(struct platform_device *pdev)
171 {
172 struct device *dev = &pdev->dev;
173 enum usb_dr_mode mode;
174
175 mode = usb_get_dr_mode(dev);
176
177 if (mode == USB_DR_MODE_PERIPHERAL)
178 fotg210_udc_remove(pdev);
179 else
180 fotg210_hcd_remove(pdev);
181 }
182
183 #ifdef CONFIG_OF
184 static const struct of_device_id fotg210_of_match[] = {
185 { .compatible = "faraday,fotg200" },
186 { .compatible = "faraday,fotg210" },
187 /* TODO: can we also handle FUSB220? */
188 {},
189 };
190 MODULE_DEVICE_TABLE(of, fotg210_of_match);
191 #endif
192
193 static struct platform_driver fotg210_driver = {
194 .driver = {
195 .name = "fotg210",
196 .of_match_table = of_match_ptr(fotg210_of_match),
197 },
198 .probe = fotg210_probe,
199 .remove = fotg210_remove,
200 };
201
fotg210_init(void)202 static int __init fotg210_init(void)
203 {
204 if (IS_ENABLED(CONFIG_USB_FOTG210_HCD) && !usb_disabled())
205 fotg210_hcd_init();
206 return platform_driver_register(&fotg210_driver);
207 }
208 module_init(fotg210_init);
209
fotg210_cleanup(void)210 static void __exit fotg210_cleanup(void)
211 {
212 platform_driver_unregister(&fotg210_driver);
213 if (IS_ENABLED(CONFIG_USB_FOTG210_HCD))
214 fotg210_hcd_cleanup();
215 }
216 module_exit(fotg210_cleanup);
217
218 MODULE_AUTHOR("Yuan-Hsin Chen, Feng-Hsin Chiang");
219 MODULE_LICENSE("GPL");
220 MODULE_DESCRIPTION("FOTG210 Dual Role Controller Driver");
221