1 // SPDX-License-Identifier: GPL-2.0
2 /**
3 * dwc3-keystone.c - Keystone Specific Glue layer
4 *
5 * Copyright (C) 2010-2013 Texas Instruments Incorporated - https://www.ti.com
6 *
7 * Author: WingMan Kwok <w-kwok2@ti.com>
8 */
9
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/io.h>
16 #include <linux/of_platform.h>
17 #include <linux/phy/phy.h>
18 #include <linux/pm_runtime.h>
19
20 /* USBSS register offsets */
21 #define USBSS_REVISION 0x0000
22 #define USBSS_SYSCONFIG 0x0010
23 #define USBSS_IRQ_EOI 0x0018
24 #define USBSS_IRQSTATUS_RAW_0 0x0020
25 #define USBSS_IRQSTATUS_0 0x0024
26 #define USBSS_IRQENABLE_SET_0 0x0028
27 #define USBSS_IRQENABLE_CLR_0 0x002c
28
29 /* IRQ register bits */
30 #define USBSS_IRQ_EOI_LINE(n) BIT(n)
31 #define USBSS_IRQ_EVENT_ST BIT(0)
32 #define USBSS_IRQ_COREIRQ_EN BIT(0)
33 #define USBSS_IRQ_COREIRQ_CLR BIT(0)
34
35 struct dwc3_keystone {
36 struct device *dev;
37 void __iomem *usbss;
38 struct phy *usb3_phy;
39 };
40
kdwc3_readl(void __iomem * base,u32 offset)41 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
42 {
43 return readl(base + offset);
44 }
45
kdwc3_writel(void __iomem * base,u32 offset,u32 value)46 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
47 {
48 writel(value, base + offset);
49 }
50
kdwc3_enable_irqs(struct dwc3_keystone * kdwc)51 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
52 {
53 u32 val;
54
55 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
56 val |= USBSS_IRQ_COREIRQ_EN;
57 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
58 }
59
kdwc3_disable_irqs(struct dwc3_keystone * kdwc)60 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
61 {
62 u32 val;
63
64 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
65 val &= ~USBSS_IRQ_COREIRQ_EN;
66 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
67 }
68
dwc3_keystone_interrupt(int irq,void * _kdwc)69 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
70 {
71 struct dwc3_keystone *kdwc = _kdwc;
72
73 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
74 kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
75 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
76 kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
77
78 return IRQ_HANDLED;
79 }
80
kdwc3_probe(struct platform_device * pdev)81 static int kdwc3_probe(struct platform_device *pdev)
82 {
83 struct device *dev = &pdev->dev;
84 struct device_node *node = pdev->dev.of_node;
85 struct dwc3_keystone *kdwc;
86 int error, irq;
87
88 kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
89 if (!kdwc)
90 return -ENOMEM;
91
92 platform_set_drvdata(pdev, kdwc);
93
94 kdwc->dev = dev;
95
96 kdwc->usbss = devm_platform_ioremap_resource(pdev, 0);
97 if (IS_ERR(kdwc->usbss))
98 return PTR_ERR(kdwc->usbss);
99
100 /* PSC dependency on AM65 needs SERDES0 to be powered before USB0 */
101 kdwc->usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
102 if (IS_ERR(kdwc->usb3_phy)) {
103 error = PTR_ERR(kdwc->usb3_phy);
104 if (error != -EPROBE_DEFER)
105 dev_err(dev, "couldn't get usb3 phy: %d\n", error);
106
107 return error;
108 }
109
110 phy_pm_runtime_get_sync(kdwc->usb3_phy);
111
112 error = phy_reset(kdwc->usb3_phy);
113 if (error < 0) {
114 dev_err(dev, "usb3 phy reset failed: %d\n", error);
115 return error;
116 }
117
118 error = phy_init(kdwc->usb3_phy);
119 if (error < 0) {
120 dev_err(dev, "usb3 phy init failed: %d\n", error);
121 return error;
122 }
123
124 error = phy_power_on(kdwc->usb3_phy);
125 if (error < 0) {
126 dev_err(dev, "usb3 phy power on failed: %d\n", error);
127 phy_exit(kdwc->usb3_phy);
128 return error;
129 }
130
131 pm_runtime_enable(kdwc->dev);
132 error = pm_runtime_get_sync(kdwc->dev);
133 if (error < 0) {
134 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
135 error);
136 goto err_irq;
137 }
138
139 /* IRQ processing not required currently for AM65 */
140 if (of_device_is_compatible(node, "ti,am654-dwc3"))
141 goto skip_irq;
142
143 irq = platform_get_irq(pdev, 0);
144 if (irq < 0) {
145 error = irq;
146 goto err_irq;
147 }
148
149 error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
150 dev_name(dev), kdwc);
151 if (error) {
152 dev_err(dev, "failed to request IRQ #%d --> %d\n",
153 irq, error);
154 goto err_irq;
155 }
156
157 kdwc3_enable_irqs(kdwc);
158
159 skip_irq:
160 error = of_platform_populate(node, NULL, NULL, dev);
161 if (error) {
162 dev_err(&pdev->dev, "failed to create dwc3 core\n");
163 goto err_core;
164 }
165
166 return 0;
167
168 err_core:
169 kdwc3_disable_irqs(kdwc);
170 err_irq:
171 pm_runtime_put_sync(kdwc->dev);
172 pm_runtime_disable(kdwc->dev);
173 phy_power_off(kdwc->usb3_phy);
174 phy_exit(kdwc->usb3_phy);
175 phy_pm_runtime_put_sync(kdwc->usb3_phy);
176
177 return error;
178 }
179
kdwc3_remove_core(struct device * dev,void * c)180 static int kdwc3_remove_core(struct device *dev, void *c)
181 {
182 struct platform_device *pdev = to_platform_device(dev);
183
184 platform_device_unregister(pdev);
185
186 return 0;
187 }
188
kdwc3_remove(struct platform_device * pdev)189 static int kdwc3_remove(struct platform_device *pdev)
190 {
191 struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
192 struct device_node *node = pdev->dev.of_node;
193
194 if (!of_device_is_compatible(node, "ti,am654-dwc3"))
195 kdwc3_disable_irqs(kdwc);
196
197 device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
198 pm_runtime_put_sync(kdwc->dev);
199 pm_runtime_disable(kdwc->dev);
200
201 phy_power_off(kdwc->usb3_phy);
202 phy_exit(kdwc->usb3_phy);
203 phy_pm_runtime_put_sync(kdwc->usb3_phy);
204
205 platform_set_drvdata(pdev, NULL);
206
207 return 0;
208 }
209
210 static const struct of_device_id kdwc3_of_match[] = {
211 { .compatible = "ti,keystone-dwc3", },
212 { .compatible = "ti,am654-dwc3" },
213 {},
214 };
215 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
216
217 static struct platform_driver kdwc3_driver = {
218 .probe = kdwc3_probe,
219 .remove = kdwc3_remove,
220 .driver = {
221 .name = "keystone-dwc3",
222 .of_match_table = kdwc3_of_match,
223 },
224 };
225
226 module_platform_driver(kdwc3_driver);
227
228 MODULE_ALIAS("platform:keystone-dwc3");
229 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
230 MODULE_LICENSE("GPL v2");
231 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
232