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 return dev_err_probe(dev, PTR_ERR(kdwc->usb3_phy), "couldn't get usb3 phy\n");
104
105 phy_pm_runtime_get_sync(kdwc->usb3_phy);
106
107 error = phy_reset(kdwc->usb3_phy);
108 if (error < 0) {
109 dev_err(dev, "usb3 phy reset failed: %d\n", error);
110 return error;
111 }
112
113 error = phy_init(kdwc->usb3_phy);
114 if (error < 0) {
115 dev_err(dev, "usb3 phy init failed: %d\n", error);
116 return error;
117 }
118
119 error = phy_power_on(kdwc->usb3_phy);
120 if (error < 0) {
121 dev_err(dev, "usb3 phy power on failed: %d\n", error);
122 phy_exit(kdwc->usb3_phy);
123 return error;
124 }
125
126 pm_runtime_enable(kdwc->dev);
127 error = pm_runtime_get_sync(kdwc->dev);
128 if (error < 0) {
129 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
130 error);
131 goto err_irq;
132 }
133
134 /* IRQ processing not required currently for AM65 */
135 if (of_device_is_compatible(node, "ti,am654-dwc3"))
136 goto skip_irq;
137
138 irq = platform_get_irq(pdev, 0);
139 if (irq < 0) {
140 error = irq;
141 goto err_irq;
142 }
143
144 error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
145 dev_name(dev), kdwc);
146 if (error) {
147 dev_err(dev, "failed to request IRQ #%d --> %d\n",
148 irq, error);
149 goto err_irq;
150 }
151
152 kdwc3_enable_irqs(kdwc);
153
154 skip_irq:
155 error = of_platform_populate(node, NULL, NULL, dev);
156 if (error) {
157 dev_err(&pdev->dev, "failed to create dwc3 core\n");
158 goto err_core;
159 }
160
161 return 0;
162
163 err_core:
164 kdwc3_disable_irqs(kdwc);
165 err_irq:
166 pm_runtime_put_sync(kdwc->dev);
167 pm_runtime_disable(kdwc->dev);
168 phy_power_off(kdwc->usb3_phy);
169 phy_exit(kdwc->usb3_phy);
170 phy_pm_runtime_put_sync(kdwc->usb3_phy);
171
172 return error;
173 }
174
kdwc3_remove_core(struct device * dev,void * c)175 static int kdwc3_remove_core(struct device *dev, void *c)
176 {
177 struct platform_device *pdev = to_platform_device(dev);
178
179 platform_device_unregister(pdev);
180
181 return 0;
182 }
183
kdwc3_remove(struct platform_device * pdev)184 static int kdwc3_remove(struct platform_device *pdev)
185 {
186 struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
187 struct device_node *node = pdev->dev.of_node;
188
189 if (!of_device_is_compatible(node, "ti,am654-dwc3"))
190 kdwc3_disable_irqs(kdwc);
191
192 device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
193 pm_runtime_put_sync(kdwc->dev);
194 pm_runtime_disable(kdwc->dev);
195
196 phy_power_off(kdwc->usb3_phy);
197 phy_exit(kdwc->usb3_phy);
198 phy_pm_runtime_put_sync(kdwc->usb3_phy);
199
200 platform_set_drvdata(pdev, NULL);
201
202 return 0;
203 }
204
205 static const struct of_device_id kdwc3_of_match[] = {
206 { .compatible = "ti,keystone-dwc3", },
207 { .compatible = "ti,am654-dwc3" },
208 {},
209 };
210 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
211
212 static struct platform_driver kdwc3_driver = {
213 .probe = kdwc3_probe,
214 .remove = kdwc3_remove,
215 .driver = {
216 .name = "keystone-dwc3",
217 .of_match_table = kdwc3_of_match,
218 },
219 };
220
221 module_platform_driver(kdwc3_driver);
222
223 MODULE_ALIAS("platform:keystone-dwc3");
224 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
225 MODULE_LICENSE("GPL v2");
226 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
227