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