1 /**
2 * dwc3-keystone.c - Keystone Specific Glue layer
3 *
4 * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com
5 *
6 * Author: WingMan Kwok <w-kwok2@ti.com>
7 *
8 * This program is free software: you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 of
10 * the License as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 */
17
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/interrupt.h>
21 #include <linux/platform_device.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/io.h>
24 #include <linux/of_platform.h>
25 #include <linux/pm_runtime.h>
26
27 /* USBSS register offsets */
28 #define USBSS_REVISION 0x0000
29 #define USBSS_SYSCONFIG 0x0010
30 #define USBSS_IRQ_EOI 0x0018
31 #define USBSS_IRQSTATUS_RAW_0 0x0020
32 #define USBSS_IRQSTATUS_0 0x0024
33 #define USBSS_IRQENABLE_SET_0 0x0028
34 #define USBSS_IRQENABLE_CLR_0 0x002c
35
36 /* IRQ register bits */
37 #define USBSS_IRQ_EOI_LINE(n) BIT(n)
38 #define USBSS_IRQ_EVENT_ST BIT(0)
39 #define USBSS_IRQ_COREIRQ_EN BIT(0)
40 #define USBSS_IRQ_COREIRQ_CLR BIT(0)
41
42 struct dwc3_keystone {
43 struct device *dev;
44 void __iomem *usbss;
45 };
46
kdwc3_readl(void __iomem * base,u32 offset)47 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
48 {
49 return readl(base + offset);
50 }
51
kdwc3_writel(void __iomem * base,u32 offset,u32 value)52 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
53 {
54 writel(value, base + offset);
55 }
56
kdwc3_enable_irqs(struct dwc3_keystone * kdwc)57 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
58 {
59 u32 val;
60
61 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
62 val |= USBSS_IRQ_COREIRQ_EN;
63 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
64 }
65
kdwc3_disable_irqs(struct dwc3_keystone * kdwc)66 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
67 {
68 u32 val;
69
70 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
71 val &= ~USBSS_IRQ_COREIRQ_EN;
72 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
73 }
74
dwc3_keystone_interrupt(int irq,void * _kdwc)75 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
76 {
77 struct dwc3_keystone *kdwc = _kdwc;
78
79 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
80 kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
81 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
82 kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
83
84 return IRQ_HANDLED;
85 }
86
kdwc3_probe(struct platform_device * pdev)87 static int kdwc3_probe(struct platform_device *pdev)
88 {
89 struct device *dev = &pdev->dev;
90 struct device_node *node = pdev->dev.of_node;
91 struct dwc3_keystone *kdwc;
92 struct resource *res;
93 int error, irq;
94
95 kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
96 if (!kdwc)
97 return -ENOMEM;
98
99 platform_set_drvdata(pdev, kdwc);
100
101 kdwc->dev = dev;
102
103 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
104 kdwc->usbss = devm_ioremap_resource(dev, res);
105 if (IS_ERR(kdwc->usbss))
106 return PTR_ERR(kdwc->usbss);
107
108 pm_runtime_enable(kdwc->dev);
109
110 error = pm_runtime_get_sync(kdwc->dev);
111 if (error < 0) {
112 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
113 error);
114 goto err_irq;
115 }
116
117 irq = platform_get_irq(pdev, 0);
118 if (irq < 0) {
119 dev_err(&pdev->dev, "missing irq\n");
120 error = irq;
121 goto err_irq;
122 }
123
124 error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
125 dev_name(dev), kdwc);
126 if (error) {
127 dev_err(dev, "failed to request IRQ #%d --> %d\n",
128 irq, error);
129 goto err_irq;
130 }
131
132 kdwc3_enable_irqs(kdwc);
133
134 error = of_platform_populate(node, NULL, NULL, dev);
135 if (error) {
136 dev_err(&pdev->dev, "failed to create dwc3 core\n");
137 goto err_core;
138 }
139
140 return 0;
141
142 err_core:
143 kdwc3_disable_irqs(kdwc);
144 err_irq:
145 pm_runtime_put_sync(kdwc->dev);
146 pm_runtime_disable(kdwc->dev);
147
148 return error;
149 }
150
kdwc3_remove_core(struct device * dev,void * c)151 static int kdwc3_remove_core(struct device *dev, void *c)
152 {
153 struct platform_device *pdev = to_platform_device(dev);
154
155 platform_device_unregister(pdev);
156
157 return 0;
158 }
159
kdwc3_remove(struct platform_device * pdev)160 static int kdwc3_remove(struct platform_device *pdev)
161 {
162 struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
163
164 kdwc3_disable_irqs(kdwc);
165 device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
166 pm_runtime_put_sync(kdwc->dev);
167 pm_runtime_disable(kdwc->dev);
168
169 platform_set_drvdata(pdev, NULL);
170
171 return 0;
172 }
173
174 static const struct of_device_id kdwc3_of_match[] = {
175 { .compatible = "ti,keystone-dwc3", },
176 {},
177 };
178 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
179
180 static struct platform_driver kdwc3_driver = {
181 .probe = kdwc3_probe,
182 .remove = kdwc3_remove,
183 .driver = {
184 .name = "keystone-dwc3",
185 .of_match_table = kdwc3_of_match,
186 },
187 };
188
189 module_platform_driver(kdwc3_driver);
190
191 MODULE_ALIAS("platform:keystone-dwc3");
192 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
193 MODULE_LICENSE("GPL v2");
194 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
195