xref: /openbmc/linux/drivers/usb/dwc3/dwc3-keystone.c (revision 63705da3)
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 
41 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
42 {
43 	return readl(base + offset);
44 }
45 
46 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
47 {
48 	writel(value, base + offset);
49 }
50 
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 
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 
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 
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 
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 
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