xref: /linux/drivers/usb/dwc3/dwc3-keystone.c (revision 4b4193256c8d3bc3a5397b5cd9494c2ad386317d)
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 		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 
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 
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