summaryrefslogtreecommitdiffstats
path: root/drivers/usb/dwc3/dwc3-keystone.c
blob: 1fad1618df6e8b742785635e8582fd9663d65d54 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/**
 * dwc3-keystone.c - Keystone Specific Glue layer
 *
 * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com
 *
 * Author: WingMan Kwok <w-kwok2@ti.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2  of
 * the License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/clk.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/of_platform.h>

/* USBSS register offsets */
#define USBSS_REVISION		0x0000
#define USBSS_SYSCONFIG		0x0010
#define USBSS_IRQ_EOI		0x0018
#define USBSS_IRQSTATUS_RAW_0	0x0020
#define USBSS_IRQSTATUS_0	0x0024
#define USBSS_IRQENABLE_SET_0	0x0028
#define USBSS_IRQENABLE_CLR_0	0x002c

/* IRQ register bits */
#define USBSS_IRQ_EOI_LINE(n)	BIT(n)
#define USBSS_IRQ_EVENT_ST	BIT(0)
#define USBSS_IRQ_COREIRQ_EN	BIT(0)
#define USBSS_IRQ_COREIRQ_CLR	BIT(0)

static u64 kdwc3_dma_mask;

struct dwc3_keystone {
	struct device			*dev;
	struct clk			*clk;
	void __iomem			*usbss;
};

static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
{
	return readl(base + offset);
}

static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
{
	writel(value, base + offset);
}

static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
{
	u32 val;

	val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
	val |= USBSS_IRQ_COREIRQ_EN;
	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
}

static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
{
	u32 val;

	val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
	val &= ~USBSS_IRQ_COREIRQ_EN;
	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
}

static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
{
	struct dwc3_keystone	*kdwc = _kdwc;

	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
	kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
	kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));

	return IRQ_HANDLED;
}

static int kdwc3_probe(struct platform_device *pdev)
{
	struct device		*dev = &pdev->dev;
	struct device_node	*node = pdev->dev.of_node;
	struct dwc3_keystone	*kdwc;
	struct resource		*res;
	int			error, irq;

	kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
	if (!kdwc)
		return -ENOMEM;

	platform_set_drvdata(pdev, kdwc);

	kdwc->dev = dev;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(dev, "missing usbss resource\n");
		return -EINVAL;
	}

	kdwc->usbss = devm_ioremap_resource(dev, res);
	if (IS_ERR(kdwc->usbss))
		return PTR_ERR(kdwc->usbss);

	kdwc3_dma_mask = dma_get_mask(dev);
	dev->dma_mask = &kdwc3_dma_mask;

	kdwc->clk = devm_clk_get(kdwc->dev, "usb");

	error = clk_prepare_enable(kdwc->clk);
	if (error < 0) {
		dev_dbg(kdwc->dev, "unable to enable usb clock, err %d\n",
			error);
		return error;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "missing irq\n");
		goto err_irq;
	}

	error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
			dev_name(dev), kdwc);
	if (error) {
		dev_err(dev, "failed to request IRQ #%d --> %d\n",
				irq, error);
		goto err_irq;
	}

	kdwc3_enable_irqs(kdwc);

	error = of_platform_populate(node, NULL, NULL, dev);
	if (error) {
		dev_err(&pdev->dev, "failed to create dwc3 core\n");
		goto err_core;
	}

	return 0;

err_core:
	kdwc3_disable_irqs(kdwc);
err_irq:
	clk_disable_unprepare(kdwc->clk);

	return error;
}

static int kdwc3_remove_core(struct device *dev, void *c)
{
	struct platform_device *pdev = to_platform_device(dev);

	platform_device_unregister(pdev);

	return 0;
}

static int kdwc3_remove(struct platform_device *pdev)
{
	struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);

	kdwc3_disable_irqs(kdwc);
	device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
	clk_disable_unprepare(kdwc->clk);
	platform_set_drvdata(pdev, NULL);

	return 0;
}

static const struct of_device_id kdwc3_of_match[] = {
	{ .compatible = "ti,keystone-dwc3", },
	{},
};
MODULE_DEVICE_TABLE(of, kdwc3_of_match);

static struct platform_driver kdwc3_driver = {
	.probe		= kdwc3_probe,
	.remove		= kdwc3_remove,
	.driver		= {
		.name	= "keystone-dwc3",
		.owner	        = THIS_MODULE,
		.of_match_table	= kdwc3_of_match,
	},
};

module_platform_driver(kdwc3_driver);

MODULE_ALIAS("platform:keystone-dwc3");
MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
OpenPOWER on IntegriCloud