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 - http://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/pm_runtime.h>
 18
 19/* USBSS register offsets */
 20#define USBSS_REVISION		0x0000
 21#define USBSS_SYSCONFIG		0x0010
 22#define USBSS_IRQ_EOI		0x0018
 23#define USBSS_IRQSTATUS_RAW_0	0x0020
 24#define USBSS_IRQSTATUS_0	0x0024
 25#define USBSS_IRQENABLE_SET_0	0x0028
 26#define USBSS_IRQENABLE_CLR_0	0x002c
 27
 28/* IRQ register bits */
 29#define USBSS_IRQ_EOI_LINE(n)	BIT(n)
 30#define USBSS_IRQ_EVENT_ST	BIT(0)
 31#define USBSS_IRQ_COREIRQ_EN	BIT(0)
 32#define USBSS_IRQ_COREIRQ_CLR	BIT(0)
 33
 34struct dwc3_keystone {
 35	struct device			*dev;
 36	void __iomem			*usbss;
 37};
 38
 39static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
 40{
 41	return readl(base + offset);
 42}
 43
 44static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
 45{
 46	writel(value, base + offset);
 47}
 48
 49static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
 50{
 51	u32 val;
 52
 53	val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
 54	val |= USBSS_IRQ_COREIRQ_EN;
 55	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
 56}
 57
 58static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
 59{
 60	u32 val;
 61
 62	val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
 63	val &= ~USBSS_IRQ_COREIRQ_EN;
 64	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
 65}
 66
 67static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
 68{
 69	struct dwc3_keystone	*kdwc = _kdwc;
 70
 71	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
 72	kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
 73	kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
 74	kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
 75
 76	return IRQ_HANDLED;
 77}
 78
 79static int kdwc3_probe(struct platform_device *pdev)
 80{
 81	struct device		*dev = &pdev->dev;
 82	struct device_node	*node = pdev->dev.of_node;
 83	struct dwc3_keystone	*kdwc;
 84	struct resource		*res;
 85	int			error, irq;
 86
 87	kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
 88	if (!kdwc)
 89		return -ENOMEM;
 90
 91	platform_set_drvdata(pdev, kdwc);
 92
 93	kdwc->dev = dev;
 94
 95	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 96	kdwc->usbss = devm_ioremap_resource(dev, res);
 97	if (IS_ERR(kdwc->usbss))
 98		return PTR_ERR(kdwc->usbss);
 99
100	pm_runtime_enable(kdwc->dev);
101
102	error = pm_runtime_get_sync(kdwc->dev);
103	if (error < 0) {
104		dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
105			error);
106		goto err_irq;
107	}
108
109	irq = platform_get_irq(pdev, 0);
110	if (irq < 0) {
111		dev_err(&pdev->dev, "missing irq\n");
112		error = irq;
113		goto err_irq;
114	}
115
116	error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
117			dev_name(dev), kdwc);
118	if (error) {
119		dev_err(dev, "failed to request IRQ #%d --> %d\n",
120				irq, error);
121		goto err_irq;
122	}
123
124	kdwc3_enable_irqs(kdwc);
125
126	error = of_platform_populate(node, NULL, NULL, dev);
127	if (error) {
128		dev_err(&pdev->dev, "failed to create dwc3 core\n");
129		goto err_core;
130	}
131
132	return 0;
133
134err_core:
135	kdwc3_disable_irqs(kdwc);
136err_irq:
137	pm_runtime_put_sync(kdwc->dev);
138	pm_runtime_disable(kdwc->dev);
139
140	return error;
141}
142
143static int kdwc3_remove_core(struct device *dev, void *c)
144{
145	struct platform_device *pdev = to_platform_device(dev);
146
147	platform_device_unregister(pdev);
148
149	return 0;
150}
151
152static int kdwc3_remove(struct platform_device *pdev)
153{
154	struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
155
156	kdwc3_disable_irqs(kdwc);
157	device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
158	pm_runtime_put_sync(kdwc->dev);
159	pm_runtime_disable(kdwc->dev);
160
161	platform_set_drvdata(pdev, NULL);
162
163	return 0;
164}
165
166static const struct of_device_id kdwc3_of_match[] = {
167	{ .compatible = "ti,keystone-dwc3", },
168	{},
169};
170MODULE_DEVICE_TABLE(of, kdwc3_of_match);
171
172static struct platform_driver kdwc3_driver = {
173	.probe		= kdwc3_probe,
174	.remove		= kdwc3_remove,
175	.driver		= {
176		.name	= "keystone-dwc3",
177		.of_match_table	= kdwc3_of_match,
178	},
179};
180
181module_platform_driver(kdwc3_driver);
182
183MODULE_ALIAS("platform:keystone-dwc3");
184MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
185MODULE_LICENSE("GPL v2");
186MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");