1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas RZ/V2M USB3DRD driver
4  *
5  * Copyright (C) 2022 Renesas Electronics Corporation
6  */
7 
8 #include <linux/io.h>
9 #include <linux/of_device.h>
10 #include <linux/platform_device.h>
11 #include <linux/pm_runtime.h>
12 #include <linux/reset.h>
13 #include <linux/usb/rzv2m_usb3drd.h>
14 
15 #define USB_PERI_DRD_CON	0x000
16 
17 #define USB_PERI_DRD_CON_PERI_RST	BIT(31)
18 #define USB_PERI_DRD_CON_HOST_RST	BIT(30)
19 #define USB_PERI_DRD_CON_PERI_CON	BIT(24)
20 
rzv2m_usb3drd_set_bit(struct rzv2m_usb3drd * usb3,u32 bits,u32 offs)21 static void rzv2m_usb3drd_set_bit(struct rzv2m_usb3drd *usb3, u32 bits,
22 				  u32 offs)
23 {
24 	u32 val = readl(usb3->reg + offs);
25 
26 	val |= bits;
27 	writel(val, usb3->reg + offs);
28 }
29 
rzv2m_usb3drd_clear_bit(struct rzv2m_usb3drd * usb3,u32 bits,u32 offs)30 static void rzv2m_usb3drd_clear_bit(struct rzv2m_usb3drd *usb3, u32 bits,
31 				    u32 offs)
32 {
33 	u32 val = readl(usb3->reg + offs);
34 
35 	val &= ~bits;
36 	writel(val, usb3->reg + offs);
37 }
38 
rzv2m_usb3drd_reset(struct device * dev,bool host)39 void rzv2m_usb3drd_reset(struct device *dev, bool host)
40 {
41 	struct rzv2m_usb3drd *usb3 = dev_get_drvdata(dev);
42 
43 	if (host) {
44 		rzv2m_usb3drd_clear_bit(usb3, USB_PERI_DRD_CON_PERI_CON,
45 					USB_PERI_DRD_CON);
46 		rzv2m_usb3drd_clear_bit(usb3, USB_PERI_DRD_CON_HOST_RST,
47 					USB_PERI_DRD_CON);
48 		rzv2m_usb3drd_set_bit(usb3, USB_PERI_DRD_CON_PERI_RST,
49 				      USB_PERI_DRD_CON);
50 	} else {
51 		rzv2m_usb3drd_set_bit(usb3, USB_PERI_DRD_CON_PERI_CON,
52 				      USB_PERI_DRD_CON);
53 		rzv2m_usb3drd_set_bit(usb3, USB_PERI_DRD_CON_HOST_RST,
54 				      USB_PERI_DRD_CON);
55 		rzv2m_usb3drd_clear_bit(usb3, USB_PERI_DRD_CON_PERI_RST,
56 					USB_PERI_DRD_CON);
57 	}
58 }
59 EXPORT_SYMBOL_GPL(rzv2m_usb3drd_reset);
60 
rzv2m_usb3drd_remove(struct platform_device * pdev)61 static int rzv2m_usb3drd_remove(struct platform_device *pdev)
62 {
63 	struct rzv2m_usb3drd *usb3 = platform_get_drvdata(pdev);
64 
65 	of_platform_depopulate(usb3->dev);
66 	pm_runtime_put(usb3->dev);
67 	pm_runtime_disable(&pdev->dev);
68 	reset_control_assert(usb3->drd_rstc);
69 
70 	return 0;
71 }
72 
rzv2m_usb3drd_probe(struct platform_device * pdev)73 static int rzv2m_usb3drd_probe(struct platform_device *pdev)
74 {
75 	struct rzv2m_usb3drd *usb3;
76 	int ret;
77 
78 	usb3 = devm_kzalloc(&pdev->dev, sizeof(*usb3), GFP_KERNEL);
79 	if (!usb3)
80 		return -ENOMEM;
81 
82 	usb3->dev = &pdev->dev;
83 
84 	usb3->drd_irq = platform_get_irq_byname(pdev, "drd");
85 	if (usb3->drd_irq < 0)
86 		return usb3->drd_irq;
87 
88 	usb3->reg = devm_platform_ioremap_resource(pdev, 0);
89 	if (IS_ERR(usb3->reg))
90 		return PTR_ERR(usb3->reg);
91 
92 	platform_set_drvdata(pdev, usb3);
93 
94 	usb3->drd_rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
95 	if (IS_ERR(usb3->drd_rstc))
96 		return dev_err_probe(&pdev->dev, PTR_ERR(usb3->drd_rstc),
97 				     "failed to get drd reset");
98 
99 	reset_control_deassert(usb3->drd_rstc);
100 	pm_runtime_enable(&pdev->dev);
101 	ret = pm_runtime_resume_and_get(usb3->dev);
102 	if (ret)
103 		goto err_rst;
104 
105 	ret = of_platform_populate(usb3->dev->of_node, NULL, NULL, usb3->dev);
106 	if (ret)
107 		goto err_pm;
108 
109 	return 0;
110 
111 err_pm:
112 	pm_runtime_put(usb3->dev);
113 
114 err_rst:
115 	pm_runtime_disable(&pdev->dev);
116 	reset_control_assert(usb3->drd_rstc);
117 	return ret;
118 }
119 
120 static const struct of_device_id rzv2m_usb3drd_of_match[] = {
121 	{ .compatible = "renesas,rzv2m-usb3drd", },
122 	{ /* Sentinel */ }
123 };
124 MODULE_DEVICE_TABLE(of, rzv2m_usb3drd_of_match);
125 
126 static struct platform_driver rzv2m_usb3drd_driver = {
127 	.driver = {
128 		.name = "rzv2m-usb3drd",
129 		.of_match_table = of_match_ptr(rzv2m_usb3drd_of_match),
130 	},
131 	.probe = rzv2m_usb3drd_probe,
132 	.remove = rzv2m_usb3drd_remove,
133 };
134 module_platform_driver(rzv2m_usb3drd_driver);
135 
136 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
137 MODULE_DESCRIPTION("Renesas RZ/V2M USB3DRD driver");
138 MODULE_LICENSE("GPL");
139 MODULE_ALIAS("platform:rzv2m_usb3drd");
140