1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for EHCI HCD on SPEAr SOC
4 *
5 * Copyright (C) 2010 ST Micro Electronics,
6 * Deepak Sikri <deepak.sikri@st.com>
7 *
8 * Based on various ehci-*.c drivers
9 */
10 
11 #include <linux/clk.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/io.h>
14 #include <linux/jiffies.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm.h>
20 #include <linux/usb.h>
21 #include <linux/usb/hcd.h>
22 
23 #include "ehci.h"
24 
25 #define DRIVER_DESC "EHCI SPEAr driver"
26 
27 static const char hcd_name[] = "SPEAr-ehci";
28 
29 struct spear_ehci {
30 	struct clk *clk;
31 };
32 
33 #define to_spear_ehci(hcd)	(struct spear_ehci *)(hcd_to_ehci(hcd)->priv)
34 
35 static struct hc_driver __read_mostly ehci_spear_hc_driver;
36 
ehci_spear_drv_suspend(struct device * dev)37 static int __maybe_unused ehci_spear_drv_suspend(struct device *dev)
38 {
39 	struct usb_hcd *hcd = dev_get_drvdata(dev);
40 	bool do_wakeup = device_may_wakeup(dev);
41 
42 	return ehci_suspend(hcd, do_wakeup);
43 }
44 
ehci_spear_drv_resume(struct device * dev)45 static int __maybe_unused ehci_spear_drv_resume(struct device *dev)
46 {
47 	struct usb_hcd *hcd = dev_get_drvdata(dev);
48 
49 	ehci_resume(hcd, false);
50 	return 0;
51 }
52 
53 static SIMPLE_DEV_PM_OPS(ehci_spear_pm_ops, ehci_spear_drv_suspend,
54 		ehci_spear_drv_resume);
55 
spear_ehci_hcd_drv_probe(struct platform_device * pdev)56 static int spear_ehci_hcd_drv_probe(struct platform_device *pdev)
57 {
58 	struct usb_hcd *hcd ;
59 	struct spear_ehci *sehci;
60 	struct resource *res;
61 	struct clk *usbh_clk;
62 	const struct hc_driver *driver = &ehci_spear_hc_driver;
63 	int irq, retval;
64 
65 	if (usb_disabled())
66 		return -ENODEV;
67 
68 	irq = platform_get_irq(pdev, 0);
69 	if (irq < 0) {
70 		retval = irq;
71 		goto fail;
72 	}
73 
74 	/*
75 	 * Right now device-tree probed devices don't get dma_mask set.
76 	 * Since shared usb code relies on it, set it here for now.
77 	 * Once we have dma capability bindings this can go away.
78 	 */
79 	retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
80 	if (retval)
81 		goto fail;
82 
83 	usbh_clk = devm_clk_get(&pdev->dev, NULL);
84 	if (IS_ERR(usbh_clk)) {
85 		dev_err(&pdev->dev, "Error getting interface clock\n");
86 		retval = PTR_ERR(usbh_clk);
87 		goto fail;
88 	}
89 
90 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
91 	if (!hcd) {
92 		retval = -ENOMEM;
93 		goto fail;
94 	}
95 
96 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
97 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
98 	if (IS_ERR(hcd->regs)) {
99 		retval = PTR_ERR(hcd->regs);
100 		goto err_put_hcd;
101 	}
102 	hcd->rsrc_start = res->start;
103 	hcd->rsrc_len = resource_size(res);
104 
105 	sehci = to_spear_ehci(hcd);
106 	sehci->clk = usbh_clk;
107 
108 	/* registers start at offset 0x0 */
109 	hcd_to_ehci(hcd)->caps = hcd->regs;
110 
111 	clk_prepare_enable(sehci->clk);
112 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
113 	if (retval)
114 		goto err_stop_ehci;
115 
116 	device_wakeup_enable(hcd->self.controller);
117 	return retval;
118 
119 err_stop_ehci:
120 	clk_disable_unprepare(sehci->clk);
121 err_put_hcd:
122 	usb_put_hcd(hcd);
123 fail:
124 	dev_err(&pdev->dev, "init fail, %d\n", retval);
125 
126 	return retval ;
127 }
128 
spear_ehci_hcd_drv_remove(struct platform_device * pdev)129 static int spear_ehci_hcd_drv_remove(struct platform_device *pdev)
130 {
131 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
132 	struct spear_ehci *sehci = to_spear_ehci(hcd);
133 
134 	usb_remove_hcd(hcd);
135 
136 	if (sehci->clk)
137 		clk_disable_unprepare(sehci->clk);
138 	usb_put_hcd(hcd);
139 
140 	return 0;
141 }
142 
143 static const struct of_device_id spear_ehci_id_table[] = {
144 	{ .compatible = "st,spear600-ehci", },
145 	{ },
146 };
147 MODULE_DEVICE_TABLE(of, spear_ehci_id_table);
148 
149 static struct platform_driver spear_ehci_hcd_driver = {
150 	.probe		= spear_ehci_hcd_drv_probe,
151 	.remove		= spear_ehci_hcd_drv_remove,
152 	.shutdown	= usb_hcd_platform_shutdown,
153 	.driver		= {
154 		.name = "spear-ehci",
155 		.bus = &platform_bus_type,
156 		.pm = pm_ptr(&ehci_spear_pm_ops),
157 		.of_match_table = spear_ehci_id_table,
158 	}
159 };
160 
161 static const struct ehci_driver_overrides spear_overrides __initconst = {
162 	.extra_priv_size = sizeof(struct spear_ehci),
163 };
164 
ehci_spear_init(void)165 static int __init ehci_spear_init(void)
166 {
167 	if (usb_disabled())
168 		return -ENODEV;
169 
170 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
171 
172 	ehci_init_driver(&ehci_spear_hc_driver, &spear_overrides);
173 	return platform_driver_register(&spear_ehci_hcd_driver);
174 }
175 module_init(ehci_spear_init);
176 
ehci_spear_cleanup(void)177 static void __exit ehci_spear_cleanup(void)
178 {
179 	platform_driver_unregister(&spear_ehci_hcd_driver);
180 }
181 module_exit(ehci_spear_cleanup);
182 
183 MODULE_DESCRIPTION(DRIVER_DESC);
184 MODULE_ALIAS("platform:spear-ehci");
185 MODULE_AUTHOR("Deepak Sikri");
186 MODULE_LICENSE("GPL");
187