xref: /openbmc/linux/drivers/usb/host/ehci-spear.c (revision 8fdff1dc)
1 /*
2 * Driver for EHCI HCD on SPEAR SOC
3 *
4 * Copyright (C) 2010 ST Micro Electronics,
5 * Deepak Sikri <deepak.sikri@st.com>
6 *
7 * Based on various ehci-*.c drivers
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file COPYING in the main directory of this archive for
11 * more details.
12 */
13 
14 #include <linux/clk.h>
15 #include <linux/jiffies.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm.h>
19 
20 struct spear_ehci {
21 	struct ehci_hcd ehci;
22 	struct clk *clk;
23 };
24 
25 #define to_spear_ehci(hcd)	(struct spear_ehci *)hcd_to_ehci(hcd)
26 
27 static void spear_start_ehci(struct spear_ehci *ehci)
28 {
29 	clk_prepare_enable(ehci->clk);
30 }
31 
32 static void spear_stop_ehci(struct spear_ehci *ehci)
33 {
34 	clk_disable_unprepare(ehci->clk);
35 }
36 
37 static int ehci_spear_setup(struct usb_hcd *hcd)
38 {
39 	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
40 
41 	/* registers start at offset 0x0 */
42 	ehci->caps = hcd->regs;
43 
44 	return ehci_setup(hcd);
45 }
46 
47 static const struct hc_driver ehci_spear_hc_driver = {
48 	.description			= hcd_name,
49 	.product_desc			= "SPEAr EHCI",
50 	.hcd_priv_size			= sizeof(struct spear_ehci),
51 
52 	/* generic hardware linkage */
53 	.irq				= ehci_irq,
54 	.flags				= HCD_MEMORY | HCD_USB2,
55 
56 	/* basic lifecycle operations */
57 	.reset				= ehci_spear_setup,
58 	.start				= ehci_run,
59 	.stop				= ehci_stop,
60 	.shutdown			= ehci_shutdown,
61 
62 	/* managing i/o requests and associated device resources */
63 	.urb_enqueue			= ehci_urb_enqueue,
64 	.urb_dequeue			= ehci_urb_dequeue,
65 	.endpoint_disable		= ehci_endpoint_disable,
66 	.endpoint_reset			= ehci_endpoint_reset,
67 
68 	/* scheduling support */
69 	.get_frame_number		= ehci_get_frame,
70 
71 	/* root hub support */
72 	.hub_status_data		= ehci_hub_status_data,
73 	.hub_control			= ehci_hub_control,
74 	.bus_suspend			= ehci_bus_suspend,
75 	.bus_resume			= ehci_bus_resume,
76 	.relinquish_port		= ehci_relinquish_port,
77 	.port_handed_over		= ehci_port_handed_over,
78 	.clear_tt_buffer_complete	= ehci_clear_tt_buffer_complete,
79 };
80 
81 #ifdef CONFIG_PM
82 static int ehci_spear_drv_suspend(struct device *dev)
83 {
84 	struct usb_hcd *hcd = dev_get_drvdata(dev);
85 	bool do_wakeup = device_may_wakeup(dev);
86 
87 	return ehci_suspend(hcd, do_wakeup);
88 }
89 
90 static int ehci_spear_drv_resume(struct device *dev)
91 {
92 	struct usb_hcd *hcd = dev_get_drvdata(dev);
93 
94 	ehci_resume(hcd, false);
95 	return 0;
96 }
97 #endif /* CONFIG_PM */
98 
99 static SIMPLE_DEV_PM_OPS(ehci_spear_pm_ops, ehci_spear_drv_suspend,
100 		ehci_spear_drv_resume);
101 
102 static u64 spear_ehci_dma_mask = DMA_BIT_MASK(32);
103 
104 static int spear_ehci_hcd_drv_probe(struct platform_device *pdev)
105 {
106 	struct usb_hcd *hcd ;
107 	struct spear_ehci *ehci;
108 	struct resource *res;
109 	struct clk *usbh_clk;
110 	const struct hc_driver *driver = &ehci_spear_hc_driver;
111 	int irq, retval;
112 
113 	if (usb_disabled())
114 		return -ENODEV;
115 
116 	irq = platform_get_irq(pdev, 0);
117 	if (irq < 0) {
118 		retval = irq;
119 		goto fail;
120 	}
121 
122 	/*
123 	 * Right now device-tree probed devices don't get dma_mask set.
124 	 * Since shared usb code relies on it, set it here for now.
125 	 * Once we have dma capability bindings this can go away.
126 	 */
127 	if (!pdev->dev.dma_mask)
128 		pdev->dev.dma_mask = &spear_ehci_dma_mask;
129 
130 	usbh_clk = devm_clk_get(&pdev->dev, NULL);
131 	if (IS_ERR(usbh_clk)) {
132 		dev_err(&pdev->dev, "Error getting interface clock\n");
133 		retval = PTR_ERR(usbh_clk);
134 		goto fail;
135 	}
136 
137 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
138 	if (!hcd) {
139 		retval = -ENOMEM;
140 		goto fail;
141 	}
142 
143 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
144 	if (!res) {
145 		retval = -ENODEV;
146 		goto err_put_hcd;
147 	}
148 
149 	hcd->rsrc_start = res->start;
150 	hcd->rsrc_len = resource_size(res);
151 	if (!devm_request_mem_region(&pdev->dev, hcd->rsrc_start, hcd->rsrc_len,
152 				driver->description)) {
153 		retval = -EBUSY;
154 		goto err_put_hcd;
155 	}
156 
157 	hcd->regs = devm_ioremap(&pdev->dev, hcd->rsrc_start, hcd->rsrc_len);
158 	if (hcd->regs == NULL) {
159 		dev_dbg(&pdev->dev, "error mapping memory\n");
160 		retval = -ENOMEM;
161 		goto err_put_hcd;
162 	}
163 
164 	ehci = (struct spear_ehci *)hcd_to_ehci(hcd);
165 	ehci->clk = usbh_clk;
166 
167 	spear_start_ehci(ehci);
168 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
169 	if (retval)
170 		goto err_stop_ehci;
171 
172 	return retval;
173 
174 err_stop_ehci:
175 	spear_stop_ehci(ehci);
176 err_put_hcd:
177 	usb_put_hcd(hcd);
178 fail:
179 	dev_err(&pdev->dev, "init fail, %d\n", retval);
180 
181 	return retval ;
182 }
183 
184 static int spear_ehci_hcd_drv_remove(struct platform_device *pdev)
185 {
186 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
187 	struct spear_ehci *ehci_p = to_spear_ehci(hcd);
188 
189 	if (!hcd)
190 		return 0;
191 	if (in_interrupt())
192 		BUG();
193 	usb_remove_hcd(hcd);
194 
195 	if (ehci_p->clk)
196 		spear_stop_ehci(ehci_p);
197 	usb_put_hcd(hcd);
198 
199 	return 0;
200 }
201 
202 static struct of_device_id spear_ehci_id_table[] = {
203 	{ .compatible = "st,spear600-ehci", },
204 	{ },
205 };
206 
207 static struct platform_driver spear_ehci_hcd_driver = {
208 	.probe		= spear_ehci_hcd_drv_probe,
209 	.remove		= spear_ehci_hcd_drv_remove,
210 	.shutdown	= usb_hcd_platform_shutdown,
211 	.driver		= {
212 		.name = "spear-ehci",
213 		.bus = &platform_bus_type,
214 		.pm = &ehci_spear_pm_ops,
215 		.of_match_table = of_match_ptr(spear_ehci_id_table),
216 	}
217 };
218 
219 MODULE_ALIAS("platform:spear-ehci");
220