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/platform_device.h>
15 #include <linux/clk.h>
16 
17 struct spear_ehci {
18 	struct ehci_hcd ehci;
19 	struct clk *clk;
20 };
21 
22 #define to_spear_ehci(hcd)	(struct spear_ehci *)hcd_to_ehci(hcd)
23 
spear_start_ehci(struct spear_ehci * ehci)24 static void spear_start_ehci(struct spear_ehci *ehci)
25 {
26 	clk_enable(ehci->clk);
27 }
28 
spear_stop_ehci(struct spear_ehci * ehci)29 static void spear_stop_ehci(struct spear_ehci *ehci)
30 {
31 	clk_disable(ehci->clk);
32 }
33 
ehci_spear_setup(struct usb_hcd * hcd)34 static int ehci_spear_setup(struct usb_hcd *hcd)
35 {
36 	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
37 	int retval = 0;
38 
39 	/* registers start at offset 0x0 */
40 	ehci->caps = hcd->regs;
41 	ehci->regs = hcd->regs + HC_LENGTH(ehci_readl(ehci,
42 				&ehci->caps->hc_capbase));
43 	/* cache this readonly data; minimize chip reads */
44 	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
45 	retval = ehci_halt(ehci);
46 	if (retval)
47 		return retval;
48 
49 	retval = ehci_init(hcd);
50 	if (retval)
51 		return retval;
52 
53 	ehci_reset(ehci);
54 	ehci_port_power(ehci, 0);
55 
56 	return retval;
57 }
58 
59 static const struct hc_driver ehci_spear_hc_driver = {
60 	.description			= hcd_name,
61 	.product_desc			= "SPEAr EHCI",
62 	.hcd_priv_size			= sizeof(struct spear_ehci),
63 
64 	/* generic hardware linkage */
65 	.irq				= ehci_irq,
66 	.flags				= HCD_MEMORY | HCD_USB2,
67 
68 	/* basic lifecycle operations */
69 	.reset				= ehci_spear_setup,
70 	.start				= ehci_run,
71 	.stop				= ehci_stop,
72 	.shutdown			= ehci_shutdown,
73 
74 	/* managing i/o requests and associated device resources */
75 	.urb_enqueue			= ehci_urb_enqueue,
76 	.urb_dequeue			= ehci_urb_dequeue,
77 	.endpoint_disable		= ehci_endpoint_disable,
78 	.endpoint_reset			= ehci_endpoint_reset,
79 
80 	/* scheduling support */
81 	.get_frame_number		= ehci_get_frame,
82 
83 	/* root hub support */
84 	.hub_status_data		= ehci_hub_status_data,
85 	.hub_control			= ehci_hub_control,
86 	.bus_suspend			= ehci_bus_suspend,
87 	.bus_resume			= ehci_bus_resume,
88 	.relinquish_port		= ehci_relinquish_port,
89 	.port_handed_over		= ehci_port_handed_over,
90 	.clear_tt_buffer_complete	= ehci_clear_tt_buffer_complete,
91 };
92 
spear_ehci_hcd_drv_probe(struct platform_device * pdev)93 static int spear_ehci_hcd_drv_probe(struct platform_device *pdev)
94 {
95 	struct usb_hcd *hcd ;
96 	struct spear_ehci *ehci;
97 	struct resource *res;
98 	struct clk *usbh_clk;
99 	const struct hc_driver *driver = &ehci_spear_hc_driver;
100 	int *pdata = pdev->dev.platform_data;
101 	int irq, retval;
102 	char clk_name[20] = "usbh_clk";
103 
104 	if (pdata == NULL)
105 		return -EFAULT;
106 
107 	if (usb_disabled())
108 		return -ENODEV;
109 
110 	irq = platform_get_irq(pdev, 0);
111 	if (irq < 0) {
112 		retval = irq;
113 		goto fail_irq_get;
114 	}
115 
116 	if (*pdata >= 0)
117 		sprintf(clk_name, "usbh.%01d_clk", *pdata);
118 
119 	usbh_clk = clk_get(NULL, clk_name);
120 	if (IS_ERR(usbh_clk)) {
121 		dev_err(&pdev->dev, "Error getting interface clock\n");
122 		retval = PTR_ERR(usbh_clk);
123 		goto fail_get_usbh_clk;
124 	}
125 
126 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
127 	if (!hcd) {
128 		retval = -ENOMEM;
129 		goto fail_create_hcd;
130 	}
131 
132 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
133 	if (!res) {
134 		retval = -ENODEV;
135 		goto fail_request_resource;
136 	}
137 
138 	hcd->rsrc_start = res->start;
139 	hcd->rsrc_len = resource_size(res);
140 	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
141 				driver->description)) {
142 		retval = -EBUSY;
143 		goto fail_request_resource;
144 	}
145 
146 	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
147 	if (hcd->regs == NULL) {
148 		dev_dbg(&pdev->dev, "error mapping memory\n");
149 		retval = -ENOMEM;
150 		goto fail_ioremap;
151 	}
152 
153 	ehci = (struct spear_ehci *)hcd_to_ehci(hcd);
154 	ehci->clk = usbh_clk;
155 
156 	spear_start_ehci(ehci);
157 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED | IRQF_DISABLED);
158 	if (retval)
159 		goto fail_add_hcd;
160 
161 	return retval;
162 
163 fail_add_hcd:
164 	spear_stop_ehci(ehci);
165 	iounmap(hcd->regs);
166 fail_ioremap:
167 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
168 fail_request_resource:
169 	usb_put_hcd(hcd);
170 fail_create_hcd:
171 	clk_put(usbh_clk);
172 fail_get_usbh_clk:
173 fail_irq_get:
174 	dev_err(&pdev->dev, "init fail, %d\n", retval);
175 
176 	return retval ;
177 }
178 
spear_ehci_hcd_drv_remove(struct platform_device * pdev)179 static int spear_ehci_hcd_drv_remove(struct platform_device *pdev)
180 {
181 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
182 	struct spear_ehci *ehci_p = to_spear_ehci(hcd);
183 
184 	if (!hcd)
185 		return 0;
186 	if (in_interrupt())
187 		BUG();
188 	usb_remove_hcd(hcd);
189 
190 	if (ehci_p->clk)
191 		spear_stop_ehci(ehci_p);
192 	iounmap(hcd->regs);
193 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
194 	usb_put_hcd(hcd);
195 
196 	if (ehci_p->clk)
197 		clk_put(ehci_p->clk);
198 
199 	return 0;
200 }
201 
202 static struct platform_driver spear_ehci_hcd_driver = {
203 	.probe		= spear_ehci_hcd_drv_probe,
204 	.remove		= spear_ehci_hcd_drv_remove,
205 	.shutdown	= usb_hcd_platform_shutdown,
206 	.driver		= {
207 		.name = "spear-ehci",
208 		.bus = &platform_bus_type
209 	}
210 };
211 
212 MODULE_ALIAS("platform:spear-ehci");
213