xref: /openbmc/linux/drivers/usb/host/ehci-atmel.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Driver for EHCI UHP on Atmel chips
3  *
4  *  Copyright (C) 2009 Atmel Corporation,
5  *                     Nicolas Ferre <nicolas.ferre@atmel.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/platform_device.h>
16 
17 /* interface and function clocks */
18 static struct clk *iclk, *fclk;
19 static int clocked;
20 
21 /*-------------------------------------------------------------------------*/
22 
23 static void atmel_start_clock(void)
24 {
25 	clk_enable(iclk);
26 	clk_enable(fclk);
27 	clocked = 1;
28 }
29 
30 static void atmel_stop_clock(void)
31 {
32 	clk_disable(fclk);
33 	clk_disable(iclk);
34 	clocked = 0;
35 }
36 
37 static void atmel_start_ehci(struct platform_device *pdev)
38 {
39 	dev_dbg(&pdev->dev, "start\n");
40 	atmel_start_clock();
41 }
42 
43 static void atmel_stop_ehci(struct platform_device *pdev)
44 {
45 	dev_dbg(&pdev->dev, "stop\n");
46 	atmel_stop_clock();
47 }
48 
49 /*-------------------------------------------------------------------------*/
50 
51 static int ehci_atmel_setup(struct usb_hcd *hcd)
52 {
53 	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
54 	int retval = 0;
55 
56 	/* registers start at offset 0x0 */
57 	ehci->caps = hcd->regs;
58 	ehci->regs = hcd->regs +
59 		HC_LENGTH(ehci_readl(ehci, &ehci->caps->hc_capbase));
60 	dbg_hcs_params(ehci, "reset");
61 	dbg_hcc_params(ehci, "reset");
62 
63 	/* cache this readonly data; minimize chip reads */
64 	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
65 
66 	retval = ehci_halt(ehci);
67 	if (retval)
68 		return retval;
69 
70 	/* data structure init */
71 	retval = ehci_init(hcd);
72 	if (retval)
73 		return retval;
74 
75 	ehci->sbrn = 0x20;
76 
77 	ehci_reset(ehci);
78 	ehci_port_power(ehci, 0);
79 
80 	return retval;
81 }
82 
83 static const struct hc_driver ehci_atmel_hc_driver = {
84 	.description		= hcd_name,
85 	.product_desc		= "Atmel EHCI UHP HS",
86 	.hcd_priv_size		= sizeof(struct ehci_hcd),
87 
88 	/* generic hardware linkage */
89 	.irq			= ehci_irq,
90 	.flags			= HCD_MEMORY | HCD_USB2,
91 
92 	/* basic lifecycle operations */
93 	.reset			= ehci_atmel_setup,
94 	.start			= ehci_run,
95 	.stop			= ehci_stop,
96 	.shutdown		= ehci_shutdown,
97 
98 	/* managing i/o requests and associated device resources */
99 	.urb_enqueue		= ehci_urb_enqueue,
100 	.urb_dequeue		= ehci_urb_dequeue,
101 	.endpoint_disable	= ehci_endpoint_disable,
102 
103 	/* scheduling support */
104 	.get_frame_number	= ehci_get_frame,
105 
106 	/* root hub support */
107 	.hub_status_data	= ehci_hub_status_data,
108 	.hub_control		= ehci_hub_control,
109 	.bus_suspend		= ehci_bus_suspend,
110 	.bus_resume		= ehci_bus_resume,
111 	.relinquish_port	= ehci_relinquish_port,
112 	.port_handed_over	= ehci_port_handed_over,
113 };
114 
115 static int __init ehci_atmel_drv_probe(struct platform_device *pdev)
116 {
117 	struct usb_hcd *hcd;
118 	const struct hc_driver *driver = &ehci_atmel_hc_driver;
119 	struct resource *res;
120 	int irq;
121 	int retval;
122 
123 	if (usb_disabled())
124 		return -ENODEV;
125 
126 	pr_debug("Initializing Atmel-SoC USB Host Controller\n");
127 
128 	irq = platform_get_irq(pdev, 0);
129 	if (irq <= 0) {
130 		dev_err(&pdev->dev,
131 			"Found HC with no IRQ. Check %s setup!\n",
132 			dev_name(&pdev->dev));
133 		retval = -ENODEV;
134 		goto fail_create_hcd;
135 	}
136 
137 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
138 	if (!hcd) {
139 		retval = -ENOMEM;
140 		goto fail_create_hcd;
141 	}
142 
143 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
144 	if (!res) {
145 		dev_err(&pdev->dev,
146 			"Found HC with no register addr. Check %s setup!\n",
147 			dev_name(&pdev->dev));
148 		retval = -ENODEV;
149 		goto fail_request_resource;
150 	}
151 	hcd->rsrc_start = res->start;
152 	hcd->rsrc_len = resource_size(res);
153 
154 	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
155 				driver->description)) {
156 		dev_dbg(&pdev->dev, "controller already in use\n");
157 		retval = -EBUSY;
158 		goto fail_request_resource;
159 	}
160 
161 	hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
162 	if (hcd->regs == NULL) {
163 		dev_dbg(&pdev->dev, "error mapping memory\n");
164 		retval = -EFAULT;
165 		goto fail_ioremap;
166 	}
167 
168 	iclk = clk_get(&pdev->dev, "ehci_clk");
169 	if (IS_ERR(iclk)) {
170 		dev_err(&pdev->dev, "Error getting interface clock\n");
171 		retval = -ENOENT;
172 		goto fail_get_iclk;
173 	}
174 	fclk = clk_get(&pdev->dev, "uhpck");
175 	if (IS_ERR(fclk)) {
176 		dev_err(&pdev->dev, "Error getting function clock\n");
177 		retval = -ENOENT;
178 		goto fail_get_fclk;
179 	}
180 
181 	atmel_start_ehci(pdev);
182 
183 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
184 	if (retval)
185 		goto fail_add_hcd;
186 
187 	return retval;
188 
189 fail_add_hcd:
190 	atmel_stop_ehci(pdev);
191 	clk_put(fclk);
192 fail_get_fclk:
193 	clk_put(iclk);
194 fail_get_iclk:
195 	iounmap(hcd->regs);
196 fail_ioremap:
197 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
198 fail_request_resource:
199 	usb_put_hcd(hcd);
200 fail_create_hcd:
201 	dev_err(&pdev->dev, "init %s fail, %d\n",
202 		dev_name(&pdev->dev), retval);
203 
204 	return retval;
205 }
206 
207 static int __exit ehci_atmel_drv_remove(struct platform_device *pdev)
208 {
209 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
210 
211 	ehci_shutdown(hcd);
212 	usb_remove_hcd(hcd);
213 	iounmap(hcd->regs);
214 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
215 	usb_put_hcd(hcd);
216 
217 	atmel_stop_ehci(pdev);
218 	clk_put(fclk);
219 	clk_put(iclk);
220 	fclk = iclk = NULL;
221 
222 	return 0;
223 }
224 
225 static struct platform_driver ehci_atmel_driver = {
226 	.probe		= ehci_atmel_drv_probe,
227 	.remove		= __exit_p(ehci_atmel_drv_remove),
228 	.shutdown	= usb_hcd_platform_shutdown,
229 	.driver.name	= "atmel-ehci",
230 };
231