1 /*
2  * EHCI HCD (Host Controller Driver) for USB.
3  *
4  * Bus Glue for Xilinx EHCI core on the of_platform bus
5  *
6  * Copyright (c) 2009 Xilinx, Inc.
7  *
8  * Based on "ehci-ppc-of.c" by Valentine Barshak <vbarshak@ru.mvista.com>
9  * and "ehci-ppc-soc.c" by Stefan Roese <sr@denx.de>
10  * and "ohci-ppc-of.c" by Sylvain Munaut <tnt@246tNt.com>
11  *
12  * This program is free software; you can redistribute it and/or modify it
13  * under the terms of the GNU General Public License as published by the
14  * Free Software Foundation; either version 2 of the License, or (at your
15  * option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful, but
18  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
19  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
20  * for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software Foundation,
24  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  */
27 
28 #include <linux/signal.h>
29 
30 #include <linux/of.h>
31 #include <linux/of_platform.h>
32 #include <linux/of_address.h>
33 
34 /**
35  * ehci_xilinx_of_setup - Initialize the device for ehci_reset()
36  * @hcd:	Pointer to the usb_hcd device to which the host controller bound
37  *
38  * called during probe() after chip reset completes.
39  */
40 static int ehci_xilinx_of_setup(struct usb_hcd *hcd)
41 {
42 	struct ehci_hcd	*ehci = hcd_to_ehci(hcd);
43 	int		retval;
44 
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->sbrn = 0x20;
54 
55 	return ehci_reset(ehci);
56 }
57 
58 /**
59  * ehci_xilinx_port_handed_over - hand the port out if failed to enable it
60  * @hcd:	Pointer to the usb_hcd device to which the host controller bound
61  * @portnum:Port number to which the device is attached.
62  *
63  * This function is used as a place to tell the user that the Xilinx USB host
64  * controller does support LS devices. And in an HS only configuration, it
65  * does not support FS devices either. It is hoped that this can help a
66  * confused user.
67  *
68  * There are cases when the host controller fails to enable the port due to,
69  * for example, insufficient power that can be supplied to the device from
70  * the USB bus. In those cases, the messages printed here are not helpful.
71  */
72 static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
73 {
74 	dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
75 	if (hcd->has_tt) {
76 		dev_warn(hcd->self.controller,
77 			"Maybe you have connected a low speed device?\n");
78 
79 		dev_warn(hcd->self.controller,
80 			"We do not support low speed devices\n");
81 	} else {
82 		dev_warn(hcd->self.controller,
83 			"Maybe your device is not a high speed device?\n");
84 		dev_warn(hcd->self.controller,
85 			"The USB host controller does not support full speed "
86 			"nor low speed devices\n");
87 		dev_warn(hcd->self.controller,
88 			"You can reconfigure the host controller to have "
89 			"full speed support\n");
90 	}
91 
92 	return 0;
93 }
94 
95 
96 static const struct hc_driver ehci_xilinx_of_hc_driver = {
97 	.description		= hcd_name,
98 	.product_desc		= "OF EHCI",
99 	.hcd_priv_size		= sizeof(struct ehci_hcd),
100 
101 	/*
102 	 * generic hardware linkage
103 	 */
104 	.irq			= ehci_irq,
105 	.flags			= HCD_MEMORY | HCD_USB2,
106 
107 	/*
108 	 * basic lifecycle operations
109 	 */
110 	.reset			= ehci_xilinx_of_setup,
111 	.start			= ehci_run,
112 	.stop			= ehci_stop,
113 	.shutdown		= ehci_shutdown,
114 
115 	/*
116 	 * managing i/o requests and associated device resources
117 	 */
118 	.urb_enqueue		= ehci_urb_enqueue,
119 	.urb_dequeue		= ehci_urb_dequeue,
120 	.endpoint_disable	= ehci_endpoint_disable,
121 	.endpoint_reset		= ehci_endpoint_reset,
122 
123 	/*
124 	 * scheduling support
125 	 */
126 	.get_frame_number	= ehci_get_frame,
127 
128 	/*
129 	 * root hub support
130 	 */
131 	.hub_status_data	= ehci_hub_status_data,
132 	.hub_control		= ehci_hub_control,
133 #ifdef	CONFIG_PM
134 	.bus_suspend		= ehci_bus_suspend,
135 	.bus_resume		= ehci_bus_resume,
136 #endif
137 	.relinquish_port	= NULL,
138 	.port_handed_over	= ehci_xilinx_port_handed_over,
139 
140 	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
141 };
142 
143 /**
144  * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
145  * @op:		pointer to the platform_device bound to the host controller
146  *
147  * This function requests resources and sets up appropriate properties for the
148  * host controller. Because the Xilinx USB host controller can be configured
149  * as HS only or HS/FS only, it checks the configuration in the device tree
150  * entry, and sets an appropriate value for hcd->has_tt.
151  */
152 static int __devinit ehci_hcd_xilinx_of_probe(struct platform_device *op)
153 {
154 	struct device_node *dn = op->dev.of_node;
155 	struct usb_hcd *hcd;
156 	struct ehci_hcd	*ehci;
157 	struct resource res;
158 	int irq;
159 	int rv;
160 	int *value;
161 
162 	if (usb_disabled())
163 		return -ENODEV;
164 
165 	dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
166 
167 	rv = of_address_to_resource(dn, 0, &res);
168 	if (rv)
169 		return rv;
170 
171 	hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
172 				"XILINX-OF USB");
173 	if (!hcd)
174 		return -ENOMEM;
175 
176 	hcd->rsrc_start = res.start;
177 	hcd->rsrc_len = resource_size(&res);
178 
179 	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, hcd_name)) {
180 		printk(KERN_ERR "%s: request_mem_region failed\n", __FILE__);
181 		rv = -EBUSY;
182 		goto err_rmr;
183 	}
184 
185 	irq = irq_of_parse_and_map(dn, 0);
186 	if (!irq) {
187 		printk(KERN_ERR "%s: irq_of_parse_and_map failed\n", __FILE__);
188 		rv = -EBUSY;
189 		goto err_irq;
190 	}
191 
192 	hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
193 	if (!hcd->regs) {
194 		printk(KERN_ERR "%s: ioremap failed\n", __FILE__);
195 		rv = -ENOMEM;
196 		goto err_ioremap;
197 	}
198 
199 	ehci = hcd_to_ehci(hcd);
200 
201 	/* This core always has big-endian register interface and uses
202 	 * big-endian memory descriptors.
203 	 */
204 	ehci->big_endian_mmio = 1;
205 	ehci->big_endian_desc = 1;
206 
207 	/* Check whether the FS support option is selected in the hardware.
208 	 */
209 	value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL);
210 	if (value && (*value == 1)) {
211 		ehci_dbg(ehci, "USB host controller supports FS devices\n");
212 		hcd->has_tt = 1;
213 	} else {
214 		ehci_dbg(ehci,
215 			"USB host controller is HS only\n");
216 		hcd->has_tt = 0;
217 	}
218 
219 	/* Debug registers are at the first 0x100 region
220 	 */
221 	ehci->caps = hcd->regs + 0x100;
222 	ehci->regs = hcd->regs + 0x100 +
223 		HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
224 
225 	/* cache this readonly data; minimize chip reads */
226 	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
227 
228 	rv = usb_add_hcd(hcd, irq, 0);
229 	if (rv == 0)
230 		return 0;
231 
232 	iounmap(hcd->regs);
233 
234 err_ioremap:
235 err_irq:
236 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
237 err_rmr:
238 	usb_put_hcd(hcd);
239 
240 	return rv;
241 }
242 
243 /**
244  * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources
245  * @op:		pointer to platform_device structure that is to be removed
246  *
247  * Remove the hcd structure, and release resources that has been requested
248  * during probe.
249  */
250 static int ehci_hcd_xilinx_of_remove(struct platform_device *op)
251 {
252 	struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
253 	dev_set_drvdata(&op->dev, NULL);
254 
255 	dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
256 
257 	usb_remove_hcd(hcd);
258 
259 	iounmap(hcd->regs);
260 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
261 
262 	usb_put_hcd(hcd);
263 
264 	return 0;
265 }
266 
267 /**
268  * ehci_hcd_xilinx_of_shutdown - shutdown the hcd
269  * @op:		pointer to platform_device structure that is to be removed
270  *
271  * Properly shutdown the hcd, call driver's shutdown routine.
272  */
273 static int ehci_hcd_xilinx_of_shutdown(struct platform_device *op)
274 {
275 	struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
276 
277 	if (hcd->driver->shutdown)
278 		hcd->driver->shutdown(hcd);
279 
280 	return 0;
281 }
282 
283 
284 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
285 		{.compatible = "xlnx,xps-usb-host-1.00.a",},
286 	{},
287 };
288 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
289 
290 static struct platform_driver ehci_hcd_xilinx_of_driver = {
291 	.probe		= ehci_hcd_xilinx_of_probe,
292 	.remove		= ehci_hcd_xilinx_of_remove,
293 	.shutdown	= ehci_hcd_xilinx_of_shutdown,
294 	.driver = {
295 		.name = "xilinx-of-ehci",
296 		.owner = THIS_MODULE,
297 		.of_match_table = ehci_hcd_xilinx_of_match,
298 	},
299 };
300