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_port_handed_over - hand the port out if failed to enable it
36  * @hcd:	Pointer to the usb_hcd device to which the host controller bound
37  * @portnum:Port number to which the device is attached.
38  *
39  * This function is used as a place to tell the user that the Xilinx USB host
40  * controller does support LS devices. And in an HS only configuration, it
41  * does not support FS devices either. It is hoped that this can help a
42  * confused user.
43  *
44  * There are cases when the host controller fails to enable the port due to,
45  * for example, insufficient power that can be supplied to the device from
46  * the USB bus. In those cases, the messages printed here are not helpful.
47  */
48 static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
49 {
50 	dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
51 	if (hcd->has_tt) {
52 		dev_warn(hcd->self.controller,
53 			"Maybe you have connected a low speed device?\n");
54 
55 		dev_warn(hcd->self.controller,
56 			"We do not support low speed devices\n");
57 	} else {
58 		dev_warn(hcd->self.controller,
59 			"Maybe your device is not a high speed device?\n");
60 		dev_warn(hcd->self.controller,
61 			"The USB host controller does not support full speed "
62 			"nor low speed devices\n");
63 		dev_warn(hcd->self.controller,
64 			"You can reconfigure the host controller to have "
65 			"full speed support\n");
66 	}
67 
68 	return 0;
69 }
70 
71 
72 static const struct hc_driver ehci_xilinx_of_hc_driver = {
73 	.description		= hcd_name,
74 	.product_desc		= "OF EHCI",
75 	.hcd_priv_size		= sizeof(struct ehci_hcd),
76 
77 	/*
78 	 * generic hardware linkage
79 	 */
80 	.irq			= ehci_irq,
81 	.flags			= HCD_MEMORY | HCD_USB2,
82 
83 	/*
84 	 * basic lifecycle operations
85 	 */
86 	.reset			= ehci_setup,
87 	.start			= ehci_run,
88 	.stop			= ehci_stop,
89 	.shutdown		= ehci_shutdown,
90 
91 	/*
92 	 * managing i/o requests and associated device resources
93 	 */
94 	.urb_enqueue		= ehci_urb_enqueue,
95 	.urb_dequeue		= ehci_urb_dequeue,
96 	.endpoint_disable	= ehci_endpoint_disable,
97 	.endpoint_reset		= ehci_endpoint_reset,
98 
99 	/*
100 	 * scheduling support
101 	 */
102 	.get_frame_number	= ehci_get_frame,
103 
104 	/*
105 	 * root hub support
106 	 */
107 	.hub_status_data	= ehci_hub_status_data,
108 	.hub_control		= ehci_hub_control,
109 #ifdef	CONFIG_PM
110 	.bus_suspend		= ehci_bus_suspend,
111 	.bus_resume		= ehci_bus_resume,
112 #endif
113 	.relinquish_port	= NULL,
114 	.port_handed_over	= ehci_xilinx_port_handed_over,
115 
116 	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
117 };
118 
119 /**
120  * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
121  * @op:		pointer to the platform_device bound to the host controller
122  *
123  * This function requests resources and sets up appropriate properties for the
124  * host controller. Because the Xilinx USB host controller can be configured
125  * as HS only or HS/FS only, it checks the configuration in the device tree
126  * entry, and sets an appropriate value for hcd->has_tt.
127  */
128 static int __devinit ehci_hcd_xilinx_of_probe(struct platform_device *op)
129 {
130 	struct device_node *dn = op->dev.of_node;
131 	struct usb_hcd *hcd;
132 	struct ehci_hcd	*ehci;
133 	struct resource res;
134 	int irq;
135 	int rv;
136 	int *value;
137 
138 	if (usb_disabled())
139 		return -ENODEV;
140 
141 	dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
142 
143 	rv = of_address_to_resource(dn, 0, &res);
144 	if (rv)
145 		return rv;
146 
147 	hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
148 				"XILINX-OF USB");
149 	if (!hcd)
150 		return -ENOMEM;
151 
152 	hcd->rsrc_start = res.start;
153 	hcd->rsrc_len = resource_size(&res);
154 
155 	irq = irq_of_parse_and_map(dn, 0);
156 	if (!irq) {
157 		printk(KERN_ERR "%s: irq_of_parse_and_map failed\n", __FILE__);
158 		rv = -EBUSY;
159 		goto err_irq;
160 	}
161 
162 	hcd->regs = devm_request_and_ioremap(&op->dev, &res);
163 	if (!hcd->regs) {
164 		pr_err("%s: devm_request_and_ioremap failed\n", __FILE__);
165 		rv = -ENOMEM;
166 		goto err_irq;
167 	}
168 
169 	ehci = hcd_to_ehci(hcd);
170 
171 	/* This core always has big-endian register interface and uses
172 	 * big-endian memory descriptors.
173 	 */
174 	ehci->big_endian_mmio = 1;
175 	ehci->big_endian_desc = 1;
176 
177 	/* Check whether the FS support option is selected in the hardware.
178 	 */
179 	value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL);
180 	if (value && (*value == 1)) {
181 		ehci_dbg(ehci, "USB host controller supports FS devices\n");
182 		hcd->has_tt = 1;
183 	} else {
184 		ehci_dbg(ehci,
185 			"USB host controller is HS only\n");
186 		hcd->has_tt = 0;
187 	}
188 
189 	/* Debug registers are at the first 0x100 region
190 	 */
191 	ehci->caps = hcd->regs + 0x100;
192 
193 	rv = usb_add_hcd(hcd, irq, 0);
194 	if (rv == 0)
195 		return 0;
196 
197 err_irq:
198 	usb_put_hcd(hcd);
199 
200 	return rv;
201 }
202 
203 /**
204  * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources
205  * @op:		pointer to platform_device structure that is to be removed
206  *
207  * Remove the hcd structure, and release resources that has been requested
208  * during probe.
209  */
210 static int ehci_hcd_xilinx_of_remove(struct platform_device *op)
211 {
212 	struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
213 	dev_set_drvdata(&op->dev, NULL);
214 
215 	dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
216 
217 	usb_remove_hcd(hcd);
218 
219 	usb_put_hcd(hcd);
220 
221 	return 0;
222 }
223 
224 /**
225  * ehci_hcd_xilinx_of_shutdown - shutdown the hcd
226  * @op:		pointer to platform_device structure that is to be removed
227  *
228  * Properly shutdown the hcd, call driver's shutdown routine.
229  */
230 static void ehci_hcd_xilinx_of_shutdown(struct platform_device *op)
231 {
232 	struct usb_hcd *hcd = dev_get_drvdata(&op->dev);
233 
234 	if (hcd->driver->shutdown)
235 		hcd->driver->shutdown(hcd);
236 }
237 
238 
239 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
240 		{.compatible = "xlnx,xps-usb-host-1.00.a",},
241 	{},
242 };
243 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
244 
245 static struct platform_driver ehci_hcd_xilinx_of_driver = {
246 	.probe		= ehci_hcd_xilinx_of_probe,
247 	.remove		= ehci_hcd_xilinx_of_remove,
248 	.shutdown	= ehci_hcd_xilinx_of_shutdown,
249 	.driver = {
250 		.name = "xilinx-of-ehci",
251 		.owner = THIS_MODULE,
252 		.of_match_table = ehci_hcd_xilinx_of_match,
253 	},
254 };
255