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/err.h>
29 #include <linux/signal.h>
30 
31 #include <linux/of.h>
32 #include <linux/of_platform.h>
33 #include <linux/of_address.h>
34 
35 /**
36  * ehci_xilinx_port_handed_over - hand the port out if failed to enable it
37  * @hcd:	Pointer to the usb_hcd device to which the host controller bound
38  * @portnum:Port number to which the device is attached.
39  *
40  * This function is used as a place to tell the user that the Xilinx USB host
41  * controller does support LS devices. And in an HS only configuration, it
42  * does not support FS devices either. It is hoped that this can help a
43  * confused user.
44  *
45  * There are cases when the host controller fails to enable the port due to,
46  * for example, insufficient power that can be supplied to the device from
47  * the USB bus. In those cases, the messages printed here are not helpful.
48  */
49 static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
50 {
51 	dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
52 	if (hcd->has_tt) {
53 		dev_warn(hcd->self.controller,
54 			"Maybe you have connected a low speed device?\n");
55 
56 		dev_warn(hcd->self.controller,
57 			"We do not support low speed devices\n");
58 	} else {
59 		dev_warn(hcd->self.controller,
60 			"Maybe your device is not a high speed device?\n");
61 		dev_warn(hcd->self.controller,
62 			"The USB host controller does not support full speed "
63 			"nor low speed devices\n");
64 		dev_warn(hcd->self.controller,
65 			"You can reconfigure the host controller to have "
66 			"full speed support\n");
67 	}
68 
69 	return 0;
70 }
71 
72 
73 static const struct hc_driver ehci_xilinx_of_hc_driver = {
74 	.description		= hcd_name,
75 	.product_desc		= "OF EHCI",
76 	.hcd_priv_size		= sizeof(struct ehci_hcd),
77 
78 	/*
79 	 * generic hardware linkage
80 	 */
81 	.irq			= ehci_irq,
82 	.flags			= HCD_MEMORY | HCD_USB2,
83 
84 	/*
85 	 * basic lifecycle operations
86 	 */
87 	.reset			= ehci_setup,
88 	.start			= ehci_run,
89 	.stop			= ehci_stop,
90 	.shutdown		= ehci_shutdown,
91 
92 	/*
93 	 * managing i/o requests and associated device resources
94 	 */
95 	.urb_enqueue		= ehci_urb_enqueue,
96 	.urb_dequeue		= ehci_urb_dequeue,
97 	.endpoint_disable	= ehci_endpoint_disable,
98 	.endpoint_reset		= ehci_endpoint_reset,
99 
100 	/*
101 	 * scheduling support
102 	 */
103 	.get_frame_number	= ehci_get_frame,
104 
105 	/*
106 	 * root hub support
107 	 */
108 	.hub_status_data	= ehci_hub_status_data,
109 	.hub_control		= ehci_hub_control,
110 #ifdef	CONFIG_PM
111 	.bus_suspend		= ehci_bus_suspend,
112 	.bus_resume		= ehci_bus_resume,
113 #endif
114 	.relinquish_port	= NULL,
115 	.port_handed_over	= ehci_xilinx_port_handed_over,
116 
117 	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
118 };
119 
120 /**
121  * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
122  * @op:		pointer to the platform_device bound to the host controller
123  *
124  * This function requests resources and sets up appropriate properties for the
125  * host controller. Because the Xilinx USB host controller can be configured
126  * as HS only or HS/FS only, it checks the configuration in the device tree
127  * entry, and sets an appropriate value for hcd->has_tt.
128  */
129 static int ehci_hcd_xilinx_of_probe(struct platform_device *op)
130 {
131 	struct device_node *dn = op->dev.of_node;
132 	struct usb_hcd *hcd;
133 	struct ehci_hcd	*ehci;
134 	struct resource res;
135 	int irq;
136 	int rv;
137 	int *value;
138 
139 	if (usb_disabled())
140 		return -ENODEV;
141 
142 	dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
143 
144 	rv = of_address_to_resource(dn, 0, &res);
145 	if (rv)
146 		return rv;
147 
148 	hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
149 				"XILINX-OF USB");
150 	if (!hcd)
151 		return -ENOMEM;
152 
153 	hcd->rsrc_start = res.start;
154 	hcd->rsrc_len = resource_size(&res);
155 
156 	irq = irq_of_parse_and_map(dn, 0);
157 	if (!irq) {
158 		printk(KERN_ERR "%s: irq_of_parse_and_map failed\n", __FILE__);
159 		rv = -EBUSY;
160 		goto err_irq;
161 	}
162 
163 	hcd->regs = devm_ioremap_resource(&op->dev, &res);
164 	if (IS_ERR(hcd->regs)) {
165 		rv = PTR_ERR(hcd->regs);
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 = platform_get_drvdata(op);
213 
214 	dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
215 
216 	usb_remove_hcd(hcd);
217 
218 	usb_put_hcd(hcd);
219 
220 	return 0;
221 }
222 
223 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
224 		{.compatible = "xlnx,xps-usb-host-1.00.a",},
225 	{},
226 };
227 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
228 
229 static struct platform_driver ehci_hcd_xilinx_of_driver = {
230 	.probe		= ehci_hcd_xilinx_of_probe,
231 	.remove		= ehci_hcd_xilinx_of_remove,
232 	.shutdown	= usb_hcd_platform_shutdown,
233 	.driver = {
234 		.name = "xilinx-of-ehci",
235 		.owner = THIS_MODULE,
236 		.of_match_table = ehci_hcd_xilinx_of_match,
237 	},
238 };
239