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 #include <linux/of_irq.h>
35 
36 /**
37  * ehci_xilinx_port_handed_over - hand the port out if failed to enable it
38  * @hcd:	Pointer to the usb_hcd device to which the host controller bound
39  * @portnum:Port number to which the device is attached.
40  *
41  * This function is used as a place to tell the user that the Xilinx USB host
42  * controller does support LS devices. And in an HS only configuration, it
43  * does not support FS devices either. It is hoped that this can help a
44  * confused user.
45  *
46  * There are cases when the host controller fails to enable the port due to,
47  * for example, insufficient power that can be supplied to the device from
48  * the USB bus. In those cases, the messages printed here are not helpful.
49  */
50 static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
51 {
52 	dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
53 	if (hcd->has_tt) {
54 		dev_warn(hcd->self.controller,
55 			"Maybe you have connected a low speed device?\n");
56 
57 		dev_warn(hcd->self.controller,
58 			"We do not support low speed devices\n");
59 	} else {
60 		dev_warn(hcd->self.controller,
61 			"Maybe your device is not a high speed device?\n");
62 		dev_warn(hcd->self.controller,
63 			"The USB host controller does not support full speed "
64 			"nor low speed devices\n");
65 		dev_warn(hcd->self.controller,
66 			"You can reconfigure the host controller to have "
67 			"full speed support\n");
68 	}
69 
70 	return 0;
71 }
72 
73 
74 static const struct hc_driver ehci_xilinx_of_hc_driver = {
75 	.description		= hcd_name,
76 	.product_desc		= "OF EHCI",
77 	.hcd_priv_size		= sizeof(struct ehci_hcd),
78 
79 	/*
80 	 * generic hardware linkage
81 	 */
82 	.irq			= ehci_irq,
83 	.flags			= HCD_MEMORY | HCD_USB2 | HCD_BH,
84 
85 	/*
86 	 * basic lifecycle operations
87 	 */
88 	.reset			= ehci_setup,
89 	.start			= ehci_run,
90 	.stop			= ehci_stop,
91 	.shutdown		= ehci_shutdown,
92 
93 	/*
94 	 * managing i/o requests and associated device resources
95 	 */
96 	.urb_enqueue		= ehci_urb_enqueue,
97 	.urb_dequeue		= ehci_urb_dequeue,
98 	.endpoint_disable	= ehci_endpoint_disable,
99 	.endpoint_reset		= ehci_endpoint_reset,
100 
101 	/*
102 	 * scheduling support
103 	 */
104 	.get_frame_number	= ehci_get_frame,
105 
106 	/*
107 	 * root hub support
108 	 */
109 	.hub_status_data	= ehci_hub_status_data,
110 	.hub_control		= ehci_hub_control,
111 #ifdef	CONFIG_PM
112 	.bus_suspend		= ehci_bus_suspend,
113 	.bus_resume		= ehci_bus_resume,
114 #endif
115 	.relinquish_port	= NULL,
116 	.port_handed_over	= ehci_xilinx_port_handed_over,
117 
118 	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
119 };
120 
121 /**
122  * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
123  * @op:		pointer to the platform_device bound to the host controller
124  *
125  * This function requests resources and sets up appropriate properties for the
126  * host controller. Because the Xilinx USB host controller can be configured
127  * as HS only or HS/FS only, it checks the configuration in the device tree
128  * entry, and sets an appropriate value for hcd->has_tt.
129  */
130 static int ehci_hcd_xilinx_of_probe(struct platform_device *op)
131 {
132 	struct device_node *dn = op->dev.of_node;
133 	struct usb_hcd *hcd;
134 	struct ehci_hcd	*ehci;
135 	struct resource res;
136 	int irq;
137 	int rv;
138 	int *value;
139 
140 	if (usb_disabled())
141 		return -ENODEV;
142 
143 	dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
144 
145 	rv = of_address_to_resource(dn, 0, &res);
146 	if (rv)
147 		return rv;
148 
149 	hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
150 				"XILINX-OF USB");
151 	if (!hcd)
152 		return -ENOMEM;
153 
154 	hcd->rsrc_start = res.start;
155 	hcd->rsrc_len = resource_size(&res);
156 
157 	irq = irq_of_parse_and_map(dn, 0);
158 	if (!irq) {
159 		dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
160 			__FILE__);
161 		rv = -EBUSY;
162 		goto err_irq;
163 	}
164 
165 	hcd->regs = devm_ioremap_resource(&op->dev, &res);
166 	if (IS_ERR(hcd->regs)) {
167 		rv = PTR_ERR(hcd->regs);
168 		goto err_irq;
169 	}
170 
171 	ehci = hcd_to_ehci(hcd);
172 
173 	/* This core always has big-endian register interface and uses
174 	 * big-endian memory descriptors.
175 	 */
176 	ehci->big_endian_mmio = 1;
177 	ehci->big_endian_desc = 1;
178 
179 	/* Check whether the FS support option is selected in the hardware.
180 	 */
181 	value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL);
182 	if (value && (*value == 1)) {
183 		ehci_dbg(ehci, "USB host controller supports FS devices\n");
184 		hcd->has_tt = 1;
185 	} else {
186 		ehci_dbg(ehci,
187 			"USB host controller is HS only\n");
188 		hcd->has_tt = 0;
189 	}
190 
191 	/* Debug registers are at the first 0x100 region
192 	 */
193 	ehci->caps = hcd->regs + 0x100;
194 
195 	rv = usb_add_hcd(hcd, irq, 0);
196 	if (rv == 0) {
197 		device_wakeup_enable(hcd->self.controller);
198 		return 0;
199 	}
200 
201 err_irq:
202 	usb_put_hcd(hcd);
203 
204 	return rv;
205 }
206 
207 /**
208  * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources
209  * @op:		pointer to platform_device structure that is to be removed
210  *
211  * Remove the hcd structure, and release resources that has been requested
212  * during probe.
213  */
214 static int ehci_hcd_xilinx_of_remove(struct platform_device *op)
215 {
216 	struct usb_hcd *hcd = platform_get_drvdata(op);
217 
218 	dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
219 
220 	usb_remove_hcd(hcd);
221 
222 	usb_put_hcd(hcd);
223 
224 	return 0;
225 }
226 
227 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
228 		{.compatible = "xlnx,xps-usb-host-1.00.a",},
229 	{},
230 };
231 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
232 
233 static struct platform_driver ehci_hcd_xilinx_of_driver = {
234 	.probe		= ehci_hcd_xilinx_of_probe,
235 	.remove		= ehci_hcd_xilinx_of_remove,
236 	.shutdown	= usb_hcd_platform_shutdown,
237 	.driver = {
238 		.name = "xilinx-of-ehci",
239 		.of_match_table = ehci_hcd_xilinx_of_match,
240 	},
241 };
242