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 */
50static 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
74static 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 */
130static 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
201err_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 */
214static 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
227static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
228		{.compatible = "xlnx,xps-usb-host-1.00.a",},
229	{},
230};
231MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
232
233static 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