1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * EHCI HCD (Host Controller Driver) for USB.
4 *
5 * Bus Glue for Xilinx EHCI core on the of_platform bus
6 *
7 * Copyright (c) 2009 Xilinx, Inc.
8 *
9 * Based on "ehci-ppc-of.c" by Valentine Barshak <vbarshak@ru.mvista.com>
10 * and "ehci-ppc-soc.c" by Stefan Roese <sr@denx.de>
11 * and "ohci-ppc-of.c" by Sylvain Munaut <tnt@246tNt.com>
12 */
13
14 #include <linux/err.h>
15 #include <linux/signal.h>
16
17 #include <linux/of.h>
18 #include <linux/of_platform.h>
19 #include <linux/of_address.h>
20 #include <linux/of_irq.h>
21
22 /**
23 * ehci_xilinx_port_handed_over - hand the port out if failed to enable it
24 * @hcd: Pointer to the usb_hcd device to which the host controller bound
25 * @portnum:Port number to which the device is attached.
26 *
27 * This function is used as a place to tell the user that the Xilinx USB host
28 * controller does support LS devices. And in an HS only configuration, it
29 * does not support FS devices either. It is hoped that this can help a
30 * confused user.
31 *
32 * There are cases when the host controller fails to enable the port due to,
33 * for example, insufficient power that can be supplied to the device from
34 * the USB bus. In those cases, the messages printed here are not helpful.
35 *
36 * Return: Always return 0
37 */
ehci_xilinx_port_handed_over(struct usb_hcd * hcd,int portnum)38 static int ehci_xilinx_port_handed_over(struct usb_hcd *hcd, int portnum)
39 {
40 dev_warn(hcd->self.controller, "port %d cannot be enabled\n", portnum);
41 if (hcd->has_tt) {
42 dev_warn(hcd->self.controller,
43 "Maybe you have connected a low speed device?\n");
44
45 dev_warn(hcd->self.controller,
46 "We do not support low speed devices\n");
47 } else {
48 dev_warn(hcd->self.controller,
49 "Maybe your device is not a high speed device?\n");
50 dev_warn(hcd->self.controller,
51 "The USB host controller does not support full speed nor low speed devices\n");
52 dev_warn(hcd->self.controller,
53 "You can reconfigure the host controller to have full speed support\n");
54 }
55
56 return 0;
57 }
58
59
60 static const struct hc_driver ehci_xilinx_of_hc_driver = {
61 .description = hcd_name,
62 .product_desc = "OF EHCI",
63 .hcd_priv_size = sizeof(struct ehci_hcd),
64
65 /*
66 * generic hardware linkage
67 */
68 .irq = ehci_irq,
69 .flags = HCD_MEMORY | HCD_DMA | HCD_USB2 | HCD_BH,
70
71 /*
72 * basic lifecycle operations
73 */
74 .reset = ehci_setup,
75 .start = ehci_run,
76 .stop = ehci_stop,
77 .shutdown = ehci_shutdown,
78
79 /*
80 * managing i/o requests and associated device resources
81 */
82 .urb_enqueue = ehci_urb_enqueue,
83 .urb_dequeue = ehci_urb_dequeue,
84 .endpoint_disable = ehci_endpoint_disable,
85 .endpoint_reset = ehci_endpoint_reset,
86
87 /*
88 * scheduling support
89 */
90 .get_frame_number = ehci_get_frame,
91
92 /*
93 * root hub support
94 */
95 .hub_status_data = ehci_hub_status_data,
96 .hub_control = ehci_hub_control,
97 #ifdef CONFIG_PM
98 .bus_suspend = ehci_bus_suspend,
99 .bus_resume = ehci_bus_resume,
100 #endif
101 .relinquish_port = NULL,
102 .port_handed_over = ehci_xilinx_port_handed_over,
103
104 .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
105 };
106
107 /**
108 * ehci_hcd_xilinx_of_probe - Probe method for the USB host controller
109 * @op: pointer to the platform_device bound to the host controller
110 *
111 * This function requests resources and sets up appropriate properties for the
112 * host controller. Because the Xilinx USB host controller can be configured
113 * as HS only or HS/FS only, it checks the configuration in the device tree
114 * entry, and sets an appropriate value for hcd->has_tt.
115 *
116 * Return: zero on success, negative error code otherwise
117 */
ehci_hcd_xilinx_of_probe(struct platform_device * op)118 static int ehci_hcd_xilinx_of_probe(struct platform_device *op)
119 {
120 struct device_node *dn = op->dev.of_node;
121 struct usb_hcd *hcd;
122 struct ehci_hcd *ehci;
123 struct resource res;
124 int irq;
125 int rv;
126 int *value;
127
128 if (usb_disabled())
129 return -ENODEV;
130
131 dev_dbg(&op->dev, "initializing XILINX-OF USB Controller\n");
132
133 rv = of_address_to_resource(dn, 0, &res);
134 if (rv)
135 return rv;
136
137 hcd = usb_create_hcd(&ehci_xilinx_of_hc_driver, &op->dev,
138 "XILINX-OF USB");
139 if (!hcd)
140 return -ENOMEM;
141
142 hcd->rsrc_start = res.start;
143 hcd->rsrc_len = resource_size(&res);
144
145 irq = irq_of_parse_and_map(dn, 0);
146 if (!irq) {
147 dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
148 __FILE__);
149 rv = -EBUSY;
150 goto err_irq;
151 }
152
153 hcd->regs = devm_ioremap_resource(&op->dev, &res);
154 if (IS_ERR(hcd->regs)) {
155 rv = PTR_ERR(hcd->regs);
156 goto err_irq;
157 }
158
159 ehci = hcd_to_ehci(hcd);
160
161 /* This core always has big-endian register interface and uses
162 * big-endian memory descriptors.
163 */
164 ehci->big_endian_mmio = 1;
165 ehci->big_endian_desc = 1;
166
167 /* Check whether the FS support option is selected in the hardware.
168 */
169 value = (int *)of_get_property(dn, "xlnx,support-usb-fs", NULL);
170 if (value && (*value == 1)) {
171 ehci_dbg(ehci, "USB host controller supports FS devices\n");
172 hcd->has_tt = 1;
173 } else {
174 ehci_dbg(ehci,
175 "USB host controller is HS only\n");
176 hcd->has_tt = 0;
177 }
178
179 /* Debug registers are at the first 0x100 region
180 */
181 ehci->caps = hcd->regs + 0x100;
182
183 rv = usb_add_hcd(hcd, irq, 0);
184 if (rv == 0) {
185 device_wakeup_enable(hcd->self.controller);
186 return 0;
187 }
188
189 err_irq:
190 usb_put_hcd(hcd);
191
192 return rv;
193 }
194
195 /**
196 * ehci_hcd_xilinx_of_remove - shutdown hcd and release resources
197 * @op: pointer to platform_device structure that is to be removed
198 *
199 * Remove the hcd structure, and release resources that has been requested
200 * during probe.
201 *
202 * Return: Always return 0
203 */
ehci_hcd_xilinx_of_remove(struct platform_device * op)204 static void ehci_hcd_xilinx_of_remove(struct platform_device *op)
205 {
206 struct usb_hcd *hcd = platform_get_drvdata(op);
207
208 dev_dbg(&op->dev, "stopping XILINX-OF USB Controller\n");
209
210 usb_remove_hcd(hcd);
211
212 usb_put_hcd(hcd);
213 }
214
215 static const struct of_device_id ehci_hcd_xilinx_of_match[] = {
216 {.compatible = "xlnx,xps-usb-host-1.00.a",},
217 {},
218 };
219 MODULE_DEVICE_TABLE(of, ehci_hcd_xilinx_of_match);
220
221 static struct platform_driver ehci_hcd_xilinx_of_driver = {
222 .probe = ehci_hcd_xilinx_of_probe,
223 .remove_new = ehci_hcd_xilinx_of_remove,
224 .shutdown = usb_hcd_platform_shutdown,
225 .driver = {
226 .name = "xilinx-of-ehci",
227 .of_match_table = ehci_hcd_xilinx_of_match,
228 },
229 };
230