ualea.c revision 1.4 1 /* $NetBSD: ualea.c,v 1.4 2017/04/17 16:42:07 riastradh Exp $ */
2
3 /*-
4 * Copyright (c) 2017 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Taylor R. Campbell.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: ualea.c,v 1.4 2017/04/17 16:42:07 riastradh Exp $");
34
35 #include <sys/types.h>
36 #include <sys/atomic.h>
37 #include <sys/device_if.h>
38 #include <sys/kmem.h>
39 #include <sys/rndpool.h>
40 #include <sys/rndsource.h>
41
42 #include <dev/usb/usb.h>
43 #include <dev/usb/usbdevs.h>
44 #include <dev/usb/usbdi.h>
45 #include <dev/usb/usbdi_util.h>
46
47 struct ualea_softc {
48 device_t sc_dev;
49 struct usbd_device *sc_udev;
50 struct usbd_interface *sc_uif;
51 kmutex_t sc_lock;
52 krndsource_t sc_rnd;
53 uint16_t sc_maxpktsize;
54 struct usbd_pipe *sc_pipe;
55 struct usbd_xfer *sc_xfer;
56 bool sc_attached:1;
57 bool sc_inflight:1;
58 /* lock covers sc_attached, sc_inflight, and usbd_transfer(sc_xfer) */
59 };
60
61 static int ualea_match(device_t, cfdata_t, void *);
62 static void ualea_attach(device_t, device_t, void *);
63 static int ualea_detach(device_t, int);
64 static void ualea_get(size_t, void *);
65 static void ualea_xfer_done(struct usbd_xfer *, void *, usbd_status);
66
67 CFATTACH_DECL_NEW(ualea, sizeof(struct ualea_softc),
68 ualea_match, ualea_attach, ualea_detach, NULL);
69
70 static const struct usb_devno ualea_devs[] = {
71 { USB_VENDOR_ARANEUS, USB_PRODUCT_ARANEUS_ALEA_II },
72 };
73
74 static int
75 ualea_match(device_t parent, cfdata_t match, void *aux)
76 {
77 struct usbif_attach_arg *uiaa = aux;
78
79 if (usb_lookup(ualea_devs, uiaa->uiaa_vendor, uiaa->uiaa_product))
80 return UMATCH_VENDOR_PRODUCT;
81
82 return UMATCH_NONE;
83 }
84
85 static void
86 ualea_attach(device_t parent, device_t self, void *aux)
87 {
88 struct usbif_attach_arg *uiaa = aux;
89 struct ualea_softc *sc = device_private(self);
90 struct usbd_device *udev = uiaa->uiaa_device;
91 struct usbd_interface *uif = uiaa->uiaa_iface;
92 const usb_endpoint_descriptor_t *ed;
93 char *devinfop;
94 usbd_status status;
95
96 aprint_naive("\n");
97 aprint_normal("\n");
98
99 devinfop = usbd_devinfo_alloc(udev, 0);
100 aprint_normal_dev(self, "%s\n", devinfop);
101 usbd_devinfo_free(devinfop);
102
103 sc->sc_dev = self;
104 sc->sc_udev = udev;
105 sc->sc_uif = uif;
106 mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_SOFTUSB);
107 rndsource_setcb(&sc->sc_rnd, ualea_get, sc);
108 rnd_attach_source(&sc->sc_rnd, device_xname(self), RND_TYPE_RNG,
109 RND_FLAG_COLLECT_VALUE|RND_FLAG_HASCB);
110
111 ed = usbd_interface2endpoint_descriptor(uif, 0);
112 if (ed == NULL) {
113 aprint_error_dev(sc->sc_dev, "failed to read endpoint 0\n");
114 return;
115 }
116 if (UE_GET_DIR(ed->bEndpointAddress) != UE_DIR_IN ||
117 UE_GET_XFERTYPE(ed->bmAttributes) != UE_BULK) {
118 aprint_error_dev(sc->sc_dev, "invalid endpoint\n");
119 return;
120 }
121
122 sc->sc_maxpktsize = UGETW(ed->wMaxPacketSize);
123
124 status = usbd_open_pipe(uif, ed->bEndpointAddress,
125 USBD_EXCLUSIVE_USE|USBD_MPSAFE, &sc->sc_pipe);
126 if (status) {
127 aprint_error_dev(sc->sc_dev, "failed to open pipe: %d\n",
128 status);
129 return;
130 }
131
132 status = usbd_create_xfer(sc->sc_pipe, sc->sc_maxpktsize,
133 USBD_SHORT_XFER_OK, 0, &sc->sc_xfer);
134 if (status) {
135 aprint_error_dev(sc->sc_dev, "failed to create xfer: %d\n",
136 status);
137 return;
138 }
139
140 usbd_setup_xfer(sc->sc_xfer, sc, usbd_get_buffer(sc->sc_xfer),
141 sc->sc_maxpktsize, USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT,
142 ualea_xfer_done);
143
144 /* Success! We are ready to run. */
145 mutex_enter(&sc->sc_lock);
146 sc->sc_attached = true;
147 mutex_exit(&sc->sc_lock);
148
149 /* Get some initial entropy now. */
150 ualea_get(RND_POOLBITS/NBBY, sc);
151 }
152
153 static int
154 ualea_detach(device_t self, int flags)
155 {
156 struct ualea_softc *sc = device_private(self);
157
158 /* Prevent new use of xfer. */
159 mutex_enter(&sc->sc_lock);
160 sc->sc_attached = false;
161 mutex_exit(&sc->sc_lock);
162
163 /* Cancel pending xfer. */
164 if (sc->sc_pipe)
165 (void)usbd_abort_pipe(sc->sc_pipe);
166 KASSERT(!sc->sc_inflight);
167
168 /* All users have drained. Tear it all down. */
169 if (sc->sc_xfer)
170 usbd_destroy_xfer(sc->sc_xfer);
171 if (sc->sc_pipe)
172 (void)usbd_close_pipe(sc->sc_pipe);
173 rnd_detach_source(&sc->sc_rnd);
174 mutex_destroy(&sc->sc_lock);
175
176 return 0;
177 }
178
179 static void
180 ualea_get(size_t nbytes, void *cookie)
181 {
182 struct ualea_softc *sc = cookie;
183 usbd_status status;
184
185 mutex_enter(&sc->sc_lock);
186 if (!sc->sc_attached)
187 goto out;
188 if (sc->sc_inflight)
189 goto out;
190 sc->sc_inflight = true;
191 status = usbd_transfer(sc->sc_xfer);
192 if (status && status != USBD_IN_PROGRESS) {
193 aprint_error_dev(sc->sc_dev, "failed to issue xfer: %d\n",
194 status);
195 /* We failed -- let someone else have a go. */
196 sc->sc_inflight = false;
197 }
198 out: mutex_exit(&sc->sc_lock);
199 }
200
201 static void
202 ualea_xfer_done(struct usbd_xfer *xfer, void *cookie, usbd_status status)
203 {
204 struct ualea_softc *sc = cookie;
205 void *pkt;
206 uint32_t pktsize;
207
208 /* Check the transfer status. */
209 if (status) {
210 aprint_error_dev(sc->sc_dev, "xfer failed: %d\n", status);
211 goto out;
212 }
213
214 /* Get and sanity-check the transferred size. */
215 usbd_get_xfer_status(xfer, NULL, &pkt, &pktsize, NULL);
216 if (pktsize > sc->sc_maxpktsize) {
217 aprint_error_dev(sc->sc_dev,
218 "bogus packet size: %"PRIu32" > %"PRIu16" (max), ignoring"
219 "\n",
220 pktsize, sc->sc_maxpktsize);
221 goto out;
222 }
223
224 /* Add the data to the pool. */
225 rnd_add_data(&sc->sc_rnd, pkt, pktsize, NBBY*pktsize);
226
227 out:
228 /* Allow subsequent transfers. */
229 mutex_enter(&sc->sc_lock);
230 sc->sc_inflight = false;
231 mutex_exit(&sc->sc_lock);
232 }
233