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-rw-r--r--Documentation/timers/hpet.txt273
1 files changed, 2 insertions, 271 deletions
diff --git a/Documentation/timers/hpet.txt b/Documentation/timers/hpet.txt
index 16d25e6b5a00..767392ffd31e 100644
--- a/Documentation/timers/hpet.txt
+++ b/Documentation/timers/hpet.txt
@@ -26,274 +26,5 @@ initialization. An example of this initialization can be found in
26arch/x86/kernel/hpet.c. 26arch/x86/kernel/hpet.c.
27 27
28The driver provides a userspace API which resembles the API found in the 28The driver provides a userspace API which resembles the API found in the
29RTC driver framework. An example user space program is provided below. 29RTC driver framework. An example user space program is provided in
30 30file:Documentation/timers/hpet_example.c
31#include <stdio.h>
32#include <stdlib.h>
33#include <unistd.h>
34#include <fcntl.h>
35#include <string.h>
36#include <memory.h>
37#include <malloc.h>
38#include <time.h>
39#include <ctype.h>
40#include <sys/types.h>
41#include <sys/wait.h>
42#include <signal.h>
43#include <fcntl.h>
44#include <errno.h>
45#include <sys/time.h>
46#include <linux/hpet.h>
47
48
49extern void hpet_open_close(int, const char **);
50extern void hpet_info(int, const char **);
51extern void hpet_poll(int, const char **);
52extern void hpet_fasync(int, const char **);
53extern void hpet_read(int, const char **);
54
55#include <sys/poll.h>
56#include <sys/ioctl.h>
57#include <signal.h>
58
59struct hpet_command {
60 char *command;
61 void (*func)(int argc, const char ** argv);
62} hpet_command[] = {
63 {
64 "open-close",
65 hpet_open_close
66 },
67 {
68 "info",
69 hpet_info
70 },
71 {
72 "poll",
73 hpet_poll
74 },
75 {
76 "fasync",
77 hpet_fasync
78 },
79};
80
81int
82main(int argc, const char ** argv)
83{
84 int i;
85
86 argc--;
87 argv++;
88
89 if (!argc) {
90 fprintf(stderr, "-hpet: requires command\n");
91 return -1;
92 }
93
94
95 for (i = 0; i < (sizeof (hpet_command) / sizeof (hpet_command[0])); i++)
96 if (!strcmp(argv[0], hpet_command[i].command)) {
97 argc--;
98 argv++;
99 fprintf(stderr, "-hpet: executing %s\n",
100 hpet_command[i].command);
101 hpet_command[i].func(argc, argv);
102 return 0;
103 }
104
105 fprintf(stderr, "do_hpet: command %s not implemented\n", argv[0]);
106
107 return -1;
108}
109
110void
111hpet_open_close(int argc, const char **argv)
112{
113 int fd;
114
115 if (argc != 1) {
116 fprintf(stderr, "hpet_open_close: device-name\n");
117 return;
118 }
119
120 fd = open(argv[0], O_RDONLY);
121 if (fd < 0)
122 fprintf(stderr, "hpet_open_close: open failed\n");
123 else
124 close(fd);
125
126 return;
127}
128
129void
130hpet_info(int argc, const char **argv)
131{
132}
133
134void
135hpet_poll(int argc, const char **argv)
136{
137 unsigned long freq;
138 int iterations, i, fd;
139 struct pollfd pfd;
140 struct hpet_info info;
141 struct timeval stv, etv;
142 struct timezone tz;
143 long usec;
144
145 if (argc != 3) {
146 fprintf(stderr, "hpet_poll: device-name freq iterations\n");
147 return;
148 }
149
150 freq = atoi(argv[1]);
151 iterations = atoi(argv[2]);
152
153 fd = open(argv[0], O_RDONLY);
154
155 if (fd < 0) {
156 fprintf(stderr, "hpet_poll: open of %s failed\n", argv[0]);
157 return;
158 }
159
160 if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
161 fprintf(stderr, "hpet_poll: HPET_IRQFREQ failed\n");
162 goto out;
163 }
164
165 if (ioctl(fd, HPET_INFO, &info) < 0) {
166 fprintf(stderr, "hpet_poll: failed to get info\n");
167 goto out;
168 }
169
170 fprintf(stderr, "hpet_poll: info.hi_flags 0x%lx\n", info.hi_flags);
171
172 if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
173 fprintf(stderr, "hpet_poll: HPET_EPI failed\n");
174 goto out;
175 }
176
177 if (ioctl(fd, HPET_IE_ON, 0) < 0) {
178 fprintf(stderr, "hpet_poll, HPET_IE_ON failed\n");
179 goto out;
180 }
181
182 pfd.fd = fd;
183 pfd.events = POLLIN;
184
185 for (i = 0; i < iterations; i++) {
186 pfd.revents = 0;
187 gettimeofday(&stv, &tz);
188 if (poll(&pfd, 1, -1) < 0)
189 fprintf(stderr, "hpet_poll: poll failed\n");
190 else {
191 long data;
192
193 gettimeofday(&etv, &tz);
194 usec = stv.tv_sec * 1000000 + stv.tv_usec;
195 usec = (etv.tv_sec * 1000000 + etv.tv_usec) - usec;
196
197 fprintf(stderr,
198 "hpet_poll: expired time = 0x%lx\n", usec);
199
200 fprintf(stderr, "hpet_poll: revents = 0x%x\n",
201 pfd.revents);
202
203 if (read(fd, &data, sizeof(data)) != sizeof(data)) {
204 fprintf(stderr, "hpet_poll: read failed\n");
205 }
206 else
207 fprintf(stderr, "hpet_poll: data 0x%lx\n",
208 data);
209 }
210 }
211
212out:
213 close(fd);
214 return;
215}
216
217static int hpet_sigio_count;
218
219static void
220hpet_sigio(int val)
221{
222 fprintf(stderr, "hpet_sigio: called\n");
223 hpet_sigio_count++;
224}
225
226void
227hpet_fasync(int argc, const char **argv)
228{
229 unsigned long freq;
230 int iterations, i, fd, value;
231 sig_t oldsig;
232 struct hpet_info info;
233
234 hpet_sigio_count = 0;
235 fd = -1;
236
237 if ((oldsig = signal(SIGIO, hpet_sigio)) == SIG_ERR) {
238 fprintf(stderr, "hpet_fasync: failed to set signal handler\n");
239 return;
240 }
241
242 if (argc != 3) {
243 fprintf(stderr, "hpet_fasync: device-name freq iterations\n");
244 goto out;
245 }
246
247 fd = open(argv[0], O_RDONLY);
248
249 if (fd < 0) {
250 fprintf(stderr, "hpet_fasync: failed to open %s\n", argv[0]);
251 return;
252 }
253
254
255 if ((fcntl(fd, F_SETOWN, getpid()) == 1) ||
256 ((value = fcntl(fd, F_GETFL)) == 1) ||
257 (fcntl(fd, F_SETFL, value | O_ASYNC) == 1)) {
258 fprintf(stderr, "hpet_fasync: fcntl failed\n");
259 goto out;
260 }
261
262 freq = atoi(argv[1]);
263 iterations = atoi(argv[2]);
264
265 if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
266 fprintf(stderr, "hpet_fasync: HPET_IRQFREQ failed\n");
267 goto out;
268 }
269
270 if (ioctl(fd, HPET_INFO, &info) < 0) {
271 fprintf(stderr, "hpet_fasync: failed to get info\n");
272 goto out;
273 }
274
275 fprintf(stderr, "hpet_fasync: info.hi_flags 0x%lx\n", info.hi_flags);
276
277 if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
278 fprintf(stderr, "hpet_fasync: HPET_EPI failed\n");
279 goto out;
280 }
281
282 if (ioctl(fd, HPET_IE_ON, 0) < 0) {
283 fprintf(stderr, "hpet_fasync, HPET_IE_ON failed\n");
284 goto out;
285 }
286
287 for (i = 0; i < iterations; i++) {
288 (void) pause();
289 fprintf(stderr, "hpet_fasync: count = %d\n", hpet_sigio_count);
290 }
291
292out:
293 signal(SIGIO, oldsig);
294
295 if (fd >= 0)
296 close(fd);
297
298 return;
299}
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