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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:04 EST.

1	#include <stdio.h>
2	#include <stdlib.h>
3	#include <unistd.h>
4	#include <fcntl.h>
5	#include <string.h>
6	#include <memory.h>
7	#include <malloc.h>
8	#include <time.h>
9	#include <ctype.h>
10	#include <sys/types.h>
11	#include <sys/wait.h>
12	#include <signal.h>
13	#include <errno.h>
14	#include <sys/time.h>
15	#include <linux/hpet.h>
16	
17	
18	extern void hpet_open_close(int, const char **);
19	extern void hpet_info(int, const char **);
20	extern void hpet_poll(int, const char **);
21	extern void hpet_fasync(int, const char **);
22	extern void hpet_read(int, const char **);
23	
24	#include <sys/poll.h>
25	#include <sys/ioctl.h>
26	
27	struct hpet_command {
28		char		*command;
29		void		(*func)(int argc, const char ** argv);
30	} hpet_command[] = {
31		{
32			"open-close",
33			hpet_open_close
34		},
35		{
36			"info",
37			hpet_info
38		},
39		{
40			"poll",
41			hpet_poll
42		},
43		{
44			"fasync",
45			hpet_fasync
46		},
47	};
48	
49	int
50	main(int argc, const char ** argv)
51	{
52		int	i;
53	
54		argc--;
55		argv++;
56	
57		if (!argc) {
58			fprintf(stderr, "-hpet: requires command\n");
59			return -1;
60		}
61	
62	
63		for (i = 0; i < (sizeof (hpet_command) / sizeof (hpet_command[0])); i++)
64			if (!strcmp(argv[0], hpet_command[i].command)) {
65				argc--;
66				argv++;
67				fprintf(stderr, "-hpet: executing %s\n",
68					hpet_command[i].command);
69				hpet_command[i].func(argc, argv);
70				return 0;
71			}
72	
73		fprintf(stderr, "do_hpet: command %s not implemented\n", argv[0]);
74	
75		return -1;
76	}
77	
78	void
79	hpet_open_close(int argc, const char **argv)
80	{
81		int	fd;
82	
83		if (argc != 1) {
84			fprintf(stderr, "hpet_open_close: device-name\n");
85			return;
86		}
87	
88		fd = open(argv[0], O_RDONLY);
89		if (fd < 0)
90			fprintf(stderr, "hpet_open_close: open failed\n");
91		else
92			close(fd);
93	
94		return;
95	}
96	
97	void
98	hpet_info(int argc, const char **argv)
99	{
100		struct hpet_info	info;
101		int			fd;
102	
103		if (argc != 1) {
104			fprintf(stderr, "hpet_info: device-name\n");
105			return;
106		}
107	
108		fd = open(argv[0], O_RDONLY);
109		if (fd < 0) {
110			fprintf(stderr, "hpet_info: open of %s failed\n", argv[0]);
111			return;
112		}
113	
114		if (ioctl(fd, HPET_INFO, &info) < 0) {
115			fprintf(stderr, "hpet_info: failed to get info\n");
116			goto out;
117		}
118	
119		fprintf(stderr, "hpet_info: hi_irqfreq 0x%lx hi_flags 0x%lx ",
120			info.hi_ireqfreq, info.hi_flags);
121		fprintf(stderr, "hi_hpet %d hi_timer %d\n",
122			info.hi_hpet, info.hi_timer);
123	
124	out:
125		close(fd);
126		return;
127	}
128	
129	void
130	hpet_poll(int argc, const char **argv)
131	{
132		unsigned long		freq;
133		int			iterations, i, fd;
134		struct pollfd		pfd;
135		struct hpet_info	info;
136		struct timeval		stv, etv;
137		struct timezone		tz;
138		long			usec;
139	
140		if (argc != 3) {
141			fprintf(stderr, "hpet_poll: device-name freq iterations\n");
142			return;
143		}
144	
145		freq = atoi(argv[1]);
146		iterations = atoi(argv[2]);
147	
148		fd = open(argv[0], O_RDONLY);
149	
150		if (fd < 0) {
151			fprintf(stderr, "hpet_poll: open of %s failed\n", argv[0]);
152			return;
153		}
154	
155		if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
156			fprintf(stderr, "hpet_poll: HPET_IRQFREQ failed\n");
157			goto out;
158		}
159	
160		if (ioctl(fd, HPET_INFO, &info) < 0) {
161			fprintf(stderr, "hpet_poll: failed to get info\n");
162			goto out;
163		}
164	
165		fprintf(stderr, "hpet_poll: info.hi_flags 0x%lx\n", info.hi_flags);
166	
167		if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
168			fprintf(stderr, "hpet_poll: HPET_EPI failed\n");
169			goto out;
170		}
171	
172		if (ioctl(fd, HPET_IE_ON, 0) < 0) {
173			fprintf(stderr, "hpet_poll, HPET_IE_ON failed\n");
174			goto out;
175		}
176	
177		pfd.fd = fd;
178		pfd.events = POLLIN;
179	
180		for (i = 0; i < iterations; i++) {
181			pfd.revents = 0;
182			gettimeofday(&stv, &tz);
183			if (poll(&pfd, 1, -1) < 0)
184				fprintf(stderr, "hpet_poll: poll failed\n");
185			else {
186				long 	data;
187	
188				gettimeofday(&etv, &tz);
189				usec = stv.tv_sec * 1000000 + stv.tv_usec;
190				usec = (etv.tv_sec * 1000000 + etv.tv_usec) - usec;
191	
192				fprintf(stderr,
193					"hpet_poll: expired time = 0x%lx\n", usec);
194	
195				fprintf(stderr, "hpet_poll: revents = 0x%x\n",
196					pfd.revents);
197	
198				if (read(fd, &data, sizeof(data)) != sizeof(data)) {
199					fprintf(stderr, "hpet_poll: read failed\n");
200				}
201				else
202					fprintf(stderr, "hpet_poll: data 0x%lx\n",
203						data);
204			}
205		}
206	
207	out:
208		close(fd);
209		return;
210	}
211	
212	static int hpet_sigio_count;
213	
214	static void
215	hpet_sigio(int val)
216	{
217		fprintf(stderr, "hpet_sigio: called\n");
218		hpet_sigio_count++;
219	}
220	
221	void
222	hpet_fasync(int argc, const char **argv)
223	{
224		unsigned long		freq;
225		int			iterations, i, fd, value;
226		sig_t			oldsig;
227		struct hpet_info	info;
228	
229		hpet_sigio_count = 0;
230		fd = -1;
231	
232		if ((oldsig = signal(SIGIO, hpet_sigio)) == SIG_ERR) {
233			fprintf(stderr, "hpet_fasync: failed to set signal handler\n");
234			return;
235		}
236	
237		if (argc != 3) {
238			fprintf(stderr, "hpet_fasync: device-name freq iterations\n");
239			goto out;
240		}
241	
242		fd = open(argv[0], O_RDONLY);
243	
244		if (fd < 0) {
245			fprintf(stderr, "hpet_fasync: failed to open %s\n", argv[0]);
246			return;
247		}
248	
249	
250		if ((fcntl(fd, F_SETOWN, getpid()) == 1) ||
251			((value = fcntl(fd, F_GETFL)) == 1) ||
252			(fcntl(fd, F_SETFL, value | O_ASYNC) == 1)) {
253			fprintf(stderr, "hpet_fasync: fcntl failed\n");
254			goto out;
255		}
256	
257		freq = atoi(argv[1]);
258		iterations = atoi(argv[2]);
259	
260		if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
261			fprintf(stderr, "hpet_fasync: HPET_IRQFREQ failed\n");
262			goto out;
263		}
264	
265		if (ioctl(fd, HPET_INFO, &info) < 0) {
266			fprintf(stderr, "hpet_fasync: failed to get info\n");
267			goto out;
268		}
269	
270		fprintf(stderr, "hpet_fasync: info.hi_flags 0x%lx\n", info.hi_flags);
271	
272		if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
273			fprintf(stderr, "hpet_fasync: HPET_EPI failed\n");
274			goto out;
275		}
276	
277		if (ioctl(fd, HPET_IE_ON, 0) < 0) {
278			fprintf(stderr, "hpet_fasync, HPET_IE_ON failed\n");
279			goto out;
280		}
281	
282		for (i = 0; i < iterations; i++) {
283			(void) pause();
284			fprintf(stderr, "hpet_fasync: count = %d\n", hpet_sigio_count);
285		}
286	
287	out:
288		signal(SIGIO, oldsig);
289	
290		if (fd >= 0)
291			close(fd);
292	
293		return;
294	}
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