Documentation/timers/: split txt and source files

Documentation/timers/hpet.txt:
Expose example and tool source files in the Documentation/timers/ directory in
their own files instead of being buried (almost hidden) in readme/txt files.
This should help to prevent bitrot.

This will make them more visible/usable to users who may need
to use them, to developers who may need to test with them, and
to anyone who would fix/update them if they were more visible.

Also, if any of these possibly should not be in the kernel tree at
all, it will be clearer that they are here and we can discuss if
they should be removed.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 269 insertions, 0 deletions

diff --git a/Documentation/timers/hpet_example.c b/Documentation/timers/hpet_example.c
new file mode 100644
index 000000000000..f9ce2d9fdfd5
--- /dev/null
+++ b/Documentation/timers/hpet_example.c
@@ -0,0 +1,269 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <memory.h>
+#include <malloc.h>
+#include <time.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <linux/hpet.h>
+
+
+extern void hpet_open_close(int, const char **);
+extern void hpet_info(int, const char **);
+extern void hpet_poll(int, const char **);
+extern void hpet_fasync(int, const char **);
+extern void hpet_read(int, const char **);
+
+#include <sys/poll.h>
+#include <sys/ioctl.h>
+#include <signal.h>
+
+struct hpet_command {
+        char            *command;
+        void            (*func)(int argc, const char ** argv);
+} hpet_command[] = {
+        {
+                "open-close",
+                hpet_open_close
+        },
+        {
+                "info",
+                hpet_info
+        },
+        {
+                "poll",
+                hpet_poll
+        },
+        {
+                "fasync",
+                hpet_fasync
+        },
+};
+
+int
+main(int argc, const char ** argv)
+{
+        int     i;
+
+        argc--;
+        argv++;
+
+        if (!argc) {
+                fprintf(stderr, "-hpet: requires command\n");
+                return -1;
+        }
+
+
+        for (i = 0; i < (sizeof (hpet_command) / sizeof (hpet_command[0])); i++)
+                if (!strcmp(argv[0], hpet_command[i].command)) {
+                        argc--;
+                        argv++;
+                        fprintf(stderr, "-hpet: executing %s\n",
+                                hpet_command[i].command);
+                        hpet_command[i].func(argc, argv);
+                        return 0;
+                }
+
+        fprintf(stderr, "do_hpet: command %s not implemented\n", argv[0]);
+
+        return -1;
+}
+
+void
+hpet_open_close(int argc, const char **argv)
+{
+        int     fd;
+
+        if (argc != 1) {
+                fprintf(stderr, "hpet_open_close: device-name\n");
+                return;
+        }
+
+        fd = open(argv[0], O_RDONLY);
+        if (fd < 0)
+                fprintf(stderr, "hpet_open_close: open failed\n");
+        else
+                close(fd);
+
+        return;
+}
+
+void
+hpet_info(int argc, const char **argv)
+{
+}
+
+void
+hpet_poll(int argc, const char **argv)
+{
+        unsigned long           freq;
+        int                     iterations, i, fd;
+        struct pollfd           pfd;
+        struct hpet_info        info;
+        struct timeval          stv, etv;
+        struct timezone         tz;
+        long                    usec;
+
+        if (argc != 3) {
+                fprintf(stderr, "hpet_poll: device-name freq iterations\n");
+                return;
+        }
+
+        freq = atoi(argv[1]);
+        iterations = atoi(argv[2]);
+
+        fd = open(argv[0], O_RDONLY);
+
+        if (fd < 0) {
+                fprintf(stderr, "hpet_poll: open of %s failed\n", argv[0]);
+                return;
+        }
+
+        if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
+                fprintf(stderr, "hpet_poll: HPET_IRQFREQ failed\n");
+                goto out;
+        }
+
+        if (ioctl(fd, HPET_INFO, &info) < 0) {
+                fprintf(stderr, "hpet_poll: failed to get info\n");
+                goto out;
+        }
+
+        fprintf(stderr, "hpet_poll: info.hi_flags 0x%lx\n", info.hi_flags);
+
+        if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
+                fprintf(stderr, "hpet_poll: HPET_EPI failed\n");
+                goto out;
+        }
+
+        if (ioctl(fd, HPET_IE_ON, 0) < 0) {
+                fprintf(stderr, "hpet_poll, HPET_IE_ON failed\n");
+                goto out;
+        }
+
+        pfd.fd = fd;
+        pfd.events = POLLIN;
+
+        for (i = 0; i < iterations; i++) {
+                pfd.revents = 0;
+                gettimeofday(&stv, &tz);
+                if (poll(&pfd, 1, -1) < 0)
+                        fprintf(stderr, "hpet_poll: poll failed\n");
+                else {
+                        long    data;
+
+                        gettimeofday(&etv, &tz);
+                        usec = stv.tv_sec * 1000000 + stv.tv_usec;
+                        usec = (etv.tv_sec * 1000000 + etv.tv_usec) - usec;
+
+                        fprintf(stderr,
+                                "hpet_poll: expired time = 0x%lx\n", usec);
+
+                        fprintf(stderr, "hpet_poll: revents = 0x%x\n",
+                                pfd.revents);
+
+                        if (read(fd, &data, sizeof(data)) != sizeof(data)) {
+                                fprintf(stderr, "hpet_poll: read failed\n");
+                        }
+                        else
+                                fprintf(stderr, "hpet_poll: data 0x%lx\n",
+                                        data);
+                }
+        }
+
+out:
+        close(fd);
+        return;
+}
+
+static int hpet_sigio_count;
+
+static void
+hpet_sigio(int val)
+{
+        fprintf(stderr, "hpet_sigio: called\n");
+        hpet_sigio_count++;
+}
+
+void
+hpet_fasync(int argc, const char **argv)
+{
+        unsigned long           freq;
+        int                     iterations, i, fd, value;
+        sig_t                   oldsig;
+        struct hpet_info        info;
+
+        hpet_sigio_count = 0;
+        fd = -1;
+
+        if ((oldsig = signal(SIGIO, hpet_sigio)) == SIG_ERR) {
+                fprintf(stderr, "hpet_fasync: failed to set signal handler\n");
+                return;
+        }
+
+        if (argc != 3) {
+                fprintf(stderr, "hpet_fasync: device-name freq iterations\n");
+                goto out;
+        }
+
+        fd = open(argv[0], O_RDONLY);
+
+        if (fd < 0) {
+                fprintf(stderr, "hpet_fasync: failed to open %s\n", argv[0]);
+                return;
+        }
+
+
+        if ((fcntl(fd, F_SETOWN, getpid()) == 1) ||
+                ((value = fcntl(fd, F_GETFL)) == 1) ||
+                (fcntl(fd, F_SETFL, value | O_ASYNC) == 1)) {
+                fprintf(stderr, "hpet_fasync: fcntl failed\n");
+                goto out;
+        }
+
+        freq = atoi(argv[1]);
+        iterations = atoi(argv[2]);
+
+        if (ioctl(fd, HPET_IRQFREQ, freq) < 0) {
+                fprintf(stderr, "hpet_fasync: HPET_IRQFREQ failed\n");
+                goto out;
+        }
+
+        if (ioctl(fd, HPET_INFO, &info) < 0) {
+                fprintf(stderr, "hpet_fasync: failed to get info\n");
+                goto out;
+        }
+
+        fprintf(stderr, "hpet_fasync: info.hi_flags 0x%lx\n", info.hi_flags);
+
+        if (info.hi_flags && (ioctl(fd, HPET_EPI, 0) < 0)) {
+                fprintf(stderr, "hpet_fasync: HPET_EPI failed\n");
+                goto out;
+        }
+
+        if (ioctl(fd, HPET_IE_ON, 0) < 0) {
+                fprintf(stderr, "hpet_fasync, HPET_IE_ON failed\n");
+                goto out;
+        }
+
+        for (i = 0; i < iterations; i++) {
+                (void) pause();
+                fprintf(stderr, "hpet_fasync: count = %d\n", hpet_sigio_count);
+        }
+
+out:
+        signal(SIGIO, oldsig);
+
+        if (fd >= 0)
+                close(fd);
+
+        return;
+}