documentation: move spidev_fdx example to its own source file

Move sample source code to its own source file so that it can be used
easier and build-tested/check/maintained by anyone.

(Makefile changes are in a separate patch for all of Documentation/.)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 160 insertions, 166 deletions

diff --git a/Documentation/spi/spidev b/Documentation/spi/spidev
index 5c8e1b988a08..ed2da5e5b28a 100644
--- a/Documentation/spi/spidev
+++ b/Documentation/spi/spidev
@@ -126,8 +126,8 @@ NOTES:
 FULL DUPLEX CHARACTER DEVICE API
 ================================
 
-See the sample program below for one example showing the use of the full
-duplex programming interface.  (Although it doesn't perform a full duplex
+See the spidev_fdx.c sample program for one example showing the use of the
+full duplex programming interface.  (Although it doesn't perform a full duplex
 transfer.)  The model is the same as that used in the kernel spi_sync()
 request; the individual transfers offer the same capabilities as are
 available to kernel drivers (except that it's not asynchronous).
@@ -141,167 +141,3 @@ and bitrate for each transfer segment.)
 
 To make a full duplex request, provide both rx_buf and tx_buf for the
 same transfer.  It's even OK if those are the same buffer.
-
-
-SAMPLE PROGRAM
-==============
-
---------------------------------        CUT HERE
-#include <stdio.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <fcntl.h>
-#include <string.h>
-
-#include <sys/ioctl.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-
-#include <linux/types.h>
-#include <linux/spi/spidev.h>
-
-
-static int verbose;
-
-static void do_read(int fd, int len)
-{
-        unsigned char   buf[32], *bp;
-        int             status;
-
-        /* read at least 2 bytes, no more than 32 */
-        if (len < 2)
-                len = 2;
-        else if (len > sizeof(buf))
-                len = sizeof(buf);
-        memset(buf, 0, sizeof buf);
-
-        status = read(fd, buf, len);
-        if (status < 0) {
-                perror("read");
-                return;
-        }
-        if (status != len) {
-                fprintf(stderr, "short read\n");
-                return;
-        }
-
-        printf("read(%2d, %2d): %02x %02x,", len, status,
-                buf[0], buf[1]);
-        status -= 2;
-        bp = buf + 2;
-        while (status-- > 0)
-                printf(" %02x", *bp++);
-        printf("\n");
-}
-
-static void do_msg(int fd, int len)
-{
-        struct spi_ioc_transfer xfer[2];
-        unsigned char           buf[32], *bp;
-        int                     status;
-
-        memset(xfer, 0, sizeof xfer);
-        memset(buf, 0, sizeof buf);
-
-        if (len > sizeof buf)
-                len = sizeof buf;
-
-        buf[0] = 0xaa;
-        xfer[0].tx_buf = (__u64) buf;
-        xfer[0].len = 1;
-
-        xfer[1].rx_buf = (__u64) buf;
-        xfer[1].len = len;
-
-        status = ioctl(fd, SPI_IOC_MESSAGE(2), xfer);
-        if (status < 0) {
-                perror("SPI_IOC_MESSAGE");
-                return;
-        }
-
-        printf("response(%2d, %2d): ", len, status);
-        for (bp = buf; len; len--)
-                printf(" %02x", *bp++);
-        printf("\n");
-}
-
-static void dumpstat(const char *name, int fd)
-{
-        __u8    mode, lsb, bits;
-        __u32   speed;
-
-        if (ioctl(fd, SPI_IOC_RD_MODE, &mode) < 0) {
-                perror("SPI rd_mode");
-                return;
-        }
-        if (ioctl(fd, SPI_IOC_RD_LSB_FIRST, &lsb) < 0) {
-                perror("SPI rd_lsb_fist");
-                return;
-        }
-        if (ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits) < 0) {
-                perror("SPI bits_per_word");
-                return;
-        }
-        if (ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) < 0) {
-                perror("SPI max_speed_hz");
-                return;
-        }
-
-        printf("%s: spi mode %d, %d bits %sper word, %d Hz max\n",
-                name, mode, bits, lsb ? "(lsb first) " : "", speed);
-}
-
-int main(int argc, char **argv)
-{
-        int             c;
-        int             readcount = 0;
-        int             msglen = 0;
-        int             fd;
-        const char      *name;
-
-        while ((c = getopt(argc, argv, "hm:r:v")) != EOF) {
-                switch (c) {
-                case 'm':
-                        msglen = atoi(optarg);
-                        if (msglen < 0)
-                                goto usage;
-                        continue;
-                case 'r':
-                        readcount = atoi(optarg);
-                        if (readcount < 0)
-                                goto usage;
-                        continue;
-                case 'v':
-                        verbose++;
-                        continue;
-                case 'h':
-                case '?':
-usage:
-                        fprintf(stderr,
-                                "usage: %s [-h] [-m N] [-r N] /dev/spidevB.D\n",
-                                argv[0]);
-                        return 1;
-                }
-        }
-
-        if ((optind + 1) != argc)
-                goto usage;
-        name = argv[optind];
-
-        fd = open(name, O_RDWR);
-        if (fd < 0) {
-                perror("open");
-                return 1;
-        }
-
-        dumpstat(name, fd);
-
-        if (msglen)
-                do_msg(fd, msglen);
-
-        if (readcount)
-                do_read(fd, readcount);
-
-        close(fd);
-        return 0;
-}
diff --git a/Documentation/spi/spidev_fdx.c b/Documentation/spi/spidev_fdx.c
new file mode 100644
index 000000000000..fc354f760384
--- /dev/null
+++ b/Documentation/spi/spidev_fdx.c
@@ -0,0 +1,158 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <string.h>
+
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <linux/types.h>
+#include <linux/spi/spidev.h>
+
+
+static int verbose;
+
+static void do_read(int fd, int len)
+{
+        unsigned char   buf[32], *bp;
+        int             status;
+
+        /* read at least 2 bytes, no more than 32 */
+        if (len < 2)
+                len = 2;
+        else if (len > sizeof(buf))
+                len = sizeof(buf);
+        memset(buf, 0, sizeof buf);
+
+        status = read(fd, buf, len);
+        if (status < 0) {
+                perror("read");
+                return;
+        }
+        if (status != len) {
+                fprintf(stderr, "short read\n");
+                return;
+        }
+
+        printf("read(%2d, %2d): %02x %02x,", len, status,
+                buf[0], buf[1]);
+        status -= 2;
+        bp = buf + 2;
+        while (status-- > 0)
+                printf(" %02x", *bp++);
+        printf("\n");
+}
+
+static void do_msg(int fd, int len)
+{
+        struct spi_ioc_transfer xfer[2];
+        unsigned char           buf[32], *bp;
+        int                     status;
+
+        memset(xfer, 0, sizeof xfer);
+        memset(buf, 0, sizeof buf);
+
+        if (len > sizeof buf)
+                len = sizeof buf;
+
+        buf[0] = 0xaa;
+        xfer[0].tx_buf = (__u64) buf;
+        xfer[0].len = 1;
+
+        xfer[1].rx_buf = (__u64) buf;
+        xfer[1].len = len;
+
+        status = ioctl(fd, SPI_IOC_MESSAGE(2), xfer);
+        if (status < 0) {
+                perror("SPI_IOC_MESSAGE");
+                return;
+        }
+
+        printf("response(%2d, %2d): ", len, status);
+        for (bp = buf; len; len--)
+                printf(" %02x", *bp++);
+        printf("\n");
+}
+
+static void dumpstat(const char *name, int fd)
+{
+        __u8    mode, lsb, bits;
+        __u32   speed;
+
+        if (ioctl(fd, SPI_IOC_RD_MODE, &mode) < 0) {
+                perror("SPI rd_mode");
+                return;
+        }
+        if (ioctl(fd, SPI_IOC_RD_LSB_FIRST, &lsb) < 0) {
+                perror("SPI rd_lsb_fist");
+                return;
+        }
+        if (ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits) < 0) {
+                perror("SPI bits_per_word");
+                return;
+        }
+        if (ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) < 0) {
+                perror("SPI max_speed_hz");
+                return;
+        }
+
+        printf("%s: spi mode %d, %d bits %sper word, %d Hz max\n",
+                name, mode, bits, lsb ? "(lsb first) " : "", speed);
+}
+
+int main(int argc, char **argv)
+{
+        int             c;
+        int             readcount = 0;
+        int             msglen = 0;
+        int             fd;
+        const char      *name;
+
+        while ((c = getopt(argc, argv, "hm:r:v")) != EOF) {
+                switch (c) {
+                case 'm':
+                        msglen = atoi(optarg);
+                        if (msglen < 0)
+                                goto usage;
+                        continue;
+                case 'r':
+                        readcount = atoi(optarg);
+                        if (readcount < 0)
+                                goto usage;
+                        continue;
+                case 'v':
+                        verbose++;
+                        continue;
+                case 'h':
+                case '?':
+usage:
+                        fprintf(stderr,
+                                "usage: %s [-h] [-m N] [-r N] /dev/spidevB.D\n",
+                                argv[0]);
+                        return 1;
+                }
+        }
+
+        if ((optind + 1) != argc)
+                goto usage;
+        name = argv[optind];
+
+        fd = open(name, O_RDWR);
+        if (fd < 0) {
+                perror("open");
+                return 1;
+        }
+
+        dumpstat(name, fd);
+
+        if (msglen)
+                do_msg(fd, msglen);
+
+        if (readcount)
+                do_read(fd, readcount);
+
+        close(fd);
+        return 0;
+}