staging:iio:Documentation generic_buffer.c update to new abi for buffers + misc fixes

Trivial space before newline fix incorporated.

Additional fixes related to handling of sign extension and shifted
data.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
squash into buffer handling update.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/iio/Documentation/generic_buffer.c b/drivers/staging/iio/Documentation/generic_buffer.c
index eb72e95f76f847f87cb8aad47d6320050d786db5..f82894f42d27f96c196fc8d964d8fa7634360b96 100644 (file)
--- a/drivers/staging/iio/Documentation/generic_buffer.c
+++ b/drivers/staging/iio/Documentation/generic_buffer.c
@@ -27,6 +27,7 @@
 #include <sys/dir.h>
 #include <linux/types.h>
 #include <string.h>
+#include <poll.h>
 #include "iio_utils.h"
 
 /**
@@ -53,6 +54,24 @@ int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
        return bytes;
 }
 
+void print2byte(int input, struct iio_channel_info *info)
+{
+       /* shift before conversion to avoid sign extension
+          of left aligned data */
+       input = input >> info->shift;
+       if (info->is_signed) {
+               int16_t val = input;
+               val &= (1 << info->bits_used) - 1;
+               val = (int16_t)(val << (16 - info->bits_used)) >>
+                       (16 - info->bits_used);
+               printf("%05f  ", val,
+                      (float)(val + info->offset)*info->scale);
+       } else {
+               uint16_t val = input;
+               val &= (1 << info->bits_used) - 1;
+               printf("%05f ", ((float)val + info->offset)*info->scale);
+       }
+}
 /**
  * process_scan() - print out the values in SI units
  * @data:              pointer to the start of the scan
@@ -70,25 +89,8 @@ void process_scan(char *data,
                switch (infoarray[k].bytes) {
                        /* only a few cases implemented so far */
                case 2:
-                       if (infoarray[k].is_signed) {
-                               int16_t val = *(int16_t *)
-                                       (data
-                                        + infoarray[k].location);
-                               if ((val >> infoarray[k].bits_used) & 1)
-                                       val = (val & infoarray[k].mask) |
-                                               ~infoarray[k].mask;
-                               printf("%05f ", ((float)val +
-                                                infoarray[k].offset)*
-                                      infoarray[k].scale);
-                       } else {
-                               uint16_t val = *(uint16_t *)
-                                       (data +
-                                        infoarray[k].location);
-                               val = (val & infoarray[k].mask);
-                               printf("%05f ", ((float)val +
-                                                infoarray[k].offset)*
-                                      infoarray[k].scale);
-                       }
+                       print2byte(*(uint16_t *)(data + infoarray[k].location),
+                                  &infoarray[k]);
                        break;
                case 8:
                        if (infoarray[k].is_signed) {
@@ -133,9 +135,8 @@ int main(int argc, char **argv)
        int datardytrigger = 1;
        char *data;
        ssize_t read_size;
-       struct iio_event_data dat;
        int dev_num, trig_num;
-       char *buffer_access, *buffer_event;
+       char *buffer_access;
        int scan_size;
        int noevents = 0;
        char *dummy;
@@ -210,7 +211,7 @@ int main(int argc, char **argv)
         */
        ret = build_channel_array(dev_dir_name, &infoarray, &num_channels);
        if (ret) {
-               printf("Problem reading scan element information \n");
+               printf("Problem reading scan element information\n");
                goto error_free_triggername;
        }
 
@@ -251,54 +252,32 @@ int main(int argc, char **argv)
        }
 
        ret = asprintf(&buffer_access,
-                      "/dev/device%d:buffer0:access0",
+                      "/dev/device%d:buffer0",
                       dev_num);
        if (ret < 0) {
                ret = -ENOMEM;
                goto error_free_data;
        }
 
-       ret = asprintf(&buffer_event, "/dev/device%d:buffer0:event0", dev_num);
-       if (ret < 0) {
-               ret = -ENOMEM;
-               goto error_free_buffer_access;
-       }
        /* Attempt to open non blocking the access dev */
        fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
        if (fp == -1) { /*If it isn't there make the node */
                printf("Failed to open %s\n", buffer_access);
                ret = -errno;
-               goto error_free_buffer_event;
-       }
-       /* Attempt to open the event access dev (blocking this time) */
-       fp_ev = fopen(buffer_event, "rb");
-       if (fp_ev == NULL) {
-               printf("Failed to open %s\n", buffer_event);
-               ret = -errno;
-               goto error_close_buffer_access;
+               goto error_free_buffer_access;
        }
 
        /* Wait for events 10 times */
        for (j = 0; j < num_loops; j++) {
                if (!noevents) {
-                       read_size = fread(&dat,
-                                       1,
-                                       sizeof(struct iio_event_data),
-                                       fp_ev);
-                       switch (dat.id) {
-                       case IIO_EVENT_CODE_RING_100_FULL:
-                               toread = buf_len;
-                               break;
-                       case IIO_EVENT_CODE_RING_75_FULL:
-                               toread = buf_len*3/4;
-                               break;
-                       case IIO_EVENT_CODE_RING_50_FULL:
-                               toread = buf_len/2;
-                               break;
-                       default:
-                               printf("Unexpecteded event code\n");
-                               continue;
-                       }
+                       struct pollfd pfd = {
+                               .fd = fp,
+                               .events = POLLIN,
+                       };
+
+                       poll(&pfd, 1, -1);
+                       toread = buf_len;
+
                } else {
                        usleep(timedelay);
                        toread = 64;
@@ -320,22 +299,18 @@ int main(int argc, char **argv)
        /* Stop the ring buffer */
        ret = write_sysfs_int("enable", buf_dir_name, 0);
        if (ret < 0)
-               goto error_close_buffer_event;
+               goto error_close_buffer_access;
 
        /* Disconnect from the trigger - just write a dummy name.*/
        write_sysfs_string("trigger/current_trigger",
                        dev_dir_name, "NULL");
 
-error_close_buffer_event:
-       fclose(fp_ev);
 error_close_buffer_access:
        close(fp);
 error_free_data:
        free(data);
 error_free_buffer_access:
        free(buffer_access);
-error_free_buffer_event:
-       free(buffer_event);
 error_free_buf_dir_name:
        free(buf_dir_name);
 error_free_triggername:

diff --git a/drivers/staging/iio/Documentation/iio_utils.h b/drivers/staging/iio/Documentation/iio_utils.h
index fd78e4ff99ae36abcc6fd476441304eba45b528d..150f44073631314b49628ca9cc21532bee70d8ee 100644 (file)
--- a/drivers/staging/iio/Documentation/iio_utils.h
+++ b/drivers/staging/iio/Documentation/iio_utils.h
@@ -16,25 +16,11 @@
 
 #define IIO_MAX_NAME_LENGTH 30
 
-#define IIO_EV_CLASS_BUFFER            0
-#define IIO_BUFFER_EVENT_CODE(code)            \
-       (IIO_EV_CLASS_BUFFER | (code << 8))
-
-#define IIO_EVENT_CODE_RING_50_FULL    IIO_BUFFER_EVENT_CODE(0)
-#define IIO_EVENT_CODE_RING_75_FULL    IIO_BUFFER_EVENT_CODE(1)
-#define IIO_EVENT_CODE_RING_100_FULL   IIO_BUFFER_EVENT_CODE(2)
-
-
 #define FORMAT_SCAN_ELEMENTS_DIR "%s:buffer0/scan_elements"
 #define FORMAT_TYPE_FILE "%s_type"
 
 const char *iio_dir = "/sys/bus/iio/devices/";
 
-struct iio_event_data {
-       int id;
-       __s64 timestamp;
-};
-
 /**
  * iioutils_break_up_name() - extract generic name from full channel name
  * @full_name: the full channel name
@@ -85,6 +71,7 @@ struct iio_channel_info {
        unsigned index;
        unsigned bytes;
        unsigned bits_used;
+       unsigned shift;
        uint64_t mask;
        unsigned is_signed;
        unsigned enabled;
@@ -103,6 +90,7 @@ struct iio_channel_info {
 inline int iioutils_get_type(unsigned *is_signed,
                             unsigned *bytes,
                             unsigned *bits_used,
+                            unsigned *shift,
                             uint64_t *mask,
                             const char *device_dir,
                             const char *name,
@@ -157,7 +145,8 @@ inline int iioutils_get_type(unsigned *is_signed,
                                goto error_free_filename;
                        }
                        fscanf(sysfsfp,
-                              "%c%u/%u", &signchar, bits_used, &padint);
+                              "%c%u/%u>>%u", &signchar, bits_used,
+                              &padint, shift);
                        *bytes = padint / 8;
                        if (*bits_used == 64)
                                *mask = ~0;
@@ -395,6 +384,7 @@ inline int build_channel_array(const char *device_dir,
                        ret = iioutils_get_type(&current->is_signed,
                                                &current->bytes,
                                                &current->bits_used,
+                                               &current->shift,
                                                &current->mask,
                                                device_dir,
                                                current->name,