staging: comedi: cleanup sysfs functions

Make the comedi sysfs functions a bit more concise by shortening
some of the verbose variable names and reusing some of the
variables that were used for intermediate calculations.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index 7677657..b3b86d4 100644 (file)
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -172,28 +172,19 @@ static int resize_async_buffer(struct comedi_device *dev,
 
 /* sysfs attribute files */
 
-static const unsigned bytes_per_kibi = 1024;
-
 static ssize_t show_max_read_buffer_kb(struct device *dev,
                                       struct device_attribute *attr, char *buf)
 {
-       ssize_t retval;
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned max_buffer_size_kb = 0;
-       struct comedi_subdevice *const read_subdevice =
-           comedi_get_read_subdevice(info);
+       struct comedi_subdevice *s = comedi_get_read_subdevice(info);
+       unsigned int size = 0;
 
        mutex_lock(&info->device->mutex);
-       if (read_subdevice &&
-           (read_subdevice->subdev_flags & SDF_CMD_READ) &&
-           read_subdevice->async) {
-               max_buffer_size_kb = read_subdevice->async->max_bufsize /
-                   bytes_per_kibi;
-       }
-       retval = snprintf(buf, PAGE_SIZE, "%i\n", max_buffer_size_kb);
+       if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
+               size = s->async->max_bufsize / 1024;
        mutex_unlock(&info->device->mutex);
 
-       return retval;
+       return snprintf(buf, PAGE_SIZE, "%i\n", size);
 }
 
 static ssize_t store_max_read_buffer_kb(struct device *dev,
@@ -201,52 +192,40 @@ static ssize_t store_max_read_buffer_kb(struct device *dev,
                                        const char *buf, size_t count)
 {
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned int new_max_size_kb;
-       unsigned int new_max_size;
-       int ret;
-       struct comedi_subdevice *const read_subdevice =
-           comedi_get_read_subdevice(info);
-
-       ret = kstrtouint(buf, 10, &new_max_size_kb);
-       if (ret)
-               return ret;
-       if (new_max_size_kb > (UINT_MAX / bytes_per_kibi))
+       struct comedi_subdevice *s = comedi_get_read_subdevice(info);
+       unsigned int size;
+       int err;
+
+       err = kstrtouint(buf, 10, &size);
+       if (err)
+               return err;
+       if (size > (UINT_MAX / 1024))
                return -EINVAL;
-       new_max_size = new_max_size_kb * bytes_per_kibi;
+       size *= 1024;
 
        mutex_lock(&info->device->mutex);
-       if (read_subdevice == NULL ||
-           (read_subdevice->subdev_flags & SDF_CMD_READ) == 0 ||
-           read_subdevice->async == NULL) {
-               mutex_unlock(&info->device->mutex);
-               return -EINVAL;
-       }
-       read_subdevice->async->max_bufsize = new_max_size;
+       if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
+               s->async->max_bufsize = size;
+       else
+               err = -EINVAL;
        mutex_unlock(&info->device->mutex);
 
-       return count;
+       return err ? err : count;
 }
 
 static ssize_t show_read_buffer_kb(struct device *dev,
                                   struct device_attribute *attr, char *buf)
 {
-       ssize_t retval;
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned buffer_size_kb = 0;
-       struct comedi_subdevice *const read_subdevice =
-           comedi_get_read_subdevice(info);
+       struct comedi_subdevice *s = comedi_get_read_subdevice(info);
+       unsigned int size = 0;
 
        mutex_lock(&info->device->mutex);
-       if (read_subdevice &&
-           (read_subdevice->subdev_flags & SDF_CMD_READ) &&
-           read_subdevice->async) {
-               buffer_size_kb = read_subdevice->async->prealloc_bufsz /
-                   bytes_per_kibi;
-       }
-       retval = snprintf(buf, PAGE_SIZE, "%i\n", buffer_size_kb);
+       if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
+               size = s->async->prealloc_bufsz / 1024;
        mutex_unlock(&info->device->mutex);
 
-       return retval;
+       return snprintf(buf, PAGE_SIZE, "%i\n", size);
 }
 
 static ssize_t store_read_buffer_kb(struct device *dev,
@@ -254,57 +233,41 @@ static ssize_t store_read_buffer_kb(struct device *dev,
                                    const char *buf, size_t count)
 {
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned int new_size_kb;
-       unsigned int new_size;
-       int retval;
-       int ret;
-       struct comedi_subdevice *const read_subdevice =
-           comedi_get_read_subdevice(info);
-
-       ret = kstrtouint(buf, 10, &new_size_kb);
-       if (ret)
-               return ret;
-       if (new_size_kb > (UINT_MAX / bytes_per_kibi))
+       struct comedi_subdevice *s = comedi_get_read_subdevice(info);
+       unsigned int size;
+       int err;
+
+       err = kstrtouint(buf, 10, &size);
+       if (err)
+               return err;
+       if (size > (UINT_MAX / 1024))
                return -EINVAL;
-       new_size = new_size_kb * bytes_per_kibi;
+       size *= 1024;
 
        mutex_lock(&info->device->mutex);
-       if (read_subdevice == NULL ||
-           (read_subdevice->subdev_flags & SDF_CMD_READ) == 0 ||
-           read_subdevice->async == NULL) {
-               mutex_unlock(&info->device->mutex);
-               return -EINVAL;
-       }
-       retval = resize_async_buffer(info->device, read_subdevice,
-                                    read_subdevice->async, new_size);
+       if (s && (s->subdev_flags & SDF_CMD_READ) && s->async)
+               err = resize_async_buffer(info->device, s, s->async, size);
+       else
+               err = -EINVAL;
        mutex_unlock(&info->device->mutex);
 
-       if (retval < 0)
-               return retval;
-       return count;
+       return err ? err : count;
 }
 
 static ssize_t show_max_write_buffer_kb(struct device *dev,
                                        struct device_attribute *attr,
                                        char *buf)
 {
-       ssize_t retval;
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned max_buffer_size_kb = 0;
-       struct comedi_subdevice *const write_subdevice =
-           comedi_get_write_subdevice(info);
+       struct comedi_subdevice *s = comedi_get_write_subdevice(info);
+       unsigned int size = 0;
 
        mutex_lock(&info->device->mutex);
-       if (write_subdevice &&
-           (write_subdevice->subdev_flags & SDF_CMD_WRITE) &&
-           write_subdevice->async) {
-               max_buffer_size_kb = write_subdevice->async->max_bufsize /
-                   bytes_per_kibi;
-       }
-       retval = snprintf(buf, PAGE_SIZE, "%i\n", max_buffer_size_kb);
+       if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
+               size = s->async->max_bufsize / 1024;
        mutex_unlock(&info->device->mutex);
 
-       return retval;
+       return snprintf(buf, PAGE_SIZE, "%i\n", size);
 }
 
 static ssize_t store_max_write_buffer_kb(struct device *dev,
@@ -312,52 +275,40 @@ static ssize_t store_max_write_buffer_kb(struct device *dev,
                                         const char *buf, size_t count)
 {
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned int new_max_size_kb;
-       unsigned int new_max_size;
-       int ret;
-       struct comedi_subdevice *const write_subdevice =
-           comedi_get_write_subdevice(info);
-
-       ret = kstrtouint(buf, 10, &new_max_size_kb);
-       if (ret)
-               return ret;
-       if (new_max_size_kb > (UINT_MAX / bytes_per_kibi))
+       struct comedi_subdevice *s = comedi_get_write_subdevice(info);
+       unsigned int size;
+       int err;
+
+       err = kstrtouint(buf, 10, &size);
+       if (err)
+               return err;
+       if (size > (UINT_MAX / 1024))
                return -EINVAL;
-       new_max_size = new_max_size_kb * bytes_per_kibi;
+       size *= 1024;
 
        mutex_lock(&info->device->mutex);
-       if (write_subdevice == NULL ||
-           (write_subdevice->subdev_flags & SDF_CMD_WRITE) == 0 ||
-           write_subdevice->async == NULL) {
-               mutex_unlock(&info->device->mutex);
-               return -EINVAL;
-       }
-       write_subdevice->async->max_bufsize = new_max_size;
+       if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
+               s->async->max_bufsize = size;
+       else
+               err = -EINVAL;
        mutex_unlock(&info->device->mutex);
 
-       return count;
+       return err ? err : count;
 }
 
 static ssize_t show_write_buffer_kb(struct device *dev,
                                    struct device_attribute *attr, char *buf)
 {
-       ssize_t retval;
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned buffer_size_kb = 0;
-       struct comedi_subdevice *const write_subdevice =
-           comedi_get_write_subdevice(info);
+       struct comedi_subdevice *s = comedi_get_write_subdevice(info);
+       unsigned int size = 0;
 
        mutex_lock(&info->device->mutex);
-       if (write_subdevice &&
-           (write_subdevice->subdev_flags & SDF_CMD_WRITE) &&
-           write_subdevice->async) {
-               buffer_size_kb = write_subdevice->async->prealloc_bufsz /
-                   bytes_per_kibi;
-       }
-       retval = snprintf(buf, PAGE_SIZE, "%i\n", buffer_size_kb);
+       if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
+               size = s->async->prealloc_bufsz / 1024;
        mutex_unlock(&info->device->mutex);
 
-       return retval;
+       return snprintf(buf, PAGE_SIZE, "%i\n", size);
 }
 
 static ssize_t store_write_buffer_kb(struct device *dev,
@@ -365,34 +316,25 @@ static ssize_t store_write_buffer_kb(struct device *dev,
                                     const char *buf, size_t count)
 {
        struct comedi_device_file_info *info = dev_get_drvdata(dev);
-       unsigned int new_size_kb;
-       unsigned int new_size;
-       int retval;
-       int ret;
-       struct comedi_subdevice *const write_subdevice =
-           comedi_get_write_subdevice(info);
-
-       ret = kstrtouint(buf, 10, &new_size_kb);
-       if (ret)
-               return ret;
-       if (new_size_kb > (UINT_MAX / bytes_per_kibi))
+       struct comedi_subdevice *s = comedi_get_write_subdevice(info);
+       unsigned int size;
+       int err;
+
+       err = kstrtouint(buf, 10, &size);
+       if (err)
+               return err;
+       if (size > (UINT_MAX / 1024))
                return -EINVAL;
-       new_size = ((uint64_t) new_size_kb) * bytes_per_kibi;
+       size *= 1024;
 
        mutex_lock(&info->device->mutex);
-       if (write_subdevice == NULL ||
-           (write_subdevice->subdev_flags & SDF_CMD_WRITE) == 0 ||
-           write_subdevice->async == NULL) {
-               mutex_unlock(&info->device->mutex);
-               return -EINVAL;
-       }
-       retval = resize_async_buffer(info->device, write_subdevice,
-                                    write_subdevice->async, new_size);
+       if (s && (s->subdev_flags & SDF_CMD_WRITE) && s->async)
+               err = resize_async_buffer(info->device, s, s->async, size);
+       else
+               err = -EINVAL;
        mutex_unlock(&info->device->mutex);
 
-       if (retval < 0)
-               return retval;
-       return count;
+       return err ? err : count;
 }
 
 static struct device_attribute comedi_dev_attrs[] = {