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Diffstat (limited to 'drivers/media/radio/si470x/radio-si470x-common.c')
-rw-r--r--drivers/media/radio/si470x/radio-si470x-common.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/media/radio/si470x/radio-si470x-common.c b/drivers/media/radio/si470x/radio-si470x-common.c
index f33315f..4da0f15 100644
--- a/drivers/media/radio/si470x/radio-si470x-common.c
+++ b/drivers/media/radio/si470x/radio-si470x-common.c
@@ -426,6 +426,104 @@ int si470x_rds_on(struct si470x_device *radio)
/**************************************************************************
+ * File Operations Interface
+ **************************************************************************/
+
+/*
+ * si470x_fops_read - read RDS data
+ */
+static ssize_t si470x_fops_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct si470x_device *radio = video_drvdata(file);
+ int retval = 0;
+ unsigned int block_count = 0;
+
+ /* switch on rds reception */
+ if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
+ si470x_rds_on(radio);
+
+ /* block if no new data available */
+ while (radio->wr_index == radio->rd_index) {
+ if (file->f_flags & O_NONBLOCK) {
+ retval = -EWOULDBLOCK;
+ goto done;
+ }
+ if (wait_event_interruptible(radio->read_queue,
+ radio->wr_index != radio->rd_index) < 0) {
+ retval = -EINTR;
+ goto done;
+ }
+ }
+
+ /* calculate block count from byte count */
+ count /= 3;
+
+ /* copy RDS block out of internal buffer and to user buffer */
+ mutex_lock(&radio->lock);
+ while (block_count < count) {
+ if (radio->rd_index == radio->wr_index)
+ break;
+
+ /* always transfer rds complete blocks */
+ if (copy_to_user(buf, &radio->buffer[radio->rd_index], 3))
+ /* retval = -EFAULT; */
+ break;
+
+ /* increment and wrap read pointer */
+ radio->rd_index += 3;
+ if (radio->rd_index >= radio->buf_size)
+ radio->rd_index = 0;
+
+ /* increment counters */
+ block_count++;
+ buf += 3;
+ retval += 3;
+ }
+ mutex_unlock(&radio->lock);
+
+done:
+ return retval;
+}
+
+
+/*
+ * si470x_fops_poll - poll RDS data
+ */
+static unsigned int si470x_fops_poll(struct file *file,
+ struct poll_table_struct *pts)
+{
+ struct si470x_device *radio = video_drvdata(file);
+ int retval = 0;
+
+ /* switch on rds reception */
+ if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
+ si470x_rds_on(radio);
+
+ poll_wait(file, &radio->read_queue, pts);
+
+ if (radio->rd_index != radio->wr_index)
+ retval = POLLIN | POLLRDNORM;
+
+ return retval;
+}
+
+
+/*
+ * si470x_fops - file operations interface
+ */
+static const struct v4l2_file_operations si470x_fops = {
+ .owner = THIS_MODULE,
+ .read = si470x_fops_read,
+ .poll = si470x_fops_poll,
+ .ioctl = video_ioctl2,
+ .open = si470x_fops_open,
+ .release = si470x_fops_release,
+};
+
+
+
+/**************************************************************************
* Video4Linux Interface
**************************************************************************/