[media] radio-cadet: fix RDS handling

The current RDS code suffered from bit rot. Clean it up and make it work again.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/radio/radio-cadet.c b/drivers/media/radio/radio-cadet.c
index 93536b7e75c7770e975bf008090b6747117ddaf6..d1fb42746fc2a6c8eb0b125fb896948f2fd2bc6b 100644 (file)
--- a/drivers/media/radio/radio-cadet.c
+++ b/drivers/media/radio/radio-cadet.c
@@ -71,7 +71,7 @@ struct cadet {
        int sigstrength;
        wait_queue_head_t read_queue;
        struct timer_list readtimer;
-       __u8 rdsin, rdsout, rdsstat;
+       u8 rdsin, rdsout, rdsstat;
        unsigned char rdsbuf[RDS_BUFFER];
        struct mutex lock;
        int reading;
@@ -85,8 +85,8 @@ static struct cadet cadet_card;
  * strength value.  These values are in microvolts of RF at the tuner's input.
  */
 static __u16 sigtable[2][4] = {
-       {  5, 10, 30,  150 },
-       { 28, 40, 63, 1000 }
+       { 2185, 4369, 13107, 65535 },
+       { 1835, 2621,  4128, 65535 }
 };
 
 
@@ -240,10 +240,13 @@ static void cadet_setfreq(struct cadet *dev, unsigned freq)
                cadet_gettune(dev);
                if ((dev->tunestat & 0x40) == 0) {   /* Tuned */
                        dev->sigstrength = sigtable[dev->curtuner][j];
-                       return;
+                       goto reset_rds;
                }
        }
        dev->sigstrength = 0;
+reset_rds:
+       outb(3, dev->io);
+       outb(inb(dev->io + 1) & 0x7f, dev->io + 1);
 }
 
 
@@ -259,7 +262,7 @@ static void cadet_handler(unsigned long data)
                outb(0x80, dev->io);      /* Select RDS fifo */
                while ((inb(dev->io) & 0x80) != 0) {
                        dev->rdsbuf[dev->rdsin] = inb(dev->io + 1);
-                       if (dev->rdsin == dev->rdsout)
+                       if (dev->rdsin + 1 == dev->rdsout)
                                printk(KERN_WARNING "cadet: RDS buffer overflow\n");
                        else
                                dev->rdsin++;
@@ -278,11 +281,21 @@ static void cadet_handler(unsigned long data)
         */
        init_timer(&dev->readtimer);
        dev->readtimer.function = cadet_handler;
-       dev->readtimer.data = (unsigned long)0;
+       dev->readtimer.data = data;
        dev->readtimer.expires = jiffies + msecs_to_jiffies(50);
        add_timer(&dev->readtimer);
 }
 
+static void cadet_start_rds(struct cadet *dev)
+{
+       dev->rdsstat = 1;
+       outb(0x80, dev->io);        /* Select RDS fifo */
+       init_timer(&dev->readtimer);
+       dev->readtimer.function = cadet_handler;
+       dev->readtimer.data = (unsigned long)dev;
+       dev->readtimer.expires = jiffies + msecs_to_jiffies(50);
+       add_timer(&dev->readtimer);
+}
 
 static ssize_t cadet_read(struct file *file, char __user *data, size_t count, loff_t *ppos)
 {
@@ -291,26 +304,21 @@ static ssize_t cadet_read(struct file *file, char __user *data, size_t count, lo
        int i = 0;
 
        mutex_lock(&dev->lock);
-       if (dev->rdsstat == 0) {
-               dev->rdsstat = 1;
-               outb(0x80, dev->io);        /* Select RDS fifo */
-               init_timer(&dev->readtimer);
-               dev->readtimer.function = cadet_handler;
-               dev->readtimer.data = (unsigned long)dev;
-               dev->readtimer.expires = jiffies + msecs_to_jiffies(50);
-               add_timer(&dev->readtimer);
-       }
+       if (dev->rdsstat == 0)
+               cadet_start_rds(dev);
        if (dev->rdsin == dev->rdsout) {
                if (file->f_flags & O_NONBLOCK) {
                        i = -EWOULDBLOCK;
                        goto unlock;
                }
+               mutex_unlock(&dev->lock);
                interruptible_sleep_on(&dev->read_queue);
+               mutex_lock(&dev->lock);
        }
        while (i < count && dev->rdsin != dev->rdsout)
                readbuf[i++] = dev->rdsbuf[dev->rdsout++];
 
-       if (copy_to_user(data, readbuf, i))
+       if (i && copy_to_user(data, readbuf, i))
                i = -EFAULT;
 unlock:
        mutex_unlock(&dev->lock);
@@ -345,7 +353,12 @@ static int vidioc_g_tuner(struct file *file, void *priv,
                v->rangehigh = 1728000;    /* 108.0 MHz */
                v->rxsubchans = cadet_getstereo(dev);
                v->audmode = V4L2_TUNER_MODE_STEREO;
-               v->rxsubchans |= V4L2_TUNER_SUB_RDS;
+               outb(3, dev->io);
+               outb(inb(dev->io + 1) & 0x7f, dev->io + 1);
+               mdelay(100);
+               outb(3, dev->io);
+               if (inb(dev->io + 1) & 0x80)
+                       v->rxsubchans |= V4L2_TUNER_SUB_RDS;
                break;
        case 1:
                strlcpy(v->name, "AM", sizeof(v->name));
@@ -455,9 +468,16 @@ static int cadet_release(struct file *file)
 static unsigned int cadet_poll(struct file *file, struct poll_table_struct *wait)
 {
        struct cadet *dev = video_drvdata(file);
+       unsigned long req_events = poll_requested_events(wait);
        unsigned int res = v4l2_ctrl_poll(file, wait);
 
        poll_wait(file, &dev->read_queue, wait);
+       if (dev->rdsstat == 0 && (req_events & (POLLIN | POLLRDNORM))) {
+               mutex_lock(&dev->lock);
+               if (dev->rdsstat == 0)
+                       cadet_start_rds(dev);
+               mutex_unlock(&dev->lock);
+       }
        if (dev->rdsin != dev->rdsout)
                res |= POLLIN | POLLRDNORM;
        return res;
@@ -628,6 +648,8 @@ static void __exit cadet_exit(void)
        video_unregister_device(&dev->vdev);
        v4l2_ctrl_handler_free(&dev->ctrl_handler);
        v4l2_device_unregister(&dev->v4l2_dev);
+       outb(7, dev->io);       /* Mute */
+       outb(0x00, dev->io + 1);
        release_region(dev->io, 2);
        pnp_unregister_driver(&cadet_pnp_driver);
 }