[media] wl128x: remove V4L2_FL_LOCK_ALL_FOPS

Add proper locking to the file operations, allowing for the removal
of the V4L2_FL_LOCK_ALL_FOPS flag.

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

1 files changed, 26 insertions, 12 deletions

diff --git a/drivers/media/radio/wl128x/fmdrv_v4l2.c b/drivers/media/radio/wl128x/fmdrv_v4l2.c
index 49a11ec1f449..db2248ee9498 100644
--- a/drivers/media/radio/wl128x/fmdrv_v4l2.c
+++ b/drivers/media/radio/wl128x/fmdrv_v4l2.c
@@ -56,23 +56,29 @@ static ssize_t fm_v4l2_fops_read(struct file *file, char __user * buf,
                 return -EIO;
         }
 
-        /* Turn on RDS mode , if it is disabled */
+        if (mutex_lock_interruptible(&fmdev->mutex))
+                return -ERESTARTSYS;
+
+        /* Turn on RDS mode if it is disabled */
         ret = fm_rx_get_rds_mode(fmdev, &rds_mode);
         if (ret < 0) {
                 fmerr("Unable to read current rds mode\n");
-                return ret;
+                goto read_unlock;
         }
 
         if (rds_mode == FM_RDS_DISABLE) {
                 ret = fmc_set_rds_mode(fmdev, FM_RDS_ENABLE);
                 if (ret < 0) {
                         fmerr("Failed to enable rds mode\n");
-                        return ret;
+                        goto read_unlock;
                 }
         }
 
         /* Copy RDS data from internal buffer to user buffer */
-        return fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);
+        ret = fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);
+read_unlock:
+        mutex_unlock(&fmdev->mutex);
+        return ret;
 }
 
 /* Write TX RDS data */
@@ -91,8 +97,11 @@ static ssize_t fm_v4l2_fops_write(struct file *file, const char __user * buf,
                 return -EFAULT;
 
         fmdev = video_drvdata(file);
+        if (mutex_lock_interruptible(&fmdev->mutex))
+                return -ERESTARTSYS;
         fm_tx_set_radio_text(fmdev, rds.text, rds.text_type);
         fm_tx_set_af(fmdev, rds.af_freq);
+        mutex_unlock(&fmdev->mutex);
 
         return sizeof(rds);
 }
@@ -103,7 +112,9 @@ static u32 fm_v4l2_fops_poll(struct file *file, struct poll_table_struct *pts)
         struct fmdev *fmdev;
 
         fmdev = video_drvdata(file);
+        mutex_lock(&fmdev->mutex);
         ret = fmc_is_rds_data_available(fmdev, file, pts);
+        mutex_unlock(&fmdev->mutex);
         if (ret < 0)
                 return POLLIN | POLLRDNORM;
 
@@ -127,10 +138,12 @@ static int fm_v4l2_fops_open(struct file *file)
 
         fmdev = video_drvdata(file);
 
+        if (mutex_lock_interruptible(&fmdev->mutex))
+                return -ERESTARTSYS;
         ret = fmc_prepare(fmdev);
         if (ret < 0) {
                 fmerr("Unable to prepare FM CORE\n");
-                return ret;
+                goto open_unlock;
         }
 
         fmdbg("Load FM RX firmware..\n");
@@ -138,10 +151,12 @@ static int fm_v4l2_fops_open(struct file *file)
         ret = fmc_set_mode(fmdev, FM_MODE_RX);
         if (ret < 0) {
                 fmerr("Unable to load FM RX firmware\n");
-                return ret;
+                goto open_unlock;
         }
         radio_disconnected = 1;
 
+open_unlock:
+        mutex_unlock(&fmdev->mutex);
         return ret;
 }
 
@@ -156,19 +171,22 @@ static int fm_v4l2_fops_release(struct file *file)
                 return 0;
         }
 
+        mutex_lock(&fmdev->mutex);
         ret = fmc_set_mode(fmdev, FM_MODE_OFF);
         if (ret < 0) {
                 fmerr("Unable to turn off the chip\n");
-                return ret;
+                goto release_unlock;
         }
 
         ret = fmc_release(fmdev);
         if (ret < 0) {
                 fmerr("FM CORE release failed\n");
-                return ret;
+                goto release_unlock;
         }
         radio_disconnected = 0;
 
+release_unlock:
+        mutex_unlock(&fmdev->mutex);
         return ret;
 }
 
@@ -520,10 +538,6 @@ int fm_v4l2_init_video_device(struct fmdev *fmdev, int radio_nr)
         video_set_drvdata(gradio_dev, fmdev);
 
         gradio_dev->lock = &fmdev->mutex;
-        /* Locking in file operations other than ioctl should be done
-           by the driver, not the V4L2 core.
-           This driver needs auditing so that this flag can be removed. */
-        set_bit(V4L2_FL_LOCK_ALL_FOPS, &gradio_dev->flags);
 
         /* Register with V4L2 subsystem as RADIO device */
         if (video_register_device(gradio_dev, VFL_TYPE_RADIO, radio_nr)) {