media: ipu3-cio2: Replace infinite loop by one with clear exit condition

Refactor cio2_buffer_done() to get rid of infinite loop by replacing it by
one with clear exit condition. This change also allows to check for an
error ahead.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
index a9a2572..025a3ba 100644 (file)
--- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
+++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
@@ -540,7 +540,7 @@ static void cio2_buffer_done(struct cio2_device *cio2, unsigned int dma_chan)
 {
        struct device *dev = &cio2->pci_dev->dev;
        struct cio2_queue *q = cio2->cur_queue;
-       int buffers_found = 0;
+       struct cio2_fbpt_entry *entry;
        u64 ns = ktime_get_ns();
 
        if (dma_chan >= CIO2_QUEUES) {
@@ -548,15 +548,18 @@ static void cio2_buffer_done(struct cio2_device *cio2, unsigned int dma_chan)
                return;
        }
 
+       entry = &q->fbpt[q->bufs_first * CIO2_MAX_LOPS];
+       if (entry->first_entry.ctrl & CIO2_FBPT_CTRL_VALID) {
+               dev_warn(&cio2->pci_dev->dev,
+                        "no ready buffers found on DMA channel %u\n",
+                        dma_chan);
+               return;
+       }
+
        /* Find out which buffer(s) are ready */
        do {
-               struct cio2_fbpt_entry *const entry =
-                       &q->fbpt[q->bufs_first * CIO2_MAX_LOPS];
                struct cio2_buffer *b;
 
-               if (entry->first_entry.ctrl & CIO2_FBPT_CTRL_VALID)
-                       break;
-
                b = q->bufs[q->bufs_first];
                if (b) {
                        unsigned int bytes = entry[1].second_entry.num_of_bytes;
@@ -578,13 +581,8 @@ static void cio2_buffer_done(struct cio2_device *cio2, unsigned int dma_chan)
                atomic_inc(&q->frame_sequence);
                cio2_fbpt_entry_init_dummy(cio2, entry);
                q->bufs_first = (q->bufs_first + 1) % CIO2_MAX_BUFFERS;
-               buffers_found++;
-       } while (1);
-
-       if (buffers_found == 0)
-               dev_warn(&cio2->pci_dev->dev,
-                        "no ready buffers found on DMA channel %u\n",
-                        dma_chan);
+               entry = &q->fbpt[q->bufs_first * CIO2_MAX_LOPS];
+       } while (!(entry->first_entry.ctrl & CIO2_FBPT_CTRL_VALID));
 }
 
 static void cio2_queue_event_sof(struct cio2_device *cio2, struct cio2_queue *q)