[media] ivtv: fix sparse warning

Fix this warning:

drivers/media/pci/ivtv/ivtv-irq.c:418:9: warning: context imbalance in 'ivtv_dma_stream_dec_prepare' - different lock contexts for basic block

sparse didn't quite understand the locking scheme, so rewrite it to keep
sparse happy.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Andy Walls <awalls@md.metrocast.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/pci/ivtv/ivtv-irq.c b/drivers/media/pci/ivtv/ivtv-irq.c
index ab6d5d25aa6fdd1a757814c18318dc5881e47a41..e7d701777e53fe44af8426685c7aaf57996c90ab 100644 (file)
--- a/drivers/media/pci/ivtv/ivtv-irq.c
+++ b/drivers/media/pci/ivtv/ivtv-irq.c
@@ -357,7 +357,6 @@ void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock)
        u32 uv_offset = offset + IVTV_YUV_BUFFER_UV_OFFSET;
        int y_done = 0;
        int bytes_written = 0;
-       unsigned long flags = 0;
        int idx = 0;
 
        IVTV_DEBUG_HI_DMA("DEC PREPARE DMA %s: %08x %08x\n", s->name, s->q_predma.bytesused, offset);
@@ -407,16 +406,21 @@ void ivtv_dma_stream_dec_prepare(struct ivtv_stream *s, u32 offset, int lock)
 
        /* Sync Hardware SG List of buffers */
        ivtv_stream_sync_for_device(s);
-       if (lock)
+       if (lock) {
+               unsigned long flags = 0;
+
                spin_lock_irqsave(&itv->dma_reg_lock, flags);
-       if (!test_bit(IVTV_F_I_DMA, &itv->i_flags)) {
-               ivtv_dma_dec_start(s);
-       }
-       else {
-               set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
-       }
-       if (lock)
+               if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
+                       ivtv_dma_dec_start(s);
+               else
+                       set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
                spin_unlock_irqrestore(&itv->dma_reg_lock, flags);
+       } else {
+               if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
+                       ivtv_dma_dec_start(s);
+               else
+                       set_bit(IVTV_F_S_DMA_PENDING, &s->s_flags);
+       }
 }
 
 static void ivtv_dma_enc_start_xfer(struct ivtv_stream *s)