V4L/DVB (6668): Fix theoretical races between IRQ handler and .suspend/resume
*dev->insuspend = 1 should be set before synchronize_irq
*ACK interrupts after synchronize_irq, to make sure there aren't
pending interrupts.
*Add barrier before we restart interrupts so the handler will 100%
see the dev->insuspend
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/saa7134/saa7134-core.c b/drivers/media/video/saa7134/saa7134-core.c
index 40cdec2..85c165d 100644
--- a/drivers/media/video/saa7134/saa7134-core.c
+++ b/drivers/media/video/saa7134/saa7134-core.c
@@ -1181,8 +1181,13 @@
saa_writel(SAA7134_IRQ2, 0);
saa_writel(SAA7134_MAIN_CTRL, 0);
- synchronize_irq(pci_dev->irq);
dev->insuspend = 1;
+ synchronize_irq(pci_dev->irq);
+
+ /* ACK interrupts once more, just in case,
+ since the IRQ handler won't ack them anymore*/
+
+ saa_writel(SAA7134_IRQ_REPORT, saa_readl(SAA7134_IRQ_REPORT));
/* Disable timeout timers - if we have active buffers, we will
fill them on resume*/
@@ -1246,6 +1251,7 @@
/* start DMA now*/
dev->insuspend = 0;
+ smp_wmb();
saa7134_set_dmabits(dev);
spin_unlock_irqrestore(&dev->slock, flags);