media: cx88-mpeg: clear interrupt status register before streaming video

[ Upstream commit 56cb61f70e547e1b0cdfe6ff5a1f1ce6242e6d96 ]

Some cx88 video cards may have transport stream status interrupts set
to 1 from cold start, causing errors like this:

  cx88xx: cx88_print_irqbits: core:irq mpeg  [0x100000] ts_err?*
  cx8802: cx8802_mpeg_irq: mpeg:general errors: 0x00100000

According to CX2388x datasheet, the interrupt status register should be
cleared before enabling IRQs to stream video.

Fix it by clearing the Transport Stream Interrupt Status register.

Signed-off-by: Daniel González Cabanelas <dgcbueu@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/media/pci/cx88/cx88-mpeg.c b/drivers/media/pci/cx88/cx88-mpeg.c
index 52ff00ebd4bda31b2971bdb110da18b878920150..281eca5253406c13dae9b5301412d037aba1cac4 100644 (file)
--- a/drivers/media/pci/cx88/cx88-mpeg.c
+++ b/drivers/media/pci/cx88/cx88-mpeg.c
@@ -171,6 +171,9 @@ int cx8802_start_dma(struct cx8802_dev    *dev,
        cx_write(MO_TS_GPCNTRL, GP_COUNT_CONTROL_RESET);
        q->count = 0;
 
+       /* clear interrupt status register */
+       cx_write(MO_TS_INTSTAT,  0x1f1111);
+
        /* enable irqs */
        dprintk(1, "setting the interrupt mask\n");
        cx_set(MO_PCI_INTMSK, core->pci_irqmask | PCI_INT_TSINT);