[PATCH AUTOSEL 5.10 25/37] media: cx88-mpeg: clear interrupt status register before streaming video

Sasha Levin
2022-03-30T12:14:58Z

From: Daniel González Cabanelas <dgcbueu@gmail.com>

[ 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>
---
drivers/media/pci/cx88/cx88-mpeg.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/media/pci/cx88/cx88-mpeg.c b/drivers/media/pci/cx88/cx88-mpeg.c
index a57c991b165b..10d2971ef062 100644
--- a/drivers/media/pci/cx88/cx88-mpeg.c
+++ b/drivers/media/pci/cx88/cx88-mpeg.c
@@ -162,6 +162,9 @@ 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);
--
2.34.1