cx23885[v2]: Fix IR interrupt storm.
Commit Message
Hi all,
This path is meant to be up-streamed.
Andy has a nice explanation for the interrupt storm when
enabling the IR interrupt:
The flatiron core (the audio adc) signals the end of its self-test
with an interrupt. Since the flatiron irq seems OR-wired
with the IR irq the result is this interrupt storm.
This i2c tranfers will clear the flatiron interrupts - the left
and right channels self-tests.
Also as suggested by Andy I moved the i2c transfers to the
cx23885 av core interrupt handling worker. If any spurious
interrupt happens we silence them.
The flatiron has some dedicated register read/write functions but are
not exported so Antti just suggested to call the i2c_transfer directly.
Tested in the TBS6981 Dual DVB-S2 card.
PS: I've found this i2c_transfers in TBS media tree, more precisely
in the cx23885-i2c.c file.
Regards,
Luis
Signed-off-by: Luis Alves <ljalvs@gmail.com>
---
drivers/media/pci/cx23885/cx23885-av.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
@@ -29,8 +29,25 @@ void cx23885_av_work_handler(struct work_struct *work)
struct cx23885_dev *dev =
container_of(work, struct cx23885_dev, cx25840_work);
bool handled;
+ char buffer[2];
+ struct i2c_msg msg = {
+ .addr = 0x98 >> 1,
+ .flags = 0,
+ .len = 2,
+ .buf = buffer,
+ };
v4l2_subdev_call(dev->sd_cx25840, core, interrupt_service_routine,
PCI_MSK_AV_CORE, &handled);
+
+ if (!handled) {
+ /* clear any pending flatiron interrupts */
+ buffer[0] = 0x1f;
+ buffer[1] = 0x80;
+ i2c_transfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
+ buffer[0] = 0x23;
+ i2c_transfer(&dev->i2c_bus[2].i2c_adap, &msg, 1);
+ }
+
cx23885_irq_enable(dev, PCI_MSK_AV_CORE);
}