Failure to stop CAMSS stream (sc8280xp)

[Johan Hovold <johan@kernel.org>]

Hi,

I've been testing Bryan's work that enables the camera on the Lenovo
ThinkPad X13s and keep triggering the below warnings when stopping a
stream (e.g. closing qcam) which indicate that this is a driver bug.

After this happens qcam fails to start again (something returns -EBUSY).

Is this a known issue with CAMSS or is something missing in the sc8280xp
integration?

I'm using the following (squashed) devicetree patch from Bryan to enable
the camera (everything else is upstream):

	https://github.com/jhovold/linux/commit/85b41b8d0efd418509df548592f95b43b9663409

The issue was there with 6.9 as well so it's not a (recent) regression.

Probing the camera sometimes, but infrequently, also fails with:

	qcom-camss ac5a000.camss: Failed to power up pipeline: -13

and I'm seeing the following warning on every boot:

	i2c-qcom-cci ac4c000.cci: Found 19200000 cci clk rate while 37500000 was expected

Johan


[ 1265.509677] ------------[ cut here ]------------
[ 1265.509831] WARNING: CPU: 5 PID: 919 at drivers/media/common/videobuf2/videobuf2-core.c:2183 __vb2_queue_cancel+0x230/0x2c8 [videobuf2_common]
...
[ 1265.510417] CPU: 5 PID: 919 Comm: qcam Not tainted 6.10.0-rc5 #124
[ 1265.510428] Hardware name: LENOVO 21BYZ9SRUS/21BYZ9SRUS, BIOS N3HET87W (1.59 ) 12/05/2023
...
[ 1265.510630] Call trace:
[ 1265.510636]  __vb2_queue_cancel+0x230/0x2c8 [videobuf2_common]
[ 1265.510648]  vb2_core_streamoff+0x24/0xcc [videobuf2_common]
[ 1265.510660]  vb2_ioctl_streamoff+0x5c/0xa8 [videobuf2_v4l2]
[ 1265.510673]  v4l_streamoff+0x24/0x30 [videodev]
[ 1265.510707]  __video_do_ioctl+0x190/0x3f4 [videodev]
[ 1265.510732]  video_usercopy+0x304/0x8c4 [videodev]
[ 1265.510757]  video_ioctl2+0x18/0x34 [videodev]
[ 1265.510782]  v4l2_ioctl+0x40/0x60 [videodev]
[ 1265.510807]  __arm64_sys_ioctl+0xa8/0xec
[ 1265.510820]  invoke_syscall+0x48/0x118
[ 1265.510834]  el0_svc_common.constprop.0+0x40/0xe0
[ 1265.510845]  do_el0_svc+0x1c/0x28
[ 1265.510856]  el0_svc+0x48/0x114
[ 1265.510867]  el0t_64_sync_handler+0xc0/0xc4
[ 1265.510876]  el0t_64_sync+0x190/0x194
[ 1265.510885] irq event stamp: 279668
[ 1265.510892] hardirqs last  enabled at (279667): [<ffffa0c6a09d7754>] _raw_spin_unlock_irqrestore+0x74/0x78
[ 1265.510904] hardirqs last disabled at (279668): [<ffffa0c6a09c8860>] el1_dbg+0x24/0x8c
[ 1265.510913] softirqs last  enabled at (279636): [<ffffa0c69ffe76e4>] fpsimd_restore_current_state+0x34/0xc4
[ 1265.510924] softirqs last disabled at (279634): [<ffffa0c69ffe76b4>] fpsimd_restore_current_state+0x4/0xc4
[ 1265.510935] ---[ end trace 0000000000000000 ]---
[ 1265.510944] videobuf2_common: driver bug: stop_streaming operation is leaving buffer 0 in active state
[ 1265.511175] videobuf2_common: driver bug: stop_streaming operation is leaving buffer 1 in active state
[ 1265.511398] videobuf2_common: driver bug: stop_streaming operation is leaving buffer 2 in active state