Hi Martin,

On Wed, May 19, 2021 at 05:21:11PM +0200, Martin Kepplinger wrote:

Am Mittwoch, dem 19.05.2021 um 04:14 +0300 schrieb Laurent Pinchart:

quoted

On Tue, May 18, 2021 at 04:39:00PM +0200, Martin Kepplinger wrote:

quoted

Am Sonntag, dem 16.05.2021 um 01:55 +0300 schrieb Laurent Pinchart:

quoted

On Tue, May 04, 2021 at 05:59:39PM +0200, Martin Kepplinger wrote:

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hi Laurent, again thanks a lot for posting this series! I can't fully test
it, but base my work for imx8mq on it now. imx8mq includes
yet another mipi phy version than this and below is some very rough testing
code. it's not at all something I sign-off on but my following
problem is based on it.

Unless I'm mistaken, the CSI-2 receiver in the i.MX8MQ is a completely
different device. I wouldn't try to support it in the imx7-mipi-csis
driver, but in a separate driver.

quoted

 * configured to use both staging csi drivers
 * the csi bridge driver at least streams frames together with the
nxp "yav" mipi driver

media-ctl -p now says the output below, so one link from mipi to
csi is missing.

Note that

media-ctl --set-v4l2 "'csi':0 [fmt:SBGGR10/640x480]"
works in that it changes the configured format below, but

media-ctl -l "'imx7-mipi-csis.0':1" -> "'csi':0[1]"
doesn't create said missing link.

media-ctl can't create links, it can only enable or disable them. Link
creation is the prerogative of drivers.

quoted

Do I maybe use that wrongly? If now, does anything come to mind that would
be missing specifically?

The link should be created by the call to media_create_pad_link() in
imx_media_capture_device_register(). You'll need to figure out if the
function is called and returns an error early, or if it doesn't get
called at all, and why.

quoted

When trying to stream anyway (if that makes sense), I get the
following:

[ 2008.377470] capture_start_streaming: starting
[ 2008.381883] capture_find_format: calling imx_media_find_mbus_format with code 0x2006
[ 2008.389671] imx7-csi 30a90000.csi1_bridge: capture_validate_fmt: capture_find_format err
[ 2008.397794] imx7-csi 30a90000.csi1_bridge: capture_validate_fmt: capture_find_format found colorspace 0x1 != 0x0
[ 2008.407999] imx7-csi 30a90000.csi1_bridge: capture format not valid: -32

and if I ignore that (because I'm not yet sure whether that is specific to
platforms including an IPU), I get a WARN_ON from vb2_start_streaming()

That I have a fix for, I'll post it as part of an imx7-media-csi
series.

Hi Laurent,

You haven't posted that fix you're talking about, right?

Correct. It's now fixed (see "[PATCH] media: imx: imx7-media-csi: Fix
buffer return upon stream start failure", I've CC'ed you).

quoted

The below
driver (attached; I'll send it as patches after I successfully tested
myself, and cleanup and fixes obviously)

Don't forget the DT bindings at that point :-)

quoted

results in the same situation I described above:

* missing link from mipi (entity 10) -> csi (entity 1):

The link is supposed to be created by
v4l2_create_fwnode_links_to_pad(),
called from imx7_csi_notify_bound(). Could you trace the calls and
figure out what goes wrong ?

that bound callback imx7_csi_notify_bound() is called only once during
probe: v4l2_create_fwnode_links_to_pad() returns 0 and
imx7_csi_async_register() returns success too.

What subdev is it called for (I assume the imx8mq-mipi-csis.0) ? Have
you traced inside the function to see why it doesn't create links ?

(the imx8mq mipi driver probes successfully, independently, a few ms
before the above, the sensor driver a few ms after that)

So nothing obviously going wrong during probe(). that's the call trace
in imx7_csi_notify_bound() :

[    5.992126] Call trace:
[    5.992129]  dump_backtrace+0x0/0x1e4
[    5.992149]  show_stack+0x24/0x30
[    5.992155]  dump_stack+0xd0/0x12c
[    5.992163]  imx7_csi_notify_bound+0x78/0x8c [imx7_media_csi]
[    5.992182]  v4l2_async_match_notify+0x58/0x1b0 [videodev]
[    5.992262]  v4l2_async_notifier_try_all_subdevs+0x60/0xd0 [videodev]
[    5.992316]  v4l2_async_match_notify+0x130/0x1b0 [videodev]
[    5.992370]  v4l2_async_register_subdev+0x98/0x1f0 [videodev]
[    5.992424]  imx7_csi_probe+0x2c8/0x310 [imx7_media_csi]
[    5.992436]  platform_probe+0x74/0xe4
[    5.992446]  really_probe+0xf0/0x510
[    5.992453]  driver_probe_device+0xfc/0x170
[    5.992458]  device_driver_attach+0xcc/0xd4
[    5.992464]  __driver_attach+0xb0/0x17c
[    5.992469]  bus_for_each_dev+0x7c/0xe0
[    5.992478]  driver_attach+0x30/0x40
[    5.992483]  bus_add_driver+0x154/0x250
[    5.992490]  driver_register+0x84/0x140
[    5.992496]  __platform_driver_register+0x34/0x40
[    5.992502]  imx7_csi_driver_init+0x2c/0x1000 [imx7_media_csi]
[    5.992515]  do_one_initcall+0x50/0x2d0
[    5.992522]  do_init_module+0x60/0x274
[    5.992532]  load_module+0x2078/0x2450
[    5.992539]  __do_sys_finit_module+0xbc/0x130
[    5.992547]  __arm64_sys_finit_module+0x2c/0x3c
[    5.992555]  el0_svc_common.constprop.0+0x68/0x130
[    5.992565]  do_el0_svc+0x28/0x34
[    5.992571]  el0_svc+0x2c/0x54
[    5.992580]  el0_sync_handler+0x1a4/0x1b0
[    5.992587]  el0_sync+0x174/0x180


btw, my test is:

v4l2-ctl -d "/dev/v4l/by-path/platform-30a90000.csi1_bridge-video-
index0" --set-fmt-video=width=640,height=480 --stream-mmap --stream-
to=test.raw --stream-count=1

and that (probably because of the missing link) fails with

VIDIOC_STREAMON returned -1 (No such device)

which is in the kernel:

imx7-csi 30a90000.csi1_bridge: pipeline start failed with -19

Let's fix the missing link first.

-- 
Regards,

Laurent Pinchart