1107549 Commits

Author SHA1 Message Date
Javier Martinez Canillas
94dc3471d1
drm: Use size_t type for len variable in drm_copy_field()
The strlen() function returns a size_t which is an unsigned int on 32-bit
arches and an unsigned long on 64-bit arches. But in the drm_copy_field()
function, the strlen() return value is assigned to an 'int len' variable.

Later, the len variable is passed as copy_from_user() third argument that
is an unsigned long parameter as well.

In theory, this can lead to an integer overflow via type conversion. Since
the assignment happens to a signed int lvalue instead of a size_t lvalue.

In practice though, that's unlikely since the values copied are set by DRM
drivers and not controlled by userspace. But using a size_t for len is the
correct thing to do anyways.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220705100215.572498-2-javierm@redhat.com
2022-07-15 10:25:01 +02:00
Maxime Ripard
887ddf3251
drm/vc4: v3d: Switch to devm_pm_runtime_enable
devm_pm_runtime_enable() simplifies the driver a bit since it will call
pm_runtime_disable() automatically through a device-managed action.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-70-maxime@cerno.tech
2022-07-13 10:46:13 +02:00
Maxime Ripard
266cff37d7
drm/vc4: v3d: Rework the runtime_pm setup
At bind time, vc4_v3d_bind() will read a register to retrieve the v3d
version and make sure it's a version we're compatible with.

However, the v3d has an optional clock that is enabled only after the
register read-out and a power domain that wasn't enabled at all in the bind
implementation. This was working fine at boot because both were enabled,
but resulted in the version check failing if we were unbinding and
rebinding the driver because the unbinding would have turned them off.

The fix isn't as easy as calling pm_runtime_resume_and_get() prior to the
register access to power up the power domain though.

Indeed, the runtime_resume implementation will enable the clock mentioned
above, call vc4_v3d_init_hw() and then vc4_irq_enable().

Prior to the previous patch, vc4_irq_enable() needed to occur after our
call to platform_get_irq() and vc4_irq_install(), since vc4_irq_enable()
used to call enable_irq() and vc4_irq_install() will call request_irq().

vc4_irq_install() will also do some register access, so needs the power
domain to be on. So we ended up in a situation where
vc4_v3d_runtime_resume() needed vc4_irq_install() to have been called
before, and vc4_irq_install() needed vc4_v3d_runtime_resume().

The previous patch removed the enable_irq() call in vc4_irq_enable() and
thus removed the dependency of vc4_v3d_runtime_resume() on
vc4_irq_install().

Thus, we can now rework our bind implementation to call
pm_runtime_resume_and_get() before our register access to make sure the
power domain is on. vc4_v3d_runtime_resume() also takes care of turning the
clock on and calling vc4_v3d_init_hw() so we can remove them from bind.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-69-maxime@cerno.tech
2022-07-13 10:46:13 +02:00
Maxime Ripard
9b6f461582
drm/vc4: v3d: Stop disabling interrupts
The vc4_irq_disable(), among other things, will call disable_irq() to
complete any in-flight interrupts.

This requires its counterpart, vc4_irq_enable(), to call enable_irq() which
causes issues addressed in a later patch.

However, vc4_irq_disable() is called by two callees: vc4_irq_uninstall()
and vc4_v3d_runtime_suspend().

vc4_irq_uninstall() also calls free_irq() which already disables the
interrupt line. We thus don't require an explicit disable_irq() for that
call site.

vc4_v3d_runtime_suspend() doesn't have any other code. However, the rest of
vc4_irq_disable() masks the interrupts coming from the v3d, so explictly
disabling the interrupt line is also redundant.

The only thing we really care about is thus to make sure we don't have any
handler in-flight, as suggested by the comment. We can thus replace
disable_irq() by synchronize_irq().

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-68-maxime@cerno.tech
2022-07-13 10:46:13 +02:00
Maxime Ripard
57d68ee8f7
drm/vc4: perfmon: Add missing mutex_destroy
vc4_perfmon_open_file() will instantiate a mutex for that file instance,
but we never call mutex_destroy () in vc4_perfmon_close_file().

Let's add that missing call.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-67-maxime@cerno.tech
2022-07-13 10:46:13 +02:00
Maxime Ripard
374146cad4
drm/vc4: Switch to drmm_mutex_init
mutex_init is supposed to be balanced by a call to mutex_destroy that we
were never doing in the vc4 driver.

Since a DRM-managed mutex_init variant has been introduced, let's just
switch to it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-66-maxime@cerno.tech
2022-07-13 10:46:13 +02:00
Maxime Ripard
445b287e18
drm/vc4: debugfs: Simplify debugfs registration
The vc4 has a custom API to allow components to register a debugfs file
before the DRM driver has been registered and the debugfs_init hook has
been called.

However, the .late_register hook allows to have the debugfs file creation
deferred after that time already.

Let's remove our custom code to only register later our debugfs entries as
part of either debugfs_init or after it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-65-maxime@cerno.tech
2022-07-13 10:46:13 +02:00
Maxime Ripard
fe3b0f784c
drm/vc4: debugfs: Return an error on failure
vc4_debugfs_add_file() can fail, so let's propagate its error code instead
of silencing it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-64-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
be919b89b2
drm/vc4: debugfs: Protect device resources
Our current code now mixes some resources whose lifetime are tied to the
device (clocks, IO mappings, etc.) and some that are tied to the DRM device
(encoder, bridge).

The device one will be freed at unbind time, but the DRM one will only be
freed when the last user of the DRM device closes its file handle.

So we end up with a time window during which we can call the encoder hooks,
but we don't have access to the underlying resources and device.

Let's protect all those sections with drm_dev_enter() and drm_dev_exit() so
that we bail out if we are during that window.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-63-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
4e06fd9c7c
drm/vc4: vec: Switch to devm_pm_runtime_enable
devm_pm_runtime_enable() simplifies the driver a bit since it will call
pm_runtime_disable() automatically through a device-managed action.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-62-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
f0601ef863
drm/vc4: vec: Protect device resources after removal
Whenever the device and driver are unbound, the main device and all the
subdevices will be removed by calling their unbind() method.

However, the DRM device itself will only be freed when the last user will
have closed it.

It means that there is a time window where the device and its resources
aren't there anymore, but the userspace can still call into our driver.

Fortunately, the DRM framework provides the drm_dev_enter() and
drm_dev_exit() functions to make sure our underlying device is still there
for the section protected by those calls. Let's add them to the VEC driver.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-61-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
881f6d945b
drm/vc4: vec: Switch to DRM-managed connector initialization
The current code will call drm_connector_unregister() and
drm_connector_cleanup() when the device is unbound. However, by then, there
might still be some references held to that connector, including by the
userspace that might still have the DRM device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-60-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
c62f432f2e
drm/vc4: vec: Switch to DRM-managed encoder initialization
The current code will call drm_encoder_cleanup() when the device is
unbound. However, by then, there might still be some references held to
that encoder, including by the userspace that might still have the DRM
device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-59-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
cd2444a795
drm/vc4: vec: Remove call to drm_connector_unregister()
drm_connector_unregister() is only to be used for connectors that have been
registered through drm_connector_register() after drm_dev_register() has
been called. This is our case here so let's remove the call.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-58-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
fe7289e218
drm/vc4: vec: Switch to drmm_kzalloc
Our internal structure that stores the DRM entities structure is allocated
through a device-managed kzalloc.

This means that this will eventually be freed whenever the device is
removed. In our case, the most likely source of removal is that the main
device is going to be unbound, and component_unbind_all() is being run.

However, it occurs while the DRM device is still registered, which will
create dangling pointers, eventually resulting in use-after-free.

Switch to a DRM-managed allocation to keep our structure until the DRM
driver doesn't need it anymore.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-57-maxime@cerno.tech
2022-07-13 10:46:12 +02:00
Maxime Ripard
9780315b06
drm/vc4: vec: Embed DRM structures into the private structure
The VC4 VEC driver private structure contains only a pointer to the
encoder and connector it implements. This makes the overall structure
somewhat inconsistent with the rest of the driver, and complicates its
initialisation without any apparent gain.

Let's embed the drm_encoder structure (through the vc4_encoder one) and
drm_connector into struct vc4_vec to fix both issues.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-56-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
a0883e4df2
drm/vc4: vec: Remove vc4_dev vec pointer
There's no user for that pointer so let's just get rid of it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-55-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
b7345c9799
drm/vc4: txp: Protect device resources
Our current code now mixes some resources whose lifetime are tied to the
device (clocks, IO mappings, etc.) and some that are tied to the DRM device
(encoder, bridge).

The device one will be freed at unbind time, but the DRM one will only be
freed when the last user of the DRM device closes its file handle.

So we end up with a time window during which we can call the encoder hooks,
but we don't have access to the underlying resources and device.

Let's protect all those sections with drm_dev_enter() and drm_dev_exit() so
that we bail out if we are during that window.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-54-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
d67210bbe5
drm/vc4: txp: Remove call to drm_connector_unregister()
drm_connector_unregister() is only to be used for connectors that have been
registered through drm_connector_register() after drm_dev_register() has
been called. This is our case here so let's remove the call.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-53-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
b0da34c797
drm/vc4: txp: Switch to drmm_kzalloc
Our internal structure that stores the DRM entities structure is allocated
through a device-managed kzalloc.

This means that this will eventually be freed whenever the device is
removed. In our case, the most likely source of removal is that the main
device is going to be unbound, and component_unbind_all() is being run.

However, it occurs while the DRM device is still registered, which will
create dangling pointers, eventually resulting in use-after-free.

Switch to a DRM-managed allocation to keep our structure until the DRM
driver doesn't need it anymore.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-52-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
260ad78e9d
drm/vc4: txp: Remove duplicate regset
There's already a regset in the vc4_crtc structure so there's no need to
duplicate it in vc4_txp.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-51-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
121b1a5f47
drm/vc4: txp: Remove vc4_dev txp pointer
There's no user for that pointer so let's just get rid of it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-50-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
932d860f46
drm/vc4: hdmi: Switch to devm_pm_runtime_enable
devm_pm_runtime_enable() simplifies the driver a bit since it will call
pm_runtime_disable() automatically through a device-managed action.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-49-maxime@cerno.tech
2022-07-13 10:46:11 +02:00
Maxime Ripard
cd00ed5187
drm/vc4: hdmi: Protect device resources after removal
Whenever the device and driver are unbound, the main device and all the
subdevices will be removed by calling their unbind() method.

However, the DRM device itself will only be freed when the last user will
have closed it.

It means that there is a time window where the device and its resources
aren't there anymore, but the userspace can still call into our driver.

Fortunately, the DRM framework provides the drm_dev_enter() and
drm_dev_exit() functions to make sure our underlying device is still there
for the section protected by those calls. Let's add them to the HDMI driver.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-48-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
0c9d0ddd9c
drm/vc4: hdmi: Move audio structure offset checks
The HDMI driver unbind hook doesn't have any ALSA-related code anymore, so
let's move the ALSA sanity checks and comments we have to some other part
of the driver dedicated to ALSA.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-47-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
af8a3b125b
drm/vc4: hdmi: Use devm to register hotplug interrupts
Commit 776efe800fed ("drm/vc4: hdmi: Drop devm interrupt handler for
hotplug interrupts") dropped the device-managed interrupt registration
because it was creating bugs and races whenever an interrupt was coming in
while the device was removed.

However, our latest patches to the HDMI controller driver fix this as well,
so we can use device-managed interrupt handlers again.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-46-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
a3dbb1c016
drm/vc4: hdmi: Switch to DRM-managed kfree to build regsets
The current code to build the registers set later exposed in debugfs for
the HDMI controller relies on traditional allocations, that are later
free'd as part of the driver unbind hook.

Since krealloc doesn't have a DRM-managed equivalent, let's add an action
to free the buffer later on.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-45-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
d3a84242f8
drm/vc4: hdmi: Use a device-managed action for DDC
The reference to the DDC controller device needs to be put back when we're
done with it. Let's use a device-managed action to simplify the driver.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-44-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
015653f7af
drm/vc4: hdmi: Switch to device-managed CEC initialization
The current code to unregister our CEC device needs to be undone manually
when we remove the HDMI driver.

Since the CEC framework will allocate its main structure, and will defer
its deallocation to when the last user will have closed it, we don't really
need to take any particular measure to prevent any use-after-free and can
thus use any managed action.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-43-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
59f9d46af4
drm/vc4: hdmi: Switch to device-managed ALSA initialization
The current code to unregister our ALSA device needs to be undone manually
when we remove the HDMI driver.

Since ALSA doesn't seem to support any mechanism to defer freeing something
until the last user of the ALSA device is gone, we can either use a
device-managed or a DRM-managed action.

The consistent way would be to use a DRM-managed one, just like pretty much
any framework-facing structure should be doing. However, ALSA does a lot of
allocation and registration using device-managed calls. Thus, if we're
going that way, by the time the DRM-managed action would run all of those
allocation would have been freed and we would end up with a use-after-free.

Thus, let's do a device-managed action. It's been tested with KASAN enabled
and doesn't seem to trigger any issue, so it's as good as anything.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-42-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
19d094c3a1
drm/vc4: hdmi: Switch to DRM-managed connector initialization
The current code will call drm_connector_unregister() and
drm_connector_cleanup() when the device is unbound. However, by then, there
might still be some references held to that connector, including by the
userspace that might still have the DRM device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-41-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
56924791cd
drm/vc4: hdmi: Switch to DRM-managed encoder initialization
The current code will call drm_encoder_cleanup() when the device is
unbound. However, by then, there might still be some references held to
that encoder, including by the userspace that might still have the DRM
device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-40-maxime@cerno.tech
2022-07-13 10:46:10 +02:00
Maxime Ripard
7a951e3a26
drm/vc4: hdmi: Remove call to drm_connector_unregister()
drm_connector_unregister() is only to be used for connectors that have been
registered through drm_connector_register() after drm_dev_register() has
been called. This is our case here so let's remove the call.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-39-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
b4f2c70c1a
drm/vc4: hdmi: Switch to drmm_kzalloc
Our internal structure that stores the DRM entities structure is allocated
through a device-managed kzalloc.

This means that this will eventually be freed whenever the device is
removed. In our case, the most likely source of removal is that the main
device is going to be unbound, and component_unbind_all() is being run.

However, it occurs while the DRM device is still registered, which will
create dangling pointers, eventually resulting in use-after-free.

Switch to a DRM-managed allocation to keep our structure until the DRM
driver doesn't need it anymore.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-38-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
7b44e4de72
drm/vc4: dsi: Switch to devm_pm_runtime_enable
devm_pm_runtime_enable() simplifies the driver a bit since it will call
pm_runtime_disable() automatically through a device-managed action.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-37-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
6eda156429
drm/vc4: dsi: Fix the driver structure lifetime
The vc4_dsi structure is currently allocated through a device-managed
allocation. This can lead to use-after-free issues however in the unbinding
path since the DRM entities will stick around, but the underlying structure
has been freed.

However, we can't just fix it by using a DRM-managed allocation like we did
for the other drivers since the DSI case is a bit more intricate.

Indeed, the structure will be allocated at probe time, when we don't have a
DRM device yet, to be able to register the DSI bus driver. We will then
reuse it at bind time to register our KMS entities in the framework.

In order to work around both constraints, we can use a kref to track the
users of the structure (DSI host, and KMS), and then put our structure when
the DSI host will have been unregistered, and through a DRM-managed action
that will execute once we won't need the KMS entities anymore.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-36-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
2a87d48c33
drm/vc4: dsi: Switch to drmm_of_get_bridge
The current code uses a device-managed function to retrieve the next bridge
downstream.

However, that means that it will be removed at unbind time, where the DRM
device is still very much live and might still have some applications that
still have it open.

Switch to a DRM-managed variant to clean everything up once the DRM device
has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-35-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
6f0ca506c3
drm/vc4: dsi: Switch to DRM-managed encoder initialization
The current code will call drm_encoder_cleanup() when the device is
unbound. However, by then, there might still be some references held to
that encoder, including by the userspace that might still have the DRM
device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-34-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
73b68b28a9
drm/vc4: dsi: Embed DRM structures into the private structure
The VC4 DSI driver private structure contains only a pointer to the
encoder it implements. This makes the overall structure somewhat
inconsistent with the rest of the driver, and complicates its
initialisation without any apparent gain.

Let's embed the drm_encoder structure (through the vc4_encoder one) into
struct vc4_dsi to fix both issues.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-33-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
71b1bd4c2b
drm/vc4: dpi: Protect device resources
Our current code now mixes some resources whose lifetime are tied to the
device (clocks, IO mappings, etc.) and some that are tied to the DRM device
(encoder, bridge).

The device one will be freed at unbind time, but the DRM one will only be
freed when the last user of the DRM device closes its file handle.

So we end up with a time window during which we can call the encoder hooks,
but we don't have access to the underlying resources and device.

Let's protect all those sections with drm_dev_enter() and drm_dev_exit() so
that we bail out if we are during that window.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-32-maxime@cerno.tech
2022-07-13 10:46:09 +02:00
Maxime Ripard
055af0235a
drm/vc4: dpi: Switch to drmm_of_get_bridge
The current code uses a device-managed function to retrieve the next bridge
downstream.

However, that means that it will be removed at unbind time, where the DRM
device is still very much live and might still have some applications that
still have it open.

Switch to a DRM-managed variant to clean everything up once the DRM device
has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-31-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
e126d31800
drm/vc4: dpi: Switch to DRM-managed encoder initialization
The current code will call drm_encoder_cleanup() when the device is
unbound. However, by then, there might still be some references held to
that encoder, including by the userspace that might still have the DRM
device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-30-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
77932adf2a
drm/vc4: dpi: Add action to disable the clock
The DPI controller has two clocks called core and pixel, the core clock
being enabled at bind time.

Adding a device-managed action will make the error path easier, so let's
create one to disable it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-29-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
5801eda938
drm/vc4: dpi: Remove unnecessary drm_of_panel_bridge_remove call
Since we have a managed call to create our panel_bridge instance, the call
to drm_of_panel_bridge_remove() at unbind is both redundant and dangerous
since it might lead to a use-after-free.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-28-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
ff5b18ce8a
drm/vc4: dpi: Return an error if we can't enable our clock
If we fail to enable the DPI clock, we just ignore the error and moves
forward. Let's return an error instead.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-27-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
7f0ba8f98a
drm/vc4: dpi: Switch to drmm_kzalloc
Our internal structure that stores the DRM entities structure is allocated
through a device-managed kzalloc.

This means that this will eventually be freed whenever the device is
removed. In our case, the most likely source of removal is that the main
device is going to be unbound, and component_unbind_all() is being run.

However, it occurs while the DRM device is still registered, which will
create dangling pointers, eventually resulting in use-after-free.

Switch to a DRM-managed allocation to keep our structure until the DRM
driver doesn't need it anymore.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-26-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
7c9a4bab7a
drm/vc4: dpi: Embed DRM structures into the private structure
The VC4 DPI driver private structure contains only a pointer to the
encoder it implements. This makes the overall structure somewhat
inconsistent with the rest of the driver, and complicates its
initialisation without any apparent gain.

Let's embed the drm_encoder structure (through the vc4_encoder one) into
struct vc4_dpi to fix both issues.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-25-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
693e35dcde
drm/vc4: dpi: Remove vc4_dev dpi pointer
There's no user for that pointer so let's just get rid of it.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-24-maxime@cerno.tech
2022-07-13 10:46:08 +02:00
Maxime Ripard
77ef4c1702
drm/vc4: crtc: Switch to DRM-managed CRTC initialization
The current code will call drm_crtc_cleanup() when the device is
unbound. However, by then, there might still be some references held to
that CRTC, including by the userspace that might still have the DRM
device open.

Let's switch to a DRM-managed initialization to clean up after ourselves
only once the DRM device has been last closed.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-23-maxime@cerno.tech
2022-07-13 10:46:07 +02:00
Maxime Ripard
7cc4214c27
drm/vc4: crtc: Switch to drmm_kzalloc
Our internal structure that stores the DRM entities structure is allocated
through a device-managed kzalloc.

This means that this will eventually be freed whenever the device is
removed. In our case, the most likely source of removal is that the main
device is going to be unbound, and component_unbind_all() is being run.

However, it occurs while the DRM device is still registered, which will
create dangling pointers, eventually resulting in use-after-free.

Switch to a DRM-managed allocation to keep our structure until the DRM
driver doesn't need it anymore.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-22-maxime@cerno.tech
2022-07-13 10:46:07 +02:00