linux-toradex.git/drivers/dpll/dpll_netlink.c, branch v7.0-rc2

dpll: Add notifier chain for dpll events

2026-02-05T14:57:46+00:00

Currently, the DPLL subsystem reports events (creation, deletion, changes)
to userspace via Netlink. However, there is no mechanism for other kernel
components to be notified of these events directly.

Add a raw notifier chain to the DPLL core protected by dpll_lock. This
allows other kernel subsystems or drivers to register callbacks and
receive notifications when DPLL devices or pins are created, deleted,
or modified.

Define the following:
- Registration helpers: {,un}register_dpll_notifier()
- Event types: DPLL_DEVICE_CREATED, DPLL_PIN_CREATED, etc.
- Context structures: dpll_{device,pin}_notifier_info  to pass relevant
  data to the listeners.

The notification chain is invoked alongside the existing Netlink event
generation to ensure in-kernel listeners are kept in sync with the
subsystem state.

Reviewed-by: Vadim Fedorenko 
Co-developed-by: Ivan Vecera 
Signed-off-by: Ivan Vecera 
Signed-off-by: Petr Oros 
Reviewed-by: Arkadiusz Kubalewski 
Reviewed-by: Aleksandr Loktionov 
Link: https://patch.msgid.link/20260203174002.705176-4-ivecera@redhat.com
Signed-off-by: Paolo Abeni

dpll: expose fractional frequency offset in ppt

2026-01-30T02:21:16+00:00

Currently, the dpll subsystem exports the fractional frequency offset
(FFO) in parts per million (ppm). This granularity is insufficient for
high-precision synchronization scenarios which often require parts per
trillion (ppt) resolution.

Add a new netlink attribute DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT
to expose the FFO in ppt.

Update the dpll netlink core to expect the driver-provided FFO value
to be in ppt. To maintain backward compatibility with existing userspace
tools, populate the legacy DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET
attribute by dividing the new ppt value by 1,000,000.

Update the zl3073x and mlx5 drivers to provide the FFO value in ppt:
- zl3073x: adjust the fixed-point calculation to produce ppt (10^12)
  instead of ppm (10^6).
- mlx5: scale the existing ppm value by 1,000,000.

Signed-off-by: Ivan Vecera 
Reviewed-by: Arkadiusz Kubalewski 
Reviewed-by: Jiri Pirko 
Link: https://patch.msgid.link/20260126162253.27890-1-ivecera@redhat.com
Signed-off-by: Jakub Kicinski

dpll: add dpll_device op to set working mode

2026-01-19T20:04:53+00:00

Currently, userspace can retrieve the DPLL working mode but cannot
configure it. This prevents changing the device operation, such as
switching from manual to automatic mode and vice versa.

Add a new callback .mode_set() to struct dpll_device_ops. Extend
the netlink policy and device-set command handling to process
the DPLL_A_MODE attribute.  Update the netlink YAML specification
to include the mode attribute in the device-set operation.

Reviewed-by: Vadim Fedorenko 
Signed-off-by: Ivan Vecera 
Link: https://patch.msgid.link/20260114122726.120303-3-ivecera@redhat.com
Signed-off-by: Jakub Kicinski

dpll: add dpll_device op to get supported modes

2026-01-19T20:04:53+00:00

Currently, the DPLL subsystem assumes that the only supported mode is
the one currently active on the device. When dpll_msg_add_mode_supported()
is called, it relies on ops->mode_get() and reports that single mode
to userspace. This prevents users from discovering other modes the device
might be capable of.

Add a new callback .supported_modes_get() to struct dpll_device_ops. This
allows drivers to populate a bitmap indicating all modes supported by
the hardware.

Update dpll_msg_add_mode_supported() to utilize this new callback:

* if ops->supported_modes_get is defined, use it to retrieve the full
  bitmap of supported modes.
* if not defined, fall back to the existing behavior: retrieve
  the current mode via ops->mode_get and set the corresponding bit
  in the bitmap.

Finally, iterate over the bitmap and add a DPLL_A_MODE_SUPPORTED netlink
attribute for every set bit, accurately reporting the device's capabilities
to userspace.

Reviewed-by: Vadim Fedorenko 
Signed-off-by: Ivan Vecera 
Link: https://patch.msgid.link/20260114122726.120303-2-ivecera@redhat.com
Signed-off-by: Jakub Kicinski

dpll: add phase-adjust-gran pin attribute

2025-11-01T00:59:17+00:00

Phase-adjust values are currently limited by a min-max range. Some
hardware requires, for certain pin types, that values be multiples of
a specific granularity, as in the zl3073x driver.

Add a `phase-adjust-gran` pin attribute and an appropriate field in
dpll_pin_properties. If set by the driver, use its value to validate
user-provided phase-adjust values.

Reviewed-by: Michal Schmidt 
Reviewed-by: Petr Oros 
Tested-by: Prathosh Satish 
Signed-off-by: Ivan Vecera 
Reviewed-by: Jiri Pirko 
Reviewed-by: Arkadiusz Kubalewski 
Link: https://patch.msgid.link/20251029153207.178448-2-ivecera@redhat.com
Signed-off-by: Jakub Kicinski

dpll: fix device-id-get and pin-id-get to return errors properly

2025-10-29T00:50:18+00:00

The device-id-get and pin-id-get handlers were ignoring errors from
the find functions and sending empty replies instead of returning
error codes to userspace.

When dpll_device_find_from_nlattr() or dpll_pin_find_from_nlattr()
returned an error (e.g., -EINVAL for "multiple matches" or -ENODEV
for "not found"), the handlers checked `if (!IS_ERR(ptr))` and
skipped adding the device/pin handle to the message, but then still
sent the empty message as a successful reply.

This caused userspace tools to receive empty responses with id=0
instead of proper netlink errors with extack messages like
"multiple matches".

The bug is visible via strace, which shows the kernel sending TWO
netlink messages in response to a single request:

1. Empty reply (20 bytes, just header, no attributes):
   recvfrom(3, [{nlmsg_len=20, nlmsg_type=dpll, nlmsg_flags=0, ...},
                {cmd=0x7, version=1}], ...)

2. NLMSG_ERROR ACK with extack (because of NLM_F_ACK flag):
   recvfrom(3, [{nlmsg_len=60, nlmsg_type=NLMSG_ERROR,
                 nlmsg_flags=NLM_F_CAPPED|NLM_F_ACK_TLVS, ...},
                [{error=0, msg={...}},
                 [{nla_type=NLMSGERR_ATTR_MSG}, "multiple matches"]]], ...)

The C YNL library parses the first message, sees an empty response,
and creates a result object with calloc() which zero-initializes all
fields, resulting in id=0.

The Python YNL library parses both messages and displays the extack
from the second NLMSG_ERROR message.

Fix by checking `if (IS_ERR(ptr))` first and returning the error
code immediately, so that netlink properly sends only NLMSG_ERROR with
the extack message to userspace. After this fix, both C and Python
YNL tools receive only the NLMSG_ERROR and behave consistently.

This affects:
- DPLL_CMD_DEVICE_ID_GET: now properly returns error when multiple
  devices match the criteria (e.g., same module-name + clock-id)
- DPLL_CMD_PIN_ID_GET: now properly returns error when multiple pins
  match the criteria (e.g., same module-name)

Before fix:
  $ dpll pin id-get module-name ice
  0  (wrong - should be error, there are 17 pins with module-name "ice")

After fix:
  $ dpll pin id-get module-name ice
  Error: multiple matches
  (correct - kernel reports the ambiguity via extack)

Fixes: 9d71b54b65b1 ("dpll: netlink: Add DPLL framework base functions")
Signed-off-by: Petr Oros 
Reviewed-by: Ivan Vecera 
Link: https://patch.msgid.link/20251024190733.364101-1-poros@redhat.com
Signed-off-by: Jakub Kicinski

dpll: add phase_offset_avg_factor_get/set callback ops

2025-09-30T01:57:41+00:00

Add new callback operations for a dpll device:
- phase_offset_avg_factor_get(...) - to obtain current phase offset
  averaging factor from dpll device,
- phase_offset_avg_factor_set(...) - to set phase offset averaging factor

Obtain the factor value using the get callback and provide it to the user
if the device driver implement this callback. Execute the set callback upon
user requests, if the driver implement it.

Signed-off-by: Ivan Vecera 
v2:
* do not require 'set' callback to retrieve current value
* always call 'set' callback regardless of current value
Reviewed-by: Vadim Fedorenko 
Link: https://patch.msgid.link/20250927084912.2343597-3-ivecera@redhat.com
Signed-off-by: Jakub Kicinski

dpll: fix clock quality level reporting

2025-09-14T20:03:40+00:00

The DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_EPRC is not reported via netlink
due to bug in dpll_msg_add_clock_quality_level(). The usage of
DPLL_CLOCK_QUALITY_LEVEL_MAX for both DECLARE_BITMAP() and
for_each_set_bit() is not correct because these macros requires bitmap
size and not the highest valid bit in the bitmap.

Use correct bitmap size to fix this issue.

Fixes: a1afb959add1 ("dpll: add clock quality level attribute and op")
Signed-off-by: Ivan Vecera 
Reviewed-by: Arkadiusz Kubalewski 
Link: https://patch.msgid.link/20250912093331.862333-1-ivecera@redhat.com
Signed-off-by: Jakub Kicinski

dpll: add reference sync get/set

2025-06-27T23:38:02+00:00

Define function for reference sync pin registration and callback ops to
set/get current feature state.

Implement netlink handler to fill netlink messages with reference sync
pin configuration of capable pins (pin-get).

Implement netlink handler to call proper ops and configure reference
sync pin state (pin-set).

Reviewed-by: Przemek Kitszel 
Reviewed-by: Milena Olech 
Reviewed-by: Jiri Pirko 
Signed-off-by: Arkadiusz Kubalewski 
Link: https://patch.msgid.link/20250626135219.1769350-3-arkadiusz.kubalewski@intel.com
Signed-off-by: Jakub Kicinski

dpll: add phase_offset_monitor_get/set callback ops

2025-06-14T01:21:57+00:00

Add new callback operations for a dpll device:
- phase_offset_monitor_get(..) - to obtain current state of phase offset
  monitor feature from dpll device,
- phase_offset_monitor_set(..) - to allow feature configuration.

Obtain the feature state value using the get callback and provide it to
the user if the device driver implements callbacks.

Execute the set callback upon user requests.

Reviewed-by: Milena Olech 
Reviewed-by: Jiri Pirko 
Signed-off-by: Arkadiusz Kubalewski 
Acked-by: Vadim Fedorenko 
Link: https://patch.msgid.link/20250612152835.1703397-3-arkadiusz.kubalewski@intel.com
Signed-off-by: Jakub Kicinski