kernel/linux.git/drivers/dpll/dpll_nl.c, branch linux-7.1.y

dpll: add frequency monitoring to netlink spec

2026-04-03T23:48:01+00:00

Add DPLL_A_FREQUENCY_MONITOR device attribute to allow control over the frequency monitor feature. The attribute uses the existing dpll_feature_state enum (enable/disable) and is present in both device-get reply and device-set request. Add DPLL_A_PIN_MEASURED_FREQUENCY pin attribute to expose the measured input frequency in millihertz (mHz). The attribute is present in the pin-get reply. Add DPLL_PIN_MEASURED_FREQUENCY_DIVIDER constant to allow userspace to extract integer and fractional parts. Reviewed-by: Vadim Fedorenko Signed-off-by: Ivan Vecera Link: https://patch.msgid.link/20260402184057.1890514-2-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

tools: ynl-gen: add regeneration comment

2025-11-26T03:20:42+00:00

Add a comment on regeneration to the generated files. The comment is placed after the YNL-GEN line[1], as to not interfere with ynl-regen.sh's detection logic. [1] and after the optional YNL-ARG line. Link: https://lore.kernel.org/r/aR5m174O7pklKrMR@zx2c4.com/ Suggested-by: Jason A. Donenfeld Signed-off-by: Asbjørn Sloth Tønnesen Acked-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20251120174429.390574-3-ast@fiberby.net Signed-off-by: Jakub Kicinski

dpll: add phase-offset-avg-factor device attribute to netlink spec

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

Add dpll device level attribute DPLL_A_PHASE_OFFSET_AVG_FACTOR to allow control over a calculation of reported phase offset value. Attribute is present, if the driver provides such capability, otherwise attribute shall not be present. Signed-off-by: Ivan Vecera Reviewed-by: Vadim Fedorenko Link: https://patch.msgid.link/20250927084912.2343597-2-ivecera@redhat.com Signed-off-by: Jakub Kicinski

dpll: add reference-sync netlink attribute

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

Add new netlink attribute to allow user space configuration of reference sync pin pairs, where both pins are used to provide one clock signal consisting of both: base frequency and sync signal. Reviewed-by: Przemek Kitszel Reviewed-by: Milena Olech Reviewed-by: Jiri Pirko Signed-off-by: Arkadiusz Kubalewski Link: https://patch.msgid.link/20250626135219.1769350-2-arkadiusz.kubalewski@intel.com Signed-off-by: Jakub Kicinski

dpll: add phase-offset-monitor feature to netlink spec

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

Add enum dpll_feature_state for control over features. Add dpll device level attribute: DPLL_A_PHASE_OFFSET_MONITOR - to allow control over a phase offset monitor feature. Attribute is present and shall return current state of a feature (enum dpll_feature_state), if the device driver provides such capability, otherwie attribute shall not be present. Reviewed-by: Aleksandr Loktionov Reviewed-by: Milena Olech Reviewed-by: Jiri Pirko Signed-off-by: Arkadiusz Kubalewski Acked-by: Vadim Fedorenko Link: https://patch.msgid.link/20250612152835.1703397-2-arkadiusz.kubalewski@intel.com Signed-off-by: Jakub Kicinski

dpll: add Embedded SYNC feature for a pin

2024-08-27T02:21:14+00:00

Implement and document new pin attributes for providing Embedded SYNC capabilities to the DPLL subsystem users through a netlink pin-get do/dump messages. Allow the user to set Embedded SYNC frequency with pin-set do netlink message. Reviewed-by: Aleksandr Loktionov Signed-off-by: Arkadiusz Kubalewski Reviewed-by: Jiri Pirko Link: https://patch.msgid.link/20240822222513.255179-2-arkadiusz.kubalewski@intel.com Signed-off-by: Jakub Kicinski

dpll: fix possible deadlock during netlink dump operation

2024-02-09T02:29:21+00:00

Recently, I've been hitting following deadlock warning during dpll pin dump: [52804.637962] ====================================================== [52804.638536] WARNING: possible circular locking dependency detected [52804.639111] 6.8.0-rc2jiri+ #1 Not tainted [52804.639529] ------------------------------------------------------ [52804.640104] python3/2984 is trying to acquire lock: [52804.640581] ffff88810e642678 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: netlink_dump+0xb3/0x780 [52804.641417] but task is already holding lock: [52804.642010] ffffffff83bde4c8 (dpll_lock){+.+.}-{3:3}, at: dpll_lock_dumpit+0x13/0x20 [52804.642747] which lock already depends on the new lock. [52804.643551] the existing dependency chain (in reverse order) is: [52804.644259] -> #1 (dpll_lock){+.+.}-{3:3}: [52804.644836] lock_acquire+0x174/0x3e0 [52804.645271] __mutex_lock+0x119/0x1150 [52804.645723] dpll_lock_dumpit+0x13/0x20 [52804.646169] genl_start+0x266/0x320 [52804.646578] __netlink_dump_start+0x321/0x450 [52804.647056] genl_family_rcv_msg_dumpit+0x155/0x1e0 [52804.647575] genl_rcv_msg+0x1ed/0x3b0 [52804.648001] netlink_rcv_skb+0xdc/0x210 [52804.648440] genl_rcv+0x24/0x40 [52804.648831] netlink_unicast+0x2f1/0x490 [52804.649290] netlink_sendmsg+0x36d/0x660 [52804.649742] __sock_sendmsg+0x73/0xc0 [52804.650165] __sys_sendto+0x184/0x210 [52804.650597] __x64_sys_sendto+0x72/0x80 [52804.651045] do_syscall_64+0x6f/0x140 [52804.651474] entry_SYSCALL_64_after_hwframe+0x46/0x4e [52804.652001] -> #0 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}: [52804.652650] check_prev_add+0x1ae/0x1280 [52804.653107] __lock_acquire+0x1ed3/0x29a0 [52804.653559] lock_acquire+0x174/0x3e0 [52804.653984] __mutex_lock+0x119/0x1150 [52804.654423] netlink_dump+0xb3/0x780 [52804.654845] __netlink_dump_start+0x389/0x450 [52804.655321] genl_family_rcv_msg_dumpit+0x155/0x1e0 [52804.655842] genl_rcv_msg+0x1ed/0x3b0 [52804.656272] netlink_rcv_skb+0xdc/0x210 [52804.656721] genl_rcv+0x24/0x40 [52804.657119] netlink_unicast+0x2f1/0x490 [52804.657570] netlink_sendmsg+0x36d/0x660 [52804.658022] __sock_sendmsg+0x73/0xc0 [52804.658450] __sys_sendto+0x184/0x210 [52804.658877] __x64_sys_sendto+0x72/0x80 [52804.659322] do_syscall_64+0x6f/0x140 [52804.659752] entry_SYSCALL_64_after_hwframe+0x46/0x4e [52804.660281] other info that might help us debug this: [52804.661077] Possible unsafe locking scenario: [52804.661671] CPU0 CPU1 [52804.662129] ---- ---- [52804.662577] lock(dpll_lock); [52804.662924] lock(nlk_cb_mutex-GENERIC); [52804.663538] lock(dpll_lock); [52804.664073] lock(nlk_cb_mutex-GENERIC); [52804.664490] The issue as follows: __netlink_dump_start() calls control->start(cb) with nlk->cb_mutex held. In control->start(cb) the dpll_lock is taken. Then nlk->cb_mutex is released and taken again in netlink_dump(), while dpll_lock still being held. That leads to ABBA deadlock when another CPU races with the same operation. Fix this by moving dpll_lock taking into dumpit() callback which ensures correct lock taking order. Fixes: 9d71b54b65b1 ("dpll: netlink: Add DPLL framework base functions") Signed-off-by: Jiri Pirko Reviewed-by: Arkadiusz Kubalewski Link: https://lore.kernel.org/r/20240207115902.371649-1-jiri@resnulli.us Signed-off-by: Jakub Kicinski

dpll: spec: add support for pin-dpll signal phase offset/adjust

2023-10-15T15:08:24+00:00

Add attributes for providing the user with: - measurement of signals phase offset between pin and dpll - ability to adjust the phase of pin signal Signed-off-by: Arkadiusz Kubalewski Signed-off-by: David S. Miller

dpll: spec: Add Netlink spec in YAML

2023-09-17T10:50:20+00:00

Add a protocol spec for DPLL. Add code generated from the spec. Signed-off-by: Jakub Kicinski Signed-off-by: Michal Michalik Signed-off-by: Vadim Fedorenko Signed-off-by: Arkadiusz Kubalewski Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller