mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-02 18:44:56 -04:00
The frequency for an input reference is computed as: frequency = freq_base * freq_mult * freq_ratio_m / freq_ratio_n Before commit5bc02b190a("dpll: zl3073x: Cache all reference properties in zl3073x_ref"), zl3073x_dpll_input_pin_frequency_set() explicitly wrote 1 to both the REF_RATIO_M and REF_RATIO_N hardware registers whenever a new frequency was set. This ensured the FEC ratio was always reset to 1:1 alongside the new base/multiplier values. The refactoring in that commit introduced zl3073x_ref_freq_set() to update the cached ref state, but this helper only sets freq_base and freq_mult without resetting freq_ratio_m and freq_ratio_n to 1. Because zl3073x_ref_state_set() uses a compare-and-write strategy, unchanged ratio fields are never written to the hardware. If the device previously had non-unity FEC ratio values, they remain in effect after a frequency change, resulting in an incorrect computed frequency. Explicitly set freq_ratio_m and freq_ratio_n to 1 in zl3073x_ref_freq_set() to restore the original behavior. Fixes:5bc02b190a("dpll: zl3073x: Cache all reference properties in zl3073x_ref") Signed-off-by: Ivan Vecera <ivecera@redhat.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260216194007.680416-1-ivecera@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>