  The inclusive A_1,p and hadron double-spin asymmetries A_p^pi+, A_p^pi-,
A_p^K+, A_p^K- measured at COMPASS (CERN SPS) in deep-inelastic scattering of a
polarized muon beam off a polarized NH_3 solid target are presented. The
results have been obtained with the full statistics collected in 2007 for the
longitudinal target polarization. Proton asymmetries have been combined with
the published deuteron ones. An evaluation of the non-singlet spin-dependent
structure function g_1^NS(x,Q^2) and its first moment, which confirms the
validity of the Bjorken sum-rule, is presented. A LO evaluation of polarized
quark densities is also presented. The use of the proton data allows to perform
a full flavor separation and to extract individual helicity densities of u, d,
anti-u, anti-d and s quarks. All sea quark densities are found to be compatible
with zero in the full range of the measurements.
