[PATCH v7] rockchip/drm: vop2: add support for gamma LUT

[Andy Yan]

Hi Piotr,

At 2024-12-05 16:54:09, "Heiko Stübner" <heiko at sntech.de> wrote:
>Hi Piotr,
>
>Am Mittwoch, 4. Dezember 2024, 16:45:21 CET schrieb Piotr Zalewski:
>> I just noticed that after coming out of suspend gamma LUT is lost and must
>> be rewritten by userspace.
>> 
>> So I guess it will be needed to save LUT to a buffer and rewrite it after
>> going out of suspend during modeset?
>
>Most likely ... the old vop does this already too, so I guess you can
>get inspiration from there. (gamma_set call in vop_crtc_atomic_enable())

I guess it returned because crtc_state->color_mgmt_changed is false when called from 
vop2_crtc_atomic_enable from s2r.


static void vop2_crtc_atomic_try_set_gamma(struct vop2 *vop2,
                                           struct vop2_video_port *vp,
                                           struct drm_crtc *crtc,
                                           struct drm_crtc_state *crtc_state)
{
        if (!vop2->lut_regs || !crtc_state->color_mgmt_changed)
                return;

        if (!crtc_state->gamma_lut) {
                vop2_vp_dsp_lut_disable(vp);
                return;
        }

        if (vop2_supports_seamless_gamma_lut_update(vop2))
                vop2_crtc_atomic_set_gamma_seamless(vop2, vp, crtc);
        else
                vop2_crtc_atomic_set_gamma_rk356x(vop2, vp, crtc);
}
>
>> I checked the patch isn't yet in the "official" linux-next.
>
>The patch is in drm-misc-next:
>https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/4f537776340dab2b680a4d8554567f6884240d0b
>
>so should turn up in linux-next at some point. This also means, please
>provide a follow-up patch for the suspend handling.
>
>Thanks a lot
>Heiko
>