[PATCH 2/5] drm/imx: track flip state explicitly

[Lucas Stach]

Start tracking the flip state explicitly, as opposed to inferring
it from the presence if a new FB. This is a preparatory step to
introduce an new immediate state, where we can wait for a fence to
signal.

Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
---
 drivers/gpu/drm/imx/ipuv3-crtc.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/imx/ipuv3-crtc.c b/drivers/gpu/drm/imx/ipuv3-crtc.c
index a78727d9683b..55619c3de069 100644
--- a/drivers/gpu/drm/imx/ipuv3-crtc.c
+++ b/drivers/gpu/drm/imx/ipuv3-crtc.c
@@ -31,6 +31,11 @@

 #define DRIVER_DESC            "i.MX IPUv3 Graphics"

+enum ipu_flip_status {
+       IPU_FLIP_NONE,
+       IPU_FLIP_PENDING,
+};
+
 struct ipu_crtc {
        struct device           *dev;
        struct drm_crtc         base;
@@ -42,8 +47,8 @@ struct ipu_crtc {
        struct ipu_dc           *dc;
        struct ipu_di           *di;
        int                     enabled;
+       enum ipu_flip_status    flip_state;
        struct drm_pending_vblank_event *page_flip_event;
-       struct drm_framebuffer  *newfb;
        int                     irq;
        u32                     bus_format;
        int                     di_hsync_pin;
@@ -112,7 +117,7 @@ static int ipu_page_flip(struct drm_crtc *crtc,
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);
        int ret;

-       if (ipu_crtc->newfb)
+       if (ipu_crtc->flip_state != IPU_FLIP_NONE)
                return -EBUSY;

        ret = imx_drm_crtc_vblank_get(ipu_crtc->imx_crtc);
@@ -123,8 +128,8 @@ static int ipu_page_flip(struct drm_crtc *crtc,
                return ret;
        }

-       ipu_crtc->newfb = fb;
        ipu_crtc->page_flip_event = event;
+       ipu_crtc->flip_state = IPU_FLIP_PENDING;

        return 0;
 }
@@ -227,13 +232,13 @@ static irqreturn_t ipu_irq_handler(int irq, void *dev_id)

        imx_drm_handle_vblank(ipu_crtc->imx_crtc);

-       if (ipu_crtc->newfb) {
+       if (ipu_crtc->flip_state == IPU_FLIP_PENDING) {
                struct ipu_plane *plane = ipu_crtc->plane[0];

-               ipu_crtc->newfb = NULL;
                ipu_plane_set_base(plane, ipu_crtc->base.primary->fb,
                                   plane->x, plane->y);
                ipu_crtc_handle_pageflip(ipu_crtc);
+               ipu_crtc->flip_state = IPU_FLIP_NONE;
        }

        return IRQ_HANDLED;
-- 
2.7.0.rc3