[PATCH v2 7/8] imx-drm: ipuv3-crtc: Change display enable/disable order

From: Philipp Zabel
Date: Mon Apr 14 2014 - 17:56:59 EST


Now that ipu_dc_disable_channel correctly waits for the channel to finish,
we can reorder the enable/disable order to first stop the DC and DI and
only then disable the IDMAC. Enabling is done the other way around: IDMAC
first, then DC, then DI.

This avoids an issue where sometimes the channel would not correctly start,
leading to non-working LVDS displays.

Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
---
drivers/staging/imx-drm/ipuv3-crtc.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/imx-drm/ipuv3-crtc.c b/drivers/staging/imx-drm/ipuv3-crtc.c
index c48f640..c771ac1 100644
--- a/drivers/staging/imx-drm/ipuv3-crtc.c
+++ b/drivers/staging/imx-drm/ipuv3-crtc.c
@@ -63,9 +63,11 @@ static void ipu_fb_enable(struct ipu_crtc *ipu_crtc)
if (ipu_crtc->enabled)
return;

- ipu_di_enable(ipu_crtc->di);
- ipu_dc_enable_channel(ipu_crtc->dc);
+ /* TODO: Enable DC module here, right now it is never disabled */
ipu_plane_enable(ipu_crtc->plane[0]);
+ /* Start DC channel and DI after IDMAC */
+ ipu_dc_enable_channel(ipu_crtc->dc);
+ ipu_di_enable(ipu_crtc->di);

ipu_crtc->enabled = 1;
}
@@ -75,9 +77,11 @@ static void ipu_fb_disable(struct ipu_crtc *ipu_crtc)
if (!ipu_crtc->enabled)
return;

- ipu_plane_disable(ipu_crtc->plane[0]);
+ /* Stop DC channel and DI before IDMAC */
ipu_dc_disable_channel(ipu_crtc->dc);
ipu_di_disable(ipu_crtc->di);
+ ipu_plane_disable(ipu_crtc->plane[0]);
+ /* TODO: Disable DC module here */

ipu_crtc->enabled = 0;
}
--
1.9.1

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