6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
[ Upstream commit 5855d422a6f250f3518f43b49092c8e87a5e42be ]
Due to the initial confusion about MIPI_DSI_MODE_EOT_PACKET, properly
renamed to MIPI_DSI_MODE_NO_EOT_PACKET, reflecting its actual meaning,
both the DSI_TXRX_CON register setting for bit (HSTX_)DIS_EOT and the
later calculation for horizontal sync-active (HSA), back (HBP) and
front (HFP) porches got incorrect due to the logic being inverted.
This means that a number of settings were wrong because....:
- DSI_TXRX_CON register setting: bit (HSTX_)DIS_EOT should be
set in order to disable the End of Transmission packet;
- Horizontal Sync and Back/Front porches: The delta used to
calculate all of HSA, HBP and HFP should account for the
additional EOT packet.
Before this change...
- Bit (HSTX_)DIS_EOT was being set when EOT packet was enabled;
- For HSA/HBP/HFP delta... all three were wrong, as words were
added when EOT disabled, instead of when EOT packet enabled!
Invert the logic around flag MIPI_DSI_MODE_NO_EOT_PACKET in the
MediaTek DSI driver to fix the aforementioned issues.
Fixes: 8b2b99fd7931 ("drm/mediatek: dsi: Fine tune the line time caused by EOTp")
Fixes: c87d1c4b5b9a ("drm/mediatek: dsi: Use symbolized register definition")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Reviewed-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx>
Tested-by: Michael Walle <mwalle@xxxxxxxxxx>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20230523104234.7849-1-angelogioacchino.delregno@xxxxxxxxxxxxx/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_dsi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index 9e1363c9fcdb4..3e74c7c1b89fa 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -406,7 +406,7 @@ static void mtk_dsi_rxtx_control(struct mtk_dsi *dsi)
if (dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
tmp_reg |= HSTX_CKLP_EN;
- if (!(dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET))
+ if (dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)
tmp_reg |= DIS_EOT;
writel(tmp_reg, dsi->regs + DSI_TXRX_CTRL);
@@ -483,7 +483,7 @@ static void mtk_dsi_config_vdo_timing(struct mtk_dsi *dsi)
timing->da_hs_zero + timing->da_hs_exit + 3;
delta = dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST ? 18 : 12;
- delta += dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET ? 2 : 0;
+ delta += dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET ? 0 : 2;
horizontal_frontporch_byte = vm->hfront_porch * dsi_tmp_buf_bpp;
horizontal_front_back_byte = horizontal_frontporch_byte + horizontal_backporch_byte;
--
2.42.0
