5.15-stable review patch. If anyone has any objections, please let me know.
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From: Dmitry Osipenko digetx@gmail.com
[ Upstream commit fbc5a90e82c1131869e76ce5b082693b8a75c121 ]
Non-continuous clock mode doesn't work because driver doesn't support it properly. The bridge driver programs wrong bitfields that are required by the non-continuous mode (BTACNTRL1 register bitfields are swapped in the code), but fixing them doesn't help.
Display panel of ASUS Transformer TF700T tablet supports non-continuous mode and display doesn't work at all using that mode. There are no device-trees that are actively using this DSI bridge in upstream yet, so clearly the broken mode wasn't ever tested properly. It's a bit too difficult to get LP mode working, hence let's disable the offending mode for now and fall back to continuous mode.
Tested-by: Andreas Westman Dorcsak hedmoo@yahoo.com # Asus TF700T Tested-by: Maxim Schwalm maxim.schwalm@gmail.com #TF700T Signed-off-by: Dmitry Osipenko digetx@gmail.com Reviewed-by: Robert Foss robert.foss@linaro.org Signed-off-by: Robert Foss robert.foss@linaro.org Link: https://patchwork.freedesktop.org/patch/msgid/20211002233447.1105-5-digetx@g... Stable-dep-of: 66962d5c3c51 ("drm/bridge: tc358768: Fix bit updates") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/bridge/tc358768.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c index da37dfd81a6fb..1e5304274ce20 100644 --- a/drivers/gpu/drm/bridge/tc358768.c +++ b/drivers/gpu/drm/bridge/tc358768.c @@ -637,6 +637,7 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) { struct tc358768_priv *priv = bridge_to_tc358768(bridge); struct mipi_dsi_device *dsi_dev = priv->output.dev; + unsigned long mode_flags = dsi_dev->mode_flags; u32 val, val2, lptxcnt, hact, data_type; s32 raw_val; const struct drm_display_mode *mode; @@ -644,6 +645,11 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) u32 dsiclk, dsibclk; int ret, i;
+ if (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) { + dev_warn_once(priv->dev, "Non-continuous mode unimplemented, falling back to continuous\n"); + mode_flags &= ~MIPI_DSI_CLOCK_NON_CONTINUOUS; + } + tc358768_hw_enable(priv);
ret = tc358768_sw_reset(priv); @@ -779,7 +785,7 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge) val |= BIT(i + 1); tc358768_write(priv, TC358768_HSTXVREGEN, val);
- if (!(dsi_dev->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)) + if (!(mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)) tc358768_write(priv, TC358768_TXOPTIONCNTRL, 0x1);
/* TXTAGOCNT[26:16] RXTASURECNT[10:0] */ @@ -836,7 +842,7 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
val |= TC358768_DSI_CONTROL_TXMD;
- if (!(dsi_dev->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)) + if (!(mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)) val |= TC358768_DSI_CONTROL_HSCKMD;
if (dsi_dev->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET)