diff options
| author | Marek Vasut <marex@denx.de> | 2021-01-27 12:07:56 +0100 |
|---|---|---|
| committer | Philippe Cornu <philippe.cornu@foss.st.com> | 2021-02-15 17:05:59 +0100 |
| commit | 99e360442f223dd40fc23ae07c7a263836fd27e6 (patch) | |
| tree | bb27d9d456f43008419f936c4805354c3e1defa4 /drivers/gpu | |
| parent | 0eae01bea643413758e78ca8f07be2b1ba234e36 (diff) | |
| download | linux-99e360442f223dd40fc23ae07c7a263836fd27e6.tar.bz2 | |
drm/stm: Fix bus_flags handling
The drm_display_mode_to_videomode() does not populate DISPLAY_FLAGS_DE_LOW
or DISPLAY_FLAGS_PIXDATA_NEGEDGE flags in struct videomode. Therefore, no
matter what polarity the next bridge or display might require, these flags
are never set, and thus the LTDC GCR_DEPOL and GCR_PCPOL bits are never set
and the LTDC behaves as if both DISPLAY_FLAGS_PIXDATA_POSEDGE and
DISPLAY_FLAGS_DE_HIGH were always set.
The fix for this problem is taken almost verbatim from MXSFB driver. In
case there is a bridge attached to the LTDC, the bridge might have extra
polarity requirements, so extract bus_flags from the bridge and use them
for LTDC configuration. Otherwise, extract bus_flags from the connector,
which is the display.
Fixes: b759012c5fa7 ("drm/stm: Add STM32 LTDC driver")
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Yannick Fertre <yannick.fertre@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Antonio Borneo <antonio.borneo@st.com>
Cc: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Philippe Cornu <philippe.cornu@st.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: Yannick Fertre <yannick.fertre@st.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
To: dri-devel@lists.freedesktop.org
Tested-by: Yannick Fertre <yannick.fertre@foss.st.com>
Signed-off-by: Philippe Cornu <philippe.cornu@foss.st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210127110756.125570-1-marex@denx.de
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/stm/ltdc.c | 33 |
1 files changed, 31 insertions, 2 deletions
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 7812094f93d6..6f3b523e16e8 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -525,13 +525,42 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc) { struct ltdc_device *ldev = crtc_to_ltdc(crtc); struct drm_device *ddev = crtc->dev; + struct drm_connector_list_iter iter; + struct drm_connector *connector = NULL; + struct drm_encoder *encoder = NULL; + struct drm_bridge *bridge = NULL; struct drm_display_mode *mode = &crtc->state->adjusted_mode; struct videomode vm; u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h; u32 total_width, total_height; + u32 bus_flags = 0; u32 val; int ret; + /* get encoder from crtc */ + drm_for_each_encoder(encoder, ddev) + if (encoder->crtc == crtc) + break; + + if (encoder) { + /* get bridge from encoder */ + list_for_each_entry(bridge, &encoder->bridge_chain, chain_node) + if (bridge->encoder == encoder) + break; + + /* Get the connector from encoder */ + drm_connector_list_iter_begin(ddev, &iter); + drm_for_each_connector_iter(connector, &iter) + if (connector->encoder == encoder) + break; + drm_connector_list_iter_end(&iter); + } + + if (bridge && bridge->timings) + bus_flags = bridge->timings->input_bus_flags; + else if (connector) + bus_flags = connector->display_info.bus_flags; + if (!pm_runtime_active(ddev->dev)) { ret = pm_runtime_get_sync(ddev->dev); if (ret) { @@ -567,10 +596,10 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc) if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH) val |= GCR_VSPOL; - if (vm.flags & DISPLAY_FLAGS_DE_LOW) + if (bus_flags & DRM_BUS_FLAG_DE_LOW) val |= GCR_DEPOL; - if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE) + if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE) val |= GCR_PCPOL; reg_update_bits(ldev->regs, LTDC_GCR, |