From: Jitao Shi jitao.shi@mediatek.com
[ Upstream commit cde7e2e35c2866d22a3a012e72a41052dfcc255d ]
In order to match the changes of "Use the drm_panel_bridge API", the poweron/poweroff of dsi is extracted from enable/disable and defined as new funcs (atomic_pre_enable/atomic_post_disable).
Since dsi_poweron is moved from dsi_enable to pre_enable function, in order to avoid poweron failure, the operation of dsi register fails to cause bus hang. Therefore, the protection mechanism is added to the dsi_enable function.
Fixes: 2dd8075d2185 ("drm/mediatek: mtk_dsi: Use the drm_panel_bridge API")
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/1653012007-11854-3... Signed-off-by: Jitao Shi jitao.shi@mediatek.com Signed-off-by: Xinlei Lee xinlei.lee@mediatek.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Rex-BC Chen rex-bc.chen@mediatek.com Signed-off-by: Chun-Kuang Hu chunkuang.hu@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/mediatek/mtk_dsi.c | 53 +++++++++++++++++++----------- 1 file changed, 34 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c index 6e7793f935da..966a4729bb41 100644 --- a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -691,16 +691,6 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi) if (--dsi->refcount != 0) return;
- /* - * mtk_dsi_stop() and mtk_dsi_start() is asymmetric, since - * mtk_dsi_stop() should be called after mtk_drm_crtc_atomic_disable(), - * which needs irq for vblank, and mtk_dsi_stop() will disable irq. - * mtk_dsi_start() needs to be called in mtk_output_dsi_enable(), - * after dsi is fully set. - */ - mtk_dsi_stop(dsi); - - mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500); mtk_dsi_reset_engine(dsi); mtk_dsi_lane0_ulp_mode_enter(dsi); mtk_dsi_clk_ulp_mode_enter(dsi); @@ -715,17 +705,9 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi)
static void mtk_output_dsi_enable(struct mtk_dsi *dsi) { - int ret; - if (dsi->enabled) return;
- ret = mtk_dsi_poweron(dsi); - if (ret < 0) { - DRM_ERROR("failed to power on dsi\n"); - return; - } - mtk_dsi_set_mode(dsi); mtk_dsi_clk_hs_mode(dsi, 1);
@@ -739,7 +721,16 @@ static void mtk_output_dsi_disable(struct mtk_dsi *dsi) if (!dsi->enabled) return;
- mtk_dsi_poweroff(dsi); + /* + * mtk_dsi_stop() and mtk_dsi_start() is asymmetric, since + * mtk_dsi_stop() should be called after mtk_drm_crtc_atomic_disable(), + * which needs irq for vblank, and mtk_dsi_stop() will disable irq. + * mtk_dsi_start() needs to be called in mtk_output_dsi_enable(), + * after dsi is fully set. + */ + mtk_dsi_stop(dsi); + + mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500);
dsi->enabled = false; } @@ -776,13 +767,37 @@ static void mtk_dsi_bridge_atomic_enable(struct drm_bridge *bridge, { struct mtk_dsi *dsi = bridge_to_dsi(bridge);
+ if (dsi->refcount == 0) + return; + mtk_output_dsi_enable(dsi); }
+static void mtk_dsi_bridge_atomic_pre_enable(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state) +{ + struct mtk_dsi *dsi = bridge_to_dsi(bridge); + int ret; + + ret = mtk_dsi_poweron(dsi); + if (ret < 0) + DRM_ERROR("failed to power on dsi\n"); +} + +static void mtk_dsi_bridge_atomic_post_disable(struct drm_bridge *bridge, + struct drm_bridge_state *old_bridge_state) +{ + struct mtk_dsi *dsi = bridge_to_dsi(bridge); + + mtk_dsi_poweroff(dsi); +} + static const struct drm_bridge_funcs mtk_dsi_bridge_funcs = { .attach = mtk_dsi_bridge_attach, .atomic_disable = mtk_dsi_bridge_atomic_disable, .atomic_enable = mtk_dsi_bridge_atomic_enable, + .atomic_pre_enable = mtk_dsi_bridge_atomic_pre_enable, + .atomic_post_disable = mtk_dsi_bridge_atomic_post_disable, .mode_set = mtk_dsi_bridge_mode_set, };