From 52044fb2abe8d3891e3ede7330097cf4c4c12cb5 Mon Sep 17 00:00:00 2001 From: Pin-yen Lin Date: Tue, 9 Jan 2024 20:04:57 +0800 Subject: [PATCH] drm/bridge: parade-ps8640: Ensure bridge is suspended in .post_disable() [ Upstream commit 26db46bc9c675e43230cc6accd110110a7654299 ] The ps8640 bridge seems to expect everything to be power cycled at the disable process, but sometimes ps8640_aux_transfer() holds the runtime PM reference and prevents the bridge from suspend. Prevent that by introducing a mutex lock between ps8640_aux_transfer() and .post_disable() to make sure the bridge is really powered off. Fixes: 826cff3f7ebb ("drm/bridge: parade-ps8640: Enable runtime power management") Signed-off-by: Pin-yen Lin Reviewed-by: Douglas Anderson Signed-off-by: Douglas Anderson Link: https://patchwork.freedesktop.org/patch/msgid/20240109120528.1292601-1-treapking@chromium.org Signed-off-by: Sasha Levin --- drivers/gpu/drm/bridge/parade-ps8640.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c index fb5e9ae..166bfc7 100644 --- a/drivers/gpu/drm/bridge/parade-ps8640.c +++ b/drivers/gpu/drm/bridge/parade-ps8640.c @@ -107,6 +107,7 @@ struct ps8640 { struct device_link *link; bool pre_enabled; bool need_post_hpd_delay; + struct mutex aux_lock; }; static const struct regmap_config ps8640_regmap_config[] = { @@ -345,6 +346,7 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux, struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev; int ret; + mutex_lock(&ps_bridge->aux_lock); pm_runtime_get_sync(dev); ret = _ps8640_wait_hpd_asserted(ps_bridge, 200 * 1000); if (ret) { @@ -354,6 +356,7 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux, ret = ps8640_aux_transfer_msg(aux, msg); pm_runtime_mark_last_busy(dev); pm_runtime_put_autosuspend(dev); + mutex_unlock(&ps_bridge->aux_lock); return ret; } @@ -475,7 +478,18 @@ static void ps8640_atomic_post_disable(struct drm_bridge *bridge, ps_bridge->pre_enabled = false; ps8640_bridge_vdo_control(ps_bridge, DISABLE); + + /* + * The bridge seems to expect everything to be power cycled at the + * disable process, so grab a lock here to make sure + * ps8640_aux_transfer() is not holding a runtime PM reference and + * preventing the bridge from suspend. + */ + mutex_lock(&ps_bridge->aux_lock); + pm_runtime_put_sync_suspend(&ps_bridge->page[PAGE0_DP_CNTL]->dev); + + mutex_unlock(&ps_bridge->aux_lock); } static int ps8640_bridge_attach(struct drm_bridge *bridge, @@ -624,6 +638,8 @@ static int ps8640_probe(struct i2c_client *client) if (!ps_bridge) return -ENOMEM; + mutex_init(&ps_bridge->aux_lock); + ps_bridge->supplies[0].supply = "vdd12"; ps_bridge->supplies[1].supply = "vdd33"; ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ps_bridge->supplies), -- 2.7.4