6.6-stable review patch. If anyone has any objections, please let me know.
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From: Pin-yen Lin treapking@chromium.org
[ 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 treapking@chromium.org Reviewed-by: Douglas Anderson dianders@chromium.org Signed-off-by: Douglas Anderson dianders@chromium.org Link: https://patchwork.freedesktop.org/patch/msgid/20240109120528.1292601-1-treap... Signed-off-by: Sasha Levin sashal@kernel.org --- 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 fb5e9ae9ad81..166bfc725ef4 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),