Re: [RFC PATCH 03/17] drm/exynos: dsi: Use the drm_panel_bridge API

On 04.07.2021 11:02, Jagan Teki wrote:

Use drm_panel_bridge to replace manual panel and bridge_chain handling code.

This makes the driver simpler to allow all components in the display pipeline to be treated as bridges by cleaning the way to generic connector handling.

Signed-off-by: Jagan Teki jagan@amarulasolutions.com

This breaks Exysos DSI driver operation (Trats board worked fine with only patches 1-2):

[    2.540066] exynos4-fb 11c00000.fimd: Adding to iommu group 0 [    2.554733] OF: graph: no port node found in /soc/fimd@11c00000 [    2.602819] [drm] Exynos DRM: using 11c00000.fimd device for DMA mapping operations [    2.609649] exynos-drm exynos-drm: bound 11c00000.fimd (ops fimd_component_ops) [    2.632558] exynos-drm exynos-drm: failed to bind 11c80000.dsi (ops exynos_dsi_component_ops): -22 [    2.642263] exynos-drm exynos-drm: master bind failed: -22 [    2.651017] exynos-drm: probe of exynos-drm failed with error -22

---

drivers/gpu/drm/exynos/exynos_drm_dsi.c | 167 ++++-------------------- 1 file changed, 23 insertions(+), 144 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c index d7d60aee465b..24f0b082ac6d 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c @@ -254,9 +254,6 @@ struct exynos_dsi_driver_data { struct exynos_dsi { struct drm_encoder encoder; struct mipi_dsi_host dsi_host;

• struct drm_connector connector;
• struct drm_panel *panel;
• struct list_head bridge_chain; struct drm_bridge bridge; struct drm_bridge *out_bridge; struct drm_device *drm;

@@ -287,7 +284,6 @@ struct exynos_dsi { };

#define host_to_dsi(host) container_of(host, struct exynos_dsi, dsi_host) -#define connector_to_dsi(c) container_of(c, struct exynos_dsi, connector)

static inline struct exynos_dsi *bridge_to_dsi(struct drm_bridge *b) { @@ -1379,7 +1375,6 @@ static void exynos_dsi_unregister_te_irq(struct exynos_dsi *dsi) static void exynos_dsi_bridge_enable(struct drm_bridge *bridge) { struct exynos_dsi *dsi = bridge_to_dsi(bridge);

• struct drm_bridge *iter; int ret;

  if (dsi->state & DSIM_STATE_ENABLED)

@@ -1393,134 +1388,51 @@ static void exynos_dsi_bridge_enable(struct drm_bridge *bridge)

dsi->state |= DSIM_STATE_ENABLED;

• if (dsi->panel) {

• ret = drm_panel_prepare(dsi->panel);
  

• if (ret < 0)
  

• 	goto err_put_sync;
  

• } else {

• list_for_each_entry_reverse(iter, &dsi->bridge_chain,
  

• 			    chain_node) {
  

• 	if (iter->funcs->pre_enable)
  

• 		iter->funcs->pre_enable(iter);
  

• }
  

• }

• exynos_dsi_set_display_mode(dsi); exynos_dsi_set_display_enable(dsi, true);

• if (dsi->panel) {

• ret = drm_panel_enable(dsi->panel);
  

• if (ret < 0)
  

• 	goto err_display_disable;
  

• } else {

• list_for_each_entry(iter, &dsi->bridge_chain, chain_node) {
  

• 	if (iter->funcs->enable)
  

• 		iter->funcs->enable(iter);
  

• }
  

• }

• dsi->state |= DSIM_STATE_VIDOUT_AVAILABLE; return;

-err_display_disable:

• exynos_dsi_set_display_enable(dsi, false);
• drm_panel_unprepare(dsi->panel);

-err_put_sync:

• dsi->state &= ~DSIM_STATE_ENABLED;

• pm_runtime_put(dsi->dev); }

  static void exynos_dsi_bridge_disable(struct drm_bridge *bridge) { struct exynos_dsi *dsi = bridge_to_dsi(bridge);

• struct drm_bridge *iter;

  if (!(dsi->state & DSIM_STATE_ENABLED)) return;

  dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;

• drm_panel_disable(dsi->panel);

• list_for_each_entry_reverse(iter, &dsi->bridge_chain, chain_node) {

• if (iter->funcs->disable)
  

• 	iter->funcs->disable(iter);
  

• }

• exynos_dsi_set_display_enable(dsi, false);

• drm_panel_unprepare(dsi->panel);

• list_for_each_entry(iter, &dsi->bridge_chain, chain_node) {

• if (iter->funcs->post_disable)
  

• 	iter->funcs->post_disable(iter);
  

• }

  dsi->state &= ~DSIM_STATE_ENABLED; pm_runtime_put_sync(dsi->dev); }

-static enum drm_connector_status -exynos_dsi_detect(struct drm_connector *connector, bool force) -{

• return connector->status;

-}

-static void exynos_dsi_connector_destroy(struct drm_connector *connector) +static int exynos_dsi_panel_or_bridge(struct exynos_dsi *dsi,

• 		      struct device_node *node)
  

  {

• drm_connector_unregister(connector);
• drm_connector_cleanup(connector);
• connector->dev = NULL;

-}

-static const struct drm_connector_funcs exynos_dsi_connector_funcs = {

• .detect = exynos_dsi_detect,
• .fill_modes = drm_helper_probe_single_connector_modes,
• .destroy = exynos_dsi_connector_destroy,
• .reset = drm_atomic_helper_connector_reset,
• .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
• .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,

-};

-static int exynos_dsi_get_modes(struct drm_connector *connector) -{

• struct exynos_dsi *dsi = connector_to_dsi(connector);
• if (dsi->panel)

• return drm_panel_get_modes(dsi->panel, connector);
  

• return 0;

-}

• struct drm_bridge *panel_bridge;
• struct drm_panel *panel;

-static const struct drm_connector_helper_funcs exynos_dsi_connector_helper_funcs = {

• .get_modes = exynos_dsi_get_modes,

-};

• panel_bridge = of_drm_find_bridge(node);
• if (!panel_bridge) {

• panel = of_drm_find_panel(node);
  

• if (!IS_ERR(panel)) {
  

• 	panel_bridge = drm_panel_bridge_add(panel);
  

• 	if (IS_ERR(panel_bridge))
  

• 		return PTR_ERR(panel_bridge);
  

• }
  

• }

-static int exynos_dsi_create_connector(struct exynos_dsi *dsi,

• 		       struct drm_device *drm)
  

-{

• struct drm_encoder *encoder = &dsi->encoder;
• struct drm_connector *connector = &dsi->connector;
• int ret;

• of_node_put(node);

• connector->polled = DRM_CONNECTOR_POLL_HPD;

• dsi->out_bridge = panel_bridge;

• ret = drm_connector_init(drm, connector, &exynos_dsi_connector_funcs,

• 		 DRM_MODE_CONNECTOR_DSI);
  

• if (ret) {

• DRM_DEV_ERROR(dsi->dev,
  

• 	      "Failed to initialize connector with drm\n");
  

• return ret;
  

• }

• if (!dsi->out_bridge)

• return -EPROBE_DEFER;
  
  

• connector->status = connector_status_disconnected;
• drm_connector_helper_add(connector, &exynos_dsi_connector_helper_funcs);
• drm_connector_attach_encoder(connector, encoder);
• if (!drm->registered)

• return 0;
  

• connector->funcs->reset(connector);
• drm_connector_register(connector); return 0; }

@@ -1531,7 +1443,8 @@ static int exynos_dsi_bridge_attach(struct drm_bridge *bridge,

dsi->drm = bridge->dev;

• return 0;

• return drm_bridge_attach(bridge->encoder, dsi->out_bridge, bridge,

• 		 flags);
  

  }

  static const struct drm_bridge_funcs exynos_dsi_bridge_funcs = {

@@ -1546,32 +1459,12 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host, struct mipi_dsi_device *device) { struct exynos_dsi *dsi = host_to_dsi(host);

• struct drm_encoder *encoder = &dsi->encoder; struct drm_device *drm = dsi->drm;
• struct drm_bridge *out_bridge;
• out_bridge = of_drm_find_bridge(device->dev.of_node);
• if (out_bridge) {

• drm_bridge_attach(encoder, out_bridge, NULL, 0);
  

• dsi->out_bridge = out_bridge;
  

• list_splice_init(&encoder->bridge_chain, &dsi->bridge_chain);
  

• } else {

• int ret = exynos_dsi_create_connector(dsi, drm);
  

• if (ret) {
  

• 	DRM_DEV_ERROR(dsi->dev,
  

• 		      "failed to create connector ret = %d\n",
  

• 		      ret);
  

• 	drm_encoder_cleanup(encoder);
  

• 	return ret;
  

• }
  

• int ret;

• dsi->panel = of_drm_find_panel(device->dev.of_node);
  

• if (IS_ERR(dsi->panel))
  

• 	dsi->panel = NULL;
  

• else
  

• 	dsi->connector.status = connector_status_connected;
  

• }

• ret = exynos_dsi_panel_or_bridge(dsi, device->dev.of_node);

• if (ret)

• return ret;
  
  

  /*

  • This is a temporary solution and should be made by more generic way.

@@ -1607,19 +1500,6 @@ static int exynos_dsi_host_detach(struct mipi_dsi_host *host, struct exynos_dsi *dsi = host_to_dsi(host); struct drm_device *drm = dsi->drm;

• if (dsi->panel) {

• mutex_lock(&drm->mode_config.mutex);
  

• exynos_dsi_bridge_disable(&dsi->bridge);
  

• dsi->panel = NULL;
  

• dsi->connector.status = connector_status_disconnected;
  

• mutex_unlock(&drm->mode_config.mutex);
  

• } else {

• if (dsi->out_bridge->funcs->detach)
  

• 	dsi->out_bridge->funcs->detach(dsi->out_bridge);
  

• dsi->out_bridge = NULL;
  

• INIT_LIST_HEAD(&dsi->bridge_chain);
  

• }
• if (drm->mode_config.poll_enabled) drm_kms_helper_hotplug_event(drm);

@@ -1770,7 +1650,6 @@ static int exynos_dsi_probe(struct platform_device *pdev) init_completion(&dsi->completed); spin_lock_init(&dsi->transfer_lock); INIT_LIST_HEAD(&dsi->transfer_list);

• INIT_LIST_HEAD(&dsi->bridge_chain);

  dsi->dsi_host.ops = &exynos_dsi_ops; dsi->dsi_host.dev = dev;

Best regards