Re: [RFC PATCH 01/17] drm/exynos: dsi: Convert to bridge driver

Hi Jagan,

See a few comments below.

Sam

On Sun, Jul 04, 2021 at 02:32:14PM +0530, Jagan Teki wrote:

DRM bridge drivers have built-in handling of treating all display pipeline components as bridges.

Convert exynos_drm_dsi to a bridge driver with built-in encoder support for compatibility with existing component drivers.

This keeps switching the driver into the bridge in a more feasible manner.

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

drivers/gpu/drm/exynos/exynos_drm_dsi.c | 57 +++++++++++++++++-------- 1 file changed, 39 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c index 1d777d8c1a83..90d2ce2c3055 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c @@ -257,6 +257,7 @@ struct exynos_dsi { struct drm_connector connector; struct drm_panel *panel; struct list_head bridge_chain;

• struct drm_bridge bridge; struct drm_bridge *out_bridge; struct device *dev;

@@ -287,9 +288,9 @@ 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 *encoder_to_dsi(struct drm_encoder *e) +static inline struct exynos_dsi *bridge_to_dsi(struct drm_bridge *b) {

• return container_of(e, struct exynos_dsi, encoder);

• return container_of(b, struct exynos_dsi, bridge);

}

enum reg_idx { @@ -1374,9 +1375,9 @@ static void exynos_dsi_unregister_te_irq(struct exynos_dsi *dsi) } }

-static void exynos_dsi_enable(struct drm_encoder *encoder) +static void exynos_dsi_bridge_enable(struct drm_bridge *bridge) {

• struct exynos_dsi *dsi = encoder_to_dsi(encoder);

• struct exynos_dsi *dsi = bridge_to_dsi(bridge); struct drm_bridge *iter; int ret;

@@ -1429,9 +1430,9 @@ static void exynos_dsi_enable(struct drm_encoder *encoder) pm_runtime_put(dsi->dev); }

-static void exynos_dsi_disable(struct drm_encoder *encoder) +static void exynos_dsi_bridge_disable(struct drm_bridge *bridge) {

• struct exynos_dsi *dsi = encoder_to_dsi(encoder);

• struct exynos_dsi *dsi = bridge_to_dsi(bridge); struct drm_bridge *iter;

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

@@ -1494,9 +1495,9 @@ static const struct drm_connector_helper_funcs exynos_dsi_connector_helper_funcs .get_modes = exynos_dsi_get_modes, };

-static int exynos_dsi_create_connector(struct drm_encoder *encoder) +static int exynos_dsi_create_connector(struct exynos_dsi *dsi) {

• struct exynos_dsi *dsi = encoder_to_dsi(encoder);

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

@@ -1522,9 +1523,16 @@ static int exynos_dsi_create_connector(struct drm_encoder *encoder) return 0; }

-static const struct drm_encoder_helper_funcs exynos_dsi_encoder_helper_funcs = {

• .enable = exynos_dsi_enable,
• .disable = exynos_dsi_disable,

+static int exynos_dsi_bridge_attach(struct drm_bridge *bridge,

• 		    enum drm_bridge_attach_flags flags)
  

+{

• return 0;

+}

+static const struct drm_bridge_funcs exynos_dsi_bridge_funcs = {

• .enable = exynos_dsi_bridge_enable,
• .disable = exynos_dsi_bridge_disable,
• .attach = exynos_dsi_bridge_attach,

};

For new bridge drivers please use atomic_{enable,disable}. The non-atomic variants are deprecated and it is now also documneted. It was not documented when you wrote this patch!

Sam

MODULE_DEVICE_TABLE(of, exynos_dsi_of_match); @@ -1543,7 +1551,7 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host, dsi->out_bridge = out_bridge; list_splice_init(&encoder->bridge_chain, &dsi->bridge_chain); } else {

• int ret = exynos_dsi_create_connector(encoder);
  

• int ret = exynos_dsi_create_connector(dsi);
  
  

  if (ret) { DRM_DEV_ERROR(dsi->dev,

@@ -1596,7 +1604,7 @@ static int exynos_dsi_host_detach(struct mipi_dsi_host *host,

if (dsi->panel) { mutex_lock(&drm->mode_config.mutex);

• exynos_dsi_disable(&dsi->encoder);
  

• exynos_dsi_bridge_disable(&dsi->bridge);
  

  dsi->panel = NULL; dsi->connector.status = connector_status_disconnected; mutex_unlock(&drm->mode_config.mutex);

@@ -1702,12 +1710,16 @@ static int exynos_dsi_bind(struct device *dev, struct device *master,

drm_simple_encoder_init(drm_dev, encoder, DRM_MODE_ENCODER_TMDS);

• drm_encoder_helper_add(encoder, &exynos_dsi_encoder_helper_funcs);
• ret = exynos_drm_set_possible_crtcs(encoder, EXYNOS_DISPLAY_TYPE_LCD); if (ret < 0) return ret;

• ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, 0);

I assume a later patch will move connector creation to the display driver.

• if (ret) {

• drm_encoder_cleanup(&dsi->encoder);
  

• return ret;
  

• }
• in_bridge_node = of_graph_get_remote_node(dev->of_node, DSI_PORT_IN, 0); if (in_bridge_node) { in_bridge = of_drm_find_bridge(in_bridge_node);

@@ -1723,10 +1735,9 @@ static void exynos_dsi_unbind(struct device *dev, struct device *master, void *data) { struct exynos_dsi *dsi = dev_get_drvdata(dev);

• struct drm_encoder *encoder = &dsi->encoder;
• exynos_dsi_disable(encoder);

• exynos_dsi_bridge_disable(&dsi->bridge);
• drm_encoder_cleanup(&dsi->encoder); mipi_dsi_host_unregister(&dsi->dsi_host);

}

@@ -1821,6 +1832,12 @@ static int exynos_dsi_probe(struct platform_device *pdev)

pm_runtime_enable(dev);

• dsi->bridge.funcs = &exynos_dsi_bridge_funcs;
• dsi->bridge.of_node = dev->of_node;
• dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;
• drm_bridge_add(&dsi->bridge);
• ret = component_add(dev, &exynos_dsi_component_ops); if (ret) goto err_disable_runtime;

@@ -1835,6 +1852,10 @@ static int exynos_dsi_probe(struct platform_device *pdev)

static int exynos_dsi_remove(struct platform_device *pdev) {

• struct exynos_dsi *dsi = platform_get_drvdata(pdev);

• drm_bridge_remove(&dsi->bridge);

• pm_runtime_disable(&pdev->dev);

  component_del(&pdev->dev, &exynos_dsi_component_ops);

-- 2.25.1