[PATCH v5 3/7] drm: sun4i: dsi: Convert to bridge driver
Jagan Teki
jagan at amarulasolutions.com
Sun Nov 21 22:52:19 PST 2021
Some display panels would come up with a non-DSI output, those
can have an option to connect the DSI host by means of interface
bridge converter.
This DSI to non-DSI interface bridge converter would requires
DSI Host to handle drm bridge functionalities in order to DSI
Host to Interface bridge.
This patch convert the existing to a drm bridge driver with a
built-in encoder support for compatibility with existing
component drivers.
Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
Changes for v5:
- add atomic APIs
- find host and device variant DSI devices.
Changes for v4, v3:
- none
drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 112 ++++++++++++++++++++-----
drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h | 7 ++
2 files changed, 96 insertions(+), 23 deletions(-)
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 43d9c9e5198d..a6a272b55f77 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -21,6 +21,7 @@
#include <drm/drm_atomic_helper.h>
#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_of.h>
#include <drm/drm_panel.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
@@ -713,10 +714,11 @@ static int sun6i_dsi_start(struct sun6i_dsi *dsi,
return 0;
}
-static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
+static void sun6i_dsi_bridge_atomic_enable(struct drm_bridge *bridge,
+ struct drm_bridge_state *old_bridge_state)
{
- struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
- struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
+ struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
+ struct drm_display_mode *mode = &bridge->encoder->crtc->state->adjusted_mode;
struct mipi_dsi_device *device = dsi->device;
union phy_configure_opts opts = { };
struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy;
@@ -772,6 +774,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
if (dsi->panel)
drm_panel_prepare(dsi->panel);
+ if (dsi->next_bridge)
+ dsi->next_bridge->funcs->atomic_pre_enable(dsi->next_bridge, old_bridge_state);
+
/*
* FIXME: This should be moved after the switch to HS mode.
*
@@ -787,6 +792,9 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
if (dsi->panel)
drm_panel_enable(dsi->panel);
+ if (dsi->next_bridge)
+ dsi->next_bridge->funcs->atomic_enable(dsi->next_bridge, old_bridge_state);
+
sun6i_dsi_start(dsi, DSI_START_HSC);
udelay(1000);
@@ -794,15 +802,19 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
sun6i_dsi_start(dsi, DSI_START_HSD);
}
-static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder)
+static void sun6i_dsi_bridge_atomic_disable(struct drm_bridge *bridge,
+ struct drm_bridge_state *old_bridge_state)
{
- struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
+ struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
DRM_DEBUG_DRIVER("Disabling DSI output\n");
if (dsi->panel) {
drm_panel_disable(dsi->panel);
drm_panel_unprepare(dsi->panel);
+ } else if (dsi->next_bridge) {
+ dsi->next_bridge->funcs->atomic_disable(dsi->next_bridge, old_bridge_state);
+ dsi->next_bridge->funcs->atomic_post_disable(dsi->next_bridge, old_bridge_state);
}
phy_power_off(dsi->dphy);
@@ -842,9 +854,25 @@ static const struct drm_connector_funcs sun6i_dsi_connector_funcs = {
.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};
-static const struct drm_encoder_helper_funcs sun6i_dsi_enc_helper_funcs = {
- .disable = sun6i_dsi_encoder_disable,
- .enable = sun6i_dsi_encoder_enable,
+static int sun6i_dsi_bridge_attach(struct drm_bridge *bridge,
+ enum drm_bridge_attach_flags flags)
+{
+ struct sun6i_dsi *dsi = bridge_to_sun6i_dsi(bridge);
+
+ if (dsi->next_bridge)
+ return drm_bridge_attach(bridge->encoder, dsi->next_bridge,
+ NULL, 0);
+
+ return 0;
+}
+
+static const struct drm_bridge_funcs sun6i_dsi_bridge_funcs = {
+ .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
+ .atomic_reset = drm_atomic_helper_bridge_reset,
+ .atomic_enable = sun6i_dsi_bridge_atomic_enable,
+ .atomic_disable = sun6i_dsi_bridge_atomic_disable,
+ .attach = sun6i_dsi_bridge_attach,
};
static u32 sun6i_dsi_dcs_build_pkt_hdr(struct sun6i_dsi *dsi,
@@ -966,8 +994,6 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
struct sun6i_dsi *dsi = dev_get_drvdata(dev);
int ret;
- drm_encoder_helper_add(&dsi->encoder,
- &sun6i_dsi_enc_helper_funcs);
ret = drm_simple_encoder_init(drm, &dsi->encoder,
DRM_MODE_ENCODER_DSI);
if (ret) {
@@ -976,18 +1002,26 @@ static int sun6i_dsi_bind(struct device *dev, struct device *master,
}
dsi->encoder.possible_crtcs = BIT(0);
- drm_connector_helper_add(&dsi->connector,
- &sun6i_dsi_connector_helper_funcs);
- ret = drm_connector_init(drm, &dsi->connector,
- &sun6i_dsi_connector_funcs,
- DRM_MODE_CONNECTOR_DSI);
+ ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, 0);
if (ret) {
- dev_err(dsi->dev,
- "Couldn't initialise the DSI connector\n");
+ dev_err(dsi->dev, "Couldn't attach drm bridge\n");
goto err_cleanup_connector;
}
- drm_connector_attach_encoder(&dsi->connector, &dsi->encoder);
+ if (dsi->panel) {
+ drm_connector_helper_add(&dsi->connector,
+ &sun6i_dsi_connector_helper_funcs);
+ ret = drm_connector_init(drm, &dsi->connector,
+ &sun6i_dsi_connector_funcs,
+ DRM_MODE_CONNECTOR_DSI);
+ if (ret) {
+ dev_err(dsi->dev,
+ "Couldn't initialise the DSI connector\n");
+ goto err_cleanup_connector;
+ }
+
+ drm_connector_attach_encoder(&dsi->connector, &dsi->encoder);
+ }
return 0;
@@ -1013,16 +1047,46 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host,
struct mipi_dsi_device *device)
{
struct sun6i_dsi *dsi = host_to_sun6i_dsi(host);
- struct drm_panel *panel = of_drm_find_panel(device->dev.of_node);
+ struct device_node *remote = device->dev.of_node;
int ret;
- if (IS_ERR(panel))
- return PTR_ERR(panel);
+ if (!of_device_is_available(remote)) {
+ /**
+ * I2C interfaced DSI bridges will register DSI host on the
+ * bridge drivers instead of conventional device.
+ *
+ * Those are probed via host of_node instead of device of_node.
+ */
+ remote = of_graph_get_remote_node(host->dev->of_node, 0, 0);
+ if (!remote)
+ return -ENODEV;
+ }
+
+ dsi->panel = of_drm_find_panel(remote);
+ if (IS_ERR(dsi->panel)) {
+ dsi->panel = NULL;
+
+ dsi->next_bridge = of_drm_find_bridge(remote);
+ if (IS_ERR(dsi->next_bridge)) {
+ dev_err(dsi->dev, "failed to find bridge\n");
+ return PTR_ERR(dsi->next_bridge);
+ }
+ } else {
+ dsi->next_bridge = NULL;
+ }
+
+ of_node_put(remote);
- dsi->panel = panel;
dsi->device = device;
- dev_info(host->dev, "Attached device %s\n", device->name);
+ dev_info(host->dev, "Attached %s %s\n",
+ device->name, dsi->panel ? "panel" : "bridge");
+
+ dsi->bridge.funcs = &sun6i_dsi_bridge_funcs;
+ dsi->bridge.of_node = dsi->dev->of_node;
+ dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;
+
+ drm_bridge_add(&dsi->bridge);
ret = component_add(dsi->dev, &sun6i_dsi_ops);
if (ret) {
@@ -1040,9 +1104,11 @@ static int sun6i_dsi_detach(struct mipi_dsi_host *host,
struct sun6i_dsi *dsi = host_to_sun6i_dsi(host);
dsi->panel = NULL;
+ dsi->next_bridge = NULL;
dsi->device = NULL;
component_del(dsi->dev, &sun6i_dsi_ops);
+ drm_bridge_remove(&dsi->bridge);
return 0;
}
diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
index 61e88ea6044d..d269304691c9 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.h
@@ -16,6 +16,7 @@
#define SUN6I_DSI_TCON_DIV 4
struct sun6i_dsi {
+ struct drm_bridge bridge;
struct drm_connector connector;
struct drm_encoder encoder;
struct mipi_dsi_host host;
@@ -30,6 +31,7 @@ struct sun6i_dsi {
struct device *dev;
struct mipi_dsi_device *device;
struct drm_panel *panel;
+ struct drm_bridge *next_bridge;
};
static inline struct sun6i_dsi *host_to_sun6i_dsi(struct mipi_dsi_host *host)
@@ -37,6 +39,11 @@ static inline struct sun6i_dsi *host_to_sun6i_dsi(struct mipi_dsi_host *host)
return container_of(host, struct sun6i_dsi, host);
};
+static inline struct sun6i_dsi *bridge_to_sun6i_dsi(struct drm_bridge *bridge)
+{
+ return container_of(bridge, struct sun6i_dsi, bridge);
+}
+
static inline struct sun6i_dsi *connector_to_sun6i_dsi(struct drm_connector *connector)
{
return container_of(connector, struct sun6i_dsi, connector);
--
2.25.1
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