drm/sun4i: Add LVDS support
The TCON supports the LVDS interface to output to a panel or a bridge.
Let's add support for it.
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/7fbb85f33ee1d5009fde4f0d7d236e11ca58b114.1513854122.git-series.maxime.ripard@free-electrons.com
diff --git a/drivers/gpu/drm/sun4i/sun4i_lvds.c b/drivers/gpu/drm/sun4i/sun4i_lvds.c
new file mode 100644
index 0000000..be3f14d
--- /dev/null
+++ b/drivers/gpu/drm/sun4i/sun4i_lvds.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2017 Free Electrons
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+#include <linux/clk.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+
+#include "sun4i_crtc.h"
+#include "sun4i_tcon.h"
+#include "sun4i_lvds.h"
+
+struct sun4i_lvds {
+ struct drm_connector connector;
+ struct drm_encoder encoder;
+
+ struct sun4i_tcon *tcon;
+};
+
+static inline struct sun4i_lvds *
+drm_connector_to_sun4i_lvds(struct drm_connector *connector)
+{
+ return container_of(connector, struct sun4i_lvds,
+ connector);
+}
+
+static inline struct sun4i_lvds *
+drm_encoder_to_sun4i_lvds(struct drm_encoder *encoder)
+{
+ return container_of(encoder, struct sun4i_lvds,
+ encoder);
+}
+
+static int sun4i_lvds_get_modes(struct drm_connector *connector)
+{
+ struct sun4i_lvds *lvds =
+ drm_connector_to_sun4i_lvds(connector);
+ struct sun4i_tcon *tcon = lvds->tcon;
+
+ return drm_panel_get_modes(tcon->panel);
+}
+
+static struct drm_connector_helper_funcs sun4i_lvds_con_helper_funcs = {
+ .get_modes = sun4i_lvds_get_modes,
+};
+
+static void
+sun4i_lvds_connector_destroy(struct drm_connector *connector)
+{
+ struct sun4i_lvds *lvds = drm_connector_to_sun4i_lvds(connector);
+ struct sun4i_tcon *tcon = lvds->tcon;
+
+ drm_panel_detach(tcon->panel);
+ drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs sun4i_lvds_con_funcs = {
+ .fill_modes = drm_helper_probe_single_connector_modes,
+ .destroy = sun4i_lvds_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 void sun4i_lvds_encoder_enable(struct drm_encoder *encoder)
+{
+ struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
+ struct sun4i_tcon *tcon = lvds->tcon;
+
+ DRM_DEBUG_DRIVER("Enabling LVDS output\n");
+
+ if (!IS_ERR(tcon->panel)) {
+ drm_panel_prepare(tcon->panel);
+ drm_panel_enable(tcon->panel);
+ }
+}
+
+static void sun4i_lvds_encoder_disable(struct drm_encoder *encoder)
+{
+ struct sun4i_lvds *lvds = drm_encoder_to_sun4i_lvds(encoder);
+ struct sun4i_tcon *tcon = lvds->tcon;
+
+ DRM_DEBUG_DRIVER("Disabling LVDS output\n");
+
+ if (!IS_ERR(tcon->panel)) {
+ drm_panel_disable(tcon->panel);
+ drm_panel_unprepare(tcon->panel);
+ }
+}
+
+static const struct drm_encoder_helper_funcs sun4i_lvds_enc_helper_funcs = {
+ .disable = sun4i_lvds_encoder_disable,
+ .enable = sun4i_lvds_encoder_enable,
+};
+
+static const struct drm_encoder_funcs sun4i_lvds_enc_funcs = {
+ .destroy = drm_encoder_cleanup,
+};
+
+int sun4i_lvds_init(struct drm_device *drm, struct sun4i_tcon *tcon)
+{
+ struct drm_encoder *encoder;
+ struct drm_bridge *bridge;
+ struct sun4i_lvds *lvds;
+ int ret;
+
+ lvds = devm_kzalloc(drm->dev, sizeof(*lvds), GFP_KERNEL);
+ if (!lvds)
+ return -ENOMEM;
+ lvds->tcon = tcon;
+ encoder = &lvds->encoder;
+
+ ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0,
+ &tcon->panel, &bridge);
+ if (ret) {
+ dev_info(drm->dev, "No panel or bridge found... LVDS output disabled\n");
+ return 0;
+ }
+
+ drm_encoder_helper_add(&lvds->encoder,
+ &sun4i_lvds_enc_helper_funcs);
+ ret = drm_encoder_init(drm,
+ &lvds->encoder,
+ &sun4i_lvds_enc_funcs,
+ DRM_MODE_ENCODER_LVDS,
+ NULL);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't initialise the lvds encoder\n");
+ goto err_out;
+ }
+
+ /* The LVDS encoder can only work with the TCON channel 0 */
+ lvds->encoder.possible_crtcs = BIT(drm_crtc_index(&tcon->crtc->crtc));
+
+ if (tcon->panel) {
+ drm_connector_helper_add(&lvds->connector,
+ &sun4i_lvds_con_helper_funcs);
+ ret = drm_connector_init(drm, &lvds->connector,
+ &sun4i_lvds_con_funcs,
+ DRM_MODE_CONNECTOR_LVDS);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't initialise the lvds connector\n");
+ goto err_cleanup_connector;
+ }
+
+ drm_mode_connector_attach_encoder(&lvds->connector,
+ &lvds->encoder);
+
+ ret = drm_panel_attach(tcon->panel, &lvds->connector);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't attach our panel\n");
+ goto err_cleanup_connector;
+ }
+ }
+
+ if (bridge) {
+ ret = drm_bridge_attach(encoder, bridge, NULL);
+ if (ret) {
+ dev_err(drm->dev, "Couldn't attach our bridge\n");
+ goto err_cleanup_connector;
+ }
+ }
+
+ return 0;
+
+err_cleanup_connector:
+ drm_encoder_cleanup(&lvds->encoder);
+err_out:
+ return ret;
+}
+EXPORT_SYMBOL(sun4i_lvds_init);