drm/msm: Initial add eDP support in msm drm driver (v5)

This change adds a new eDP connector in msm drm driver. With this
change, eDP panel can work with msm platform under drm framework.

v1: Initial change

v2: Address Rob's comments
    Use generated header file for register definitions
    Change to devm_* APIs

v3: Address Thierry's comments and rebase on top of atomic changes
    Remove edp_bridge_mode_fixup
    Remove backlight control code and rely on pwm-backlight
    Remove continuous splash screen support for now
    Change to gpiod_* APIs

v4: Fix kbuild test issue

Signed-off-by: Hai Li <hali@codeaurora.org>
[robclark: v5: rebase on drm_bridge changes in drm-next]
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/edp/edp.c

@@ -0,0 +1,208 @@
+/*
+ * Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/of_irq.h>
+#include "edp.h"
+
+static irqreturn_t edp_irq(int irq, void *dev_id)
+{
+	struct msm_edp *edp = dev_id;
+
+	/* Process eDP irq */
+	return msm_edp_ctrl_irq(edp->ctrl);
+}
+
+static void edp_destroy(struct platform_device *pdev)
+{
+	struct msm_edp *edp = platform_get_drvdata(pdev);
+
+	if (!edp)
+		return;
+
+	if (edp->ctrl) {
+		msm_edp_ctrl_destroy(edp->ctrl);
+		edp->ctrl = NULL;
+	}
+
+	platform_set_drvdata(pdev, NULL);
+}
+
+/* construct eDP at bind/probe time, grab all the resources. */
+static struct msm_edp *edp_init(struct platform_device *pdev)
+{
+	struct msm_edp *edp = NULL;
+	int ret;
+
+	if (!pdev) {
+		pr_err("no eDP device\n");
+		ret = -ENXIO;
+		goto fail;
+	}
+
+	edp = devm_kzalloc(&pdev->dev, sizeof(*edp), GFP_KERNEL);
+	if (!edp) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+	DBG("eDP probed=%p", edp);
+
+	edp->pdev = pdev;
+	platform_set_drvdata(pdev, edp);
+
+	ret = msm_edp_ctrl_init(edp);
+	if (ret)
+		goto fail;
+
+	return edp;
+
+fail:
+	if (edp)
+		edp_destroy(pdev);
+
+	return ERR_PTR(ret);
+}
+
+static int edp_bind(struct device *dev, struct device *master, void *data)
+{
+	struct drm_device *drm = dev_get_drvdata(master);
+	struct msm_drm_private *priv = drm->dev_private;
+	struct msm_edp *edp;
+
+	DBG("");
+	edp = edp_init(to_platform_device(dev));
+	if (IS_ERR(edp))
+		return PTR_ERR(edp);
+	priv->edp = edp;
+
+	return 0;
+}
+
+static void edp_unbind(struct device *dev, struct device *master, void *data)
+{
+	struct drm_device *drm = dev_get_drvdata(master);
+	struct msm_drm_private *priv = drm->dev_private;
+
+	DBG("");
+	if (priv->edp) {
+		edp_destroy(to_platform_device(dev));
+		priv->edp = NULL;
+	}
+}
+
+static const struct component_ops edp_ops = {
+		.bind   = edp_bind,
+		.unbind = edp_unbind,
+};
+
+static int edp_dev_probe(struct platform_device *pdev)
+{
+	DBG("");
+	return component_add(&pdev->dev, &edp_ops);
+}
+
+static int edp_dev_remove(struct platform_device *pdev)
+{
+	DBG("");
+	component_del(&pdev->dev, &edp_ops);
+	return 0;
+}
+
+static const struct of_device_id dt_match[] = {
+	{ .compatible = "qcom,mdss-edp" },
+	{}
+};
+
+static struct platform_driver edp_driver = {
+	.probe = edp_dev_probe,
+	.remove = edp_dev_remove,
+	.driver = {
+		.name = "msm_edp",
+		.of_match_table = dt_match,
+	},
+};
+
+void __init msm_edp_register(void)
+{
+	DBG("");
+	platform_driver_register(&edp_driver);
+}
+
+void __exit msm_edp_unregister(void)
+{
+	DBG("");
+	platform_driver_unregister(&edp_driver);
+}
+
+/* Second part of initialization, the drm/kms level modeset_init */
+int msm_edp_modeset_init(struct msm_edp *edp, struct drm_device *dev,
+				struct drm_encoder *encoder)
+{
+	struct platform_device *pdev = edp->pdev;
+	struct msm_drm_private *priv = dev->dev_private;
+	int ret;
+
+	edp->encoder = encoder;
+	edp->dev = dev;
+
+	edp->bridge = msm_edp_bridge_init(edp);
+	if (IS_ERR(edp->bridge)) {
+		ret = PTR_ERR(edp->bridge);
+		dev_err(dev->dev, "failed to create eDP bridge: %d\n", ret);
+		edp->bridge = NULL;
+		goto fail;
+	}
+
+	edp->connector = msm_edp_connector_init(edp);
+	if (IS_ERR(edp->connector)) {
+		ret = PTR_ERR(edp->connector);
+		dev_err(dev->dev, "failed to create eDP connector: %d\n", ret);
+		edp->connector = NULL;
+		goto fail;
+	}
+
+	edp->irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
+	if (edp->irq < 0) {
+		ret = edp->irq;
+		dev_err(dev->dev, "failed to get IRQ: %d\n", ret);
+		goto fail;
+	}
+
+	ret = devm_request_irq(&pdev->dev, edp->irq,
+			edp_irq, IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+			"edp_isr", edp);
+	if (ret < 0) {
+		dev_err(dev->dev, "failed to request IRQ%u: %d\n",
+				edp->irq, ret);
+		goto fail;
+	}
+
+	encoder->bridge = edp->bridge;
+
+	priv->bridges[priv->num_bridges++]       = edp->bridge;
+	priv->connectors[priv->num_connectors++] = edp->connector;
+
+	return 0;
+
+fail:
+	/* bridge/connector are normally destroyed by drm */
+	if (edp->bridge) {
+		edp_bridge_destroy(edp->bridge);
+		edp->bridge = NULL;
+	}
+	if (edp->connector) {
+		edp->connector->funcs->destroy(edp->connector);
+		edp->connector = NULL;
+	}
+
+	return ret;
+}