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Diffstat (limited to 'drivers/gpu/drm/drm_panel.c')
-rw-r--r--drivers/gpu/drm/drm_panel.c349
1 files changed, 349 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
new file mode 100644
index 000000000..f634371c7
--- /dev/null
+++ b/drivers/gpu/drm/drm_panel.c
@@ -0,0 +1,349 @@
+/*
+ * Copyright (C) 2013, NVIDIA Corporation. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sub license,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/module.h>
+
+#include <drm/drm_crtc.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+
+static DEFINE_MUTEX(panel_lock);
+static LIST_HEAD(panel_list);
+
+/**
+ * DOC: drm panel
+ *
+ * The DRM panel helpers allow drivers to register panel objects with a
+ * central registry and provide functions to retrieve those panels in display
+ * drivers.
+ *
+ * For easy integration into drivers using the &drm_bridge infrastructure please
+ * take look at drm_panel_bridge_add() and devm_drm_panel_bridge_add().
+ */
+
+/**
+ * drm_panel_init - initialize a panel
+ * @panel: DRM panel
+ * @dev: parent device of the panel
+ * @funcs: panel operations
+ * @connector_type: the connector type (DRM_MODE_CONNECTOR_*) corresponding to
+ * the panel interface
+ *
+ * Initialize the panel structure for subsequent registration with
+ * drm_panel_add().
+ */
+void drm_panel_init(struct drm_panel *panel, struct device *dev,
+ const struct drm_panel_funcs *funcs, int connector_type)
+{
+ INIT_LIST_HEAD(&panel->list);
+ panel->dev = dev;
+ panel->funcs = funcs;
+ panel->connector_type = connector_type;
+}
+EXPORT_SYMBOL(drm_panel_init);
+
+/**
+ * drm_panel_add - add a panel to the global registry
+ * @panel: panel to add
+ *
+ * Add a panel to the global registry so that it can be looked up by display
+ * drivers.
+ */
+void drm_panel_add(struct drm_panel *panel)
+{
+ mutex_lock(&panel_lock);
+ list_add_tail(&panel->list, &panel_list);
+ mutex_unlock(&panel_lock);
+}
+EXPORT_SYMBOL(drm_panel_add);
+
+/**
+ * drm_panel_remove - remove a panel from the global registry
+ * @panel: DRM panel
+ *
+ * Removes a panel from the global registry.
+ */
+void drm_panel_remove(struct drm_panel *panel)
+{
+ mutex_lock(&panel_lock);
+ list_del_init(&panel->list);
+ mutex_unlock(&panel_lock);
+}
+EXPORT_SYMBOL(drm_panel_remove);
+
+/**
+ * drm_panel_prepare - power on a panel
+ * @panel: DRM panel
+ *
+ * Calling this function will enable power and deassert any reset signals to
+ * the panel. After this has completed it is possible to communicate with any
+ * integrated circuitry via a command bus.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_prepare(struct drm_panel *panel)
+{
+ if (!panel)
+ return -EINVAL;
+
+ if (panel->funcs && panel->funcs->prepare)
+ return panel->funcs->prepare(panel);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_panel_prepare);
+
+/**
+ * drm_panel_unprepare - power off a panel
+ * @panel: DRM panel
+ *
+ * Calling this function will completely power off a panel (assert the panel's
+ * reset, turn off power supplies, ...). After this function has completed, it
+ * is usually no longer possible to communicate with the panel until another
+ * call to drm_panel_prepare().
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_unprepare(struct drm_panel *panel)
+{
+ if (!panel)
+ return -EINVAL;
+
+ if (panel->funcs && panel->funcs->unprepare)
+ return panel->funcs->unprepare(panel);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_panel_unprepare);
+
+/**
+ * drm_panel_enable - enable a panel
+ * @panel: DRM panel
+ *
+ * Calling this function will cause the panel display drivers to be turned on
+ * and the backlight to be enabled. Content will be visible on screen after
+ * this call completes.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_enable(struct drm_panel *panel)
+{
+ int ret;
+
+ if (!panel)
+ return -EINVAL;
+
+ if (panel->funcs && panel->funcs->enable) {
+ ret = panel->funcs->enable(panel);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = backlight_enable(panel->backlight);
+ if (ret < 0)
+ DRM_DEV_INFO(panel->dev, "failed to enable backlight: %d\n",
+ ret);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_panel_enable);
+
+/**
+ * drm_panel_disable - disable a panel
+ * @panel: DRM panel
+ *
+ * This will typically turn off the panel's backlight or disable the display
+ * drivers. For smart panels it should still be possible to communicate with
+ * the integrated circuitry via any command bus after this call.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_disable(struct drm_panel *panel)
+{
+ int ret;
+
+ if (!panel)
+ return -EINVAL;
+
+ ret = backlight_disable(panel->backlight);
+ if (ret < 0)
+ DRM_DEV_INFO(panel->dev, "failed to disable backlight: %d\n",
+ ret);
+
+ if (panel->funcs && panel->funcs->disable)
+ return panel->funcs->disable(panel);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_panel_disable);
+
+/**
+ * drm_panel_get_modes - probe the available display modes of a panel
+ * @panel: DRM panel
+ * @connector: DRM connector
+ *
+ * The modes probed from the panel are automatically added to the connector
+ * that the panel is attached to.
+ *
+ * Return: The number of modes available from the panel on success or a
+ * negative error code on failure.
+ */
+int drm_panel_get_modes(struct drm_panel *panel,
+ struct drm_connector *connector)
+{
+ if (!panel)
+ return -EINVAL;
+
+ if (panel->funcs && panel->funcs->get_modes)
+ return panel->funcs->get_modes(panel, connector);
+
+ return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(drm_panel_get_modes);
+
+#ifdef CONFIG_OF
+/**
+ * of_drm_find_panel - look up a panel using a device tree node
+ * @np: device tree node of the panel
+ *
+ * Searches the set of registered panels for one that matches the given device
+ * tree node. If a matching panel is found, return a pointer to it.
+ *
+ * Return: A pointer to the panel registered for the specified device tree
+ * node or an ERR_PTR() if no panel matching the device tree node can be found.
+ *
+ * Possible error codes returned by this function:
+ *
+ * - EPROBE_DEFER: the panel device has not been probed yet, and the caller
+ * should retry later
+ * - ENODEV: the device is not available (status != "okay" or "ok")
+ */
+struct drm_panel *of_drm_find_panel(const struct device_node *np)
+{
+ struct drm_panel *panel;
+
+ if (!of_device_is_available(np))
+ return ERR_PTR(-ENODEV);
+
+ mutex_lock(&panel_lock);
+
+ list_for_each_entry(panel, &panel_list, list) {
+ if (panel->dev->of_node == np) {
+ mutex_unlock(&panel_lock);
+ return panel;
+ }
+ }
+
+ mutex_unlock(&panel_lock);
+ return ERR_PTR(-EPROBE_DEFER);
+}
+EXPORT_SYMBOL(of_drm_find_panel);
+
+/**
+ * of_drm_get_panel_orientation - look up the orientation of the panel through
+ * the "rotation" binding from a device tree node
+ * @np: device tree node of the panel
+ * @orientation: orientation enum to be filled in
+ *
+ * Looks up the rotation of a panel in the device tree. The orientation of the
+ * panel is expressed as a property name "rotation" in the device tree. The
+ * rotation in the device tree is counter clockwise.
+ *
+ * Return: 0 when a valid rotation value (0, 90, 180, or 270) is read or the
+ * rotation property doesn't exist. Return a negative error code on failure.
+ */
+int of_drm_get_panel_orientation(const struct device_node *np,
+ enum drm_panel_orientation *orientation)
+{
+ int rotation, ret;
+
+ ret = of_property_read_u32(np, "rotation", &rotation);
+ if (ret == -EINVAL) {
+ /* Don't return an error if there's no rotation property. */
+ *orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;
+ return 0;
+ }
+
+ if (ret < 0)
+ return ret;
+
+ if (rotation == 0)
+ *orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
+ else if (rotation == 90)
+ *orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
+ else if (rotation == 180)
+ *orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
+ else if (rotation == 270)
+ *orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
+ else
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL(of_drm_get_panel_orientation);
+#endif
+
+#if IS_REACHABLE(CONFIG_BACKLIGHT_CLASS_DEVICE)
+/**
+ * drm_panel_of_backlight - use backlight device node for backlight
+ * @panel: DRM panel
+ *
+ * Use this function to enable backlight handling if your panel
+ * uses device tree and has a backlight phandle.
+ *
+ * When the panel is enabled backlight will be enabled after a
+ * successful call to &drm_panel_funcs.enable()
+ *
+ * When the panel is disabled backlight will be disabled before the
+ * call to &drm_panel_funcs.disable().
+ *
+ * A typical implementation for a panel driver supporting device tree
+ * will call this function at probe time. Backlight will then be handled
+ * transparently without requiring any intervention from the driver.
+ * drm_panel_of_backlight() must be called after the call to drm_panel_init().
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_of_backlight(struct drm_panel *panel)
+{
+ struct backlight_device *backlight;
+
+ if (!panel || !panel->dev)
+ return -EINVAL;
+
+ backlight = devm_of_find_backlight(panel->dev);
+
+ if (IS_ERR(backlight))
+ return PTR_ERR(backlight);
+
+ panel->backlight = backlight;
+ return 0;
+}
+EXPORT_SYMBOL(drm_panel_of_backlight);
+#endif
+
+MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
+MODULE_DESCRIPTION("DRM panel infrastructure");
+MODULE_LICENSE("GPL and additional rights");