/* * Copyright (C) 2016 Noralf Trønnes * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include #include #include #include #include #include #include #include /** * DOC: overview * * This library provides driver helpers for very simple display hardware. * * It is based on &drm_simple_display_pipe coupled with a &drm_connector which * has only one fixed &drm_display_mode. The framebuffers are backed by the * cma helper and have support for framebuffer flushing (dirty). * fbdev support is also included. * */ /** * DOC: core * * The driver allocates &tinydrm_device, initializes it using * devm_tinydrm_init(), sets up the pipeline using tinydrm_display_pipe_init() * and registers the DRM device using devm_tinydrm_register(). */ /** * tinydrm_gem_cma_prime_import_sg_table - Produce a CMA GEM object from * another driver's scatter/gather table of pinned pages * @drm: DRM device to import into * @attach: DMA-BUF attachment * @sgt: Scatter/gather table of pinned pages * * This function imports a scatter/gather table exported via DMA-BUF by * another driver using drm_gem_cma_prime_import_sg_table(). It sets the * kernel virtual address on the CMA object. Drivers should use this as their * &drm_driver->gem_prime_import_sg_table callback if they need the virtual * address. tinydrm_gem_cma_free_object() should be used in combination with * this function. * * Returns: * A pointer to a newly created GEM object or an ERR_PTR-encoded negative * error code on failure. */ struct drm_gem_object * tinydrm_gem_cma_prime_import_sg_table(struct drm_device *drm, struct dma_buf_attachment *attach, struct sg_table *sgt) { struct drm_gem_cma_object *cma_obj; struct drm_gem_object *obj; void *vaddr; vaddr = dma_buf_vmap(attach->dmabuf); if (!vaddr) { DRM_ERROR("Failed to vmap PRIME buffer\n"); return ERR_PTR(-ENOMEM); } obj = drm_gem_cma_prime_import_sg_table(drm, attach, sgt); if (IS_ERR(obj)) { dma_buf_vunmap(attach->dmabuf, vaddr); return obj; } cma_obj = to_drm_gem_cma_obj(obj); cma_obj->vaddr = vaddr; return obj; } EXPORT_SYMBOL(tinydrm_gem_cma_prime_import_sg_table); /** * tinydrm_gem_cma_free_object - Free resources associated with a CMA GEM * object * @gem_obj: GEM object to free * * This function frees the backing memory of the CMA GEM object, cleans up the * GEM object state and frees the memory used to store the object itself using * drm_gem_cma_free_object(). It also handles PRIME buffers which has the kernel * virtual address set by tinydrm_gem_cma_prime_import_sg_table(). Drivers * can use this as their &drm_driver->gem_free_object_unlocked callback. */ void tinydrm_gem_cma_free_object(struct drm_gem_object *gem_obj) { if (gem_obj->import_attach) { struct drm_gem_cma_object *cma_obj; cma_obj = to_drm_gem_cma_obj(gem_obj); dma_buf_vunmap(gem_obj->import_attach->dmabuf, cma_obj->vaddr); cma_obj->vaddr = NULL; } drm_gem_cma_free_object(gem_obj); } EXPORT_SYMBOL_GPL(tinydrm_gem_cma_free_object); static struct drm_framebuffer * tinydrm_fb_create(struct drm_device *drm, struct drm_file *file_priv, const struct drm_mode_fb_cmd2 *mode_cmd) { struct tinydrm_device *tdev = drm->dev_private; return drm_gem_fb_create_with_funcs(drm, file_priv, mode_cmd, tdev->fb_funcs); } static const struct drm_mode_config_funcs tinydrm_mode_config_funcs = { .fb_create = tinydrm_fb_create, .atomic_check = drm_atomic_helper_check, .atomic_commit = drm_atomic_helper_commit, }; static int tinydrm_init(struct device *parent, struct tinydrm_device *tdev, const struct drm_framebuffer_funcs *fb_funcs, struct drm_driver *driver) { struct drm_device *drm; mutex_init(&tdev->dirty_lock); tdev->fb_funcs = fb_funcs; /* * We don't embed drm_device, because that prevent us from using * devm_kzalloc() to allocate tinydrm_device in the driver since * drm_dev_unref() frees the structure. The devm_ functions provide * for easy error handling. */ drm = drm_dev_alloc(driver, parent); if (IS_ERR(drm)) return PTR_ERR(drm); tdev->drm = drm; drm->dev_private = tdev; drm_mode_config_init(drm); drm->mode_config.funcs = &tinydrm_mode_config_funcs; return 0; } static void tinydrm_fini(struct tinydrm_device *tdev) { drm_mode_config_cleanup(tdev->drm); mutex_destroy(&tdev->dirty_lock); tdev->drm->dev_private = NULL; drm_dev_unref(tdev->drm); } static void devm_tinydrm_release(void *data) { tinydrm_fini(data); } /** * devm_tinydrm_init - Initialize tinydrm device * @parent: Parent device object * @tdev: tinydrm device * @fb_funcs: Framebuffer functions * @driver: DRM driver * * This function initializes @tdev, the underlying DRM device and it's * mode_config. Resources will be automatically freed on driver detach (devres) * using drm_mode_config_cleanup() and drm_dev_unref(). * * Returns: * Zero on success, negative error code on failure. */ int devm_tinydrm_init(struct device *parent, struct tinydrm_device *tdev, const struct drm_framebuffer_funcs *fb_funcs, struct drm_driver *driver) { int ret; ret = tinydrm_init(parent, tdev, fb_funcs, driver); if (ret) return ret; ret = devm_add_action(parent, devm_tinydrm_release, tdev); if (ret) tinydrm_fini(tdev); return ret; } EXPORT_SYMBOL(devm_tinydrm_init); static int tinydrm_register(struct tinydrm_device *tdev) { struct drm_device *drm = tdev->drm; int ret; ret = drm_dev_register(tdev->drm, 0); if (ret) return ret; ret = drm_fb_cma_fbdev_init_with_funcs(drm, 0, 0, tdev->fb_funcs); if (ret) DRM_ERROR("Failed to initialize fbdev: %d\n", ret); return 0; } static void tinydrm_unregister(struct tinydrm_device *tdev) { drm_atomic_helper_shutdown(tdev->drm); drm_fb_cma_fbdev_fini(tdev->drm); drm_dev_unregister(tdev->drm); } static void devm_tinydrm_register_release(void *data) { tinydrm_unregister(data); } /** * devm_tinydrm_register - Register tinydrm device * @tdev: tinydrm device * * This function registers the underlying DRM device and fbdev. * These resources will be automatically unregistered on driver detach (devres) * and the display pipeline will be disabled. * * Returns: * Zero on success, negative error code on failure. */ int devm_tinydrm_register(struct tinydrm_device *tdev) { struct device *dev = tdev->drm->dev; int ret; ret = tinydrm_register(tdev); if (ret) return ret; ret = devm_add_action(dev, devm_tinydrm_register_release, tdev); if (ret) tinydrm_unregister(tdev); return ret; } EXPORT_SYMBOL(devm_tinydrm_register); /** * tinydrm_shutdown - Shutdown tinydrm * @tdev: tinydrm device * * This function makes sure that the display pipeline is disabled. * Used by drivers in their shutdown callback to turn off the display * on machine shutdown and reboot. */ void tinydrm_shutdown(struct tinydrm_device *tdev) { drm_atomic_helper_shutdown(tdev->drm); } EXPORT_SYMBOL(tinydrm_shutdown); MODULE_LICENSE("GPL");