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path: root/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
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Diffstat (limited to 'drivers/gpu/drm/tinydrm/core/tinydrm-core.c')
-rw-r--r--drivers/gpu/drm/tinydrm/core/tinydrm-core.c376
1 files changed, 376 insertions, 0 deletions
diff --git a/drivers/gpu/drm/tinydrm/core/tinydrm-core.c b/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
new file mode 100644
index 000000000000..6a257dd08ee0
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/core/tinydrm-core.c
@@ -0,0 +1,376 @@
+/*
+ * 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 <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/tinydrm/tinydrm.h>
+#include <linux/device.h>
+#include <linux/dma-buf.h>
+
+/**
+ * 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_lastclose - DRM lastclose helper
+ * @drm: DRM device
+ *
+ * This function ensures that fbdev is restored when drm_lastclose() is called
+ * on the last drm_release(). Drivers can use this as their
+ * &drm_driver->lastclose callback.
+ */
+void tinydrm_lastclose(struct drm_device *drm)
+{
+ struct tinydrm_device *tdev = drm->dev_private;
+
+ DRM_DEBUG_KMS("\n");
+ drm_fbdev_cma_restore_mode(tdev->fbdev_cma);
+}
+EXPORT_SYMBOL(tinydrm_lastclose);
+
+/**
+ * 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 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);
+
+const struct file_operations tinydrm_fops = {
+ .owner = THIS_MODULE,
+ .open = drm_open,
+ .release = drm_release,
+ .unlocked_ioctl = drm_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = drm_compat_ioctl,
+#endif
+ .poll = drm_poll,
+ .read = drm_read,
+ .llseek = no_llseek,
+ .mmap = drm_gem_cma_mmap,
+};
+EXPORT_SYMBOL(tinydrm_fops);
+
+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_fb_cma_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 bpp = drm->mode_config.preferred_depth;
+ struct drm_fbdev_cma *fbdev;
+ int ret;
+
+ ret = drm_dev_register(tdev->drm, 0);
+ if (ret)
+ return ret;
+
+ fbdev = drm_fbdev_cma_init_with_funcs(drm, bpp ? bpp : 32,
+ drm->mode_config.num_connector,
+ tdev->fb_funcs);
+ if (IS_ERR(fbdev))
+ DRM_ERROR("Failed to initialize fbdev: %ld\n", PTR_ERR(fbdev));
+ else
+ tdev->fbdev_cma = fbdev;
+
+ return 0;
+}
+
+static void tinydrm_unregister(struct tinydrm_device *tdev)
+{
+ struct drm_fbdev_cma *fbdev_cma = tdev->fbdev_cma;
+
+ drm_crtc_force_disable_all(tdev->drm);
+ /* don't restore fbdev in lastclose, keep pipeline disabled */
+ tdev->fbdev_cma = NULL;
+ drm_dev_unregister(tdev->drm);
+ if (fbdev_cma)
+ drm_fbdev_cma_fini(fbdev_cma);
+}
+
+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_crtc_force_disable_all(tdev->drm);
+}
+EXPORT_SYMBOL(tinydrm_shutdown);
+
+/**
+ * tinydrm_suspend - Suspend tinydrm
+ * @tdev: tinydrm device
+ *
+ * Used in driver PM operations to suspend tinydrm.
+ * Suspends fbdev and DRM.
+ * Resume with tinydrm_resume().
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_suspend(struct tinydrm_device *tdev)
+{
+ struct drm_atomic_state *state;
+
+ if (tdev->suspend_state) {
+ DRM_ERROR("Failed to suspend: state already set\n");
+ return -EINVAL;
+ }
+
+ drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 1);
+ state = drm_atomic_helper_suspend(tdev->drm);
+ if (IS_ERR(state)) {
+ drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 0);
+ return PTR_ERR(state);
+ }
+
+ tdev->suspend_state = state;
+
+ return 0;
+}
+EXPORT_SYMBOL(tinydrm_suspend);
+
+/**
+ * tinydrm_resume - Resume tinydrm
+ * @tdev: tinydrm device
+ *
+ * Used in driver PM operations to resume tinydrm.
+ * Suspend with tinydrm_suspend().
+ *
+ * Returns:
+ * Zero on success, negative error code on failure.
+ */
+int tinydrm_resume(struct tinydrm_device *tdev)
+{
+ struct drm_atomic_state *state = tdev->suspend_state;
+ int ret;
+
+ if (!state) {
+ DRM_ERROR("Failed to resume: state is not set\n");
+ return -EINVAL;
+ }
+
+ tdev->suspend_state = NULL;
+
+ ret = drm_atomic_helper_resume(tdev->drm, state);
+ if (ret) {
+ DRM_ERROR("Error resuming state: %d\n", ret);
+ return ret;
+ }
+
+ drm_fbdev_cma_set_suspend_unlocked(tdev->fbdev_cma, 0);
+
+ return 0;
+}
+EXPORT_SYMBOL(tinydrm_resume);
+
+MODULE_LICENSE("GPL");