1 // SPDX-License-Identifier: GPL-2.0 or MIT
3 * Copyright 2018 Noralf Trønnes
6 #include <linux/iosys-map.h>
7 #include <linux/list.h>
8 #include <linux/mutex.h>
9 #include <linux/seq_file.h>
10 #include <linux/slab.h>
12 #include <drm/drm_client.h>
13 #include <drm/drm_debugfs.h>
14 #include <drm/drm_device.h>
15 #include <drm/drm_drv.h>
16 #include <drm/drm_file.h>
17 #include <drm/drm_fourcc.h>
18 #include <drm/drm_framebuffer.h>
19 #include <drm/drm_gem.h>
20 #include <drm/drm_mode.h>
21 #include <drm/drm_print.h>
23 #include "drm_crtc_internal.h"
24 #include "drm_internal.h"
29 * This library provides support for clients running in the kernel like fbdev and bootsplash.
31 * GEM drivers which provide a GEM based dumb buffer with a virtual address are supported.
34 static int drm_client_open(struct drm_client_dev *client)
36 struct drm_device *dev = client->dev;
37 struct drm_file *file;
39 file = drm_file_alloc(dev->primary);
43 mutex_lock(&dev->filelist_mutex);
44 list_add(&file->lhead, &dev->filelist_internal);
45 mutex_unlock(&dev->filelist_mutex);
52 static void drm_client_close(struct drm_client_dev *client)
54 struct drm_device *dev = client->dev;
56 mutex_lock(&dev->filelist_mutex);
57 list_del(&client->file->lhead);
58 mutex_unlock(&dev->filelist_mutex);
60 drm_file_free(client->file);
64 * drm_client_init - Initialise a DRM client
68 * @funcs: DRM client functions (optional)
70 * This initialises the client and opens a &drm_file.
71 * Use drm_client_register() to complete the process.
72 * The caller needs to hold a reference on @dev before calling this function.
73 * The client is freed when the &drm_device is unregistered. See drm_client_release().
76 * Zero on success or negative error code on failure.
78 int drm_client_init(struct drm_device *dev, struct drm_client_dev *client,
79 const char *name, const struct drm_client_funcs *funcs)
83 if (!drm_core_check_feature(dev, DRIVER_MODESET) || !dev->driver->dumb_create)
88 client->funcs = funcs;
90 ret = drm_client_modeset_create(client);
94 ret = drm_client_open(client);
103 drm_client_modeset_free(client);
106 EXPORT_SYMBOL(drm_client_init);
109 * drm_client_register - Register client
110 * @client: DRM client
112 * Add the client to the &drm_device client list to activate its callbacks.
113 * @client must be initialized by a call to drm_client_init(). After
114 * drm_client_register() it is no longer permissible to call drm_client_release()
115 * directly (outside the unregister callback), instead cleanup will happen
116 * automatically on driver unload.
118 * Registering a client generates a hotplug event that allows the client
119 * to set up its display from pre-existing outputs. The client must have
120 * initialized its state to able to handle the hotplug event successfully.
122 void drm_client_register(struct drm_client_dev *client)
124 struct drm_device *dev = client->dev;
127 mutex_lock(&dev->clientlist_mutex);
128 list_add(&client->list, &dev->clientlist);
130 if (client->funcs && client->funcs->hotplug) {
132 * Perform an initial hotplug event to pick up the
133 * display configuration for the client. This step
134 * has to be performed *after* registering the client
135 * in the list of clients, or a concurrent hotplug
136 * event might be lost; leaving the display off.
138 * Hold the clientlist_mutex as for a regular hotplug
141 ret = client->funcs->hotplug(client);
143 drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
145 mutex_unlock(&dev->clientlist_mutex);
147 EXPORT_SYMBOL(drm_client_register);
150 * drm_client_release - Release DRM client resources
151 * @client: DRM client
153 * Releases resources by closing the &drm_file that was opened by drm_client_init().
154 * It is called automatically if the &drm_client_funcs.unregister callback is _not_ set.
156 * This function should only be called from the unregister callback. An exception
157 * is fbdev which cannot free the buffer if userspace has open file descriptors.
160 * Clients cannot initiate a release by themselves. This is done to keep the code simple.
161 * The driver has to be unloaded before the client can be unloaded.
163 void drm_client_release(struct drm_client_dev *client)
165 struct drm_device *dev = client->dev;
167 drm_dbg_kms(dev, "%s\n", client->name);
169 drm_client_modeset_free(client);
170 drm_client_close(client);
173 EXPORT_SYMBOL(drm_client_release);
176 * drm_client_dev_unregister - Unregister clients
179 * This function releases all clients by calling each client's
180 * &drm_client_funcs.unregister callback. The callback function
181 * is responsibe for releaseing all resources including the client
184 * The helper drm_dev_unregister() calls this function. Drivers
185 * that use it don't need to call this function themselves.
187 void drm_client_dev_unregister(struct drm_device *dev)
189 struct drm_client_dev *client, *tmp;
191 if (!drm_core_check_feature(dev, DRIVER_MODESET))
194 mutex_lock(&dev->clientlist_mutex);
195 list_for_each_entry_safe(client, tmp, &dev->clientlist, list) {
196 list_del(&client->list);
197 if (client->funcs && client->funcs->unregister) {
198 client->funcs->unregister(client);
200 drm_client_release(client);
204 mutex_unlock(&dev->clientlist_mutex);
206 EXPORT_SYMBOL(drm_client_dev_unregister);
209 * drm_client_dev_hotplug - Send hotplug event to clients
212 * This function calls the &drm_client_funcs.hotplug callback on the attached clients.
214 * drm_kms_helper_hotplug_event() calls this function, so drivers that use it
215 * don't need to call this function themselves.
217 void drm_client_dev_hotplug(struct drm_device *dev)
219 struct drm_client_dev *client;
222 if (!drm_core_check_feature(dev, DRIVER_MODESET))
225 if (!dev->mode_config.num_connector) {
226 drm_dbg_kms(dev, "No connectors found, will not send hotplug events!\n");
230 mutex_lock(&dev->clientlist_mutex);
231 list_for_each_entry(client, &dev->clientlist, list) {
232 if (!client->funcs || !client->funcs->hotplug)
235 if (client->hotplug_failed)
238 ret = client->funcs->hotplug(client);
239 drm_dbg_kms(dev, "%s: ret=%d\n", client->name, ret);
241 client->hotplug_failed = true;
243 mutex_unlock(&dev->clientlist_mutex);
245 EXPORT_SYMBOL(drm_client_dev_hotplug);
247 void drm_client_dev_restore(struct drm_device *dev)
249 struct drm_client_dev *client;
252 if (!drm_core_check_feature(dev, DRIVER_MODESET))
255 mutex_lock(&dev->clientlist_mutex);
256 list_for_each_entry(client, &dev->clientlist, list) {
257 if (!client->funcs || !client->funcs->restore)
260 ret = client->funcs->restore(client);
261 drm_dbg_kms(dev, "%s: ret=%d\n", client->name, ret);
262 if (!ret) /* The first one to return zero gets the privilege to restore */
265 mutex_unlock(&dev->clientlist_mutex);
268 static void drm_client_buffer_delete(struct drm_client_buffer *buffer)
271 drm_gem_vunmap_unlocked(buffer->gem, &buffer->map);
272 drm_gem_object_put(buffer->gem);
278 static struct drm_client_buffer *
279 drm_client_buffer_create(struct drm_client_dev *client, u32 width, u32 height,
280 u32 format, u32 *handle)
282 const struct drm_format_info *info = drm_format_info(format);
283 struct drm_mode_create_dumb dumb_args = { };
284 struct drm_device *dev = client->dev;
285 struct drm_client_buffer *buffer;
286 struct drm_gem_object *obj;
289 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
291 return ERR_PTR(-ENOMEM);
293 buffer->client = client;
295 dumb_args.width = width;
296 dumb_args.height = height;
297 dumb_args.bpp = drm_format_info_bpp(info, 0);
298 ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
302 obj = drm_gem_object_lookup(client->file, dumb_args.handle);
308 buffer->pitch = dumb_args.pitch;
310 *handle = dumb_args.handle;
315 drm_client_buffer_delete(buffer);
321 * drm_client_buffer_vmap_local - Map DRM client buffer into address space
322 * @buffer: DRM client buffer
323 * @map_copy: Returns the mapped memory's address
325 * This function maps a client buffer into kernel address space. If the
326 * buffer is already mapped, it returns the existing mapping's address.
328 * Client buffer mappings are not ref'counted. Each call to
329 * drm_client_buffer_vmap_local() should be closely followed by a call to
330 * drm_client_buffer_vunmap_local(). See drm_client_buffer_vmap() for
331 * long-term mappings.
333 * The returned address is a copy of the internal value. In contrast to
334 * other vmap interfaces, you don't need it for the client's vunmap
335 * function. So you can modify it at will during blit and draw operations.
338 * 0 on success, or a negative errno code otherwise.
340 int drm_client_buffer_vmap_local(struct drm_client_buffer *buffer,
341 struct iosys_map *map_copy)
343 struct drm_gem_object *gem = buffer->gem;
344 struct iosys_map *map = &buffer->map;
349 ret = drm_gem_vmap(gem, map);
351 goto err_drm_gem_vmap_unlocked;
356 err_drm_gem_vmap_unlocked:
360 EXPORT_SYMBOL(drm_client_buffer_vmap_local);
363 * drm_client_buffer_vunmap_local - Unmap DRM client buffer
364 * @buffer: DRM client buffer
366 * This function removes a client buffer's memory mapping established
367 * with drm_client_buffer_vunmap_local(). Calling this function is only
368 * required by clients that manage their buffer mappings by themselves.
370 void drm_client_buffer_vunmap_local(struct drm_client_buffer *buffer)
372 struct drm_gem_object *gem = buffer->gem;
373 struct iosys_map *map = &buffer->map;
375 drm_gem_vunmap(gem, map);
378 EXPORT_SYMBOL(drm_client_buffer_vunmap_local);
381 * drm_client_buffer_vmap - Map DRM client buffer into address space
382 * @buffer: DRM client buffer
383 * @map_copy: Returns the mapped memory's address
385 * This function maps a client buffer into kernel address space. If the
386 * buffer is already mapped, it returns the existing mapping's address.
388 * Client buffer mappings are not ref'counted. Each call to
389 * drm_client_buffer_vmap() should be followed by a call to
390 * drm_client_buffer_vunmap(); or the client buffer should be mapped
391 * throughout its lifetime.
393 * The returned address is a copy of the internal value. In contrast to
394 * other vmap interfaces, you don't need it for the client's vunmap
395 * function. So you can modify it at will during blit and draw operations.
398 * 0 on success, or a negative errno code otherwise.
401 drm_client_buffer_vmap(struct drm_client_buffer *buffer,
402 struct iosys_map *map_copy)
404 struct drm_gem_object *gem = buffer->gem;
405 struct iosys_map *map = &buffer->map;
410 ret = drm_gem_pin_locked(gem);
412 goto err_drm_gem_pin_locked;
413 ret = drm_gem_vmap(gem, map);
415 goto err_drm_gem_vmap;
424 drm_gem_unpin_locked(buffer->gem);
425 err_drm_gem_pin_locked:
429 EXPORT_SYMBOL(drm_client_buffer_vmap);
432 * drm_client_buffer_vunmap - Unmap DRM client buffer
433 * @buffer: DRM client buffer
435 * This function removes a client buffer's memory mapping. Calling this
436 * function is only required by clients that manage their buffer mappings
439 void drm_client_buffer_vunmap(struct drm_client_buffer *buffer)
441 struct drm_gem_object *gem = buffer->gem;
442 struct iosys_map *map = &buffer->map;
445 drm_gem_vunmap(gem, map);
446 drm_gem_unpin_locked(gem);
449 EXPORT_SYMBOL(drm_client_buffer_vunmap);
451 static void drm_client_buffer_rmfb(struct drm_client_buffer *buffer)
458 ret = drm_mode_rmfb(buffer->client->dev, buffer->fb->base.id, buffer->client->file);
460 drm_err(buffer->client->dev,
461 "Error removing FB:%u (%d)\n", buffer->fb->base.id, ret);
466 static int drm_client_buffer_addfb(struct drm_client_buffer *buffer,
467 u32 width, u32 height, u32 format,
470 struct drm_client_dev *client = buffer->client;
471 struct drm_mode_fb_cmd2 fb_req = { };
474 fb_req.width = width;
475 fb_req.height = height;
476 fb_req.pixel_format = format;
477 fb_req.handles[0] = handle;
478 fb_req.pitches[0] = buffer->pitch;
480 ret = drm_mode_addfb2(client->dev, &fb_req, client->file);
484 buffer->fb = drm_framebuffer_lookup(client->dev, buffer->client->file, fb_req.fb_id);
485 if (WARN_ON(!buffer->fb))
488 /* drop the reference we picked up in framebuffer lookup */
489 drm_framebuffer_put(buffer->fb);
491 strscpy(buffer->fb->comm, client->name, TASK_COMM_LEN);
497 * drm_client_framebuffer_create - Create a client framebuffer
498 * @client: DRM client
499 * @width: Framebuffer width
500 * @height: Framebuffer height
501 * @format: Buffer format
503 * This function creates a &drm_client_buffer which consists of a
504 * &drm_framebuffer backed by a dumb buffer.
505 * Call drm_client_framebuffer_delete() to free the buffer.
508 * Pointer to a client buffer or an error pointer on failure.
510 struct drm_client_buffer *
511 drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format)
513 struct drm_client_buffer *buffer;
517 buffer = drm_client_buffer_create(client, width, height, format,
522 ret = drm_client_buffer_addfb(buffer, width, height, format, handle);
525 * The handle is only needed for creating the framebuffer, destroy it
526 * again to solve a circular dependency should anybody export the GEM
527 * object as DMA-buf. The framebuffer and our buffer structure are still
528 * holding references to the GEM object to prevent its destruction.
530 drm_mode_destroy_dumb(client->dev, handle, client->file);
533 drm_client_buffer_delete(buffer);
539 EXPORT_SYMBOL(drm_client_framebuffer_create);
542 * drm_client_framebuffer_delete - Delete a client framebuffer
543 * @buffer: DRM client buffer (can be NULL)
545 void drm_client_framebuffer_delete(struct drm_client_buffer *buffer)
550 drm_client_buffer_rmfb(buffer);
551 drm_client_buffer_delete(buffer);
553 EXPORT_SYMBOL(drm_client_framebuffer_delete);
556 * drm_client_framebuffer_flush - Manually flush client framebuffer
557 * @buffer: DRM client buffer (can be NULL)
558 * @rect: Damage rectangle (if NULL flushes all)
560 * This calls &drm_framebuffer_funcs->dirty (if present) to flush buffer changes
561 * for drivers that need it.
564 * Zero on success or negative error code on failure.
566 int drm_client_framebuffer_flush(struct drm_client_buffer *buffer, struct drm_rect *rect)
568 if (!buffer || !buffer->fb || !buffer->fb->funcs->dirty)
572 struct drm_clip_rect clip = {
579 return buffer->fb->funcs->dirty(buffer->fb, buffer->client->file,
583 return buffer->fb->funcs->dirty(buffer->fb, buffer->client->file,
586 EXPORT_SYMBOL(drm_client_framebuffer_flush);
588 #ifdef CONFIG_DEBUG_FS
589 static int drm_client_debugfs_internal_clients(struct seq_file *m, void *data)
591 struct drm_debugfs_entry *entry = m->private;
592 struct drm_device *dev = entry->dev;
593 struct drm_printer p = drm_seq_file_printer(m);
594 struct drm_client_dev *client;
596 mutex_lock(&dev->clientlist_mutex);
597 list_for_each_entry(client, &dev->clientlist, list)
598 drm_printf(&p, "%s\n", client->name);
599 mutex_unlock(&dev->clientlist_mutex);
604 static const struct drm_debugfs_info drm_client_debugfs_list[] = {
605 { "internal_clients", drm_client_debugfs_internal_clients, 0 },
608 void drm_client_debugfs_init(struct drm_device *dev)
610 drm_debugfs_add_files(dev, drm_client_debugfs_list,
611 ARRAY_SIZE(drm_client_debugfs_list));