dt-bindings: mtd: ingenic: Use standard ecc-engine property
[linux/fpc-iii.git] / drivers / gpu / drm / drm_client.c
blob9b2bd28dde0a61b3202adfa726c800231f022cd9
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright 2018 Noralf Trønnes
4 */
6 #include <linux/list.h>
7 #include <linux/module.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_gem.h>
19 #include <drm/drm_mode.h>
20 #include <drm/drm_print.h>
21 #include <drm/drmP.h>
23 #include "drm_crtc_internal.h"
24 #include "drm_internal.h"
26 /**
27 * DOC: overview
29 * This library provides support for clients running in the kernel like fbdev and bootsplash.
30 * Currently it's only partially implemented, just enough to support fbdev.
32 * GEM drivers which provide a GEM based dumb buffer with a virtual address are supported.
35 static int drm_client_open(struct drm_client_dev *client)
37 struct drm_device *dev = client->dev;
38 struct drm_file *file;
40 file = drm_file_alloc(dev->primary);
41 if (IS_ERR(file))
42 return PTR_ERR(file);
44 mutex_lock(&dev->filelist_mutex);
45 list_add(&file->lhead, &dev->filelist_internal);
46 mutex_unlock(&dev->filelist_mutex);
48 client->file = file;
50 return 0;
53 static void drm_client_close(struct drm_client_dev *client)
55 struct drm_device *dev = client->dev;
57 mutex_lock(&dev->filelist_mutex);
58 list_del(&client->file->lhead);
59 mutex_unlock(&dev->filelist_mutex);
61 drm_file_free(client->file);
63 EXPORT_SYMBOL(drm_client_close);
65 /**
66 * drm_client_init - Initialise a DRM client
67 * @dev: DRM device
68 * @client: DRM client
69 * @name: Client name
70 * @funcs: DRM client functions (optional)
72 * This initialises the client and opens a &drm_file. Use drm_client_add() to complete the process.
73 * The caller needs to hold a reference on @dev before calling this function.
74 * The client is freed when the &drm_device is unregistered. See drm_client_release().
76 * Returns:
77 * Zero on success or negative error code on failure.
79 int drm_client_init(struct drm_device *dev, struct drm_client_dev *client,
80 const char *name, const struct drm_client_funcs *funcs)
82 int ret;
84 if (!drm_core_check_feature(dev, DRIVER_MODESET) || !dev->driver->dumb_create)
85 return -EOPNOTSUPP;
87 if (funcs && !try_module_get(funcs->owner))
88 return -ENODEV;
90 client->dev = dev;
91 client->name = name;
92 client->funcs = funcs;
94 ret = drm_client_open(client);
95 if (ret)
96 goto err_put_module;
98 drm_dev_get(dev);
100 return 0;
102 err_put_module:
103 if (funcs)
104 module_put(funcs->owner);
106 return ret;
108 EXPORT_SYMBOL(drm_client_init);
111 * drm_client_add - Add client to the device list
112 * @client: DRM client
114 * Add the client to the &drm_device client list to activate its callbacks.
115 * @client must be initialized by a call to drm_client_init(). After
116 * drm_client_add() it is no longer permissible to call drm_client_release()
117 * directly (outside the unregister callback), instead cleanup will happen
118 * automatically on driver unload.
120 void drm_client_add(struct drm_client_dev *client)
122 struct drm_device *dev = client->dev;
124 mutex_lock(&dev->clientlist_mutex);
125 list_add(&client->list, &dev->clientlist);
126 mutex_unlock(&dev->clientlist_mutex);
128 EXPORT_SYMBOL(drm_client_add);
131 * drm_client_release - Release DRM client resources
132 * @client: DRM client
134 * Releases resources by closing the &drm_file that was opened by drm_client_init().
135 * It is called automatically if the &drm_client_funcs.unregister callback is _not_ set.
137 * This function should only be called from the unregister callback. An exception
138 * is fbdev which cannot free the buffer if userspace has open file descriptors.
140 * Note:
141 * Clients cannot initiate a release by themselves. This is done to keep the code simple.
142 * The driver has to be unloaded before the client can be unloaded.
144 void drm_client_release(struct drm_client_dev *client)
146 struct drm_device *dev = client->dev;
148 DRM_DEV_DEBUG_KMS(dev->dev, "%s\n", client->name);
150 drm_client_close(client);
151 drm_dev_put(dev);
152 if (client->funcs)
153 module_put(client->funcs->owner);
155 EXPORT_SYMBOL(drm_client_release);
157 void drm_client_dev_unregister(struct drm_device *dev)
159 struct drm_client_dev *client, *tmp;
161 if (!drm_core_check_feature(dev, DRIVER_MODESET))
162 return;
164 mutex_lock(&dev->clientlist_mutex);
165 list_for_each_entry_safe(client, tmp, &dev->clientlist, list) {
166 list_del(&client->list);
167 if (client->funcs && client->funcs->unregister) {
168 client->funcs->unregister(client);
169 } else {
170 drm_client_release(client);
171 kfree(client);
174 mutex_unlock(&dev->clientlist_mutex);
178 * drm_client_dev_hotplug - Send hotplug event to clients
179 * @dev: DRM device
181 * This function calls the &drm_client_funcs.hotplug callback on the attached clients.
183 * drm_kms_helper_hotplug_event() calls this function, so drivers that use it
184 * don't need to call this function themselves.
186 void drm_client_dev_hotplug(struct drm_device *dev)
188 struct drm_client_dev *client;
189 int ret;
191 if (!drm_core_check_feature(dev, DRIVER_MODESET))
192 return;
194 mutex_lock(&dev->clientlist_mutex);
195 list_for_each_entry(client, &dev->clientlist, list) {
196 if (!client->funcs || !client->funcs->hotplug)
197 continue;
199 ret = client->funcs->hotplug(client);
200 DRM_DEV_DEBUG_KMS(dev->dev, "%s: ret=%d\n", client->name, ret);
202 mutex_unlock(&dev->clientlist_mutex);
204 EXPORT_SYMBOL(drm_client_dev_hotplug);
206 void drm_client_dev_restore(struct drm_device *dev)
208 struct drm_client_dev *client;
209 int ret;
211 if (!drm_core_check_feature(dev, DRIVER_MODESET))
212 return;
214 mutex_lock(&dev->clientlist_mutex);
215 list_for_each_entry(client, &dev->clientlist, list) {
216 if (!client->funcs || !client->funcs->restore)
217 continue;
219 ret = client->funcs->restore(client);
220 DRM_DEV_DEBUG_KMS(dev->dev, "%s: ret=%d\n", client->name, ret);
221 if (!ret) /* The first one to return zero gets the privilege to restore */
222 break;
224 mutex_unlock(&dev->clientlist_mutex);
227 static void drm_client_buffer_delete(struct drm_client_buffer *buffer)
229 struct drm_device *dev = buffer->client->dev;
231 drm_gem_vunmap(buffer->gem, buffer->vaddr);
233 if (buffer->gem)
234 drm_gem_object_put_unlocked(buffer->gem);
236 if (buffer->handle)
237 drm_mode_destroy_dumb(dev, buffer->handle, buffer->client->file);
239 kfree(buffer);
242 static struct drm_client_buffer *
243 drm_client_buffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format)
245 struct drm_mode_create_dumb dumb_args = { };
246 struct drm_device *dev = client->dev;
247 struct drm_client_buffer *buffer;
248 struct drm_gem_object *obj;
249 void *vaddr;
250 int ret;
252 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
253 if (!buffer)
254 return ERR_PTR(-ENOMEM);
256 buffer->client = client;
258 dumb_args.width = width;
259 dumb_args.height = height;
260 dumb_args.bpp = drm_format_plane_cpp(format, 0) * 8;
261 ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
262 if (ret)
263 goto err_delete;
265 buffer->handle = dumb_args.handle;
266 buffer->pitch = dumb_args.pitch;
268 obj = drm_gem_object_lookup(client->file, dumb_args.handle);
269 if (!obj) {
270 ret = -ENOENT;
271 goto err_delete;
274 buffer->gem = obj;
277 * FIXME: The dependency on GEM here isn't required, we could
278 * convert the driver handle to a dma-buf instead and use the
279 * backend-agnostic dma-buf vmap support instead. This would
280 * require that the handle2fd prime ioctl is reworked to pull the
281 * fd_install step out of the driver backend hooks, to make that
282 * final step optional for internal users.
284 vaddr = drm_gem_vmap(obj);
285 if (IS_ERR(vaddr)) {
286 ret = PTR_ERR(vaddr);
287 goto err_delete;
290 buffer->vaddr = vaddr;
292 return buffer;
294 err_delete:
295 drm_client_buffer_delete(buffer);
297 return ERR_PTR(ret);
300 static void drm_client_buffer_rmfb(struct drm_client_buffer *buffer)
302 int ret;
304 if (!buffer->fb)
305 return;
307 ret = drm_mode_rmfb(buffer->client->dev, buffer->fb->base.id, buffer->client->file);
308 if (ret)
309 DRM_DEV_ERROR(buffer->client->dev->dev,
310 "Error removing FB:%u (%d)\n", buffer->fb->base.id, ret);
312 buffer->fb = NULL;
315 static int drm_client_buffer_addfb(struct drm_client_buffer *buffer,
316 u32 width, u32 height, u32 format)
318 struct drm_client_dev *client = buffer->client;
319 struct drm_mode_fb_cmd fb_req = { };
320 const struct drm_format_info *info;
321 int ret;
323 info = drm_format_info(format);
324 fb_req.bpp = info->cpp[0] * 8;
325 fb_req.depth = info->depth;
326 fb_req.width = width;
327 fb_req.height = height;
328 fb_req.handle = buffer->handle;
329 fb_req.pitch = buffer->pitch;
331 ret = drm_mode_addfb(client->dev, &fb_req, client->file);
332 if (ret)
333 return ret;
335 buffer->fb = drm_framebuffer_lookup(client->dev, buffer->client->file, fb_req.fb_id);
336 if (WARN_ON(!buffer->fb))
337 return -ENOENT;
339 /* drop the reference we picked up in framebuffer lookup */
340 drm_framebuffer_put(buffer->fb);
342 strscpy(buffer->fb->comm, client->name, TASK_COMM_LEN);
344 return 0;
348 * drm_client_framebuffer_create - Create a client framebuffer
349 * @client: DRM client
350 * @width: Framebuffer width
351 * @height: Framebuffer height
352 * @format: Buffer format
354 * This function creates a &drm_client_buffer which consists of a
355 * &drm_framebuffer backed by a dumb buffer.
356 * Call drm_client_framebuffer_delete() to free the buffer.
358 * Returns:
359 * Pointer to a client buffer or an error pointer on failure.
361 struct drm_client_buffer *
362 drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format)
364 struct drm_client_buffer *buffer;
365 int ret;
367 buffer = drm_client_buffer_create(client, width, height, format);
368 if (IS_ERR(buffer))
369 return buffer;
371 ret = drm_client_buffer_addfb(buffer, width, height, format);
372 if (ret) {
373 drm_client_buffer_delete(buffer);
374 return ERR_PTR(ret);
377 return buffer;
379 EXPORT_SYMBOL(drm_client_framebuffer_create);
382 * drm_client_framebuffer_delete - Delete a client framebuffer
383 * @buffer: DRM client buffer (can be NULL)
385 void drm_client_framebuffer_delete(struct drm_client_buffer *buffer)
387 if (!buffer)
388 return;
390 drm_client_buffer_rmfb(buffer);
391 drm_client_buffer_delete(buffer);
393 EXPORT_SYMBOL(drm_client_framebuffer_delete);
395 #ifdef CONFIG_DEBUG_FS
396 static int drm_client_debugfs_internal_clients(struct seq_file *m, void *data)
398 struct drm_info_node *node = m->private;
399 struct drm_device *dev = node->minor->dev;
400 struct drm_printer p = drm_seq_file_printer(m);
401 struct drm_client_dev *client;
403 mutex_lock(&dev->clientlist_mutex);
404 list_for_each_entry(client, &dev->clientlist, list)
405 drm_printf(&p, "%s\n", client->name);
406 mutex_unlock(&dev->clientlist_mutex);
408 return 0;
411 static const struct drm_info_list drm_client_debugfs_list[] = {
412 { "internal_clients", drm_client_debugfs_internal_clients, 0 },
415 int drm_client_debugfs_init(struct drm_minor *minor)
417 return drm_debugfs_create_files(drm_client_debugfs_list,
418 ARRAY_SIZE(drm_client_debugfs_list),
419 minor->debugfs_root, minor);
421 #endif