Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Created: Fri Jan 19 10:48:35 2001 by faith@acm.org |
| 3 | * |
| 4 | * Copyright 2001 VA Linux Systems, Inc., Sunnyvale, California. |
| 5 | * All Rights Reserved. |
| 6 | * |
| 7 | * Author Rickard E. (Rik) Faith <faith@valinux.com> |
| 8 | * |
| 9 | * Permission is hereby granted, free of charge, to any person obtaining a |
| 10 | * copy of this software and associated documentation files (the "Software"), |
| 11 | * to deal in the Software without restriction, including without limitation |
| 12 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| 13 | * and/or sell copies of the Software, and to permit persons to whom the |
| 14 | * Software is furnished to do so, subject to the following conditions: |
| 15 | * |
| 16 | * The above copyright notice and this permission notice (including the next |
| 17 | * paragraph) shall be included in all copies or substantial portions of the |
| 18 | * Software. |
| 19 | * |
| 20 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 21 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 22 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 23 | * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR |
| 24 | * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
| 25 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
| 26 | * DEALINGS IN THE SOFTWARE. |
| 27 | */ |
| 28 | |
| 29 | #include <linux/debugfs.h> |
| 30 | #include <linux/fs.h> |
| 31 | #include <linux/module.h> |
| 32 | #include <linux/moduleparam.h> |
| 33 | #include <linux/mount.h> |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 34 | #include <linux/pseudo_fs.h> |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 35 | #include <linux/slab.h> |
| 36 | #include <linux/srcu.h> |
| 37 | |
| 38 | #include <drm/drm_client.h> |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 39 | #include <drm/drm_color_mgmt.h> |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 40 | #include <drm/drm_drv.h> |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 41 | #include <drm/drm_file.h> |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 42 | #include <drm/drm_managed.h> |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 43 | #include <drm/drm_mode_object.h> |
| 44 | #include <drm/drm_print.h> |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 45 | |
| 46 | #include "drm_crtc_internal.h" |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 47 | #include "drm_internal.h" |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 48 | #include "drm_legacy.h" |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 49 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 50 | MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl"); |
| 51 | MODULE_DESCRIPTION("DRM shared core routines"); |
| 52 | MODULE_LICENSE("GPL and additional rights"); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 53 | |
| 54 | static DEFINE_SPINLOCK(drm_minor_lock); |
| 55 | static struct idr drm_minors_idr; |
| 56 | |
| 57 | /* |
| 58 | * If the drm core fails to init for whatever reason, |
| 59 | * we should prevent any drivers from registering with it. |
| 60 | * It's best to check this at drm_dev_init(), as some drivers |
| 61 | * prefer to embed struct drm_device into their own device |
| 62 | * structure and call drm_dev_init() themselves. |
| 63 | */ |
| 64 | static bool drm_core_init_complete = false; |
| 65 | |
| 66 | static struct dentry *drm_debugfs_root; |
| 67 | |
| 68 | DEFINE_STATIC_SRCU(drm_unplug_srcu); |
| 69 | |
| 70 | /* |
| 71 | * DRM Minors |
| 72 | * A DRM device can provide several char-dev interfaces on the DRM-Major. Each |
| 73 | * of them is represented by a drm_minor object. Depending on the capabilities |
| 74 | * of the device-driver, different interfaces are registered. |
| 75 | * |
| 76 | * Minors can be accessed via dev->$minor_name. This pointer is either |
| 77 | * NULL or a valid drm_minor pointer and stays valid as long as the device is |
| 78 | * valid. This means, DRM minors have the same life-time as the underlying |
| 79 | * device. However, this doesn't mean that the minor is active. Minors are |
| 80 | * registered and unregistered dynamically according to device-state. |
| 81 | */ |
| 82 | |
| 83 | static struct drm_minor **drm_minor_get_slot(struct drm_device *dev, |
| 84 | unsigned int type) |
| 85 | { |
| 86 | switch (type) { |
| 87 | case DRM_MINOR_PRIMARY: |
| 88 | return &dev->primary; |
| 89 | case DRM_MINOR_RENDER: |
| 90 | return &dev->render; |
| 91 | default: |
| 92 | BUG(); |
| 93 | } |
| 94 | } |
| 95 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 96 | static void drm_minor_alloc_release(struct drm_device *dev, void *data) |
| 97 | { |
| 98 | struct drm_minor *minor = data; |
| 99 | unsigned long flags; |
| 100 | |
| 101 | WARN_ON(dev != minor->dev); |
| 102 | |
| 103 | put_device(minor->kdev); |
| 104 | |
| 105 | spin_lock_irqsave(&drm_minor_lock, flags); |
| 106 | idr_remove(&drm_minors_idr, minor->index); |
| 107 | spin_unlock_irqrestore(&drm_minor_lock, flags); |
| 108 | } |
| 109 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 110 | static int drm_minor_alloc(struct drm_device *dev, unsigned int type) |
| 111 | { |
| 112 | struct drm_minor *minor; |
| 113 | unsigned long flags; |
| 114 | int r; |
| 115 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 116 | minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 117 | if (!minor) |
| 118 | return -ENOMEM; |
| 119 | |
| 120 | minor->type = type; |
| 121 | minor->dev = dev; |
| 122 | |
| 123 | idr_preload(GFP_KERNEL); |
| 124 | spin_lock_irqsave(&drm_minor_lock, flags); |
| 125 | r = idr_alloc(&drm_minors_idr, |
| 126 | NULL, |
| 127 | 64 * type, |
| 128 | 64 * (type + 1), |
| 129 | GFP_NOWAIT); |
| 130 | spin_unlock_irqrestore(&drm_minor_lock, flags); |
| 131 | idr_preload_end(); |
| 132 | |
| 133 | if (r < 0) |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 134 | return r; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 135 | |
| 136 | minor->index = r; |
| 137 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 138 | r = drmm_add_action_or_reset(dev, drm_minor_alloc_release, minor); |
| 139 | if (r) |
| 140 | return r; |
| 141 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 142 | minor->kdev = drm_sysfs_minor_alloc(minor); |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 143 | if (IS_ERR(minor->kdev)) |
| 144 | return PTR_ERR(minor->kdev); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 145 | |
| 146 | *drm_minor_get_slot(dev, type) = minor; |
| 147 | return 0; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | static int drm_minor_register(struct drm_device *dev, unsigned int type) |
| 151 | { |
| 152 | struct drm_minor *minor; |
| 153 | unsigned long flags; |
| 154 | int ret; |
| 155 | |
| 156 | DRM_DEBUG("\n"); |
| 157 | |
| 158 | minor = *drm_minor_get_slot(dev, type); |
| 159 | if (!minor) |
| 160 | return 0; |
| 161 | |
| 162 | ret = drm_debugfs_init(minor, minor->index, drm_debugfs_root); |
| 163 | if (ret) { |
| 164 | DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n"); |
| 165 | goto err_debugfs; |
| 166 | } |
| 167 | |
| 168 | ret = device_add(minor->kdev); |
| 169 | if (ret) |
| 170 | goto err_debugfs; |
| 171 | |
| 172 | /* replace NULL with @minor so lookups will succeed from now on */ |
| 173 | spin_lock_irqsave(&drm_minor_lock, flags); |
| 174 | idr_replace(&drm_minors_idr, minor, minor->index); |
| 175 | spin_unlock_irqrestore(&drm_minor_lock, flags); |
| 176 | |
| 177 | DRM_DEBUG("new minor registered %d\n", minor->index); |
| 178 | return 0; |
| 179 | |
| 180 | err_debugfs: |
| 181 | drm_debugfs_cleanup(minor); |
| 182 | return ret; |
| 183 | } |
| 184 | |
| 185 | static void drm_minor_unregister(struct drm_device *dev, unsigned int type) |
| 186 | { |
| 187 | struct drm_minor *minor; |
| 188 | unsigned long flags; |
| 189 | |
| 190 | minor = *drm_minor_get_slot(dev, type); |
| 191 | if (!minor || !device_is_registered(minor->kdev)) |
| 192 | return; |
| 193 | |
| 194 | /* replace @minor with NULL so lookups will fail from now on */ |
| 195 | spin_lock_irqsave(&drm_minor_lock, flags); |
| 196 | idr_replace(&drm_minors_idr, NULL, minor->index); |
| 197 | spin_unlock_irqrestore(&drm_minor_lock, flags); |
| 198 | |
| 199 | device_del(minor->kdev); |
| 200 | dev_set_drvdata(minor->kdev, NULL); /* safety belt */ |
| 201 | drm_debugfs_cleanup(minor); |
| 202 | } |
| 203 | |
| 204 | /* |
| 205 | * Looks up the given minor-ID and returns the respective DRM-minor object. The |
| 206 | * refence-count of the underlying device is increased so you must release this |
| 207 | * object with drm_minor_release(). |
| 208 | * |
| 209 | * As long as you hold this minor, it is guaranteed that the object and the |
| 210 | * minor->dev pointer will stay valid! However, the device may get unplugged and |
| 211 | * unregistered while you hold the minor. |
| 212 | */ |
| 213 | struct drm_minor *drm_minor_acquire(unsigned int minor_id) |
| 214 | { |
| 215 | struct drm_minor *minor; |
| 216 | unsigned long flags; |
| 217 | |
| 218 | spin_lock_irqsave(&drm_minor_lock, flags); |
| 219 | minor = idr_find(&drm_minors_idr, minor_id); |
| 220 | if (minor) |
| 221 | drm_dev_get(minor->dev); |
| 222 | spin_unlock_irqrestore(&drm_minor_lock, flags); |
| 223 | |
| 224 | if (!minor) { |
| 225 | return ERR_PTR(-ENODEV); |
| 226 | } else if (drm_dev_is_unplugged(minor->dev)) { |
| 227 | drm_dev_put(minor->dev); |
| 228 | return ERR_PTR(-ENODEV); |
| 229 | } |
| 230 | |
| 231 | return minor; |
| 232 | } |
| 233 | |
| 234 | void drm_minor_release(struct drm_minor *minor) |
| 235 | { |
| 236 | drm_dev_put(minor->dev); |
| 237 | } |
| 238 | |
| 239 | /** |
| 240 | * DOC: driver instance overview |
| 241 | * |
| 242 | * A device instance for a drm driver is represented by &struct drm_device. This |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 243 | * is allocated and initialized with devm_drm_dev_alloc(), usually from |
| 244 | * bus-specific ->probe() callbacks implemented by the driver. The driver then |
| 245 | * needs to initialize all the various subsystems for the drm device like memory |
| 246 | * management, vblank handling, modesetting support and initial output |
| 247 | * configuration plus obviously initialize all the corresponding hardware bits. |
| 248 | * Finally when everything is up and running and ready for userspace the device |
| 249 | * instance can be published using drm_dev_register(). |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 250 | * |
| 251 | * There is also deprecated support for initalizing device instances using |
| 252 | * bus-specific helpers and the &drm_driver.load callback. But due to |
| 253 | * backwards-compatibility needs the device instance have to be published too |
| 254 | * early, which requires unpretty global locking to make safe and is therefore |
| 255 | * only support for existing drivers not yet converted to the new scheme. |
| 256 | * |
| 257 | * When cleaning up a device instance everything needs to be done in reverse: |
| 258 | * First unpublish the device instance with drm_dev_unregister(). Then clean up |
| 259 | * any other resources allocated at device initialization and drop the driver's |
| 260 | * reference to &drm_device using drm_dev_put(). |
| 261 | * |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 262 | * Note that any allocation or resource which is visible to userspace must be |
| 263 | * released only when the final drm_dev_put() is called, and not when the |
| 264 | * driver is unbound from the underlying physical struct &device. Best to use |
| 265 | * &drm_device managed resources with drmm_add_action(), drmm_kmalloc() and |
| 266 | * related functions. |
| 267 | * |
| 268 | * devres managed resources like devm_kmalloc() can only be used for resources |
| 269 | * directly related to the underlying hardware device, and only used in code |
| 270 | * paths fully protected by drm_dev_enter() and drm_dev_exit(). |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 271 | * |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 272 | * Display driver example |
| 273 | * ~~~~~~~~~~~~~~~~~~~~~~ |
| 274 | * |
| 275 | * The following example shows a typical structure of a DRM display driver. |
| 276 | * The example focus on the probe() function and the other functions that is |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 277 | * almost always present and serves as a demonstration of devm_drm_dev_alloc(). |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 278 | * |
| 279 | * .. code-block:: c |
| 280 | * |
| 281 | * struct driver_device { |
| 282 | * struct drm_device drm; |
| 283 | * void *userspace_facing; |
| 284 | * struct clk *pclk; |
| 285 | * }; |
| 286 | * |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 287 | * static struct drm_driver driver_drm_driver = { |
| 288 | * [...] |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 289 | * }; |
| 290 | * |
| 291 | * static int driver_probe(struct platform_device *pdev) |
| 292 | * { |
| 293 | * struct driver_device *priv; |
| 294 | * struct drm_device *drm; |
| 295 | * int ret; |
| 296 | * |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 297 | * priv = devm_drm_dev_alloc(&pdev->dev, &driver_drm_driver, |
| 298 | * struct driver_device, drm); |
| 299 | * if (IS_ERR(priv)) |
| 300 | * return PTR_ERR(priv); |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 301 | * drm = &priv->drm; |
| 302 | * |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 303 | * ret = drmm_mode_config_init(drm); |
| 304 | * if (ret) |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 305 | * return ret; |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 306 | * |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 307 | * priv->userspace_facing = drmm_kzalloc(..., GFP_KERNEL); |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 308 | * if (!priv->userspace_facing) |
| 309 | * return -ENOMEM; |
| 310 | * |
| 311 | * priv->pclk = devm_clk_get(dev, "PCLK"); |
| 312 | * if (IS_ERR(priv->pclk)) |
| 313 | * return PTR_ERR(priv->pclk); |
| 314 | * |
| 315 | * // Further setup, display pipeline etc |
| 316 | * |
| 317 | * platform_set_drvdata(pdev, drm); |
| 318 | * |
| 319 | * drm_mode_config_reset(drm); |
| 320 | * |
| 321 | * ret = drm_dev_register(drm); |
| 322 | * if (ret) |
| 323 | * return ret; |
| 324 | * |
| 325 | * drm_fbdev_generic_setup(drm, 32); |
| 326 | * |
| 327 | * return 0; |
| 328 | * } |
| 329 | * |
| 330 | * // This function is called before the devm_ resources are released |
| 331 | * static int driver_remove(struct platform_device *pdev) |
| 332 | * { |
| 333 | * struct drm_device *drm = platform_get_drvdata(pdev); |
| 334 | * |
| 335 | * drm_dev_unregister(drm); |
| 336 | * drm_atomic_helper_shutdown(drm) |
| 337 | * |
| 338 | * return 0; |
| 339 | * } |
| 340 | * |
| 341 | * // This function is called on kernel restart and shutdown |
| 342 | * static void driver_shutdown(struct platform_device *pdev) |
| 343 | * { |
| 344 | * drm_atomic_helper_shutdown(platform_get_drvdata(pdev)); |
| 345 | * } |
| 346 | * |
| 347 | * static int __maybe_unused driver_pm_suspend(struct device *dev) |
| 348 | * { |
| 349 | * return drm_mode_config_helper_suspend(dev_get_drvdata(dev)); |
| 350 | * } |
| 351 | * |
| 352 | * static int __maybe_unused driver_pm_resume(struct device *dev) |
| 353 | * { |
| 354 | * drm_mode_config_helper_resume(dev_get_drvdata(dev)); |
| 355 | * |
| 356 | * return 0; |
| 357 | * } |
| 358 | * |
| 359 | * static const struct dev_pm_ops driver_pm_ops = { |
| 360 | * SET_SYSTEM_SLEEP_PM_OPS(driver_pm_suspend, driver_pm_resume) |
| 361 | * }; |
| 362 | * |
| 363 | * static struct platform_driver driver_driver = { |
| 364 | * .driver = { |
| 365 | * [...] |
| 366 | * .pm = &driver_pm_ops, |
| 367 | * }, |
| 368 | * .probe = driver_probe, |
| 369 | * .remove = driver_remove, |
| 370 | * .shutdown = driver_shutdown, |
| 371 | * }; |
| 372 | * module_platform_driver(driver_driver); |
| 373 | * |
| 374 | * Drivers that want to support device unplugging (USB, DT overlay unload) should |
| 375 | * use drm_dev_unplug() instead of drm_dev_unregister(). The driver must protect |
| 376 | * regions that is accessing device resources to prevent use after they're |
| 377 | * released. This is done using drm_dev_enter() and drm_dev_exit(). There is one |
| 378 | * shortcoming however, drm_dev_unplug() marks the drm_device as unplugged before |
| 379 | * drm_atomic_helper_shutdown() is called. This means that if the disable code |
| 380 | * paths are protected, they will not run on regular driver module unload, |
| 381 | * possibily leaving the hardware enabled. |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 382 | */ |
| 383 | |
| 384 | /** |
| 385 | * drm_put_dev - Unregister and release a DRM device |
| 386 | * @dev: DRM device |
| 387 | * |
| 388 | * Called at module unload time or when a PCI device is unplugged. |
| 389 | * |
| 390 | * Cleans up all DRM device, calling drm_lastclose(). |
| 391 | * |
| 392 | * Note: Use of this function is deprecated. It will eventually go away |
| 393 | * completely. Please use drm_dev_unregister() and drm_dev_put() explicitly |
| 394 | * instead to make sure that the device isn't userspace accessible any more |
| 395 | * while teardown is in progress, ensuring that userspace can't access an |
| 396 | * inconsistent state. |
| 397 | */ |
| 398 | void drm_put_dev(struct drm_device *dev) |
| 399 | { |
| 400 | DRM_DEBUG("\n"); |
| 401 | |
| 402 | if (!dev) { |
| 403 | DRM_ERROR("cleanup called no dev\n"); |
| 404 | return; |
| 405 | } |
| 406 | |
| 407 | drm_dev_unregister(dev); |
| 408 | drm_dev_put(dev); |
| 409 | } |
| 410 | EXPORT_SYMBOL(drm_put_dev); |
| 411 | |
| 412 | /** |
| 413 | * drm_dev_enter - Enter device critical section |
| 414 | * @dev: DRM device |
| 415 | * @idx: Pointer to index that will be passed to the matching drm_dev_exit() |
| 416 | * |
| 417 | * This function marks and protects the beginning of a section that should not |
| 418 | * be entered after the device has been unplugged. The section end is marked |
| 419 | * with drm_dev_exit(). Calls to this function can be nested. |
| 420 | * |
| 421 | * Returns: |
| 422 | * True if it is OK to enter the section, false otherwise. |
| 423 | */ |
| 424 | bool drm_dev_enter(struct drm_device *dev, int *idx) |
| 425 | { |
| 426 | *idx = srcu_read_lock(&drm_unplug_srcu); |
| 427 | |
| 428 | if (dev->unplugged) { |
| 429 | srcu_read_unlock(&drm_unplug_srcu, *idx); |
| 430 | return false; |
| 431 | } |
| 432 | |
| 433 | return true; |
| 434 | } |
| 435 | EXPORT_SYMBOL(drm_dev_enter); |
| 436 | |
| 437 | /** |
| 438 | * drm_dev_exit - Exit device critical section |
| 439 | * @idx: index returned from drm_dev_enter() |
| 440 | * |
| 441 | * This function marks the end of a section that should not be entered after |
| 442 | * the device has been unplugged. |
| 443 | */ |
| 444 | void drm_dev_exit(int idx) |
| 445 | { |
| 446 | srcu_read_unlock(&drm_unplug_srcu, idx); |
| 447 | } |
| 448 | EXPORT_SYMBOL(drm_dev_exit); |
| 449 | |
| 450 | /** |
| 451 | * drm_dev_unplug - unplug a DRM device |
| 452 | * @dev: DRM device |
| 453 | * |
| 454 | * This unplugs a hotpluggable DRM device, which makes it inaccessible to |
| 455 | * userspace operations. Entry-points can use drm_dev_enter() and |
| 456 | * drm_dev_exit() to protect device resources in a race free manner. This |
| 457 | * essentially unregisters the device like drm_dev_unregister(), but can be |
| 458 | * called while there are still open users of @dev. |
| 459 | */ |
| 460 | void drm_dev_unplug(struct drm_device *dev) |
| 461 | { |
| 462 | /* |
| 463 | * After synchronizing any critical read section is guaranteed to see |
| 464 | * the new value of ->unplugged, and any critical section which might |
| 465 | * still have seen the old value of ->unplugged is guaranteed to have |
| 466 | * finished. |
| 467 | */ |
| 468 | dev->unplugged = true; |
| 469 | synchronize_srcu(&drm_unplug_srcu); |
| 470 | |
| 471 | drm_dev_unregister(dev); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 472 | } |
| 473 | EXPORT_SYMBOL(drm_dev_unplug); |
| 474 | |
| 475 | /* |
| 476 | * DRM internal mount |
| 477 | * We want to be able to allocate our own "struct address_space" to control |
| 478 | * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow |
| 479 | * stand-alone address_space objects, so we need an underlying inode. As there |
| 480 | * is no way to allocate an independent inode easily, we need a fake internal |
| 481 | * VFS mount-point. |
| 482 | * |
| 483 | * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free() |
| 484 | * frees it again. You are allowed to use iget() and iput() to get references to |
| 485 | * the inode. But each drm_fs_inode_new() call must be paired with exactly one |
| 486 | * drm_fs_inode_free() call (which does not have to be the last iput()). |
| 487 | * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it |
| 488 | * between multiple inode-users. You could, technically, call |
| 489 | * iget() + drm_fs_inode_free() directly after alloc and sometime later do an |
| 490 | * iput(), but this way you'd end up with a new vfsmount for each inode. |
| 491 | */ |
| 492 | |
| 493 | static int drm_fs_cnt; |
| 494 | static struct vfsmount *drm_fs_mnt; |
| 495 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 496 | static int drm_fs_init_fs_context(struct fs_context *fc) |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 497 | { |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 498 | return init_pseudo(fc, 0x010203ff) ? 0 : -ENOMEM; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 499 | } |
| 500 | |
| 501 | static struct file_system_type drm_fs_type = { |
| 502 | .name = "drm", |
| 503 | .owner = THIS_MODULE, |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 504 | .init_fs_context = drm_fs_init_fs_context, |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 505 | .kill_sb = kill_anon_super, |
| 506 | }; |
| 507 | |
| 508 | static struct inode *drm_fs_inode_new(void) |
| 509 | { |
| 510 | struct inode *inode; |
| 511 | int r; |
| 512 | |
| 513 | r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt); |
| 514 | if (r < 0) { |
| 515 | DRM_ERROR("Cannot mount pseudo fs: %d\n", r); |
| 516 | return ERR_PTR(r); |
| 517 | } |
| 518 | |
| 519 | inode = alloc_anon_inode(drm_fs_mnt->mnt_sb); |
| 520 | if (IS_ERR(inode)) |
| 521 | simple_release_fs(&drm_fs_mnt, &drm_fs_cnt); |
| 522 | |
| 523 | return inode; |
| 524 | } |
| 525 | |
| 526 | static void drm_fs_inode_free(struct inode *inode) |
| 527 | { |
| 528 | if (inode) { |
| 529 | iput(inode); |
| 530 | simple_release_fs(&drm_fs_mnt, &drm_fs_cnt); |
| 531 | } |
| 532 | } |
| 533 | |
| 534 | /** |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 535 | * DOC: component helper usage recommendations |
| 536 | * |
| 537 | * DRM drivers that drive hardware where a logical device consists of a pile of |
| 538 | * independent hardware blocks are recommended to use the :ref:`component helper |
| 539 | * library<component>`. For consistency and better options for code reuse the |
| 540 | * following guidelines apply: |
| 541 | * |
| 542 | * - The entire device initialization procedure should be run from the |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 543 | * &component_master_ops.master_bind callback, starting with |
| 544 | * devm_drm_dev_alloc(), then binding all components with |
| 545 | * component_bind_all() and finishing with drm_dev_register(). |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 546 | * |
| 547 | * - The opaque pointer passed to all components through component_bind_all() |
| 548 | * should point at &struct drm_device of the device instance, not some driver |
| 549 | * specific private structure. |
| 550 | * |
| 551 | * - The component helper fills the niche where further standardization of |
| 552 | * interfaces is not practical. When there already is, or will be, a |
| 553 | * standardized interface like &drm_bridge or &drm_panel, providing its own |
| 554 | * functions to find such components at driver load time, like |
| 555 | * drm_of_find_panel_or_bridge(), then the component helper should not be |
| 556 | * used. |
| 557 | */ |
| 558 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 559 | static void drm_dev_init_release(struct drm_device *dev, void *res) |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 560 | { |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 561 | drm_legacy_ctxbitmap_cleanup(dev); |
| 562 | drm_legacy_remove_map_hash(dev); |
| 563 | drm_fs_inode_free(dev->anon_inode); |
| 564 | |
| 565 | put_device(dev->dev); |
| 566 | /* Prevent use-after-free in drm_managed_release when debugging is |
| 567 | * enabled. Slightly awkward, but can't really be helped. */ |
| 568 | dev->dev = NULL; |
| 569 | mutex_destroy(&dev->master_mutex); |
| 570 | mutex_destroy(&dev->clientlist_mutex); |
| 571 | mutex_destroy(&dev->filelist_mutex); |
| 572 | mutex_destroy(&dev->struct_mutex); |
| 573 | drm_legacy_destroy_members(dev); |
| 574 | } |
| 575 | |
| 576 | static int drm_dev_init(struct drm_device *dev, |
| 577 | struct drm_driver *driver, |
| 578 | struct device *parent) |
| 579 | { |
| 580 | struct inode *inode; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 581 | int ret; |
| 582 | |
| 583 | if (!drm_core_init_complete) { |
| 584 | DRM_ERROR("DRM core is not initialized\n"); |
| 585 | return -ENODEV; |
| 586 | } |
| 587 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 588 | if (WARN_ON(!parent)) |
| 589 | return -EINVAL; |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 590 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 591 | kref_init(&dev->ref); |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 592 | dev->dev = get_device(parent); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 593 | dev->driver = driver; |
| 594 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 595 | INIT_LIST_HEAD(&dev->managed.resources); |
| 596 | spin_lock_init(&dev->managed.lock); |
| 597 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 598 | /* no per-device feature limits by default */ |
| 599 | dev->driver_features = ~0u; |
| 600 | |
| 601 | drm_legacy_init_members(dev); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 602 | INIT_LIST_HEAD(&dev->filelist); |
| 603 | INIT_LIST_HEAD(&dev->filelist_internal); |
| 604 | INIT_LIST_HEAD(&dev->clientlist); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 605 | INIT_LIST_HEAD(&dev->vblank_event_list); |
| 606 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 607 | spin_lock_init(&dev->event_lock); |
| 608 | mutex_init(&dev->struct_mutex); |
| 609 | mutex_init(&dev->filelist_mutex); |
| 610 | mutex_init(&dev->clientlist_mutex); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 611 | mutex_init(&dev->master_mutex); |
| 612 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 613 | ret = drmm_add_action(dev, drm_dev_init_release, NULL); |
| 614 | if (ret) |
| 615 | return ret; |
| 616 | |
| 617 | inode = drm_fs_inode_new(); |
| 618 | if (IS_ERR(inode)) { |
| 619 | ret = PTR_ERR(inode); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 620 | DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret); |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 621 | goto err; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 622 | } |
| 623 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 624 | dev->anon_inode = inode; |
| 625 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 626 | if (drm_core_check_feature(dev, DRIVER_RENDER)) { |
| 627 | ret = drm_minor_alloc(dev, DRM_MINOR_RENDER); |
| 628 | if (ret) |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 629 | goto err; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 630 | } |
| 631 | |
| 632 | ret = drm_minor_alloc(dev, DRM_MINOR_PRIMARY); |
| 633 | if (ret) |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 634 | goto err; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 635 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 636 | ret = drm_legacy_create_map_hash(dev); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 637 | if (ret) |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 638 | goto err; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 639 | |
| 640 | drm_legacy_ctxbitmap_init(dev); |
| 641 | |
| 642 | if (drm_core_check_feature(dev, DRIVER_GEM)) { |
| 643 | ret = drm_gem_init(dev); |
| 644 | if (ret) { |
| 645 | DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n"); |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 646 | goto err; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 647 | } |
| 648 | } |
| 649 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 650 | ret = drm_dev_set_unique(dev, dev_name(parent)); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 651 | if (ret) |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 652 | goto err; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 653 | |
| 654 | return 0; |
| 655 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 656 | err: |
| 657 | drm_managed_release(dev); |
| 658 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 659 | return ret; |
| 660 | } |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 661 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 662 | static void devm_drm_dev_init_release(void *data) |
| 663 | { |
| 664 | drm_dev_put(data); |
| 665 | } |
| 666 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 667 | static int devm_drm_dev_init(struct device *parent, |
| 668 | struct drm_device *dev, |
| 669 | struct drm_driver *driver) |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 670 | { |
| 671 | int ret; |
| 672 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 673 | ret = drm_dev_init(dev, driver, parent); |
| 674 | if (ret) |
| 675 | return ret; |
| 676 | |
| 677 | ret = devm_add_action(parent, devm_drm_dev_init_release, dev); |
| 678 | if (ret) |
| 679 | devm_drm_dev_init_release(dev); |
| 680 | |
| 681 | return ret; |
| 682 | } |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 683 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 684 | void *__devm_drm_dev_alloc(struct device *parent, struct drm_driver *driver, |
| 685 | size_t size, size_t offset) |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 686 | { |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 687 | void *container; |
| 688 | struct drm_device *drm; |
| 689 | int ret; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 690 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 691 | container = kzalloc(size, GFP_KERNEL); |
| 692 | if (!container) |
| 693 | return ERR_PTR(-ENOMEM); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 694 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 695 | drm = container + offset; |
| 696 | ret = devm_drm_dev_init(parent, drm, driver); |
| 697 | if (ret) { |
| 698 | kfree(container); |
| 699 | return ERR_PTR(ret); |
| 700 | } |
| 701 | drmm_add_final_kfree(drm, container); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 702 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 703 | return container; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 704 | } |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 705 | EXPORT_SYMBOL(__devm_drm_dev_alloc); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 706 | |
| 707 | /** |
| 708 | * drm_dev_alloc - Allocate new DRM device |
| 709 | * @driver: DRM driver to allocate device for |
| 710 | * @parent: Parent device object |
| 711 | * |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 712 | * This is the deprecated version of devm_drm_dev_alloc(), which does not support |
| 713 | * subclassing through embedding the struct &drm_device in a driver private |
| 714 | * structure, and which does not support automatic cleanup through devres. |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 715 | * |
| 716 | * RETURNS: |
| 717 | * Pointer to new DRM device, or ERR_PTR on failure. |
| 718 | */ |
| 719 | struct drm_device *drm_dev_alloc(struct drm_driver *driver, |
| 720 | struct device *parent) |
| 721 | { |
| 722 | struct drm_device *dev; |
| 723 | int ret; |
| 724 | |
| 725 | dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
| 726 | if (!dev) |
| 727 | return ERR_PTR(-ENOMEM); |
| 728 | |
| 729 | ret = drm_dev_init(dev, driver, parent); |
| 730 | if (ret) { |
| 731 | kfree(dev); |
| 732 | return ERR_PTR(ret); |
| 733 | } |
| 734 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 735 | drmm_add_final_kfree(dev, dev); |
| 736 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 737 | return dev; |
| 738 | } |
| 739 | EXPORT_SYMBOL(drm_dev_alloc); |
| 740 | |
| 741 | static void drm_dev_release(struct kref *ref) |
| 742 | { |
| 743 | struct drm_device *dev = container_of(ref, struct drm_device, ref); |
| 744 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 745 | if (dev->driver->release) |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 746 | dev->driver->release(dev); |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 747 | |
| 748 | drm_managed_release(dev); |
| 749 | |
| 750 | kfree(dev->managed.final_kfree); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 751 | } |
| 752 | |
| 753 | /** |
| 754 | * drm_dev_get - Take reference of a DRM device |
| 755 | * @dev: device to take reference of or NULL |
| 756 | * |
| 757 | * This increases the ref-count of @dev by one. You *must* already own a |
| 758 | * reference when calling this. Use drm_dev_put() to drop this reference |
| 759 | * again. |
| 760 | * |
| 761 | * This function never fails. However, this function does not provide *any* |
| 762 | * guarantee whether the device is alive or running. It only provides a |
| 763 | * reference to the object and the memory associated with it. |
| 764 | */ |
| 765 | void drm_dev_get(struct drm_device *dev) |
| 766 | { |
| 767 | if (dev) |
| 768 | kref_get(&dev->ref); |
| 769 | } |
| 770 | EXPORT_SYMBOL(drm_dev_get); |
| 771 | |
| 772 | /** |
| 773 | * drm_dev_put - Drop reference of a DRM device |
| 774 | * @dev: device to drop reference of or NULL |
| 775 | * |
| 776 | * This decreases the ref-count of @dev by one. The device is destroyed if the |
| 777 | * ref-count drops to zero. |
| 778 | */ |
| 779 | void drm_dev_put(struct drm_device *dev) |
| 780 | { |
| 781 | if (dev) |
| 782 | kref_put(&dev->ref, drm_dev_release); |
| 783 | } |
| 784 | EXPORT_SYMBOL(drm_dev_put); |
| 785 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 786 | static int create_compat_control_link(struct drm_device *dev) |
| 787 | { |
| 788 | struct drm_minor *minor; |
| 789 | char *name; |
| 790 | int ret; |
| 791 | |
| 792 | if (!drm_core_check_feature(dev, DRIVER_MODESET)) |
| 793 | return 0; |
| 794 | |
| 795 | minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY); |
| 796 | if (!minor) |
| 797 | return 0; |
| 798 | |
| 799 | /* |
| 800 | * Some existing userspace out there uses the existing of the controlD* |
| 801 | * sysfs files to figure out whether it's a modeset driver. It only does |
| 802 | * readdir, hence a symlink is sufficient (and the least confusing |
| 803 | * option). Otherwise controlD* is entirely unused. |
| 804 | * |
| 805 | * Old controlD chardev have been allocated in the range |
| 806 | * 64-127. |
| 807 | */ |
| 808 | name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64); |
| 809 | if (!name) |
| 810 | return -ENOMEM; |
| 811 | |
| 812 | ret = sysfs_create_link(minor->kdev->kobj.parent, |
| 813 | &minor->kdev->kobj, |
| 814 | name); |
| 815 | |
| 816 | kfree(name); |
| 817 | |
| 818 | return ret; |
| 819 | } |
| 820 | |
| 821 | static void remove_compat_control_link(struct drm_device *dev) |
| 822 | { |
| 823 | struct drm_minor *minor; |
| 824 | char *name; |
| 825 | |
| 826 | if (!drm_core_check_feature(dev, DRIVER_MODESET)) |
| 827 | return; |
| 828 | |
| 829 | minor = *drm_minor_get_slot(dev, DRM_MINOR_PRIMARY); |
| 830 | if (!minor) |
| 831 | return; |
| 832 | |
| 833 | name = kasprintf(GFP_KERNEL, "controlD%d", minor->index + 64); |
| 834 | if (!name) |
| 835 | return; |
| 836 | |
| 837 | sysfs_remove_link(minor->kdev->kobj.parent, name); |
| 838 | |
| 839 | kfree(name); |
| 840 | } |
| 841 | |
| 842 | /** |
| 843 | * drm_dev_register - Register DRM device |
| 844 | * @dev: Device to register |
| 845 | * @flags: Flags passed to the driver's .load() function |
| 846 | * |
| 847 | * Register the DRM device @dev with the system, advertise device to user-space |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 848 | * and start normal device operation. @dev must be initialized via drm_dev_init() |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 849 | * previously. |
| 850 | * |
| 851 | * Never call this twice on any device! |
| 852 | * |
| 853 | * NOTE: To ensure backward compatibility with existing drivers method this |
| 854 | * function calls the &drm_driver.load method after registering the device |
| 855 | * nodes, creating race conditions. Usage of the &drm_driver.load methods is |
| 856 | * therefore deprecated, drivers must perform all initialization before calling |
| 857 | * drm_dev_register(). |
| 858 | * |
| 859 | * RETURNS: |
| 860 | * 0 on success, negative error code on failure. |
| 861 | */ |
| 862 | int drm_dev_register(struct drm_device *dev, unsigned long flags) |
| 863 | { |
| 864 | struct drm_driver *driver = dev->driver; |
| 865 | int ret; |
| 866 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 867 | if (!driver->load) |
| 868 | drm_mode_config_validate(dev); |
| 869 | |
| 870 | WARN_ON(!dev->managed.final_kfree); |
| 871 | |
| 872 | if (drm_dev_needs_global_mutex(dev)) |
| 873 | mutex_lock(&drm_global_mutex); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 874 | |
| 875 | ret = drm_minor_register(dev, DRM_MINOR_RENDER); |
| 876 | if (ret) |
| 877 | goto err_minors; |
| 878 | |
| 879 | ret = drm_minor_register(dev, DRM_MINOR_PRIMARY); |
| 880 | if (ret) |
| 881 | goto err_minors; |
| 882 | |
| 883 | ret = create_compat_control_link(dev); |
| 884 | if (ret) |
| 885 | goto err_minors; |
| 886 | |
| 887 | dev->registered = true; |
| 888 | |
| 889 | if (dev->driver->load) { |
| 890 | ret = dev->driver->load(dev, flags); |
| 891 | if (ret) |
| 892 | goto err_minors; |
| 893 | } |
| 894 | |
| 895 | if (drm_core_check_feature(dev, DRIVER_MODESET)) |
| 896 | drm_modeset_register_all(dev); |
| 897 | |
| 898 | ret = 0; |
| 899 | |
| 900 | DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n", |
| 901 | driver->name, driver->major, driver->minor, |
| 902 | driver->patchlevel, driver->date, |
| 903 | dev->dev ? dev_name(dev->dev) : "virtual device", |
| 904 | dev->primary->index); |
| 905 | |
| 906 | goto out_unlock; |
| 907 | |
| 908 | err_minors: |
| 909 | remove_compat_control_link(dev); |
| 910 | drm_minor_unregister(dev, DRM_MINOR_PRIMARY); |
| 911 | drm_minor_unregister(dev, DRM_MINOR_RENDER); |
| 912 | out_unlock: |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 913 | if (drm_dev_needs_global_mutex(dev)) |
| 914 | mutex_unlock(&drm_global_mutex); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 915 | return ret; |
| 916 | } |
| 917 | EXPORT_SYMBOL(drm_dev_register); |
| 918 | |
| 919 | /** |
| 920 | * drm_dev_unregister - Unregister DRM device |
| 921 | * @dev: Device to unregister |
| 922 | * |
| 923 | * Unregister the DRM device from the system. This does the reverse of |
| 924 | * drm_dev_register() but does not deallocate the device. The caller must call |
| 925 | * drm_dev_put() to drop their final reference. |
| 926 | * |
| 927 | * A special form of unregistering for hotpluggable devices is drm_dev_unplug(), |
| 928 | * which can be called while there are still open users of @dev. |
| 929 | * |
| 930 | * This should be called first in the device teardown code to make sure |
| 931 | * userspace can't access the device instance any more. |
| 932 | */ |
| 933 | void drm_dev_unregister(struct drm_device *dev) |
| 934 | { |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 935 | if (drm_core_check_feature(dev, DRIVER_LEGACY)) |
| 936 | drm_lastclose(dev); |
| 937 | |
| 938 | dev->registered = false; |
| 939 | |
| 940 | drm_client_dev_unregister(dev); |
| 941 | |
| 942 | if (drm_core_check_feature(dev, DRIVER_MODESET)) |
| 943 | drm_modeset_unregister_all(dev); |
| 944 | |
| 945 | if (dev->driver->unload) |
| 946 | dev->driver->unload(dev); |
| 947 | |
| 948 | if (dev->agp) |
| 949 | drm_pci_agp_destroy(dev); |
| 950 | |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 951 | drm_legacy_rmmaps(dev); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 952 | |
| 953 | remove_compat_control_link(dev); |
| 954 | drm_minor_unregister(dev, DRM_MINOR_PRIMARY); |
| 955 | drm_minor_unregister(dev, DRM_MINOR_RENDER); |
| 956 | } |
| 957 | EXPORT_SYMBOL(drm_dev_unregister); |
| 958 | |
| 959 | /** |
| 960 | * drm_dev_set_unique - Set the unique name of a DRM device |
| 961 | * @dev: device of which to set the unique name |
| 962 | * @name: unique name |
| 963 | * |
David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame] | 964 | * Sets the unique name of a DRM device using the specified string. This is |
| 965 | * already done by drm_dev_init(), drivers should only override the default |
| 966 | * unique name for backwards compatibility reasons. |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 967 | * |
| 968 | * Return: 0 on success or a negative error code on failure. |
| 969 | */ |
| 970 | int drm_dev_set_unique(struct drm_device *dev, const char *name) |
| 971 | { |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 972 | drmm_kfree(dev, dev->unique); |
| 973 | dev->unique = drmm_kstrdup(dev, name, GFP_KERNEL); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 974 | |
| 975 | return dev->unique ? 0 : -ENOMEM; |
| 976 | } |
| 977 | EXPORT_SYMBOL(drm_dev_set_unique); |
| 978 | |
| 979 | /* |
| 980 | * DRM Core |
| 981 | * The DRM core module initializes all global DRM objects and makes them |
| 982 | * available to drivers. Once setup, drivers can probe their respective |
| 983 | * devices. |
| 984 | * Currently, core management includes: |
| 985 | * - The "DRM-Global" key/value database |
| 986 | * - Global ID management for connectors |
| 987 | * - DRM major number allocation |
| 988 | * - DRM minor management |
| 989 | * - DRM sysfs class |
| 990 | * - DRM debugfs root |
| 991 | * |
| 992 | * Furthermore, the DRM core provides dynamic char-dev lookups. For each |
| 993 | * interface registered on a DRM device, you can request minor numbers from DRM |
| 994 | * core. DRM core takes care of major-number management and char-dev |
| 995 | * registration. A stub ->open() callback forwards any open() requests to the |
| 996 | * registered minor. |
| 997 | */ |
| 998 | |
| 999 | static int drm_stub_open(struct inode *inode, struct file *filp) |
| 1000 | { |
| 1001 | const struct file_operations *new_fops; |
| 1002 | struct drm_minor *minor; |
| 1003 | int err; |
| 1004 | |
| 1005 | DRM_DEBUG("\n"); |
| 1006 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1007 | minor = drm_minor_acquire(iminor(inode)); |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 1008 | if (IS_ERR(minor)) |
| 1009 | return PTR_ERR(minor); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1010 | |
| 1011 | new_fops = fops_get(minor->dev->driver->fops); |
| 1012 | if (!new_fops) { |
| 1013 | err = -ENODEV; |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 1014 | goto out; |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1015 | } |
| 1016 | |
| 1017 | replace_fops(filp, new_fops); |
| 1018 | if (filp->f_op->open) |
| 1019 | err = filp->f_op->open(inode, filp); |
| 1020 | else |
| 1021 | err = 0; |
| 1022 | |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 1023 | out: |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1024 | drm_minor_release(minor); |
Olivier Deprez | 157378f | 2022-04-04 15:47:50 +0200 | [diff] [blame^] | 1025 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1026 | return err; |
| 1027 | } |
| 1028 | |
| 1029 | static const struct file_operations drm_stub_fops = { |
| 1030 | .owner = THIS_MODULE, |
| 1031 | .open = drm_stub_open, |
| 1032 | .llseek = noop_llseek, |
| 1033 | }; |
| 1034 | |
| 1035 | static void drm_core_exit(void) |
| 1036 | { |
| 1037 | unregister_chrdev(DRM_MAJOR, "drm"); |
| 1038 | debugfs_remove(drm_debugfs_root); |
| 1039 | drm_sysfs_destroy(); |
| 1040 | idr_destroy(&drm_minors_idr); |
| 1041 | drm_connector_ida_destroy(); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1042 | } |
| 1043 | |
| 1044 | static int __init drm_core_init(void) |
| 1045 | { |
| 1046 | int ret; |
| 1047 | |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1048 | drm_connector_ida_init(); |
| 1049 | idr_init(&drm_minors_idr); |
| 1050 | |
| 1051 | ret = drm_sysfs_init(); |
| 1052 | if (ret < 0) { |
| 1053 | DRM_ERROR("Cannot create DRM class: %d\n", ret); |
| 1054 | goto error; |
| 1055 | } |
| 1056 | |
| 1057 | drm_debugfs_root = debugfs_create_dir("dri", NULL); |
Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1058 | |
| 1059 | ret = register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops); |
| 1060 | if (ret < 0) |
| 1061 | goto error; |
| 1062 | |
| 1063 | drm_core_init_complete = true; |
| 1064 | |
| 1065 | DRM_DEBUG("Initialized\n"); |
| 1066 | return 0; |
| 1067 | |
| 1068 | error: |
| 1069 | drm_core_exit(); |
| 1070 | return ret; |
| 1071 | } |
| 1072 | |
| 1073 | module_init(drm_core_init); |
| 1074 | module_exit(drm_core_exit); |