1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2016 Noralf Trønnes
6 #include <linux/module.h>
7 #include <linux/slab.h>
9 #include <drm/drm_atomic.h>
10 #include <drm/drm_atomic_helper.h>
11 #include <drm/drm_bridge.h>
12 #include <drm/drm_managed.h>
13 #include <drm/drm_plane_helper.h>
14 #include <drm/drm_probe_helper.h>
15 #include <drm/drm_simple_kms_helper.h>
20 * This helper library provides helpers for drivers for simple display
23 * drm_simple_display_pipe_init() initializes a simple display pipeline
24 * which has only one full-screen scanout buffer feeding one output. The
25 * pipeline is represented by &struct drm_simple_display_pipe and binds
26 * together &drm_plane, &drm_crtc and &drm_encoder structures into one fixed
27 * entity. Some flexibility for code reuse is provided through a separately
28 * allocated &drm_connector object and supporting optional &drm_bridge
31 * Many drivers require only a very simple encoder that fulfills the minimum
32 * requirements of the display pipeline and does not add additional
33 * functionality. The function drm_simple_encoder_init() provides an
34 * implementation of such an encoder.
37 static const struct drm_encoder_funcs drm_simple_encoder_funcs_cleanup = {
38 .destroy = drm_encoder_cleanup,
42 * drm_simple_encoder_init - Initialize a preallocated encoder with
43 * basic functionality.
45 * @encoder: the encoder to initialize
46 * @encoder_type: user visible type of the encoder
48 * Initialises a preallocated encoder that has no further functionality.
49 * Settings for possible CRTC and clones are left to their initial values.
50 * The encoder will be cleaned up automatically as part of the mode-setting
53 * The caller of drm_simple_encoder_init() is responsible for freeing
54 * the encoder's memory after the encoder has been cleaned up. At the
55 * moment this only works reliably if the encoder data structure is
56 * stored in the device structure. Free the encoder's memory as part of
57 * the device release function.
59 * Note: consider using drmm_simple_encoder_alloc() instead of
60 * drm_simple_encoder_init() to let the DRM managed resource infrastructure
61 * take care of cleanup and deallocation.
64 * Zero on success, error code on failure.
66 int drm_simple_encoder_init(struct drm_device *dev,
67 struct drm_encoder *encoder,
70 return drm_encoder_init(dev, encoder,
71 &drm_simple_encoder_funcs_cleanup,
74 EXPORT_SYMBOL(drm_simple_encoder_init);
76 void *__drmm_simple_encoder_alloc(struct drm_device *dev, size_t size,
77 size_t offset, int encoder_type)
79 return __drmm_encoder_alloc(dev, size, offset, NULL, encoder_type,
82 EXPORT_SYMBOL(__drmm_simple_encoder_alloc);
84 static enum drm_mode_status
85 drm_simple_kms_crtc_mode_valid(struct drm_crtc *crtc,
86 const struct drm_display_mode *mode)
88 struct drm_simple_display_pipe *pipe;
90 pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
91 if (!pipe->funcs || !pipe->funcs->mode_valid)
95 return pipe->funcs->mode_valid(pipe, mode);
98 static int drm_simple_kms_crtc_check(struct drm_crtc *crtc,
99 struct drm_atomic_state *state)
101 struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
103 bool has_primary = crtc_state->plane_mask &
104 drm_plane_mask(crtc->primary);
106 /* We always want to have an active plane with an active CRTC */
107 if (has_primary != crtc_state->enable)
110 return drm_atomic_add_affected_planes(state, crtc);
113 static void drm_simple_kms_crtc_enable(struct drm_crtc *crtc,
114 struct drm_atomic_state *state)
116 struct drm_plane *plane;
117 struct drm_simple_display_pipe *pipe;
119 pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
120 if (!pipe->funcs || !pipe->funcs->enable)
123 plane = &pipe->plane;
124 pipe->funcs->enable(pipe, crtc->state, plane->state);
127 static void drm_simple_kms_crtc_disable(struct drm_crtc *crtc,
128 struct drm_atomic_state *state)
130 struct drm_simple_display_pipe *pipe;
132 pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
133 if (!pipe->funcs || !pipe->funcs->disable)
136 pipe->funcs->disable(pipe);
139 static const struct drm_crtc_helper_funcs drm_simple_kms_crtc_helper_funcs = {
140 .mode_valid = drm_simple_kms_crtc_mode_valid,
141 .atomic_check = drm_simple_kms_crtc_check,
142 .atomic_enable = drm_simple_kms_crtc_enable,
143 .atomic_disable = drm_simple_kms_crtc_disable,
146 static int drm_simple_kms_crtc_enable_vblank(struct drm_crtc *crtc)
148 struct drm_simple_display_pipe *pipe;
150 pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
151 if (!pipe->funcs || !pipe->funcs->enable_vblank)
154 return pipe->funcs->enable_vblank(pipe);
157 static void drm_simple_kms_crtc_disable_vblank(struct drm_crtc *crtc)
159 struct drm_simple_display_pipe *pipe;
161 pipe = container_of(crtc, struct drm_simple_display_pipe, crtc);
162 if (!pipe->funcs || !pipe->funcs->disable_vblank)
165 pipe->funcs->disable_vblank(pipe);
168 static const struct drm_crtc_funcs drm_simple_kms_crtc_funcs = {
169 .reset = drm_atomic_helper_crtc_reset,
170 .destroy = drm_crtc_cleanup,
171 .set_config = drm_atomic_helper_set_config,
172 .page_flip = drm_atomic_helper_page_flip,
173 .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
174 .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
175 .enable_vblank = drm_simple_kms_crtc_enable_vblank,
176 .disable_vblank = drm_simple_kms_crtc_disable_vblank,
179 static int drm_simple_kms_plane_atomic_check(struct drm_plane *plane,
180 struct drm_atomic_state *state)
182 struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state,
184 struct drm_simple_display_pipe *pipe;
185 struct drm_crtc_state *crtc_state;
188 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
189 crtc_state = drm_atomic_get_new_crtc_state(state,
192 ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state,
193 DRM_PLANE_HELPER_NO_SCALING,
194 DRM_PLANE_HELPER_NO_SCALING,
199 if (!plane_state->visible)
202 if (!pipe->funcs || !pipe->funcs->check)
205 return pipe->funcs->check(pipe, plane_state, crtc_state);
208 static void drm_simple_kms_plane_atomic_update(struct drm_plane *plane,
209 struct drm_atomic_state *state)
211 struct drm_plane_state *old_pstate = drm_atomic_get_old_plane_state(state,
213 struct drm_simple_display_pipe *pipe;
215 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
216 if (!pipe->funcs || !pipe->funcs->update)
219 pipe->funcs->update(pipe, old_pstate);
222 static int drm_simple_kms_plane_prepare_fb(struct drm_plane *plane,
223 struct drm_plane_state *state)
225 struct drm_simple_display_pipe *pipe;
227 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
228 if (!pipe->funcs || !pipe->funcs->prepare_fb)
231 return pipe->funcs->prepare_fb(pipe, state);
234 static void drm_simple_kms_plane_cleanup_fb(struct drm_plane *plane,
235 struct drm_plane_state *state)
237 struct drm_simple_display_pipe *pipe;
239 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
240 if (!pipe->funcs || !pipe->funcs->cleanup_fb)
243 pipe->funcs->cleanup_fb(pipe, state);
246 static bool drm_simple_kms_format_mod_supported(struct drm_plane *plane,
250 return modifier == DRM_FORMAT_MOD_LINEAR;
253 static const struct drm_plane_helper_funcs drm_simple_kms_plane_helper_funcs = {
254 .prepare_fb = drm_simple_kms_plane_prepare_fb,
255 .cleanup_fb = drm_simple_kms_plane_cleanup_fb,
256 .atomic_check = drm_simple_kms_plane_atomic_check,
257 .atomic_update = drm_simple_kms_plane_atomic_update,
260 static void drm_simple_kms_plane_reset(struct drm_plane *plane)
262 struct drm_simple_display_pipe *pipe;
264 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
265 if (!pipe->funcs || !pipe->funcs->reset_plane)
266 return drm_atomic_helper_plane_reset(plane);
268 return pipe->funcs->reset_plane(pipe);
271 static struct drm_plane_state *drm_simple_kms_plane_duplicate_state(struct drm_plane *plane)
273 struct drm_simple_display_pipe *pipe;
275 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
276 if (!pipe->funcs || !pipe->funcs->duplicate_plane_state)
277 return drm_atomic_helper_plane_duplicate_state(plane);
279 return pipe->funcs->duplicate_plane_state(pipe);
282 static void drm_simple_kms_plane_destroy_state(struct drm_plane *plane,
283 struct drm_plane_state *state)
285 struct drm_simple_display_pipe *pipe;
287 pipe = container_of(plane, struct drm_simple_display_pipe, plane);
288 if (!pipe->funcs || !pipe->funcs->destroy_plane_state)
289 drm_atomic_helper_plane_destroy_state(plane, state);
291 pipe->funcs->destroy_plane_state(pipe, state);
294 static const struct drm_plane_funcs drm_simple_kms_plane_funcs = {
295 .update_plane = drm_atomic_helper_update_plane,
296 .disable_plane = drm_atomic_helper_disable_plane,
297 .destroy = drm_plane_cleanup,
298 .reset = drm_simple_kms_plane_reset,
299 .atomic_duplicate_state = drm_simple_kms_plane_duplicate_state,
300 .atomic_destroy_state = drm_simple_kms_plane_destroy_state,
301 .format_mod_supported = drm_simple_kms_format_mod_supported,
305 * drm_simple_display_pipe_attach_bridge - Attach a bridge to the display pipe
306 * @pipe: simple display pipe object
307 * @bridge: bridge to attach
309 * Makes it possible to still use the drm_simple_display_pipe helpers when
310 * a DRM bridge has to be used.
312 * Note that you probably want to initialize the pipe by passing a NULL
313 * connector to drm_simple_display_pipe_init().
316 * Zero on success, negative error code on failure.
318 int drm_simple_display_pipe_attach_bridge(struct drm_simple_display_pipe *pipe,
319 struct drm_bridge *bridge)
321 return drm_bridge_attach(&pipe->encoder, bridge, NULL, 0);
323 EXPORT_SYMBOL(drm_simple_display_pipe_attach_bridge);
326 * drm_simple_display_pipe_init - Initialize a simple display pipeline
328 * @pipe: simple display pipe object to initialize
329 * @funcs: callbacks for the display pipe (optional)
330 * @formats: array of supported formats (DRM_FORMAT\_\*)
331 * @format_count: number of elements in @formats
332 * @format_modifiers: array of formats modifiers
333 * @connector: connector to attach and register (optional)
335 * Sets up a display pipeline which consist of a really simple
336 * plane-crtc-encoder pipe.
338 * If a connector is supplied, the pipe will be coupled with the provided
339 * connector. You may supply a NULL connector when using drm bridges, that
340 * handle connectors themselves (see drm_simple_display_pipe_attach_bridge()).
342 * Teardown of a simple display pipe is all handled automatically by the drm
343 * core through calling drm_mode_config_cleanup(). Drivers afterwards need to
344 * release the memory for the structure themselves.
347 * Zero on success, negative error code on failure.
349 int drm_simple_display_pipe_init(struct drm_device *dev,
350 struct drm_simple_display_pipe *pipe,
351 const struct drm_simple_display_pipe_funcs *funcs,
352 const uint32_t *formats, unsigned int format_count,
353 const uint64_t *format_modifiers,
354 struct drm_connector *connector)
356 struct drm_encoder *encoder = &pipe->encoder;
357 struct drm_plane *plane = &pipe->plane;
358 struct drm_crtc *crtc = &pipe->crtc;
361 pipe->connector = connector;
364 drm_plane_helper_add(plane, &drm_simple_kms_plane_helper_funcs);
365 ret = drm_universal_plane_init(dev, plane, 0,
366 &drm_simple_kms_plane_funcs,
367 formats, format_count,
369 DRM_PLANE_TYPE_PRIMARY, NULL);
373 drm_crtc_helper_add(crtc, &drm_simple_kms_crtc_helper_funcs);
374 ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
375 &drm_simple_kms_crtc_funcs, NULL);
379 encoder->possible_crtcs = drm_crtc_mask(crtc);
380 ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_NONE);
381 if (ret || !connector)
384 return drm_connector_attach_encoder(connector, encoder);
386 EXPORT_SYMBOL(drm_simple_display_pipe_init);
388 MODULE_LICENSE("GPL");