omap_crtc.c 16 KB

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  1. /*
  2. * drivers/gpu/drm/omapdrm/omap_crtc.c
  3. *
  4. * Copyright (C) 2011 Texas Instruments
  5. * Author: Rob Clark <rob@ti.com>
  6. *
  7. * This program is free software; you can redistribute it and/or modify it
  8. * under the terms of the GNU General Public License version 2 as published by
  9. * the Free Software Foundation.
  10. *
  11. * This program is distributed in the hope that it will be useful, but WITHOUT
  12. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  14. * more details.
  15. *
  16. * You should have received a copy of the GNU General Public License along with
  17. * this program. If not, see <http://www.gnu.org/licenses/>.
  18. */
  19. #include <linux/completion.h>
  20. #include <drm/drm_atomic.h>
  21. #include <drm/drm_atomic_helper.h>
  22. #include <drm/drm_crtc.h>
  23. #include <drm/drm_crtc_helper.h>
  24. #include <drm/drm_mode.h>
  25. #include <drm/drm_plane_helper.h>
  26. #include "omap_drv.h"
  27. #define to_omap_crtc(x) container_of(x, struct omap_crtc, base)
  28. struct omap_crtc {
  29. struct drm_crtc base;
  30. const char *name;
  31. enum omap_channel channel;
  32. struct drm_encoder *current_encoder;
  33. /*
  34. * Temporary: eventually this will go away, but it is needed
  35. * for now to keep the output's happy. (They only need
  36. * mgr->id.) Eventually this will be replaced w/ something
  37. * more common-panel-framework-y
  38. */
  39. struct omap_overlay_manager *mgr;
  40. struct omap_video_timings timings;
  41. struct omap_drm_irq vblank_irq;
  42. struct omap_drm_irq error_irq;
  43. /* pending event */
  44. struct drm_pending_vblank_event *event;
  45. wait_queue_head_t flip_wait;
  46. struct completion completion;
  47. bool ignore_digit_sync_lost;
  48. };
  49. /* -----------------------------------------------------------------------------
  50. * Helper Functions
  51. */
  52. uint32_t pipe2vbl(struct drm_crtc *crtc)
  53. {
  54. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  55. return dispc_mgr_get_vsync_irq(omap_crtc->channel);
  56. }
  57. const struct omap_video_timings *omap_crtc_timings(struct drm_crtc *crtc)
  58. {
  59. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  60. return &omap_crtc->timings;
  61. }
  62. enum omap_channel omap_crtc_channel(struct drm_crtc *crtc)
  63. {
  64. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  65. return omap_crtc->channel;
  66. }
  67. /* -----------------------------------------------------------------------------
  68. * DSS Manager Functions
  69. */
  70. /*
  71. * Manager-ops, callbacks from output when they need to configure
  72. * the upstream part of the video pipe.
  73. *
  74. * Most of these we can ignore until we add support for command-mode
  75. * panels.. for video-mode the crtc-helpers already do an adequate
  76. * job of sequencing the setup of the video pipe in the proper order
  77. */
  78. /* ovl-mgr-id -> crtc */
  79. static struct omap_crtc *omap_crtcs[8];
  80. /* we can probably ignore these until we support command-mode panels: */
  81. static int omap_crtc_dss_connect(struct omap_overlay_manager *mgr,
  82. struct omap_dss_device *dst)
  83. {
  84. if (mgr->output)
  85. return -EINVAL;
  86. if ((mgr->supported_outputs & dst->id) == 0)
  87. return -EINVAL;
  88. dst->manager = mgr;
  89. mgr->output = dst;
  90. return 0;
  91. }
  92. static void omap_crtc_dss_disconnect(struct omap_overlay_manager *mgr,
  93. struct omap_dss_device *dst)
  94. {
  95. mgr->output->manager = NULL;
  96. mgr->output = NULL;
  97. }
  98. static void omap_crtc_dss_start_update(struct omap_overlay_manager *mgr)
  99. {
  100. }
  101. /* Called only from omap_crtc_encoder_setup and suspend/resume handlers. */
  102. static void omap_crtc_set_enabled(struct drm_crtc *crtc, bool enable)
  103. {
  104. struct drm_device *dev = crtc->dev;
  105. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  106. enum omap_channel channel = omap_crtc->channel;
  107. struct omap_irq_wait *wait;
  108. u32 framedone_irq, vsync_irq;
  109. int ret;
  110. if (dispc_mgr_is_enabled(channel) == enable)
  111. return;
  112. if (omap_crtc->channel == OMAP_DSS_CHANNEL_DIGIT) {
  113. /*
  114. * Digit output produces some sync lost interrupts during the
  115. * first frame when enabling, so we need to ignore those.
  116. */
  117. omap_crtc->ignore_digit_sync_lost = true;
  118. }
  119. framedone_irq = dispc_mgr_get_framedone_irq(channel);
  120. vsync_irq = dispc_mgr_get_vsync_irq(channel);
  121. if (enable) {
  122. wait = omap_irq_wait_init(dev, vsync_irq, 1);
  123. } else {
  124. /*
  125. * When we disable the digit output, we need to wait for
  126. * FRAMEDONE to know that DISPC has finished with the output.
  127. *
  128. * OMAP2/3 does not have FRAMEDONE irq for digit output, and in
  129. * that case we need to use vsync interrupt, and wait for both
  130. * even and odd frames.
  131. */
  132. if (framedone_irq)
  133. wait = omap_irq_wait_init(dev, framedone_irq, 1);
  134. else
  135. wait = omap_irq_wait_init(dev, vsync_irq, 2);
  136. }
  137. dispc_mgr_enable(channel, enable);
  138. ret = omap_irq_wait(dev, wait, msecs_to_jiffies(100));
  139. if (ret) {
  140. dev_err(dev->dev, "%s: timeout waiting for %s\n",
  141. omap_crtc->name, enable ? "enable" : "disable");
  142. }
  143. if (omap_crtc->channel == OMAP_DSS_CHANNEL_DIGIT) {
  144. omap_crtc->ignore_digit_sync_lost = false;
  145. /* make sure the irq handler sees the value above */
  146. mb();
  147. }
  148. }
  149. static int omap_crtc_dss_enable(struct omap_overlay_manager *mgr)
  150. {
  151. struct omap_crtc *omap_crtc = omap_crtcs[mgr->id];
  152. struct omap_overlay_manager_info info;
  153. memset(&info, 0, sizeof(info));
  154. info.default_color = 0x00000000;
  155. info.trans_key = 0x00000000;
  156. info.trans_key_type = OMAP_DSS_COLOR_KEY_GFX_DST;
  157. info.trans_enabled = false;
  158. dispc_mgr_setup(omap_crtc->channel, &info);
  159. dispc_mgr_set_timings(omap_crtc->channel,
  160. &omap_crtc->timings);
  161. omap_crtc_set_enabled(&omap_crtc->base, true);
  162. return 0;
  163. }
  164. static void omap_crtc_dss_disable(struct omap_overlay_manager *mgr)
  165. {
  166. struct omap_crtc *omap_crtc = omap_crtcs[mgr->id];
  167. omap_crtc_set_enabled(&omap_crtc->base, false);
  168. }
  169. static void omap_crtc_dss_set_timings(struct omap_overlay_manager *mgr,
  170. const struct omap_video_timings *timings)
  171. {
  172. struct omap_crtc *omap_crtc = omap_crtcs[mgr->id];
  173. DBG("%s", omap_crtc->name);
  174. omap_crtc->timings = *timings;
  175. }
  176. static void omap_crtc_dss_set_lcd_config(struct omap_overlay_manager *mgr,
  177. const struct dss_lcd_mgr_config *config)
  178. {
  179. struct omap_crtc *omap_crtc = omap_crtcs[mgr->id];
  180. DBG("%s", omap_crtc->name);
  181. dispc_mgr_set_lcd_config(omap_crtc->channel, config);
  182. }
  183. static int omap_crtc_dss_register_framedone(
  184. struct omap_overlay_manager *mgr,
  185. void (*handler)(void *), void *data)
  186. {
  187. return 0;
  188. }
  189. static void omap_crtc_dss_unregister_framedone(
  190. struct omap_overlay_manager *mgr,
  191. void (*handler)(void *), void *data)
  192. {
  193. }
  194. static const struct dss_mgr_ops mgr_ops = {
  195. .connect = omap_crtc_dss_connect,
  196. .disconnect = omap_crtc_dss_disconnect,
  197. .start_update = omap_crtc_dss_start_update,
  198. .enable = omap_crtc_dss_enable,
  199. .disable = omap_crtc_dss_disable,
  200. .set_timings = omap_crtc_dss_set_timings,
  201. .set_lcd_config = omap_crtc_dss_set_lcd_config,
  202. .register_framedone_handler = omap_crtc_dss_register_framedone,
  203. .unregister_framedone_handler = omap_crtc_dss_unregister_framedone,
  204. };
  205. /* -----------------------------------------------------------------------------
  206. * Setup, Flush and Page Flip
  207. */
  208. static void omap_crtc_complete_page_flip(struct drm_crtc *crtc)
  209. {
  210. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  211. struct drm_pending_vblank_event *event;
  212. struct drm_device *dev = crtc->dev;
  213. unsigned long flags;
  214. spin_lock_irqsave(&dev->event_lock, flags);
  215. event = omap_crtc->event;
  216. omap_crtc->event = NULL;
  217. if (event) {
  218. list_del(&event->base.link);
  219. /*
  220. * Queue the event for delivery if it's still linked to a file
  221. * handle, otherwise just destroy it.
  222. */
  223. if (event->base.file_priv)
  224. drm_crtc_send_vblank_event(crtc, event);
  225. else
  226. event->base.destroy(&event->base);
  227. wake_up(&omap_crtc->flip_wait);
  228. drm_crtc_vblank_put(crtc);
  229. }
  230. spin_unlock_irqrestore(&dev->event_lock, flags);
  231. }
  232. static bool omap_crtc_page_flip_pending(struct drm_crtc *crtc)
  233. {
  234. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  235. struct drm_device *dev = crtc->dev;
  236. unsigned long flags;
  237. bool pending;
  238. spin_lock_irqsave(&dev->event_lock, flags);
  239. pending = omap_crtc->event != NULL;
  240. spin_unlock_irqrestore(&dev->event_lock, flags);
  241. return pending;
  242. }
  243. static void omap_crtc_wait_page_flip(struct drm_crtc *crtc)
  244. {
  245. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  246. if (wait_event_timeout(omap_crtc->flip_wait,
  247. !omap_crtc_page_flip_pending(crtc),
  248. msecs_to_jiffies(50)))
  249. return;
  250. dev_warn(crtc->dev->dev, "page flip timeout!\n");
  251. omap_crtc_complete_page_flip(crtc);
  252. }
  253. static void omap_crtc_error_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
  254. {
  255. struct omap_crtc *omap_crtc =
  256. container_of(irq, struct omap_crtc, error_irq);
  257. if (omap_crtc->ignore_digit_sync_lost) {
  258. irqstatus &= ~DISPC_IRQ_SYNC_LOST_DIGIT;
  259. if (!irqstatus)
  260. return;
  261. }
  262. DRM_ERROR_RATELIMITED("%s: errors: %08x\n", omap_crtc->name, irqstatus);
  263. }
  264. static void omap_crtc_vblank_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
  265. {
  266. struct omap_crtc *omap_crtc =
  267. container_of(irq, struct omap_crtc, vblank_irq);
  268. struct drm_device *dev = omap_crtc->base.dev;
  269. if (dispc_mgr_go_busy(omap_crtc->channel))
  270. return;
  271. DBG("%s: apply done", omap_crtc->name);
  272. __omap_irq_unregister(dev, &omap_crtc->vblank_irq);
  273. /* wakeup userspace */
  274. omap_crtc_complete_page_flip(&omap_crtc->base);
  275. complete(&omap_crtc->completion);
  276. }
  277. static int omap_crtc_flush(struct drm_crtc *crtc)
  278. {
  279. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  280. DBG("%s: GO", omap_crtc->name);
  281. WARN_ON(omap_crtc->vblank_irq.registered);
  282. if (dispc_mgr_is_enabled(omap_crtc->channel)) {
  283. dispc_mgr_go(omap_crtc->channel);
  284. omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);
  285. WARN_ON(!wait_for_completion_timeout(&omap_crtc->completion,
  286. msecs_to_jiffies(100)));
  287. reinit_completion(&omap_crtc->completion);
  288. }
  289. return 0;
  290. }
  291. static void omap_crtc_encoder_setup(struct drm_crtc *crtc, bool enable)
  292. {
  293. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  294. struct omap_drm_private *priv = crtc->dev->dev_private;
  295. struct drm_encoder *encoder = NULL;
  296. unsigned int i;
  297. DBG("%s: enable=%d", omap_crtc->name, enable);
  298. for (i = 0; i < priv->num_encoders; i++) {
  299. if (priv->encoders[i]->crtc == crtc) {
  300. encoder = priv->encoders[i];
  301. break;
  302. }
  303. }
  304. if (omap_crtc->current_encoder && encoder != omap_crtc->current_encoder)
  305. omap_encoder_set_enabled(omap_crtc->current_encoder, false);
  306. omap_crtc->current_encoder = encoder;
  307. if (encoder) {
  308. omap_encoder_set_enabled(encoder, false);
  309. if (enable) {
  310. omap_encoder_update(encoder, omap_crtc->mgr,
  311. &omap_crtc->timings);
  312. omap_encoder_set_enabled(encoder, true);
  313. }
  314. }
  315. }
  316. /* -----------------------------------------------------------------------------
  317. * CRTC Functions
  318. */
  319. static void omap_crtc_destroy(struct drm_crtc *crtc)
  320. {
  321. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  322. DBG("%s", omap_crtc->name);
  323. WARN_ON(omap_crtc->vblank_irq.registered);
  324. omap_irq_unregister(crtc->dev, &omap_crtc->error_irq);
  325. drm_crtc_cleanup(crtc);
  326. kfree(omap_crtc);
  327. }
  328. static bool omap_crtc_mode_fixup(struct drm_crtc *crtc,
  329. const struct drm_display_mode *mode,
  330. struct drm_display_mode *adjusted_mode)
  331. {
  332. return true;
  333. }
  334. static void omap_crtc_enable(struct drm_crtc *crtc)
  335. {
  336. struct omap_drm_private *priv = crtc->dev->dev_private;
  337. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  338. unsigned int i;
  339. DBG("%s", omap_crtc->name);
  340. dispc_runtime_get();
  341. /* Enable all planes associated with the CRTC. */
  342. for (i = 0; i < priv->num_planes; i++) {
  343. struct drm_plane *plane = priv->planes[i];
  344. if (plane->crtc == crtc)
  345. WARN_ON(omap_plane_setup(plane));
  346. }
  347. omap_crtc_encoder_setup(crtc, true);
  348. omap_crtc_flush(crtc);
  349. drm_crtc_vblank_on(crtc);
  350. dispc_runtime_put();
  351. }
  352. static void omap_crtc_disable(struct drm_crtc *crtc)
  353. {
  354. struct omap_drm_private *priv = crtc->dev->dev_private;
  355. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  356. unsigned int i;
  357. DBG("%s", omap_crtc->name);
  358. omap_crtc_wait_page_flip(crtc);
  359. dispc_runtime_get();
  360. drm_crtc_vblank_off(crtc);
  361. /* Disable all planes associated with the CRTC. */
  362. for (i = 0; i < priv->num_planes; i++) {
  363. struct drm_plane *plane = priv->planes[i];
  364. if (plane->crtc == crtc)
  365. WARN_ON(omap_plane_setup(plane));
  366. }
  367. omap_crtc_encoder_setup(crtc, false);
  368. omap_crtc_flush(crtc);
  369. dispc_runtime_put();
  370. }
  371. static void omap_crtc_mode_set_nofb(struct drm_crtc *crtc)
  372. {
  373. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  374. struct drm_display_mode *mode = &crtc->state->adjusted_mode;
  375. DBG("%s: set mode: %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x",
  376. omap_crtc->name, mode->base.id, mode->name,
  377. mode->vrefresh, mode->clock,
  378. mode->hdisplay, mode->hsync_start, mode->hsync_end, mode->htotal,
  379. mode->vdisplay, mode->vsync_start, mode->vsync_end, mode->vtotal,
  380. mode->type, mode->flags);
  381. copy_timings_drm_to_omap(&omap_crtc->timings, mode);
  382. }
  383. static void omap_crtc_atomic_begin(struct drm_crtc *crtc)
  384. {
  385. struct drm_pending_vblank_event *event = crtc->state->event;
  386. struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
  387. struct drm_device *dev = crtc->dev;
  388. unsigned long flags;
  389. dispc_runtime_get();
  390. if (event) {
  391. WARN_ON(omap_crtc->event);
  392. WARN_ON(drm_crtc_vblank_get(crtc) != 0);
  393. spin_lock_irqsave(&dev->event_lock, flags);
  394. omap_crtc->event = event;
  395. spin_unlock_irqrestore(&dev->event_lock, flags);
  396. }
  397. }
  398. static void omap_crtc_atomic_flush(struct drm_crtc *crtc)
  399. {
  400. omap_crtc_flush(crtc);
  401. dispc_runtime_put();
  402. crtc->invert_dimensions = !!(crtc->primary->state->rotation &
  403. (BIT(DRM_ROTATE_90) | BIT(DRM_ROTATE_270)));
  404. }
  405. static int omap_crtc_atomic_set_property(struct drm_crtc *crtc,
  406. struct drm_crtc_state *state,
  407. struct drm_property *property,
  408. uint64_t val)
  409. {
  410. struct drm_plane_state *plane_state;
  411. struct drm_plane *plane = crtc->primary;
  412. /*
  413. * Delegate property set to the primary plane. Get the plane state and
  414. * set the property directly.
  415. */
  416. plane_state = drm_atomic_get_plane_state(state->state, plane);
  417. if (!plane_state)
  418. return -EINVAL;
  419. return drm_atomic_plane_set_property(plane, plane_state, property, val);
  420. }
  421. static int omap_crtc_atomic_get_property(struct drm_crtc *crtc,
  422. const struct drm_crtc_state *state,
  423. struct drm_property *property,
  424. uint64_t *val)
  425. {
  426. /*
  427. * Delegate property get to the primary plane. The
  428. * drm_atomic_plane_get_property() function isn't exported, but can be
  429. * called through drm_object_property_get_value() as that will call
  430. * drm_atomic_get_property() for atomic drivers.
  431. */
  432. return drm_object_property_get_value(&crtc->primary->base, property,
  433. val);
  434. }
  435. static const struct drm_crtc_funcs omap_crtc_funcs = {
  436. .reset = drm_atomic_helper_crtc_reset,
  437. .set_config = drm_atomic_helper_set_config,
  438. .destroy = omap_crtc_destroy,
  439. .page_flip = drm_atomic_helper_page_flip,
  440. .set_property = drm_atomic_helper_crtc_set_property,
  441. .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
  442. .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
  443. .atomic_set_property = omap_crtc_atomic_set_property,
  444. .atomic_get_property = omap_crtc_atomic_get_property,
  445. };
  446. static const struct drm_crtc_helper_funcs omap_crtc_helper_funcs = {
  447. .mode_fixup = omap_crtc_mode_fixup,
  448. .mode_set_nofb = omap_crtc_mode_set_nofb,
  449. .disable = omap_crtc_disable,
  450. .enable = omap_crtc_enable,
  451. .atomic_begin = omap_crtc_atomic_begin,
  452. .atomic_flush = omap_crtc_atomic_flush,
  453. };
  454. /* -----------------------------------------------------------------------------
  455. * Init and Cleanup
  456. */
  457. static const char *channel_names[] = {
  458. [OMAP_DSS_CHANNEL_LCD] = "lcd",
  459. [OMAP_DSS_CHANNEL_DIGIT] = "tv",
  460. [OMAP_DSS_CHANNEL_LCD2] = "lcd2",
  461. [OMAP_DSS_CHANNEL_LCD3] = "lcd3",
  462. };
  463. void omap_crtc_pre_init(void)
  464. {
  465. dss_install_mgr_ops(&mgr_ops);
  466. }
  467. void omap_crtc_pre_uninit(void)
  468. {
  469. dss_uninstall_mgr_ops();
  470. }
  471. /* initialize crtc */
  472. struct drm_crtc *omap_crtc_init(struct drm_device *dev,
  473. struct drm_plane *plane, enum omap_channel channel, int id)
  474. {
  475. struct drm_crtc *crtc = NULL;
  476. struct omap_crtc *omap_crtc;
  477. int ret;
  478. DBG("%s", channel_names[channel]);
  479. omap_crtc = kzalloc(sizeof(*omap_crtc), GFP_KERNEL);
  480. if (!omap_crtc)
  481. return NULL;
  482. crtc = &omap_crtc->base;
  483. init_waitqueue_head(&omap_crtc->flip_wait);
  484. init_completion(&omap_crtc->completion);
  485. omap_crtc->channel = channel;
  486. omap_crtc->name = channel_names[channel];
  487. omap_crtc->vblank_irq.irqmask = pipe2vbl(crtc);
  488. omap_crtc->vblank_irq.irq = omap_crtc_vblank_irq;
  489. omap_crtc->error_irq.irqmask =
  490. dispc_mgr_get_sync_lost_irq(channel);
  491. omap_crtc->error_irq.irq = omap_crtc_error_irq;
  492. omap_irq_register(dev, &omap_crtc->error_irq);
  493. /* temporary: */
  494. omap_crtc->mgr = omap_dss_get_overlay_manager(channel);
  495. ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
  496. &omap_crtc_funcs);
  497. if (ret < 0) {
  498. kfree(omap_crtc);
  499. return NULL;
  500. }
  501. drm_crtc_helper_add(crtc, &omap_crtc_helper_funcs);
  502. omap_plane_install_properties(crtc->primary, &crtc->base);
  503. omap_crtcs[channel] = omap_crtc;
  504. return crtc;
  505. }