| /* | 
 |  * drivers/gpu/drm/omapdrm/omap_crtc.c | 
 |  * | 
 |  * Copyright (C) 2011 Texas Instruments | 
 |  * Author: Rob Clark <rob@ti.com> | 
 |  * | 
 |  * This program is free software; you can redistribute it and/or modify it | 
 |  * under the terms of the GNU General Public License version 2 as published by | 
 |  * the Free Software Foundation. | 
 |  * | 
 |  * This program is distributed in the hope that it will be useful, but WITHOUT | 
 |  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | 
 |  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for | 
 |  * more details. | 
 |  * | 
 |  * You should have received a copy of the GNU General Public License along with | 
 |  * this program.  If not, see <http://www.gnu.org/licenses/>. | 
 |  */ | 
 |  | 
 | #include <drm/drm_atomic.h> | 
 | #include <drm/drm_atomic_helper.h> | 
 | #include <drm/drm_crtc.h> | 
 | #include <drm/drm_crtc_helper.h> | 
 | #include <drm/drm_mode.h> | 
 | #include <drm/drm_plane_helper.h> | 
 |  | 
 | #include "omap_drv.h" | 
 |  | 
 | #define to_omap_crtc(x) container_of(x, struct omap_crtc, base) | 
 |  | 
 | struct omap_crtc { | 
 | 	struct drm_crtc base; | 
 |  | 
 | 	const char *name; | 
 | 	enum omap_channel channel; | 
 |  | 
 | 	struct videomode vm; | 
 |  | 
 | 	bool ignore_digit_sync_lost; | 
 |  | 
 | 	bool enabled; | 
 | 	bool pending; | 
 | 	wait_queue_head_t pending_wait; | 
 | 	struct drm_pending_vblank_event *event; | 
 | }; | 
 |  | 
 | /* ----------------------------------------------------------------------------- | 
 |  * Helper Functions | 
 |  */ | 
 |  | 
 | struct videomode *omap_crtc_timings(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	return &omap_crtc->vm; | 
 | } | 
 |  | 
 | enum omap_channel omap_crtc_channel(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	return omap_crtc->channel; | 
 | } | 
 |  | 
 | static bool omap_crtc_is_pending(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	unsigned long flags; | 
 | 	bool pending; | 
 |  | 
 | 	spin_lock_irqsave(&crtc->dev->event_lock, flags); | 
 | 	pending = omap_crtc->pending; | 
 | 	spin_unlock_irqrestore(&crtc->dev->event_lock, flags); | 
 |  | 
 | 	return pending; | 
 | } | 
 |  | 
 | int omap_crtc_wait_pending(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 |  | 
 | 	/* | 
 | 	 * Timeout is set to a "sufficiently" high value, which should cover | 
 | 	 * a single frame refresh even on slower displays. | 
 | 	 */ | 
 | 	return wait_event_timeout(omap_crtc->pending_wait, | 
 | 				  !omap_crtc_is_pending(crtc), | 
 | 				  msecs_to_jiffies(250)); | 
 | } | 
 |  | 
 | /* ----------------------------------------------------------------------------- | 
 |  * DSS Manager Functions | 
 |  */ | 
 |  | 
 | /* | 
 |  * Manager-ops, callbacks from output when they need to configure | 
 |  * the upstream part of the video pipe. | 
 |  * | 
 |  * Most of these we can ignore until we add support for command-mode | 
 |  * panels.. for video-mode the crtc-helpers already do an adequate | 
 |  * job of sequencing the setup of the video pipe in the proper order | 
 |  */ | 
 |  | 
 | /* ovl-mgr-id -> crtc */ | 
 | static struct omap_crtc *omap_crtcs[8]; | 
 | static struct omap_dss_device *omap_crtc_output[8]; | 
 |  | 
 | /* we can probably ignore these until we support command-mode panels: */ | 
 | static int omap_crtc_dss_connect(enum omap_channel channel, | 
 | 		struct omap_dss_device *dst) | 
 | { | 
 | 	if (omap_crtc_output[channel]) | 
 | 		return -EINVAL; | 
 |  | 
 | 	if ((dispc_mgr_get_supported_outputs(channel) & dst->id) == 0) | 
 | 		return -EINVAL; | 
 |  | 
 | 	omap_crtc_output[channel] = dst; | 
 | 	dst->dispc_channel_connected = true; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void omap_crtc_dss_disconnect(enum omap_channel channel, | 
 | 		struct omap_dss_device *dst) | 
 | { | 
 | 	omap_crtc_output[channel] = NULL; | 
 | 	dst->dispc_channel_connected = false; | 
 | } | 
 |  | 
 | static void omap_crtc_dss_start_update(enum omap_channel channel) | 
 | { | 
 | } | 
 |  | 
 | /* Called only from the encoder enable/disable and suspend/resume handlers. */ | 
 | static void omap_crtc_set_enabled(struct drm_crtc *crtc, bool enable) | 
 | { | 
 | 	struct drm_device *dev = crtc->dev; | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	enum omap_channel channel = omap_crtc->channel; | 
 | 	struct omap_irq_wait *wait; | 
 | 	u32 framedone_irq, vsync_irq; | 
 | 	int ret; | 
 |  | 
 | 	if (WARN_ON(omap_crtc->enabled == enable)) | 
 | 		return; | 
 |  | 
 | 	if (omap_crtc_output[channel]->output_type == OMAP_DISPLAY_TYPE_HDMI) { | 
 | 		dispc_mgr_enable(channel, enable); | 
 | 		omap_crtc->enabled = enable; | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	if (omap_crtc->channel == OMAP_DSS_CHANNEL_DIGIT) { | 
 | 		/* | 
 | 		 * Digit output produces some sync lost interrupts during the | 
 | 		 * first frame when enabling, so we need to ignore those. | 
 | 		 */ | 
 | 		omap_crtc->ignore_digit_sync_lost = true; | 
 | 	} | 
 |  | 
 | 	framedone_irq = dispc_mgr_get_framedone_irq(channel); | 
 | 	vsync_irq = dispc_mgr_get_vsync_irq(channel); | 
 |  | 
 | 	if (enable) { | 
 | 		wait = omap_irq_wait_init(dev, vsync_irq, 1); | 
 | 	} else { | 
 | 		/* | 
 | 		 * When we disable the digit output, we need to wait for | 
 | 		 * FRAMEDONE to know that DISPC has finished with the output. | 
 | 		 * | 
 | 		 * OMAP2/3 does not have FRAMEDONE irq for digit output, and in | 
 | 		 * that case we need to use vsync interrupt, and wait for both | 
 | 		 * even and odd frames. | 
 | 		 */ | 
 |  | 
 | 		if (framedone_irq) | 
 | 			wait = omap_irq_wait_init(dev, framedone_irq, 1); | 
 | 		else | 
 | 			wait = omap_irq_wait_init(dev, vsync_irq, 2); | 
 | 	} | 
 |  | 
 | 	dispc_mgr_enable(channel, enable); | 
 | 	omap_crtc->enabled = enable; | 
 |  | 
 | 	ret = omap_irq_wait(dev, wait, msecs_to_jiffies(100)); | 
 | 	if (ret) { | 
 | 		dev_err(dev->dev, "%s: timeout waiting for %s\n", | 
 | 				omap_crtc->name, enable ? "enable" : "disable"); | 
 | 	} | 
 |  | 
 | 	if (omap_crtc->channel == OMAP_DSS_CHANNEL_DIGIT) { | 
 | 		omap_crtc->ignore_digit_sync_lost = false; | 
 | 		/* make sure the irq handler sees the value above */ | 
 | 		mb(); | 
 | 	} | 
 | } | 
 |  | 
 |  | 
 | static int omap_crtc_dss_enable(enum omap_channel channel) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = omap_crtcs[channel]; | 
 | 	struct omap_overlay_manager_info info; | 
 |  | 
 | 	memset(&info, 0, sizeof(info)); | 
 | 	info.default_color = 0x00000000; | 
 | 	info.trans_key = 0x00000000; | 
 | 	info.trans_key_type = OMAP_DSS_COLOR_KEY_GFX_DST; | 
 | 	info.trans_enabled = false; | 
 |  | 
 | 	dispc_mgr_setup(omap_crtc->channel, &info); | 
 | 	dispc_mgr_set_timings(omap_crtc->channel, | 
 | 			&omap_crtc->vm); | 
 | 	omap_crtc_set_enabled(&omap_crtc->base, true); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void omap_crtc_dss_disable(enum omap_channel channel) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = omap_crtcs[channel]; | 
 |  | 
 | 	omap_crtc_set_enabled(&omap_crtc->base, false); | 
 | } | 
 |  | 
 | static void omap_crtc_dss_set_timings(enum omap_channel channel, | 
 | 		const struct videomode *vm) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = omap_crtcs[channel]; | 
 | 	DBG("%s", omap_crtc->name); | 
 | 	omap_crtc->vm = *vm; | 
 | } | 
 |  | 
 | static void omap_crtc_dss_set_lcd_config(enum omap_channel channel, | 
 | 		const struct dss_lcd_mgr_config *config) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = omap_crtcs[channel]; | 
 | 	DBG("%s", omap_crtc->name); | 
 | 	dispc_mgr_set_lcd_config(omap_crtc->channel, config); | 
 | } | 
 |  | 
 | static int omap_crtc_dss_register_framedone( | 
 | 		enum omap_channel channel, | 
 | 		void (*handler)(void *), void *data) | 
 | { | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void omap_crtc_dss_unregister_framedone( | 
 | 		enum omap_channel channel, | 
 | 		void (*handler)(void *), void *data) | 
 | { | 
 | } | 
 |  | 
 | static const struct dss_mgr_ops mgr_ops = { | 
 | 	.connect = omap_crtc_dss_connect, | 
 | 	.disconnect = omap_crtc_dss_disconnect, | 
 | 	.start_update = omap_crtc_dss_start_update, | 
 | 	.enable = omap_crtc_dss_enable, | 
 | 	.disable = omap_crtc_dss_disable, | 
 | 	.set_timings = omap_crtc_dss_set_timings, | 
 | 	.set_lcd_config = omap_crtc_dss_set_lcd_config, | 
 | 	.register_framedone_handler = omap_crtc_dss_register_framedone, | 
 | 	.unregister_framedone_handler = omap_crtc_dss_unregister_framedone, | 
 | }; | 
 |  | 
 | /* ----------------------------------------------------------------------------- | 
 |  * Setup, Flush and Page Flip | 
 |  */ | 
 |  | 
 | void omap_crtc_error_irq(struct drm_crtc *crtc, uint32_t irqstatus) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 |  | 
 | 	if (omap_crtc->ignore_digit_sync_lost) { | 
 | 		irqstatus &= ~DISPC_IRQ_SYNC_LOST_DIGIT; | 
 | 		if (!irqstatus) | 
 | 			return; | 
 | 	} | 
 |  | 
 | 	DRM_ERROR_RATELIMITED("%s: errors: %08x\n", omap_crtc->name, irqstatus); | 
 | } | 
 |  | 
 | void omap_crtc_vblank_irq(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	bool pending; | 
 |  | 
 | 	spin_lock(&crtc->dev->event_lock); | 
 | 	/* | 
 | 	 * If the dispc is busy we're racing the flush operation. Try again on | 
 | 	 * the next vblank interrupt. | 
 | 	 */ | 
 | 	if (dispc_mgr_go_busy(omap_crtc->channel)) { | 
 | 		spin_unlock(&crtc->dev->event_lock); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	/* Send the vblank event if one has been requested. */ | 
 | 	if (omap_crtc->event) { | 
 | 		drm_crtc_send_vblank_event(crtc, omap_crtc->event); | 
 | 		omap_crtc->event = NULL; | 
 | 	} | 
 |  | 
 | 	pending = omap_crtc->pending; | 
 | 	omap_crtc->pending = false; | 
 | 	spin_unlock(&crtc->dev->event_lock); | 
 |  | 
 | 	if (pending) | 
 | 		drm_crtc_vblank_put(crtc); | 
 |  | 
 | 	/* Wake up omap_atomic_complete. */ | 
 | 	wake_up(&omap_crtc->pending_wait); | 
 |  | 
 | 	DBG("%s: apply done", omap_crtc->name); | 
 | } | 
 |  | 
 | /* ----------------------------------------------------------------------------- | 
 |  * CRTC Functions | 
 |  */ | 
 |  | 
 | static void omap_crtc_destroy(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 |  | 
 | 	DBG("%s", omap_crtc->name); | 
 |  | 
 | 	drm_crtc_cleanup(crtc); | 
 |  | 
 | 	kfree(omap_crtc); | 
 | } | 
 |  | 
 | static void omap_crtc_enable(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	int ret; | 
 |  | 
 | 	DBG("%s", omap_crtc->name); | 
 |  | 
 | 	spin_lock_irq(&crtc->dev->event_lock); | 
 | 	drm_crtc_vblank_on(crtc); | 
 | 	ret = drm_crtc_vblank_get(crtc); | 
 | 	WARN_ON(ret != 0); | 
 |  | 
 | 	WARN_ON(omap_crtc->pending); | 
 | 	omap_crtc->pending = true; | 
 | 	spin_unlock_irq(&crtc->dev->event_lock); | 
 | } | 
 |  | 
 | static void omap_crtc_disable(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 |  | 
 | 	DBG("%s", omap_crtc->name); | 
 |  | 
 | 	drm_crtc_vblank_off(crtc); | 
 | } | 
 |  | 
 | static void omap_crtc_mode_set_nofb(struct drm_crtc *crtc) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	struct drm_display_mode *mode = &crtc->state->adjusted_mode; | 
 |  | 
 | 	DBG("%s: set mode: %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x", | 
 | 	    omap_crtc->name, mode->base.id, mode->name, | 
 | 	    mode->vrefresh, mode->clock, | 
 | 	    mode->hdisplay, mode->hsync_start, mode->hsync_end, mode->htotal, | 
 | 	    mode->vdisplay, mode->vsync_start, mode->vsync_end, mode->vtotal, | 
 | 	    mode->type, mode->flags); | 
 |  | 
 | 	drm_display_mode_to_videomode(mode, &omap_crtc->vm); | 
 | 	omap_crtc->vm.flags |= DISPLAY_FLAGS_DE_HIGH | | 
 | 			       DISPLAY_FLAGS_PIXDATA_POSEDGE | | 
 | 			       DISPLAY_FLAGS_SYNC_NEGEDGE; | 
 | } | 
 |  | 
 | static int omap_crtc_atomic_check(struct drm_crtc *crtc, | 
 | 				struct drm_crtc_state *state) | 
 | { | 
 | 	if (state->color_mgmt_changed && state->gamma_lut) { | 
 | 		uint length = state->gamma_lut->length / | 
 | 			sizeof(struct drm_color_lut); | 
 |  | 
 | 		if (length < 2) | 
 | 			return -EINVAL; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void omap_crtc_atomic_begin(struct drm_crtc *crtc, | 
 | 				   struct drm_crtc_state *old_crtc_state) | 
 | { | 
 | } | 
 |  | 
 | static void omap_crtc_atomic_flush(struct drm_crtc *crtc, | 
 | 				   struct drm_crtc_state *old_crtc_state) | 
 | { | 
 | 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc); | 
 | 	int ret; | 
 |  | 
 | 	if (crtc->state->color_mgmt_changed) { | 
 | 		struct drm_color_lut *lut = NULL; | 
 | 		uint length = 0; | 
 |  | 
 | 		if (crtc->state->gamma_lut) { | 
 | 			lut = (struct drm_color_lut *) | 
 | 				crtc->state->gamma_lut->data; | 
 | 			length = crtc->state->gamma_lut->length / | 
 | 				sizeof(*lut); | 
 | 		} | 
 | 		dispc_mgr_set_gamma(omap_crtc->channel, lut, length); | 
 | 	} | 
 |  | 
 | 	/* Only flush the CRTC if it is currently enabled. */ | 
 | 	if (!omap_crtc->enabled) | 
 | 		return; | 
 |  | 
 | 	DBG("%s: GO", omap_crtc->name); | 
 |  | 
 | 	ret = drm_crtc_vblank_get(crtc); | 
 | 	WARN_ON(ret != 0); | 
 |  | 
 | 	spin_lock_irq(&crtc->dev->event_lock); | 
 | 	dispc_mgr_go(omap_crtc->channel); | 
 |  | 
 | 	WARN_ON(omap_crtc->pending); | 
 | 	omap_crtc->pending = true; | 
 |  | 
 | 	if (crtc->state->event) | 
 | 		omap_crtc->event = crtc->state->event; | 
 | 	spin_unlock_irq(&crtc->dev->event_lock); | 
 | } | 
 |  | 
 | static bool omap_crtc_is_plane_prop(struct drm_crtc *crtc, | 
 | 	struct drm_property *property) | 
 | { | 
 | 	struct drm_device *dev = crtc->dev; | 
 | 	struct omap_drm_private *priv = dev->dev_private; | 
 |  | 
 | 	return property == priv->zorder_prop || | 
 | 		property == crtc->primary->rotation_property; | 
 | } | 
 |  | 
 | static int omap_crtc_atomic_set_property(struct drm_crtc *crtc, | 
 | 					 struct drm_crtc_state *state, | 
 | 					 struct drm_property *property, | 
 | 					 uint64_t val) | 
 | { | 
 | 	if (omap_crtc_is_plane_prop(crtc, property)) { | 
 | 		struct drm_plane_state *plane_state; | 
 | 		struct drm_plane *plane = crtc->primary; | 
 |  | 
 | 		/* | 
 | 		 * Delegate property set to the primary plane. Get the plane | 
 | 		 * state and set the property directly. | 
 | 		 */ | 
 |  | 
 | 		plane_state = drm_atomic_get_plane_state(state->state, plane); | 
 | 		if (IS_ERR(plane_state)) | 
 | 			return PTR_ERR(plane_state); | 
 |  | 
 | 		return drm_atomic_plane_set_property(plane, plane_state, | 
 | 				property, val); | 
 | 	} | 
 |  | 
 | 	return -EINVAL; | 
 | } | 
 |  | 
 | static int omap_crtc_atomic_get_property(struct drm_crtc *crtc, | 
 | 					 const struct drm_crtc_state *state, | 
 | 					 struct drm_property *property, | 
 | 					 uint64_t *val) | 
 | { | 
 | 	if (omap_crtc_is_plane_prop(crtc, property)) { | 
 | 		/* | 
 | 		 * Delegate property get to the primary plane. The | 
 | 		 * drm_atomic_plane_get_property() function isn't exported, but | 
 | 		 * can be called through drm_object_property_get_value() as that | 
 | 		 * will call drm_atomic_get_property() for atomic drivers. | 
 | 		 */ | 
 | 		return drm_object_property_get_value(&crtc->primary->base, | 
 | 				property, val); | 
 | 	} | 
 |  | 
 | 	return -EINVAL; | 
 | } | 
 |  | 
 | static const struct drm_crtc_funcs omap_crtc_funcs = { | 
 | 	.reset = drm_atomic_helper_crtc_reset, | 
 | 	.set_config = drm_atomic_helper_set_config, | 
 | 	.destroy = omap_crtc_destroy, | 
 | 	.page_flip = drm_atomic_helper_page_flip, | 
 | 	.gamma_set = drm_atomic_helper_legacy_gamma_set, | 
 | 	.set_property = drm_atomic_helper_crtc_set_property, | 
 | 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state, | 
 | 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state, | 
 | 	.atomic_set_property = omap_crtc_atomic_set_property, | 
 | 	.atomic_get_property = omap_crtc_atomic_get_property, | 
 | }; | 
 |  | 
 | static const struct drm_crtc_helper_funcs omap_crtc_helper_funcs = { | 
 | 	.mode_set_nofb = omap_crtc_mode_set_nofb, | 
 | 	.disable = omap_crtc_disable, | 
 | 	.enable = omap_crtc_enable, | 
 | 	.atomic_check = omap_crtc_atomic_check, | 
 | 	.atomic_begin = omap_crtc_atomic_begin, | 
 | 	.atomic_flush = omap_crtc_atomic_flush, | 
 | }; | 
 |  | 
 | /* ----------------------------------------------------------------------------- | 
 |  * Init and Cleanup | 
 |  */ | 
 |  | 
 | static const char *channel_names[] = { | 
 | 	[OMAP_DSS_CHANNEL_LCD] = "lcd", | 
 | 	[OMAP_DSS_CHANNEL_DIGIT] = "tv", | 
 | 	[OMAP_DSS_CHANNEL_LCD2] = "lcd2", | 
 | 	[OMAP_DSS_CHANNEL_LCD3] = "lcd3", | 
 | }; | 
 |  | 
 | void omap_crtc_pre_init(void) | 
 | { | 
 | 	dss_install_mgr_ops(&mgr_ops); | 
 | } | 
 |  | 
 | void omap_crtc_pre_uninit(void) | 
 | { | 
 | 	dss_uninstall_mgr_ops(); | 
 | } | 
 |  | 
 | /* initialize crtc */ | 
 | struct drm_crtc *omap_crtc_init(struct drm_device *dev, | 
 | 		struct drm_plane *plane, enum omap_channel channel, int id) | 
 | { | 
 | 	struct drm_crtc *crtc = NULL; | 
 | 	struct omap_crtc *omap_crtc; | 
 | 	int ret; | 
 |  | 
 | 	DBG("%s", channel_names[channel]); | 
 |  | 
 | 	omap_crtc = kzalloc(sizeof(*omap_crtc), GFP_KERNEL); | 
 | 	if (!omap_crtc) | 
 | 		return NULL; | 
 |  | 
 | 	crtc = &omap_crtc->base; | 
 |  | 
 | 	init_waitqueue_head(&omap_crtc->pending_wait); | 
 |  | 
 | 	omap_crtc->channel = channel; | 
 | 	omap_crtc->name = channel_names[channel]; | 
 |  | 
 | 	ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL, | 
 | 					&omap_crtc_funcs, NULL); | 
 | 	if (ret < 0) { | 
 | 		kfree(omap_crtc); | 
 | 		return NULL; | 
 | 	} | 
 |  | 
 | 	drm_crtc_helper_add(crtc, &omap_crtc_helper_funcs); | 
 |  | 
 | 	/* The dispc API adapts to what ever size, but the HW supports | 
 | 	 * 256 element gamma table for LCDs and 1024 element table for | 
 | 	 * OMAP_DSS_CHANNEL_DIGIT. X server assumes 256 element gamma | 
 | 	 * tables so lets use that. Size of HW gamma table can be | 
 | 	 * extracted with dispc_mgr_gamma_size(). If it returns 0 | 
 | 	 * gamma table is not supprted. | 
 | 	 */ | 
 | 	if (dispc_mgr_gamma_size(channel)) { | 
 | 		uint gamma_lut_size = 256; | 
 |  | 
 | 		drm_crtc_enable_color_mgmt(crtc, 0, false, gamma_lut_size); | 
 | 		drm_mode_crtc_set_gamma_size(crtc, gamma_lut_size); | 
 | 	} | 
 |  | 
 | 	omap_plane_install_properties(crtc->primary, &crtc->base); | 
 |  | 
 | 	omap_crtcs[channel] = omap_crtc; | 
 |  | 
 | 	return crtc; | 
 | } |