| /* | 
 |  * linux/drivers/video/omap2/dss/display.c | 
 |  * | 
 |  * Copyright (C) 2009 Nokia Corporation | 
 |  * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com> | 
 |  * | 
 |  * Some code and ideas taken from drivers/video/omap/ driver | 
 |  * by Imre Deak. | 
 |  * | 
 |  * 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/>. | 
 |  */ | 
 |  | 
 | #define DSS_SUBSYS_NAME "DISPLAY" | 
 |  | 
 | #include <linux/kernel.h> | 
 | #include <linux/module.h> | 
 | #include <linux/jiffies.h> | 
 | #include <linux/platform_device.h> | 
 |  | 
 | #include <video/omapdss.h> | 
 | #include "dss.h" | 
 |  | 
 | static ssize_t display_enabled_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	bool enabled = dssdev->state != OMAP_DSS_DISPLAY_DISABLED; | 
 |  | 
 | 	return snprintf(buf, PAGE_SIZE, "%d\n", enabled); | 
 | } | 
 |  | 
 | static ssize_t display_enabled_store(struct device *dev, | 
 | 		struct device_attribute *attr, | 
 | 		const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int r, enabled; | 
 |  | 
 | 	r = kstrtoint(buf, 0, &enabled); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	enabled = !!enabled; | 
 |  | 
 | 	if (enabled != (dssdev->state != OMAP_DSS_DISPLAY_DISABLED)) { | 
 | 		if (enabled) { | 
 | 			r = dssdev->driver->enable(dssdev); | 
 | 			if (r) | 
 | 				return r; | 
 | 		} else { | 
 | 			dssdev->driver->disable(dssdev); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static ssize_t display_upd_mode_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	enum omap_dss_update_mode mode = OMAP_DSS_UPDATE_AUTO; | 
 | 	if (dssdev->driver->get_update_mode) | 
 | 		mode = dssdev->driver->get_update_mode(dssdev); | 
 | 	return snprintf(buf, PAGE_SIZE, "%d\n", mode); | 
 | } | 
 |  | 
 | static ssize_t display_upd_mode_store(struct device *dev, | 
 | 		struct device_attribute *attr, | 
 | 		const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int val, r; | 
 | 	enum omap_dss_update_mode mode; | 
 |  | 
 | 	if (!dssdev->driver->set_update_mode) | 
 | 		return -EINVAL; | 
 |  | 
 | 	r = kstrtoint(buf, 0, &val); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	switch (val) { | 
 | 	case OMAP_DSS_UPDATE_DISABLED: | 
 | 	case OMAP_DSS_UPDATE_AUTO: | 
 | 	case OMAP_DSS_UPDATE_MANUAL: | 
 | 		mode = (enum omap_dss_update_mode)val; | 
 | 		break; | 
 | 	default: | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	r = dssdev->driver->set_update_mode(dssdev, mode); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static ssize_t display_tear_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	return snprintf(buf, PAGE_SIZE, "%d\n", | 
 | 			dssdev->driver->get_te ? | 
 | 			dssdev->driver->get_te(dssdev) : 0); | 
 | } | 
 |  | 
 | static ssize_t display_tear_store(struct device *dev, | 
 | 		struct device_attribute *attr, const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int te, r; | 
 |  | 
 | 	if (!dssdev->driver->enable_te || !dssdev->driver->get_te) | 
 | 		return -ENOENT; | 
 |  | 
 | 	r = kstrtoint(buf, 0, &te); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	te = !!te; | 
 |  | 
 | 	r = dssdev->driver->enable_te(dssdev, te); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static ssize_t display_timings_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	struct omap_video_timings t; | 
 |  | 
 | 	if (!dssdev->driver->get_timings) | 
 | 		return -ENOENT; | 
 |  | 
 | 	dssdev->driver->get_timings(dssdev, &t); | 
 |  | 
 | 	return snprintf(buf, PAGE_SIZE, "%u,%u/%u/%u/%u,%u/%u/%u/%u\n", | 
 | 			t.pixel_clock, | 
 | 			t.x_res, t.hfp, t.hbp, t.hsw, | 
 | 			t.y_res, t.vfp, t.vbp, t.vsw); | 
 | } | 
 |  | 
 | static ssize_t display_timings_store(struct device *dev, | 
 | 		struct device_attribute *attr, const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	struct omap_video_timings t; | 
 | 	int r, found; | 
 |  | 
 | 	if (!dssdev->driver->set_timings || !dssdev->driver->check_timings) | 
 | 		return -ENOENT; | 
 |  | 
 | 	found = 0; | 
 | #ifdef CONFIG_OMAP2_DSS_VENC | 
 | 	if (strncmp("pal", buf, 3) == 0) { | 
 | 		t = omap_dss_pal_timings; | 
 | 		found = 1; | 
 | 	} else if (strncmp("ntsc", buf, 4) == 0) { | 
 | 		t = omap_dss_ntsc_timings; | 
 | 		found = 1; | 
 | 	} | 
 | #endif | 
 | 	if (!found && sscanf(buf, "%u,%hu/%hu/%hu/%hu,%hu/%hu/%hu/%hu", | 
 | 				&t.pixel_clock, | 
 | 				&t.x_res, &t.hfp, &t.hbp, &t.hsw, | 
 | 				&t.y_res, &t.vfp, &t.vbp, &t.vsw) != 9) | 
 | 		return -EINVAL; | 
 |  | 
 | 	r = dssdev->driver->check_timings(dssdev, &t); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	dssdev->driver->set_timings(dssdev, &t); | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static ssize_t display_rotate_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int rotate; | 
 | 	if (!dssdev->driver->get_rotate) | 
 | 		return -ENOENT; | 
 | 	rotate = dssdev->driver->get_rotate(dssdev); | 
 | 	return snprintf(buf, PAGE_SIZE, "%u\n", rotate); | 
 | } | 
 |  | 
 | static ssize_t display_rotate_store(struct device *dev, | 
 | 		struct device_attribute *attr, const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int rot, r; | 
 |  | 
 | 	if (!dssdev->driver->set_rotate || !dssdev->driver->get_rotate) | 
 | 		return -ENOENT; | 
 |  | 
 | 	r = kstrtoint(buf, 0, &rot); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	r = dssdev->driver->set_rotate(dssdev, rot); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static ssize_t display_mirror_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int mirror; | 
 | 	if (!dssdev->driver->get_mirror) | 
 | 		return -ENOENT; | 
 | 	mirror = dssdev->driver->get_mirror(dssdev); | 
 | 	return snprintf(buf, PAGE_SIZE, "%u\n", mirror); | 
 | } | 
 |  | 
 | static ssize_t display_mirror_store(struct device *dev, | 
 | 		struct device_attribute *attr, const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	int mirror, r; | 
 |  | 
 | 	if (!dssdev->driver->set_mirror || !dssdev->driver->get_mirror) | 
 | 		return -ENOENT; | 
 |  | 
 | 	r = kstrtoint(buf, 0, &mirror); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	mirror = !!mirror; | 
 |  | 
 | 	r = dssdev->driver->set_mirror(dssdev, mirror); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static ssize_t display_wss_show(struct device *dev, | 
 | 		struct device_attribute *attr, char *buf) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	unsigned int wss; | 
 |  | 
 | 	if (!dssdev->driver->get_wss) | 
 | 		return -ENOENT; | 
 |  | 
 | 	wss = dssdev->driver->get_wss(dssdev); | 
 |  | 
 | 	return snprintf(buf, PAGE_SIZE, "0x%05x\n", wss); | 
 | } | 
 |  | 
 | static ssize_t display_wss_store(struct device *dev, | 
 | 		struct device_attribute *attr, const char *buf, size_t size) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 | 	u32 wss; | 
 | 	int r; | 
 |  | 
 | 	if (!dssdev->driver->get_wss || !dssdev->driver->set_wss) | 
 | 		return -ENOENT; | 
 |  | 
 | 	r = kstrtou32(buf, 0, &wss); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	if (wss > 0xfffff) | 
 | 		return -EINVAL; | 
 |  | 
 | 	r = dssdev->driver->set_wss(dssdev, wss); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	return size; | 
 | } | 
 |  | 
 | static DEVICE_ATTR(enabled, S_IRUGO|S_IWUSR, | 
 | 		display_enabled_show, display_enabled_store); | 
 | static DEVICE_ATTR(update_mode, S_IRUGO|S_IWUSR, | 
 | 		display_upd_mode_show, display_upd_mode_store); | 
 | static DEVICE_ATTR(tear_elim, S_IRUGO|S_IWUSR, | 
 | 		display_tear_show, display_tear_store); | 
 | static DEVICE_ATTR(timings, S_IRUGO|S_IWUSR, | 
 | 		display_timings_show, display_timings_store); | 
 | static DEVICE_ATTR(rotate, S_IRUGO|S_IWUSR, | 
 | 		display_rotate_show, display_rotate_store); | 
 | static DEVICE_ATTR(mirror, S_IRUGO|S_IWUSR, | 
 | 		display_mirror_show, display_mirror_store); | 
 | static DEVICE_ATTR(wss, S_IRUGO|S_IWUSR, | 
 | 		display_wss_show, display_wss_store); | 
 |  | 
 | static struct device_attribute *display_sysfs_attrs[] = { | 
 | 	&dev_attr_enabled, | 
 | 	&dev_attr_update_mode, | 
 | 	&dev_attr_tear_elim, | 
 | 	&dev_attr_timings, | 
 | 	&dev_attr_rotate, | 
 | 	&dev_attr_mirror, | 
 | 	&dev_attr_wss, | 
 | 	NULL | 
 | }; | 
 |  | 
 | void omapdss_default_get_resolution(struct omap_dss_device *dssdev, | 
 | 			u16 *xres, u16 *yres) | 
 | { | 
 | 	*xres = dssdev->panel.timings.x_res; | 
 | 	*yres = dssdev->panel.timings.y_res; | 
 | } | 
 | EXPORT_SYMBOL(omapdss_default_get_resolution); | 
 |  | 
 | void default_get_overlay_fifo_thresholds(enum omap_plane plane, | 
 | 		u32 fifo_size, enum omap_burst_size *burst_size, | 
 | 		u32 *fifo_low, u32 *fifo_high) | 
 | { | 
 | 	unsigned burst_size_bytes; | 
 |  | 
 | 	*burst_size = OMAP_DSS_BURST_16x32; | 
 | 	burst_size_bytes = 16 * 32 / 8; | 
 |  | 
 | 	*fifo_high = fifo_size - 1; | 
 | 	*fifo_low = fifo_size - burst_size_bytes; | 
 | } | 
 |  | 
 | int omapdss_default_get_recommended_bpp(struct omap_dss_device *dssdev) | 
 | { | 
 | 	switch (dssdev->type) { | 
 | 	case OMAP_DISPLAY_TYPE_DPI: | 
 | 		if (dssdev->phy.dpi.data_lines == 24) | 
 | 			return 24; | 
 | 		else | 
 | 			return 16; | 
 |  | 
 | 	case OMAP_DISPLAY_TYPE_DBI: | 
 | 	case OMAP_DISPLAY_TYPE_DSI: | 
 | 		if (dssdev->ctrl.pixel_size == 24) | 
 | 			return 24; | 
 | 		else | 
 | 			return 16; | 
 | 	case OMAP_DISPLAY_TYPE_VENC: | 
 | 	case OMAP_DISPLAY_TYPE_SDI: | 
 | 	case OMAP_DISPLAY_TYPE_HDMI: | 
 | 		return 24; | 
 | 	default: | 
 | 		BUG(); | 
 | 	} | 
 | } | 
 | EXPORT_SYMBOL(omapdss_default_get_recommended_bpp); | 
 |  | 
 | /* Checks if replication logic should be used. Only use for active matrix, | 
 |  * when overlay is in RGB12U or RGB16 mode, and LCD interface is | 
 |  * 18bpp or 24bpp */ | 
 | bool dss_use_replication(struct omap_dss_device *dssdev, | 
 | 		enum omap_color_mode mode) | 
 | { | 
 | 	int bpp; | 
 |  | 
 | 	if (mode != OMAP_DSS_COLOR_RGB12U && mode != OMAP_DSS_COLOR_RGB16) | 
 | 		return false; | 
 |  | 
 | 	if (dssdev->type == OMAP_DISPLAY_TYPE_DPI && | 
 | 			(dssdev->panel.config & OMAP_DSS_LCD_TFT) == 0) | 
 | 		return false; | 
 |  | 
 | 	switch (dssdev->type) { | 
 | 	case OMAP_DISPLAY_TYPE_DPI: | 
 | 		bpp = dssdev->phy.dpi.data_lines; | 
 | 		break; | 
 | 	case OMAP_DISPLAY_TYPE_HDMI: | 
 | 	case OMAP_DISPLAY_TYPE_VENC: | 
 | 	case OMAP_DISPLAY_TYPE_SDI: | 
 | 		bpp = 24; | 
 | 		break; | 
 | 	case OMAP_DISPLAY_TYPE_DBI: | 
 | 	case OMAP_DISPLAY_TYPE_DSI: | 
 | 		bpp = dssdev->ctrl.pixel_size; | 
 | 		break; | 
 | 	default: | 
 | 		BUG(); | 
 | 	} | 
 |  | 
 | 	return bpp > 16; | 
 | } | 
 |  | 
 | void dss_init_device(struct platform_device *pdev, | 
 | 		struct omap_dss_device *dssdev) | 
 | { | 
 | 	struct device_attribute *attr; | 
 | 	int i; | 
 | 	int r; | 
 |  | 
 | 	switch (dssdev->type) { | 
 | #ifdef CONFIG_OMAP2_DSS_DPI | 
 | 	case OMAP_DISPLAY_TYPE_DPI: | 
 | 		r = dpi_init_display(dssdev); | 
 | 		break; | 
 | #endif | 
 | #ifdef CONFIG_OMAP2_DSS_RFBI | 
 | 	case OMAP_DISPLAY_TYPE_DBI: | 
 | 		r = rfbi_init_display(dssdev); | 
 | 		break; | 
 | #endif | 
 | #ifdef CONFIG_OMAP2_DSS_VENC | 
 | 	case OMAP_DISPLAY_TYPE_VENC: | 
 | 		r = venc_init_display(dssdev); | 
 | 		break; | 
 | #endif | 
 | #ifdef CONFIG_OMAP2_DSS_SDI | 
 | 	case OMAP_DISPLAY_TYPE_SDI: | 
 | 		r = sdi_init_display(dssdev); | 
 | 		break; | 
 | #endif | 
 | #ifdef CONFIG_OMAP2_DSS_DSI | 
 | 	case OMAP_DISPLAY_TYPE_DSI: | 
 | 		r = dsi_init_display(dssdev); | 
 | 		break; | 
 | #endif | 
 | 	case OMAP_DISPLAY_TYPE_HDMI: | 
 | 		r = hdmi_init_display(dssdev); | 
 | 		break; | 
 | 	default: | 
 | 		DSSERR("Support for display '%s' not compiled in.\n", | 
 | 				dssdev->name); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	if (r) { | 
 | 		DSSERR("failed to init display %s\n", dssdev->name); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	/* create device sysfs files */ | 
 | 	i = 0; | 
 | 	while ((attr = display_sysfs_attrs[i++]) != NULL) { | 
 | 		r = device_create_file(&dssdev->dev, attr); | 
 | 		if (r) | 
 | 			DSSERR("failed to create sysfs file\n"); | 
 | 	} | 
 |  | 
 | 	/* create display? sysfs links */ | 
 | 	r = sysfs_create_link(&pdev->dev.kobj, &dssdev->dev.kobj, | 
 | 			dev_name(&dssdev->dev)); | 
 | 	if (r) | 
 | 		DSSERR("failed to create sysfs display link\n"); | 
 | } | 
 |  | 
 | void dss_uninit_device(struct platform_device *pdev, | 
 | 		struct omap_dss_device *dssdev) | 
 | { | 
 | 	struct device_attribute *attr; | 
 | 	int i = 0; | 
 |  | 
 | 	sysfs_remove_link(&pdev->dev.kobj, dev_name(&dssdev->dev)); | 
 |  | 
 | 	while ((attr = display_sysfs_attrs[i++]) != NULL) | 
 | 		device_remove_file(&dssdev->dev, attr); | 
 |  | 
 | 	if (dssdev->manager) | 
 | 		dssdev->manager->unset_device(dssdev->manager); | 
 | } | 
 |  | 
 | static int dss_suspend_device(struct device *dev, void *data) | 
 | { | 
 | 	int r; | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 |  | 
 | 	if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE) { | 
 | 		dssdev->activate_after_resume = false; | 
 | 		return 0; | 
 | 	} | 
 |  | 
 | 	if (!dssdev->driver->suspend) { | 
 | 		DSSERR("display '%s' doesn't implement suspend\n", | 
 | 				dssdev->name); | 
 | 		return -ENOSYS; | 
 | 	} | 
 |  | 
 | 	r = dssdev->driver->suspend(dssdev); | 
 | 	if (r) | 
 | 		return r; | 
 |  | 
 | 	dssdev->activate_after_resume = true; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | int dss_suspend_all_devices(void) | 
 | { | 
 | 	int r; | 
 | 	struct bus_type *bus = dss_get_bus(); | 
 |  | 
 | 	r = bus_for_each_dev(bus, NULL, NULL, dss_suspend_device); | 
 | 	if (r) { | 
 | 		/* resume all displays that were suspended */ | 
 | 		dss_resume_all_devices(); | 
 | 		return r; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int dss_resume_device(struct device *dev, void *data) | 
 | { | 
 | 	int r; | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 |  | 
 | 	if (dssdev->activate_after_resume && dssdev->driver->resume) { | 
 | 		r = dssdev->driver->resume(dssdev); | 
 | 		if (r) | 
 | 			return r; | 
 | 	} | 
 |  | 
 | 	dssdev->activate_after_resume = false; | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | int dss_resume_all_devices(void) | 
 | { | 
 | 	struct bus_type *bus = dss_get_bus(); | 
 |  | 
 | 	return bus_for_each_dev(bus, NULL, NULL, dss_resume_device); | 
 | } | 
 |  | 
 | static int dss_disable_device(struct device *dev, void *data) | 
 | { | 
 | 	struct omap_dss_device *dssdev = to_dss_device(dev); | 
 |  | 
 | 	if (dssdev->state != OMAP_DSS_DISPLAY_DISABLED) | 
 | 		dssdev->driver->disable(dssdev); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | void dss_disable_all_devices(void) | 
 | { | 
 | 	struct bus_type *bus = dss_get_bus(); | 
 | 	bus_for_each_dev(bus, NULL, NULL, dss_disable_device); | 
 | } | 
 |  | 
 |  | 
 | void omap_dss_get_device(struct omap_dss_device *dssdev) | 
 | { | 
 | 	get_device(&dssdev->dev); | 
 | } | 
 | EXPORT_SYMBOL(omap_dss_get_device); | 
 |  | 
 | void omap_dss_put_device(struct omap_dss_device *dssdev) | 
 | { | 
 | 	put_device(&dssdev->dev); | 
 | } | 
 | EXPORT_SYMBOL(omap_dss_put_device); | 
 |  | 
 | /* ref count of the found device is incremented. ref count | 
 |  * of from-device is decremented. */ | 
 | struct omap_dss_device *omap_dss_get_next_device(struct omap_dss_device *from) | 
 | { | 
 | 	struct device *dev; | 
 | 	struct device *dev_start = NULL; | 
 | 	struct omap_dss_device *dssdev = NULL; | 
 |  | 
 | 	int match(struct device *dev, void *data) | 
 | 	{ | 
 | 		return 1; | 
 | 	} | 
 |  | 
 | 	if (from) | 
 | 		dev_start = &from->dev; | 
 | 	dev = bus_find_device(dss_get_bus(), dev_start, NULL, match); | 
 | 	if (dev) | 
 | 		dssdev = to_dss_device(dev); | 
 | 	if (from) | 
 | 		put_device(&from->dev); | 
 |  | 
 | 	return dssdev; | 
 | } | 
 | EXPORT_SYMBOL(omap_dss_get_next_device); | 
 |  | 
 | struct omap_dss_device *omap_dss_find_device(void *data, | 
 | 		int (*match)(struct omap_dss_device *dssdev, void *data)) | 
 | { | 
 | 	struct omap_dss_device *dssdev = NULL; | 
 |  | 
 | 	while ((dssdev = omap_dss_get_next_device(dssdev)) != NULL) { | 
 | 		if (match(dssdev, data)) | 
 | 			return dssdev; | 
 | 	} | 
 |  | 
 | 	return NULL; | 
 | } | 
 | EXPORT_SYMBOL(omap_dss_find_device); | 
 |  | 
 | int omap_dss_start_device(struct omap_dss_device *dssdev) | 
 | { | 
 | 	if (!dssdev->driver) { | 
 | 		DSSDBG("no driver\n"); | 
 | 		return -ENODEV; | 
 | 	} | 
 |  | 
 | 	if (!try_module_get(dssdev->dev.driver->owner)) { | 
 | 		return -ENODEV; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 | EXPORT_SYMBOL(omap_dss_start_device); | 
 |  | 
 | void omap_dss_stop_device(struct omap_dss_device *dssdev) | 
 | { | 
 | 	module_put(dssdev->dev.driver->owner); | 
 | } | 
 | EXPORT_SYMBOL(omap_dss_stop_device); | 
 |  |