path: root/drivers/gpu/drm/drm_fb_helper.c

/*
 * Copyright (c) 2006-2009 Red Hat Inc.
 * Copyright (c) 2006-2008 Intel Corporation
 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
 *
 * DRM framebuffer helper functions
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 *
 * Authors:
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */
#include <linux/sysrq.h>
#include <linux/fb.h>
#include "drmP.h"
#include "drm_crtc.h"
#include "drm_fb_helper.h"
#include "drm_crtc_helper.h"

MODULE_AUTHOR("David Airlie, Jesse Barnes");
MODULE_DESCRIPTION("DRM KMS helper");
MODULE_LICENSE("GPL and additional rights");

static LIST_HEAD(kernel_fb_helper_list);

int drm_fb_helper_add_connector(struct drm_connector *connector)
{
	connector->fb_helper_private = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
	if (!connector->fb_helper_private)
		return -ENOMEM;

	return 0;
}
EXPORT_SYMBOL(drm_fb_helper_add_connector);

static int my_atoi(const char *name)
{
	int val = 0;

	for (;; name++) {
		switch (*name) {
		case '0' ... '9':
			val = 10*val+(*name-'0');
			break;
		default:
			return val;
		}
	}
}

/**
 * drm_fb_helper_connector_parse_command_line - parse command line for connector
 * @connector - connector to parse line for
 * @mode_option - per connector mode option
 *
 * This parses the connector specific then generic command lines for
 * modes and options to configure the connector.
 *
 * This uses the same parameters as the fb modedb.c, except for extra
 *	<xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
 *
 * enable/enable Digital/disable bit at the end
 */
static bool drm_fb_helper_connector_parse_command_line(struct drm_connector *connector,
						       const char *mode_option)
{
	const char *name;
	unsigned int namelen;
	int res_specified = 0, bpp_specified = 0, refresh_specified = 0;
	unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0;
	int yres_specified = 0, cvt = 0, rb = 0, interlace = 0, margins = 0;
	int i;
	enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
	struct drm_fb_helper_connector *fb_help_conn = connector->fb_helper_private;
	struct drm_fb_helper_cmdline_mode *cmdline_mode;

	if (!fb_help_conn)
		return false;

	cmdline_mode = &fb_help_conn->cmdline_mode;
	if (!mode_option)
		mode_option = fb_mode_option;

	if (!mode_option) {
		cmdline_mode->specified = false;
		return false;
	}

	name = mode_option;
	namelen = strlen(name);
	for (i = namelen-1; i >= 0; i--) {
		switch (name[i]) {
		case '@':
			namelen = i;
			if (!refresh_specified && !bpp_specified &&
			    !yres_specified) {
				refresh = my_atoi(&name[i+1]);
				refresh_specified = 1;
				if (cvt || rb)
					cvt = 0;
			} else
				goto done;
			break;
		case '-':
			namelen = i;
			if (!bpp_specified && !yres_specified) {
				bpp = my_atoi(&name[i+1]);
				bpp_specified = 1;
				if (cvt || rb)
					cvt = 0;
			} else
				goto done;
			break;
		case 'x':
			if (!yres_specified) {
				yres = my_atoi(&name[i+1]);
				yres_specified = 1;
			} else
				goto done;
		case '0' ... '9':
			break;
		case 'M':
			if (!yres_specified)
				cvt = 1;
			break;
		case 'R':
			if (!cvt)
				rb = 1;
			break;
		case