source: MondoRescue/branches/3.2/mindi-busybox/util-linux/fbset.c@ 3232

/* vi: set sw=4 ts=4: */
/*
 * Mini fbset implementation for busybox
 *
 * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 *
 * This is a from-scratch implementation of fbset; but the de facto fbset
 * implementation was a good reference. fbset (original) is released under
 * the GPL, and is (c) 1995-1999 by:
 *     Geert Uytterhoeven (Geert.Uytterhoeven@cs.kuleuven.ac.be)
 */

//usage:#define fbset_trivial_usage
//usage:       "[OPTIONS] [MODE]"
//usage:#define fbset_full_usage "\n\n"
//usage:       "Show and modify frame buffer settings"
//usage:
//usage:#define fbset_example_usage
//usage:       "$ fbset\n"
//usage:       "mode \"1024x768-76\"\n"
//usage:       "    # D: 78.653 MHz, H: 59.949 kHz, V: 75.694 Hz\n"
//usage:       "    geometry 1024 768 1024 768 16\n"
//usage:       "    timings 12714 128 32 16 4 128 4\n"
//usage:       "    accel false\n"
//usage:       "    rgba 5/11,6/5,5/0,0/0\n"
//usage:       "endmode\n"

#include "libbb.h"

#define DEFAULTFBDEV  FB_0
#define DEFAULTFBMODE "/etc/fb.modes"

/* Stuff stolen from the kernel's fb.h */
#define FB_ACTIVATE_ALL 64
enum {
    FBIOGET_VSCREENINFO = 0x4600,
    FBIOPUT_VSCREENINFO = 0x4601
};

struct fb_bitfield {
    uint32_t offset;                /* beginning of bitfield */
    uint32_t length;                /* length of bitfield */
    uint32_t msb_right;             /* !=0: Most significant bit is right */
};
struct fb_var_screeninfo {
    uint32_t xres;                  /* visible resolution */
    uint32_t yres;
    uint32_t xres_virtual;          /* virtual resolution */
    uint32_t yres_virtual;
    uint32_t xoffset;               /* offset from virtual to visible */
    uint32_t yoffset;               /* resolution */

    uint32_t bits_per_pixel;
    uint32_t grayscale;             /* !=0 Graylevels instead of colors */

    struct fb_bitfield red;         /* bitfield in fb mem if true color, */
    struct fb_bitfield green;       /* else only length is significant */
    struct fb_bitfield blue;
    struct fb_bitfield transp;      /* transparency */

    uint32_t nonstd;                /* !=0 Non standard pixel format */

    uint32_t activate;              /* see FB_ACTIVATE_x */

    uint32_t height;                /* height of picture in mm */
    uint32_t width;                 /* width of picture in mm */

    uint32_t accel_flags;           /* acceleration flags (hints) */

    /* Timing: All values in pixclocks, except pixclock (of course) */
    uint32_t pixclock;              /* pixel clock in ps (pico seconds) */
    uint32_t left_margin;           /* time from sync to picture */
    uint32_t right_margin;          /* time from picture to sync */
    uint32_t upper_margin;          /* time from sync to picture */
    uint32_t lower_margin;
    uint32_t hsync_len;             /* length of horizontal sync */
    uint32_t vsync_len;             /* length of vertical sync */
    uint32_t sync;                  /* see FB_SYNC_x */
    uint32_t vmode;                 /* see FB_VMODE_x */
    uint32_t reserved[6];           /* Reserved for future compatibility */
};

static void copy_if_gt0(uint32_t *src, uint32_t *dst, unsigned cnt)
{
    do {
        if ((int32_t) *src > 0)
            *dst = *src;
        src++;
        dst++;
    } while (--cnt);
}

static NOINLINE void copy_changed_values(
        struct fb_var_screeninfo *base,
        struct fb_var_screeninfo *set)
{
    //if ((int32_t) set->xres > 0) base->xres = set->xres;
    //if ((int32_t) set->yres > 0) base->yres = set->yres;
    //if ((int32_t) set->xres_virtual > 0)   base->xres_virtual = set->xres_virtual;
    //if ((int32_t) set->yres_virtual > 0)   base->yres_virtual = set->yres_virtual;
    copy_if_gt0(&set->xres, &base->xres, 4);

    if ((int32_t) set->bits_per_pixel > 0) base->bits_per_pixel = set->bits_per_pixel;
    //copy_if_gt0(&set->bits_per_pixel, &base->bits_per_pixel, 1);

    //if ((int32_t) set->pixclock > 0)       base->pixclock = set->pixclock;
    //if ((int32_t) set->left_margin > 0)    base->left_margin = set->left_margin;
    //if ((int32_t) set->right_margin > 0)   base->right_margin = set->right_margin;
    //if ((int32_t) set->upper_margin > 0)   base->upper_margin = set->upper_margin;
    //if ((int32_t) set->lower_margin > 0)   base->lower_margin = set->lower_margin;
    //if ((int32_t) set->hsync_len > 0) base->hsync_len = set->hsync_len;
    //if ((int32_t) set->vsync_len > 0) base->vsync_len = set->vsync_len;
    //if ((int32_t) set->sync > 0)  base->sync = set->sync;
    //if ((int32_t) set->vmode > 0) base->vmode = set->vmode;
    copy_if_gt0(&set->pixclock, &base->pixclock, 9);
}


enum {
    CMD_FB = 1,
    CMD_DB = 2,
    CMD_GEOMETRY = 3,
    CMD_TIMING = 4,
    CMD_ACCEL = 5,
    CMD_HSYNC = 6,
    CMD_VSYNC = 7,
    CMD_LACED = 8,
    CMD_DOUBLE = 9,
/*  CMD_XCOMPAT =     10, */
    CMD_ALL = 11,
    CMD_INFO = 12,
    CMD_SHOW = 13,
    CMD_CHANGE = 14,

#if ENABLE_FEATURE_FBSET_FANCY
    CMD_XRES = 100,
    CMD_YRES = 101,
    CMD_VXRES = 102,
    CMD_VYRES = 103,
    CMD_DEPTH = 104,
    CMD_MATCH = 105,
    CMD_PIXCLOCK = 106,
    CMD_LEFT = 107,
    CMD_RIGHT = 108,
    CMD_UPPER = 109,
    CMD_LOWER = 110,
    CMD_HSLEN = 111,
    CMD_VSLEN = 112,
    CMD_CSYNC = 113,
    CMD_GSYNC = 114,
    CMD_EXTSYNC = 115,
    CMD_BCAST = 116,
    CMD_RGBA = 117,
    CMD_STEP = 118,
    CMD_MOVE = 119,
#endif
};

static const struct cmdoptions_t {
    const char name[9];
    const unsigned char param_count;
    const unsigned char code;
} g_cmdoptions[] = {
    /*"12345678" + NUL */
    { "fb"      , 1, CMD_FB       },
    { "db"      , 1, CMD_DB       },
    { "a"       , 0, CMD_ALL      },
    { "i"       , 0, CMD_INFO     },
    { "g"       , 5, CMD_GEOMETRY },
    { "t"       , 7, CMD_TIMING   },
    { "accel"   , 1, CMD_ACCEL    },
    { "hsync"   , 1, CMD_HSYNC    },
    { "vsync"   , 1, CMD_VSYNC    },
    { "laced"   , 1, CMD_LACED    },
    { "double"  , 1, CMD_DOUBLE   },
    { "show"    , 0, CMD_SHOW     },
    { "s"       , 0, CMD_SHOW     },
#if ENABLE_FEATURE_FBSET_FANCY
    { "all"     , 0, CMD_ALL      },
    { "xres"    , 1, CMD_XRES     },
    { "yres"    , 1, CMD_YRES     },
    { "vxres"   , 1, CMD_VXRES    },
    { "vyres"   , 1, CMD_VYRES    },
    { "depth"   , 1, CMD_DEPTH    },
    { "match"   , 0, CMD_MATCH    },
    { "geometry", 5, CMD_GEOMETRY },
    { "pixclock", 1, CMD_PIXCLOCK },
    { "left"    , 1, CMD_LEFT     },
    { "right"   , 1, CMD_RIGHT    },
    { "upper"   , 1, CMD_UPPER    },
    { "lower"   , 1, CMD_LOWER    },
    { "hslen"   , 1, CMD_HSLEN    },
    { "vslen"   , 1, CMD_VSLEN    },
    { "timings" , 7, CMD_TIMING   },
    { "csync"   , 1, CMD_CSYNC    },
    { "gsync"   , 1, CMD_GSYNC    },
    { "extsync" , 1, CMD_EXTSYNC  },
    { "bcast"   , 1, CMD_BCAST    },
    { "rgba"    , 1, CMD_RGBA     },
    { "step"    , 1, CMD_STEP     },
    { "move"    , 1, CMD_MOVE     },
#endif
};

/* taken from linux/fb.h */
enum {
    FB_SYNC_HOR_HIGH_ACT = 1,       /* horizontal sync high active */
    FB_SYNC_VERT_HIGH_ACT = 2,      /* vertical sync high active */
#if ENABLE_FEATURE_FBSET_READMODE
    FB_VMODE_INTERLACED = 1,        /* interlaced */
    FB_VMODE_DOUBLE = 2,            /* double scan */
    FB_SYNC_EXT = 4,                /* external sync */
    FB_SYNC_COMP_HIGH_ACT = 8,      /* composite sync high active */
#endif
};

#if ENABLE_FEATURE_FBSET_READMODE
static void ss(uint32_t *x, uint32_t flag, char *buf, const char *what)
{
    if (strcmp(buf, what) == 0)
        *x &= ~flag;
    else
        *x |= flag;
}

/* Mode db file contains mode definitions like this:
 * mode "800x600-48-lace"
 *     # D: 36.00 MHz, H: 33.835 kHz, V: 96.39 Hz
 *     geometry 800 600 800 600 8
 *     timings 27778 56 80 79 11 128 12
 *     laced true
 *     hsync high
 *     vsync high
 * endmode
 */
static int read_mode_db(struct fb_var_screeninfo *base, const char *fn,
                    const char *mode)
{
    char *token[2], *p, *s;
    parser_t *parser = config_open(fn);

    while (config_read(parser, token, 2, 1, "# \t\r", PARSE_NORMAL)) {
        if (strcmp(token[0], "mode") != 0 || !token[1])
            continue;
        p = strstr(token[1], mode);
        if (!p)
            continue;
        s = p + strlen(mode);
        //bb_info_msg("CHECK[%s][%s][%d]", mode, p-1, *s);
        /* exact match? */
        if (((!*s || isspace(*s)) && '"' != s[-1]) /* end-of-token */
         || ('"' == *s && '"' == p[-1]) /* ends with " but starts with " too! */
        ) {
            //bb_info_msg("FOUND[%s][%s][%s][%d]", token[1], p, mode, isspace(*s));
            break;
        }
    }

    if (!token[0])
        return 0;

    while (config_read(parser, token, 2, 1, "# \t", PARSE_NORMAL)) {
        int i;

//bb_info_msg("???[%s][%s]", token[0], token[1]);
        if (strcmp(token[0], "endmode") == 0) {
//bb_info_msg("OK[%s]", mode);
            return 1;
        }
        p = token[1];
        i = index_in_strings(
            "geometry\0timings\0interlaced\0double\0vsync\0hsync\0csync\0extsync\0rgba\0",
            token[0]);
        switch (i) {
        case 0:
            if (sizeof(int) == sizeof(base->xres)) {
                sscanf(p, "%d %d %d %d %d",
                    &base->xres, &base->yres,
                    &base->xres_virtual, &base->yres_virtual,
                    &base->bits_per_pixel);
            } else {
                int base_xres, base_yres;
                int base_xres_virtual, base_yres_virtual;
                int base_bits_per_pixel;
                sscanf(p, "%d %d %d %d %d",
                    &base_xres, &base_yres,
                    &base_xres_virtual, &base_yres_virtual,
                    &base_bits_per_pixel);
                base->xres = base_xres;
                base->yres = base_yres;
                base->xres_virtual = base_xres_virtual;
                base->yres_virtual = base_yres_virtual;
                base->bits_per_pixel = base_bits_per_pixel;
            }
//bb_info_msg("GEO[%s]", p);
            break;
        case 1:
            if (sizeof(int) == sizeof(base->xres)) {
                sscanf(p, "%d %d %d %d %d %d %d",
                    &base->pixclock,
                    &base->left_margin, &base->right_margin,
                    &base->upper_margin, &base->lower_margin,
                    &base->hsync_len, &base->vsync_len);
            } else {
                int base_pixclock;
                int base_left_margin, base_right_margin;
                int base_upper_margin, base_lower_margin;
                int base_hsync_len, base_vsync_len;
                sscanf(p, "%d %d %d %d %d %d %d",
                    &base_pixclock,
                    &base_left_margin, &base_right_margin,
                    &base_upper_margin, &base_lower_margin,
                    &base_hsync_len, &base_vsync_len);
                base->pixclock = base_pixclock;
                base->left_margin = base_left_margin;
                base->right_margin = base_right_margin;
                base->upper_margin = base_upper_margin;
                base->lower_margin = base_lower_margin;
                base->hsync_len = base_hsync_len;
                base->vsync_len = base_vsync_len;
            }
//bb_info_msg("TIM[%s]", p);
            break;
        case 2:
        case 3: {
            static const uint32_t syncs[] = {FB_VMODE_INTERLACED, FB_VMODE_DOUBLE};
            ss(&base->vmode, syncs[i-2], p, "false");
//bb_info_msg("VMODE[%s]", p);
            break;
        }
        case 4:
        case 5:
        case 6: {
            static const uint32_t syncs[] = {FB_SYNC_VERT_HIGH_ACT, FB_SYNC_HOR_HIGH_ACT, FB_SYNC_COMP_HIGH_ACT};
            ss(&base->sync, syncs[i-4], p, "low");
//bb_info_msg("SYNC[%s]", p);
            break;
        }
        case 7:
            ss(&base->sync, FB_SYNC_EXT, p, "false");
//bb_info_msg("EXTSYNC[%s]", p);
            break;
        case 8: {
            int red_offset, red_length;
            int green_offset, green_length;
            int blue_offset, blue_length;
            int transp_offset, transp_length;

            sscanf(p, "%d/%d,%d/%d,%d/%d,%d/%d",
                &red_offset, &red_length,
                &green_offset, &green_length,
                &blue_offset, &blue_length,
                &transp_offset, &transp_length);
            base->red.offset = red_offset;
            base->red.length = red_length;
            base->red.msb_right = 0;
            base->green.offset = green_offset;
            base->green.length = green_length;
            base->green.msb_right = 0;
            base->blue.offset = blue_offset;
            base->blue.length = blue_length;
            base->blue.msb_right = 0;
            base->transp.offset = transp_offset;
            base->transp.length = transp_length;
            base->transp.msb_right = 0;
        }
        }
    }
    return 0;
}
#endif

static NOINLINE void showmode(struct fb_var_screeninfo *v)
{
    double drate = 0, hrate = 0, vrate = 0;

    if (v->pixclock) {
        drate = 1e12 / v->pixclock;
        hrate = drate / (v->left_margin + v->xres + v->right_margin + v->hsync_len);
        vrate = hrate / (v->upper_margin + v->yres + v->lower_margin + v->vsync_len);
    }
    printf("\nmode \"%ux%u-%u\"\n"
#if ENABLE_FEATURE_FBSET_FANCY
    "\t# D: %.3f MHz, H: %.3f kHz, V: %.3f Hz\n"
#endif
    "\tgeometry %u %u %u %u %u\n"
    "\ttimings %u %u %u %u %u %u %u\n"
    "\taccel %s\n"
    "\trgba %u/%u,%u/%u,%u/%u,%u/%u\n"
    "endmode\n\n",
        v->xres, v->yres, (int) (vrate + 0.5),
#if ENABLE_FEATURE_FBSET_FANCY
        drate / 1e6, hrate / 1e3, vrate,
#endif
        v->xres, v->yres, v->xres_virtual, v->yres_virtual, v->bits_per_pixel,
        v->pixclock, v->left_margin, v->right_margin, v->upper_margin, v->lower_margin,
            v->hsync_len, v->vsync_len,
        (v->accel_flags > 0 ? "true" : "false"),
        v->red.length, v->red.offset, v->green.length, v->green.offset,
            v->blue.length, v->blue.offset, v->transp.length, v->transp.offset);
}

int fbset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int fbset_main(int argc, char **argv)
{
    enum {
        OPT_CHANGE   = (1 << 0),
        OPT_SHOW     = (1 << 1),
        OPT_READMODE = (1 << 2),
        OPT_ALL      = (1 << 3),
    };
    struct fb_var_screeninfo var_old, var_set;
    int fh, i;
    unsigned options = 0;

    const char *fbdev = DEFAULTFBDEV;
    const char *modefile = DEFAULTFBMODE;
    char *thisarg;
    char *mode = mode; /* for compiler */

    memset(&var_set, 0xff, sizeof(var_set)); /* set all to -1 */

    /* parse cmd args.... why do they have to make things so difficult? */
    argv++;
    argc--;
    for (; argc > 0 && (thisarg = *argv) != NULL; argc--, argv++) {
        if (thisarg[0] != '-') {
            if (!ENABLE_FEATURE_FBSET_READMODE || argc != 1)
                bb_show_usage();
            mode = thisarg;
            options |= OPT_READMODE;
            goto contin;
        }
        for (i = 0; i < ARRAY_SIZE(g_cmdoptions); i++) {
            if (strcmp(thisarg + 1, g_cmdoptions[i].name) != 0)
                continue;
            if (argc <= g_cmdoptions[i].param_count)
                bb_show_usage();

            switch (g_cmdoptions[i].code) {
            case CMD_FB:
                fbdev = argv[1];
                break;
            case CMD_DB:
                modefile = argv[1];
                break;
            case CMD_ALL:
                options |= OPT_ALL;
                break;
            case CMD_SHOW:
                options |= OPT_SHOW;
                break;
            case CMD_GEOMETRY:
                var_set.xres = xatou32(argv[1]);
                var_set.yres = xatou32(argv[2]);
                var_set.xres_virtual = xatou32(argv[3]);
                var_set.yres_virtual = xatou32(argv[4]);
                var_set.bits_per_pixel = xatou32(argv[5]);
                break;
            case CMD_TIMING:
                var_set.pixclock = xatou32(argv[1]);
                var_set.left_margin = xatou32(argv[2]);
                var_set.right_margin = xatou32(argv[3]);
                var_set.upper_margin = xatou32(argv[4]);
                var_set.lower_margin = xatou32(argv[5]);
                var_set.hsync_len = xatou32(argv[6]);
                var_set.vsync_len = xatou32(argv[7]);
                break;
            case CMD_ACCEL:
                break;
            case CMD_HSYNC:
                var_set.sync |= FB_SYNC_HOR_HIGH_ACT;
                break;
            case CMD_VSYNC:
                var_set.sync |= FB_SYNC_VERT_HIGH_ACT;
                break;
#if ENABLE_FEATURE_FBSET_FANCY
            case CMD_XRES:
                var_set.xres = xatou32(argv[1]);
                break;
            case CMD_YRES:
                var_set.yres = xatou32(argv[1]);
                break;
            case CMD_DEPTH:
                var_set.bits_per_pixel = xatou32(argv[1]);
                break;
#endif
            }
            switch (g_cmdoptions[i].code) {
            case CMD_FB:
            case CMD_DB:
            case CMD_ALL:
            case CMD_SHOW:
                break;
            default:
                /* other commands imply changes */
                options |= OPT_CHANGE;
            }
            argc -= g_cmdoptions[i].param_count;
            argv += g_cmdoptions[i].param_count;
            goto contin;
        }
        bb_show_usage();
 contin: ;
    }

    fh = xopen(fbdev, O_RDONLY);
    xioctl(fh, FBIOGET_VSCREENINFO, &var_old);

    if (options & OPT_READMODE) {
#if ENABLE_FEATURE_FBSET_READMODE
        if (!read_mode_db(&var_old, modefile, mode)) {
            bb_error_msg_and_die("unknown video mode '%s'", mode);
        }
        options |= OPT_CHANGE;
#endif
    }

    if (options & OPT_CHANGE) {
        copy_changed_values(&var_old, &var_set);
        if (options & OPT_ALL)
            var_old.activate = FB_ACTIVATE_ALL;
        xioctl(fh, FBIOPUT_VSCREENINFO, &var_old);
    }

    if (options == 0 || (options & OPT_SHOW))
        showmode(&var_old);

    if (ENABLE_FEATURE_CLEAN_UP)
        close(fh);

    return EXIT_SUCCESS;
}