1/* vi: set sw=4 ts=4: */
2/*
3 * Mini fbset implementation for busybox
4 *
5 * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
8 *
9 * This is a from-scratch implementation of fbset; but the de facto fbset
10 * implementation was a good reference. fbset (original) is released under
11 * the GPL, and is (c) 1995-1999 by:
12 *     Geert Uytterhoeven (Geert.Uytterhoeven@cs.kuleuven.ac.be)
13 */
14
15#include "libbb.h"
16
17#define DEFAULTFBDEV  FB_0
18#define DEFAULTFBMODE "/etc/fb.modes"
19
20enum {
21	OPT_CHANGE   = (1 << 0),
22	OPT_INFO     = (1 << 1),
23	OPT_READMODE = (1 << 2),
24	OPT_ALL      = (1 << 9),
25
26	CMD_FB = 1,
27	CMD_DB = 2,
28	CMD_GEOMETRY = 3,
29	CMD_TIMING = 4,
30	CMD_ACCEL = 5,
31	CMD_HSYNC = 6,
32	CMD_VSYNC = 7,
33	CMD_LACED = 8,
34	CMD_DOUBLE = 9,
35/*	CMD_XCOMPAT =     10, */
36	CMD_ALL = 11,
37	CMD_INFO = 12,
38	CMD_CHANGE = 13,
39
40#if ENABLE_FEATURE_FBSET_FANCY
41	CMD_XRES = 100,
42	CMD_YRES = 101,
43	CMD_VXRES = 102,
44	CMD_VYRES = 103,
45	CMD_DEPTH = 104,
46	CMD_MATCH = 105,
47	CMD_PIXCLOCK = 106,
48	CMD_LEFT = 107,
49	CMD_RIGHT = 108,
50	CMD_UPPER = 109,
51	CMD_LOWER = 110,
52	CMD_HSLEN = 111,
53	CMD_VSLEN = 112,
54	CMD_CSYNC = 113,
55	CMD_GSYNC = 114,
56	CMD_EXTSYNC = 115,
57	CMD_BCAST = 116,
58	CMD_RGBA = 117,
59	CMD_STEP = 118,
60	CMD_MOVE = 119,
61#endif
62};
63
64static unsigned g_options;
65
66/* Stuff stolen from the kernel's fb.h */
67#define FB_ACTIVATE_ALL 64
68enum {
69	FBIOGET_VSCREENINFO = 0x4600,
70	FBIOPUT_VSCREENINFO = 0x4601
71};
72struct fb_bitfield {
73	uint32_t offset;                /* beginning of bitfield */
74	uint32_t length;		/* length of bitfield */
75	uint32_t msb_right;             /* !=0: Most significant bit is right */
76};
77struct fb_var_screeninfo {
78	uint32_t xres;                  /* visible resolution */
79	uint32_t yres;
80	uint32_t xres_virtual;          /* virtual resolution */
81	uint32_t yres_virtual;
82	uint32_t xoffset;               /* offset from virtual to visible */
83	uint32_t yoffset;               /* resolution */
84
85	uint32_t bits_per_pixel;
86	uint32_t grayscale;             /* !=0 Graylevels instead of colors */
87
88	struct fb_bitfield red;         /* bitfield in fb mem if true color, */
89	struct fb_bitfield green;       /* else only length is significant */
90	struct fb_bitfield blue;
91	struct fb_bitfield transp;      /* transparency */
92
93	uint32_t nonstd;                /* !=0 Non standard pixel format */
94
95	uint32_t activate;              /* see FB_ACTIVATE_x */
96
97	uint32_t height;                /* height of picture in mm */
98	uint32_t width;                 /* width of picture in mm */
99
100	uint32_t accel_flags;		/* acceleration flags (hints)	*/
101
102	/* Timing: All values in pixclocks, except pixclock (of course) */
103	uint32_t pixclock;              /* pixel clock in ps (pico seconds) */
104	uint32_t left_margin;           /* time from sync to picture */
105	uint32_t right_margin;          /* time from picture to sync */
106	uint32_t upper_margin;          /* time from sync to picture */
107	uint32_t lower_margin;
108	uint32_t hsync_len;             /* length of horizontal sync */
109	uint32_t vsync_len;             /* length of vertical sync */
110	uint32_t sync;                  /* see FB_SYNC_x */
111	uint32_t vmode;                 /* see FB_VMODE_x */
112	uint32_t reserved[6];           /* Reserved for future compatibility */
113};
114
115
116static const struct cmdoptions_t {
117	const char name[10];
118	const unsigned char param_count;
119	const unsigned char code;
120} g_cmdoptions[] = {
121	{ "-fb", 1, CMD_FB },
122	{ "-db", 1, CMD_DB },
123	{ "-a", 0, CMD_ALL },
124	{ "-i", 0, CMD_INFO },
125	{ "-g", 5, CMD_GEOMETRY },
126	{ "-t", 7, CMD_TIMING },
127	{ "-accel", 1, CMD_ACCEL },
128	{ "-hsync", 1, CMD_HSYNC },
129	{ "-vsync", 1, CMD_VSYNC },
130	{ "-laced", 1, CMD_LACED },
131	{ "-double", 1, CMD_DOUBLE },
132	{ "-n", 0, CMD_CHANGE },
133#if ENABLE_FEATURE_FBSET_FANCY
134	{ "-all", 0, CMD_ALL },
135	{ "-xres", 1, CMD_XRES },
136	{ "-yres", 1, CMD_YRES },
137	{ "-vxres", 1, CMD_VXRES },
138	{ "-vyres", 1, CMD_VYRES },
139	{ "-depth", 1, CMD_DEPTH },
140	{ "-match", 0, CMD_MATCH },
141	{ "-geometry", 5, CMD_GEOMETRY },
142	{ "-pixclock", 1, CMD_PIXCLOCK },
143	{ "-left", 1, CMD_LEFT },
144	{ "-right", 1, CMD_RIGHT },
145	{ "-upper", 1, CMD_UPPER },
146	{ "-lower", 1, CMD_LOWER },
147	{ "-hslen", 1, CMD_HSLEN },
148	{ "-vslen", 1, CMD_VSLEN },
149	{ "-timings", 7, CMD_TIMING },
150	{ "-csync", 1, CMD_CSYNC },
151	{ "-gsync", 1, CMD_GSYNC },
152	{ "-extsync", 1, CMD_EXTSYNC },
153	{ "-bcast", 1, CMD_BCAST },
154	{ "-rgba", 1, CMD_RGBA },
155	{ "-step", 1, CMD_STEP },
156	{ "-move", 1, CMD_MOVE },
157#endif
158	{ "", 0, 0 }
159};
160
161#if ENABLE_FEATURE_FBSET_READMODE
162/* taken from linux/fb.h */
163enum {
164	FB_VMODE_INTERLACED = 1,	/* interlaced	*/
165	FB_VMODE_DOUBLE = 2,	/* double scan */
166	FB_SYNC_HOR_HIGH_ACT = 1,	/* horizontal sync high active	*/
167	FB_SYNC_VERT_HIGH_ACT = 2,	/* vertical sync high active	*/
168	FB_SYNC_EXT = 4,	/* external sync		*/
169	FB_SYNC_COMP_HIGH_ACT = 8	/* composite sync high active   */
170};
171#endif
172
173static int readmode(struct fb_var_screeninfo *base, const char *fn,
174					const char *mode)
175{
176#if ENABLE_FEATURE_FBSET_READMODE
177	FILE *f;
178	char buf[256];
179	char *p = buf;
180
181	f = xfopen(fn, "r");
182	while (!feof(f)) {
183		fgets(buf, sizeof(buf), f);
184		if (!(p = strstr(buf, "mode ")) && !(p = strstr(buf, "mode\t")))
185			continue;
186		p += 5;
187		if (!(p = strstr(buf, mode)))
188			continue;
189		p += strlen(mode);
190		if (!isspace(*p) && (*p != 0) && (*p != '"')
191				&& (*p != '\r') && (*p != '\n'))
192			continue;	/* almost, but not quite */
193
194		while (!feof(f)) {
195			fgets(buf, sizeof(buf), f);
196			if ((p = strstr(buf, "geometry "))) {
197				p += 9;
198				sscanf(p, "%d %d %d %d %d",
199					&(base->xres), &(base->yres),
200					&(base->xres_virtual), &(base->yres_virtual),
201					&(base->bits_per_pixel));
202			} else if ((p = strstr(buf, "timings "))) {
203				p += 8;
204				sscanf(p, "%d %d %d %d %d %d %d",
205					&(base->pixclock),
206					&(base->left_margin), &(base->right_margin),
207					&(base->upper_margin), &(base->lower_margin),
208					&(base->hsync_len), &(base->vsync_len));
209			} else if ((p = strstr(buf, "laced "))) {
210				//p += 6;
211				if (strstr(buf, "false")) {
212					base->vmode &= ~FB_VMODE_INTERLACED;
213				} else {
214					base->vmode |= FB_VMODE_INTERLACED;
215				}
216			} else if ((p = strstr(buf, "double "))) {
217				//p += 7;
218				if (strstr(buf, "false")) {
219					base->vmode &= ~FB_VMODE_DOUBLE;
220				} else {
221					base->vmode |= FB_VMODE_DOUBLE;
222				}
223			} else if ((p = strstr(buf, "vsync "))) {
224				//p += 6;
225				if (strstr(buf, "low")) {
226					base->sync &= ~FB_SYNC_VERT_HIGH_ACT;
227				} else {
228					base->sync |= FB_SYNC_VERT_HIGH_ACT;
229				}
230			} else if ((p = strstr(buf, "hsync "))) {
231				//p += 6;
232				if (strstr(buf, "low")) {
233					base->sync &= ~FB_SYNC_HOR_HIGH_ACT;
234				} else {
235					base->sync |= FB_SYNC_HOR_HIGH_ACT;
236				}
237			} else if ((p = strstr(buf, "csync "))) {
238				//p += 6;
239				if (strstr(buf, "low")) {
240					base->sync &= ~FB_SYNC_COMP_HIGH_ACT;
241				} else {
242					base->sync |= FB_SYNC_COMP_HIGH_ACT;
243				}
244			} else if ((p = strstr(buf, "extsync "))) {
245				//p += 8;
246				if (strstr(buf, "false")) {
247					base->sync &= ~FB_SYNC_EXT;
248				} else {
249					base->sync |= FB_SYNC_EXT;
250				}
251			}
252
253			if (strstr(buf, "endmode"))
254				return 1;
255		}
256	}
257#else
258	bb_error_msg("mode reading not compiled in");
259#endif
260	return 0;
261}
262
263static inline void setmode(struct fb_var_screeninfo *base,
264					struct fb_var_screeninfo *set)
265{
266	if ((int) set->xres > 0)
267		base->xres = set->xres;
268	if ((int) set->yres > 0)
269		base->yres = set->yres;
270	if ((int) set->xres_virtual > 0)
271		base->xres_virtual = set->xres_virtual;
272	if ((int) set->yres_virtual > 0)
273		base->yres_virtual = set->yres_virtual;
274	if ((int) set->bits_per_pixel > 0)
275		base->bits_per_pixel = set->bits_per_pixel;
276}
277
278static inline void showmode(struct fb_var_screeninfo *v)
279{
280	double drate = 0, hrate = 0, vrate = 0;
281
282	if (v->pixclock) {
283		drate = 1e12 / v->pixclock;
284		hrate = drate / (v->left_margin + v->xres + v->right_margin + v->hsync_len);
285		vrate = hrate / (v->upper_margin + v->yres + v->lower_margin + v->vsync_len);
286	}
287	printf("\nmode \"%ux%u-%u\"\n"
288#if ENABLE_FEATURE_FBSET_FANCY
289	"\t# D: %.3f MHz, H: %.3f kHz, V: %.3f Hz\n"
290#endif
291	"\tgeometry %u %u %u %u %u\n"
292	"\ttimings %u %u %u %u %u %u %u\n"
293	"\taccel %s\n"
294	"\trgba %u/%u,%u/%u,%u/%u,%u/%u\n"
295	"endmode\n\n",
296		v->xres, v->yres, (int) (vrate + 0.5),
297#if ENABLE_FEATURE_FBSET_FANCY
298		drate / 1e6, hrate / 1e3, vrate,
299#endif
300		v->xres, v->yres, v->xres_virtual, v->yres_virtual, v->bits_per_pixel,
301		v->pixclock, v->left_margin, v->right_margin, v->upper_margin, v->lower_margin,
302			v->hsync_len, v->vsync_len,
303		(v->accel_flags > 0 ? "true" : "false"),
304		v->red.length, v->red.offset, v->green.length, v->green.offset,
305			v->blue.length, v->blue.offset, v->transp.length, v->transp.offset);
306}
307
308#ifdef STANDALONE
309int main(int argc, char **argv)
310#else
311int fbset_main(int argc, char **argv);
312int fbset_main(int argc, char **argv)
313#endif
314{
315	struct fb_var_screeninfo var, varset;
316	int fh, i;
317	const char *fbdev = DEFAULTFBDEV;
318	const char *modefile = DEFAULTFBMODE;
319	char *thisarg, *mode = NULL;
320
321	memset(&varset, 0xFF, sizeof(varset));
322
323	/* parse cmd args.... why do they have to make things so difficult? */
324	argv++;
325	argc--;
326	for (; argc > 0 && (thisarg = *argv); argc--, argv++) {
327		for (i = 0; g_cmdoptions[i].name[0]; i++) {
328			if (strcmp(thisarg, g_cmdoptions[i].name))
329				continue;
330			if (argc-1 < g_cmdoptions[i].param_count)
331				bb_show_usage();
332
333			switch (g_cmdoptions[i].code) {
334			case CMD_FB:
335				fbdev = argv[1];
336				break;
337			case CMD_DB:
338				modefile = argv[1];
339				break;
340			case CMD_GEOMETRY:
341				varset.xres = xatou32(argv[1]);
342				varset.yres = xatou32(argv[2]);
343				varset.xres_virtual = xatou32(argv[3]);
344				varset.yres_virtual = xatou32(argv[4]);
345				varset.bits_per_pixel = xatou32(argv[5]);
346				break;
347			case CMD_TIMING:
348				varset.pixclock = xatou32(argv[1]);
349				varset.left_margin = xatou32(argv[2]);
350				varset.right_margin = xatou32(argv[3]);
351				varset.upper_margin = xatou32(argv[4]);
352				varset.lower_margin = xatou32(argv[5]);
353				varset.hsync_len = xatou32(argv[6]);
354				varset.vsync_len = xatou32(argv[7]);
355				break;
356			case CMD_ALL:
357				g_options |= OPT_ALL;
358				break;
359			case CMD_CHANGE:
360				g_options |= OPT_CHANGE;
361				break;
362#if ENABLE_FEATURE_FBSET_FANCY
363			case CMD_XRES:
364				varset.xres = xatou32(argv[1]);
365				break;
366			case CMD_YRES:
367				varset.yres = xatou32(argv[1]);
368				break;
369			case CMD_DEPTH:
370				varset.bits_per_pixel = xatou32(argv[1]);
371				break;
372#endif
373			}
374			argc -= g_cmdoptions[i].param_count;
375			argv += g_cmdoptions[i].param_count;
376			break;
377		}
378		if (!g_cmdoptions[i].name[0]) {
379			if (argc != 1)
380				bb_show_usage();
381			mode = *argv;
382			g_options |= OPT_READMODE;
383		}
384	}
385
386	fh = xopen(fbdev, O_RDONLY);
387	xioctl(fh, FBIOGET_VSCREENINFO, &var);
388	if (g_options & OPT_READMODE) {
389		if (!readmode(&var, modefile, mode)) {
390			bb_error_msg_and_die("unknown video mode '%s'", mode);
391		}
392	}
393
394	setmode(&var, &varset);
395	if (g_options & OPT_CHANGE) {
396		if (g_options & OPT_ALL)
397			var.activate = FB_ACTIVATE_ALL;
398		xioctl(fh, FBIOPUT_VSCREENINFO, &var);
399	}
400	showmode(&var);
401	/* Don't close the file, as exiting will take care of that */
402	/* close(fh); */
403
404	return EXIT_SUCCESS;
405}
406