1 /* 2 * Copyright 2011 Florian Tobias Schandinat <FlorianSchandinat@gmx.de> 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License as published by the Free Software Foundation; 7 * either version 2, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even 11 * the implied warranty of MERCHANTABILITY or FITNESS FOR 12 * A PARTICULAR PURPOSE.See the GNU General Public License 13 * for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 */ 20 /* 21 * generic EDID driver 22 */ 23 24 #include <linux/slab.h> 25 #include <linux/fb.h> 26 #include "via_aux.h" 27 #include "../edid.h" 28 29 30 static const char *name = "EDID"; 31 32 33 static void query_edid(struct via_aux_drv *drv) 34 { 35 struct fb_monspecs *spec = drv->data; 36 unsigned char edid[EDID_LENGTH]; 37 bool valid = false; 38 39 if (spec) { 40 fb_destroy_modedb(spec->modedb); 41 } else { 42 spec = kmalloc(sizeof(*spec), GFP_KERNEL); 43 if (!spec) 44 return; 45 } 46 47 spec->version = spec->revision = 0; 48 if (via_aux_read(drv, 0x00, edid, EDID_LENGTH)) { 49 fb_edid_to_monspecs(edid, spec); 50 valid = spec->version || spec->revision; 51 } 52 53 if (!valid) { 54 kfree(spec); 55 spec = NULL; 56 } else 57 printk(KERN_DEBUG "EDID: %s %s\n", spec->manufacturer, spec->monitor); 58 59 drv->data = spec; 60 } 61 62 static const struct fb_videomode *get_preferred_mode(struct via_aux_drv *drv) 63 { 64 struct fb_monspecs *spec = drv->data; 65 int i; 66 67 if (!spec || !spec->modedb || !(spec->misc & FB_MISC_1ST_DETAIL)) 68 return NULL; 69 70 for (i = 0; i < spec->modedb_len; i++) { 71 if (spec->modedb[i].flag & FB_MODE_IS_FIRST && 72 spec->modedb[i].flag & FB_MODE_IS_DETAILED) 73 return &spec->modedb[i]; 74 } 75 76 return NULL; 77 } 78 79 static void cleanup(struct via_aux_drv *drv) 80 { 81 struct fb_monspecs *spec = drv->data; 82 83 if (spec) 84 fb_destroy_modedb(spec->modedb); 85 } 86 87 void via_aux_edid_probe(struct via_aux_bus *bus) 88 { 89 struct via_aux_drv drv = { 90 .bus = bus, 91 .addr = 0x50, 92 .name = name, 93 .cleanup = cleanup, 94 .get_preferred_mode = get_preferred_mode}; 95 96 query_edid(&drv); 97 98 /* as EDID devices can be connected/disconnected just add the driver */ 99 via_aux_add(&drv); 100 } 101