drivers/video/fbdev/mmp/core.c

   1 /*
   2  * linux/drivers/video/mmp/common.c
   3  * This driver is a common framework for Marvell Display Controller
   4  *
   5  * Copyright (C) 2012 Marvell Technology Group Ltd.
   6  * Authors: Zhou Zhu <zzhu3@marvell.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2 of the License, or (at your
  11  * option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  16  * more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along with
  19  * this program.  If not, see <http://www.gnu.org/licenses/>.
  20  *
  21  */
  22
  23 #include <linux/slab.h>
  24 #include <linux/dma-mapping.h>
  25 #include <linux/export.h>
  26 #include <video/mmp_disp.h>
  27
  28 static struct mmp_overlay *path_get_overlay(struct mmp_path *path,
  29                 int overlay_id)
  30 {
  31         if (path && overlay_id < path->overlay_num)
  32                 return &path->overlays[overlay_id];
  33         return NULL;
  34 }
  35
  36 static int path_check_status(struct mmp_path *path)
  37 {
  38         int i;
  39         for (i = 0; i < path->overlay_num; i++)
  40                 if (path->overlays[i].status)
  41                         return 1;
  42
  43         return 0;
  44 }
  45
  46 /*
  47  * Get modelist write pointer of modelist.
  48  * It also returns modelist number
  49  * this function fetches modelist from phy/panel:
  50  *   for HDMI/parallel or dsi to hdmi cases, get from phy
  51  *   or get from panel
  52  */
  53 static int path_get_modelist(struct mmp_path *path,
  54                 struct mmp_mode **modelist)
  55 {
  56         BUG_ON(!path || !modelist);
  57
  58         if (path->panel && path->panel->get_modelist)
  59                 return path->panel->get_modelist(path->panel, modelist);
  60
  61         return 0;
  62 }
  63
  64 /*
  65  * panel list is used to pair panel/path when path/panel registered
  66  * path list is used for both buffer driver and platdriver
  67  * plat driver do path register/unregister
  68  * panel driver do panel register/unregister
  69  * buffer driver get registered path
  70  */
  71 static LIST_HEAD(panel_list);
  72 static LIST_HEAD(path_list);
  73 static DEFINE_MUTEX(disp_lock);
  74
  75 /*
  76  * mmp_register_panel - register panel to panel_list and connect to path
  77  * @p: panel to be registered
  78  *
  79  * this function provides interface for panel drivers to register panel
  80  * to panel_list and connect to path which matchs panel->plat_path_name.
  81  * no error returns when no matching path is found as path register after
  82  * panel register is permitted.
  83  */
  84 void mmp_register_panel(struct mmp_panel *panel)
  85 {
  86         struct mmp_path *path;
  87
  88         mutex_lock(&disp_lock);
  89
  90         /* add */
  91         list_add_tail(&panel->node, &panel_list);
  92
  93         /* try to register to path */
  94         list_for_each_entry(path, &path_list, node) {
  95                 if (!strcmp(panel->plat_path_name, path->name)) {
  96                         dev_info(panel->dev, "connect to path %s\n",
  97                                 path->name);
  98                         path->panel = panel;
  99                         break;
 100                 }
 101         }
 102
 103         mutex_unlock(&disp_lock);
 104 }
 105 EXPORT_SYMBOL_GPL(mmp_register_panel);
 106
 107 /*
 108  * mmp_unregister_panel - unregister panel from panel_list and disconnect
 109  * @p: panel to be unregistered
 110  *
 111  * this function provides interface for panel drivers to unregister panel
 112  * from panel_list and disconnect from path.
 113  */
 114 void mmp_unregister_panel(struct mmp_panel *panel)
 115 {
 116         struct mmp_path *path;
 117
 118         mutex_lock(&disp_lock);
 119         list_del(&panel->node);
 120
 121         list_for_each_entry(path, &path_list, node) {
 122                 if (path->panel && path->panel == panel) {
 123                         dev_info(panel->dev, "disconnect from path %s\n",
 124                                 path->name);
 125                         path->panel = NULL;
 126                         break;
 127                 }
 128         }
 129         mutex_unlock(&disp_lock);
 130 }
 131 EXPORT_SYMBOL_GPL(mmp_unregister_panel);
 132
 133 /*
 134  * mmp_get_path - get path by name
 135  * @p: path name
 136  *
 137  * this function checks path name in path_list and return matching path
 138  * return NULL if no matching path
 139  */
 140 struct mmp_path *mmp_get_path(const char *name)
 141 {
 142         struct mmp_path *path;
 143         int found = 0;
 144
 145         mutex_lock(&disp_lock);
 146         list_for_each_entry(path, &path_list, node) {
 147                 if (!strcmp(name, path->name)) {
 148                         found = 1;
 149                         break;
 150                 }
 151         }
 152         mutex_unlock(&disp_lock);
 153
 154         return found ? path : NULL;
 155 }
 156 EXPORT_SYMBOL_GPL(mmp_get_path);
 157
 158 /*
 159  * mmp_register_path - init and register path by path_info
 160  * @p: path info provided by display controller
 161  *
 162  * this function init by path info and register path to path_list
 163  * this function also try to connect path with panel by name
 164  */
 165 struct mmp_path *mmp_register_path(struct mmp_path_info *info)
 166 {
 167         int i;
 168         size_t size;
 169         struct mmp_path *path = NULL;
 170         struct mmp_panel *panel;
 171
 172         size = sizeof(struct mmp_path)
 173                 + sizeof(struct mmp_overlay) * info->overlay_num;
 174         path = kzalloc(size, GFP_KERNEL);
 175         if (!path)
 176                 return NULL;
 177
 178         /* path set */
 179         mutex_init(&path->access_ok);
 180         path->dev = info->dev;
 181         path->id = info->id;
 182         path->name = info->name;
 183         path->output_type = info->output_type;
 184         path->overlay_num = info->overlay_num;
 185         path->plat_data = info->plat_data;
 186         path->ops.set_mode = info->set_mode;
 187
 188         mutex_lock(&disp_lock);
 189         /* get panel */
 190         list_for_each_entry(panel, &panel_list, node) {
 191                 if (!strcmp(info->name, panel->plat_path_name)) {
 192                         dev_info(path->dev, "get panel %s\n", panel->name);
 193                         path->panel = panel;
 194                         break;
 195                 }
 196         }
 197
 198         dev_info(path->dev, "register %s, overlay_num %d\n",
 199                         path->name, path->overlay_num);
 200
 201         /* default op set: if already set by driver, never cover it */
 202         if (!path->ops.check_status)
 203                 path->ops.check_status = path_check_status;
 204         if (!path->ops.get_overlay)
 205                 path->ops.get_overlay = path_get_overlay;
 206         if (!path->ops.get_modelist)
 207                 path->ops.get_modelist = path_get_modelist;
 208
 209         /* step3: init overlays */
 210         for (i = 0; i < path->overlay_num; i++) {
 211                 path->overlays[i].path = path;
 212                 path->overlays[i].id = i;
 213                 mutex_init(&path->overlays[i].access_ok);
 214                 path->overlays[i].ops = info->overlay_ops;
 215         }
 216
 217         /* add to pathlist */
 218         list_add_tail(&path->node, &path_list);
 219
 220         mutex_unlock(&disp_lock);
 221         return path;
 222 }
 223 EXPORT_SYMBOL_GPL(mmp_register_path);
 224
 225 /*
 226  * mmp_unregister_path - unregister and destroy path
 227  * @p: path to be destroyed.
 228  *
 229  * this function registers path and destroys it.
 230  */
 231 void mmp_unregister_path(struct mmp_path *path)
 232 {
 233         int i;
 234
 235         if (!path)
 236                 return;
 237
 238         mutex_lock(&disp_lock);
 239         /* del from pathlist */
 240         list_del(&path->node);
 241
 242         /* deinit overlays */
 243         for (i = 0; i < path->overlay_num; i++)
 244                 mutex_destroy(&path->overlays[i].access_ok);
 245
 246         mutex_destroy(&path->access_ok);
 247
 248         kfree(path);
 249         mutex_unlock(&disp_lock);
 250 }
 251 EXPORT_SYMBOL_GPL(mmp_unregister_path);