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      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  * Copyright (c) 2010 - 2013, The Linux Foundation. All rights reserved.
      4  *
      5  * Not a Contribution, Apache license notifications and license are retained
      6  * for attribution purposes only.
      7  *
      8  * Licensed under the Apache License, Version 2.0 (the "License");
      9  * you may not use this file except in compliance with the License.
     10  * You may obtain a copy of the License at
     11  *
     12  *      http://www.apache.org/licenses/LICENSE-2.0
     13  *
     14  * Unless required by applicable law or agreed to in writing, software
     15  * distributed under the License is distributed on an "AS IS" BASIS,
     16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     17  * See the License for the specific language governing permissions and
     18  * limitations under the License.
     19  */
     20 
     21 #include <cutils/log.h>
     22 
     23 #include <linux/msm_mdp.h>
     24 #include <linux/fb.h>
     25 
     26 #include <stdint.h>
     27 #include <string.h>
     28 #include <unistd.h>
     29 #include <errno.h>
     30 #include <fcntl.h>
     31 
     32 #include <sys/ioctl.h>
     33 #include <sys/types.h>
     34 #include <sys/mman.h>
     35 
     36 #include <copybit.h>
     37 
     38 #include "gralloc_priv.h"
     39 #include "software_converter.h"
     40 
     41 #define DEBUG_MDP_ERRORS 1
     42 
     43 /******************************************************************************/
     44 
     45 #define MAX_SCALE_FACTOR    (4)
     46 #define MAX_DIMENSION       (4096)
     47 
     48 /******************************************************************************/
     49 struct blitReq{
     50     struct  mdp_buf_sync sync;
     51     uint32_t count;
     52     struct mdp_blit_req req[10];
     53 };
     54 
     55 /** State information for each device instance */
     56 struct copybit_context_t {
     57     struct copybit_device_t device;
     58     int     mFD;
     59     uint8_t mAlpha;
     60     int     mFlags;
     61     bool    mBlitToFB;
     62     int     acqFence[MDP_MAX_FENCE_FD];
     63     int     relFence;
     64     struct  mdp_buf_sync sync;
     65     struct  blitReq list;
     66 };
     67 
     68 /**
     69  * Common hardware methods
     70  */
     71 
     72 static int open_copybit(const struct hw_module_t* module, const char* name,
     73                         struct hw_device_t** device);
     74 
     75 static struct hw_module_methods_t copybit_module_methods = {
     76 open:  open_copybit
     77 };
     78 
     79 /*
     80  * The COPYBIT Module
     81  */
     82 struct copybit_module_t HAL_MODULE_INFO_SYM = {
     83 common: {
     84 tag: HARDWARE_MODULE_TAG,
     85      version_major: 1,
     86      version_minor: 0,
     87      id: COPYBIT_HARDWARE_MODULE_ID,
     88      name: "QCT MSM7K COPYBIT Module",
     89      author: "Google, Inc.",
     90      methods: &copybit_module_methods
     91         }
     92 };
     93 
     94 /******************************************************************************/
     95 
     96 /** min of int a, b */
     97 static inline int min(int a, int b) {
     98     return (a<b) ? a : b;
     99 }
    100 
    101 /** max of int a, b */
    102 static inline int max(int a, int b) {
    103     return (a>b) ? a : b;
    104 }
    105 
    106 /** scale each parameter by mul/div. Assume div isn't 0 */
    107 static inline void MULDIV(uint32_t *a, uint32_t *b, int mul, int div) {
    108     if (mul != div) {
    109         *a = (mul * *a) / div;
    110         *b = (mul * *b) / div;
    111     }
    112 }
    113 
    114 /** Determine the intersection of lhs & rhs store in out */
    115 static void intersect(struct copybit_rect_t *out,
    116                       const struct copybit_rect_t *lhs,
    117                       const struct copybit_rect_t *rhs) {
    118     out->l = max(lhs->l, rhs->l);
    119     out->t = max(lhs->t, rhs->t);
    120     out->r = min(lhs->r, rhs->r);
    121     out->b = min(lhs->b, rhs->b);
    122 }
    123 
    124 /** convert COPYBIT_FORMAT to MDP format */
    125 static int get_format(int format) {
    126     switch (format) {
    127         case HAL_PIXEL_FORMAT_RGB_565:       return MDP_RGB_565;
    128         case HAL_PIXEL_FORMAT_RGBX_8888:     return MDP_RGBX_8888;
    129         case HAL_PIXEL_FORMAT_RGB_888:       return MDP_RGB_888;
    130         case HAL_PIXEL_FORMAT_RGBA_8888:     return MDP_RGBA_8888;
    131         case HAL_PIXEL_FORMAT_BGRA_8888:     return MDP_BGRA_8888;
    132         case HAL_PIXEL_FORMAT_YCrCb_422_SP:  return MDP_Y_CRCB_H2V1;
    133         case HAL_PIXEL_FORMAT_YCrCb_420_SP:  return MDP_Y_CRCB_H2V2;
    134         case HAL_PIXEL_FORMAT_YCbCr_422_SP:  return MDP_Y_CBCR_H2V1;
    135         case HAL_PIXEL_FORMAT_YCbCr_420_SP:  return MDP_Y_CBCR_H2V2;
    136         case HAL_PIXEL_FORMAT_YCrCb_420_SP_ADRENO: return MDP_Y_CBCR_H2V2_ADRENO;
    137         case HAL_PIXEL_FORMAT_YCbCr_420_SP_VENUS: return MDP_Y_CBCR_H2V2_VENUS;
    138         case HAL_PIXEL_FORMAT_NV12_ENCODEABLE: return MDP_Y_CBCR_H2V2;
    139     }
    140     return -1;
    141 }
    142 
    143 /** convert from copybit image to mdp image structure */
    144 static void set_image(struct mdp_img *img, const struct copybit_image_t *rhs)
    145 {
    146     private_handle_t* hnd = (private_handle_t*)rhs->handle;
    147     if(hnd == NULL){
    148         ALOGE("copybit: Invalid handle");
    149         return;
    150     }
    151     img->width      = rhs->w;
    152     img->height     = rhs->h;
    153     img->format     = get_format(rhs->format);
    154     img->offset     = hnd->offset;
    155     img->memory_id  = hnd->fd;
    156 }
    157 /** setup rectangles */
    158 static void set_rects(struct copybit_context_t *dev,
    159                       struct mdp_blit_req *e,
    160                       const struct copybit_rect_t *dst,
    161                       const struct copybit_rect_t *src,
    162                       const struct copybit_rect_t *scissor,
    163                       uint32_t horiz_padding,
    164                       uint32_t vert_padding) {
    165     struct copybit_rect_t clip;
    166     intersect(&clip, scissor, dst);
    167 
    168     e->dst_rect.x  = clip.l;
    169     e->dst_rect.y  = clip.t;
    170     e->dst_rect.w  = clip.r - clip.l;
    171     e->dst_rect.h  = clip.b - clip.t;
    172 
    173     uint32_t W, H, delta_x, delta_y;
    174     if (dev->mFlags & COPYBIT_TRANSFORM_ROT_90) {
    175         delta_x = (clip.t - dst->t);
    176         delta_y = (dst->r - clip.r);
    177         e->src_rect.w = (clip.b - clip.t);
    178         e->src_rect.h = (clip.r - clip.l);
    179         W = dst->b - dst->t;
    180         H = dst->r - dst->l;
    181     } else {
    182         delta_x  = (clip.l - dst->l);
    183         delta_y  = (clip.t - dst->t);
    184         e->src_rect.w  = (clip.r - clip.l);
    185         e->src_rect.h  = (clip.b - clip.t);
    186         W = dst->r - dst->l;
    187         H = dst->b - dst->t;
    188     }
    189 
    190     MULDIV(&delta_x, &e->src_rect.w, src->r - src->l, W);
    191     MULDIV(&delta_y, &e->src_rect.h, src->b - src->t, H);
    192 
    193     e->src_rect.x = delta_x + src->l;
    194     e->src_rect.y = delta_y + src->t;
    195 
    196     if (dev->mFlags & COPYBIT_TRANSFORM_FLIP_V) {
    197         if (dev->mFlags & COPYBIT_TRANSFORM_ROT_90) {
    198             e->src_rect.x = (src->l + src->r) - (e->src_rect.x + e->src_rect.w);
    199         }else{
    200             e->src_rect.y = (src->t + src->b) - (e->src_rect.y + e->src_rect.h);
    201         }
    202     }
    203 
    204     if (dev->mFlags & COPYBIT_TRANSFORM_FLIP_H) {
    205         if (dev->mFlags & COPYBIT_TRANSFORM_ROT_90) {
    206             e->src_rect.y = (src->t + src->b) - (e->src_rect.y + e->src_rect.h);
    207         }else{
    208             e->src_rect.x = (src->l + src->r) - (e->src_rect.x + e->src_rect.w);
    209         }
    210     }
    211 }
    212 
    213 /** setup mdp request */
    214 static void set_infos(struct copybit_context_t *dev,
    215                       struct mdp_blit_req *req, int flags)
    216 {
    217     req->alpha = dev->mAlpha;
    218     req->transp_mask = MDP_TRANSP_NOP;
    219     req->flags = dev->mFlags | flags;
    220     // check if we are blitting to f/b
    221     if (COPYBIT_ENABLE == dev->mBlitToFB) {
    222         req->flags |= MDP_MEMORY_ID_TYPE_FB;
    223     }
    224 #if defined(COPYBIT_QSD8K)
    225     req->flags |= MDP_BLEND_FG_PREMULT;
    226 #endif
    227 }
    228 
    229 /** copy the bits */
    230 static int msm_copybit(struct copybit_context_t *dev, void const *list)
    231 {
    232     int err = ioctl(dev->mFD, MSMFB_ASYNC_BLIT,
    233                     (struct mdp_async_blit_req_list const*)list);
    234     ALOGE_IF(err<0, "copyBits failed (%s)", strerror(errno));
    235     if (err == 0) {
    236         return 0;
    237     } else {
    238 #if DEBUG_MDP_ERRORS
    239         struct mdp_async_blit_req_list const* l =
    240             (struct mdp_async_blit_req_list const*)list;
    241         for (unsigned int i=0 ; i<l->count ; i++) {
    242             ALOGE("%d: src={w=%d, h=%d, f=%d, rect={%d,%d,%d,%d}}\n"
    243                   "    dst={w=%d, h=%d, f=%d, rect={%d,%d,%d,%d}}\n"
    244                   "    flags=%08x"
    245                   ,
    246                   i,
    247                   l->req[i].src.width,
    248                   l->req[i].src.height,
    249                   l->req[i].src.format,
    250                   l->req[i].src_rect.x,
    251                   l->req[i].src_rect.y,
    252                   l->req[i].src_rect.w,
    253                   l->req[i].src_rect.h,
    254                   l->req[i].dst.width,
    255                   l->req[i].dst.height,
    256                   l->req[i].dst.format,
    257                   l->req[i].dst_rect.x,
    258                   l->req[i].dst_rect.y,
    259                   l->req[i].dst_rect.w,
    260                   l->req[i].dst_rect.h,
    261                   l->req[i].flags
    262                  );
    263         }
    264 #endif
    265         return -errno;
    266     }
    267 }
    268 
    269 /*****************************************************************************/
    270 
    271 /** Set a parameter to value */
    272 static int set_parameter_copybit(
    273     struct copybit_device_t *dev,
    274     int name,
    275     int value)
    276 {
    277     struct copybit_context_t* ctx = (struct copybit_context_t*)dev;
    278     int status = 0;
    279     if (ctx) {
    280         switch(name) {
    281             case COPYBIT_ROTATION_DEG:
    282                 switch (value) {
    283                     case 0:
    284                         ctx->mFlags &= ~0x7;
    285                         break;
    286                     case 90:
    287                         ctx->mFlags &= ~0x7;
    288                         ctx->mFlags |= MDP_ROT_90;
    289                         break;
    290                     case 180:
    291                         ctx->mFlags &= ~0x7;
    292                         ctx->mFlags |= MDP_ROT_180;
    293                         break;
    294                     case 270:
    295                         ctx->mFlags &= ~0x7;
    296                         ctx->mFlags |= MDP_ROT_270;
    297                         break;
    298                     default:
    299                         ALOGE("Invalid value for COPYBIT_ROTATION_DEG");
    300                         status = -EINVAL;
    301                         break;
    302                 }
    303                 break;
    304             case COPYBIT_PLANE_ALPHA:
    305                 if (value < 0)      value = MDP_ALPHA_NOP;
    306                 if (value >= 256)   value = 255;
    307                 ctx->mAlpha = value;
    308                 break;
    309             case COPYBIT_DITHER:
    310                 if (value == COPYBIT_ENABLE) {
    311                     ctx->mFlags |= MDP_DITHER;
    312                 } else if (value == COPYBIT_DISABLE) {
    313                     ctx->mFlags &= ~MDP_DITHER;
    314                 }
    315                 break;
    316             case COPYBIT_BLUR:
    317                 if (value == COPYBIT_ENABLE) {
    318                     ctx->mFlags |= MDP_BLUR;
    319                 } else if (value == COPYBIT_DISABLE) {
    320                     ctx->mFlags &= ~MDP_BLUR;
    321                 }
    322                 break;
    323             case COPYBIT_BLEND_MODE:
    324                 if(value == COPYBIT_BLENDING_PREMULT) {
    325                     ctx->mFlags |= MDP_BLEND_FG_PREMULT;
    326                 } else {
    327                     ctx->mFlags &= ~MDP_BLEND_FG_PREMULT;
    328                 }
    329                 break;
    330             case COPYBIT_TRANSFORM:
    331                 ctx->mFlags &= ~0x7;
    332                 ctx->mFlags |= value & 0x7;
    333                 break;
    334             case COPYBIT_BLIT_TO_FRAMEBUFFER:
    335                 if (COPYBIT_ENABLE == value) {
    336                     ctx->mBlitToFB = value;
    337                 } else if (COPYBIT_DISABLE == value) {
    338                     ctx->mBlitToFB = value;
    339                 } else {
    340                     ALOGE ("%s:Invalid input for COPYBIT_BLIT_TO_FRAMEBUFFER : %d",
    341                             __FUNCTION__, value);
    342                 }
    343                 break;
    344             case COPYBIT_FG_LAYER:
    345                 if(value == COPYBIT_ENABLE) {
    346                      ctx->mFlags |= MDP_IS_FG;
    347                 } else if (value == COPYBIT_DISABLE) {
    348                     ctx->mFlags &= ~MDP_IS_FG;
    349                 }
    350                 break ;
    351             default:
    352                 status = -EINVAL;
    353                 break;
    354         }
    355     } else {
    356         status = -EINVAL;
    357     }
    358     return status;
    359 }
    360 
    361 /** Get a static info value */
    362 static int get(struct copybit_device_t *dev, int name)
    363 {
    364     struct copybit_context_t* ctx = (struct copybit_context_t*)dev;
    365     int value;
    366     if (ctx) {
    367         switch(name) {
    368             case COPYBIT_MINIFICATION_LIMIT:
    369                 value = MAX_SCALE_FACTOR;
    370                 break;
    371             case COPYBIT_MAGNIFICATION_LIMIT:
    372                 value = MAX_SCALE_FACTOR;
    373                 break;
    374             case COPYBIT_SCALING_FRAC_BITS:
    375                 value = 32;
    376                 break;
    377             case COPYBIT_ROTATION_STEP_DEG:
    378                 value = 90;
    379                 break;
    380             default:
    381                 value = -EINVAL;
    382         }
    383     } else {
    384         value = -EINVAL;
    385     }
    386     return value;
    387 }
    388 
    389 static int set_sync_copybit(struct copybit_device_t *dev,
    390     int acquireFenceFd)
    391 {
    392     struct copybit_context_t* ctx = (struct copybit_context_t*)dev;
    393     if (acquireFenceFd != -1) {
    394         if (ctx->list.sync.acq_fen_fd_cnt < (MDP_MAX_FENCE_FD - 1)) {
    395             ctx->acqFence[ctx->list.sync.acq_fen_fd_cnt++] = acquireFenceFd;
    396         } else {
    397             int ret = -EINVAL;
    398             struct blitReq *list = &ctx->list;
    399 
    400             // Since fence is full kick off what is already in the list
    401             ret = msm_copybit(ctx, list);
    402             if (ret < 0) {
    403                 ALOGE("%s: Blit call failed", __FUNCTION__);
    404                 return -EINVAL;
    405             }
    406             list->count = 0;
    407             list->sync.acq_fen_fd_cnt = 0;
    408             ctx->acqFence[list->sync.acq_fen_fd_cnt++] = acquireFenceFd;
    409             ctx->relFence = -1;
    410         }
    411     }
    412     return 0;
    413 }
    414 
    415 /** do a stretch blit type operation */
    416 static int stretch_copybit(
    417     struct copybit_device_t *dev,
    418     struct copybit_image_t const *dst,
    419     struct copybit_image_t const *src,
    420     struct copybit_rect_t const *dst_rect,
    421     struct copybit_rect_t const *src_rect,
    422     struct copybit_region_t const *region)
    423 {
    424     struct copybit_context_t* ctx = (struct copybit_context_t*)dev;
    425     struct blitReq *list;
    426     int status = 0;
    427     private_handle_t *yv12_handle = NULL;
    428 
    429     if (ctx) {
    430         list = &ctx->list;
    431 
    432         if (ctx->mAlpha < 255) {
    433             switch (src->format) {
    434                 // we don't support plane alpha with RGBA formats
    435                 case HAL_PIXEL_FORMAT_RGBA_8888:
    436                 case HAL_PIXEL_FORMAT_BGRA_8888:
    437                     ALOGE ("%s : Unsupported Pixel format %d", __FUNCTION__,
    438                            src->format);
    439                     return -EINVAL;
    440             }
    441         }
    442 
    443         if (src_rect->l < 0 || (uint32_t)src_rect->r > src->w ||
    444             src_rect->t < 0 || (uint32_t)src_rect->b > src->h) {
    445             // this is always invalid
    446             ALOGE ("%s : Invalid source rectangle : src_rect l %d t %d r %d b %d",\
    447                    __FUNCTION__, src_rect->l, src_rect->t, src_rect->r, src_rect->b);
    448 
    449             return -EINVAL;
    450         }
    451 
    452         if (src->w > MAX_DIMENSION || src->h > MAX_DIMENSION) {
    453             ALOGE ("%s : Invalid source dimensions w %d h %d", __FUNCTION__, src->w, src->h);
    454             return -EINVAL;
    455         }
    456 
    457         if (dst->w > MAX_DIMENSION || dst->h > MAX_DIMENSION) {
    458             ALOGE ("%s : Invalid DST dimensions w %d h %d", __FUNCTION__, dst->w, dst->h);
    459             return -EINVAL;
    460         }
    461 
    462         if(src->format ==  HAL_PIXEL_FORMAT_YV12) {
    463             int usage =
    464             GRALLOC_USAGE_PRIVATE_IOMMU_HEAP | GRALLOC_USAGE_PRIVATE_UNCACHED;
    465             if (0 == alloc_buffer(&yv12_handle,src->w,src->h,
    466                                   src->format, usage)){
    467                 if(0 == convertYV12toYCrCb420SP(src,yv12_handle)){
    468                     (const_cast<copybit_image_t *>(src))->format =
    469                         HAL_PIXEL_FORMAT_YCrCb_420_SP;
    470                     (const_cast<copybit_image_t *>(src))->handle =
    471                         yv12_handle;
    472                     (const_cast<copybit_image_t *>(src))->base =
    473                         (void *)yv12_handle->base;
    474                 }
    475                 else{
    476                     ALOGE("Error copybit conversion from yv12 failed");
    477                     if(yv12_handle)
    478                         free_buffer(yv12_handle);
    479                     return -EINVAL;
    480                 }
    481             }
    482             else{
    483                 ALOGE("Error:unable to allocate memeory for yv12 software conversion");
    484                 return -EINVAL;
    485             }
    486         }
    487         const uint32_t maxCount = sizeof(list->req)/sizeof(list->req[0]);
    488         const struct copybit_rect_t bounds = { 0, 0, (int)dst->w, (int)dst->h };
    489         struct copybit_rect_t clip;
    490         status = 0;
    491         while ((status == 0) && region->next(region, &clip)) {
    492             intersect(&clip, &bounds, &clip);
    493             mdp_blit_req* req = &list->req[list->count];
    494             int flags = 0;
    495 
    496             private_handle_t* src_hnd = (private_handle_t*)src->handle;
    497             if(src_hnd != NULL && src_hnd->flags & private_handle_t::PRIV_FLAGS_DO_NOT_FLUSH) {
    498                 flags |=  MDP_BLIT_NON_CACHED;
    499             }
    500 
    501             set_infos(ctx, req, flags);
    502             set_image(&req->dst, dst);
    503             set_image(&req->src, src);
    504             set_rects(ctx, req, dst_rect, src_rect, &clip, src->horiz_padding, src->vert_padding);
    505 
    506             if (req->src_rect.w<=0 || req->src_rect.h<=0)
    507                 continue;
    508 
    509             if (req->dst_rect.w<=0 || req->dst_rect.h<=0)
    510                 continue;
    511 
    512             if (++list->count == maxCount) {
    513                 status = msm_copybit(ctx, list);
    514                 if (ctx->relFence != -1) {
    515                     list->sync.acq_fen_fd_cnt = 0;
    516                 }
    517                 list->count = 0;
    518             }
    519         }
    520         if(yv12_handle) {
    521             //Before freeing the buffer we need buffer passed through blit call
    522             if (list->count != 0) {
    523                 status = msm_copybit(ctx, list);
    524                 if (ctx->relFence != -1) {
    525                     list->sync.acq_fen_fd_cnt = 0;
    526                 }
    527                 list->count = 0;
    528             }
    529             free_buffer(yv12_handle);
    530         }
    531     } else {
    532         ALOGE ("%s : Invalid COPYBIT context", __FUNCTION__);
    533         status = -EINVAL;
    534     }
    535     return status;
    536 }
    537 
    538 /** Perform a blit type operation */
    539 static int blit_copybit(
    540     struct copybit_device_t *dev,
    541     struct copybit_image_t const *dst,
    542     struct copybit_image_t const *src,
    543     struct copybit_region_t const *region)
    544 {
    545     struct copybit_rect_t dr = { 0, 0, (int)dst->w, (int)dst->h };
    546     struct copybit_rect_t sr = { 0, 0, (int)src->w, (int)src->h };
    547     return stretch_copybit(dev, dst, src, &dr, &sr, region);
    548 }
    549 
    550 static int finish_copybit(struct copybit_device_t *dev)
    551 {
    552     // NOP for MDP copybit
    553     return 0;
    554 }
    555 
    556 /*****************************************************************************/
    557 
    558 /** Close the copybit device */
    559 static int close_copybit(struct hw_device_t *dev)
    560 {
    561     struct copybit_context_t* ctx = (struct copybit_context_t*)dev;
    562     if (ctx) {
    563         close(ctx->mFD);
    564         free(ctx);
    565     }
    566     return 0;
    567 }
    568 
    569 static int flush_get_fence(struct copybit_device_t *dev, int* fd)
    570 {
    571     struct copybit_context_t* ctx = (struct copybit_context_t*)dev;
    572     struct blitReq *list = &ctx->list;
    573     int ret = -EINVAL;
    574 
    575     if (list->count) {
    576         ret = msm_copybit(ctx, list);
    577         if (ret < 0)
    578             ALOGE("%s: Blit call failed", __FUNCTION__);
    579         list->count = 0;
    580     }
    581     *fd = ctx->relFence;
    582     list->sync.acq_fen_fd_cnt = 0;
    583     ctx->relFence = -1;
    584     return ret;
    585 }
    586 
    587 /** Open a new instance of a copybit device using name */
    588 static int open_copybit(const struct hw_module_t* module, const char* name,
    589                         struct hw_device_t** device)
    590 {
    591     int status = -EINVAL;
    592     copybit_context_t *ctx;
    593     ctx = (copybit_context_t *)malloc(sizeof(copybit_context_t));
    594     memset(ctx, 0, sizeof(*ctx));
    595 
    596     ctx->device.common.tag = HARDWARE_DEVICE_TAG;
    597     ctx->device.common.version = 1;
    598     ctx->device.common.module = const_cast<hw_module_t*>(module);
    599     ctx->device.common.close = close_copybit;
    600     ctx->device.set_parameter = set_parameter_copybit;
    601     ctx->device.get = get;
    602     ctx->device.blit = blit_copybit;
    603     ctx->device.set_sync = set_sync_copybit;
    604     ctx->device.stretch = stretch_copybit;
    605     ctx->device.finish = finish_copybit;
    606     ctx->device.flush_get_fence = flush_get_fence;
    607     ctx->mAlpha = MDP_ALPHA_NOP;
    608     ctx->mFlags = 0;
    609     ctx->sync.flags = 0;
    610     ctx->sync.acq_fen_fd = ctx->acqFence;
    611     ctx->sync.rel_fen_fd = &ctx->relFence;
    612     ctx->list.count = 0;
    613     ctx->list.sync.acq_fen_fd_cnt = 0;
    614     ctx->list.sync.rel_fen_fd = ctx->sync.rel_fen_fd;
    615     ctx->list.sync.acq_fen_fd = ctx->sync.acq_fen_fd;
    616     ctx->mFD = open("/dev/graphics/fb0", O_RDWR, 0);
    617     if (ctx->mFD < 0) {
    618         status = errno;
    619         ALOGE("Error opening frame buffer errno=%d (%s)",
    620               status, strerror(status));
    621         status = -status;
    622     } else {
    623         status = 0;
    624         *device = &ctx->device.common;
    625     }
    626     return status;
    627 }
    628