include/linux/omap_v4l2_gfx.h

   1 /*
   2  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
   3  *
   4  * This file is licensed under the terms of the GNU General Public License
   5  * version 2. This program is licensed "as is" without any warranty of any
   6  * kind, whether express or implied.
   7  *
   8  * This file specifies the custom ioctl API between a client "consumer"
   9  * process and the V4L2-GFX driver. The consumer process should only use
  10  * these APIs and will typically/ultimately be a GL application.
  11  *
  12  * There will also be a "producer" process which queues multimedia
  13  * content to the driver, however, this will only use standard V4L2 APIs.
  14  */
  15
  16 #ifndef _OMAP_V4L2_GFX_H_
  17 #define _OMAP_V4L2_GFX_H_
  18
  19 #include <linux/videodev.h>
  20
  21 /*
  22  * @see V4L2_GFX_IOC_CONSUMER, struct v4l2_gfx_consumer_params
  23  */
  24 enum v4l2_gfx_consumer_type {
  25         /*
  26          * Wait for the producer process to activate a video stream
  27          */
  28         V4L2_GFX_CONSUMER_WAITSTREAM,
  29         };
  30
  31 /*
  32  * @see V4L2_GFX_IOC_CONSUMER
  33  */
  34 struct v4l2_gfx_consumer_params {
  35         /*
  36          * @see v4l2_gfx_consumer_type
  37          */
  38         int type;                       /* w */
  39         /*
  40          * If the consumer process is waiting the ioctl will block until the
  41          * timeout expires or the expected event occurs, see the type field
  42          */
  43         unsigned int timeout_ms;        /* w */
  44         /*
  45          * If acquire_timeout_ms > 0 and no streaming activity has been detected
  46          * for acquire_timeout_ms milliseconds the V4L2_GFX_IOC_ACQ ioctl will
  47          * return with ETIMEOUT
  48          */
  49         unsigned int acquire_timeout_ms;        /* w */
  50 };
  51
  52 /*
  53  * @see V4L2_GFX_IOC_INFO
  54  */
  55 struct v4l2_gfx_info_params {
  56
  57         /*
  58          * Return how many times the device has been opened, this number will
  59          * decrement when the device is closed.
  60          *
  61          * One use for this might be to detect if a consumer or producer is
  62          * active and in the process of setting up a stream. However this could
  63          * be unreliable if the processes are in the process of closing / crashing.
  64          *
  65          * Obviously this value will always be at least one i.e. the process
  66          * issuing the ioctl opens the device.
  67          */
  68         unsigned int opencnt;                   /* r */
  69
  70 };
  71
  72 /*
  73  * @see V4L2_GFX_IOC_PRODUCER
  74  */
  75 struct v4l2_gfx_producer_params {
  76         /*
  77          * If set mark the producer side as open, if not set mark as closed.
  78          * For Android we need this because the mediaserver won't close the
  79          * driver.
  80          */
  81         #define V4L2_GFX_PRODUCER_MASK_OPEN     0x1
  82         unsigned int flags;                             /* w */
  83 };
  84
  85 struct v4l2_gfx_buf_params {
  86         /*
  87          * Buffer index.
  88          *
  89          * On acquire, when the ioctl returns the bufid field will be filled in
  90          * with the next buffer with data available.
  91          *
  92          * On release, the consumer process just specifies the buffer to release
  93          * which usually is the last acquired buffer index.
  94          */
  95     int bufid;  /* r/w */
  96
  97         /*
  98          * Cropping information
  99          * For the acquire ioctl only
 100          */
 101         int crop_top;           /* r */
 102         int crop_left;          /* r */
 103         int crop_width;         /* r */
 104         int crop_height;        /* r */
 105 };
 106
 107 /*
 108  * This ioctl should be issued once by the consumer process before starting
 109  * any rendering loop. It allows the process to wait for the producer process
 110  * to become ready.
 111  *
 112  * @see struct v4l2_gfx_consumer_params
 113  *
 114  * Return value:
 115  *              Returns 0 if successful, or -1 on error, in which case errno indicates
 116  *              the error.
 117  */
 118 #define V4L2_GFX_IOC_CONSUMER _IOWR ('v', BASE_VIDIOCPRIVATE+0, \
 119                                                                         struct v4l2_gfx_consumer_params)
 120
 121 /*
 122  * Acquire the buffer to be rendered and its properties.
 123  *
 124  * @see struct v4l2_gfx_buf_params
 125  *
 126  * Return value:
 127  *              Returns 0 if successful, or -1 on error, in which case errno indicates
 128  *              the error.
 129  *
 130  *              ETIMEDOUT       If acquire_timeout_ms is set via V4L2_GFX_IOC_CONSUMER
 131  *                                      this error code can be returned.
 132  *              ENODEV          If the producer side of the stream stops this error will
 133  *                                      be returned.
 134  */
 135 #define V4L2_GFX_IOC_ACQ _IOR ('v', BASE_VIDIOCPRIVATE+1, \
 136                                                                         struct v4l2_gfx_buf_params)
 137
 138 /*
 139  * Release the buffer that was rendered
 140  *
 141  * @see struct v4l2_gfx_buf_params
 142  *
 143  * Return value:
 144  *              Returns 0 if successful, or -1 on error, in which case errno indicates
 145  *              the error.
 146  *
 147  *              ETIMEDOUT       It took longer than 16ms for the app to render the frame
 148  *                                      (This will probably go away to avoid render loop stalls)
 149  *              EINVAL          Attempted to release an invalid buffer index.
 150  */
 151 #define V4L2_GFX_IOC_REL _IOW ('v', BASE_VIDIOCPRIVATE+2, \
 152                                                                         struct v4l2_gfx_buf_params)
 153
 154 /*
 155  * Ioctl used to get information about the device
 156  *
 157  * @see struct v4l2_gfx_info_params
 158  *
 159  * Return value:
 160  *              Returns 0 if successful, or -1 on error, in which case errno indicates
 161  *              the error.
 162  */
 163 #define V4L2_GFX_IOC_INFO _IOWR ('v', BASE_VIDIOCPRIVATE+3, \
 164                                                                         struct v4l2_gfx_info_params)
 165
 166 /*
 167  * Ioctl used to set producer params
 168  *
 169  * @see struct v4l2_gfx_producer_params
 170  *
 171  * Return value:
 172  *              Returns 0 if successful, or -1 on error, in which case errno indicates
 173  *              the error.
 174  */
 175 #define V4L2_GFX_IOC_PRODUCER _IOWR ('v', BASE_VIDIOCPRIVATE+4, \
 176                                                                         struct v4l2_gfx_producer_params)
 177 #endif  // _OMAP_V4L2_GFX_H_