target/linux/bcm27xx/patches-5.15/950-0486-staging-bcm2835-codec-Change-the-default-codec-res-t.patch

   1 From ac2682411d03cf2951abf2856aeaf10206e700fc Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.com>
   3 Date: Thu, 13 May 2021 11:56:21 +0100
   4 Subject: [PATCH] staging/bcm2835-codec: Change the default codec res
   5  to 32x32
   6
   7 In order to effectively guarantee that a V4L2_EVENT_SOURCE_CHANGE
   8 event occurs, adopt a default resolution of 32x32 so that it
   9 is incredibly unlikely to be decoding a stream of that resolution
  10 and therefore failing to note a "change" requiring the event.
  11
  12 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
  13 ---
  14  .../bcm2835-codec/bcm2835-v4l2-codec.c            | 15 +++++++++++++--
  15  1 file changed, 13 insertions(+), 2 deletions(-)
  16
  17 --- a/drivers/staging/vc04_services/bcm2835-codec/bcm2835-v4l2-codec.c
  18 +++ b/drivers/staging/vc04_services/bcm2835-codec/bcm2835-v4l2-codec.c
  19 @@ -97,8 +97,19 @@ static const char * const components[] =
  20  #define MAX_W          1920
  21  #define MAX_H          1920
  22  #define BPL_ALIGN      32
  23 -#define DEFAULT_WIDTH  640
  24 -#define DEFAULT_HEIGHT 480
  25 +/*
  26 + * The decoder spec supports the V4L2_EVENT_SOURCE_CHANGE event, but the docs
  27 + * seem to want it to always be generated on startup, which prevents the client
  28 + * from configuring the CAPTURE queue based on any parsing it has already done
  29 + * which may save time and allow allocation of CAPTURE buffers early. Surely
  30 + * SOURCE_CHANGE means something has changed, not just "always notify".
  31 + *
  32 + * For those clients that don't set the CAPTURE resolution, adopt a default
  33 + * resolution that is seriously unlikely to be correct, therefore almost
  34 + * guaranteed to get the SOURCE_CHANGE event.
  35 + */
  36 +#define DEFAULT_WIDTH  32
  37 +#define DEFAULT_HEIGHT 32
  38  /*
  39   * The unanswered question - what is the maximum size of a compressed frame?
  40   * V4L2 mandates that the encoded frame must fit in a single buffer. Sizing