target/linux/bcm27xx/patches-6.1/950-0533-drivers-media-imx708-Enable-long-exposure-mode.patch

   1 From 321814f1f361336278e9d682492152098b0a0f00 Mon Sep 17 00:00:00 2001
   2 From: Naushir Patuck <naush@raspberrypi.com>
   3 Date: Thu, 5 Jan 2023 14:44:48 +0000
   4 Subject: [PATCH] drivers: media: imx708: Enable long exposure mode
   5
   6 Enable long exposure modes by using the long exposure shift register setting
   7 in the imx708 sensor.
   8
   9 Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
  10 ---
  11  drivers/media/i2c/imx708.c | 41 +++++++++++++++++++++++++++++++++-----
  12  1 file changed, 36 insertions(+), 5 deletions(-)
  13
  14 --- a/drivers/media/i2c/imx708.c
  15 +++ b/drivers/media/i2c/imx708.c
  16 @@ -44,6 +44,10 @@
  17  #define IMX708_REG_FRAME_LENGTH                0x0340
  18  #define IMX708_FRAME_LENGTH_MAX                0xffff
  19
  20 +/* Long exposure multiplier */
  21 +#define IMX708_LONG_EXP_SHIFT_MAX      7
  22 +#define IMX708_LONG_EXP_SHIFT_REG      0x3100
  23 +
  24  /* Exposure control */
  25  #define IMX708_REG_EXPOSURE            0x0202
  26  #define IMX708_EXPOSURE_OFFSET         48
  27 @@ -806,6 +810,9 @@ struct imx708 {
  28
  29         /* Rewrite common registers on stream on? */
  30         bool common_regs_written;
  31 +
  32 +       /* Current long exposure factor in use. Set through V4L2_CID_VBLANK */
  33 +       unsigned int long_exp_shift;
  34  };
  35
  36  static inline struct imx708 *to_imx708(struct v4l2_subdev *_sd)
  37 @@ -994,7 +1001,8 @@ static int imx708_set_exposure(struct im
  38          * will automatically divide the medium and short ones by 4,16.
  39          */
  40         ret = imx708_write_reg(imx708, IMX708_REG_EXPOSURE,
  41 -                              IMX708_REG_VALUE_16BIT, val);
  42 +                              IMX708_REG_VALUE_16BIT,
  43 +                              val >> imx708->long_exp_shift);
  44
  45         return ret;
  46  }
  47 @@ -1027,18 +1035,42 @@ static int imx708_set_analogue_gain(stru
  48         return ret;
  49  }
  50
  51 +static int imx708_set_frame_length(struct imx708 *imx708, unsigned int val)
  52 +{
  53 +       int ret = 0;
  54 +
  55 +       imx708->long_exp_shift = 0;
  56 +
  57 +       while (val > IMX708_FRAME_LENGTH_MAX) {
  58 +               imx708->long_exp_shift++;
  59 +               val >>= 1;
  60 +       }
  61 +
  62 +       ret = imx708_write_reg(imx708, IMX708_REG_FRAME_LENGTH,
  63 +                              IMX708_REG_VALUE_16BIT, val);
  64 +       if (ret)
  65 +               return ret;
  66 +
  67 +       return imx708_write_reg(imx708, IMX708_LONG_EXP_SHIFT_REG,
  68 +                               IMX708_REG_VALUE_08BIT, imx708->long_exp_shift);
  69 +}
  70 +
  71  static void imx708_set_framing_limits(struct imx708 *imx708)
  72  {
  73         unsigned int hblank;
  74         const struct imx708_mode *mode = imx708->mode;
  75
  76 +       /* Default to no long exposure multiplier */
  77 +       imx708->long_exp_shift = 0;
  78 +
  79         __v4l2_ctrl_modify_range(imx708->pixel_rate,
  80                                  mode->pixel_rate, mode->pixel_rate,
  81                                  1, mode->pixel_rate);
  82
  83         /* Update limits and set FPS to default */
  84         __v4l2_ctrl_modify_range(imx708->vblank, mode->vblank_min,
  85 -                                IMX708_FRAME_LENGTH_MAX - mode->height,
  86 +                                ((1 << IMX708_LONG_EXP_SHIFT_MAX) *
  87 +                                       IMX708_FRAME_LENGTH_MAX) - mode->height,
  88                                  1, mode->vblank_default);
  89
  90         /*
  91 @@ -1112,9 +1144,8 @@ static int imx708_set_ctrl(struct v4l2_c
  92                                        imx708->vflip->val << 1);
  93                 break;
  94         case V4L2_CID_VBLANK:
  95 -               ret = imx708_write_reg(imx708, IMX708_REG_FRAME_LENGTH,
  96 -                                      IMX708_REG_VALUE_16BIT,
  97 -                                      imx708->mode->height + ctrl->val);
  98 +               ret = imx708_set_frame_length(imx708,
  99 +                                             imx708->mode->height + ctrl->val);
 100                 break;
 101         case V4L2_CID_NOTIFY_GAINS:
 102                 ret = imx708_write_reg(imx708, IMX708_REG_COLOUR_BALANCE_BLUE,