drivers: media: i2c: imx708: Fix WIDE_DYNAMIC_RANGE control with long exposure

Setting V4L2_CID_WIDE_DYNAMIC_RANGE was causing the long exposure
shift count to be reset, which is incorrect if the user has already
changed the frame length to cause it to have a non-zero value.

Because it only updates control ranges and doesn't set any registers,
the control can also be applied when the sensor is not powered on.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>

diff --git a/drivers/media/i2c/imx708.c b/drivers/media/i2c/imx708.c
index 038f9e2..7b7a70a 100644 (file)
--- a/drivers/media/i2c/imx708.c
+++ b/drivers/media/i2c/imx708.c
@@ -171,7 +171,7 @@ struct imx708_mode {
        /* Not all modes have the same exposure lines step. */
        u32 exposure_lines_step;
 
-       /* HDR flag, currently not used at runtime */
+       /* HDR flag, used for checking if the current mode is HDR */
        bool hdr;
 };
 
@@ -1060,9 +1060,6 @@ static void imx708_set_framing_limits(struct imx708 *imx708)
        unsigned int hblank;
        const struct imx708_mode *mode = imx708->mode;
 
-       /* Default to no long exposure multiplier */
-       imx708->long_exp_shift = 0;
-
        __v4l2_ctrl_modify_range(imx708->pixel_rate,
                                 mode->pixel_rate, mode->pixel_rate,
                                 1, mode->pixel_rate);
@@ -1091,12 +1088,33 @@ static int imx708_set_ctrl(struct v4l2_ctrl *ctrl)
        unsigned int code, num_modes;
        int ret = 0;
 
-       /*
-        * The VBLANK control may change the limits of usable exposure, so check
-        * and adjust if necessary.
-        */
-       if (ctrl->id == V4L2_CID_VBLANK)
+       switch (ctrl->id) {
+       case V4L2_CID_VBLANK:
+               /*
+                * The VBLANK control may change the limits of usable exposure,
+                * so check and adjust if necessary.
+                */
                imx708_adjust_exposure_range(imx708, ctrl);
+               break;
+
+       case V4L2_CID_WIDE_DYNAMIC_RANGE:
+               /*
+                * The WIDE_DYNAMIC_RANGE control can also be applied immediately
+                * as it doesn't set any registers. Don't do anything if the mode
+                * already matches.
+                */
+               if (imx708->mode && imx708->mode->hdr != ctrl->val) {
+                       code = imx708_get_format_code(imx708);
+                       get_mode_table(code, &mode_list, &num_modes, ctrl->val);
+                       imx708->mode = v4l2_find_nearest_size(mode_list,
+                                                             num_modes,
+                                                             width, height,
+                                                             imx708->mode->width,
+                                                             imx708->mode->height);
+                       imx708_set_framing_limits(imx708);
+               }
+               break;
+       }
 
        /*
         * Applying V4L2 control value only happens
@@ -1158,14 +1176,7 @@ static int imx708_set_ctrl(struct v4l2_ctrl *ctrl)
                                       imx708->notify_gains->p_new.p_u32[3]);
                break;
        case V4L2_CID_WIDE_DYNAMIC_RANGE:
-               code = imx708_get_format_code(imx708);
-               get_mode_table(code, &mode_list, &num_modes, ctrl->val);
-               imx708->mode = v4l2_find_nearest_size(mode_list,
-                                                     num_modes,
-                                                     width, height,
-                                                     imx708->mode->width,
-                                                     imx708->mode->height);
-               imx708_set_framing_limits(imx708);
+               /* Already handled above. */
                break;
        default:
                dev_info(&client->dev,