[media] m5mols: Add exposure bias control

Add integer menu control for exposure bias. The control value range is
-2.0 EV to +2.0 EV, in 0.5 EV steps.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 25 insertions, 3 deletions

diff --git a/drivers/media/video/m5mols/m5mols.h b/drivers/media/video/m5mols/m5mols.h
index fa1f2c145852..03421fc1a965 100644
--- a/drivers/media/video/m5mols/m5mols.h
+++ b/drivers/media/video/m5mols/m5mols.h
@@ -161,6 +161,7 @@ struct m5mols_version {
  * @flags: state variable for the interrupt handler
  * @handle: control handler
  * @auto_exposure: auto/manual exposure control
+ * @exposure_bias: exposure compensation control
  * @exposure: manual exposure control
  * @auto_iso: auto/manual ISO sensitivity control
  * @iso: manual ISO sensitivity control
@@ -191,8 +192,9 @@ struct m5mols_info {
 
         struct v4l2_ctrl_handler handle;
         struct {
-                /* exposure/auto-exposure cluster */
+                /* exposure/exposure bias/auto exposure cluster */
                 struct v4l2_ctrl *auto_exposure;
+                struct v4l2_ctrl *exposure_bias;
                 struct v4l2_ctrl *exposure;
         };
         struct {
diff --git a/drivers/media/video/m5mols/m5mols_controls.c b/drivers/media/video/m5mols/m5mols_controls.c
index 1ab21f0afa8a..797836315225 100644
--- a/drivers/media/video/m5mols/m5mols_controls.c
+++ b/drivers/media/video/m5mols/m5mols_controls.c
@@ -241,6 +241,11 @@ static int m5mols_set_exposure(struct m5mols_info *info, int exposure)
                 ret = m5mols_write(sd, AE_MODE, REG_AE_ALL);
                 if (ret < 0)
                         return ret;
+
+                v4l2_dbg(1, m5mols_debug, sd, "%s: exposure bias: %#x\n",
+                         __func__, info->exposure_bias->val);
+
+                return m5mols_write(sd, AE_INDEX, info->exposure_bias->val);
         }
 
         if (exposure == V4L2_EXPOSURE_MANUAL) {
@@ -251,6 +256,9 @@ static int m5mols_set_exposure(struct m5mols_info *info, int exposure)
                 if (ret == 0)
                         ret = m5mols_write(sd, AE_MAN_GAIN_CAP,
                                            info->exposure->val);
+
+                v4l2_dbg(1, m5mols_debug, sd, "%s: exposure: %#x\n",
+                         __func__, info->exposure->val);
         }
 
         return ret;
@@ -447,6 +455,12 @@ static const s64 iso_qmenu[] = {
         50, 100, 200, 400, 800, 1600, 3200
 };
 
+/* Supported Exposure Bias values, -2.0EV...+2.0EV */
+static const s64 ev_bias_qmenu[] = {
+        /* AE_INDEX: 0x00...0x08 */
+        -2000, -1500, -1000, -500, 0, 500, 1000, 1500, 2000
+};
+
 int m5mols_init_controls(struct v4l2_subdev *sd)
 {
         struct m5mols_info *info = to_m5mols(sd);
@@ -467,6 +481,7 @@ int m5mols_init_controls(struct v4l2_subdev *sd)
                         &m5mols_ctrl_ops, V4L2_CID_AUTO_N_PRESET_WHITE_BALANCE,
                         9, ~0x3fe, V4L2_WHITE_BALANCE_AUTO);
 
+        /* Exposure control cluster */
         info->auto_exposure = v4l2_ctrl_new_std_menu(&info->handle,
                         &m5mols_ctrl_ops, V4L2_CID_EXPOSURE_AUTO,
                         1, ~0x03, V4L2_EXPOSURE_AUTO);
@@ -475,6 +490,12 @@ int m5mols_init_controls(struct v4l2_subdev *sd)
                         &m5mols_ctrl_ops, V4L2_CID_EXPOSURE,
                         0, exposure_max, 1, exposure_max / 2);
 
+        info->exposure_bias = v4l2_ctrl_new_int_menu(&info->handle,
+                        &m5mols_ctrl_ops, V4L2_CID_AUTO_EXPOSURE_BIAS,
+                        ARRAY_SIZE(ev_bias_qmenu) - 1,
+                        ARRAY_SIZE(ev_bias_qmenu)/2 - 1,
+                        ev_bias_qmenu);
+
         /* ISO control cluster */
         info->auto_iso = v4l2_ctrl_new_std_menu(&info->handle, &m5mols_ctrl_ops,
                         V4L2_CID_ISO_SENSITIVITY_AUTO, 1, ~0x03, 1);
@@ -499,8 +520,7 @@ int m5mols_init_controls(struct v4l2_subdev *sd)
                 return ret;
         }
 
-        v4l2_ctrl_auto_cluster(2, &info->auto_exposure, 1, false);
-
+        v4l2_ctrl_auto_cluster(3, &info->auto_exposure, 1, false);
         info->auto_iso->flags |= V4L2_CTRL_FLAG_VOLATILE |
                                 V4L2_CTRL_FLAG_UPDATE;
         v4l2_ctrl_auto_cluster(2, &info->auto_iso, 0, false);