[PATCH v4 13/20] media: i2c: ov4689: Implement digital gain control

From: Mikhail Rudenko
Date: Tue Apr 02 2024 - 12:49:50 EST


The OV4689 sensor supports digital gain up to 16x. Implement
corresponding control in the driver. Default digital gain value is not
modified by this patch.

Signed-off-by: Mikhail Rudenko <mike.rudenko@xxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/i2c/ov4689.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/ov4689.c b/drivers/media/i2c/ov4689.c
index 60c60bbfe3bb..d6be0856afe1 100644
--- a/drivers/media/i2c/ov4689.c
+++ b/drivers/media/i2c/ov4689.c
@@ -35,6 +35,12 @@
#define OV4689_GAIN_STEP 1
#define OV4689_GAIN_DEFAULT 0x80

+#define OV4689_REG_DIG_GAIN CCI_REG16(0x352a)
+#define OV4689_DIG_GAIN_MIN 1
+#define OV4689_DIG_GAIN_MAX 0x7fff
+#define OV4689_DIG_GAIN_STEP 1
+#define OV4689_DIG_GAIN_DEFAULT 0x800
+
#define OV4689_REG_HTS CCI_REG16(0x380c)
#define OV4689_HTS_DIVIDER 4
#define OV4689_HTS_MAX 0x7fff
@@ -131,7 +137,6 @@ static const struct cci_reg_sequence ov4689_2688x1520_regs[] = {

/* AEC PK */
{CCI_REG8(0x3503), 0x04}, /* AEC_MANUAL gain_input_as_sensor_gain_format = 1 */
- {CCI_REG8(0x352a), 0x08}, /* DIG_GAIN_FRAC_LONG dig_gain_long[14:8] = 0x08 (2x) */

/* ADC and analog control*/
{CCI_REG8(0x3603), 0x40},
@@ -624,6 +629,9 @@ static int ov4689_set_ctrl(struct v4l2_ctrl *ctrl)
OV4689_TIMING_FLIP_MASK,
ctrl->val ? 0 : OV4689_TIMING_FLIP_BOTH, &ret);
break;
+ case V4L2_CID_DIGITAL_GAIN:
+ cci_write(regmap, OV4689_REG_DIG_GAIN, ctrl->val, &ret);
+ break;
default:
dev_warn(dev, "%s Unhandled id:0x%x, val:0x%x\n",
__func__, ctrl->id, ctrl->val);
@@ -654,7 +662,7 @@ static int ov4689_initialize_controls(struct ov4689 *ov4689)

handler = &ov4689->ctrl_handler;
mode = ov4689->cur_mode;
- ret = v4l2_ctrl_handler_init(handler, 12);
+ ret = v4l2_ctrl_handler_init(handler, 13);
if (ret)
return ret;

@@ -697,6 +705,10 @@ static int ov4689_initialize_controls(struct ov4689 *ov4689)
v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_VFLIP, 0, 1, 1, 0);
v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_HFLIP, 0, 1, 1, 0);

+ v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_DIGITAL_GAIN,
+ OV4689_DIG_GAIN_MIN, OV4689_DIG_GAIN_MAX,
+ OV4689_DIG_GAIN_STEP, OV4689_DIG_GAIN_DEFAULT);
+
if (handler->error) {
ret = handler->error;
dev_err(ov4689->dev, "Failed to init controls(%d)\n", ret);
--
2.44.0