[PATCH v2 2/5] media: ov5640: fix auto gain & exposure when changing mode

Hugues Fruchet
2018-08-13T13:01:52Z

Ensure that auto gain and auto exposure are well restored
when changing mode.

Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
---
drivers/media/i2c/ov5640.c | 96 ++++++++++++++++++++++++++--------------------
1 file changed, 54 insertions(+), 42 deletions(-)

diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
index 4b9da8b..7c569de 100644
--- a/drivers/media/i2c/ov5640.c
+++ b/drivers/media/i2c/ov5640.c
@@ -1000,6 +1000,18 @@ static int ov5640_get_gain(struct ov5640_dev *sensor)
return gain & 0x3ff;
}

+static int ov5640_set_gain(struct ov5640_dev *sensor, int gain)
+{
+ return ov5640_write_reg16(sensor, OV5640_REG_AEC_PK_REAL_GAIN,
+ (u16)gain & 0x3ff);
+}
+
+static int ov5640_set_autogain(struct ov5640_dev *sensor, bool on)
+{
+ return ov5640_mod_reg(sensor, OV5640_REG_AEC_PK_MANUAL,
+ BIT(1), on ? 0 : BIT(1));
+}
+
static int ov5640_set_stream_dvp(struct ov5640_dev *sensor, bool on)
{
int ret;
@@ -1577,7 +1589,7 @@ static int ov5640_set_mode_exposure_calc(struct ov5640_dev *sensor,
}

/* set capture gain */
- ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.gain, cap_gain16);
+ ret = ov5640_set_gain(sensor, cap_gain16);
if (ret)
return ret;

@@ -1590,7 +1602,7 @@ static int ov5640_set_mode_exposure_calc(struct ov5640_dev *sensor,
}

/* set exposure */
- return __v4l2_ctrl_s_ctrl(sensor->ctrls.exposure, cap_shutter);
+ return ov5640_set_exposure(sensor, cap_shutter);
}

/*
@@ -1598,26 +1610,13 @@ static int ov5640_set_mode_exposure_calc(struct ov5640_dev *sensor,
* change mode directly
*/
static int ov5640_set_mode_direct(struct ov5640_dev *sensor,
- const struct ov5640_mode_info *mode,
- bool auto_exp)
+ const struct ov5640_mode_info *mode)
{
- int ret;
-
if (!mode->reg_data)
return -EINVAL;

/* Write capture setting */
- ret = ov5640_load_regs(sensor, mode);
- if (ret < 0)
- return ret;
-
- /* turn auto gain/exposure back on for direct mode */
- ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_gain, 1);
- if (ret)
- return ret;
-
- return __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_exp, auto_exp ?
- V4L2_EXPOSURE_AUTO : V4L2_EXPOSURE_MANUAL);
+ return ov5640_load_regs(sensor, mode);
}

static int ov5640_set_mode(struct ov5640_dev *sensor,
@@ -1625,6 +1624,7 @@ static int ov5640_set_mode(struct ov5640_dev *sensor,
{
const struct ov5640_mode_info *mode = sensor->current_mode;
enum ov5640_downsize_mode dn_mode, orig_dn_mode;
+ bool auto_gain = sensor->ctrls.auto_gain->val == 1;
bool auto_exp = sensor->ctrls.auto_exp->val == V4L2_EXPOSURE_AUTO;
int ret;

@@ -1632,19 +1632,23 @@ static int ov5640_set_mode(struct ov5640_dev *sensor,
orig_dn_mode = orig_mode->dn_mode;

/* auto gain and exposure must be turned off when changing modes */
- ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.auto_gain, 0);
- if (ret)
- return ret;
+ if (auto_gain) {
+ ret = ov5640_set_autogain(sensor, false);
+ if (ret)
+ return ret;
+ }

- ret = ov5640_set_autoexposure(sensor, false);
- if (ret)
- return ret;
+ if (auto_exp) {
+ ret = ov5640_set_autoexposure(sensor, false);
+ if (ret)
+ goto restore_auto_gain;
+ }

if ((dn_mode == SUBSAMPLING && orig_dn_mode == SCALING) ||
(dn_mode == SCALING && orig_dn_mode == SUBSAMPLING)) {
/*
* change between subsampling and scaling
- * go through exposure calucation
+ * go through exposure calculation
*/
ret = ov5640_set_mode_exposure_calc(sensor, mode);
} else {
@@ -1652,11 +1656,16 @@ static int ov5640_set_mode(struct ov5640_dev *sensor,
* change inside subsampling or scaling
* download firmware directly
*/
- ret = ov5640_set_mode_direct(sensor, mode, auto_exp);
+ ret = ov5640_set_mode_direct(sensor, mode);
}
-
if (ret < 0)
- return ret;
+ goto restore_auto_exp_gain;
+
+ /* restore auto gain and exposure */
+ if (auto_gain)
+ ov5640_set_autogain(sensor, true);
+ if (auto_exp)
+ ov5640_set_autoexposure(sensor, true);

ret = ov5640_set_timings(sensor, mode);
if (ret < 0)
@@ -1681,6 +1690,15 @@ static int ov5640_set_mode(struct ov5640_dev *sensor,
sensor->pending_mode_change = false;

return 0;
+
+restore_auto_exp_gain:
+ if (auto_exp)
+ ov5640_set_autoexposure(sensor, true);
+restore_auto_gain:
+ if (auto_gain)
+ ov5640_set_autogain(sensor, true);
+
+ return ret;
}

static int ov5640_set_framefmt(struct ov5640_dev *sensor,
@@ -2141,20 +2159,20 @@ static int ov5640_set_ctrl_white_balance(struct ov5640_dev *sensor, int awb)
return ret;
}

-static int ov5640_set_ctrl_exposure(struct ov5640_dev *sensor, int exp)
+static int ov5640_set_ctrl_exposure(struct ov5640_dev *sensor,
+ enum v4l2_exposure_auto_type auto_exposure)
{
struct ov5640_ctrls *ctrls = &sensor->ctrls;
- bool auto_exposure = (exp == V4L2_EXPOSURE_AUTO);
+ bool auto_exp = (auto_exposure == V4L2_EXPOSURE_AUTO);
int ret = 0;

if (ctrls->auto_exp->is_new) {
- ret = ov5640_mod_reg(sensor, OV5640_REG_AEC_PK_MANUAL,
- BIT(0), auto_exposure ? 0 : BIT(0));
+ ret = ov5640_set_autoexposure(sensor, auto_exp);
if (ret)
return ret;
}

- if (!auto_exposure && ctrls->exposure->is_new) {
+ if (!auto_exp && ctrls->exposure->is_new) {
u16 max_exp;

ret = ov5640_read_reg16(sensor, OV5640_REG_AEC_PK_VTS,
@@ -2174,25 +2192,19 @@ static int ov5640_set_ctrl_exposure(struct ov5640_dev *sensor, int exp)
return ret;
}

-static int ov5640_set_ctrl_gain(struct ov5640_dev *sensor, int auto_gain)
+static int ov5640_set_ctrl_gain(struct ov5640_dev *sensor, bool auto_gain)
{
struct ov5640_ctrls *ctrls = &sensor->ctrls;
int ret = 0;

if (ctrls->auto_gain->is_new) {
- ret = ov5640_mod_reg(sensor, OV5640_REG_AEC_PK_MANUAL,
- BIT(1),
- ctrls->auto_gain->val ? 0 : BIT(1));
+ ret = ov5640_set_autogain(sensor, auto_gain);
if (ret)
return ret;
}

- if (!auto_gain && ctrls->gain->is_new) {
- u16 gain = (u16)ctrls->gain->val;
-
- ret = ov5640_write_reg16(sensor, OV5640_REG_AEC_PK_REAL_GAIN,
- gain & 0x3ff);
- }
+ if (!auto_gain && ctrls->gain->is_new)
+ ret = ov5640_set_gain(sensor, ctrls->gain->val);

return ret;
}
--
2.7.4