From df60764ea52102f433b76cfa4fc873229e60e76c Mon Sep 17 00:00:00 2001 From: Richard Leitner Date: Tue, 9 Dec 2025 23:44:43 +0100 Subject: [PATCH] media: i2c: ov9282: dynamic flash_duration maximum This patch sets the current exposure time as maximum for the flash_duration control. As Flash/Strobes which are longer than the exposure time have no effect. Signed-off-by: Richard Leitner [Sakari Ailus: Some lines rewrapped.] Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil --- drivers/media/i2c/ov9282.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c index 3c74d65fe3125..ded9b2044ff8f 100644 --- a/drivers/media/i2c/ov9282.c +++ b/drivers/media/i2c/ov9282.c @@ -199,6 +199,7 @@ struct ov9282_mode { * @exp_ctrl: Pointer to exposure control * @again_ctrl: Pointer to analog gain control * @pixel_rate: Pointer to pixel rate control + * @flash_duration: Pointer to flash duration control * @vblank: Vertical blanking in lines * @noncontinuous_clock: Selection of CSI2 noncontinuous clock mode * @cur_mode: Pointer to current selected sensor mode @@ -221,6 +222,7 @@ struct ov9282 { struct v4l2_ctrl *again_ctrl; }; struct v4l2_ctrl *pixel_rate; + struct v4l2_ctrl *flash_duration; u32 vblank; bool noncontinuous_clock; const struct ov9282_mode *cur_mode; @@ -612,6 +614,15 @@ static int ov9282_update_controls(struct ov9282 *ov9282, mode->vblank_max, 1, mode->vblank); } +static u32 ov9282_exposure_to_us(struct ov9282 *ov9282, u32 exposure) +{ + /* calculate exposure time in µs */ + u32 frame_width = ov9282->cur_mode->width + ov9282->hblank_ctrl->val; + u32 trow_us = frame_width / (ov9282->pixel_rate->val / 1000000UL); + + return exposure * trow_us; +} + /** * ov9282_update_exp_gain() - Set updated exposure and gain * @ov9282: pointer to ov9282 device @@ -623,9 +634,10 @@ static int ov9282_update_controls(struct ov9282 *ov9282, static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain) { int ret; + u32 exposure_us = ov9282_exposure_to_us(ov9282, exposure); - dev_dbg(ov9282->dev, "Set exp %u, analog gain %u", - exposure, gain); + dev_dbg(ov9282->dev, "Set exp %u (~%u us), analog gain %u", + exposure, exposure_us, gain); ret = ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 1); if (ret) @@ -636,6 +648,12 @@ static int ov9282_update_exp_gain(struct ov9282 *ov9282, u32 exposure, u32 gain) goto error_release_group_hold; ret = ov9282_write_reg(ov9282, OV9282_REG_AGAIN, 1, gain); + if (ret) + goto error_release_group_hold; + + ret = __v4l2_ctrl_modify_range(ov9282->flash_duration, + 0, exposure_us, 1, + OV9282_STROBE_FRAME_SPAN_DEFAULT); error_release_group_hold: ov9282_write_reg(ov9282, OV9282_REG_HOLD, 1, 0); @@ -1431,6 +1449,7 @@ static int ov9282_init_controls(struct ov9282 *ov9282) const struct ov9282_mode *mode = ov9282->cur_mode; struct v4l2_fwnode_device_properties props; u32 hblank_min; + u32 exposure_us; u32 lpfr; int ret; @@ -1503,8 +1522,11 @@ static int ov9282_init_controls(struct ov9282 *ov9282) v4l2_ctrl_new_std(ctrl_hdlr, &ov9282_ctrl_ops, V4L2_CID_FLASH_STROBE_OE, 0, 1, 1, 0); - v4l2_ctrl_new_std(ctrl_hdlr, &ov9282_ctrl_ops, V4L2_CID_FLASH_DURATION, - 0, 13900, 1, 8); + exposure_us = ov9282_exposure_to_us(ov9282, OV9282_EXPOSURE_DEFAULT); + ov9282->flash_duration = + v4l2_ctrl_new_std(ctrl_hdlr, &ov9282_ctrl_ops, + V4L2_CID_FLASH_DURATION, 0, exposure_us, 1, + OV9282_STROBE_FRAME_SPAN_DEFAULT); ret = v4l2_fwnode_device_parse(ov9282->dev, &props); if (!ret) { -- 2.47.3