From 6b0cce78e4c84189c93ad0fbad7b8d08439135d4 Mon Sep 17 00:00:00 2001
From: Naushir Patuck <naush@raspberrypi.com>
Date: Tue, 14 Mar 2023 12:56:14 +0000
Subject: [PATCH] media: i2c: imx296: Add helper for hblank control
Add a helper function to setup the horizontal blanking control. Update
the control limits on set_format as the horizontal blanking time must
remain constant regardless of sensor output width.
Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
---
drivers/media/i2c/imx296.c | 44 ++++++++++++++++++++++++++------------
1 file changed, 30 insertions(+), 14 deletions(-)
--- a/drivers/media/i2c/imx296.c
+++ b/drivers/media/i2c/imx296.c
@@ -384,10 +384,36 @@ static const struct v4l2_ctrl_ops imx296
.s_ctrl = imx296_s_ctrl,
};
+static void imx296_setup_hblank(struct imx296 *sensor, unsigned int width)
+{
+ /*
+ * Horizontal blanking is controlled through the HMAX register, which
+ * contains a line length in contains a line length in units of an
+ * internal 74.25 MHz clock derived from the INCLK. The HMAX value is
+ * currently fixed to 1100, convert it to a number of pixels based on
+ * the nominal pixel rate.
+ *
+ * Horizontal blanking is fixed, regardless of the crop width, so
+ * ensure the hblank limits are adjusted to account for this.
+ */
+ unsigned int hblank = 1100 * 1188000000ULL / 10 / 74250000 - width;
+
+ if (!sensor->hblank) {
+ sensor->hblank = v4l2_ctrl_new_std(&sensor->ctrls,
+ &imx296_ctrl_ops,
+ V4L2_CID_HBLANK, hblank,
+ hblank, 1, hblank);
+ if (sensor->hblank)
+ sensor->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+ } else {
+ __v4l2_ctrl_modify_range(sensor->hblank, hblank, hblank, 1,
+ hblank);
+ }
+}
+
static int imx296_ctrls_init(struct imx296 *sensor)
{
struct v4l2_fwnode_device_properties props;
- unsigned int hblank;
int ret;
ret = v4l2_fwnode_device_parse(sensor->dev, &props);
@@ -402,19 +428,7 @@ static int imx296_ctrls_init(struct imx2
V4L2_CID_ANALOGUE_GAIN, IMX296_GAIN_MIN,
IMX296_GAIN_MAX, 1, IMX296_GAIN_MIN);
- /*
- * Horizontal blanking is controlled through the HMAX register, which
- * contains a line length in INCK clock units. The INCK frequency is
- * fixed to 74.25 MHz. The HMAX value is currently fixed to 1100,
- * convert it to a number of pixels based on the nominal pixel rate.
- */
- hblank = 1100 * 1188000000ULL / 10 / 74250000
- - IMX296_PIXEL_ARRAY_WIDTH;
- sensor->hblank = v4l2_ctrl_new_std(&sensor->ctrls, &imx296_ctrl_ops,
- V4L2_CID_HBLANK, hblank, hblank, 1,
- hblank);
- if (sensor->hblank)
- sensor->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+ imx296_setup_hblank(sensor, IMX296_PIXEL_ARRAY_WIDTH);
sensor->vblank = v4l2_ctrl_new_std(&sensor->ctrls, &imx296_ctrl_ops,
V4L2_CID_VBLANK, 30,
@@ -739,6 +753,8 @@ static int imx296_set_format(struct v4l2
format->height = crop->height;
}
+ imx296_setup_hblank(sensor, format->width);
+
format->code = sensor->mono ? MEDIA_BUS_FMT_Y10_1X10
: MEDIA_BUS_FMT_SBGGR10_1X10;
format->field = V4L2_FIELD_NONE;