diff mbox series

[v3,3/3] media: i2c: imx219: Scale the pixel rate for analog binning

Message ID 20241125-imx219_fixes-v3-3-434fc0b541c8@ideasonboard.com (mailing list archive)
State New
Headers show
Series media: i2c: imx219: Fixes for blanking and pixel rate | expand

Commit Message

Jai Luthra Nov. 25, 2024, 3:06 p.m. UTC
When the analog binning mode is used for high framerate operation,
the pixel rate is effectively doubled. Account for this when setting up
the pixel clock rate, and applying the vblank and exposure controls.

The previous logic only used analog binning for 8-bit modes, but normal
binning limits the framerate on 10-bit 480p [1]. So with this patch we
switch to using special binning (with 2x pixel rate) for all formats of
480p mode and 8-bit 1232p.

[1]: https://github.com/raspberrypi/linux/issues/5493

Co-developed-by: Naushir Patuck <naush@raspberrypi.com>
Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Co-developed-by: Vinay Varma <varmavinaym@gmail.com>
Signed-off-by: Vinay Varma <varmavinaym@gmail.com>
Signed-off-by: Jai Luthra <jai.luthra@ideasonboard.com>
---
 drivers/media/i2c/imx219.c | 120 ++++++++++++++++++++++++++++-----------------
 1 file changed, 76 insertions(+), 44 deletions(-)
diff mbox series

Patch

diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
index 970e6362d0ae3a9078daf337155e83d637bc1ca1..39b85cdee58318b080c867afd68ca33d14d3eda7 100644
--- a/drivers/media/i2c/imx219.c
+++ b/drivers/media/i2c/imx219.c
@@ -149,6 +149,12 @@ 
 #define IMX219_PIXEL_ARRAY_WIDTH	3280U
 #define IMX219_PIXEL_ARRAY_HEIGHT	2464U
 
+enum binning_mode {
+	BINNING_NONE = IMX219_BINNING_NONE,
+	BINNING_X2 = IMX219_BINNING_X2,
+	BINNING_ANALOG_X2 = IMX219_BINNING_X2_ANALOG,
+};
+
 /* Mode : resolution and related config&values */
 struct imx219_mode {
 	/* Frame width */
@@ -337,6 +343,10 @@  struct imx219 {
 
 	/* Two or Four lanes */
 	u8 lanes;
+
+	/* Binning mode */
+	enum binning_mode bin_h;
+	enum binning_mode bin_v;
 };
 
 static inline struct imx219 *to_imx219(struct v4l2_subdev *_sd)
@@ -362,6 +372,36 @@  static u32 imx219_get_format_code(struct imx219 *imx219, u32 code)
 	return imx219_mbus_formats[i];
 }
 
+static u32 imx219_get_format_bpp(const struct v4l2_mbus_framefmt *format)
+{
+	switch (format->code) {
+	case MEDIA_BUS_FMT_SRGGB8_1X8:
+	case MEDIA_BUS_FMT_SGRBG8_1X8:
+	case MEDIA_BUS_FMT_SGBRG8_1X8:
+	case MEDIA_BUS_FMT_SBGGR8_1X8:
+		return 8;
+
+	case MEDIA_BUS_FMT_SRGGB10_1X10:
+	case MEDIA_BUS_FMT_SGRBG10_1X10:
+	case MEDIA_BUS_FMT_SGBRG10_1X10:
+	case MEDIA_BUS_FMT_SBGGR10_1X10:
+	default:
+		return 10;
+	}
+}
+
+static int imx219_get_rate_factor(struct imx219 *imx219)
+{
+	switch (imx219->bin_v) {
+	case BINNING_NONE:
+	case BINNING_X2:
+		return 1;
+	case BINNING_ANALOG_X2:
+		return 2;
+	}
+	return -EINVAL;
+}
+
 /* -----------------------------------------------------------------------------
  * Controls
  */
@@ -373,10 +413,12 @@  static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
 	struct i2c_client *client = v4l2_get_subdevdata(&imx219->sd);
 	const struct v4l2_mbus_framefmt *format;
 	struct v4l2_subdev_state *state;
+	int rate_factor;
 	int ret = 0;
 
 	state = v4l2_subdev_get_locked_active_state(&imx219->sd);
 	format = v4l2_subdev_state_get_format(state, 0);
+	rate_factor = imx219_get_rate_factor(imx219);
 
 	if (ctrl->id == V4L2_CID_VBLANK) {
 		int exposure_max, exposure_def;
@@ -405,7 +447,7 @@  static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	case V4L2_CID_EXPOSURE:
 		cci_write(imx219->regmap, IMX219_REG_EXPOSURE,
-			  ctrl->val, &ret);
+			  ctrl->val / rate_factor, &ret);
 		break;
 	case V4L2_CID_DIGITAL_GAIN:
 		cci_write(imx219->regmap, IMX219_REG_DIGITAL_GAIN,
@@ -422,7 +464,7 @@  static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 	case V4L2_CID_VBLANK:
 		cci_write(imx219->regmap, IMX219_REG_VTS,
-			  format->height + ctrl->val, &ret);
+			  (format->height + ctrl->val) / rate_factor, &ret);
 		break;
 	case V4L2_CID_HBLANK:
 		cci_write(imx219->regmap, IMX219_REG_HTS,
@@ -463,7 +505,8 @@  static const struct v4l2_ctrl_ops imx219_ctrl_ops = {
 
 static unsigned long imx219_get_pixel_rate(struct imx219 *imx219)
 {
-	return (imx219->lanes == 2) ? IMX219_PIXEL_RATE : IMX219_PIXEL_RATE_4LANE;
+	return ((imx219->lanes == 2) ? IMX219_PIXEL_RATE :
+		IMX219_PIXEL_RATE_4LANE) * imx219_get_rate_factor(imx219);
 }
 
 /* Initialize control handlers */
@@ -592,29 +635,12 @@  static int imx219_set_framefmt(struct imx219 *imx219,
 {
 	const struct v4l2_mbus_framefmt *format;
 	const struct v4l2_rect *crop;
-	unsigned int bpp;
-	u64 bin_h, bin_v;
+	u32 bpp;
 	int ret = 0;
 
 	format = v4l2_subdev_state_get_format(state, 0);
 	crop = v4l2_subdev_state_get_crop(state, 0);
-
-	switch (format->code) {
-	case MEDIA_BUS_FMT_SRGGB8_1X8:
-	case MEDIA_BUS_FMT_SGRBG8_1X8:
-	case MEDIA_BUS_FMT_SGBRG8_1X8:
-	case MEDIA_BUS_FMT_SBGGR8_1X8:
-		bpp = 8;
-		break;
-
-	case MEDIA_BUS_FMT_SRGGB10_1X10:
-	case MEDIA_BUS_FMT_SGRBG10_1X10:
-	case MEDIA_BUS_FMT_SGBRG10_1X10:
-	case MEDIA_BUS_FMT_SBGGR10_1X10:
-	default:
-		bpp = 10;
-		break;
-	}
+	bpp = imx219_get_format_bpp(format);
 
 	cci_write(imx219->regmap, IMX219_REG_X_ADD_STA_A,
 		  crop->left - IMX219_PIXEL_ARRAY_LEFT, &ret);
@@ -625,28 +651,8 @@  static int imx219_set_framefmt(struct imx219 *imx219,
 	cci_write(imx219->regmap, IMX219_REG_Y_ADD_END_A,
 		  crop->top - IMX219_PIXEL_ARRAY_TOP + crop->height - 1, &ret);
 
-	switch (crop->width / format->width) {
-	case 1:
-	default:
-		bin_h = IMX219_BINNING_NONE;
-		break;
-	case 2:
-		bin_h = bpp == 8 ? IMX219_BINNING_X2_ANALOG : IMX219_BINNING_X2;
-		break;
-	}
-
-	switch (crop->height / format->height) {
-	case 1:
-	default:
-		bin_v = IMX219_BINNING_NONE;
-		break;
-	case 2:
-		bin_v = bpp == 8 ? IMX219_BINNING_X2_ANALOG : IMX219_BINNING_X2;
-		break;
-	}
-
-	cci_write(imx219->regmap, IMX219_REG_BINNING_MODE_H, bin_h, &ret);
-	cci_write(imx219->regmap, IMX219_REG_BINNING_MODE_V, bin_v, &ret);
+	cci_write(imx219->regmap, IMX219_REG_BINNING_MODE_H, imx219->bin_h, &ret);
+	cci_write(imx219->regmap, IMX219_REG_BINNING_MODE_V, imx219->bin_v, &ret);
 
 	cci_write(imx219->regmap, IMX219_REG_X_OUTPUT_SIZE,
 		  format->width, &ret);
@@ -851,6 +857,27 @@  static int imx219_set_pad_format(struct v4l2_subdev *sd,
 		int exposure_max;
 		int exposure_def;
 		int hblank;
+		int pixel_rate;
+		u32 bpp = imx219_get_format_bpp(format);
+		enum binning_mode binning = BINNING_NONE;
+
+		/*
+		 * For 8-bit formats, analog horizontal binning is required,
+		 * else the output image is garbage.
+		 * For 10-bit formats, analog horizontal binning is optional,
+		 * but still useful as it doubles the effective framerate.
+		 * We can only use it with width <= 1624, as for higher values
+		 * there are blocky artefacts.
+		 *
+		 * Vertical binning should match the horizontal binning mode.
+		 */
+		if (bin_h == 2 && (format->width <= 1624 || bpp == 8))
+			binning = BINNING_ANALOG_X2;
+		else
+			binning = BINNING_X2;
+
+		imx219->bin_h = (bin_h == 2) ? binning : BINNING_NONE;
+		imx219->bin_v = (bin_v == 2) ? binning : BINNING_NONE;
 
 		/* Update limits and set FPS to default */
 		__v4l2_ctrl_modify_range(imx219->vblank, IMX219_VBLANK_MIN,
@@ -879,6 +906,11 @@  static int imx219_set_pad_format(struct v4l2_subdev *sd,
 					 IMX219_PPL_MAX - mode->width,
 					 1, IMX219_PPL_MIN - mode->width);
 		__v4l2_ctrl_s_ctrl(imx219->hblank, hblank);
+
+		/* Scale the pixel rate based on the mode specific factor */
+		pixel_rate = imx219_get_pixel_rate(imx219);
+		__v4l2_ctrl_modify_range(imx219->pixel_rate, pixel_rate,
+					 pixel_rate, 1, pixel_rate);
 	}
 
 	return 0;