[PATCH 5/5] media: i2c: imx290: Add configurable link frequency and pixel rate

[Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>]

IMX290 operates with multiple link frequency and pixel rate combinations.
The initial driver used a single setting for both but since we now have
the lane count support in place, let's add configurable link frequency
and pixel rate.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/media/i2c/imx290.c | 155 +++++++++++++++++++++----------------
 1 file changed, 89 insertions(+), 66 deletions(-)

diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
index f26c4a0ee0a0..d794ade26609 100644
--- a/drivers/media/i2c/imx290.c
+++ b/drivers/media/i2c/imx290.c
@@ -45,8 +45,6 @@
 #define IMX290_HMAX_2_720 0x19C8
 #define IMX290_HMAX_4_720 0x0CE4
 
-#define IMX290_DEFAULT_LINK_FREQ 445500000
-
 static const char * const imx290_supply_name[] = {
 	"vdda",
 	"vddd",
@@ -63,8 +61,6 @@ struct imx290_regval {
 struct imx290_mode {
 	u32 width;
 	u32 height;
-	u32 pixel_rate;
-	u32 link_freq_index;
 
 	const struct imx290_regval *data;
 	u32 data_size;
@@ -281,7 +277,10 @@ static const struct imx290_regval imx290_12bit_settings[] = {
 
 /* supported link frequencies */
 static const s64 imx290_link_freq[] = {
-	IMX290_DEFAULT_LINK_FREQ,
+	891000000, /* 1920x1080 -  2 lane */
+	445500000, /* 1920x1080 -  4 lane */
+	594000000, /* 1280x720  -  2 lane */
+	297000000, /* 1280x720  -  4 lane */
 };
 
 /* Mode configs */
@@ -291,16 +290,12 @@ static const struct imx290_mode imx290_modes[] = {
 		.height = 1080,
 		.data = imx290_1080p_settings,
 		.data_size = ARRAY_SIZE(imx290_1080p_settings),
-		.pixel_rate = 178200000,
-		.link_freq_index = 0,
 	},
 	{
 		.width = 1280,
 		.height = 720,
 		.data = imx290_720p_settings,
 		.data_size = ARRAY_SIZE(imx290_720p_settings),
-		.pixel_rate = 178200000,
-		.link_freq_index = 0,
 	},
 };
 
@@ -509,6 +504,73 @@ static int imx290_get_fmt(struct v4l2_subdev *sd,
 	return 0;
 }
 
+static s64 imx290_get_link_freq_index(struct imx290 *imx290)
+{
+	const struct imx290_mode *cur_mode = imx290->current_mode;
+	u8 index;
+
+	if (cur_mode->width == 1920)
+		index = imx290->nlanes / 4;
+	else
+		index = (imx290->nlanes / 4) + 2;
+
+	return index;
+}
+
+static s64 imx290_get_link_freq(struct imx290 *imx290)
+{
+	u8 index = imx290_get_link_freq_index(imx290);
+
+	return imx290_link_freq[index];
+}
+
+static u64 imx290_calc_pixel_rate(struct imx290 *imx290)
+{
+	s64 link_freq = imx290_get_link_freq(imx290);
+	u8 nlanes = imx290->nlanes;
+
+	/* pixel rate = link_freq * 2 * nr_of_lanes / bits_per_sample */
+	return (link_freq * 2 * nlanes / imx290->bpp);
+}
+
+static int imx290_write_current_format(struct imx290 *imx290,
+				       struct v4l2_mbus_framefmt *format)
+{
+	int ret;
+
+	switch (format->code) {
+	case MEDIA_BUS_FMT_SRGGB10_1X10:
+		ret = imx290_set_register_array(imx290, imx290_10bit_settings,
+						ARRAY_SIZE(
+							imx290_10bit_settings));
+		if (ret < 0) {
+			dev_err(imx290->dev, "Could not set format registers\n");
+			return ret;
+		}
+
+		imx290->bpp = 10;
+
+		break;
+	case MEDIA_BUS_FMT_SRGGB12_1X12:
+		ret = imx290_set_register_array(imx290, imx290_12bit_settings,
+						ARRAY_SIZE(
+							imx290_12bit_settings));
+		if (ret < 0) {
+			dev_err(imx290->dev, "Could not set format registers\n");
+			return ret;
+		}
+
+		imx290->bpp = 12;
+
+		break;
+	default:
+		dev_err(imx290->dev, "Unknown pixel format\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int imx290_set_fmt(struct v4l2_subdev *sd,
 			  struct v4l2_subdev_pad_config *cfg,
 		      struct v4l2_subdev_format *fmt)
@@ -517,6 +579,7 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
 	const struct imx290_mode *mode;
 	struct v4l2_mbus_framefmt *format;
 	unsigned int i;
+	int ret = 0;
 
 	mutex_lock(&imx290->lock);
 
@@ -542,17 +605,27 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
 		format = v4l2_subdev_get_try_format(sd, cfg, fmt->pad);
 	} else {
 		format = &imx290->current_format;
-		__v4l2_ctrl_s_ctrl(imx290->link_freq, mode->link_freq_index);
-		__v4l2_ctrl_s_ctrl_int64(imx290->pixel_rate, mode->pixel_rate);
-
 		imx290->current_mode = mode;
+
+		/* Set current frame format */
+		ret = imx290_write_current_format(imx290, &fmt->format);
+		if (ret < 0) {
+			dev_err(imx290->dev, "Could not set frame format\n");
+			goto err_out;
+		}
+
+		__v4l2_ctrl_s_ctrl(imx290->link_freq,
+				   imx290_get_link_freq_index(imx290));
+		__v4l2_ctrl_s_ctrl_int64(imx290->pixel_rate,
+					 imx290_calc_pixel_rate(imx290));
 	}
 
 	*format = fmt->format;
 
+err_out:
 	mutex_unlock(&imx290->lock);
 
-	return 0;
+	return ret;
 }
 
 static int imx290_entity_init_cfg(struct v4l2_subdev *subdev,
@@ -569,44 +642,6 @@ static int imx290_entity_init_cfg(struct v4l2_subdev *subdev,
 	return 0;
 }
 
-static int imx290_write_current_format(struct imx290 *imx290,
-				       struct v4l2_mbus_framefmt *format)
-{
-	int ret;
-
-	switch (format->code) {
-	case MEDIA_BUS_FMT_SRGGB10_1X10:
-		ret = imx290_set_register_array(imx290, imx290_10bit_settings,
-						ARRAY_SIZE(
-							imx290_10bit_settings));
-		if (ret < 0) {
-			dev_err(imx290->dev, "Could not set format registers\n");
-			return ret;
-		}
-
-		imx290->bpp = 10;
-
-		break;
-	case MEDIA_BUS_FMT_SRGGB12_1X12:
-		ret = imx290_set_register_array(imx290, imx290_12bit_settings,
-						ARRAY_SIZE(
-							imx290_12bit_settings));
-		if (ret < 0) {
-			dev_err(imx290->dev, "Could not set format registers\n");
-			return ret;
-		}
-
-		imx290->bpp = 12;
-
-		break;
-	default:
-		dev_err(imx290->dev, "Unknown pixel format\n");
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
 static int imx290_set_hmax(struct imx290 *imx290, u32 val)
 {
 	int ret;
@@ -640,13 +675,6 @@ static int imx290_start_streaming(struct imx290 *imx290)
 		return ret;
 	}
 
-	/* Set current frame format */
-	ret = imx290_write_current_format(imx290, &imx290->current_format);
-	if (ret < 0) {
-		dev_err(imx290->dev, "Could not set frame format\n");
-		return ret;
-	}
-
 	/* Apply default values of current mode */
 	ret = imx290_set_register_array(imx290, imx290->current_mode->data,
 					imx290->current_mode->data_size);
@@ -901,12 +929,6 @@ static int imx290_probe(struct i2c_client *client)
 		goto free_err;
 	}
 
-	if (imx290->ep.link_frequencies[0] != IMX290_DEFAULT_LINK_FREQ) {
-		dev_err(dev, "Unsupported link frequency\n");
-		ret = -EINVAL;
-		goto free_err;
-	}
-
 	/* Only CSI2 is supported for now */
 	if (imx290->ep.bus_type != V4L2_MBUS_CSI2_DPHY) {
 		dev_err(dev, "Unsupported bus type, should be CSI2\n");
@@ -973,14 +995,15 @@ static int imx290_probe(struct i2c_client *client)
 				       &imx290_ctrl_ops,
 				       V4L2_CID_LINK_FREQ,
 				       ARRAY_SIZE(imx290_link_freq) - 1,
-				       0, imx290_link_freq);
+				       (imx290->nlanes / 4),
+				       imx290_link_freq);
 	if (imx290->link_freq)
 		imx290->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
 
 	imx290->pixel_rate = v4l2_ctrl_new_std(&imx290->ctrls, &imx290_ctrl_ops,
 					       V4L2_CID_PIXEL_RATE, 1,
 					       INT_MAX, 1,
-					       imx290_modes[0].pixel_rate);
+					       imx290_calc_pixel_rate(imx290));
 
 	v4l2_ctrl_new_std_menu_items(&imx290->ctrls, &imx290_ctrl_ops,
 				     V4L2_CID_TEST_PATTERN,
-- 
2.17.1