[PATCH 12/21] media: i2c: imx258: Allow configuration of clock lane behaviour

[Dave Stevenson <dave.stevenson@raspberrypi.com>]

The sensor supports the clock lane either remaining in HS mode
during frame blanking, or dropping to LP11.

Add configuration of the mode via V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/media/i2c/imx258.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c
index 1fa83fe82f27..b5c2dcb7c9e6 100644
--- a/drivers/media/i2c/imx258.c
+++ b/drivers/media/i2c/imx258.c
@@ -72,6 +72,8 @@
 /* Test Pattern Control */
 #define IMX258_REG_TEST_PATTERN		0x0600
 
+#define IMX258_CLK_BLANK_STOP		0x4040
+
 /* Orientation */
 #define REG_MIRROR_FLIP_CONTROL		0x0101
 #define REG_CONFIG_MIRROR_FLIP		0x03
@@ -634,6 +636,7 @@ struct imx258 {
 	const struct imx258_link_freq_config *link_freq_configs;
 	const s64 *link_freq_menu_items;
 	unsigned int nlanes;
+	unsigned int csi2_flags;
 
 	/*
 	 * Mutex for serialized access:
@@ -1072,6 +1075,15 @@ static int imx258_start_streaming(struct imx258 *imx258)
 		return ret;
 	}
 
+	ret = imx258_write_reg(imx258, IMX258_CLK_BLANK_STOP,
+			       IMX258_REG_VALUE_08BIT,
+			       imx258->csi2_flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK ?
+			       1 : 0);
+	if (ret) {
+		dev_err(&client->dev, "%s failed to set clock lane mode\n", __func__);
+		return ret;
+	}
+
 	/* Apply default values of current mode */
 	reg_list = &imx258->cur_mode->reg_list;
 	ret = imx258_write_regs(imx258, reg_list->regs, reg_list->num_of_regs);
@@ -1486,6 +1498,8 @@ static int imx258_probe(struct i2c_client *client)
 		goto error_endpoint_poweron;
 	}
 
+	imx258->csi2_flags = ep.bus.mipi_csi2.flags;
+
 	/* Initialize subdev */
 	v4l2_i2c_subdev_init(&imx258->sd, client, &imx258_subdev_ops);
 
-- 
2.25.1