[PATCH v2 3/4] media: ov5640: add support of DVP parallel interface

[Hugues Fruchet <hugues.fruchet@st.com>]

Add support of DVP parallel mode in addition of
existing MIPI CSI mode. The choice between two modes
and configuration is made through device tree.

Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
---
 drivers/media/i2c/ov5640.c | 101 +++++++++++++++++++++++++++++++++++++--------
 1 file changed, 83 insertions(+), 18 deletions(-)

diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
index a576d11..826b102 100644
--- a/drivers/media/i2c/ov5640.c
+++ b/drivers/media/i2c/ov5640.c
@@ -34,14 +34,20 @@
 
 #define OV5640_DEFAULT_SLAVE_ID 0x3c
 
+#define OV5640_REG_SYS_CTRL0		0x3008
 #define OV5640_REG_CHIP_ID_HIGH		0x300a
 #define OV5640_REG_CHIP_ID_LOW		0x300b
+#define OV5640_REG_IO_MIPI_CTRL00	0x300e
+#define OV5640_REG_PAD_OUTPUT_ENABLE01	0x3017
+#define OV5640_REG_PAD_OUTPUT_ENABLE02	0x3018
 #define OV5640_REG_PAD_OUTPUT00		0x3019
+#define OV5640_REG_SYSTEM_CONTROL1	0x302e
 #define OV5640_REG_SC_PLL_CTRL0		0x3034
 #define OV5640_REG_SC_PLL_CTRL1		0x3035
 #define OV5640_REG_SC_PLL_CTRL2		0x3036
 #define OV5640_REG_SC_PLL_CTRL3		0x3037
 #define OV5640_REG_SLAVE_ID		0x3100
+#define OV5640_REG_SCCB_SYS_CTRL1	0x3103
 #define OV5640_REG_SYS_ROOT_DIVIDER	0x3108
 #define OV5640_REG_AWB_R_GAIN		0x3400
 #define OV5640_REG_AWB_G_GAIN		0x3402
@@ -1006,7 +1012,65 @@ static int ov5640_get_gain(struct ov5640_dev *sensor)
 	return gain & 0x3ff;
 }
 
-static int ov5640_set_stream(struct ov5640_dev *sensor, bool on)
+static int ov5640_set_stream_dvp(struct ov5640_dev *sensor, bool on)
+{
+	int ret;
+
+	if (on) {
+		/*
+		 * reset MIPI PCLK/SERCLK divider
+		 *
+		 * SC PLL CONTRL1 0
+		 * - [3..0]:	MIPI PCLK/SERCLK divider
+		 */
+		ret = ov5640_mod_reg(sensor, OV5640_REG_SC_PLL_CTRL1, 0xF, 0);
+		if (ret)
+			return ret;
+	}
+
+	/*
+	 * powerdown MIPI TX/RX PHY & disable MIPI
+	 *
+	 * MIPI CONTROL 00
+	 * 4:	 PWDN PHY TX
+	 * 3:	 PWDN PHY RX
+	 * 2:	 MIPI enable
+	 */
+	ret = ov5640_write_reg(sensor,
+			       OV5640_REG_IO_MIPI_CTRL00, on ? 0x18 : 0);
+	if (ret)
+		return ret;
+
+	/*
+	 * enable VSYNC/HREF/PCLK DVP control lines
+	 * & D[9:6] DVP data lines
+	 *
+	 * PAD OUTPUT ENABLE 01
+	 * - 6:		VSYNC output enable
+	 * - 5:		HREF output enable
+	 * - 4:		PCLK output enable
+	 * - [3:0]:	D[9:6] output enable
+	 */
+	ret = ov5640_write_reg(sensor,
+			       OV5640_REG_PAD_OUTPUT_ENABLE01, on ? 0x7f : 0);
+	if (ret)
+		return ret;
+
+	/*
+	 * enable D[5:2] DVP data lines (D[0:1] are unused with 8 bits
+	 * parallel mode, 8 bits output are mapped on D[9:2])
+	 *
+	 * PAD OUTPUT ENABLE 02
+	 * - [7:4]:	D[5:2] output enable
+	 *		0:1 are unused with 8 bits
+	 *		parallel mode (8 bits output
+	 *		are on D[9:2])
+	 */
+	return ov5640_write_reg(sensor,
+				OV5640_REG_PAD_OUTPUT_ENABLE02, on ? 0xf0 : 0);
+}
+
+static int ov5640_set_stream_mipi(struct ov5640_dev *sensor, bool on)
 {
 	int ret;
 
@@ -1598,17 +1662,19 @@ static int ov5640_set_power(struct ov5640_dev *sensor, bool on)
 		if (ret)
 			goto power_off;
 
-		/*
-		 * start streaming briefly followed by stream off in
-		 * order to coax the clock lane into LP-11 state.
-		 */
-		ret = ov5640_set_stream(sensor, true);
-		if (ret)
-			goto power_off;
-		usleep_range(1000, 2000);
-		ret = ov5640_set_stream(sensor, false);
-		if (ret)
-			goto power_off;
+		if (sensor->ep.bus_type == V4L2_MBUS_CSI2) {
+			/*
+			 * start streaming briefly followed by stream off in
+			 * order to coax the clock lane into LP-11 state.
+			 */
+			ret = ov5640_set_stream_mipi(sensor, true);
+			if (ret)
+				goto power_off;
+			usleep_range(1000, 2000);
+			ret = ov5640_set_stream_mipi(sensor, false);
+			if (ret)
+				goto power_off;
+		}
 
 		return 0;
 	}
@@ -2185,7 +2251,11 @@ static int ov5640_s_stream(struct v4l2_subdev *sd, int enable)
 				goto out;
 		}
 
-		ret = ov5640_set_stream(sensor, enable);
+		if (sensor->ep.bus_type == V4L2_MBUS_CSI2)
+			ret = ov5640_set_stream_mipi(sensor, enable);
+		else
+			ret = ov5640_set_stream_dvp(sensor, enable);
+
 		if (!ret)
 			sensor->streaming = enable;
 	}
@@ -2270,11 +2340,6 @@ static int ov5640_probe(struct i2c_client *client,
 		return ret;
 	}
 
-	if (sensor->ep.bus_type != V4L2_MBUS_CSI2) {
-		dev_err(dev, "invalid bus type, must be MIPI CSI2\n");
-		return -EINVAL;
-	}
-
 	/* get system clock (xclk) */
 	sensor->xclk = devm_clk_get(dev, "xclk");
 	if (IS_ERR(sensor->xclk)) {
-- 
1.9.1