media: i2c: ov5645: Fix power sequence

This is mostly a port of Jacopo's fix:

  commit aa4bb8b8
  Author: Jacopo Mondi <jacopo@jmondi.org>
  Date:   Fri Jul 6 05:51:52 2018 -0400

  media: ov5640: Re-work MIPI startup sequence

In the OV5645 case, the changes are:

- At set_power(1) time power up MIPI Tx/Rx and set data and clock lanes in
  LP11 during 'sleep' and 'idle' with MIPI clock in non-continuous mode.
- At set_power(0) time power down MIPI Tx/Rx (in addition to the current
  power down of regulators and clock gating).
- At s_stream time enable/disable the MIPI interface output.

With this commit the sensor is able to enter LP-11 mode during power up,
as expected by some CSI-2 controllers.

Many thanks to Fabio Estevam for his help debugging this issue.
Tested-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/i2c/ov5645.c

@@ -41,6 +41,8 @@
 #define		OV5645_CHIP_ID_HIGH_BYTE	0x56
 #define OV5645_CHIP_ID_LOW		0x300b
 #define		OV5645_CHIP_ID_LOW_BYTE		0x45
+#define OV5645_IO_MIPI_CTRL00		0x300e
+#define OV5645_PAD_OUTPUT00		0x3019
 #define OV5645_AWB_MANUAL_CONTROL	0x3406
 #define		OV5645_AWB_MANUAL_ENABLE	BIT(0)
 #define OV5645_AEC_PK_MANUAL		0x3503
@@ -51,6 +53,7 @@
 #define		OV5645_ISP_VFLIP		BIT(2)
 #define OV5645_TIMING_TC_REG21		0x3821
 #define		OV5645_SENSOR_MIRROR		BIT(1)
+#define OV5645_MIPI_CTRL00		0x4800
 #define OV5645_PRE_ISP_TEST_SETTING_1	0x503d
 #define		OV5645_TEST_PATTERN_MASK	0x3
 #define		OV5645_SET_TEST_PATTERN(x)	((x) & OV5645_TEST_PATTERN_MASK)
@@ -124,7 +127,6 @@ static const struct reg_value ov5645_global_init_setting[] = {
 	{ 0x3503, 0x07 },
 	{ 0x3002, 0x1c },
 	{ 0x3006, 0xc3 },
-	{ 0x300e, 0x45 },
 	{ 0x3017, 0x00 },
 	{ 0x3018, 0x00 },
 	{ 0x302e, 0x0b },
@@ -353,7 +355,10 @@ static const struct reg_value ov5645_global_init_setting[] = {
 	{ 0x3a1f, 0x14 },
 	{ 0x0601, 0x02 },
 	{ 0x3008, 0x42 },
-	{ 0x3008, 0x02 }
+	{ 0x3008, 0x02 },
+	{ OV5645_IO_MIPI_CTRL00, 0x40 },
+	{ OV5645_MIPI_CTRL00, 0x24 },
+	{ OV5645_PAD_OUTPUT00, 0x70 }
 };
 
 static const struct reg_value ov5645_setting_sxga[] = {
@@ -690,13 +695,9 @@ static int ov5645_s_power(struct v4l2_subdev *sd, int on)
 				goto exit;
 			}
 
-			ret = ov5645_write_reg(ov5645, OV5645_SYSTEM_CTRL0,
-					       OV5645_SYSTEM_CTRL0_STOP);
-			if (ret < 0) {
-				ov5645_set_power_off(ov5645);
-				goto exit;
-			}
+			usleep_range(500, 1000);
 		} else {
+			ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x58);
 			ov5645_set_power_off(ov5645);
 		}
 	}
@@ -1002,11 +1003,20 @@ static int ov5645_s_stream(struct v4l2_subdev *subdev, int enable)
 			dev_err(ov5645->dev, "could not sync v4l2 controls\n");
 			return ret;
 		}
+
+		ret = ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x45);
+		if (ret < 0)
+			return ret;
+
 		ret = ov5645_write_reg(ov5645, OV5645_SYSTEM_CTRL0,
 				       OV5645_SYSTEM_CTRL0_START);
 		if (ret < 0)
 			return ret;
 	} else {
+		ret = ov5645_write_reg(ov5645, OV5645_IO_MIPI_CTRL00, 0x40);
+		if (ret < 0)
+			return ret;
+
 		ret = ov5645_write_reg(ov5645, OV5645_SYSTEM_CTRL0,
 				       OV5645_SYSTEM_CTRL0_STOP);
 		if (ret < 0)