[media] mt9v022: set y_skip_top field to zero as default

Set "y_skip_top" to zero and revise comment as I do not see this line
corruption on two different mt9v022 setups. The first read-out line
is perfectly fine. Add mt9v022 platform data configuring y_skip_top
for platforms that have issues with the first read-out line. Set
y_skip_top to 1 for pcm990 board.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

arch/arm/mach-pxa/pcm990-baseboard.c

@@ -26,6 +26,7 @@
 #include <linux/i2c/pxa-i2c.h>
 #include <linux/pwm_backlight.h>
 
+#include <media/mt9v022.h>
 #include <media/soc_camera.h>
 
 #include <linux/platform_data/camera-pxa.h>
@@ -468,6 +469,10 @@ static struct i2c_board_info __initdata pcm990_i2c_devices[] = {
 	},
 };
 
+static struct mt9v022_platform_data mt9v022_pdata = {
+	.y_skip_top = 1,
+};
+
 static struct i2c_board_info pcm990_camera_i2c[] = {
 	{
 		I2C_BOARD_INFO("mt9v022", 0x48),
@@ -480,6 +485,7 @@ static struct soc_camera_link iclink[] = {
 	{
 		.bus_id			= 0, /* Must match with the camera ID */
 		.board_info		= &pcm990_camera_i2c[0],
+		.priv			= &mt9v022_pdata,
 		.i2c_adapter_id		= 0,
 		.query_bus_param	= pcm990_camera_query_bus_param,
 		.set_bus_param		= pcm990_camera_set_bus_param,

drivers/media/i2c/soc_camera/mt9v022.c

@@ -15,6 +15,7 @@
 #include <linux/log2.h>
 #include <linux/module.h>
 
+#include <media/mt9v022.h>
 #include <media/soc_camera.h>
 #include <media/soc_mediabus.h>
 #include <media/v4l2-subdev.h>
@@ -869,6 +870,7 @@ static int mt9v022_probe(struct i2c_client *client,
 	struct mt9v022 *mt9v022;
 	struct soc_camera_link *icl = soc_camera_i2c_to_link(client);
 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+	struct mt9v022_platform_data *pdata = icl->priv;
 	int ret;
 
 	if (!icl) {
@@ -932,10 +934,10 @@ static int mt9v022_probe(struct i2c_client *client,
 	mt9v022->chip_control = MT9V022_CHIP_CONTROL_DEFAULT;
 
 	/*
-	 * MT9V022 _really_ corrupts the first read out line.
-	 * TODO: verify on i.MX31
+	 * On some platforms the first read out line is corrupted.
+	 * Workaround it by skipping if indicated by platform data.
 	 */
-	mt9v022->y_skip_top	= 1;
+	mt9v022->y_skip_top	= pdata ? pdata->y_skip_top : 0;
 	mt9v022->rect.left	= MT9V022_COLUMN_SKIP;
 	mt9v022->rect.top	= MT9V022_ROW_SKIP;
 	mt9v022->rect.width	= MT9V022_MAX_WIDTH;

include/media/mt9v022.h

@@ -0,0 +1,16 @@
+/*
+ * mt9v022 sensor
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __MT9V022_H__
+#define __MT9V022_H__
+
+struct mt9v022_platform_data {
+	unsigned short y_skip_top;	/* Lines to skip at the top */
+};
+
+#endif