From 3143b459de4cdcce67b36827476c966e93c1cf01 Mon Sep 17 00:00:00 2001
From: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Date: Tue, 3 Sep 2019 17:11:43 -0300
Subject: [PATCH] media: ov6650: Fix stored frame format not in sync with hardware
Git-commit: 3143b459de4cdcce67b36827476c966e93c1cf01
Patch-mainline: v5.5-rc1
References: bsc#1051510

The driver stores frame format settings supposed to be in line with
hardware state in a device private structure.  Since the driver initial
submission, those settings are updated before they are actually applied
on hardware.  If an error occurs on device update, the stored settings
my not reflect hardware state anymore and consecutive calls to
.get_fmt() may return incorrect information.  That in turn may affect
ability of a bridge device to use correct DMA transfer settings if such
incorrect informmation on active frame format returned by .get_fmt() is
used.

Assuming a failed device update means its state hasn't changed, update
frame format related settings stored in the device private structure
only after they are successfully applied so the stored values always
reflect hardware state as closely as possible.

Fixes: 2f6e2404799a ("[media] SoC Camera: add driver for OV6650 sensor")
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/media/i2c/soc_camera/ov6650.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/media/i2c/soc_camera/ov6650.c
+++ b/drivers/media/i2c/soc_camera/ov6650.c
@@ -628,7 +628,6 @@ static int ov6650_s_fmt(struct v4l2_subd
 		dev_err(&client->dev, "Pixel format not handled: 0x%x\n", code);
 		return -EINVAL;
 	}
-	priv->code = code;
 
 	if (code == MEDIA_BUS_FMT_Y8_1X8 ||
 			code == MEDIA_BUS_FMT_SBGGR8_1X8) {
@@ -649,7 +648,6 @@ static int ov6650_s_fmt(struct v4l2_subd
 		dev_dbg(&client->dev, "max resolution: CIF\n");
 		coma_mask |= COMA_QCIF;
 	}
-	priv->half_scale = half_scale;
 
 	if (sense) {
 		if (sense->master_clock == 8000000) {
@@ -689,8 +687,13 @@ static int ov6650_s_fmt(struct v4l2_subd
 		ret = ov6650_reg_rmw(client, REG_COMA, coma_set, coma_mask);
 	if (!ret)
 		ret = ov6650_reg_write(client, REG_CLKRC, clkrc);
-	if (!ret)
+	if (!ret) {
+		priv->half_scale = half_scale;
+
 		ret = ov6650_reg_rmw(client, REG_COML, coml_set, coml_mask);
+	}
+	if (!ret)
+		priv->code = code;
 
 	return ret;
 }