[PATCH v4 4/6] media: ov5693: move hw cfg functions into ov5693_hwcfg

[Tommaso Merciai <tommaso.merciai@amarulasolutions.com>]

Move hw configuration functions into ov5693_hwcfg. This is done to
separate the code that handle the hw cfg from probe in a clean way.
Add support for ACPI-based platforms that specify the clock frequency by
using the "clock-frequency" property instead of specifying a clock
provider reference

Signed-off-by: Tommaso Merciai <tommaso.merciai@amarulasolutions.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Sakari Ailus <sakari.ailus@iki.fi>
---
Changes since v2:
 - Fix commit body as suggested by Sakari, Jacopo
 - Add details to commit body as suggested by Jacopo
 - Move ov5693_check_hwcfg into ov5693_hwcfg
 - Fix xvclk_rate position as suggested by Jacopo
 - Use devm_clk_get_optional instead of devm_clk_get as suggested Jacopo

Changes since v3:
 - Fix commit body as suggested by Jacopo
 - Add reviewed-by tags, suggested by Jacopo, Krzysztof

 drivers/media/i2c/ov5693.c | 57 +++++++++++++++++++++++---------------
 1 file changed, 34 insertions(+), 23 deletions(-)

diff --git a/drivers/media/i2c/ov5693.c b/drivers/media/i2c/ov5693.c
index d2adc5513a21..3c805a5a5181 100644
--- a/drivers/media/i2c/ov5693.c
+++ b/drivers/media/i2c/ov5693.c
@@ -1339,16 +1339,48 @@ static int ov5693_get_regulators(struct ov5693_device *ov5693)
 				       ov5693->supplies);
 }
 
-static int ov5693_check_hwcfg(struct ov5693_device *ov5693)
+static int ov5693_hwcfg(struct ov5693_device *ov5693)
 {
 	struct fwnode_handle *fwnode = dev_fwnode(ov5693->dev);
 	struct v4l2_fwnode_endpoint bus_cfg = {
 		.bus_type = V4L2_MBUS_CSI2_DPHY,
 	};
 	struct fwnode_handle *endpoint;
+	u32 xvclk_rate;
 	unsigned int i;
 	int ret;
 
+	ov5693->xvclk = devm_clk_get_optional(ov5693->dev, "xvclk");
+	if (IS_ERR(ov5693->xvclk))
+		return dev_err_probe(ov5693->dev, PTR_ERR(ov5693->xvclk),
+				     "failed to get xvclk: %ld\n",
+				     PTR_ERR(ov5693->xvclk));
+
+	if (ov5693->xvclk) {
+		xvclk_rate = clk_get_rate(ov5693->xvclk);
+	} else {
+		ret = fwnode_property_read_u32(fwnode, "clock-frequency",
+					       &xvclk_rate);
+
+		if (ret) {
+			dev_err(ov5693->dev, "can't get clock frequency");
+			return ret;
+		}
+	}
+
+	if (xvclk_rate != OV5693_XVCLK_FREQ)
+		dev_warn(ov5693->dev, "Found clk freq %u, expected %u\n",
+			 xvclk_rate, OV5693_XVCLK_FREQ);
+
+	ret = ov5693_configure_gpios(ov5693);
+	if (ret)
+		return ret;
+
+	ret = ov5693_get_regulators(ov5693);
+	if (ret)
+		return dev_err_probe(ov5693->dev, ret,
+				     "Error fetching regulators\n");
+
 	endpoint = fwnode_graph_get_next_endpoint(fwnode, NULL);
 	if (!endpoint)
 		return -EPROBE_DEFER; /* Could be provided by cio2-bridge */
@@ -1390,7 +1422,6 @@ static int ov5693_check_hwcfg(struct ov5693_device *ov5693)
 static int ov5693_probe(struct i2c_client *client)
 {
 	struct ov5693_device *ov5693;
-	u32 xvclk_rate;
 	int ret = 0;
 
 	ov5693 = devm_kzalloc(&client->dev, sizeof(*ov5693), GFP_KERNEL);
@@ -1400,7 +1431,7 @@ static int ov5693_probe(struct i2c_client *client)
 	ov5693->client = client;
 	ov5693->dev = &client->dev;
 
-	ret = ov5693_check_hwcfg(ov5693);
+	ret = ov5693_hwcfg(ov5693);
 	if (ret)
 		return ret;
 
@@ -1408,26 +1439,6 @@ static int ov5693_probe(struct i2c_client *client)
 
 	v4l2_i2c_subdev_init(&ov5693->sd, client, &ov5693_ops);
 
-	ov5693->xvclk = devm_clk_get(&client->dev, "xvclk");
-	if (IS_ERR(ov5693->xvclk)) {
-		dev_err(&client->dev, "Error getting clock\n");
-		return PTR_ERR(ov5693->xvclk);
-	}
-
-	xvclk_rate = clk_get_rate(ov5693->xvclk);
-	if (xvclk_rate != OV5693_XVCLK_FREQ)
-		dev_warn(&client->dev, "Found clk freq %u, expected %u\n",
-			 xvclk_rate, OV5693_XVCLK_FREQ);
-
-	ret = ov5693_configure_gpios(ov5693);
-	if (ret)
-		return ret;
-
-	ret = ov5693_get_regulators(ov5693);
-	if (ret)
-		return dev_err_probe(&client->dev, ret,
-				     "Error fetching regulators\n");
-
 	ov5693->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 	ov5693->pad.flags = MEDIA_PAD_FL_SOURCE;
 	ov5693->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
-- 
2.25.1