[PATCH v4 2/5] media: i2c: lm3560: Fix v4l2 subdev registration

[Svyatoslav Ryhel <clamor95@gmail.com>]

The existing driver does not call media subdev registration, making it
invisible to the media framework. Since the LM3560 supports two
independent LEDs, register each LED as a separate media entity.

Because registering LEDs before device initialization may cause access
attempts before the hardware is ready, lm3560_init_device has been moved
before the subdevice initializations.

An additional helper, lm3560_subdev_cleanup, was added to release LED0 if
the initialization of LED1 fails, and to deregister both LEDs in the
remove function.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 drivers/media/i2c/lm3560.c | 34 ++++++++++++++++++++++++----------
 1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/media/i2c/lm3560.c b/drivers/media/i2c/lm3560.c
index f4cc844f4e3c..edfb07587cab 100644
--- a/drivers/media/i2c/lm3560.c
+++ b/drivers/media/i2c/lm3560.c
@@ -364,8 +364,15 @@ static int lm3560_subdev_init(struct lm3560_flash *flash,
 		goto err_out;
 	flash->subdev_led[led_no].entity.function = MEDIA_ENT_F_FLASH;
 
-	return rval;
+	rval = v4l2_async_register_subdev(&flash->subdev_led[led_no]);
+	if (rval < 0) {
+		dev_err(flash->dev, "failed to register V4L2 subdev");
+		goto error_out_media;
+	}
 
+	return rval;
+error_out_media:
+	media_entity_cleanup(&flash->subdev_led[led_no].entity);
 err_out:
 	v4l2_ctrl_handler_free(&flash->ctrls_led[led_no]);
 	return rval;
@@ -391,6 +398,14 @@ static int lm3560_init_device(struct lm3560_flash *flash)
 	return rval;
 }
 
+static void lm3560_subdev_cleanup(struct lm3560_flash *flash,
+				  enum lm3560_led_id led_no)
+{
+	v4l2_async_unregister_subdev(&flash->subdev_led[led_no]);
+	v4l2_ctrl_handler_free(&flash->ctrls_led[led_no]);
+	media_entity_cleanup(&flash->subdev_led[led_no].entity);
+}
+
 static int lm3560_probe(struct i2c_client *client)
 {
 	struct lm3560_flash *flash;
@@ -425,17 +440,19 @@ static int lm3560_probe(struct i2c_client *client)
 	flash->dev = &client->dev;
 	mutex_init(&flash->lock);
 
-	rval = lm3560_subdev_init(flash, LM3560_LED0, "lm3560-led0");
+	rval = lm3560_init_device(flash);
 	if (rval < 0)
 		return rval;
 
-	rval = lm3560_subdev_init(flash, LM3560_LED1, "lm3560-led1");
+	rval = lm3560_subdev_init(flash, LM3560_LED0, "lm3560-led0");
 	if (rval < 0)
 		return rval;
 
-	rval = lm3560_init_device(flash);
-	if (rval < 0)
+	rval = lm3560_subdev_init(flash, LM3560_LED1, "lm3560-led1");
+	if (rval < 0) {
+		lm3560_subdev_cleanup(flash, LM3560_LED0);
 		return rval;
+	}
 
 	i2c_set_clientdata(client, flash);
 
@@ -447,11 +464,8 @@ static void lm3560_remove(struct i2c_client *client)
 	struct lm3560_flash *flash = i2c_get_clientdata(client);
 	unsigned int i;
 
-	for (i = LM3560_LED0; i < LM3560_LED_MAX; i++) {
-		v4l2_device_unregister_subdev(&flash->subdev_led[i]);
-		v4l2_ctrl_handler_free(&flash->ctrls_led[i]);
-		media_entity_cleanup(&flash->subdev_led[i].entity);
-	}
+	for (i = LM3560_LED0; i < LM3560_LED_MAX; i++)
+		lm3560_subdev_cleanup(flash, i);
 }
 
 static const struct i2c_device_id lm3560_id_table[] = {
-- 
2.51.0