fbdev: ssd1307fb: Init backlight before registering framebuffer

For drivers that support backlight, LCD and fbdev devices, fbdev has
to be initialized last. See documentation for struct fbinfo.bl_dev.

The backlight name's index number comes from register_framebuffer(),
which now happens after initializing the backlight device. So like
in all other backlight drivers, we now give the backlight device a
generic name without the fbdev index.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20240305162425.23845-9-tzimmermann@suse.de
Signed-off-by: Lee Jones <lee@kernel.org>

Author: tdz

drivers/video/fbdev/ssd1307fb.c

@@ -594,7 +594,6 @@ static int ssd1307fb_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
 	struct backlight_device *bl;
-	char bl_name[12];
 	struct fb_info *info;
 	struct fb_deferred_io *ssd1307fb_defio;
 	u32 vmem_size;
@@ -733,31 +732,30 @@ static int ssd1307fb_probe(struct i2c_client *client)
 	if (ret)
 		goto regulator_enable_error;
 
-	ret = register_framebuffer(info);
-	if (ret) {
-		dev_err(dev, "Couldn't register the framebuffer\n");
-		goto panel_init_error;
-	}
-
-	snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node);
-	bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops,
+	bl = backlight_device_register("ssd1307fb-bl", dev, par, &ssd1307fb_bl_ops,
 				       NULL);
 	if (IS_ERR(bl)) {
 		ret = PTR_ERR(bl);
 		dev_err(dev, "unable to register backlight device: %d\n", ret);
-		goto bl_init_error;
+		goto panel_init_error;
+	}
+	info->bl_dev = bl;
+
+	ret = register_framebuffer(info);
+	if (ret) {
+		dev_err(dev, "Couldn't register the framebuffer\n");
+		goto fb_init_error;
 	}
 
 	bl->props.brightness = par->contrast;
 	bl->props.max_brightness = MAX_CONTRAST;
-	info->bl_dev = bl;
 
 	dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
 
 	return 0;
 
-bl_init_error:
-	unregister_framebuffer(info);
+fb_init_error:
+	backlight_device_unregister(bl);
 panel_init_error:
 	pwm_disable(par->pwm);
 	pwm_put(par->pwm);