[PATCH 4.14 170/251] auxdisplay: ht16k33: Connect backlight to fbdev

From: Greg Kroah-Hartman
Date: Wed Nov 24 2021 - 07:43:29 EST


From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>

[ Upstream commit 80f9eb70fd9276938f0a131f76d438021bfd8b34 ]

Currently /sys/class/graphics/fb0/bl_curve is not accessible (-ENODEV),
as the driver does not connect the backlight to the frame buffer device.
Fix this moving backlight initialization up, and filling in
fb_info.bl_dev.

Fixes: 8992da44c6805d53 ("auxdisplay: ht16k33: Driver for LED controller")
Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Reviewed-by: Robin van der Gracht <robin@xxxxxxxxxxx>
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/auxdisplay/ht16k33.c | 56 ++++++++++++++++++------------------
1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/drivers/auxdisplay/ht16k33.c b/drivers/auxdisplay/ht16k33.c
index eec69213dad4f..e3c8f355f9a62 100644
--- a/drivers/auxdisplay/ht16k33.c
+++ b/drivers/auxdisplay/ht16k33.c
@@ -426,6 +426,33 @@ static int ht16k33_probe(struct i2c_client *client,
if (err)
return err;

+ /* Backlight */
+ memset(&bl_props, 0, sizeof(struct backlight_properties));
+ bl_props.type = BACKLIGHT_RAW;
+ bl_props.max_brightness = MAX_BRIGHTNESS;
+
+ bl = devm_backlight_device_register(&client->dev, DRIVER_NAME"-bl",
+ &client->dev, priv,
+ &ht16k33_bl_ops, &bl_props);
+ if (IS_ERR(bl)) {
+ dev_err(&client->dev, "failed to register backlight\n");
+ return PTR_ERR(bl);
+ }
+
+ err = of_property_read_u32(node, "default-brightness-level",
+ &dft_brightness);
+ if (err) {
+ dft_brightness = MAX_BRIGHTNESS;
+ } else if (dft_brightness > MAX_BRIGHTNESS) {
+ dev_warn(&client->dev,
+ "invalid default brightness level: %u, using %u\n",
+ dft_brightness, MAX_BRIGHTNESS);
+ dft_brightness = MAX_BRIGHTNESS;
+ }
+
+ bl->props.brightness = dft_brightness;
+ ht16k33_bl_update_status(bl);
+
/* Framebuffer (2 bytes per column) */
BUILD_BUG_ON(PAGE_SIZE < HT16K33_FB_SIZE);
fbdev->buffer = (unsigned char *) get_zeroed_page(GFP_KERNEL);
@@ -458,6 +485,7 @@ static int ht16k33_probe(struct i2c_client *client,
fbdev->info->screen_size = HT16K33_FB_SIZE;
fbdev->info->fix = ht16k33_fb_fix;
fbdev->info->var = ht16k33_fb_var;
+ fbdev->info->bl_dev = bl;
fbdev->info->pseudo_palette = NULL;
fbdev->info->flags = FBINFO_FLAG_DEFAULT;
fbdev->info->par = priv;
@@ -470,34 +498,6 @@ static int ht16k33_probe(struct i2c_client *client,
if (err)
goto err_fbdev_unregister;

- /* Backlight */
- memset(&bl_props, 0, sizeof(struct backlight_properties));
- bl_props.type = BACKLIGHT_RAW;
- bl_props.max_brightness = MAX_BRIGHTNESS;
-
- bl = devm_backlight_device_register(&client->dev, DRIVER_NAME"-bl",
- &client->dev, priv,
- &ht16k33_bl_ops, &bl_props);
- if (IS_ERR(bl)) {
- dev_err(&client->dev, "failed to register backlight\n");
- err = PTR_ERR(bl);
- goto err_fbdev_unregister;
- }
-
- err = of_property_read_u32(node, "default-brightness-level",
- &dft_brightness);
- if (err) {
- dft_brightness = MAX_BRIGHTNESS;
- } else if (dft_brightness > MAX_BRIGHTNESS) {
- dev_warn(&client->dev,
- "invalid default brightness level: %u, using %u\n",
- dft_brightness, MAX_BRIGHTNESS);
- dft_brightness = MAX_BRIGHTNESS;
- }
-
- bl->props.brightness = dft_brightness;
- ht16k33_bl_update_status(bl);
-
ht16k33_fb_queue(priv);
return 0;

--
2.33.0