Thread (14 messages) 14 messages, 4 authors, 2024-12-11

Re: [PATCH 1/3] fbdev: Fix recursive dependencies wrt BACKLIGHT_CLASS_DEVICE

From: Helge Deller <deller@gmx.de>
Date: 2024-12-10 23:37:27
Also in: dri-devel, linux-fbdev, linux-staging

On 12/10/24 16:41, Thomas Zimmermann wrote:
Hi


Am 10.12.24 um 15:34 schrieb Helge Deller:
quoted
On 12/10/24 15:29, Helge Deller wrote:
quoted
On 12/10/24 15:09, Thomas Zimmermann wrote:
quoted
diff --git a/drivers/staging/fbtft/Kconfig b/drivers/staging/fbtft/Kconfig
index 77ab44362f16..577e91ff7bf6 100644
--- a/drivers/staging/fbtft/Kconfig
+++ b/drivers/staging/fbtft/Kconfig
@@ -3,6 +3,7 @@ menuconfig FB_TFT
      tristate "Support for small TFT LCD display modules"
      depends on FB && SPI
      depends on FB_DEVICE
+    depends on BACKLIGHT_DEVICE_CLASS
Typo. Should be BACKLIGHT_CLASS_DEVICE...
Ah, thanks. I'll better check the rest of the series for similar mistakes.
quoted
Beside the typo:
In this case, doesn't it make sense to "select BACKLIGHT_DEVICE_CLASS" instead?
That causes the dependency error mentioned in the commit message. This time it's just for fbtft instead of shmobilefb.
quoted
If people want the fbtft, backlight support should be enabled too.
As a user-visible option, it should not be auto-selected
unnecessarily.
Right, it should not be auto-selected.
Unless if fbtft really needs it enabled to function.
IMHO all fb/drm drivers have higher priority than some low-level
background backlight controller code.
The DRM panel drivers already depend on the backlight
instead of selecting it. It's the correct approach.
Sounds wrong IMHO.
As I mentioned
in the cover letter, the few remaining driver that select it should
probably be updated.
That dependency sounds weird, but maybe I simply misunderstand your logic...?

As a Linux end user I usually know which graphic cards are in my machine
and which ones I want to enable.
But as a normal user I think I shouldn't be expected to know
that I first need to enable the "backlight class device"
so that I'm then able to afterwards enable the fbtft (or any other drm/fb driver).

Am I wrong?

Helge
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help