[PATCH v4 2/4] staging: fbtft: Make FB_DEVICE dependency optional

Chintan Patel
2026-01-07T04:43:17Z

fbtft provides sysfs interfaces for debugging and gamma configuration,
but these are not required for the core driver.

Drop the hard dependency on CONFIG_FB_DEVICE and make sysfs support
optional by using dev_of_fbinfo() at runtime. When FB_DEVICE is disabled,
sysfs operations are skipped while the code remains buildable and
type-checked.

Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Suggested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Chintan Patel <chintanlike@gmail.com>
---
drivers/staging/fbtft/Kconfig | 5 ++++-
drivers/staging/fbtft/fbtft-sysfs.c | 20 ++++++++++++++++----
2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/fbtft/Kconfig b/drivers/staging/fbtft/Kconfig
index c2655768209a..578412a2f379 100644
--- a/drivers/staging/fbtft/Kconfig
+++ b/drivers/staging/fbtft/Kconfig
@@ -2,11 +2,14 @@
menuconfig FB_TFT
tristate "Support for small TFT LCD display modules"
depends on FB && SPI
- depends on FB_DEVICE
depends on BACKLIGHT_CLASS_DEVICE
depends on GPIOLIB || COMPILE_TEST
select FB_BACKLIGHT
select FB_SYSMEM_HELPERS_DEFERRED
+ help
+ Support for small TFT LCD display modules over SPI bus. FB_DEVICE
+ is not required, but if enabled, provides sysfs interface for debugging
+ and gamma curve configuration.

if FB_TFT

diff --git a/drivers/staging/fbtft/fbtft-sysfs.c b/drivers/staging/fbtft/fbtft-sysfs.c
index e45c90a03a90..d05599d80011 100644
--- a/drivers/staging/fbtft/fbtft-sysfs.c
+++ b/drivers/staging/fbtft/fbtft-sysfs.c
@@ -203,14 +203,26 @@ static struct device_attribute debug_device_attr =

void fbtft_sysfs_init(struct fbtft_par *par)
{
- device_create_file(par->info->dev, &debug_device_attr);
+ struct device *dev;
+
+ dev = dev_of_fbinfo(par->info);
+ if (!dev)
+ return;
+
+ device_create_file(dev, &debug_device_attr);
if (par->gamma.curves && par->fbtftops.set_gamma)
- device_create_file(par->info->dev, &gamma_device_attrs[0]);
+ device_create_file(dev, &gamma_device_attrs[0]);
}

void fbtft_sysfs_exit(struct fbtft_par *par)
{
- device_remove_file(par->info->dev, &debug_device_attr);
+ struct device *dev;
+
+ dev = dev_of_fbinfo(par->info);
+ if (!dev)
+ return;
+
+ device_remove_file(dev, &debug_device_attr);
if (par->gamma.curves && par->fbtftops.set_gamma)
- device_remove_file(par->info->dev, &gamma_device_attrs[0]);
+ device_remove_file(dev, &gamma_device_attrs[0]);
}
--
2.43.0