Re: [PATCH v2] fbdev: sstfb: Make CONFIG_FB_DEVICE optional

[Thomas Zimmermann <tzimmermann@suse.de>]

Hi

Am 04.10.24 um 17:24 schrieb Gonzalo Silvalde Blanco:
> The sstfb driver currently depends on CONFIG_FB_DEVICE to create sysfs
> entries and access info->dev. This patch wraps the relevant code blocks
> with #ifdef CONFIG_FB_DEVICE, allowing the driver to be built and used
> even if CONFIG_FB_DEVICE is not selected.
>
> The sysfs setting only controls the VGA pass-through state and is not
> required for the display to work correctly.
> (See: http://vogonswiki.com/index.php/VGA_passthrough_cable
> for more information.)
>
> Tested by building with and without CONFIG_FB_DEVICE, both of which
> compiled without issues.
>
> Signed-off-by: Gonzalo Silvalde Blanco <gonzalo.silvalde@gmail.com>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

One thing I forgot, is that you also have to remove the dependency from 
the Kconfig option. [1] Otherwise, it won't be possible to select the 
driver.

Best regards
Thomas

[1] 
https://elixir.bootlin.com/linux/v6.11.2/source/drivers/video/fbdev/Kconfig#L1239

> ---
>   drivers/video/fbdev/sstfb.c | 10 ++++++----
>   1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/video/fbdev/sstfb.c b/drivers/video/fbdev/sstfb.c
> index f8ae54ca0cc3..8d2e9d1f8d80 100644
> --- a/drivers/video/fbdev/sstfb.c
> +++ b/drivers/video/fbdev/sstfb.c
> @@ -716,6 +716,7 @@ static void sstfb_setvgapass( struct fb_info *info, int enable )
>   	pci_write_config_dword(sst_dev, PCI_INIT_ENABLE, tmp);
>   }
>   
> +#ifdef CONFIG_FB_DEVICE
>   static ssize_t store_vgapass(struct device *device, struct device_attribute *attr,
>   			const char *buf, size_t count)
>   {
> @@ -736,10 +737,10 @@ static ssize_t show_vgapass(struct device *device, struct device_attribute *attr
>   	struct sstfb_par *par = info->par;
>   	return sprintf(buf, "%d\n", par->vgapass);
>   }
> -
>   static struct device_attribute device_attrs[] = {
>   	__ATTR(vgapass, S_IRUGO|S_IWUSR, show_vgapass, store_vgapass)
>   	};
> +#endif
>   
>   static int sstfb_ioctl(struct fb_info *info, unsigned int cmd,
>   			unsigned long arg)
> @@ -1435,10 +1436,10 @@ static int sstfb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>   	}
>   
>   	sstfb_clear_screen(info);
> -
> +#fdef CONFIG_FB_DEVICE
>   	if (device_create_file(info->dev, &device_attrs[0]))
>   		printk(KERN_WARNING "sstfb: can't create sysfs entry.\n");
> -
> +#endif
>   
>   	fb_info(info, "%s frame buffer device at 0x%p\n",
>   		fix->id, info->screen_base);
> @@ -1467,8 +1468,9 @@ static void sstfb_remove(struct pci_dev *pdev)
>   
>   	info = pci_get_drvdata(pdev);
>   	par = info->par;
> -
> +#ifdef CONFIG_FB_DEVICE
>   	device_remove_file(info->dev, &device_attrs[0]);
> +#endif
>   	sst_shutdown(info);
>   	iounmap(info->screen_base);
>   	iounmap(par->mmio_vbase);

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)