Re: [PATCH] staging: fbtft: convert sysfs attributes to use ATTRIBUTE_GROUPS

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, May 12, 2026 at 11:33:20AM +0000, Harshit Shaw wrote:
> Replace direct device_create_file() calls with the correct
> ATTRIBUTE_GROUPS() macro. Add fbtft_groups as dev_groups in the
> driver structure so the driver core automatically adds and removes
> the sysfs attributes when a device is bound or unbound.
> 
> Signed-off-by: Harshit Shaw <shawharshit116@gmail.com>
> ---
>  drivers/staging/fbtft/fbtft-core.c  |  3 -
>  drivers/staging/fbtft/fbtft-sysfs.c | 86 +++++++++++------------------
>  drivers/staging/fbtft/fbtft.h       |  2 +
>  drivers/staging/fbtft/internal.h    |  3 +-
>  4 files changed, 35 insertions(+), 59 deletions(-)
> 
> diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
> index 3da42c8ca6e3..e6d33127cecc 100644
> --- a/drivers/staging/fbtft/fbtft-core.c
> +++ b/drivers/staging/fbtft/fbtft-core.c
> @@ -782,8 +782,6 @@ int fbtft_register_framebuffer(struct fb_info *fb_info)
>  	if (ret < 0)
>  		goto reg_fail;
>  
> -	fbtft_sysfs_init(par);
> -
>  	if (par->txbuf.buf && par->txbuf.len >= 1024)
>  		sprintf(text1, ", %zu KiB buffer memory", par->txbuf.len >> 10);
>  	if (spi)
> @@ -826,7 +824,6 @@ int fbtft_unregister_framebuffer(struct fb_info *fb_info)
>  
>  	if (par->fbtftops.unregister_backlight)
>  		par->fbtftops.unregister_backlight(par);
> -	fbtft_sysfs_exit(par);
>  	unregister_framebuffer(fb_info);
>  
>  	return 0;
> diff --git a/drivers/staging/fbtft/fbtft-sysfs.c b/drivers/staging/fbtft/fbtft-sysfs.c
> index d05599d80011..416172533e33 100644
> --- a/drivers/staging/fbtft/fbtft-sysfs.c
> +++ b/drivers/staging/fbtft/fbtft-sysfs.c
> @@ -142,37 +142,6 @@ static ssize_t show_gamma_curve(struct device *device,
>  	return sprintf_gamma(par, par->gamma.curves, buf);
>  }
>  
> -static struct device_attribute gamma_device_attrs[] = {
> -	__ATTR(gamma, 0660, show_gamma_curve, store_gamma_curve),
> -};
> -
> -void fbtft_expand_debug_value(unsigned long *debug)
> -{
> -	switch (*debug & 0x7) {
> -	case 1:
> -		*debug |= DEBUG_LEVEL_1;
> -		break;
> -	case 2:
> -		*debug |= DEBUG_LEVEL_2;
> -		break;
> -	case 3:
> -		*debug |= DEBUG_LEVEL_3;
> -		break;
> -	case 4:
> -		*debug |= DEBUG_LEVEL_4;
> -		break;
> -	case 5:
> -		*debug |= DEBUG_LEVEL_5;
> -		break;
> -	case 6:
> -		*debug |= DEBUG_LEVEL_6;
> -		break;
> -	case 7:
> -		*debug = 0xFFFFFFFF;
> -		break;
> -	}
> -}
> -
>  static ssize_t store_debug(struct device *device,
>  			   struct device_attribute *attr,
>  			   const char *buf, size_t count)
> @@ -198,31 +167,40 @@ static ssize_t show_debug(struct device *device,
>  	return sysfs_emit(buf, "%lu\n", par->debug);
>  }
>  
> -static struct device_attribute debug_device_attr =
> -	__ATTR(debug, 0660, show_debug, store_debug);
> -
> -void fbtft_sysfs_init(struct fbtft_par *par)
> +void fbtft_expand_debug_value(unsigned long *debug)
>  {
> -	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(dev, &gamma_device_attrs[0]);
> +	switch (*debug & 0x7) {
> +	case 1:
> +		*debug |= DEBUG_LEVEL_1;
> +		break;
> +	case 2:
> +		*debug |= DEBUG_LEVEL_2;
> +		break;
> +	case 3:
> +		*debug |= DEBUG_LEVEL_3;
> +		break;
> +	case 4:
> +		*debug |= DEBUG_LEVEL_4;
> +		break;
> +	case 5:
> +		*debug |= DEBUG_LEVEL_5;
> +		break;
> +	case 6:
> +		*debug |= DEBUG_LEVEL_6;
> +		break;
> +	case 7:
> +		*debug = 0xFFFFFFFF;
> +		break;
> +	}
>  }
>  
> -void fbtft_sysfs_exit(struct fbtft_par *par)
> -{
> -	struct device *dev;
> +static DEVICE_ATTR_RW(debug);
> +static DEVICE_ATTR_RW(gamma);
>  
> -	dev = dev_of_fbinfo(par->info);
> -	if (!dev)
> -		return;
> +static struct attribute *fbtft_attrs[] = {
> +	&dev_attr_debug.attr,
> +	&dev_attr_gamma.attr,
> +	NULL,
> +};
>  
> -	device_remove_file(dev, &debug_device_attr);
> -	if (par->gamma.curves && par->fbtftops.set_gamma)
> -		device_remove_file(dev, &gamma_device_attrs[0]);
> -}
> +ATTRIBUTE_GROUPS(fbtft);
> diff --git a/drivers/staging/fbtft/fbtft.h b/drivers/staging/fbtft/fbtft.h
> index 317be17b95c1..ab71db017d05 100644
> --- a/drivers/staging/fbtft/fbtft.h
> +++ b/drivers/staging/fbtft/fbtft.h
> @@ -299,6 +299,7 @@ static struct spi_driver fbtft_driver_spi_driver = {				\
>  	.driver = {								\
>  		.name = _name,							\
>  		.of_match_table = dt_ids,					\
> +		.dev_groups = fbtft_groups,					\
>  	},									\
>  	.id_table = _spi_ids,							\
>  	.probe = fbtft_driver_probe_spi,					\
> @@ -328,6 +329,7 @@ static struct platform_driver fbtft_driver_platform_driver = {             \
>  		.name   = _name,                                           \
>  		.owner  = THIS_MODULE,                                     \
>  		.of_match_table = dt_ids,                                  \
> +		.dev_groups = fbtft_groups,                                \
>  	},                                                                 \
>  	.probe  = fbtft_driver_probe_pdev,                                 \
>  	.remove = fbtft_driver_remove_pdev,				   \
> diff --git a/drivers/staging/fbtft/internal.h b/drivers/staging/fbtft/internal.h
> index ae2ff4a4a472..39fd1e167b41 100644
> --- a/drivers/staging/fbtft/internal.h
> +++ b/drivers/staging/fbtft/internal.h
> @@ -4,8 +4,7 @@
>  #ifndef __LINUX_FBTFT_INTERNAL_H
>  #define __LINUX_FBTFT_INTERNAL_H
>  
> -void fbtft_sysfs_init(struct fbtft_par *par);
> -void fbtft_sysfs_exit(struct fbtft_par *par);
> +extern const struct attribute_group *fbtft_groups[];
>  void fbtft_expand_debug_value(unsigned long *debug);
>  int fbtft_gamma_parse_str(struct fbtft_par *par, u32 *curves,
>  			  const char *str, int size);
> -- 
> 2.53.0
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
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created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
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