diff options
Diffstat (limited to 'drivers/video/fbdev/core/fb_info.c')
-rw-r--r-- | drivers/video/fbdev/core/fb_info.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/fb_info.c b/drivers/video/fbdev/core/fb_info.c new file mode 100644 index 000000000000..4847ebe50d7d --- /dev/null +++ b/drivers/video/fbdev/core/fb_info.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/export.h> +#include <linux/fb.h> +#include <linux/mutex.h> +#include <linux/slab.h> + +/** + * framebuffer_alloc - creates a new frame buffer info structure + * + * @size: size of driver private data, can be zero + * @dev: pointer to the device for this fb, this can be NULL + * + * Creates a new frame buffer info structure. Also reserves @size bytes + * for driver private data (info->par). info->par (if any) will be + * aligned to sizeof(long). The new instances of struct fb_info and + * the driver private data are both cleared to zero. + * + * Returns the new structure, or NULL if an error occurred. + * + */ +struct fb_info *framebuffer_alloc(size_t size, struct device *dev) +{ +#define BYTES_PER_LONG (BITS_PER_LONG/8) +#define PADDING (BYTES_PER_LONG - (sizeof(struct fb_info) % BYTES_PER_LONG)) + int fb_info_size = sizeof(struct fb_info); + struct fb_info *info; + char *p; + + if (size) + fb_info_size += PADDING; + + p = kzalloc(fb_info_size + size, GFP_KERNEL); + + if (!p) + return NULL; + + info = (struct fb_info *) p; + + if (size) + info->par = p + fb_info_size; + + info->device = dev; + info->fbcon_rotate_hint = -1; + +#if IS_ENABLED(CONFIG_FB_BACKLIGHT) + mutex_init(&info->bl_curve_mutex); +#endif + + return info; +#undef PADDING +#undef BYTES_PER_LONG +} +EXPORT_SYMBOL(framebuffer_alloc); + +/** + * framebuffer_release - marks the structure available for freeing + * + * @info: frame buffer info structure + * + * Drop the reference count of the device embedded in the + * framebuffer info structure. + * + */ +void framebuffer_release(struct fb_info *info) +{ + if (!info) + return; + + if (WARN_ON(refcount_read(&info->count))) + return; + +#if IS_ENABLED(CONFIG_FB_BACKLIGHT) + mutex_destroy(&info->bl_curve_mutex); +#endif + + kfree(info); +} +EXPORT_SYMBOL(framebuffer_release); |