fbdev/vga16fb: Create EGA/VGA devices in sysfb code

Move the device-creation from vga16fb to sysfb code. The driver's
videomode checks are independent from device creation, so move them
into vga16fb's probe function. This will allow to create the module
init/exit code automatically.

The vga16fb driver requires a screen_info for type VIDEO_TYPE_VGAC
or VIDEO_TYPE_EGAC. Such code is nowhere present in the kernel, except
for some MIPS systems. It's not clear if the vga16fb driver actually
works in practice.

v2:
	* keep driver name to "vga16fb" (Javier)
	* give rational for moving mode checks (Javier)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220718072322.8927-3-tzimmermann@suse.de

diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
index 1f276f1..3fd3563 100644 (file)
--- a/drivers/firmware/sysfb.c
+++ b/drivers/firmware/sysfb.c
@@ -94,6 +94,10 @@ static __init int sysfb_init(void)
                name = "efi-framebuffer";
        else if (si->orig_video_isVGA == VIDEO_TYPE_VLFB)
                name = "vesa-framebuffer";
+       else if (si->orig_video_isVGA == VIDEO_TYPE_VGAC)
+               name = "vga-framebuffer";
+       else if (si->orig_video_isVGA == VIDEO_TYPE_EGAC)
+               name = "ega-framebuffer";
        else
                name = "platform-framebuffer";
 

diff --git a/drivers/video/fbdev/vga16fb.c b/drivers/video/fbdev/vga16fb.c
index faf7697..9e614c1 100644 (file)
--- a/drivers/video/fbdev/vga16fb.c
+++ b/drivers/video/fbdev/vga16fb.c
@@ -185,19 +185,19 @@ static inline void setindex(int index)
 }
 
 /* Check if the video mode is supported by the driver */
-static inline int check_mode_supported(void)
+static inline int check_mode_supported(const struct screen_info *si)
 {
        /* non-x86 architectures treat orig_video_isVGA as a boolean flag */
 #if defined(CONFIG_X86)
        /* only EGA and VGA in 16 color graphic mode are supported */
-       if (screen_info.orig_video_isVGA != VIDEO_TYPE_EGAC &&
-           screen_info.orig_video_isVGA != VIDEO_TYPE_VGAC)
+       if (si->orig_video_isVGA != VIDEO_TYPE_EGAC &&
+           si->orig_video_isVGA != VIDEO_TYPE_VGAC)
                return -ENODEV;
 
-       if (screen_info.orig_video_mode != 0x0D &&      /* 320x200/4 (EGA) */
-           screen_info.orig_video_mode != 0x0E &&      /* 640x200/4 (EGA) */
-           screen_info.orig_video_mode != 0x10 &&      /* 640x350/4 (EGA) */
-           screen_info.orig_video_mode != 0x12)        /* 640x480/4 (VGA) */
+       if (si->orig_video_mode != 0x0D &&      /* 320x200/4 (EGA) */
+           si->orig_video_mode != 0x0E &&      /* 640x200/4 (EGA) */
+           si->orig_video_mode != 0x10 &&      /* 640x350/4 (EGA) */
+           si->orig_video_mode != 0x12)        /* 640x480/4 (VGA) */
                return -ENODEV;
 #endif
        return 0;
@@ -1321,11 +1321,20 @@ static int __init vga16fb_setup(char *options)
 
 static int vga16fb_probe(struct platform_device *dev)
 {
+       struct screen_info *si;
        struct fb_info *info;
        struct vga16fb_par *par;
        int i;
        int ret = 0;
 
+       si = dev_get_platdata(&dev->dev);
+       if (!si)
+               return -ENODEV;
+
+       ret = check_mode_supported(si);
+       if (ret)
+               return ret;
+
        printk(KERN_DEBUG "vga16fb: initializing\n");
        info = framebuffer_alloc(sizeof(struct vga16fb_par), &dev->dev);
 
@@ -1352,10 +1361,10 @@ static int vga16fb_probe(struct platform_device *dev)
        par = info->par;
 
 #if defined(CONFIG_X86)
-       par->isVGA = screen_info.orig_video_isVGA == VIDEO_TYPE_VGAC;
+       par->isVGA = si->orig_video_isVGA == VIDEO_TYPE_VGAC;
 #else
        /* non-x86 architectures treat orig_video_isVGA as a boolean flag */
-       par->isVGA = screen_info.orig_video_isVGA;
+       par->isVGA = si->orig_video_isVGA;
 #endif
        par->palette_blanked = 0;
        par->vesa_blanked = 0;
@@ -1425,16 +1434,21 @@ static int vga16fb_remove(struct platform_device *dev)
        return 0;
 }
 
+static const struct platform_device_id vga16fb_driver_id_table[] = {
+       {"ega-framebuffer", 0},
+       {"vga-framebuffer", 0},
+       { }
+};
+
 static struct platform_driver vga16fb_driver = {
        .probe = vga16fb_probe,
        .remove = vga16fb_remove,
        .driver = {
                .name = "vga16fb",
        },
+       .id_table = vga16fb_driver_id_table,
 };
 
-static struct platform_device *vga16fb_device;
-
 static int __init vga16fb_init(void)
 {
        int ret;
@@ -1447,32 +1461,15 @@ static int __init vga16fb_init(void)
        vga16fb_setup(option);
 #endif
 
-       ret = check_mode_supported();
+       ret = platform_driver_register(&vga16fb_driver);
        if (ret)
                return ret;
 
-       ret = platform_driver_register(&vga16fb_driver);
-
-       if (!ret) {
-               vga16fb_device = platform_device_alloc("vga16fb", 0);
-
-               if (vga16fb_device)
-                       ret = platform_device_add(vga16fb_device);
-               else
-                       ret = -ENOMEM;
-
-               if (ret) {
-                       platform_device_put(vga16fb_device);
-                       platform_driver_unregister(&vga16fb_driver);
-               }
-       }
-
-       return ret;
+       return 0;
 }
 
 static void __exit vga16fb_exit(void)
 {
-       platform_device_unregister(vga16fb_device);
        platform_driver_unregister(&vga16fb_driver);
 }