Add module to get video driver chosen by uboot (MiyooCFW#83)

arch/arm/configs/miyoo_defconfig

@@ -63,6 +63,7 @@ CONFIG_MFD_SYSCON=y
 CONFIG_REGULATOR=y
 CONFIG_REGULATOR_FIXED_VOLTAGE=y
 CONFIG_FB=y
+CONFIG_FB_MIYOO_VIDEO=y
 CONFIG_FB_R61520=m
 CONFIG_FB_GC9306=m
 CONFIG_FB_ST7789S=m

drivers/video/fbdev/Kconfig

@@ -2237,6 +2237,13 @@ config FB_SM712
 	  This driver is also available as a module. The module will be
 	  called sm712fb. If you want to compile it as a module, say M
 	  here and read <file:Documentation/kbuild/modules.rst>.
+
+config FB_MIYOO_VIDEO
+	tristate "Get video driver chosen by uboot"
+	depends on FB
+        help
+	  Returns name of video driver in /sys/kernel/miyoo_video/miyoo_video file
+
 config FB_R61520
 	tristate "Renesas R61520 SLCD framebuffer support"
 	depends on FB

drivers/video/fbdev/Makefile

@@ -120,11 +120,13 @@ obj-$(CONFIG_FB_OPENCORES)	  += ocfb.o
 obj-$(CONFIG_FB_SM712)		  += sm712fb.o
 obj-$(CONFIG_FB_R61520)		  += r61520fb.o
 obj-$(CONFIG_FB_GC9306)		  += gc9306fb.o
-obj-$(CONFIG_FB_ST7789S)		  += st7789sfb.o
-obj-$(CONFIG_FB_ST7789S_TE)		  += st7789sTEfb.o
-obj-$(CONFIG_FB_RM68090)		  += rm68090fb.o
-obj-$(CONFIG_FB_HX8347D)		  += hx8347dfb.o
+obj-$(CONFIG_FB_ST7789S)	  += st7789sfb.o
+obj-$(CONFIG_FB_ST7789S_TE)	  += st7789sTEfb.o
+obj-$(CONFIG_FB_RM68090)	  += rm68090fb.o
+obj-$(CONFIG_FB_HX8347D)	  += hx8347dfb.o
 obj-$(CONFIG_FB_TVOUT)		  += miyoo-tvout.o
+obj-$(CONFIG_FB_MIYOO_VIDEO)	  += miyoo-video.o
+
 
 # Platform or fallback drivers go here
 obj-$(CONFIG_FB_UVESA)            += uvesafb.o

drivers/video/fbdev/miyoo-video.c

@@ -0,0 +1,70 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/sysfs.h>
+
+#define SYSFS_DIR "miyoo_video"
+#define SYSFS_FILE "miyoo_video"
+
+static struct kobject *video_kobj;
+static char *driver = "";
+
+module_param(driver, charp, S_IRUGO);
+MODULE_PARM_DESC(driver, "Name of video driver to load");
+
+static ssize_t miyoo_video_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
+{
+    return sprintf(buf, "%s", driver);
+}
+
+static ssize_t miyoo_video_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count)
+{
+    pr_info("Received %zu bytes: %s\n", count, buf);
+    return count;
+}
+
+static struct kobj_attribute miyoo_video_attribute =
+    __ATTR(miyoo_video, 0664, miyoo_video_show, miyoo_video_store);
+
+static int __init sysfs_miyoo_init(void)
+{
+    int result;
+
+    pr_info("Miyoo video driver name module loaded\n");
+
+    video_kobj = kobject_create_and_add(SYSFS_DIR, kernel_kobj);
+    if (!video_kobj)
+    {
+        pr_err("Failed to create sysfs directory\n");
+        return -ENOMEM;
+    }
+
+    result = sysfs_create_file(video_kobj, &miyoo_video_attribute.attr);
+    if (result)
+    {
+        pr_err("Failed to create sysfs file\n");
+        kobject_put(video_kobj);
+        return result;
+    }
+
+    return 0;
+}
+
+static void __exit sysfs_miyoo_exit(void)
+{
+    pr_info("Miyoo video driver name module unloaded\n");
+
+    if (video_kobj)
+    {
+        kobject_put(video_kobj);
+        sysfs_remove_file(kernel_kobj, &miyoo_video_attribute.attr);
+    }
+}
+
+module_init(sysfs_miyoo_init);
+module_exit(sysfs_miyoo_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("tiopex [email protected]");
+MODULE_DESCRIPTION("Kernel module with a name of video driver from uboot");