We register each available framebuffer in the system with the fblog driver
so we always know all active devices. We directly open the fb-driver,
initialize the buffer and load a font so we are ready for drawing
operations. If a device cannot be opened, we mark it as dead and ignore it
in all other functions.
Signed-off-by: David Herrmann <dh.herrmann@xxxxxxxxxxxxxx>
---
drivers/video/console/fblog.c | 108 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 108 insertions(+)
diff --git a/drivers/video/console/fblog.c b/drivers/video/console/fblog.c
index 1504ba9..8038dcc 100644
--- a/drivers/video/console/fblog.c
+++ b/drivers/video/console/fblog.c
@@ -39,6 +39,14 @@
#include <linux/font.h>
#include <linux/module.h>
+#define FBLOG_STR(x) x, sizeof(x) - 1
+
+enum fblog_flags {
+ FBLOG_KILLED,
+ FBLOG_SUSPENDED,
+ FBLOG_BLANKED,
+};
+
/**
* struct fblog_buf: Console text buffer
*
@@ -61,6 +69,30 @@ struct fblog_buf {
size_t pos_y;
};
+/**
+ * struct fblog_fb: Framebuffer object
+ *
+ * For each framebuffer we register this object. It contains all data we need to
+ * display the console log on it. The index of a framebuffer in registered_fb[]
+ * is the same as in fblog_fbs[]. So the following must always be true if the
+ * pointers are non-NULL:
+ * registered_fb[idx] == fblog_fbs[idx]->info
+ * fblog_fbs[idx]->info->node == idx
+ *
+ * flags: Framebuffer flags (see fblog_flags)
+ * info: Pointer to the associated framebuffer device
+ * font: Currently used font
+ * buf: Console text buffer
+ */
+struct fblog_fb {
+ unsigned long flags;
+ struct fb_info *info;
+ const struct font_desc *font;
+ struct fblog_buf buf;
+};
+
+static struct fblog_fb *fblog_fbs[FB_MAX];
+
static void fblog_buf_resize(struct fblog_buf *buf, size_t width,
size_t height)
{
@@ -165,6 +197,82 @@ static void fblog_buf_write(struct fblog_buf *buf, const char *str, size_t len)
}
}
+static struct fblog_fb *fblog_info2fb(struct fb_info *info)
+{
+ if (!info || info->node < 0 || info->node >= FB_MAX ||
+ !registered_fb[info->node])
+ return NULL;
+
+ return fblog_fbs[info->node];
+}
+
+static void fblog_register(struct fb_info *info)
+{
+ struct fblog_fb *fb;
+ struct fb_var_screeninfo var;
+ const struct fb_videomode *mode;
+ unsigned int width, height;
+
+ if (!info || info->node < 0 || info->node >= FB_MAX)
+ return;
+ if (!registered_fb[info->node] || fblog_fbs[info->node])
+ return;
+
+ fb = kzalloc(sizeof(*fb), GFP_KERNEL);
+ if (!fb)
+ return;
+
+ fblog_fbs[info->node] = fb;
+ fb->info = info;
+ fblog_buf_init(&fb->buf);
+ fblog_buf_write(&fb->buf, FBLOG_STR("Framebuffer log initialized\n"));
+
+ if (!try_module_get(info->fbops->owner))
+ goto out_killed;
+ if (info->fbops->fb_open && info->fbops->fb_open(info, 0))
+ goto out_unref;
+
+ var = info->var;
+ mode = fb_find_best_mode(&var, &info->modelist);
+ var.activate = FB_ACTIVATE_NOW | FB_ACTIVATE_FORCE;
+ fb_set_var(info, &var);
+
+ fb->font = get_default_font(info->var.xres, info->var.yres,
+ info->pixmap.blit_x,
+ info->pixmap.blit_y);
+ if (fb->font) {
+ width = info->var.xres / fb->font->width;
+ height = info->var.yres / fb->font->height;
+ fblog_buf_resize(&fb->buf, width, height);
+ }
+
+ return;
+
+out_unref:
+ module_put(info->fbops->owner);
+out_killed:
+ set_bit(FBLOG_KILLED, &fb->flags);
+}
+
+static void fblog_unregister(struct fblog_fb *fb)
+{
+ struct fb_info *info;
+
+ if (!fb)
+ return;
+
+ info = fb->info;
+ if (!test_bit(FBLOG_KILLED, &fb->flags)) {
+ if (info->fbops->fb_release)
+ info->fbops->fb_release(info, 0);
+ module_put(info->fbops->owner);
+ }
+
+ fblog_buf_deinit(&fb->buf);
+ fblog_fbs[info->node] = NULL;
+ kfree(fb);
+}
+
static int __init fblog_init(void)
{
return 0;
--
1.7.10.4
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