fbdev: goldfishfb: fail pan display on base-update timeout

goldfish_fb_pan_display() waits for the device to acknowledge the new
framebuffer base, but it only logs a timeout and still reports success.
The probe path also ignores the initial pan-display result before
registering the framebuffer.

Return -ETIMEDOUT when the base-update acknowledgment does not arrive,
and propagate that error from the initial probe-time base update before
the framebuffer is published.

Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/drivers/video/fbdev/goldfishfb.c b/drivers/video/fbdev/goldfishfb.c
index c9871281bc1dabe91ee794fa92352c7ead151afe..e5d79886ea66b1fe8108c9dbbcc52707a7a55bf4 100644 (file)
--- a/drivers/video/fbdev/goldfishfb.c
+++ b/drivers/video/fbdev/goldfishfb.c
@@ -138,10 +138,12 @@ static int goldfish_fb_pan_display(struct fb_var_screeninfo *var,
        writel(fb->fb.fix.smem_start + fb->fb.var.xres * 2 * var->yoffset,
                                                fb->reg_base + FB_SET_BASE);
        spin_unlock_irqrestore(&fb->lock, irq_flags);
-       wait_event_timeout(fb->wait,
-                       fb->base_update_count != base_update_count, HZ / 15);
-       if (fb->base_update_count == base_update_count)
+       if (!wait_event_timeout(fb->wait,
+                               fb->base_update_count != base_update_count,
+                               HZ / 15)) {
                pr_err("%s: timeout waiting for base update\n", __func__);
+               return -ETIMEDOUT;
+       }
        return 0;
 }
 
@@ -251,7 +253,9 @@ static int goldfish_fb_probe(struct platform_device *pdev)
                goto err_request_irq_failed;
 
        writel(FB_INT_BASE_UPDATE_DONE, fb->reg_base + FB_INT_ENABLE);
-       goldfish_fb_pan_display(&fb->fb.var, &fb->fb); /* updates base */
+       ret = goldfish_fb_pan_display(&fb->fb.var, &fb->fb); /* updates base */
+       if (ret)
+               goto err_pan_display_failed;
 
        ret = register_framebuffer(&fb->fb);
        if (ret)
@@ -259,6 +263,7 @@ static int goldfish_fb_probe(struct platform_device *pdev)
        return 0;
 
 err_register_framebuffer_failed:
+err_pan_display_failed:
        free_irq(fb->irq, fb);
 err_request_irq_failed:
 err_fb_set_var_failed: