From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jaya Kumar <jayakumar.lkml@gmail.com>
Date: Tue, 15 Jun 2010 00:16:25 +0000
Subject: Re: [PATCH v3 10/11] [ARM] tegra: Add framebuffer driver
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To: linux-arm-kernel@lists.infradead.org

On Tue, Jun 15, 2010 at 7:59 AM, Jaya Kumar <jayakumar.lkml@gmail.com> wrot=
e:
> On Tue, Jun 15, 2010 at 5:10 AM, Erik Gilling <konkers@android.com> wrote:
>
>> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (tegra_fb_wait_for_event(tegra_fb, HZ/1=
0, DC_INT_FRAME_END))
>
> I still didn't follow how tegra_fb_activate is using the -ETIMEDOUT
> return value from the wait, it seems like it is just ignored. You are
> also doing stuff like HZ/10 and you might prefer to use
> msecs_to_jiffies.
>

I was unclear above. I mean the following code:

+	while (tegra_fb_readl(tegra_fb, DC_CMD_STATE_CONTROL) & 3) {
+		vsync_count++;
+		if (tegra_fb_wait_for_event(tegra_fb, HZ/10, DC_INT_FRAME_END))
+			break;
+	}
+	if (unlikely(vsync_count > 1))
+		pr_warning("%s: waited for %d vsyncs\n", __func__, vsync_count);

It seems to me like the timeout from wait_for_event isn't propagated
back upwards. Maybe it isn't needed but the way the code handles this
seems confusing to me.

Thanks,
jaya